Journal articles on the topic 'Boron deficiency; Ribonucleic acid metabolism'

Boron-phosphorus interaction was observed in maize (Zea mays L. ’Ganga 2’) when grown in refined sand at three levels of boron, deficient (0.0033 mg L−1), normal (0.33 mg L−1) and excess (3.3 mg L−1), each at three levels of phosphorus, deficient (0.17 m mol L−1), normal (1.5 mmol L−1) and excess (4 m mol L−1). The effects of phosphorus deficiency (i.e., reduction in dry matter, soluble protein, DNA, activity of ribonuclease and increase in the activities of peroxidase, acid phosphatase and polyphenol oxidase) were intensified by a combined deficiency of boron and phosphorus. The effects of boron deficiency (i.e., reduction in dry weight, leaf boron and DNA and increase in starch content and in the activities of starch phosphorylase, peroxidase and polyphenol oxidase) become more intense in the treatment-deficient B-excess P. The decreases caused by excess phosphorus (i.e., dry weight, starch and sugar content, DNA, RNA and activity of ribonuclease) were aggravated by combined excess of boron and phosphorus.Key words: Zea mays, maize, boron and phosphorus nutrition

Boron is an essential plant micronutrient taken up via the roots mostly in the form of boric acid. Its important role in plant metabolism involves the stabilization of molecules with cis-diol groups. The element is involved in the cell wall and membrane structure and functioning; therefore, it participates in numerous ion, metabolite, and hormone transport reactions. Boron has an extremely narrow range between deficiency and toxicity, and inadequate boron supply exhibits a detrimental effect on the yield of agricultural plants. The deficiency problem can be solved by fertilization, whereas soil boron toxicity can be ameliorated using various procedures; however, these approaches are costly and time-consuming, and they often show temporary effects. Plant species, as well as the genotypes within the species, dramatically differ in terms of boron requirements; thus, the available soil boron which is deficient for one crop may exhibit toxic effects on another. The widely documented intraspecies genetic variability regarding boron utilization efficiency and toxicity tolerance, together with the knowledge of the physiology and genetics of boron, should result in the development of efficient and tolerant varieties that may represent a long-term sustainable solution for the problem of inadequate or excess boron supply.

Diabetes mellitus is associated with a reduction of lipoprotein lipase (LPL) activity in adipose tissue and development of hypertriglyceridemia. To determine how a condition of severe insulin deficiency affects mammary gland LPL activity and mRNA expression during late pregnancy, streptozotocin (STZ) treated (40 mg/kg) and non-treated (control) virgin and 20 day pregnant rats were studied. In control rats, both LPL activity and mRNA were higher in pregnant than in virgin rats. When compared to control rats, STZ-treated rats, either pregnant or virgin, showed decreased LPL activity and mRNA content. Furthermore, mammary gland LPL activity was linearly correlated with mRNA content, and either variable was linearly correlated with plasma insulin levels. Thus, insulin deficiency impairs the expression of LPL in mammary glands, revealing the role of insulin as a modulator of the enzyme at the mRNA expression level.

Since the essentiality of boron (B) to plant growth was reported nearly one century ago, the implication of B in physiological performance, productivity and quality of agricultural products, and the morphogenesis of apical meristem in plants has widely been studied. B stresses (B deficiency and toxicity), which lead to atrophy of canopy and deterioration of Citrus fruits, have long been discovered in citrus orchards. This paper reviews the research progress of B stresses on Citrus growth, photosynthesis, light use efficiency, nutrient absorption, organic acid metabolism, sugar metabolism and relocation, and antioxidant system. Moreover, the beneficial effects of B on plant stress tolerance and further research in this area were also discussed.

Twenty-one hydroxylase (P450c21) is a key enzyme essential for normal zona glomerulosa and fasciculata function. Recently, 21-hydroxylase deficiency has been implicated in the pathogenesis of adrenocortical tumors. Therefore, we investigated the mutational spectrum of the CYP21B gene and the messenger RNA expression of P450c21 in six aldosterone-producing adenomas, seven cortisol-producing adenomas, two nonfunctional incidentally detected adenomas, and four adrenal carcinomas. DNA from leukocytes and tumors was amplified by PCR using primers specific for the CYP21B gene. The 10 exons, intron 2, intron 7, all other exon/intron junctions, and 380 bp of the promoter region of CYP21B were automatically sequenced. Poly(A) RNA was extracted from tumor tissue, dot blotted on a nylon membrane, and hybridized with 32P-labeled P450 side-chain cleavage, P450 17-α-hydroxylase, and P450c21 complementary DNA probes. We detected heterozygous germline mutations (exon 7, Val 281Leu) in two patients, one with a cortisol-producing adenoma and the other with an androgen-secreting adrenocortical carcinoma. A somatic, heterozygous microdeletion was found in exon 3 of one aldosterone-producing adenoma. The P450c21 gene expression correlated with the clinical phenotype of the tumor, with low P450c21 messenger RNA expression in nonfunctional adenomas (18.8%, 1.5%) compared with high P450c21 expression in aldosterone- and cortisol-producing adenomas (84 ± 8% and 101 ± 4%, respectively, vs. normal adrenals, 100 ± 10%). In conclusion, the prevalence of heterozygous germline mutations in the CYP21B gene was higher in patients with adrenocortical tumors (11%; 95% confidence interval, 1–34%) than in the general European population (2%; 95% confidence interval, 1.93–2.06%), but this difference is questionable because of the low number of subjects in our series. The pathophysiological significance of this finding in the presence of one normal CYP21B gene seems to be low, suggesting that 21-hydroxylase deficiency is not a major predisposing factor for adrenal tumor formation.

Boron (B) is a micronutrient for vascular plants, and B deficiency has been recognized as a limiting factor for crop production in many areas worldwide. To gain a better insight into the adaptability mechanism of plant responses to B starvation, an Arabidopsis whole genome Affymetrix GeneChip was used to evaluate global gene expression alterations in response to short- and long-term B deficiency stress. A large number of B deficiency-responsive genes were identified and grouped by their functions. Genes linked to jasmonic acid (JA) showed the most prominent response under B deficiency. The transcripts for biosynthesis and regulation of JA were constantly induced during short- and long-term B deficiency stress. A set of well-known JA-dependent process and responsive genes showed the same expression profile. This suggested that JA could be a pivotal player in the integration of adaptive responses to B deficiency stress. Moreover, other functional groups of B deficiency-responsive genes (including various encoding the biosynthesis of antioxidants, the basic components of Ca2+ signalling, protein kinases, cell wall-modifying enzymes and proteins, H+-ATPase, K+ transporters, and a set of enzymes involved in central metabolism and cellular growth) were also observed, and their physiological roles under B deficiency stress are discussed. These results provide some information for a better understanding of plant-adaptive responses to B deficiency stress and potential strategies to improve B efficiency in crops

Abstract Vitamin D, via its receptor (VDR), inhibits the hormone secretion and proliferation of parathyroid cells. Vitamin D deficiency and reduced parathyroid VDR expression has been associated with development of hyperparathyroidism (HPT) secondary to uremia. VDR polymorphisms may influence VDR messenger RNA (mRNA) levels and have been coupled to an increased risk of parathyroid adenoma of primary HPT. VDR mRNA relative to glyceraldehyde-3-phosphate dehydrogenase mRNA levels were determined by RNase protection assay in 42 single parathyroid adenomas of patients with primary HPT, 23 hyperplastic glands of eight patients with uremic HPT, and 15 normal human parathyroid glands. The adenomas and hyperplasias demonstrated similar VDR mRNA levels, which were reduced (42 ± 2.8% and 44 ± 4.0%) compared with the normal glands (P < 0.0001). Comparison of parathyroid adenoma with a normal-sized parathyroid gland of the same individual (n = 3 pairs) showed a 20–58% reduction in the tumor. Nodularly enlarged glands represent a more advanced form of secondary HPT and showed greater reduction in the VDR mRNA levels than the diffusely enlarged glands (P < 0.005). The reduced VDR expression is likely to impair the 1,25(OH)2D3-mediated control of parathyroid functions, and to be of importance for the pathogenesis of not only uremic but also primary HPT. Circulating factors like calcium, PTH, and 1,25(OH)2D3 seem to be less likely candidates mediating the decreased VDR gene expression in HPT.

The use of boron preparations (borax and boric acid) in medicine began long before their isolation in pure form. The mineral water of boron-containing sources has been historically used to treat skin diseases, to wash eyes, to disinfect wounds, etc. Also, what is of interest in the context of this article, boron-containing waters were used as calming, anti- anxiety, anticonvulsant and sleep-promoting remedy. In 1777, boric acid was first isolated from the mineral water of a healing spring source in Florence. Historically, first name of this compound was sal sedativum (“soothing salt”). However, the discovery of boron toxicity led to the cessation of its internal use. In recent decades, it has been found that boron is a microelement necessary for many metabolic processes in the body. It affects memory, cognitive functions, anxiety level, sleep, mood, regulates calcium and magnesium exchange, metabolism of vitamin D and sex steroids. It has been shown that some cases of treatment resistance to standard therapy, for example in epilepsy, anxiety and depression, are related to boron deficiency. In this regard, interest in the use of boron preparations in psychiatry and neurology, but in much smaller doses and on new scientific grounds, flared up again.

17β-Hydroxysteroid dehydrogenase-3 (17βHSD3) deficiency is an autosomal recessive form of male pseudohermaphroditism caused by mutations in the HSD17B3 gene. In a nationwide study on male pseudohermaphroditism among all pediatric endocrinologists and clinical geneticists in The Netherlands, 18 17βHSD3-deficient index cases were identified, 12 of whom initially had received the tentative diagnosis androgen insensitivity syndrome (AIS). The phenotypes and genotypes of these patients were studied. Endocrine diagnostic methods were evaluated in comparison to mutation analysis of the HSD17B3 gene. RT-PCR studies were performed on testicular ribonucleic acid of patients homozygous for two different splice site mutations. The minimal incidence of 17βHSD3 deficiency in The Netherlands and the corresponding carrier frequency were calculated. Haplotype analysis of the chromosomal region of the HSD17B3 gene in Europeans, North Americans, Latin Americans, Australians, and Arabs was used to establish whether recurrent identical mutations were ancient or had repeatedly occurred de novo. In genotypically identical cases, phenotypic variation for external sexual development was observed. Gonadotropin-stimulated serum testosterone/androstenedione ratios in 17βHSD3-deficient patients were discriminative in all cases and did not overlap with ratios in normal controls or with ratios in AIS patients. In all investigated patients both HSD17B3 alleles were mutated. The intronic mutations 325+ 4;A→T and 655–1;G→A disrupted normal splicing, but a small amount of wild-type messenger ribonucleic acid was still made in patients homozygous for 655–1;G→A. The minimal incidence of 17βHSD3 deficiency in The Netherlands was shown to be 1:147,000, with a heterozygote frequency of 1:135. At least 4 mutations, 325 + 4;A→T, N74T, 655–1;G→A, and R80Q, found worldwide, appeared to be ancient and originating from genetic founders. Their dispersion could be reconstructed through historical analysis. The HSD17B3 gene mutations 326–1;G→C and P282L were de novo mutations. 17βHSD3 deficiency can be reliably diagnosed by endocrine evaluation and mutation analysis. Phenotypic variation can occur between families with the same homozygous mutations. The incidence of 17βHSD3 deficiency is 0.65 times the incidence of AIS, which is thought to be the most frequent known cause of male pseudohermaphroditism without dysgenic gonads. A global inventory of affected cases demonstrated the ancient origin of at least four mutations. The mutational history of this genetic locus offers views into human diversity and disease, provided by national and international collaboration.

The catalase enzyme decomposes the toxic concentrations of hydrogen peroxide into oxygen and water. Hydrogen peroxide is a highly reactive small molecule and its excessive concentration may cause significant damages to proteins, deoxyribonucleic acid, ribonucleic acid and lipids. Acatalasemia refers to inherited deficiency of the catalase enzyme. In this review the authors discuss the possible role of the human catalase enzyme, the metabolism of hydrogen peroxide, and the phenomenon of hydrogen peroxide paradox. In addition, they review data obtained from Hungarian acatalasemic patients indicating an increased frequency of type 2 diabetes mellitus, especially in female patients, and an early onset of type 2 diabetes in these patients. There are 10 catalase gene variants which appear to be responsible for decreased blood catalase activity in acatalasemic patients with type 2 diabetes. It is assumed that low levels of blood catalase may cause an increased concentration of hydrogen peroxide which may contribute to the pathogenesis of type 2 diabetes mellitus. Orv. Hetil., 2015, 156(10), 393–398.

Pregnancy and Folic Acid. Pregnancy is the most important period in life of every woman, partially for the number of physiological adaptations she is going through, partially for the expectance of new life. In addition, pregnancy is the ?critical window? for development later in childhood, as a period of foetal programming during which nutrition plays one of crucial roles. Despite the general belief that nutrition through pregnancy is adequate and characterized by better nutritional habits, a number of studies do not corroborate this belief. Role of Folic Acid. An adequate folate blood level is necessary for normal cell growth, synthesis of several compounds including deoxyribonucleic acid and ribonucleic acid, proper brain and neurologic functions; it is included in the regulation of homocysteine level, and closely related to the vitamin B12 metabolism. Folate deficiency in pregnancy is related to neural tube defects, other neurological disorders, preterm delivery and low birth weight. Food sources. A correlation between folate and the prevention of broad spectrum of chronic diseases has been confirmed. Emerging evidence from the epigenetic studies is now bringing even more light on the level of significance of folic acid. A wide range of plant and animal foods are the natural sources of folate; liver, yeast, mushrooms, and green leafy vegetables being the most significant. Different ways of food preparation influence the folate stability and its bioavailability varies from 25 to 50% from foods, 85% from enriched foods or 100% from supplements. Conclusion. A great amount of scientific results has led to official recommendations for folic acid supplementation in pregnant women as well as in a number of obligatory or voluntary fortification programmes in order to prevent the folate deficiency on the level of different population groups. Nevertheless, there must be a certain level of precaution for elderly because folate can mask the vitamin B12 deficiency with possible fatal outcomes.

The aim of the present study was to perform kidney messenger ribonucleic acid (mRNA) analysis in normotensive, Hannover Sprague–Dawley (HanSD) rats and hypertensive, Ren-2 renin transgenic rats (TGR) after doxorubicin-induced heart failure (HF) with specific focus on genes that are implicated in the pathophysiology of HF-associated cardiorenal syndrome. We found that in both strains renin and angiotensin-converting enzyme mRNA expressions were upregulated indicating that the vasoconstrictor axis of the renin–angiotensin system was activated. We found that pre-proendothelin-1, endothelin-converting enzyme type 1 and endothelin type A receptor mRNA expressions were upregulated in HanSD rats, but not in TGR, suggesting the activation of endothelin system in HanSD rats, but not in TGR. We found that mRNA expression of cytochrome P-450 subfamily 2C23 was downregulated in TGR and not in HanSD rats, suggesting the deficiency in the intrarenal cytochrome P450-dependent pathway of arachidonic acid metabolism in TGR. These results should be the basis for future studies evaluating the pathophysiology of cardiorenal syndrome secondary to chemotherapy-induced HF in order to potentially develop new therapeutic approaches.

Boron is an essential element for plants, animals, and humans. Its deficiency in plants may result in reduced growth rates, yield loss, and even death. At the same time, excess of boron is toxic for both plants and living organisms. Boron is important for steroid hormones production, vitamin D and minerals metabolism, formation of bone tissue, and affects estrogen and testosterone levels. The primary source of boron for humans and other living organisms is plant-origin food. The richest ones are fruits and nuts. High concentrations of boron are found in raisins (22 mg/kg), peanuts (17 mg/kg), peanut butter (14,5 mg/kg). In the agriculture the boron monitoring in soils and water irrigation is particularly important because this element is crucial for plant growth Boron deficiency has a drastic effect on fruit quality and yield, even when there are only mild or moderate foliar symptoms. The main source of boron for plants is soil and water. Quantitative determination of boron in soil extracts can be performed using spectrophotometric, potentiometric, chromatographic, atomic absorption spectrophotometric, and inductively coupled plasma techniques. The most popular are inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). These methods are described in the appropriate standards PN-EN ISO 11885:2009 and PN-EN ISO 17294–1:2007. Boric acid is known to form complexes through esterification reactions with hydroxy-group in molecules of amino- and carboxylic acids, carbohydrates, nucleotides and vitamins that can be used for boron extraction from soils. Partial esterification results in monoesters (1:1 complex) and complete esterification leads to the bicyclic diester (1:2 complex). In present research the tetrafluoroborate selective sensor applicable for fluoroborate formation reaction monitoring was used as an analytical tool for the investigation of an impact of soil extraction procedure for boron analysis. The investigation of alternative soil boron extraction procedures using α-hydroxy acids (and other cis-diol containing compounds) and subsequent quantitative analysis of boron by kinetic-potentiometric monitoring of fluoroborate formation rate with use of previously developed [BF4]¯-selective electrode have been performed. The kinetics of complex destruction under fluoride containing acidified media by means of kinetic-potentiometric analysis has been investigated. The possible boron losses during its extraction from soils have been checked.

Micronutrients perform specific and essential functions in plant metabolism, and their deficiency may lead to metabolic disturbances that affect coffee production and quality beverage. In Brazil, the B, Cu, and Zn are the main micronutrients, and these are provided by soil or foliar fertilization, frequently with low recovery efficiency. This work objected verifying the feasibility of supplying of B, Cu, and Zn via insertion of tablets in the orthotropic branch of Coffea arabica, as well as to evaluate the coffee plant response in terms of productivity and quality of the beverage. Adult plants received B, Cu, and Zn, each micronutrient alone or combined with the other two, by foliar fertilization or by tablets inserted in the trunk base. The productivity, cupping quality, and some chemical indicators of beans quality were evaluated in two crop seasons. Boron, copper, and zinc supplied by foliar spray or solid injections in the trunk influenced the chemical composition and quality of the coffee beans, characterized by the cupping test and the levels of caffeine, trigonelline, sucrose, glucose, arabinose, mannose, 3-caffeoylquinic acid, 5-caffeoylquinic acid, polyphenol oxidase activity, and total phenolic compounds. Copper and zinc were equivalent in either form of supply regarding the production and quality of coffee.

SMA (Spinal muscular atrophies) are category of hereditary inflammation in the funiculars and lower brain stem, tissue fatigue, and degeneration characterized by motor neuron failure. The analytic and genetic phenotypes incorporate a diverse continuum distinguished depending on age of onset, tissue participation arrangement, and inheritance arrangement. Rapid advancements in genetic science have expedite the discovery of causative genes over the past few years, and provide significant access in awareness the biochemical and neurological basis of Spinal muscular atrophies and insights into the motor neurons' selective deficiency. Popular path physiological topics include Ribonucleic Acid metabolism and splicing abnormalities, axonal transmission, and motor neurons' advancement and communication. These also collectively revealed possible innovative prevention methods and comprehensive attempts are what benefits does the company offer? Although a range of promising therapeutic therapies for Spinal muscular atrophies is emerging, it is essential to identify therapeutic windows and establish responsive and appropriate biomarkers to promote future analytic trial success. This research offers a description of Spinal muscular atrophies' logical manifestations and genetics. It discusses recent advancements in learning—mechanisms for the pathogenesis of inflammation and new treatment methods.

We identified two homozygous missense mutations in the human type II 3β-hydroxysteroid dehydrogenase (3βHSD) gene, the first in codon 6 of exon II [CTT (Leu) to TTT (Phe)] in a male infant with hyperpigmented scrotum and hypospadias, raised as a male and no apparent salt-wasting since neonatal age, and the second in codon 259 of exon IV [ACG (Thr) to ATG (Met)] in a male pseudohermaphrodite with labial scrotal folds, microphallus, chordee, and fourth degree hypospadias, raised as a female and with salt-wasting disorder since neonatal age. In vitro transient expression of mutant type II 3βHSD complementary DNAs of L6F, T259M, as well as T259R for comparison was examined by a site-directed mutagenesis and transfection of construct into COS-1 and COS-7 cells. Northern blot analysis revealed expression of similar amounts of type II 3βHSD messenger ribonucleic acid from the COS-1 cells transfected by L6F, T259M, T259R, and wild-type (WT) complementary DNAs. Western immunoblot analysis revealed a similar amount of L6F mutant protein compared to WT enzyme from COS-1 cells, but neither L6F from COS-7 cells nor T259M or T259R mutant protein in COS-1 or COS-7 cells was detectable. Enzyme activity in intact COS-1 cells using 1 μmol/L pregnenolone as substrate in the medium after 6 h revealed relative conversion rates of pregnenolone to progesterone of 46% by WT enzyme, 22% by L6F enzyme, and 8% by T259M enzyme and less than 4% activity by T259R enzyme. Using 1 μmol/L dehydroepiandrosterone as substrate, the relative conversion rate of dehydroepiandrosterone to androstenedione after 6 was 89% by WT enzyme, 35% by L6F enzyme, 5.1% by T259M enzyme and no activity by T259R enzyme. However, the L6F mutant 3βHSD activity, despite its demonstration in the intact cells, was not detected in homogenates of COS-1 cells or in immunoblots of COS-7 cells, suggestive of the relatively unstable nature of this protein in vitro, possibly attributable to the decreased 3βHSD activity. In the case of T259M and T259R mutations, consistently undetectable proteins in both COS cells despite detectable messenger ribonucleic acids indicate severely labile proteins resulting in either no or very little enzyme activity, and these data further substantiate the deleterious effect of a structural change in this predicted putative steroid-binding domain of the gene. In conclusion, the findings of the in vitro study of mutant type II 3βHSD enzyme activities correlated with a less severe clinical phenotype of nonsalt-wasting and a lesser degree of genital ambiguity in the patient with homozygous L6F mutation compared to a more severe clinical phenotype of salt-wasting and severe degree of genital ambiguity in the patient with homozygous T259M mutation in the gene.

Albright hereditary osteodystrophy (AHO) is a genetic disorder characterized by short stature, skeletal defects, and obesity. Within AHO kindreds, some affected family members have only the somatic features of AHO [pseudopseudohypoparathyroidism (PPHP)], whereas others have these features in association with resistance to multiple hormones that stimulate adenylyl cyclase within their target tissues[ pseudohypoparathyroidism type Ia (PHP Ia)]. Affected members of most AHO kindreds (both those with PPHP and those with PHP Ia) have a partial deficiency of Gsα, the α-subunit of the G protein that couples receptors to adenylyl cyclase stimulation, and in a number of cases heterozygous loss of function mutations within the Gsα gene (GNAS1) have been identified. Using PCR with the attachment of a high melting domain (GC-clamp) and temperature gradient gel electrophoresis, two novel heterozygous frameshift mutations within GNAS1 were found in two AHO kindreds. In one kindred all affected members (both PHP Ia and PPHP) had a heterozygous 2-bp deletion in exon 8, whereas in the second kindred a heterozygous 2-bp deletion in exon 4 was identified in all affected members examined. In both cases the frameshift encoded a premature termination codon several codons downstream of the deletion. In the latter kindred affected members were previously shown to have decreased levels of GNAS1 messenger ribonucleic acid expression. These results further underscore the genetic heterogeneity of AHO and provides further evidence that PHP Ia and PPHP are two clinical presentations of a common genetic defect. Serial measurements of thyroid function in members of kindred 1 indicate that TSH resistance progresses with age and becomes more evident after the first year of life.

We present an in vivo and in vitro study of congenital adrenal hyperplasia in a patient with 11β-hydroxylase deficiency. Sequencing of the CYP11B1 gene showed two new base substitutions, a conservative 954 G→C transversion at the last base of exon 5 (T318T), and a IVS8 + 4A→G transition in intron 8. In addition, two polymorphisms were found in exons 1 and 2. The genetically female patient was raised as a male because of severe pseudohermaphroditism. Glucocorticoid-suppressive treatment encountered difficulties in equilibration and compliance, resulting in uncontrolled hypertension with pronounced hypertrophic cardiomyopathy. At 42 yr of age the occurrence of central retinal vein occlusion with permanent loss of left eye vision led to the decision to perform bilateral laparoscopic adrenalectomy. Surgery was followed by normalization of blood pressure and good compliance with glucocorticoid and androgen substitutive therapies. In vitro, adrenal cells in culture and isolated mitochondria showed extremely low 11β-hydroxylase activity. Analysis of adrenal CYP11B1 messenger ribonucleic acid (mRNA) by RT-PCR and sequencing showed the expression of a shorter mRNA that lacked exon 8 and did not contain either the exon 5 mutation or the exon 1 and 2 polymorphisms. This suggested that one CYP11B1 allele carried the intron 8 mutation, responsible for skipping exon 8. The other allele carried the exon 5 mutation, and its mRNA was not detectable. Western blot analysis showed weak expression of a shorter CYP11B immunoreactive band of 43 kDa, consistent with truncation of exon 8. Thus, bilateral adrenalectomy in this patient allowed effective treatment of severe hypertension and helped in understanding the mechanisms and physiopathological consequences of two novel mutations of CYP11B1.

Twenty-kilodalton human GH (20K), which is one of the human GH (hGH) variants, is thought to be produced by alternative premessenger ribonucleic acid splicing. However, its physiological role is still unclear due to the lack of a specific assay. We have measured serum 20K and 22-kDa hGH (22K) by specific ELISAs to investigate the physiological role of 20K in children. The subjects were 162 normal children, aged 1 month to 20 yr; 12 patients with GH deficiency (GHD), aged 11 months to 13 yr; 57 children with non-GHD short stature, aged 2–17 yr; and 13 girls with Turner’s syndrome, aged 5 months to 15 yr. Samples were collected at random from normal children and were collected after hGH provocative tests and 3-h nocturnal sleep from GHD, non-GHD short stature, and Turner’s syndrome children. The mean basal serum concentrations of 22K and 20K were 2.4 ± 2.8 ng/mL and 152.3 ± 184.0 pg/mL in normal boys and 2.5 ± 3.1 ng/mL and 130.6 ± 171.5 pg/mL in normal girls, respectively. The percentages of 20K (%20K) were 5.8 ± 2.1% and 6.0 ± 3.2% in 83 normal boys and 79 normal girls, respectively. There was no significant difference in %20K either among ages or between the prepubertal stage and the pubertal stage in normal boys and girls. The mean %20K values in basal samples of provocative tests in 12 patients with GHD, non-GHD short stature, and Turner’s syndrome were 6.5 ± 2.4%, 6.5 ± 3.8%, and 5.9 ± 3.2%, respectively. There was no significant difference in %20K among normal children and these growth disorders, and there was no significant difference in %20K throughout the hGH provocative tests and 3-h nocturnal sleep in these growth disorders. There was also no significant correlation between the percentage of 20K and the height sd score or body mass index in either normal children or subjects with these growth disorders. In conclusion, the %20K is constant, regardless of age, sex, puberty, height sd score, body mass index, and GH secretion status. The regulation of serum 20K levels remains to be established.

Introduction Methods Resuts Discussion Conclusions Acknowledgments Authors' contributions Competing interests Ethical approval References Effect of Methotrexate and Omega-3 Combination on Cytogenetic Changes of Bone Marrow and Some Enzymatic Antioxidants: An Experimental Study Inaam N. Ali1, Muthana M. Awad2, Alaa S. Mahmood2,* 1 Water and Environment Directorate, Ministry of Sciences and Technology, Baghdad, Iraq 2 Department of Biology, College of Science, University of Anbar, Anbar, Iraq * Corresponding author: A. S. Mahmood (alaashm91@gmail.com) Abstract: Objective: To assess the effect of methotrexate and omega-3 combination on cytogenetic changes of bone marrow and activities of some enzymatic antioxidants. Methods: Fifty-six mature male Wistar rats were divided into two experimental groups and a control group. The first experimental group was sub-divided into three sub-groups depending on the concentration of methotrexate (MTX): X1 (0.05 mg/kg MTX), X2 (0.125 mg/kg MTX) and X3 (0.250 mg/kg MTX), which were given intraperitoneally on a weekly basis for eight weeks. The second experimental group (MTX and omega-3 group) was also sub-divided into three sub-groups (Y1, Y2 and Y3), which were injected intraperitoneally with 0.05, 0.125 and 0.25 mg/kg MTX, respectively, weekly for eight weeks accompanied by the oral administration of 300 mg/kg omega-3. The rats of the control group were given distilled water. The enzymatic activity of catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR) were measured in the sera of rats. In addition, the mitotic index (MI) and chromosomal aberrations of bone marrow were also studied. Results: MTX resulted in a significant decrease in the activities of CAT, SOD and GR compared to the controls. It also increased the MI and chromosomal aberrations of rat bone marrows. On the other hand, omega-3 significantly increased the activities of the investigated enzymatic antioxidants and reduced the MI and chromosomal aberrations in treated mice when given in combination with MTX. Conclusions: MTX has a genotoxic effect on the bone marrow by increasing the MI and all types of chromosomal aberrations and decreasing the enzymatic activity of CAT, SOD and GR. The addition of omega-3 can lead to a protective effect by reducing the toxic and mutagenic effects of MTX. Keywords: Methotrexate, Omega-3, Antioxidant, Wistar rat, Chromosomal aberration, Mitotic index 1. Introduction Methotrexate (MTX) is a folic acid antagonist because of their chemical similarity [1]. Vezmar et al. [2] showed that MTX affects the synthesis of nucleic acids deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) by interfering with the biosynthesis of thymine and purines. It also directly affects the rapidly dividing and intact cells, especially those in the mucous membranes of the mouth, intestine and bone marrow [3]. Omega-3 is a type of unsaturated fats, which are classified as essential fatty acids that cannot be manufactured by the body and should be taken with food [4]. Sources of omega-3 include fish oils, such as salmon, sardines and tuna, as well as soybeans, walnuts, raisins and linseed, almonds and olive oils [5]. Omega-3 is used in the prevention of a number of diseases such as rheumatoid arthritis, ulcerative colitis, asthma, atherosclerosis, cancer, and cardiovascular diseases [6]. A large amount of evidence indicates that omega-3 fatty acids have significant health benefits, including anti-inflammatory and antioxidant properties besides their effect on blood cholesterol levels [7]. Antioxidants retard the oxidation process by different mechanisms such as the removal of free radicals [8]. Enzymatic antioxidants include catalase (CAT), which is the first line of defense in the cell that removes hydrogen peroxide formed during biological processes by converting it into an aldehyde, and superoxide dismutase (SOD). There are three major families of SOD enzymes: manganese SOD (Mn-SOD) in the mitochondria and peroxisomes, iron SOD (Fe-SOD) in prokaryote cells and copper/zinc SOD (Cu-Zn SOD) in the cytoplasm of eukaryote cells [9]. Therefore, changes in the metal co-factors (manganese, iron, copper and zinc) can alter the effectiveness of SOD and may lead to diseases as a result of oxidative stress [10]. Glutathione reductase (GR) is also an enzymatic antioxidant that converts the oxidized glutathione to the reduced glutathione in the presence of NADPH, which is oxidized to NADP [11]. Therefore, the aim of the present study was to assess the effects of MTX and omega-3 on the cytogenetic changes of bone marrow as well as the activities of CAT, SOD and GR enzymatic antioxidants in male rats. 2. Method 2.1. Laboratory animals and experimental design Fifty-six mature male Wistar rats (Rattus norvegicus), aged 10–12 weeks old and weighing 250–300 gm, were used in the present study. The rats were kept in separate cages, with natural 13- hour light and 11-hour dark periods in a contamination-free environment with a controlled temperature (28.0 ± 1.0°C). In addition, rats were maintained on a standard diet and tap water ad libitum. The rats were randomly allocated to two experimental groups and a control group. The first experimental group (MTX group) included 24 rats injected intraperitoneally with different MTX dilutions with distilled water [12]. It was sub-divided into three sub-groups (eight rats per sub-group) according to MTX concentration as follows: X1 (0.05 mg/kg MTX), X2 (0.125mg/kg MTX) and X3 (0.25 mg/kg MTX). All rats were given a single dose of the specified MTX concentration weekly for eight weeks. The second experimental group (MTX and omega-3 group) included 24 rats allocated to three sub-groups (Y1, Y2 and Y3), which were injected intraperitoneally with 0.05, 0.125 and 0.25 mg/kg MTX, respectively, weekly for eight weeks accompanied by the oral administration of 300 mg/kg omega-3. The control group included eight rats that were intraperitoneally injected with distilled water and given a single dose of distilled water orally weekly for eight weeks. 2.2. Blood collection and processing After the end of the dosing period, 5 ml of blood were withdrawn from the heart (by cardiac puncture) using a 5 cc disposable syringe. The collected blood was immediately poured into a clean sterile screw-capped tube (plain tube) and left for coagulation in a water bath at 37°C for 15 minutes. After coagulation of blood, the plain tube was centrifuged for 5 minutes at 1500 rpm. Then the samples were stored at -20°C for subsequent analysis. 2.3. Measurement of the activity of antioxidant enzymes The antioxidant activities of CAT, SOD and GR were measured using enzyme-linked immunosorbent assay kits purchased from Kamiya Biomedical Company (Seattle, WA, US), according to the manufacturer's instructions. 2.4. Cytogenetic study of bone marrow Rats were killed by cervical dislocation, and their hip bones were cleaned from surrounding muscles and then dissected by cutting both ends of the bone. Five milliliters of physiological buffered saline were injected inside the bone to withdraw bone marrow into a test tube. Tubes were centrifuged at 2000 rpm/10 minutes. The supernatant was then removed, and 10 ml of KCL solution (0.075 M) were added to the sediment. The mixture was then incubated at 37 °C in a water bath for 30 minutes, with shaking from time to time. The tubes were then centrifuged at 2000rpm/10 minutes to remove the supernatant. However, 5 ml of a freshly prepared fixative solution (methanol: glacial acetic acid 1:3) were added gradually in the form of droplets into the inner wall of the tube with constant mixing. After that, the tubes were placed at 4 °C for half an hour to fix the cells. This process was repeated for three times, and the cells were then suspended in 2 ml of the fixative solution. The tubes were centrifuged at 2000 rpm for 5 minutes, and the supernatant was then removed while the cells were re-suspended in 1-2 ml of cold fixative solution. After shaking the tubes, 4–5 drops were then taken from each tube onto a clean slide from a height of about three feet to provide an opportunity for the cells and nuclei to spread well. The slides were stained with acridine orange solution (0.01%) for 4–5 minutes, incubated in Sorensen’s buffer (0.06M, pH 6.5) for a minute. and then examined using a fluorescence microscope Olympus BX 51 America at a wavelength of 450–500 nm [13, 14]. A total of 1000 cells were examined, and both dividing and non-dividing cells were calculated [13]. Mitotic index (MI) was calculated according to the following formula [13]: MI= No. of dividing cells / 1000 × 100 2.5. Analysis of chromosomal aberrations of bone marrow cells A total of 1000 dividing cells were examined on the stained slides under a fluorescence microscope at a wavelength of 45–500 nm. The examined cells were at the first metaphase of the mitotic division, where chromosomal aberrations are clear and can be easily seen [13]. 2.6. Statistical analysis Data were analyzed using the Statistical Analysis System (SAS®) software, version 9.1 (Cary, NC, USA) [15]. Effects were expressed as mean ± standard error (SE) and statistically compared using a completely randomized design analysis of variance and least significant differences. Differences at P values <5 were considered statistically significant. 3. Results 3.1. Effects of MTX and MTX-omega-3 combination on antioxidant enzymatic activities Table (1) shows significantly lower SOD activities among rats treated with MTX or MTX-omega-3 compared to controls. Moreover, sera of rats receiving relatively high doses of MTX (sub-groups X2 and X3) showed the lowest enzymatic activities of 4.29 ± 0.01 IU and 3.93 ± 0.11 IU, respectively. On the other hand, CAT activity differed significantly between treated and control rats as well as among treated rats themselves, In this respect, the controls showed the highest activity of 39.38 ±0.02 IU, while those receiving the highest MTX concentration, either alone or in combination with omega-3 (sub-groups X3 and Y3), showed the lowest activities of 30.97 ± 0.03 IU and 32.12± 0.06 IU, respectively. Regarding GR activity, control rats showed a higher activity of 53.09± 0.05 IU compared to treated ones; however, the differences in GR activities in rats given low doses of MTX, either alone or in combination with omega-3 (sub-groups X1 and Y1), were not statistically significant. On the other hand, rats in sub-groups X3 and Y3 showed the lowest GR activities of 34.59 ± 0.63 IU and 37.15 ±0.01, respectively, with statistically significant differences from other sub-groups. 3.2. Effects of MTX and MTX-omega-3 combination on mitotic index of bone marrow cells Figure (1) shows a significant decrease in the MI in all treated groups compared to control. In addition, there was a reverse association between MTX concentration and MI, where rats treated with the highest dose of MTX (sub-group X3) showed a significant decrease in MI compared to all other treated rat sub-groups. In addition, rats in sub-groups treated with MTX and omega-3 (sub-groups Y1, Y2 and Y3) showed a significant increase in MI compared to their counterpart rats receiving MTX only. Table 1. Activity of antioxidant enzymes in rats treated with MTX and MTX-omega-3 Group Enzymatic activity (mean± SE) SOD (IU) CAT (IU) GR (µmol) Control 6.41±0.02 a 39.38±0.02 a 53.09±0.05 a X1 (0.05 mg MTX/ kg) 5.33±0.01 b 37.81±0.01 c 51.12±0.06 a Y1 (0.05 mg MTX + 300 mg omega-3/ kg) 6.08±0.04 a 38.40±0.02 b 51.97±0.03 a X2 (0.125 mg MTX/ kg) 4.29±0.01 cd 33.13±0.01 e 42.34±0.03 b Y2 (0.125 mg MTX + 300 mg omega-3/ kg) 4.99±0.40 b 36.68±0.02 d 43.02±3.04 b X3 (0.25 mg MTX/ kg) 3.93±0.11 d 30.97±0.03 g 34.59±0.63 c Y3 (0.25 mg MTX + 300 mg omega-3/ kg) 4.47±0.02 c 32.12±0.06 f 37.15±0.01 c SE, Standard error; IU, international unit; SOD, superoxide dismutase; CAT, catalase; GR, glutathione reductase; *statistically significant at P < 0.05; **statistically significant at P < 0.01. Means with different letters within the same column showed a statistically significant difference. 3.3. Effects of MTX and MTX-omega-3 combination on chromosomal aberrations of bone marrow cells Rats receiving higher concentrations of MTX (sub-group X3) showed a significant increase in all types of chromosomal aberrations, i.e., chromatid gaps, chromosome gaps, chromatid breaks, chromosome breaks, deletions and simple fragments (Figure 2 and Table 2) than those of the control group or other treated sub-groups. All rats treated with MTX-omega-3 combination showed a significant decrease in almost all types of chromosomal aberrations compared to their counterpart rats receiving MTX alone (Table 2). Figure 1. Effect of MTX and MTX-omega-3 on the MI of bone marrow cells of treated rats compared to the controls. The groups X1 (0.05 MTX), X2 (0.125 MTX) and X3 (0.250 MTX) were compared to the control group, while the groups Y1 (0.05 MTX+ omega-3), Y2 (0.125 MTX+ omega-3) and Y3 (0.25 MTX+ omega-3) were compared to X1, X2 and X3, respectively. Figure 2. Effect of MTX and MTX-omega-3 on chromosomal aberration as seen under fluorescence microscope after staining with acridine orange: (1) a simple fragment; (2) a chromatid gap; (3) a chromosomal gap (A) and a chromosomal break (B). 4. Discussion The present experiment reveals that the addition of omega-3 to MTX alleviates its effects on the activities of the antioxidant enzymes CAT, SOD and GR, and decreases the MI as well as all types of chromosomal aberrations in the bone marrow cells. Daham et al. [16] showed that the decline in antioxidants associated with chemotherapy is attributed to the increase in lipid peroxidation caused by these kinds of drugs, which increase the level of free radicals. In addition, Weijl et al. [17] showed that some chemotherapeutic drugs have a negative effect on the antioxidant levels such as GR, whose activity decreases as a result of its involvement in many cellular processes such as cell defenses against the toxicity of some compounds. Al-Dalawy et al. [18] found that the decrease in the level of SOD is an evidence of its increased activity due to the increased release of free radicals. MTX causes an increase in the release of free radicals, including the OH radical that causes direct damage to DNA [16]. Al-Helaly [19] showed that the amount of food taken has an effect on antioxidants, where nutritional deficiency decreases the antioxidant levels, thus increasing free radicals that cause damage to DNA. Table 2. Chromosomal aberrations of bone marrow cells in rats treated with MTX and MTX-omega-3 Group Type of chromosomal aberration(mean ± SE) Chromatid gap Chromosome Gap Chromatid breaks Chromosome breaks Deletion Simple Fragments Chromosomal aberration (%) Control 1.33±0.33 e 0.00±0.00 e 1.67±0.33 c 0.33±0.15 c 0.00±0.00 0.67±0.33 cd 0.04±0.005 f X1 2.75±0.47 cd 1.50±0.28 cd 2.50±0.64 bc 1.00±0.41 bc 0.50±0.28 bc 0.75±0.25 bcd 0.09±0.02 de Y1 1.75±0.47 de 0.75±0.25 de 1.50±0.28 c 1.00±0.00 bc 0.75±0.25 abc 0.75±0.25 abc 0.065±0.005 ef X2 4.67±0.33 b 2.67±0.33 ab 2.67±0.33 bc 1.67±0.33 ab 0.67±0.33 abc 1.67±0.33 ab 0.14±0.006 bc Y2 3.00±0.00 c 2.00±0.00 bc 3.00±0.057 bc 1.33±0.33 b 0.67±0.33 abc 0.33±0.15 d 0.106±0.003 cd X3 6.80±0.37 a 3.00±0.31 a 4.60±0.74 a 2.40±0.24 a 1.40±0.24 a 1.80±0.37 a 0.20±0.017 a Y3 5.60±0.40 ab 2.40±0.24 ab 3.60±0.24 ab 1.80±0.20 ab 1.20±0.20 ab 1.40±0.24 abc 0.16±0.003 b LSD 1.231** 0.814** 0.602** 0.841** 0.774* 0.941** 3.499* SE, Standard error; * statistically significant at P < 0.05; ** statistically significant at P < 0.01. Means with different letters within the same column showed a statistically significant difference. X1 (0.05 mg MTX/ kg); X2 (0.125 mg MTX/ kg); X3 (0.25 mg MTX/ kg); Y1 (0.05 mg MTX + 300 mg omega-3/ kg); Y2 (0.125 mg MTX + 300 mg omega-3/ kg); Y3 (0.25 mg MTX + 300 mg omega-3/ kg). In the present study, the intraperitoneal administration of MTX to rats also caused a decrease in the MI of bone marrow and a significant increase in the rate of abnormal chromosomal aberration compared to the control rats. This finding is consistent with those reported previously [20], [21]. The effect of MTX can be attributed to its ability to interfere with the genetic material, leading to the appearance of toxic and mutagenic consequences. Rushworth et al. [22] reported that MTX leads to a lack of dihydrofolate reductase, which is the key to the growth and cell division processes. This, in turn, leads to a reduction of the nucleotides involved in the building of DNA and, therefore, to a stop or obstruction of the repair mechanisms of the damaged DNA. In addition, Wong and Choi [23] concluded that MTX inhibits the action of enzymes controlling the purine metabolism, which leads to the accumulation of adenosine in addition to the damage of the molecule itself and to the occurrence of chromosomal aberrations. Jafer et al. [24] reported the ability of MTX to induce chromosomal aberration in humans or animals by preventing the repair of DNA and affecting the proteins found in chromosomes. These findings were also confirmed by Hussain et al. [25], who found that MTX causes an increase in chromosomal aberrations. In the present study, the MI showed a significant increase in rat sub-groups treated with MTX-omega-3 combination, but there was a decrease in the rate of chromosomal aberration, which confirms the role of omega-3 unsaturated fatty acids in protecting the cell from the impact of free radicals [26], [27]. Attia and Nasr [28] reported the antioxidant effect of omega-3, which was attributed to the reduction in lipid peroxidation and the increase in SOD and CAT or the stimulation of GR. It is noteworthy that GR leads to the synthesis of reduced glutathione, which is important in the defense of the cell against toxic substances and the prevention of the occurrence of mutations [29]. 5. Conclusions MTX significantly decreases the activity of enzymatic antioxidants, reduce the MI and increase the chromosomal aberrations of all types in bone marrow. This gives further evidence on the genotoxic effects of MTX on the bone marrow. 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Introduction Methods Resuts Discussion Conclusions Acknowledgments Authors' contributions Competing interests Ethical approval References Effect of Methotrexate and Omega-3 Combination on Cytogenetic Changes of Bone Marrow and Some Enzymatic Antioxidants: An Experimental Study Inaam N. Ali1, Muthana M. Awad2, Alaa S. Mahmood2,* 1 Water and Environment Directorate, Ministry of Sciences and Technology, Baghdad, Iraq 2 Department of Biology, College of Science, University of Anbar, Anbar, Iraq * Corresponding author: A. S. Mahmood (alaashm91@gmail.com) Abstract: Objective: To assess the effect of methotrexate and omega-3 combination on cytogenetic changes of bone marrow and activities of some enzymatic antioxidants. Methods: Fifty-six mature male Wistar rats were divided into two experimental groups and a control group. The first experimental group was sub-divided into three sub-groups depending on the concentration of methotrexate (MTX): X1 (0.05 mg/kg MTX), X2 (0.125 mg/kg MTX) and X3 (0.250 mg/kg MTX), which were given intraperitoneally on a weekly basis for eight weeks. The second experimental group (MTX and omega-3 group) was also sub-divided into three sub-groups (Y1, Y2 and Y3), which were injected intraperitoneally with 0.05, 0.125 and 0.25 mg/kg MTX, respectively, weekly for eight weeks accompanied by the oral administration of 300 mg/kg omega-3. The rats of the control group were given distilled water. The enzymatic activity of catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR) were measured in the sera of rats. In addition, the mitotic index (MI) and chromosomal aberrations of bone marrow were also studied. Results: MTX resulted in a significant decrease in the activities of CAT, SOD and GR compared to the controls. It also increased the MI and chromosomal aberrations of rat bone marrows. On the other hand, omega-3 significantly increased the activities of the investigated enzymatic antioxidants and reduced the MI and chromosomal aberrations in treated mice when given in combination with MTX. Conclusions: MTX has a genotoxic effect on the bone marrow by increasing the MI and all types of chromosomal aberrations and decreasing the enzymatic activity of CAT, SOD and GR. The addition of omega-3 can lead to a protective effect by reducing the toxic and mutagenic effects of MTX. Keywords: Methotrexate, Omega-3, Antioxidant, Wistar rat, Chromosomal aberration, Mitotic index 1. Introduction Methotrexate (MTX) is a folic acid antagonist because of their chemical similarity [1]. Vezmar et al. [2] showed that MTX affects the synthesis of nucleic acids deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) by interfering with the biosynthesis of thymine and purines. It also directly affects the rapidly dividing and intact cells, especially those in the mucous membranes of the mouth, intestine and bone marrow [3]. Omega-3 is a type of unsaturated fats, which are classified as essential fatty acids that cannot be manufactured by the body and should be taken with food [4]. Sources of omega-3 include fish oils, such as salmon, sardines and tuna, as well as soybeans, walnuts, raisins and linseed, almonds and olive oils [5]. Omega-3 is used in the prevention of a number of diseases such as rheumatoid arthritis, ulcerative colitis, asthma, atherosclerosis, cancer, and cardiovascular diseases [6]. A large amount of evidence indicates that omega-3 fatty acids have significant health benefits, including anti-inflammatory and antioxidant properties besides their effect on blood cholesterol levels [7]. Antioxidants retard the oxidation process by different mechanisms such as the removal of free radicals [8]. Enzymatic antioxidants include catalase (CAT), which is the first line of defense in the cell that removes hydrogen peroxide formed during biological processes by converting it into an aldehyde, and superoxide dismutase (SOD). There are three major families of SOD enzymes: manganese SOD (Mn-SOD) in the mitochondria and peroxisomes, iron SOD (Fe-SOD) in prokaryote cells and copper/zinc SOD (Cu-Zn SOD) in the cytoplasm of eukaryote cells [9]. Therefore, changes in the metal co-factors (manganese, iron, copper and zinc) can alter the effectiveness of SOD and may lead to diseases as a result of oxidative stress [10]. Glutathione reductase (GR) is also an enzymatic antioxidant that converts the oxidized glutathione to the reduced glutathione in the presence of NADPH, which is oxidized to NADP [11]. Therefore, the aim of the present study was to assess the effects of MTX and omega-3 on the cytogenetic changes of bone marrow as well as the activities of CAT, SOD and GR enzymatic antioxidants in male rats. 2. Method 2.1. Laboratory animals and experimental design Fifty-six mature male Wistar rats (Rattus norvegicus), aged 10–12 weeks old and weighing 250–300 gm, were used in the present study. The rats were kept in separate cages, with natural 13- hour light and 11-hour dark periods in a contamination-free environment with a controlled temperature (28.0 ± 1.0°C). In addition, rats were maintained on a standard diet and tap water ad libitum. The rats were randomly allocated to two experimental groups and a control group. The first experimental group (MTX group) included 24 rats injected intraperitoneally with different MTX dilutions with distilled water [12]. It was sub-divided into three sub-groups (eight rats per sub-group) according to MTX concentration as follows: X1 (0.05 mg/kg MTX), X2 (0.125mg/kg MTX) and X3 (0.25 mg/kg MTX). All rats were given a single dose of the specified MTX concentration weekly for eight weeks. The second experimental group (MTX and omega-3 group) included 24 rats allocated to three sub-groups (Y1, Y2 and Y3), which were injected intraperitoneally with 0.05, 0.125 and 0.25 mg/kg MTX, respectively, weekly for eight weeks accompanied by the oral administration of 300 mg/kg omega-3. The control group included eight rats that were intraperitoneally injected with distilled water and given a single dose of distilled water orally weekly for eight weeks. 2.2. Blood collection and processing After the end of the dosing period, 5 ml of blood were withdrawn from the heart (by cardiac puncture) using a 5 cc disposable syringe. The collected blood was immediately poured into a clean sterile screw-capped tube (plain tube) and left for coagulation in a water bath at 37°C for 15 minutes. After coagulation of blood, the plain tube was centrifuged for 5 minutes at 1500 rpm. Then the samples were stored at -20°C for subsequent analysis. 2.3. Measurement of the activity of antioxidant enzymes The antioxidant activities of CAT, SOD and GR were measured using enzyme-linked immunosorbent assay kits purchased from Kamiya Biomedical Company (Seattle, WA, US), according to the manufacturer's instructions. 2.4. Cytogenetic study of bone marrow Rats were killed by cervical dislocation, and their hip bones were cleaned from surrounding muscles and then dissected by cutting both ends of the bone. Five milliliters of physiological buffered saline were injected inside the bone to withdraw bone marrow into a test tube. Tubes were centrifuged at 2000 rpm/10 minutes. The supernatant was then removed, and 10 ml of KCL solution (0.075 M) were added to the sediment. The mixture was then incubated at 37 °C in a water bath for 30 minutes, with shaking from time to time. The tubes were then centrifuged at 2000rpm/10 minutes to remove the supernatant. However, 5 ml of a freshly prepared fixative solution (methanol: glacial acetic acid 1:3) were added gradually in the form of droplets into the inner wall of the tube with constant mixing. After that, the tubes were placed at 4 °C for half an hour to fix the cells. This process was repeated for three times, and the cells were then suspended in 2 ml of the fixative solution. The tubes were centrifuged at 2000 rpm for 5 minutes, and the supernatant was then removed while the cells were re-suspended in 1-2 ml of cold fixative solution. After shaking the tubes, 4–5 drops were then taken from each tube onto a clean slide from a height of about three feet to provide an opportunity for the cells and nuclei to spread well. The slides were stained with acridine orange solution (0.01%) for 4–5 minutes, incubated in Sorensen’s buffer (0.06M, pH 6.5) for a minute. and then examined using a fluorescence microscope Olympus BX 51 America at a wavelength of 450–500 nm [13, 14]. A total of 1000 cells were examined, and both dividing and non-dividing cells were calculated [13]. Mitotic index (MI) was calculated according to the following formula [13]: MI= No. of dividing cells / 1000 × 100 2.5. Analysis of chromosomal aberrations of bone marrow cells A total of 1000 dividing cells were examined on the stained slides under a fluorescence microscope at a wavelength of 45–500 nm. The examined cells were at the first metaphase of the mitotic division, where chromosomal aberrations are clear and can be easily seen [13]. 2.6. Statistical analysis Data were analyzed using the Statistical Analysis System (SAS®) software, version 9.1 (Cary, NC, USA) [15]. Effects were expressed as mean ± standard error (SE) and statistically compared using a completely randomized design analysis of variance and least significant differences. Differences at P values <5 were considered statistically significant. 3. Results 3.1. Effects of MTX and MTX-omega-3 combination on antioxidant enzymatic activities Table (1) shows significantly lower SOD activities among rats treated with MTX or MTX-omega-3 compared to controls. Moreover, sera of rats receiving relatively high doses of MTX (sub-groups X2 and X3) showed the lowest enzymatic activities of 4.29 ± 0.01 IU and 3.93 ± 0.11 IU, respectively. On the other hand, CAT activity differed significantly between treated and control rats as well as among treated rats themselves, In this respect, the controls showed the highest activity of 39.38 ±0.02 IU, while those receiving the highest MTX concentration, either alone or in combination with omega-3 (sub-groups X3 and Y3), showed the lowest activities of 30.97 ± 0.03 IU and 32.12± 0.06 IU, respectively. Regarding GR activity, control rats showed a higher activity of 53.09± 0.05 IU compared to treated ones; however, the differences in GR activities in rats given low doses of MTX, either alone or in combination with omega-3 (sub-groups X1 and Y1), were not statistically significant. On the other hand, rats in sub-groups X3 and Y3 showed the lowest GR activities of 34.59 ± 0.63 IU and 37.15 ±0.01, respectively, with statistically significant differences from other sub-groups. 3.2. Effects of MTX and MTX-omega-3 combination on mitotic index of bone marrow cells Figure (1) shows a significant decrease in the MI in all treated groups compared to control. In addition, there was a reverse association between MTX concentration and MI, where rats treated with the highest dose of MTX (sub-group X3) showed a significant decrease in MI compared to all other treated rat sub-groups. In addition, rats in sub-groups treated with MTX and omega-3 (sub-groups Y1, Y2 and Y3) showed a significant increase in MI compared to their counterpart rats receiving MTX only. Table 1. Activity of antioxidant enzymes in rats treated with MTX and MTX-omega-3 Group Enzymatic activity (mean± SE) SOD (IU) CAT (IU) GR (µmol) Control 6.41±0.02 a 39.38±0.02 a 53.09±0.05 a X1 (0.05 mg MTX/ kg) 5.33±0.01 b 37.81±0.01 c 51.12±0.06 a Y1 (0.05 mg MTX + 300 mg omega-3/ kg) 6.08±0.04 a 38.40±0.02 b 51.97±0.03 a X2 (0.125 mg MTX/ kg) 4.29±0.01 cd 33.13±0.01 e 42.34±0.03 b Y2 (0.125 mg MTX + 300 mg omega-3/ kg) 4.99±0.40 b 36.68±0.02 d 43.02±3.04 b X3 (0.25 mg MTX/ kg) 3.93±0.11 d 30.97±0.03 g 34.59±0.63 c Y3 (0.25 mg MTX + 300 mg omega-3/ kg) 4.47±0.02 c 32.12±0.06 f 37.15±0.01 c SE, Standard error; IU, international unit; SOD, superoxide dismutase; CAT, catalase; GR, glutathione reductase; *statistically significant at P < 0.05; **statistically significant at P < 0.01. Means with different letters within the same column showed a statistically significant difference. 3.3. Effects of MTX and MTX-omega-3 combination on chromosomal aberrations of bone marrow cells Rats receiving higher concentrations of MTX (sub-group X3) showed a significant increase in all types of chromosomal aberrations, i.e., chromatid gaps, chromosome gaps, chromatid breaks, chromosome breaks, deletions and simple fragments (Figure 2 and Table 2) than those of the control group or other treated sub-groups. All rats treated with MTX-omega-3 combination showed a significant decrease in almost all types of chromosomal aberrations compared to their counterpart rats receiving MTX alone (Table 2). Figure 1. Effect of MTX and MTX-omega-3 on the MI of bone marrow cells of treated rats compared to the controls. The groups X1 (0.05 MTX), X2 (0.125 MTX) and X3 (0.250 MTX) were compared to the control group, while the groups Y1 (0.05 MTX+ omega-3), Y2 (0.125 MTX+ omega-3) and Y3 (0.25 MTX+ omega-3) were compared to X1, X2 and X3, respectively. Figure 2. Effect of MTX and MTX-omega-3 on chromosomal aberration as seen under fluorescence microscope after staining with acridine orange: (1) a simple fragment; (2) a chromatid gap; (3) a chromosomal gap (A) and a chromosomal break (B). 4. Discussion The present experiment reveals that the addition of omega-3 to MTX alleviates its effects on the activities of the antioxidant enzymes CAT, SOD and GR, and decreases the MI as well as all types of chromosomal aberrations in the bone marrow cells. Daham et al. [16] showed that the decline in antioxidants associated with chemotherapy is attributed to the increase in lipid peroxidation caused by these kinds of drugs, which increase the level of free radicals. In addition, Weijl et al. [17] showed that some chemotherapeutic drugs have a negative effect on the antioxidant levels such as GR, whose activity decreases as a result of its involvement in many cellular processes such as cell defenses against the toxicity of some compounds. Al-Dalawy et al. [18] found that the decrease in the level of SOD is an evidence of its increased activity due to the increased release of free radicals. MTX causes an increase in the release of free radicals, including the OH radical that causes direct damage to DNA [16]. Al-Helaly [19] showed that the amount of food taken has an effect on antioxidants, where nutritional deficiency decreases the antioxidant levels, thus increasing free radicals that cause damage to DNA. Table 2. Chromosomal aberrations of bone marrow cells in rats treated with MTX and MTX-omega-3 Group Type of chromosomal aberration(mean ± SE) Chromatid gap Chromosome Gap Chromatid breaks Chromosome breaks Deletion Simple Fragments Chromosomal aberration (%) Control 1.33±0.33 e 0.00±0.00 e 1.67±0.33 c 0.33±0.15 c 0.00±0.00 0.67±0.33 cd 0.04±0.005 f X1 2.75±0.47 cd 1.50±0.28 cd 2.50±0.64 bc 1.00±0.41 bc 0.50±0.28 bc 0.75±0.25 bcd 0.09±0.02 de Y1 1.75±0.47 de 0.75±0.25 de 1.50±0.28 c 1.00±0.00 bc 0.75±0.25 abc 0.75±0.25 abc 0.065±0.005 ef X2 4.67±0.33 b 2.67±0.33 ab 2.67±0.33 bc 1.67±0.33 ab 0.67±0.33 abc 1.67±0.33 ab 0.14±0.006 bc Y2 3.00±0.00 c 2.00±0.00 bc 3.00±0.057 bc 1.33±0.33 b 0.67±0.33 abc 0.33±0.15 d 0.106±0.003 cd X3 6.80±0.37 a 3.00±0.31 a 4.60±0.74 a 2.40±0.24 a 1.40±0.24 a 1.80±0.37 a 0.20±0.017 a Y3 5.60±0.40 ab 2.40±0.24 ab 3.60±0.24 ab 1.80±0.20 ab 1.20±0.20 ab 1.40±0.24 abc 0.16±0.003 b LSD 1.231** 0.814** 0.602** 0.841** 0.774* 0.941** 3.499* SE, Standard error; * statistically significant at P < 0.05; ** statistically significant at P < 0.01. Means with different letters within the same column showed a statistically significant difference. X1 (0.05 mg MTX/ kg); X2 (0.125 mg MTX/ kg); X3 (0.25 mg MTX/ kg); Y1 (0.05 mg MTX + 300 mg omega-3/ kg); Y2 (0.125 mg MTX + 300 mg omega-3/ kg); Y3 (0.25 mg MTX + 300 mg omega-3/ kg). In the present study, the intraperitoneal administration of MTX to rats also caused a decrease in the MI of bone marrow and a significant increase in the rate of abnormal chromosomal aberration compared to the control rats. This finding is consistent with those reported previously [20], [21]. The effect of MTX can be attributed to its ability to interfere with the genetic material, leading to the appearance of toxic and mutagenic consequences. Rushworth et al. [22] reported that MTX leads to a lack of dihydrofolate reductase, which is the key to the growth and cell division processes. This, in turn, leads to a reduction of the nucleotides involved in the building of DNA and, therefore, to a stop or obstruction of the repair mechanisms of the damaged DNA. In addition, Wong and Choi [23] concluded that MTX inhibits the action of enzymes controlling the purine metabolism, which leads to the accumulation of adenosine in addition to the damage of the molecule itself and to the occurrence of chromosomal aberrations. Jafer et al. [24] reported the ability of MTX to induce chromosomal aberration in humans or animals by preventing the repair of DNA and affecting the proteins found in chromosomes. These findings were also confirmed by Hussain et al. [25], who found that MTX causes an increase in chromosomal aberrations. In the present study, the MI showed a significant increase in rat sub-groups treated with MTX-omega-3 combination, but there was a decrease in the rate of chromosomal aberration, which confirms the role of omega-3 unsaturated fatty acids in protecting the cell from the impact of free radicals [26], [27]. Attia and Nasr [28] reported the antioxidant effect of omega-3, which was attributed to the reduction in lipid peroxidation and the increase in SOD and CAT or the stimulation of GR. It is noteworthy that GR leads to the synthesis of reduced glutathione, which is important in the defense of the cell against toxic substances and the prevention of the occurrence of mutations [29]. 5. Conclusions MTX significantly decreases the activity of enzymatic antioxidants, reduce the MI and increase the chromosomal aberrations of all types in bone marrow. This gives further evidence on the genotoxic effects of MTX on the bone marrow. 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Among the main factors that affect the productivity of crops is deficiency of nutrients. Boron (B) is an essential micronutrient for plants, and sunflower is one of the most sensitive plants to deficiency of the element. Its inadequate supply can impair sunflower plants’ metabolism and grain and oil yield. The objective of this study was to assess the effect of different boron doses on the production of sunflower grains and the content and quality of the oil obtained from them. The experimental design was randomized blocks in a factorial scheme with three cultivars (Helio251, BRS323, BRS324) and four B doses (0, 2.5, 5.0, 8.0 kg ha-1). Two harvests were performed, the first in the R5 reproductive stage and the second at the end of the R9 cycle. In both cases, the levels of B in the capitulum were measured. At the end of the cycle, the grain yield, crude protein and oil content in the grains and fatty acid profile were analyzed. The cultivars responded differently to the treatments with B. The boron fertilization influenced the grain yield and oil content, but was not correlated with the profile of the majority unsaturated fatty acids and crude protein in the grains. Variations were observed in the fatty acid profile between the cultivars, an important aspect that needs to be evaluated according to the purpose of the production. In soil with lower availability of B, cultivar BRS323 was most efficient in B uptake, grain yield and oil content and quality.

Abstract Activin A promotes fetal mouse testis development, including driving Sertoli cell proliferation and cord morphogenesis, but its mechanisms of action are undefined. We performed ribonucleic acid sequencing (RNA-seq) on testicular somatic cells from fetal activin A-deficient mice (Inhba KO) and wildtype littermates at embryonic day (E) E13.5 and E15.5. Analysis of whole gonads provided validation, and cultures with a pathway inhibitor discerned acute from chronic effects of altered activin A bioactivity. Activin A deficiency predominantly affects the Sertoli cell transcriptome. New candidate targets include Minar1, Sel1l3, Vnn1, Sfrp4, Masp1, Nell1, Tthy1 and Prss12. Importantly, the testosterone (T) biosynthetic enzymes present in fetal Sertoli cells, Hsd17b1 and Hsd17b3, were identified as activin-responsive. Activin-deficient testes contained elevated androstenedione (A4), displayed an Inhba gene dose-dependent A4/T ratio, and contained 11-keto androgens. The remarkable accumulation of lipid droplets in both Sertoli and germ cells at E15.5 indicated impaired lipid metabolism in the absence of activin A. This demonstrated for the first time that activin A acts on Sertoli cells to determine local steroid production during fetal testis development. These outcomes reveal how compounds that perturb fetal steroidogenesis can function through cell-specific mechanisms and can indicate how altered activin levels in utero may impact testis development.