Littérature scientifique sur le sujet « Markers turnover osseo »

556 Background: Ovarian failure secondary to adjuvant chemotherapy is known to have an adverse effect on bone mineral density and to increase bone turnover markers. The effects of chemotherapy with growth factor support in the absence of hormonal changes have not been described. The impact of zoledronic acid on these changes was also explored. Methods: We evaluated bone turnover markers in 82 women undergoing neoadjuvant chemotherapy for localized stage II/III breast cancer at initial diagnosis prior to treatment and after 4 cycles of epirubicin (75mg/m2)-docetaxel (75mg/m2) with pegylated G-CSF support with or without zoledronic acid. 47% of patients were post-menopausal and all groups were balanced for other variables. Women were randomized to receive zoledronic acid 4 mg IV every 3 weeks concurrently with chemotherapy (n=41) versus no bisphosphonate treatment (n=41). Bone turnover markers included: urinary N-telopeptide (NTx), serum bone specific alkaline phosphatase (BAP)and osteocalcin (OSTEO). Results: Women, regardless of menopausal status, who received no bisphosphonate had statistically significant increases in NTx, from baseline after 3 months of neoadjuvant chemotherapy using multivariable mixed repeated measures (p=0.0213). Women who received zoledronic acid concurrently with neoadjuvant chemotherapy had statistically significant decreases in NTx (p<0.0001), BAP (p<0.0001) and OSTEO (p=0.0295) from baseline. This is the first demonstration that anthracycline-taxane chemotherapy with growth factor support increased bone turnover markers in both post-menopausal and pre-menopausal women independent of hormone therapy, radiation therapy and surgery. Conclusions: Neoadjuvant chemotherapy with anthracycline- taxane and growth factor support increased bone resorption markers in both post-menopausal and pre-menopausal women. Zoledronic acid given concurrently with each cycle of chemotherapy reversed this increase in bone turnover markers. No significant financial relationships to disclose.

Osteoporosis in chronic kidney disease (CKD) is also referred to as ‘CKD with low bone mineral density (BMD)’, because the cause of low BMD in CKD includes chronic kidney disease-mineral bone disorders (CKD-MBD) such as secondary hyperparathyroidism, osteomalacia, and adynamic bone disease. Diagnostic methods of osteoporosis in CKD include FRAX®, BMD, and bone turnover markers as well as CKD-MBD biochemical parameters- calcium, P, alkaline phosphatase, PTH, and 25(OH)D3. The management of osteoporosis in CKD prioritizes CKD-MBD management over selection of bone anti-resorptive agents or osteo-anabolic agents according to clinical and laboratory findings.

Serum osteocalcin is a sensitive marker of suppressive effects of exogenous glucocorticoids on bone turnover. It has been suggested, however, that the degree of suppression detected by different assays may vary. Whether discrepancies between various assays influence conclusions from group studies of exogenous glucocorticoids has not been evaluated. The aim of the present study was to compare the CAP fluoroimmunoassay (FEIA), OSTK-PR and ELSA-OSTEO assays for assessment of prednisolone-induced effects on serum osteocalcin. Twelve men and eight premenopausal women aged 19-45 (mean 31) years were studied. All subjects were healthy. The design was a randomised double-blind, placebo-controlled parallel- group study with 2 days run-in, 3 days treatment and 4 days run-out. During run-in and run-out no medication was given. During the treatment period the subjects took either 20 mg prednisolone twice daily or placebo. Blood was collected on the last day of each period. Intra- and intergroup comparisons showed prednisolone treatment to be associated with a statistically significant suppression of osteocalcin which was detected by all assays (ANOVA;P<0.0001). In the individual subjects the response to prednisolone was the same for each assay. The CAP FEIA, OSTK-PR and ELSA-OSTEO assays seem equally sensitive for evaluation of osteocalcin in group studies of oral glucocorticoids.

Elevated serum levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) in patients with acromegaly result in intensified bone turnover, as evidenced by increased levels of bone remodeling markers and higher risk of low-traumatic vertebral fractures. However, it was repeatedly observed that bone mineral density (BMD) is normal or even increased in patients with acromegaly (including the active stage of the disease). Increased secretion of GH/IGF-1 causes structural changes in the vertebrae and peripheral joints (osteophyte formation and cartilage hypertrophy), resulting in pain and various deformities of the articular system. These changes are known under the common name «acromegalic arthropathy». It is quite specific complication of the disease. Skeletal complications of acromegaly can persist even after radical treatment, i.e., their course and progression, presumably, do not necessarily depend on the remission level of the underlying disease. This review summarizes the current understanding of the pathophysiology, clinical presentation, diagnosis, and treatment of osteo-articular complications of acromegaly.

Background: Fracture of long bones is a common orthopaedic condition noticed in dogs and its primary goal is to completely restore the function of the injured limb as early as possible. Osteo-conductivity of hydroxyapatite can be improved further by decreasing the particle size to nanometre range and incorporation of inorganic materials in hydroxyapatite can enhance osteoblast cell material interactions. Strontium, Zinc, Silver and Fluorine are known to play an important role in the bone formation and also affect bone material characteristics such as crystallinity, degradation behaviour and mechanical properties. When doped with plasma spray nanohydroxyapatite, these multi-ions cause no harm to the physical environment during the degradation process of hydroxyapatite as these are nontoxic and play significant role in bone metabolism, growth and nourishment. Bone markers have tremendous potential as a rapid and sensitive method for assessing the response of the skeleton to medical or surgical interventions providing valuable information regarding bone turn over in animals. Hence, the current study was undertaken to evaluate the potential of multi-ion doped nano-hydroxyapatite coated intramedullary titanium implants in long bone fracture repair in dogs compared to the conventional intramedullary titanium implants through radiographical studies and evaluation of bone markers. Methods: Radiographical evaluation, Sandwich ELISA kits developed by Bioassay technology laboratory. Result: Plasma spray nano-hydroxyapatite coated titanium intramedullary implants have shown excellent osteo-conductivity when doped with multi-ions of Strontium, Zinc, Silver and Fluorine facilitating rapid osteoblastic activity and rapid bone turnover at the fracture site and complete fracture healing by 3rd week post-operatively as evidenced by radiographic scores and a peak BALP (Canine Bone Alkaline Phosphatase) values and early limb usage. Bone reabsorption and bone tissue remodelling due to osteoclastic action at the fracture site was quicker when the multi-ion doped nano-hydroxyapatite coated titanium intramedullary implants were used which is evidenced by the radiographic scores and highest CTX (Canine C-telopeptide of Type 1 Collagen) values indicating completion of fracture healing and near completion of bone tissue remodelling by 9th post-operative week in long bone fracture repair in dogs.