Academic literature on the topic 'Cushing's'

Exophthalmos is typically associated with Graves' ophthalmopathy. Although originally described by Harvey Cushing, exophthalmos is an underappreciated sign of Cushing's syndrome. We present a case of a 38-year-old female who presented with severe bilateral proptosis and was subsequently diagnosed with Cushings disease. We discuss the possible mechanisms causing exophthalmos in patients with either endogenous or exogenous hypercortisolemia.

From the very beginning of his career, Harvey Williams Cushing (1869–1939) harbored a deep interest in a complex group of neoplasms that usually developed at the infundibulum. These were initially known as “interpeduncular” or “suprasellar” cysts. Cushing introduced the term “craniopharyngioma” for these lesions, which he believed represented one of the most baffling problems faced by neurosurgeons. The patient who most influenced Cushing's thinking was a 16-year-old seamstress named “Mary D.,” whom he attended in December 1901, exactly the same month that Alfred Fröhlich published his seminal article describing an adiposogenital syndrome in a young boy with a pituitary cyst. Both Cushing's and Fröhlich's patients showed similar symptoms caused by the same type of tumor. Notably, Cushing and Fröhlich had met one another and became good friends in Liverpool the summer before these events took place. Their fortunate relationship led Cushing to realize that Fröhlich's syndrome represented a state of hypopituitarism and provided a useful method of diagnosing interpeduncular cysts. It is noteworthy that Cushing's very first neurosurgical procedure on a pituitary tumor was performed in the case of Mary D.'s “interpeduncular cyst,” on February 21, 1902. Cushing failed to remove this lesion, which was later found during the patient's autopsy. This case was documented as Pituitary Case Number 3 in Cushing's masterpiece, The Pituitary Body and Its Disorders, published in 1912. This tumor was considered “a teratoma”; however, multiple sources of evidence suggest that this lesion actually corresponded to an adamantinomatous craniopharyngioma. Unfortunately, the pathological specimens of this lesion were misplaced, and this prompted Cushing's decision to retain all specimens and documents of the cases he would operate on throughout his career. Accordingly, Mary D.'s case crystallized the genesis of the Cushing Brain Tumor Registry, one of Cushing's major legacies to neurosurgery. In this paper the authors analyze the case of Mary D. and the great influence it had on Cushing's conceptions of the pituitary gland and its afflictions, and on the history of pituitary surgery.

By the time Harvey Cushing entered medical school, nerve reconstruction techniques had been developed, but peripheral nerve surgery was still in its infancy. As an assistant surgical resident influenced by Dr. William Halsted, Cushing wrote a series of reports on the use of cocaine for nerve blocks. Following his residency training and a hiatus to further his clinical interests and intellectual curiosity, he traveled to Europe and met with a variety of surgeons, physiologists, and scientists, who likely laid the groundwork for Cushing's increased interest in peripheral nerve surgery. Returning to The Johns Hopkins Hospital in 1901, he began documenting these surgeries. Patient records preserved at Yale's Cushing Brain Tumor Registry describe Cushing's repair of ulnar and radial nerves, as well as his exploration of the brachial plexus for nerve repair or reconstruction. The authors reviewed Harvey Cushing's cases and provide 3 case illustrations not previously reported by Cushing involving neurolysis, nerve repair, and neurotization. Additionally, Cushing's experience with facial nerve neurotization is reviewed. The history, physical examination, and operative notes shed light on Cushing's diagnosis, strategy, technique, and hence, his surgery on peripheral nerve injury. These contributions complement others he made to surgery of the peripheral nervous system dealing with nerve pain, entrapment, and tumor.

Although recent efforts to advance the treatment of gliomas through radiotherapy and chemotherapy may seem to be a relatively new area of growth and development, these efforts have been in progress since the therapeutic potential of radiation therapy was discovered in the late 19th century. Cushing's use of brachytherapy has been mentioned several times in the literature without receiving an appropriate in-depth analysis. The reasoning behind Cushing's initial use of brachytherapy was not fully examined, and a close analysis of the outcomes of this therapy was not made. In addition, Cushing's use of his “radium bomb” occurred more commonly than the 3 cases previously documented. The authors reviewed all the patient records available at the Cushing Brain Tumor Registry—which represents the most complete series of patient records from the Cushing era—and selected those patients who underwent treatment with Cushing's “radium bomb.” The authors place these early attempts to optimize interstitial radiation of brain tumors in their historical perspective.

Of Harvey Cushing's many contributions to neurosurgery, one of the least documented is his early surgical intervention in children and his pioneering efforts to establish pediatric neurosurgery as a subspecialty. Between 1896 and 1912 Cushing conducted nearly 200 operations in children at The Johns Hopkins Hospital. A review of his records suggests that the advances he made in neurosurgery were significantly influenced by his experience with children. In this historical article, the authors describe Cushing's treatment of 6 children, in all of whom Cushing established a diagnosis of “birth hemorrhage.” By reviewing Cushing's operative indications, techniques, and outcomes, the authors aim to understand the philosophy of his pediatric neurosurgical management and how this informed his development of neurosurgery as a new specialty.

This historical review explores Harvey Cushing's difficulties with both the British and American armies during his World War I service to definitively examine the rumor of his possible court martial. It also provides a further understanding of Cushing the man. While in France during World War I, Cushing was initially assigned to British hospital units. This service began in May 1917 and ended abruptly in May 1918 when the British cashiered him for repeated censorship violations. Returning to American command, he feared court martial. The army file on this matter (retrieved from the United States National Archives) indicates that US Army authorities recommended that Cushing be reprimanded and returned to the US for his violations. The army carried out neither recommendation, and no evidence exists that a court martial was considered. Cushing's army career and possible future academic life were protected by the actions of his surgical peers and Merritte Ireland, Chief Surgeon of the US Army in France. After this censorship episode, Cushing was made a neurosurgical consultant but was also sternly warned that further rule violations would not be tolerated by the US Army. Thereafter, despite the onset of a severe peripheral neuropathy, probably Guillian Barré's syndrome, Cushing was indefatigable in ministering to neurosurgical needs in the US sector in France. Cushing's repeated defying of censorship regulations reveals poor judgment plus an initial inability to be a “team player.” The explanations he offered for his censorship violations showed an ability to bend the truth. Cushing's war journal is unclear as to exactly what transpired between him and the British and US armies. It also shows no recognition of the help he received from others who were instrumental in preventing his ignominious removal from service in France. Had that happened, his academic future and ability to train future neurosurgical leaders may have been seriously threatened. Cushing's foibles notwithstanding, all realized that he contributed greatly to both British and US war neurosurgery. United States Army surgeons who operated upon brain wounds in France recognized Cushing as their leader.

Influenced by individuals such as his parents, Osler, and Halsted, and by his early medical student experience, Harvey Cushing developed a strong interest in collecting, especially antiquarian medical books. Even today, his collection housed at Yale University is one of the most prestigious in the world. Cushing's interest in archives is further manifested and reinforced by his establishment of the Cushing Brain Tumor Registry. The following is a review of Cushing's background not as an eminent clinician and surgeon but as an individual best described as a bibliophile, archivist, and ardent collector of medical paraphernalia.

✓ In contemporary American culture, the term “brain surgeon” conjures up the image of an intensely singleminded professional, who deals with terribly complex matters of life and death. These descriptors find their personification in Harvey Cushing, because they are derived directly from him. This hypothesis was tested by a complete search of the New York Times Index and the Reader's Guide to Periodical Literature for the years 1919 to 1942. All entries for Harvey Cushing were reviewed in the original sources. In the New York Times, Cushing's first significant exposure was in response to his winning a Pulitzer Prize in 1925. Major editorial coverage began in 1934, and was especially prominent with the publication of From a Surgeon's Journal in 1936. The process of lionizing Cushing by creating an overdrawn caricature reached its apotheosis in Time magazine in 1939. The Time article was actually a report of Cushing's 70th birthday party. It expounded all of the descriptors that are now associated with “brain surgeon.” Thus, it was Cushing's literary skills that initially brought him recognition from editors who were arbiters of public opinion. This attention seems to have been the conduit to his mythologization by the larger public. Although unnamed, it is really Cushing's image that still persists as the prototypical “brain surgeon” in the collective American consciousness.

Hypothesis: That siRNAs could be translated into systemic therapy for Cushing's disease in man. Background and importance: Cushing's disease is an uncommon but devastating condition, with a mean age of onset of 36 years, and a five-fold excess mortality when inadequately treated. Major complications include diabetes, hypertension, osteoporosis, life-threatening infection, depression and psychosis. No established ACTH-Iowering medical therapy exists. 95% of cases are caused by a tiny benign corticotrope adenomas of the pituitary gland, often only millimetres in diameter, and in 40% of cases are invisible on MR!. These adenomas express the prohormone 'Pro-opiomelanocortin' (pOMC), which undergoes post-translational processing to adrenocorticotrophin (ACTH), before secretion into the systemic circulation. ACTH drives the adrenal glands to synthesise and secrete excessive amounts of the hormone cortisol, which causes the clinical condition of Cushing's disease. Invasive neurosurgery aimed at removal of the pituitary tumour, causes long-term remission in only 50% of patients with Cushing's disease and results in hypopituitarism in approximately half. Hypopituitarism is associated with a two-fold excess mortality. Bilateral adrenalectomy is effective treatment but is complicated by life-long hypoadrenalism (two-fold excess mortality) and the development of an expanding, and pituitary mass (Nelson's syndrome) in up to 30% of cases. Use of adrenal steroidogenesis inhibitors is not usually effective in long-term management.

Patients with Cushing’s syndrome often complain about sleep disruption and excessive day time sleepiness, which could contribute to worsening quality of life and metabolic comorbidities (obesity, hypertension, diabetes mellitus, dyslipidaemia) associated with hypercortisolism. Sleep disorders have been shown to increase the risk of developing cardiovascular disease and that the risk of cardiovascular disease in patients with hypercortisolism may be worsened by impaired sleep. Cushing’s syndrome patients may also be at increased risk for obstructive sleep apnea due to their obesity.
Dissertation (MSc)--University of Pretoria, 2020.
Physiology
MSc
Restricted

El Síndrome de Cushing (SC) es una enfermedad endocrina rara, causada por una larga exposición a la hormona cortisol. Este hipercortisolismo endógeno determina síntomas endocrinos, cognitivos y psiquiátricos. Algunos estudios de neurorradiología han investigado la estructura cerebral en pacientes con SC encontrando alteraciones. Los objetivos de los estudios de esta tesis se centran en investigar la microestructura de la Sustancia Blanca cerebral (SB), un área que hasta ahora apenas ha sido estudiada en el SC, en evaluar los síntomas neuropsiquiátricos (depresión y ansiedad) y neuropsicológicos (velocidad de procesamiento de la información) y su relación con la SB. La Imagen con Tensor de Difusión (DTI) es una técnica de resonancia magnética (RM) que permite el estudio no-invasivo in vivo del cerebro evaluando el movimiento de las moléculas de agua a través de los axones. Existen diferentes mapas de DTI que permiten estudiar la arquitectura de la SB y mostrar anomalías microestructurales de la SB. La anisotropía fraccional (FA) refleja la integridad de la SB, mientras que los incrementos en la difusividad media (MD) pueden ser debidos ​​a desmielinización y/o edema. La disminución de la difusividad axial (AD) indica la pérdida axonal, mientras que el aumento de la difusividad radial (RD) se relaciona más con la desmielinización. En este trabajo se incluyeron 35 pacientes con SC y 35 voluntarios control sanos. En un primer estudio, se realizó un análisis de DTI comparando a los pacientes con SC con los controles sanos, seguido de un segundo análisis en el cual los pacientes fueron separados en SC activo, SC controlado y SC curado. Los resultados revelaron reducciones generalizadas de la FA, aumentos de MD y RD y un aumento parcial de la AD en pacientes con SC en comparación con los controles sanos. El análisis de subgrupos demostró este mismo patrón en la SB en pacientes con SC activo, controlado y curado, lo que sugiere un inicio temprano y duradero de las alteraciones en la microestructura de la SB. Las alteraciones de la SB fueron independientes del hipercortisolismo concomitante y de la presencia o ausencia de otros factores de riesgo cardiovascular incluidos en el análisis, como fueron la hipertensión, dislipidemia y la obesidad. Nuestro objetivo en un segundo estudio fue el investigar los trastornos del estado de ánimo y neuropsicológicos en los pacientes con SC y su relación con las alteraciones que habíamos visto en la SB. Planteamos la hipótesis de que los trastornos del estado de ánimo, utilizando el Beck Depression Inventory II (BDI-II) y el State-Trait Anxiety Inventory (STAI), serían mayores en los pacientes con SC que en los controles, y que se relacionarían con las alteraciones de la SB. Además, hipotetizamos que los pacientes con SC podrían mostrar anomalías en la velocidad de procesamiento de información, utilizando el Symbol Digit Modalities Test (SDMT), posiblemente vinculadas a las alteraciones de la SB, lo que sería debido a la conectividad funcional. Los resultados mostraron mayores trastornos del estado de ánimo (síntomas de depresión y de ansiedad), sin diferencias en las puntuaciones de velocidad de procesamiento de la información, en los pacientes con SC comparados con los controles sanos. En el estudio caso-control con DTI, los síntomas depresivos se correlacionaron negativa y positivamente, respectivamente con FA y RD, lo que refleja un patrón de alteraciones funcionales en estos pacientes que está vinculado a la pérdida de mielina y de la integridad axonal. FA y AD se correlacionaron positivamente con la velocidad de procesamiento de la información. Esto parece implicar que el estado/integridad de la SB determina una mejor ejecución en el procesamiento de la información tanto en pacientes con SC como en controles.
Cushing’s syndrome (CS) is an endocrine disorder due to prolonged exposure to cortisol. This endogenous hypercortisolism determines endocrine, cognitive and psychiatric symptoms. A few imaging studies have investigated brain structures in patients with CS and have observed brain damage. The aims of the studies described in this thesis were to explore the microstructure of cerebral white matter (WM), a topic hardly investigated up to now in CS, and to evaluate neuropsychiatric symptoms (depression and anxiety) and cognitive impairment (information processing speed) and their relationship with the WM. Diffusion Tensor Imaging (DTI) is a Magnetic Resonance (MR) imaging technique that allows noninvasive, in vivo study of the brain by assessing the motion of water molecules along and across neural axons. Different DTI maps show WM architecture and can depict microstructural WM abnormalities. Fractional anisotropy (FA) reflects WM integrity, while increases in mean diffusivity (MD) may be caused by demyelination or edema. Decreases in axial diffusivity (AD) indicate axonal loss, while increased radial diffusivity (RD) is related to demyelination. Thirty-five patients with CS and 35 healthy control volunteers were included in these studies. In the first study, a DTI analysis was performed comparing patients with CS with healthy controls, followed by a second analysis in which patients were separated into active CS, remitted CS, and cured CS. Results revealed widespread reductions in whole brain FA, increases in MD and RD and partially also of AD in patients with CS compared to healthy controls. The subgroup analysis demonstrated this same pattern of WM damage in patients with active, remitted and cured CS, suggesting an early onset and persistent damage of brain WM microstructure. DTI alterations seemed to be independent of concomitant hypercortisolism and the presence or absence of other cardiovascular risk factors included into the analysis like hypertension, dyslipidemia, and obesity. Our aim in the second study was to investigate mood disturbances and cognitive impairment in CS patients, and their relationship to WM alterations on DTI. We hypothesized that mood disturbances, evaluated using the Beck Depression Inventory II (BDI-II) and State-Trait Anxiety Inventory (STAI), would be greater in CS patients than in controls, and related to widespread WM alterations on DTI. We additionally hypothesized that CS patients would show abnormalities in information processing speed, evaluated using the Symbol Digit Modalities Test (SDMT), possibly related to WM alterations, since WM state has been related to connectivity function. Results showed greater mood disturbances (depression and anxiety symptoms), but no differences in information processing speed scores, in CS patients compared to healthy controls. In the case-control DTI study, depressive symptoms correlated negatively with FA and positively with RD, a pattern which is linked to loss of myelin and axonal integrity. FA and AD correlated positively with information processing speed. These results indicate that WM integrity are associated with better information processing in CS patients and controls.

Cyclic-AMP dependent protein kinase (PKA) is a key intracellular signal transduction kinase that is modulated by Gs- and Gi-coupled GPCRs. Under normal physiological conditions, PKA exists as an inactive holoenzyme made up of two catalytic subunits and two regulatory subunits. Upon cAMP binding to the regulatory subunits, the catalytic subunits (PKACa) are released to perform various downstream phosphorylation events. However, aberrant PKA activation can cause various diseases including Cushing’s Syndrome, which is an endocrine disorder caused by the overproduction of cortisol by the hypothalamus-pituitary-adrenal hormone system. This disorder can be caused by pituitary adenomas that release unregulated amounts of ACTH, adrenal adenomas that release unregulated amounts of cortisol without ACTH stimulation, and ectopic tumors outside the hypothalamus-pituitary-adrenal axis that produce ACTH. In recent genomic studies of patients with ACTH-independent Cushing’s Syndrome, the L205R-PKACamutant has been discovered. Through various studies on the mutant enzyme multiple research groups learned that the single point mutation causes a loss in sensitivity to cAMP signaling, a loss in binding to PKA regulatory subunits, and unregulated phosphorylation of PKACasubstrates, which ultimately leads to the increased cortisol biosynthesis in these patients. The first part of this work describes the enzymology and inhibition studies of known inhibitors against both wt- and L205R-PKACa. Early in the enzymology studies we developed at medium throughput endpoint assay that used Rhodamine-kemptide as the substrate and as a chromophore separating substrate and phosphorylated product using a reverse-phase HPLC method. The analysis of the substrate peptide against both wild-type and mutant enzyme showed a 6-fold decrease in the KMand a 2-fold decrease in kcat, and a similar but lower order of magnitude effect was observed for the studies with ATP. The inhibition studies were performed using the substrate competitive inhibitor PKI(5-24), which showed a 253-fold higher potency towards the wild-type enzyme over the mutant while the ATP-competitive inhibitor was determined to be equipotent. Using this information we used modeling studies to aid in the development of mutant selective functional inhibitors for the substrate-binding pocket. Additionally, we begun to explore the use of Proteolysis Targeting Chimeras, or PROTACs, as another means for targeting the L205R mutant enzyme.

As propriedades anti-inflamatórias e imunossupressoras dos glicocorticoides (GC) justificam o uso destes esteroides em diversas condições clínicas, apesar dos seus importantes efeitos adversos. A osteoporose induzida por glicocorticoide (OIG) é considerada a causa mais importante de osteoporose secundária. Trata-se de uma doença multifatorial que envolve alterações sistêmicas, teciduais e da sinalização das células ósseas. Além disso, o hipercortisolismo também se associa à obesidade, redistribuição de gordura, resistência insulínica e diabetes mellitus. Curiosamente, nestes distúrbios metabólicos em que a massa óssea está preservada, há maior fragilidade óssea. Nos últimos anos, diversas evidências mostram complexa interação entre o metabolismo mineral e o energético, em particular entre o tecido adiposo e ósseo. Neste cenário, a doença de Cushing (DC) é um modelo clínico conveniente para avaliar diversos mecanismos envolvidos no complexo processo de desenvolvimento de osteoporose. O objetivo deste trabalho foi avaliar, em um estudo basal e em um estudo prospectivo, diversos aspectos da interação entre o metabolismo mineral e energético em mulheres com DC e o seu possível impacto sobre a massa óssea, bem como a associação entre a massa óssea e os diversos tipos de tecido adiposo. No estudo basal, avaliamos três grupos de indivíduos, pareados por sexo e idade: grupo controle (C; n=27), grupo obeso (O; n=16) e grupo doença de Cushing (DC; n=16). No estudo prospectivo, avaliamos o grupo DC em três momentos: pré-operatório (Pré-op; n=11), 6º mês pós-operatório (6º mês PO; n=10) e 12º mês pósoperatório (12º mês PO; n= 10). No estudo basal, os grupos O e DC diferiram em relação ao C quanto ao peso e IMC (p<0,05). O grupo DC apresentou valores significativamente maiores de glicemia, insulinemia, hemoglobina glicosilada (HbA1c), HOMA-IR e leptina em relação aos grupos C e O (p<0,05). Adicionalmente, o grupo DC mostrou níveis baixos de osteocalcina em relação aos grupos C e O (p<0,05) e também de PTH, 25-OH vitamina D (25(OH)D) e adiponectina em relação ao grupo C (p<0,05). Não houve diferença entre os grupos em relação às dosagens de IGF-I e preadipocyte factor 1 (Pref-1). O grupo DC apresentou menor massa óssea em coluna lombar em relação aos grupos C e O (p<0,05) e menor massa óssea em corpo total quando comparado ao grupo O (p<0,05). O Trabecular bone score (TBS) foi capaz de evidenciar prejuízo na qualidade óssea nos grupos O e DC, mostrando comprometimento maior no grupo DC (p<0,05). A adiposidade de medula óssea (AMO) de L3 foi significativamente maior no grupo DC em relação aos grupos C e O (p<0,05). O grupo DC apresentou maior teor de tecido adiposo subcutâneo (SAT), visceral (VAT), relação VAT/SAT e de lipídeos intra-hepáticos (IHL) em relação ao grupo C (p<0,05). Adicionalmente, o grupo DC apresentou maior teor de VAT em relação ao grupo O (p<0,05). A osteocalcina se correlacionou de maneira positiva com TBS (r=0,5, p<0,0001) e negativa com HOMA-IR (r=-0,4, p<0,01) e AMO de L3 (r=-0,4, p<0,01). O TBS apresentou correlação negativa com HOMA-IR (r=-0,6, p<0,0001) e AMO de L3 (r=-0,5, p<0,001). A AMO de L3 se correlacionou positivamente com IMC (r=0,4, p<0,01), HOMA-IR (r=0,3, p<0,05), leptina (r=0,3, p<0,05), relação VAT/SAT (r=0,6, p<0,0001) e IHL (r=0,5, p<0,05). No estudo prospectivo, houve redução do peso e IMC e dos níveis de glicemia, insulinemia, HOMA-IR, hemoglobina glicada e leptina (p<0,05). Adicionalmente, houve aumento dos níveis de 25(OH)D, osteocalcina e deoxipiridinolina (p<0,05). Não houve diferenças significativas entre os níveis de Pref-1 e adiponectina. O TBS manteve-se estável e não houve aparecimento de novas fraturas pelo vertebral fracture assessment (VFA). Na composição corporal por dual-energy X-ray absorptiometry (DXA), houve redução da massa gorda total e melhora no índice de massa magra apendicular pelo Foundation for the National Institutes of Health (FNIH) (p<0,05). A AMO de L3 reduziu significativamente no 6º mês PO, mantendo-se estável no 12º mês PO (p<0,05). Houve redução significativa do VAT, relação VAT/SAT e IHL no seguimento prospectivo (p<0,05). O presente estudo reafirma dados anteriores que mostram que o hipercortisolismo endógeno exerce profundo efeito negativo sobre o esqueleto, em particular sobre o osso trabecular. Além disto, é o primeiro estudo a mostrar que existe correlação negativa entre o TBS com HOMA-IR e AMO; é possível que as alterações do metabolismo energético sejam, pelo menos em parte, responsáveis pelo maior risco de fratura na DC.
The anti-inflammatory and immunosuppressive properties of glucocorticoids (GC) justify the use of these steroids in various clinical conditions, despite its significant adverse effects. Osteoporosis induced by glucocorticoids (OIG) is considered the most important cause of secondary osteoporosis. It is a multifactorial disease involving systemic, tissue and bone cell signaling changes. Furthermore, hypercortisolism is also associated with obesity, redistribution of fat, insulin resistance and diabetes mellitus. Interestingly, these metabolic disorders in which bone mass is preserved, there is increased bone fragility. In recent years, evidence shows various complex interaction between the mineral and energy metabolism, in particular between adipose tissue and bone. In this scenario, Cushing\'s disease (CD) is a desirable clinical model to evaluate various mechanisms involved in the complex process of developing osteoporosis. The objective of this study was to evaluate, in a baseline study and a prospective study, various aspects of the interaction between the mineral and energy metabolism in women with DC and their possible impact on bone mass, as well as the association between bone mass and different types of adipose tissue. In the baseline study, we evaluated three groups of individuals, matched by sex and age: control group (C, n = 27), obese (O; n = 16) and Cushing\'s disease group (CD, n = 16). In the prospective study, we evaluated the CD group at three time points: preoperative (Pre-op; n = 11), 6 months postoperative (6th month PO; n = 10) and 12 months postoperatively (12th month PO; n = 10). In the baseline study, the O and CD groups differed in relation to C as the weight and BMI (p <0.05). The CD group showed significantly higher blood glucose, insulin, glycosylated hemoglobin (HbA1c), HOMA-IR and leptin in relation to the C and O groups (p <0.05). Additionally, the CD group showed lower levels of osteocalcin in relation to the C and O groups (p <0.05) as well as PTH, 25-OH vitamin D (25 (OH) D), and adiponectin in relation to the C group (P <0.05). There was no difference between the groups regarding dosages of IGF-I and preadipocyte factor 1 (Pref-1). The CD group had lower bone mass in the lumbar spine in relation to the C and O groups (p <0.05) and lower bone mass in the total body when compared to the O group (P <0.05). The Trabecular bone score (TBS) was able to show impaired bone quality in groups O and CD, showing greater involvement in CD group (p <0.05). Bone marrow adiposity (BMA) in L3 was significantly higher in the CD group compared to the C and O groups (p <0.05). The CD group showed increased subcutaneous fat content (SAT), visceral (VAT), VAT/SAT ratio and intrahepatic lipid (IHL) in relation to the C group (p<0.05). Additionally, the CD group had a higher content of VAT in relation to the O group (p<0.05). Osteocalcin correlated positively with TBS (r = 0.5, p <0.0001) and negatively with HOMA-IR (r = -0.4, p <0.01) and AMO of L3 (r = - 0.4, p <0.01). The TBS was negatively correlated with HOMA-IR index (r = -0.6, p <0.0001) and AMO of L3 (r = - 0.5, p <0.001). The AMO of L3 positively correlated with BMI (r = 0.4, p <0.01), HOMA-IR (r = 0.3, p <0.05), leptin (r = 0.3, p < 0.05), VAT/SAT ratio (r = 0.6, p <0.0001) and IHL (r = 0.5, p <0.05). In the prospective study, there was a reduction in weight and BMI and blood glucose, insulin, HOMA-IR, glycated hemoglobin and leptin (p <0.05). Additionally, there was increased levels of 25(OH)D, osteocalcin and deoxypyridinoline (p <0.05). There were no significant differences between the levels of adiponectin and Pref-1. The TBS was stable and there was no occurance of new fractures by vertebral fracture assessment (VFA). In body composition by dual-energy X-ray absorptiometry (DXA), threre was a reduction of total fat mass and improvement in apendicular lean body mass index by Foundation for the National Institutes of Health (FNIH) (p <0.05). The BMA of L3 significantly reduced in the 6th month PO, remaining stable on the 12th month PO (p <0.05). There was a significant reduction of VAT, VAT/SAT ratio and IHL in the prospective follow-up (p <0.05). This study confirms previous data showing that endogenous hypercortisolism has a profound negative effect on the skeleton, in particular on trabecular bone. Moreover, it is the first study to show that there is a negative correlation between TBS with HOMA-IR and BMA; it is possible that changes in energy metabolism are at least partly responsible for the increased risk of fracture in DC.

INTRODUÇÃO: A hiperplasia adrenal macronodular independente de ACTH (AIMAH) é uma doença rara, caracterizada pela presença de macronódulos funcionantes nas adrenais e por uma produção aumentada, autônoma e sustentada de cortisol. Constitui uma causa incomum de síndrome de Cushing (SC). A forma esporádica da doença parece ser a mais frequente, no entanto, se desconhece a real prevalência de sua forma familial. Apesar de ser uma entidade clínica conhecida há quase 50 anos, o processo fisiopatológico que culminaria com a AIMAH, as alterações genéticas predisponentes e aspectos clínicos, laboratoriais e radiológicos relevantes da doença ainda não foram elucidados de forma clara. O diagnóstico recente de uma grande família portadora da doença viabilizou a realização do presente trabalho. OBJETIVOS: 1) Caracterizar a evolução da AIMAH em sua forma familial, correlacionando as manifestações clínicas, os dados laboratoriais e os achados radiológicos; 2) investigar a possível associação entre a AIMAH e a ocorrência de meningiomas intracranianos; 3) avaliar a atividade metabólica das adrenais hiperplasiadas na AIMAH; 4) definir o padrão de herança genética da doença na família estudada; e 5) mapear regiões cromossômicas e loci potencialmente relacionados à etiologia genética da AIMAH familial. MÉTODOS: 96 membros da família estudada foram inicialmente submetidos a uma avaliação clínica e laboratorial pormenorizada. Em seguida, foram realizados exames de tomografia computadorizada para a caracterização radiológica das adrenais. Exames de ressonância magnética e de tomografia por emissão de pósitrons com fluordesoxiglicose marcada, acoplada à tomografia computadorizada (18F-FDGPET/CT) foram realizados em pacientes com as formas familial e esporádica da doença para, respectivamente, investigar a presença de meningiomas intracranianos e caracterizar a atividade metabólica das adrenais hiperplasiadas. Foram também realizados testes in vivo para a pesquisa de receptores hormonais aberrantes nos pacientes com a forma familial da doença. Em uma outra etapa do estudo, diferentes técnicas de biologia molecular foram empregadas para a investigação da etiologia genética da AIMAH familial. Desta forma, realizou-se: o sequenciamento do gene do receptor do ACTH (MC2R), um estudo de ligação genética utilizando microssatélites específicos, um estudo de ligação genética em escala genômica utilizando polimorfismos de nucleotídeo único (SNPs) e o sequenciamento de genes suspeitos. RESULTADOS: A avaliação dos indivíduos pertencentes à genealogia permitiu o diagnóstico de 15 casos da doença (7 mulheres e 8 homens) em três gerações consecutivas. A AIMAH era transmitida para as gerações subsequentes tanto pelo sexo masculino como feminino e acometia cerca de metade dos irmãos em alguns segmentos da família. A idade média ao diagnóstico da doença foi de 52,8 +-11,3 anos (32 a 74 anos) e cerca de 86% (12/14) desses pacientes apresentavam SC subclínica. As dosagens do cortisol salivar à meia-noite e do cortisol em urina de 24 horas demonstraram baixa sensibilidade (21% e 14%, respectivamente) para o diagnóstico da doença em sua forma familial. O valor do ACTH plasmático encontrava-se baixo ( < 10 pg/mL) em 46% (5/11) dos pacientes doentes. Em cerca de 62% (8/13) dos casos, foi demonstrada uma redução do valor sérico do sulfato de desidroepiandrosterona (SDHEA). Por regressão logística simples, foi observado que a probabilidade (odds ratio) de um indivíduo apresentar a doença na família era maior diante da presença de pletora, após o diagnóstico de diabetes ou pré-diabetes ou diante do relato de ganho ponderal progressivo. O espessamento de ambas as adrenais associado à presença de nódulos bilaterais foi o achado radiológico mais frequente na forma familial da doença. No entanto, em um terço dos pacientes (5/15) foram encontradas alterações radiológicas em somente uma das adrenais. Durante os testes in vivo para pesquisa de receptores hormonais aberrantes, foram observadas, com frequência, respostas distintas entre os indivíduos doentes pertencentes à família. Nos pacientes submetidos ao exame de ressonância magnética, foram demonstradas imagens típicas de meningiomas intracranianos em um terço (5/15) dos casos. No exame 18F-FDG-PET/CT, foi observado um aumento da atividade metabólica das adrenais hiperplasiadas, tanto nos pacientes com SC manifesta como naqueles com a forma subclínica da doença. O estudo molecular permitiu delimitar nos cromossomos 16 e 11 algumas regiões genômicas potencialmente relacionadas à etiologia genética da AIMAH familial. O sequenciamento de alguns genes suspeitos (GPR56, GPR97 e GPR114), localizados nessas regiões, não demonstrou a presença de mutações. CONCLUSÕES: Na genealogia estudada, o padrão de transmissão da AIMAH foi autossômico dominante, e a SC subclínica foi a forma mais frequente de manifestação da doença. O teste de supressão com 1 mg de dexametasona via oral à meia-noite demonstrou ser o exame laboratorial de escolha para a avaliação inicial dos pacientes suspeitos de apresentarem AIMAH familial, em função, sobretudo, da baixa sensibilidade do cortisol salivar à meia-noite e do cortisol urinário para o diagnóstico da doença. Valores normais do ACTH plasmático foram um achado laboratorial frequente na AIMAH familial e valores baixos do SDHEA sérico demonstraram ser um indício relativamente precoce da SC subclínica associada à doença. Diferentes padrões radiológicos foram demonstrados nas tomografias das adrenais dos pacientes com AIMAH familial, não sendo infrequente a presença de assimetria entre as duas glândulas. Os resultados dos testes in vivo para a pesquisa de receptores hormonais aberrantes foram mais condizentes com a hipótese de que a expressão desses receptores seria um epifenômeno do processo fisiopatológico, resultante da proliferação e desdiferenciação celular. Uma alta prevalência de meningiomas intracranianos foi observada nos pacientes com AIMAH, tanto na forma familial da doença como na forma esporádica. Demonstrou-se também, pela primeira vez, que as adrenais na AIMAH podem exibir uma captação aumentada de 18F-FDG no exame de PET/CT, de forma semelhante às metástases e aos carcinomas da glândula. Por fim, foram delimitadas no cromossomo 16 (16p12.1, 16p11.2, 16q12.1, 16q13 e 16q21) e no cromossomo 11 (11q23.1) as principais regiões do genoma suspeitas de estarem ligadas à etiologia genética da AIMAH familial (genoma de referência: NCBI36/hg18)
INTRODUCTION: ACTH-independent macronodular adrenal hyperplasia (AIMAH) is a rare disease characterized by functioning adrenal macronodules and increased, autonomous and sustained cortisol production. This condition is an uncommon cause of Cushing\'s syndrome (CS). While the sporadic form of the disease appears to be the most frequent, the true prevalence of its familial form is unknown. Despite being a known clinical entity for almost 50 years, the pathophysiological process that leads to AIMAH, the predisposing genetic alterations and important clinical, laboratory and radiological aspects of the disease have not been fully clarified. The recent identification of a large group of relatives with familial AIMAH allowed the accomplishment of the present study. OBJECTIVES: The following were the aims of this study: 1) characterize the development of familial AIMAH through correlations between clinical manifestations, laboratory data and radiological findings; 2) investigate the possible association between AIMAH and the occurrence of intracranial meningioma; 3) characterize the metabolic activity of the adrenal glands in this disease; 4) define the inheritance pattern of the disease in the family studied; and 5) map chromosomal regions and loci potentially related to the genetic etiology of familial AIMAH. METHODS: 96 members of the family studied were initially subjected to a detailed clinical and laboratory evaluation. Computed tomography (CT) scans were performed for the radiological characterization of the adrenal glands. Magnetic resonance imaging scans and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) scans were performed on patients with both forms of the disease (familial and sporadic) to investigate the presence of intracranial meningioma and characterize the metabolic activity of the adrenal glands, respectively. In vivo studies for aberrant hormone receptors were also conducted on those patients with familial AIMAH. In another phase of the study, different molecular biology techniques were employed to investigate the genetic etiology of familial AIMAH. For such, sequencing of the ACTH receptor gene (MC2R), a linkage study using specific microsatellite markers, a single nucleotide polymorphism (SNP)-based genome-wide linkage study and the sequencing of suspect genes were performed. RESULTS: The evaluation of the family revealed the diagnosis of 15 cases of the disease (7 women and 8 men) in three consecutive generations. AIMAH was transmitted to subsequent generations by both genders and half of the siblings were affected in some segments of the family. Mean age at diagnosis was 52.8 +-11.3 years (range: 32 to 74 years) and about 86% (12/14) of the patients exhibited subclinical CS. Both midnight salivary cortisol and 24-hour urinary cortisol demonstrated low sensitivity (21% and 14%, respectively) for the diagnosis of familial AIMAH. Plasma ACTH levels were low ( < 10 pg/ml) in 46% (5/11) of patients with the disease. In about 62% (8/13) of cases, serum dehydroepiandrosterone sulphate (DHEAS) levels were below the normal range. Simple logistic regression models revealed that the probability (odds ratio) of an individual having the disease in the family was greater in the presence of plethora, progressive weight gain or after the diagnosis of diabetes or prediabetes. Adrenal thickening associated with the presence of bilateral nodules was the most common radiological finding in familial AIMAH. However, radiological abnormalities were found in only one of the adrenal glands in one third of the patients (5/15). Throughout the in vivo studies for aberrant hormone receptors, distinct responses were frequently observed among the individuals with familial AIMAH. One third (5/15) of the patients who underwent magnetic resonance imaging scans had typical images of intracranial meningiomas. The 18F-FDG-PET/CT scan revealed increased metabolic activity of the hyperplastic adrenals in patients with both overt and subclinical CS. The molecular studies delimited genomic regions on chromosomes 16 and 11 potentially related to the genetic cause of familial AIMAH. Some suspected genes (GPR56, GPR97 and GPR114), located in these genomic regions, were sequenced, but no mutations were found. CONCLUSIONS: In the extended family studied, AIMAH followed an autosomal dominant pattern of inheritance and subclinical CS was the most common presentation of the disease. The 1 mg overnight dexamethasone suppression test proved to be the screening test of choice for the initial evaluation of patients suspected to have familial AIMAH, due mainly to the low sensitivity of midnight salivary cortisol and 24-hour urinary cortisol as screening tests. A normal level of plasma ACTH was a common laboratory finding in familial AIMAH. Low serum levels of DHEAS proved to be a relatively early finding associated with the subclinical CS determined by the disease. Adrenal CT scans revealed different radiological patterns among patients with familial AIMAH, with a fairly frequent rate of asymmetry between glands. The distinct responses observed throughout the in vivo studies for aberrant hormone receptors, among family members, favor the hypothesis that these receptors may be an epiphenomenon resulting from cell proliferation and dedifferentiation. An increased prevalence of intracranial meningioma was demonstrated in both the familial and sporadic forms of AIMAH. For the first time, it was shown that AIMAH may exhibit increased 18FFDG uptake on the PET/CT scan, similarly to adrenal carcinoma and metastasis. The main genomic regions potentially associated with familial AIMAH were delimited on chromosome 16 (16p12.1, 16p11.2, 16q12.1, 16q13 and 16q21) and chromosome 11 (11q23.1) (reference genome: NCBI36/hg18)

Los estudios descritos en esta tesis se centran en las consecuencias neuropsicológicas de quienes han sufrido síndrome de Cushing (SC, debido al exceso de glucocorticoides) y acromegalia (debido al exceso de hormona de crecimiento -GH-). Las evidencias muestran que la exposición prolongada a glucocorticoides puede tener efectos adversos en pacientes con SC, los cuales no recuperan el nivel de funcionamiento y la calidad de vida después de años de curación. Por otro lado, en los pacientes con acromegalia, los potenciales efectos negativos de la GH sobre la personalidad, la cognición y el comportamiento apenas han sido considerados hasta hace poco. Tomar decisiones es un comportamiento habitual de la vida diaria y requiere seleccionar una opción entre varias posibilidades. El Iowas gambling Task (IGT) es una medida de toma de decisiones que pretende imitar situaciones de la vida real que implican incertidumbre, recompensas y sanciones. La corteza frontal tiene un rol clave en el IGT porque posee la habilidad de coordinar el procesamiento de millones de neuronas para dirigirlas a conseguir metas futuras y tomar decisiones ventajosas. Los objetivos de estos estudios son evaluar la toma de decisiones y la memoria en pacientes con SC y acromegalia, y explorar sus relaciones con la corteza frontal y los problemas afectivos. Se evaluaron 35 pacientes con SC y 35 controles sanos usando el IGT y una resonancia magnética 3Tesla para medir la corteza frontal. Treinta y un pacientes con acromegalia y 31 controles sanos fueron evaluados con el IGT, el RAVLT (Rey Auditory Verbal Learning Test), el STAI (State-Trait Anxiety Inventory) y el BDI-II (Beck Depression Inventory-II). En el primer estudio, los pacientes con SC presentaron estrategias de toma de decisiones alteradas, elegían menos cartas seguras y más cartas de riesgo. Mostraron más dificultades que los controles en aprender los perfiles correctos de ganancias y pérdidas de cada grupo de cartas. En el análisis cerebral completo, los pacientes con SC mostraron adelgazamiento del grosor cortical en la corteza frontal superior izquierda, la corteza precentral izquierda, la corteza insular izquierda, la corteza cingulada anterior izquierda y derecha y la corteza frontal medial caudal derecha, en comparación con los controles sanos. En el segundo estudio, los pacientes acromegálicos mostraron peor memoria verbal a largo plazo y más síntomas de depresión y ansiedad que los controles sanos. Respecto al IGT, los pacientes con acromegalia presentaron una alteración en la estrategia de toma de decisiones en comparación con los controles, elegían menos cartas seguras y más cartas de riesgo. Múltiples correlaciones fueron encontradas entre los síntomas depresivos y ansiosos y la ejecución en memoria y toma de decisiones. Estos estudios muestran una peor toma de decisiones en pacientes con SC y acromegalia. Los pacientes seleccionaban más opciones desfavorables que ventajosas. Mientras los controles sanos aprendían gradualmente a favor de las opciones ventajosas, los pacientes con SC y acromegalia continuaban obteniendo sanciones a lo largo de la tarea. No obtuvimos relación directa entre mala toma de decisiones y adelgazamiento de la corteza frontal, a diferencia de estudios previos en otras patologías. Los déficits en el IGT correlacionaron con los problemas de memoria en pacientes con CS y acromegalia. Además, los pacientes con acromegalia mostraron alteraciones emocionales (ansiedad y síntomas depresivos) que influenciaron la memoria a largo plazo y la toma de decisiones.
The studies described in this thesis focus on the neuropsychological consequences in patients who have suffered Cushing’s syndrome (CS, due to glucocorticoid excess) and acromegaly (due to excess of growth hormone -GH-). It is known that prolonged exposure to glucocorticoids may have long-lasting adverse effects in CS patients who do not completely return to premorbid level of functioning and quality of life despite long-term cure. On the other hand, in acromegalic patients, potential long-lasting effects of GH on the brain affecting personality, cognition and behaviour have not been considered until recently. Making a choice is a common behavior in daily life and requires selecting one option among several alternative possibilities. The Iowa Gambling Task (IGT) is a measurement of decision making that mimics real-life risk taking situations since it involves uncertainty, reward and punishment. Frontal cortex has a key role in the IGT because it has the ability to coordinate processing among its millions of neurons in order to direct them towards future goals and advantageous decisions. The aims of these studies were to evaluate memory and decision making in patients with CS and acromegaly, and explore their relationship with frontal cortex and affective disorders. Thirty-five CS patients and thirty-five matched controls were evaluated using the IGT and 3Tesla magnetic resonance imaging (MRI) to assess frontal cortical thickness. Thirty-one patients with acromegaly and thirty-one healthy controls were evaluated using the IGT, Rey Auditory Verbal Learning Test (RAVLT), State-Trait Anxiety Inventory (STAI) and Beck Depression Inventory-II (BDI-II). In the first study, CS patients presented an altered decision-making strategy compared to controls, choosing a lower number of the safer cards and higher number of riskier cards. They showed more difficulties than controls to learn the correct profiles of wins and losses for each card group. In whole brain analysis, CS patients showed decreased cortical thickness in the left superior frontal cortex, left precentral cortex, left insular cortex, left and right rostral anterior cingulate cortex, and right caudal middle frontal cortex compared to controls. In the second study, acromegalic patients showed impairments in delayed verbal memory and more anxiety and depressive symptoms than controls. Regarding the IGT, acromegalic patients presented an altered decision-making strategy compared to controls, choosing a lower number of the safer cards and higher number of the riskier cards. Multiple correlations between anxiety and depressive symptoms and performance in memory and decision making were found. These studies show impaired decision making in both CS and acromegalic patients. They selected more disadvantageous choices than advantageous choices. Whereas healthy controls gradually learned to favor the advantageous decks, patients with acromegaly and CS continued to experience large punishment throughout training. We have not found a direct relationship between poor decision making and frontal cortical thinning in CS patients, opposite to previous studies on other clinical conditions. Decision deficits on the IGT were correlated with memory deficits in CS and acromegalic patients. Moreover, acromegalic patients show affective alterations (anxiety and depressive symptoms) that influenced delayed memory and decision making.

Appropriate regulation of gene expression is necessary for correct development and homeostasis of organisms. Epigenetic mechanisms represent an additional layer of information, besides the genetic sequence, crucial for the correct functioning of each cell. Histone modifications, which modulate and are associated to transcriptional activation or repression, are a major epigenetic feature. Thanks to predictive modelling, we have studied which histone modifications relate better to enhancer or promoter function in mouse embryonic stem cells, during differentiation and in animal development. We have found that different histone modifications relate better to enhancers or promoters, respectively. We have studied the role of poised enhancers during differentiation and development. We have seen that poised enhancer activation is not exclusive of the neural lineage, but a general mechanism implicated in differentiation of every cell type. We have characterized the epigenetic landscape of Cushing’s syndrome. We have found persistent epigenetic and transcriptional alterations after long-term remission of the disease, related to a deep alteration of the circadian rhythm. These findings promise to be relevant for future therapeutic advances.
Una regulació apropiada de l’expressió gènica és necessària per a un correcte desenvolupament i homeòstasi dels organismes. Els mecanismes epigenètics representen una informació addicional, a més de la seqüència genètica, crucial per al correcte funcionament de cada cèl·lula. Les modificacions d’histones, que modulen i s’associen a activació o repressió transcripcionals, són una característica epigenètica important. Gràcies al modelatge predictiu, hem estudiat quines modificacions d’histones es relacionen millor amb la funció dels enhancers o promotors en cèl·lules mare embrionàries de ratolí, durant la diferenciació i en el desenvolupament animal. Hem trobat que modificacions d’histones diferents es relacionen millor amb enhancers o promotors, respectivament. Hem estudiat el rol dels poised enhancers durant la diferenciació i el desenvolupament. Hem vist que l’activació dels poised enhancers no és exclusiva del llinatge neural, sinó un mecanisme implicat en la diferenciació de tot tipus cel·lular. Hem caracteritzat el paisatge epigenètic de la síndrome de Cushing. Hem trobat alteracions epigenètiques i transcripcionals després d’una remissió de la malaltia a llarg termini, relacionades amb una profunda alteració del ritme circadiari. Aquestes troballes prometen ser rellevants per a futurs avenços terapèutics.