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1.
Am J Physiol Endocrinol Metab ; 326(5): E626-E639, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38536037

RESUMO

Loss of ovarian function imparts increased susceptibility to obesity and metabolic disease. These effects are largely attributed to decreased estradiol (E2), but the role of increased follicle-stimulating hormone (FSH) in modulating energy balance has not been fully investigated. Previous work that blocked FSH binding to its receptor in mice suggested this hormone may play a part in modulating body weight and energy expenditure after ovariectomy (OVX). We used an alternate approach to isolate the individual and combined contributions of FSH and E2 in mediating energy imbalance and changes in tissue-level metabolic health. Female Wistar rats were ovariectomized and given the gonadotropin releasing hormone (GnRH) antagonist degarelix to suppress FSH production. E2 and FSH were then added back individually and in combination for a period of 3 wk. Energy balance, body mass composition, and transcriptomic profiles of individual tissues were obtained. In contrast to previous studies, suppression and replacement of FSH in our paradigm had no effect on body weight, body composition, food intake, or energy expenditure. We did, however, observe organ-specific effects of FSH that produced unique transcriptomic signatures of FSH in retroperitoneal white adipose tissue. These included reductions in biological processes related to lipogenesis and carbohydrate transport. In addition, rats administered FSH had reduced liver triglyceride concentration (P < 0.001), which correlated with FSH-induced changes at the transcriptomic level. Although not appearing to modulate energy balance after loss of ovarian function in rats, FSH may still impart tissue-specific effects in the liver and white adipose tissue that might affect the metabolic health of those organs.NEW & NOTEWORTHY We find no effect of follicle-stimulating hormone (FSH) on energy balance using a novel model in which rats are ovariectomized, subjected to gonadotropin-releasing hormone antagonism, and systematically given back FSH by osmotic pump. However, tissue-specific effects of FSH on adipose tissue and liver were observed in this study. These include unique transcriptomic signatures induced by the hormone and a stark reduction in hepatic triglyceride accumulation.


Assuntos
Metabolismo Energético , Estradiol , Hormônio Foliculoestimulante , Ovariectomia , Ratos Wistar , Animais , Feminino , Metabolismo Energético/efeitos dos fármacos , Ratos , Hormônio Foliculoestimulante/metabolismo , Estradiol/farmacologia , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Ovário/efeitos dos fármacos , Ovário/metabolismo , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos
2.
Int J Cancer ; 153(1): 210-223, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36971100

RESUMO

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with a high risk of relapse and metastatic spread. The actin-bundling protein fascin (FSCN1) is overexpressed in aggressive ACC and represents a reliable prognostic indicator. FSCN1 has been shown to synergize with VAV2, a guanine nucleotide exchange factor for the Rho/Rac GTPase family, to enhance the invasion properties of ACC cancer cells. Based on those results, we investigated the effects of FSCN1 inactivation by CRISPR/Cas9 or pharmacological blockade on the invasive properties of ACC cells, both in vitro and in an in vivo metastatic ACC zebrafish model. Here, we showed that FSCN1 is a transcriptional target for ß-catenin in H295R ACC cells and that its inactivation resulted in defects in cell attachment and proliferation. FSCN1 knock-out modulated the expression of genes involved in cytoskeleton dynamics and cell adhesion. When Steroidogenic Factor-1 (SF-1) dosage was upregulated in H295R cells, activating their invasive capacities, FSCN1 knock-out reduced the number of filopodia, lamellipodia/ruffles and focal adhesions, while decreasing cell invasion in Matrigel. Similar effects were produced by the FSCN1 inhibitor G2-044, which also diminished the invasion of other ACC cell lines expressing lower levels of FSCN1 than H295R. In the zebrafish model, metastases formation was significantly reduced in FSCN1 knock-out cells and G2-044 significantly reduced the number of metastases formed by ACC cells. Our results indicate that FSCN1 is a new druggable target for ACC and provide the rationale for future clinical trials with FSCN1 inhibitors in patients with ACC.


Assuntos
Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Animais , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma Adrenocortical/tratamento farmacológico , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Peixe-Zebra
3.
J Biol Chem ; 296: 100125, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33243834

RESUMO

Caloric restriction (CR) improves health span and life span of organisms ranging from yeast to mammals. Understanding the mechanisms involved will uncover future interventions for aging-associated diseases. In budding yeast, Saccharomyces cerevisiae, CR is commonly defined by reduced glucose in the growth medium, which extends both replicative and chronological life span (CLS). We found that conditioned media collected from stationary-phase CR cultures extended CLS when supplemented into nonrestricted (NR) cultures, suggesting a potential cell-nonautonomous mechanism of CR-induced life span regulation. Chromatography and untargeted metabolomics of the conditioned media, as well as transcriptional responses associated with the longevity effect, pointed to specific amino acids enriched in the CR conditioned media (CRCM) as functional molecules, with L-serine being a particularly strong candidate. Indeed, supplementing L-serine into NR cultures extended CLS through a mechanism dependent on the one-carbon metabolism pathway, thus implicating this conserved and central metabolic hub in life span regulation.


Assuntos
Restrição Calórica , Carbono/metabolismo , Saccharomyces cerevisiae/metabolismo , Serina/metabolismo , Ciclo Celular/fisiologia , Meios de Cultura , Replicação do DNA , Longevidade , Metaboloma , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/crescimento & desenvolvimento
4.
Hum Mol Genet ; 29(14): 2435-2450, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32620954

RESUMO

Dysfunction of the gonadotropin-releasing hormone (GnRH) axis causes a range of reproductive phenotypes resulting from defects in the specification, migration and/or function of GnRH neurons. To identify additional molecular components of this system, we initiated a systematic genetic interrogation of families with isolated GnRH deficiency (IGD). Here, we report 13 families (12 autosomal dominant and one autosomal recessive) with an anosmic form of IGD (Kallmann syndrome) with loss-of-function mutations in TCF12, a locus also known to cause syndromic and non-syndromic craniosynostosis. We show that loss of tcf12 in zebrafish larvae perturbs GnRH neuronal patterning with concomitant attenuation of the orthologous expression of tcf3a/b, encoding a binding partner of TCF12, and stub1, a gene that is both mutated in other syndromic forms of IGD and maps to a TCF12 affinity network. Finally, we report that restored STUB1 mRNA rescues loss of tcf12 in vivo. Our data extend the mutational landscape of IGD, highlight the genetic links between craniofacial patterning and GnRH dysfunction and begin to assemble the functional network that regulates the development of the GnRH axis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Hormônio Liberador de Gonadotropina/genética , Síndrome de Kallmann/genética , Ubiquitina-Proteína Ligases/genética , Proteínas de Peixe-Zebra/genética , Adulto , Idoso , Animais , Modelos Animais de Doenças , Feminino , Genes Dominantes/genética , Hormônio Liberador de Gonadotropina/deficiência , Haploinsuficiência/genética , Humanos , Síndrome de Kallmann/patologia , Masculino , Pessoa de Meia-Idade , Mutação/genética , Neurônios/metabolismo , Neurônios/patologia , Fenótipo , Peixe-Zebra/genética
5.
Clin Obstet Gynecol ; 64(4): 784-792, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560765

RESUMO

Biopotent androgens such as testosterone circulate in low levels in women. However, androgen precursors, such as dehyroepiandrosterone, are among the most abundant hormones produced in both men and women. While testosterone exerts obvious phenotypic effects in men and is essential for male sexual function, considerable debate and controversy abounds over the role of androgens in women and whether androgens exert an analogous role in women as they do in men. This piece reviews androgen economy in women and the clinical case for and against androgen treatment for women for specific indications.


Assuntos
Androgênios , Ciclismo , Animais , Feminino , Humanos , Masculino , Testosterona
6.
Rev Endocr Metab Disord ; 21(4): 667-678, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32914330

RESUMO

The 13th Acromegaly Consensus Conference was held in November 2019 in Fort Lauderdale, Florida, and comprised acromegaly experts including endocrinologists and neurosurgeons who considered optimal approaches for multidisciplinary acromegaly management. Focused discussions reviewed techniques, results, and side effects of surgery, radiotherapy, and medical therapy, and how advances in technology and novel techniques have changed the way these modalities are used alone or in combination. Effects of treatment on patient outcomes were considered, along with strategies for optimizing and personalizing therapeutic approaches. Expert consensus recommendations emphasize how best to implement available treatment options as part of a multidisciplinary approach at Pituitary Tumor Centers of Excellence.


Assuntos
Acromegalia/terapia , Consenso , Agonistas de Dopamina/uso terapêutico , Procedimentos Neurocirúrgicos , Equipe de Assistência ao Paciente , Guias de Prática Clínica como Assunto , Radioterapia , Receptores da Somatotropina/antagonistas & inibidores , Somatostatina/análise , Acromegalia/diagnóstico , Humanos , Procedimentos Neurocirúrgicos/métodos , Procedimentos Neurocirúrgicos/normas , Radioterapia/métodos , Radioterapia/normas
8.
J Sex Med ; 16(9): 1331-1337, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31488288

RESUMO

This Statement is being simultaneously published in the journals Climacteric, Maturitas, Journal of Sexual Medicine, and Journal of Clinical Endocrinology and Metabolism on behalf of the International Menopause Society, The European Menopause and Andropause Society, The International Society for Sexual Medicine, and The Endocrine Society, respectively. This Position Statement has been endorsed by the International Menopause Society, The Endocrine Society, The European Menopause and Andropause Society, The International Society for Sexual Medicine, The International Society for the Study of Women's Sexual Health, The North American Menopause Society, The Federacion Latinoamericana de Sociedades de Climaterio y Menopausia, The Royal College of Obstetricians and Gynaecologists, The International Society of Endocrinology, The Endocrine Society of Australia, and The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.


Assuntos
Androgênios/uso terapêutico , Consenso , Terapia de Reposição Hormonal , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Disfunções Sexuais Psicogênicas/tratamento farmacológico , Testosterona/uso terapêutico , Feminino , Saúde Global , Humanos
9.
Am J Physiol Endocrinol Metab ; 315(2): E316-E325, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29631362

RESUMO

Sex hormones appear to play a role in the regulation of hypothalamic-pituitary-adrenal (HPA) axis activity. The objective was to isolate the effects of estradiol (E2) on central activation of the HPA axis. We hypothesized that the HPA axis response to corticotropin-releasing hormone (CRH) under dexamethasone (Dex) suppression would be exaggerated in response to chronic ovarian hormone suppression and that physiologic E2 add-back would mitigate this response. Thirty premenopausal women underwent 20 wk of gonadotropin-releasing hormone agonist therapy (GnRHAG) and transdermal E2 (0.075 mg per day, GnRHAG + E2, n = 15) or placebo (PL) patch (GnRHAG + PL, n = 15). Women in the GnRHAG + PL and GnRHAG + E2 groups were of similar age (38 (SD 5) yr vs. 36 (SD 7) yr) and body mass index (27 (SD 6) kg/m2 vs. 27 (SD 6) kg/m2). Serum E2 changed differently between the groups ( P = 0.01); it decreased in response to GnRHAG + PL (77.9 ± 17.4 to 23.2 ± 2.6 pg/ml; P = 0.008) and did not change in response to GnRHAG + E2 (70.6 ± 12.4 to 105 ± 30.4 pg/ml; P = 0.36). The incremental area under the curve (AUCINC) responses to CRH were different between the groups for total cortisol ( P = 0.03) and cortisone ( P = 0.04) but not serum adrenocorticotropic hormone (ACTH) ( P = 0.28). When examining within-group changes, GnRHAG + PL did not alter the HPA axis response to Dex/CRH, but GnRHAG + E2 decreased the AUCINC for ACTH (AUCINC, 1,623 ± 257 to 1,211 ± 236 pg/ml·min, P = 0.004), cortisone (1,795 ± 367 to 1,090 ± 281 ng/ml·min, P = 0.009), and total cortisol (7,008 ± 1,387 to 3,893 ± 1,090 ng/ml·min, P = 0.02). Suppression of ovarian hormones by GnRHAG therapy for 20 wk did not exaggerate the HPA axis response to CRH, but physiologic E2 add-back reduced HPA axis activity compared with preintervention levels.


Assuntos
Hormônio Liberador da Corticotropina/farmacologia , Hormônio Liberador de Gonadotropina/agonistas , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Pré-Menopausa/fisiologia , Adiposidade/efeitos dos fármacos , Hormônio Adrenocorticotrópico/sangue , Adulto , Composição Corporal/efeitos dos fármacos , Cortisona/análise , Cortisona/metabolismo , Dexametasona/farmacologia , Método Duplo-Cego , Estradiol/farmacologia , Feminino , Humanos , Hidrocortisona/análise , Hidrocortisona/metabolismo , Pessoa de Meia-Idade
11.
J Biol Chem ; 290(22): 14045-56, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-25873389

RESUMO

The impact of histone deacetylases (HDACs) in the control of gonadotropin releasing hormone (GnRH) neuronal development is unknown. We identified an increase in many HDACs in GT1-7 (differentiated) compared with NLT (undifferentiated) GnRH neuronal cell lines. Increased HDAC9 mRNA and protein and specific deacetylase activity in GT1-7 cells suggested a functional role. Introduction of HDAC9 in NLT cells protected from serum withdrawal induced apoptosis and impaired basal neuronal cell movement. Conversely, silencing of endogenous HDAC9 in GT1-7 cells increased apoptosis and cell movement. Comparison of WT and mutant HDAC9 constructs demonstrated that the HDAC9 pro-survival effects required combined cytoplasmic and nuclear localization, whereas the effects on cell movement required a cytoplasmic site of action. Co-immunoprecipitation demonstrated a novel interaction of HDAC9 selectively with the Class IIb HDAC6. HDAC6 was also up-regulated at the mRNA and protein levels, and HDAC6 catalytic activity was significantly increased in GT1-7 compared with NLT cells. HDAC9 interacted with HDAC6 through its second catalytic domain. Silencing of HDAC6, HDAC9, or both, in GT1-7 cells augmented apoptosis compared with controls. HDAC6 and -9 had additive effects to promote cell survival via modulating the BAX/BCL2 pathway. Silencing of HDAC6 resulted in an activation of movement of GT1-7 cells with induction in acetylation of α-tubulin. Inhibition of HDAC6 and HDAC9 together resulted in an additive effect to increase cell movement but did not alter the acetylation of αtubulin. Together, these studies identify a novel interaction of Class IIa HDAC9 with Class IIb HDAC6 to modulate cell movement and survival in GnRH neurons.


Assuntos
Regulação da Expressão Gênica , Hormônio Liberador de Gonadotropina/metabolismo , Histona Desacetilases/metabolismo , Neurônios/metabolismo , Proteínas Repressoras/metabolismo , Animais , Apoptose , Domínio Catalítico , Linhagem Celular , Movimento Celular , Núcleo Celular/metabolismo , Sobrevivência Celular , Citoplasma/metabolismo , Inativação Gênica , Desacetilase 6 de Histona , Camundongos , Transfecção , Tubulina (Proteína)/metabolismo
13.
FEMS Yeast Res ; 14(1): 73-88, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24164855

RESUMO

The sirtuins are a phylogenetically conserved family of NAD(+) -dependent protein deacetylases that consume one molecule of NAD(+) for every deacetylated lysine side chain. Their requirement for NAD(+) potentially makes them prone to regulation by fluctuations in NAD(+) or biosynthesis intermediates, thus linking them to cellular metabolism. The Sir2 protein from Saccharomyces cerevisiae is the founding sirtuin family member and has been well characterized as a histone deacetylase that functions in transcriptional silencing of heterochromatin domains and as a pro-longevity factor for replicative life span (RLS), defined as the number of times a mother cell divides (buds) before senescing. Deleting SIR2 shortens RLS, while increased gene dosage causes extension. Furthermore, Sir2 has been implicated in mediating the beneficial effects of caloric restriction (CR) on life span, not only in yeast, but also in higher eukaryotes. While this paradigm has had its share of disagreements and debate, it has also helped rapidly drive the aging research field forward. S. cerevisiae has four additional sirtuins, Hst1, Hst2, Hst3, and Hst4. This review discusses the function of Sir2 and the Hst homologs in replicative aging and chronological aging, and also addresses how the sirtuins are regulated in response to environmental stresses such as CR.


Assuntos
Regulação Fúngica da Expressão Gênica , Saccharomyces cerevisiae/fisiologia , Sirtuínas/metabolismo , Modelos Biológicos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo
15.
PM R ; 16(1): 6-13, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37229562

RESUMO

BACKGROUND: Despite the common practice of intraarticular corticosteroid injections (ICSIs) for peripheral joint disease, little is known about their systemic effects on the hypothalamic-pituitary-gonadal axis. OBJECTIVE: To assess the short-term effects of ICSIs on serum testosterone (T), luteinizing hormone (LH), and follicle stimulating hormone (FSH) levels together with changes in Shoulder Pain and Disability Index (SPADI) scores in a veteran population. DESIGN: Prospective pilot study. SETTING: Outpatient musculoskeletal clinic. PARTICIPANTS: Thirty male veterans, median age 50 (range 30-69) years. INTERVENTIONS: Ultrasound-guided glenohumeral joint injection using 3 mL of 1% lidocaine HCl and 1 mL of 40 mg triamcinolone acetonide (Kenalog). OUTCOME MEASURE(S): Serum T, FSH, and LH levels, Quantitative Androgen Deficiency in the Aging Male (qADAM), and SPADI questionnaires at baseline, 1, and 4 week(s) post procedure. RESULTS: At 1 week post injection, serum T levels decreased by 56.8 ng/dL (95% confidence interval (CI): 91.8, 21.7, p = .002) compared with baseline. Between 1 and 4 weeks post injection, serum T levels increased by 63.9 ng/dL (95% CI: 26.5, 101.2, p = .001), recovering to near baseline levels. SPADI scores were reduced at 1 week (-18.3, 95% CI: -24.4, -12.1, p < .001) and 4 weeks (-14.5, 95% CI -21.1, -7.9, p < .001). CONCLUSIONS: A single ICSI can temporarily suppress the male gonadal axis. Future studies are needed to evaluate for long-term effects of multiple injections at a single setting and/or higher corticosteroid doses on male reproductive axis function.


Assuntos
Hormônio Luteinizante , Veteranos , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Triancinolona Acetonida , Hormônio Foliculoestimulante , Projetos Piloto , Estudos Prospectivos , Testosterona , Corticosteroides
16.
JCEM Case Rep ; 2(6): luae094, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38915761

RESUMO

Pheochromocytomas predominantly produce catecholamines, and rarely also produce ACTH, causing Cushing syndrome (CS). Cyclic CS, an uncommon presentation of hypercortisolism, poses a diagnostic challenge. We report a 71-year-old woman who developed cyclic ectopic ACTH secretion from a pheochromocytoma. Previous evaluations showed intermittent elevations in cortisol and ACTH levels, normal pituitary magnetic resonance imaging, and an adrenal nodule. On admission, she was hypertensive and had cushingoid features. Bilateral inferior petrosal sinus sampling with desmopressin stimulation and an 8-mg dexamethasone suppression test suggested ectopic ACTH secretion, but ACTH increased during the peripheral desmopressin stimulation test. Plasma normetanephrines were about 2-fold above the upper reference limit. 18F-fluoro-dopa and 68Gallium-DOTATATE positron emission tomography/computed tomography scans, computed tomography, and magnetic resonance imaging identified an adrenal mass. After doxazosin adrenoceptor blockade, she underwent right adrenalectomy; histopathology and immunohistochemistry confirmed an ACTH-secreting pheochromocytoma. Postoperative blood pressure normalized and serum cortisol and plasma ACTH levels were suppressed, requiring physiologic hydrocortisone replacement. This case underscores the importance of considering pheochromocytoma in ACTH-dependent hypercortisolism with elevated metanephrines and an adrenal mass. Timely diagnosis and treatment can reduce morbidity and improve quality of life.

17.
J Neuropathol Exp Neurol ; 83(7): 586-595, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38777808

RESUMO

Corticotroph adenomas/pituitary neuroendocrine tumors (PitNETs) are associated with significant morbidity and mortality. Predictors of tumor behavior have not shown high prognostic accuracy. For somatotroph adenomas/PitNETs, E-cadherin expression correlates strongly with prognosis. E-cadherin expression has not been investigated in other PitNETs. A retrospective chart review of adults with corticotroph adenomas/PitNETs was conducted to assess correlation between E-cadherin expression and tumor characteristics. In addition, gene expression microarray was performed in subset of tumors (n = 16). Seventy-seven patients were identified; 71% were female, with median age of cohort 45.2 years. Seventy-five percent had macroadenomas, of which 22% were hormonally active. Ninety-five percent of microadenomas were hormonally active. Adrenocorticotropic hormone granulation pattern by IHC identified 63% as densely granulated (DG) and 34% as sparsely granulated (SG). All microadenomas were DG (p < .001); 50% of macroadenomas were DG associated with increased tumor invasion compared to SG. E-cadherin IHC was positive in 80%, diminished in 17%, and absent in 20% and did not correlate with corticotroph PitNETs subtype, size, or prognosis. In contrast to the distinct transcriptomes of corticotroph PitNETs and normal pituitaries, a comparison of clinically active and silent corticotroph PitNETs demonstrated similar molecular signatures indicating their common origin, but with unique differences related to their secretory status.


Assuntos
Adenoma Hipofisário Secretor de ACT , Caderinas , Tumores Neuroendócrinos , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Caderinas/genética , Caderinas/biossíntese , Caderinas/metabolismo , Adulto , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/metabolismo , Estudos Retrospectivos , Adenoma Hipofisário Secretor de ACT/genética , Adenoma Hipofisário Secretor de ACT/patologia , Adenoma Hipofisário Secretor de ACT/metabolismo , Idoso , Transcriptoma , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/metabolismo , Adulto Jovem , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica
18.
J Clin Transl Endocrinol ; 36: 100348, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38756206

RESUMO

Introduction: Feminizing and masculinizing gender-affirming hormone therapy (fGAHT, mGAHT) results in bone mineral density (BMD) maintenance or improvement over time in transgender and gender diverse (TGD) adults. Mostly European TGD studies have explored GAHT's impact on BMD, but the association of BMI and BMD in TGD adults deserves further study. Objective: To determine whether GAHT duration or BMI are associated with BMD and Z-scores among TGD young adults. Methods: Cross-sectional study of nonsmoking TGD adults aged 18-40 years without prior gonadectomy or gonadotropin-releasing hormone agonist (GnRHa) therapy taking GAHT for > 1 year. BMD and Z-scores were collected from dual-energy x-ray absorptiometry. Associations between femoral neck, total hip, and lumbar spine BMDs and Z-scores and the predictors, GAHT duration and BMI, were estimated using linear regression. Results: Among 15 fGAHT and 15 mGAHT, mean BMIs were 27.6 +/- standard deviation (SD) 6.4 kg/m2 and 25.3 +/- 5.9 kg/m2, respectively. Both groups had mean BMDs and Z-scores within expected male and female reference ranges at all three sites. Higher BMI among mGAHT was associated with higher femoral neck and total hip BMDs (femoral neck: ß = 0.019 +/- standard error [SE] 0.007 g/cm2, total hip: ß = 0.017 +/- 0.006 g/cm2; both p < 0.05) and Z-scores using male and female references. GAHT duration was not associated with BMDs or Z-scores for either group. Conclusions: Z-scores in young, nonsmoking TGD adults taking GAHT for > 1 year, without prior gonadectomy or GnRHa, and with mean BMIs in the overweight range, were reassuringly within the expected ranges for age based on male and female references. Higher BMI, but not longer GAHT duration, was associated with higher femoral neck and total hip BMDs and Z-scores among mGAHT. Larger, prospective studies are needed to understand how body composition changes, normal or low BMIs, and gonadectomy affect bone density in TGD adults.

19.
Endocr Connect ; 13(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37992487

RESUMO

Adrenocortical carcinoma (ACC) is an aggressive malignancy with limited treatment options. Polo-like kinase 1 (PLK1) is a promising drug target; PLK1 inhibitors (PLK1i) have been investigated in solid cancers and are more effective in TP53-mutated cases. We evaluated PLK1 expression in ACC samples and the efficacy of two PLK1i in ACC cell lines with different genetic backgrounds. PLK1 protein expression was investigated by immunohistochemistry in tissue samples and correlated with clinical data. The efficacy of rigosertib (RGS), targeting RAS/PI3K, CDKs and PLKs, and poloxin (Pol), specifically targeting the PLK1 polo-box domain, was tested in TP53-mutated NCI-H295R, MUC-1, and CU-ACC2 cells and in TP53 wild-type CU-ACC1. Effects on proliferation, apoptosis, and viability were determined. PLK1 immunostaining was stronger in TP53-mutated ACC samples vs wild-type (P = 0.0017). High PLK1 expression together with TP53 mutations correlated with shorter progression-free survival (P= 0.041). NCI-H295R showed a time- and dose-dependent reduction in proliferation with both PLK1i (P< 0.05at 100 nM RGS and 30 µM Pol). In MUC-1, a less pronounced decrease was observed (P< 0.05at 1000 nM RGS and 100 µM Pol). 100 nM RGS increased apoptosis in NCI-H295R (P< 0.001), with no effect on MUC-1. CU-ACC2 apoptosis was induced only at high concentrations (P < 0.05 at 3000 nM RGS and 100 µM Pol), while proliferation decreased at 1000 nM RGS and 30 µM Pol. CU-ACC1 proliferation reduced, and apoptosis increased, only at 100 µM Pol. TP53-mutated ACC cell lines demonstrated better response to PLK1i than wild-type CU-ACC1. These data suggest PLK1i may be a promising targeted treatment of a subset of ACC patients, pre-selected according to tumour genetic signature.

20.
J Biol Chem ; 287(25): 20957-66, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22539348

RESUMO

Sirtuins are an evolutionarily conserved family of NAD(+)-dependent protein deacetylases that function in the regulation of gene transcription, cellular metabolism, and aging. Their activity requires the maintenance of an adequate intracellular NAD(+) concentration through the combined action of NAD(+) biosynthesis and salvage pathways. Nicotinamide (NAM) is a key NAD(+) precursor that is also a byproduct and feedback inhibitor of the deacetylation reaction. In Saccharomyces cerevisiae, the nicotinamidase Pnc1 converts NAM to nicotinic acid (NA), which is then used as a substrate by the NAD(+) salvage pathway enzyme NA phosphoribosyltransferase (Npt1). Isonicotinamide (INAM) is an isostere of NAM that stimulates yeast Sir2 deacetylase activity in vitro by alleviating the NAM inhibition. In this study, we determined that INAM stimulates Sir2 through an additional mechanism in vivo, which involves elevation of the intracellular NAD(+) concentration. INAM enhanced normal silencing at the rDNA locus but only partially suppressed the silencing defects of an npt1Δ mutant. Yeast cells grown in media lacking NA had a short replicative life span, which was extended by INAM in a SIR2-dependent manner and correlated with increased NAD(+). The INAM-induced increase in NAD(+) was strongly dependent on Pnc1 and Npt1, suggesting that INAM increases flux through the NAD(+) salvage pathway. Part of this effect was mediated by the NR salvage pathways, which generate NAM as a product and require Pnc1 to produce NAD(+). We also provide evidence suggesting that INAM influences the expression of multiple NAD(+) biosynthesis and salvage pathways to promote homeostasis during stationary phase.


Assuntos
Inativação Gênica/efeitos dos fármacos , NAD/metabolismo , Niacinamida/farmacologia , Nicotinamidase/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Sirtuína 2/metabolismo , DNA Fúngico/genética , DNA Fúngico/metabolismo , DNA Ribossômico/genética , DNA Ribossômico/metabolismo , Inativação Gênica/fisiologia , Loci Gênicos/fisiologia , NAD/genética , Niacinamida/metabolismo , Nicotinamidase/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/genética , Sirtuína 2/genética
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