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1.
J Clin Endocrinol Metab ; 109(2): e667-e674, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-37715962

RESUMO

CONTEXT: Treatment of hyperprolactinemia with ergoline dopamine agonists (DAs) can be complicated by intolerance and resistance. OBJECTIVE: This study examines the efficacy and tolerability of the nonergot DA ropinirole for the long-term treatment of hyperprolactinemia. METHODS: Twelve hyperprolactinemic women were treated with ropinirole in a 6-month, open-label, dose-escalation trial; 7 of the 12 continued treatment in an extension study for up to 17 months. Ropinirole doses were uptitrated to achieve normal prolactin (PRL) levels, restore menses, and eliminate galactorrhea. RESULTS: Two of the 12 participants were DA naive; 6 of 12 were ergot DA intolerant; and 1 of 12 had known ergot DA resistance. Baseline PRL levels were 126.2 ± 41.4 ng/mL (SEM). Ropinirole was uptitrated from 0.125 to 0.25 mg/h to a median total daily dose (TDD) of 2 mg/d (1-4 mg/d [interquartile range]). PRL normalization was achieved in 50% of the participants (5 with microadenomas and 1 with idiopathic hyperprolactinemia) at a median effective TDD of 1 mg/d. Of the patients achieving PRL normalization, 83% were ergot DA intolerant. A persistent partial biochemical response (PRL reduction >50% from baseline) was achieved in 17% of the participants. During treatment, menses resumed in 67% of amenorrheic patients; galactorrhea resolved in 67%. Mild adverse effects were reported in 92% of participants; however, ropinirole was not discontinued because of intolerance even among the 50% of individuals with a prior history of ergot DA intolerance and resultant medication discontinuation. CONCLUSION: These data demonstrate the efficacy and tolerability of ropinirole for the treatment of hyperprolactinemia in patients with microprolactinomas and idiopathic hyperprolactinemia and suggest ropinirole may represent a novel therapeutic alternative for treating hyperprolactinemic disorders in patients with ergot DA intolerance.


Assuntos
Amenorreia , Galactorreia , Hiperprolactinemia , Indóis , Neoplasias Hipofisárias , Prolactinoma , Gravidez , Humanos , Feminino , Hiperprolactinemia/tratamento farmacológico , Hiperprolactinemia/etiologia , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/tratamento farmacológico , Prolactinoma/complicações , Prolactinoma/tratamento farmacológico , Agonistas de Dopamina/efeitos adversos , Galactorreia/induzido quimicamente , Galactorreia/tratamento farmacológico , Prolactina
3.
J Clin Endocrinol Metab ; 108(9): 2262-2271, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-36897161

RESUMO

CONTEXT: Individual responses to weight loss (WL) medications vary widely and prediction of response remains elusive. OBJECTIVE: We investigated biomarkers associated with use of lorcaserin (LOR), a 5HT2cR agonist that targets proopiomelanocortin (POMC) neurons that regulate energy and glucose homeostasis, to identify predictors of clinical efficacy. METHODS: Thirty individuals with obesity were treated with 7 days of placebo and LOR in a randomized crossover study. Nineteen participants continued on LOR for 6 months. Cerebrospinal fluid (CSF) POMC peptide measurements were used to identify potential biomarkers that predict WL. Insulin, leptin, and food intake during a meal were also studied. RESULTS: LOR induced a significant decrease in CSF levels of the POMC prohormone and an increase in its processed peptide ß-endorphin after 7 days; ß-endorphin/POMC increased by 30% (P < .001). This was accompanied by a substantial decrease in insulin, glucose, and homeostasis model assessment of insulin resistance before WL. Changes in CSF POMC peptides persisted after WL (6.9%) at 6 months that were distinct from prior reports after diet alone. Changes in POMC, food intake, or other hormones did not predict WL. However, baseline CSF POMC correlated negatively with WL (P = .07) and a cutoff level of CSF POMC was identified that predicted more than 10% WL. CONCLUSION: Our results provide evidence that LOR affects the brain melanocortin system in humans and that effectiveness is increased in individuals with lower melanocortin activity. Furthermore, early changes in CSF POMC parallel WL-independent improvements in glycemic indexes. Thus, assessment of melanocortin activity could provide a way to personalize pharmacotherapy of obesity with 5HT2cR agonists.


Assuntos
Pró-Opiomelanocortina , beta-Endorfina , Humanos , Pró-Opiomelanocortina/líquido cefalorraquidiano , Estudos Cross-Over , Obesidade/tratamento farmacológico , Redução de Peso , Melanocortinas , Glucose , Insulina
4.
J Family Med Prim Care ; 11(5): 1943-1948, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35800530

RESUMO

Introduction: Family planning is one of the essential health care services to promote and ensure reproductive health. Nearly 40.2 percent of men think it as a woman's responsibility as per the National Family Health Survey 4. Not much attention has been given to the male partners in the usage of contraceptives. So, this study was conducted to assess the male participation in family planning among married males in a rural area of Chhattisgarh. Methodology: A sample of 365 married males were interviewed through a semi-structured questionnaire at a primary health care center. Results: Only 48 (13.1%) participants were using condoms or male sterilization as a method of contraception at the time of the study. Good involvement of males in family planning was found to be (10.9%) in our study. Those who were above the poverty line and educated (graduation and above) had good involvement in family planning. The chief reason cited for not opting for male sterilization by participants was fear of physical weakness followed by family opposition. Conclusion: The socio-cultural barrier in itself demotivates men from getting involved in the family planning program. This study recommends increasing health literacy regarding family planning among men by including it in the school curriculum and through awareness activities and counseling that influences them positively and motivates them to accept contraceptive services and shared decision making. Sterilization facilities should be made accessible to them to further encourage them.

5.
J Clin Endocrinol Metab ; 106(12): e5156-e5164, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34255061

RESUMO

INTRODUCTION: Pregnancy is characterized by increased appetitive drive beginning early in gestation, yet the central mechanisms underlying this adaptation are poorly understood in humans. To elucidate central mechanisms underlying appetite regulation in early pregnancy, we examine plasma and cerebrospinal fluid (CSF) leptin and Agouti-related peptide (AgRP) as well as CSF proopiomelanocortin (POMC) as surrogates for brain melanocortin activity. METHODS: Plasma leptin, soluble leptin receptor, AgRP, and CSF leptin, POMC, and AgRP were collected from pregnant women before cerclage placement (16.6 ±â€…1.1 weeks; N = 24), scheduled cesarean section (39.2 ±â€…0.2 weeks; N = 24), and from nonpregnant controls (N = 24), matched for age and body mass index. RESULTS: Plasma leptin was 1.5 times higher in pregnancy vs controls (P = 0.01), but CSF leptin did not differ. CSF/plasma leptin percentage was lower in early pregnancy vs controls (0.8 ±â€…0.1 vs 1.7 ±â€…0.2; P < 0.0001) and remained unchanged at term (0.9 ±â€…0.1), supporting a decrease in leptin transport into CSF in pregnancy. Plasma AgRP, a peripheral biomarker of the orexigenic hypothalamic neuropeptide, was higher in early pregnancy vs controls (95.0 ±â€…7.8 vs 67.5 ±â€…5.3; P = 0.005). In early gestation, CSF AgRP did not differ from controls, but CSF POMC was 25% lower (P = 0.006). In contrast, at term, CSF AgRP was 42% higher vs controls (P = 0.0001), but CSF POMC no longer differed. Overall, the CSF AgRP/POMC ratio was 1.5-fold higher in early pregnancy vs controls, reflecting a decrease in melanocortin tone favoring appetitive drive. CONCLUSIONS: Pregnancy-specific adaptions in the central regulation of energy balance occur early in human gestation and are consistent with decreased leptin transport into brain and resistance to the effects of leptin on target melanocortin neuropeptides.


Assuntos
Adaptação Fisiológica , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Metabolismo Energético , Melanocortinas/análise , Neuropeptídeos/análise , Adulto , Proteína Relacionada com Agouti/sangue , Proteína Relacionada com Agouti/líquido cefalorraquidiano , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Leptina/sangue , Leptina/líquido cefalorraquidiano , Melanocortinas/sangue , Melanocortinas/líquido cefalorraquidiano , Neuropeptídeos/sangue , Neuropeptídeos/líquido cefalorraquidiano , Gravidez , Pró-Opiomelanocortina/sangue , Pró-Opiomelanocortina/líquido cefalorraquidiano , Prognóstico , Receptores para Leptina/sangue
6.
Cell Signal ; 86: 110091, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34298089

RESUMO

Metastatic progression is the key feature of prostate cancer primarily responsible for mortality caused by this disease. RAD9 is an oncogene for prostate cancer, and the encoded protein enhances metastasis-related phenotypes. RAD9 is a transcription factor with a limited set of regulated target genes, but the complete list of downstream genes critical for prostate carcinogenesis is unknown. We used microarray gene expression profiling and chromatin immunoprecipitation in parallel to identify genes transcriptionally controlled by RAD9 that contribute to this cancer. We found expression of 44 genes altered in human prostate cancer DU145 cells when RAD9 is knocked down by siRNA, and all of them bind RAD9 at their genomic location. FOXP1 and NDRG1 were down regulated when RAD9 expression was reduced, and we evaluated them further. We demonstrate that reduced RAD9, FOXP1 or NDGR1 expression decreases cell proliferation, rapid migration, anchorage-independent growth, anoikis resistance, and aerobic glycolysis. Ectopic expression of FOXP1 or NDRG1 partially restored aerobic glycolysis to prostate cancer cells with reduced RAD9 abundance, but only FOXP1 significantly complemented the other deficiencies. We thus show, for the first time, that RAD9 regulates FOXP1 and NDRG1 expression, and they function differently as downstream effectors for RAD9-mediated prostate cancer cell activities.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias da Próstata , Linhagem Celular Tumoral , Proliferação de Células , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Humanos , Masculino , Neoplasias da Próstata/patologia , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo
7.
Mol Cancer Ther ; 19(12): 2502-2515, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33082276

RESUMO

Agents targeting metabolic pathways form the backbone of standard oncology treatments, though a better understanding of differential metabolic dependencies could instruct more rationale-based therapeutic approaches. We performed a chemical biology screen that revealed a strong enrichment in sensitivity to a novel dihydroorotate dehydrogenase (DHODH) inhibitor, AG-636, in cancer cell lines of hematologic versus solid tumor origin. Differential AG-636 activity translated to the in vivo setting, with complete tumor regression observed in a lymphoma model. Dissection of the relationship between uridine availability and response to AG-636 revealed a divergent ability of lymphoma and solid tumor cell lines to survive and grow in the setting of depleted extracellular uridine and DHODH inhibition. Metabolic characterization paired with unbiased functional genomic and proteomic screens pointed to adaptive mechanisms to cope with nucleotide stress as contributing to response to AG-636. These findings support targeting of DHODH in lymphoma and other hematologic malignancies and suggest combination strategies aimed at interfering with DNA-damage response pathways.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Neoplasias Hematológicas/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Pirimidinas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Di-Hidro-Orotato Desidrogenase , Genômica/métodos , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/etiologia , Neoplasias Hematológicas/patologia , Humanos , Estadiamento de Neoplasias , Proteômica/métodos
8.
J Family Med Prim Care ; 9(2): 619-625, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32318392

RESUMO

BACKGROUND AND AIMS: Breast and cervical cancers are two of the most common cancer diagnosed and are leading cause of death among females. Mortality and complication rates are higher in countries with lower awareness regarding breast and cervical cancer. The aim of this study is to assess the community inquisitive insight regarding breast and cervical carcinoma after sensitising them with health education. SETTING AND DESIGN: This is a qualitative research done on adolescent school going girls. The analysis is done using the verbal and written queries during group interaction sessions after the health education regarding breast and cervical cancer was imparted. RESULTS AND CONCLUSION: A community specific health education material regarding breast and cervical cancers should include information regarding normal physiological process like menstruation, available preventive, and screening and management modalities of common cancers, the explanations for myths and redressal of stigma prevailing in the specific community.

9.
J Alzheimers Dis ; 75(2): 471-482, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32250301

RESUMO

BACKGROUND: Concentrations of soluble amyloid-ß (Aß) oscillate with the sleep-wake cycle in the interstitial fluid of mice and cerebrospinal fluid (CSF) of humans. Further, the concentration of Aß in CSF increases during sleep deprivation. Stress and disruption of the circadian clock are additional mechanisms hypothesized to increase CSF Aß levels. Cortisol is a marker for stress and has an endogenous circadian rhythm. Other factors such as glucose and lactate have been associated with changes in sleep-wake activity and/or Aß. OBJECTIVE: In this exploratory study, we used samples collected in a previous study to examine how sleep deprivation affects Aß, cortisol, lactate, and glucose in plasma and CSF from healthy middle-aged adults (N = 11). METHODS: Eleven cognitively normal participants without evidence of sleep disturbance were randomized to sleep deprivation or normal sleep control. All participants were invited to repeat the study. Cortisol, lactate, glucose, and Aß were measured in 2-h intervals over a 36-h period in both plasma and CSF. All concentrations were normalized to the mean prior to calculating mesor, amplitude, acrophase, and other parameters. RESULTS: One night of sleep deprivation increases the overnight concentration of Aß in CSF approximately 10%, but does not significantly affect cortisol, lactate, or glucose concentrations in plasma or CSF between the sleep-deprived and control conditions. CONCLUSION: These data suggest that sleep deprivation-related changes in CSF Aß are not mediated by stress or circadian disruption as measured by cortisol.


Assuntos
Peptídeos beta-Amiloides/líquido cefalorraquidiano , Ritmo Circadiano/fisiologia , Privação do Sono/líquido cefalorraquidiano , Sono/fisiologia , Estresse Fisiológico/fisiologia , Estresse Psicológico/líquido cefalorraquidiano , Adulto , Cognição/fisiologia , Feminino , Glucose/líquido cefalorraquidiano , Humanos , Hidrocortisona/líquido cefalorraquidiano , Ácido Láctico/líquido cefalorraquidiano , Masculino , Pessoa de Meia-Idade
10.
J Family Med Prim Care ; 9(11): 5484-5489, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33532383

RESUMO

SARS CoV2 is an emerging infectious pandemic. The preemptive measures taken to curtail the spread has its effects far and wide across different sectors and all age groups. The most unspoken sufferers are adolescents. In this article, we have reflected on how adolescent issues addressed by the government's dynamism, have had collateral damage due to the COVID initiatives. Globally, around 89% are currently not in school because of COVID-19. They will pave a way to unforeseen collateral effects on the physical, social, psychological health, and future of the young minds. From an increase in school drop-outs, interrupted learning, worsening of the gender gap in education to technology dependence and addictions, this pandemic is going to unravel the uninvited social evils. The regular benefits of adolescents from the government have not been paid heed to. Supply of IFA tablets, sanitary napkins, provision of supplementary nutrition, health education, and implementation of immunization activities are a few of the services to mention which are being hampered. We have recommended a few strategies like establishing the peer educator system in disseminating COVID-related awareness, engaging them in a smooth public distribution system, and act as a potential linkage for the families in distress. We have proposed a few modus operandi like direct cash transfer or food supplements as take-home rations will be able to sustain the nutrition of the adolescents to keep the flow of uninterrupted amenities to adolescents in education, nutrition, mental health, personal hygiene, and other such sectors.

11.
J Clin Endocrinol Metab ; 105(4)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31838496

RESUMO

CONTEXT: Cortisol in blood has a robust circadian rhythm and exerts potent effects on energy balance that are mediated in part by central mechanisms. These interactions involve orexigenic agouti-related protein (AgRP) neurons that are stimulated by glucocorticoids. However, diurnal changes in brain or cerebrospinal fluid (CSF) cortisol and cortisone, which are interconverted by 11ß-HSD1, have not been characterized in humans. OBJECTIVE: To conduct a secondary analysis of existing samples to characterize diurnal changes in cortisol and cortisone in CSF and examine their relationships to changes in AgRP. METHODS: Stored CSF and plasma samples were obtained from 8 healthy subjects who served as controls for a sleep study. CSF was collected every 2h for 36h via indwelling lumbar catheter; plasma was collected every 2h. RESULTS: There was a diurnal rhythm for cortisol and cortisone in CSF that closely followed the plasma rhythm by 2 h with peak and nadir levels at 0900h and 0100h. The ratio of cortisol (active) to cortisone (inactive) in CSF was 48% higher at the peak versus nadir. There was a diurnal rhythm for AgRP in plasma that was out of phase with the cortisol rhythm. There was a less distinct diurnal rhythm for AgRP in CSF that oscillated with a similar phase as cortisol. CONCLUSIONS: There is a robust diurnal rhythm for cortisol and cortisone in CSF. Diurnal changes were noted for AgRP that are related to the cortisol changes. It remains to be determined if AgRP mediates adverse metabolic effects associated with disruption of the cortisol circadian rhythm.


Assuntos
Proteína Relacionada com Agouti/análise , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Ritmo Circadiano , Cortisona/análise , Hidrocortisona/análise , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
12.
Nutr Diabetes ; 9(1): 29, 2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31611548

RESUMO

BACKGROUND: Proopiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus (ARH) control energy homeostasis by sensing hormonal and nutrient cues and activating secondary melanocortin sensing neurons. We identified the expression of a G protein-coupled receptor, Gpr17, in the ARH and hypothesized that it contributes to the regulatory function of POMC neurons on metabolism. METHODS: In order to test this hypothesis, we generated POMC neuron-specific Gpr17 knockout (PGKO) mice and determined their energy and glucose metabolic phenotypes on normal chow diet (NCD) and high-fat diet (HFD). RESULTS: Adult PGKO mice on NCD displayed comparable body composition and metabolic features measured by indirect calorimetry. By contrast, PGKO mice on HFD demonstrated a sexually dimorphic phenotype with female PGKO mice displaying better metabolic homeostasis. Notably, female PGKO mice gained significantly less body weight and adiposity (p < 0.01), which was associated with increased energy expenditure, locomotor activity, and respiratory quotient, while males did not have an overt change in energy homeostasis. Though PGKO mice of both sexes had comparable glucose and insulin tolerance, detailed analyses of liver gene expression and serum metabolites indicate that PGKO mice could have reduced gluconeogenesis and increased lipid utilization on HFD. To elucidate the central-based mechanism(s) underlying the better-preserved energy and glucose homeostasis in PGKO mice on HFD, we examined the electrophysiological properties of POMC neurons and found Gpr17 deficiency led to increased spontaneous action potentials. Moreover, PGKO mice, especially female knockouts, had increased POMC-derived alpha-melanocyte stimulating hormone and beta-endorphin despite a comparable level of prohormone POMC in their hypothalamic extracts. CONCLUSIONS: Gpr17 deficiency in POMC neurons protects metabolic homeostasis in a sex-dependent manner during dietary and aging challenges, suggesting that Gpr17 could be an effective anti-obesity target in specific populations with poor metabolic control.


Assuntos
Peso Corporal/fisiologia , Encéfalo/metabolismo , Resistência à Insulina/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Pró-Opiomelanocortina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Envelhecimento/metabolismo , Animais , Dieta Hiperlipídica , Metabolismo Energético/fisiologia , Feminino , Homeostase/fisiologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Knockout , Atividade Motora/fisiologia , Proteínas do Tecido Nervoso/genética , Receptores Acoplados a Proteínas G/genética , Fatores Sexuais
13.
J Clin Endocrinol Metab ; 104(11): 5453-5461, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31361303

RESUMO

CONTEXT: GH activates agouti-related protein (AgRP) neurons, leading to orexigenic responses in mice. The relationship between serum GH and plasma AgRP, which has been shown to reflect hypothalamic AgRP, has not been evaluated in humans. OBJECTIVE: To test the hypothesis that central stimulatory actions of GH on hypothalamic AgRP could be reflected in plasma AgRP in acromegaly. METHODS: We studied 23 patients with active acromegaly before and for ≤2 years after surgical (n = 13) or GH receptor antagonist therapy with pegvisomant (n = 10), and 100 healthy subjects with morning fasting blood samples for AgRP, leptin, GH, and IGF-1 and anthropometric measurements. RESULTS: The plasma AgRP levels were higher in those with active acromegaly than in the matched healthy subjects [median, 100 pg/mL; interquartile range (IQR), 78 to 139 pg/mL vs median, 63 pg/mL; IQR, 58 to 67 pg/mL; P < 0.0001]. Plasma AgRP decreased from before to after surgery (median, 102 pg/mL; IQR, 82 to 124 pg/mL vs median, 63 pg/mL; IQR, 55.6 to 83 pg/mL; P = 0.0024) and from before to during pegvisomant therapy (median, 97 pg/mL; IQR, 77 to 175 pg/mL vs median, 63; IQR, 61 to 109 pg/mL; P = 0.006). The plasma AgRP level correlated with GH (r = 0.319; P = 0.011) and IGF-1 (r = 0.292; P = 0.002). In repeated measure analysis, AgRP was significantly associated with IGF-1. CONCLUSIONS: Our data have provided evidence of a stimulatory effect of GH on plasma AgRP in humans. The levels were greater in active acromegaly and decreased in parallel with GH and IGF-1 decreases with acromegaly treatment. Data from mice suggest that AgRP may mediate some of the known effects of GH on energy metabolism. This warrants further study in patients with acromegaly and other populations.


Assuntos
Acromegalia/sangue , Proteína Relacionada com Agouti/sangue , Antagonistas de Hormônios/uso terapêutico , Hormônio do Crescimento Humano/análogos & derivados , Receptores da Somatotropina/antagonistas & inibidores , Acromegalia/tratamento farmacológico , Acromegalia/cirurgia , Adenoma/sangue , Adenoma/tratamento farmacológico , Adenoma/cirurgia , Adulto , Feminino , Hormônio do Crescimento Humano/sangue , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/sangue , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Neoplasias Hipofisárias/sangue , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/cirurgia , Resultado do Tratamento , Adulto Jovem
15.
J Endocr Soc ; 3(3): 590-601, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30820484

RESUMO

The hypothalamic melanocortin system composed of proopiomelanocortin (POMC) and agouti-related protein (AgRP) neurons plays a key role in maintaining energy homeostasis. The POMC-derived peptides, α-MSH and ß-EP, have distinct roles in this process. α-MSH inhibits food intake, whereas ß-EP, an endogenous opioid, can inhibit POMC neurons and stimulate food intake. A mouse model was used to examine the effects of opioid antagonism with naltrexone (NTX) on Pomc and Agrp gene expression and POMC peptide processing in the hypothalamus in conjunction with changes in energy balance. There were clear stimulatory effects of NTX on hypothalamic Pomc in mice receiving low- and high-fat diets, yet only transient decreases in food intake and body weight gain were noted. The effects on Pomc expression were accompanied by an increase in POMC prohormone levels and a decrease in levels of the processed peptides α-MSH and ß-EP. Arcuate expression of the POMC processing enzymes Pcsk1, Pcsk2, and Cpe was not altered by NTX, but expression of Prcp, an enzyme that inactivates α-MSH, increased after NTX exposure. NTX exposure also stimulated hypothalamic Agrp expression, but the effects of NTX on energy balance were not enhanced in Agrp-null mice. Despite clear stimulatory effects of NTX on Pomc expression in the hypothalamus, only modest transient decreases in food intake and body weight were seen. Effects of NTX on POMC processing, and possibly α-MSH inactivation, as well as stimulatory effects on AgRP neurons could mitigate the effects of NTX on energy balance.

16.
J Clin Endocrinol Metab ; 104(3): 961-969, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597030

RESUMO

Context: Glucocorticoids regulate energy balance, in part by stimulating the orexigenic neuropeptide agouti-related protein (AgRP). AgRP neurons express glucocorticoid receptors, and glucocorticoids have been shown to stimulate AgRP gene expression in rodents. Objective: We sought to determine whether there is a relationship between plasma AgRP and hypothalamic AgRP in rats and to evaluate the relationship between cortisol and plasma AgRP in humans. Methods: We retrospectively evaluated plasma AgRP levels prior to transsphenoidal surgery in 31 patients with Cushing disease (CD) vs 31 sex- and body mass index-matched controls from a separate study. We then prospectively measured plasma AgRP, before and 6 to 12 months after surgery, in a subgroup of 13 patients with CD. Plasma and hypothalamic AgRP were measured in adrenalectomized rats with and without corticosterone replacement. Results: Plasma AgRP was stimulated by corticosterone in rats and correlated with hypothalamic AgRP expression. Plasma AgRP levels were higher in patients with CD than in controls (139 ± 12.3 vs 54.2 ± 3.1 pg/mL; P < 0.0001). Among patients with CD, mean 24-hour urine free cortisol (UFC) levels were 257 ± 39 µg/24 hours. Strong positive correlations were observed between plasma AgRP and UFC (r = 0.76; P < 0.0001). In 11 of 13 patients demonstrating surgical cure, AgRP decreased from 126 ± 20.6 to 62.5 ± 8.0 pg/mL (P < 0.05) postoperatively, in parallel with a decline in UFC. Conclusions: Plasma AgRP levels are elevated in CD, are tightly correlated with cortisol concentrations, and decline with surgical cure. These data support the regulation of AgRP by glucocorticoids in humans. AgRP's role as a potential biomarker and as a mediator of the adverse metabolic consequences of CD deserves further study.


Assuntos
Proteína Relacionada com Agouti/sangue , Glucocorticoides/metabolismo , Hidrocortisona/sangue , Hipersecreção Hipofisária de ACTH/sangue , Adulto , Idoso , Proteína Relacionada com Agouti/metabolismo , Animais , Corticosterona/administração & dosagem , Feminino , Humanos , Hipotálamo/citologia , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Animais , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Hipersecreção Hipofisária de ACTH/patologia , Hipersecreção Hipofisária de ACTH/cirurgia , Estudos Prospectivos , Ratos , Estudos Retrospectivos , Adulto Jovem
17.
Carcinogenesis ; 40(1): 164-172, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30295739

RESUMO

RAD9A plays an important role in prostate tumorigenesis and metastasis-related phenotypes. The protein classically functions as part of the RAD9A-HUS1-RAD1 complex but can also act independently. RAD9A can selectively transactivate multiple genes, including CDKN1A and NEIL1 by binding p53-consensus sequences in or near promoters. RAD9A is overexpressed in human prostate cancer specimens and cell lines; its expression correlates with tumor progression. Silencing RAD9A in prostate cancer cells impairs their ability to form tumors in vivo and migrate as well as grow anchorage independently in vitro. We demonstrate herein that RAD9A transcriptionally controls AGR2, a gene aberrantly overexpressed in patients with metastatic prostate cancer. Transient or stable knockdown of RAD9A in PC-3 cells caused downregulation of AGR2 protein abundance. Reduced AGR2 protein levels were due to lower abundance of AGR2 mRNA. The AGR2 genomic region upstream of the coding initiation site contains several p53 consensus sequences. RAD9A bound specifically to the 5'-untranslated region of AGR2 in PC-3 cells at a partial p53 consensus sequence at position +3136 downstream from the transcription start site, determined by chromatin immunoprecipitation, followed by PCR amplification. Binding of RAD9A to the p53 consensus sequence was sufficient to drive AGR2 gene transcription, shown by a luciferase reporter assay. In contrast, when the RAD9A-binding sequence on the AGR2 was mutated, no luciferase activity was detected. Knockdown of RAD9A in PC-3 cells impaired cell migration and anchorage-independent growth. However, ectopically expressed AGR2 in RAD9A-depleted PC-3 cells restored these phenotypes. Our results suggest RAD9A drives metastasis by controlling AGR2 abundance.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Neoplasias da Próstata/patologia , Proteínas/genética , Linhagem Celular Tumoral , Movimento Celular , Humanos , Masculino , Mucoproteínas , Metástase Neoplásica , Proteínas Oncogênicas , Fenótipo , RNA Mensageiro/análise , Transcrição Gênica
18.
ACS Med Chem Lett ; 9(9): 935-940, 2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30258544

RESUMO

The X-ray structure of the previously reported PPARδ modulator 1 bound to the ligand binding domain (LBD) revealed that the amide moiety in 1 exists in the thermodynamically disfavored cis-amide orientation. Isosteric replacement of the cis-amide with five-membered heterocycles led to the identification of imidazole 17 (MA-0204), a potent, selective PPARδ modulator with good pharmacokinetic properties. MA-0204 was tested in vivo in mice and in vitro in patient-derived muscle myoblasts (from Duchenne Muscular Dystrophy (DMD) patients); 17 altered the expression of PPARδ target genes and improved fatty acid oxidation, which supports the therapeutic hypothesis for the study of MA-0204 in DMD patients.

19.
J Endocr Soc ; 1(10): 1235-1246, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29264449

RESUMO

CONTEXT: Hypothalamic proopiomelanocortin (POMC) is processed to α-melanocyte-stimulating hormone, which interacts with the melanocortin antagonist agouti-related protein (AgRP), to regulate energy balance. The POMC-derived opioid peptide ß-endorphin (ß-EP) also affects feeding behavior via interactions with brain µ-opioid receptors (MORs), including autoinhibitory interactions with MOR expressed by POMC neurons. The opioid antagonist naltrexone (NTX) stimulates POMC neurons in rodents and decreases food intake. OBJECTIVE AND DESIGN: The effect of NTX on brain POMC in humans was assessed by measuring POMC peptide concentrations in lumbar cerebrospinal fluid (CSF). AgRP and cortisol levels were also measured because both are inhibited by opioids. In a double-blinded crossover study, 14 healthy subjects were given NTX (50 mg daily) or placebo for either 2 or 7 days. RESULTS: CSF ß-EP levels increased after 2 and 7 days of NTX treatment; CSF POMC levels did not change, but the ß-EP-to-POMC ratio increased. CSF AgRP levels did not change, but plasma AgRP levels tended to increase after NTX (P = 0.06). Cortisol increased in plasma and CSF after NTX treatment; these changes correlated positively with changes in AgRP levels. CONCLUSION: Opioid antagonism stimulates POMC peptide release into CSF in humans. The increase in the CSF ß-EP-to-POMC ratio could indicate selective release of processed peptides or an effect on POMC processing. Furthermore, AgRP and cortisol stimulation by NTX may mitigate POMC-induced decrease in food intake. It remains to be determined if biomarkers in CSF and plasma could be used to predict responses to pharmacotherapy targeting the melanocortin system.

20.
Bioorg Med Chem Lett ; 27(23): 5230-5234, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29103972

RESUMO

Optimization of benzamide PPARδ modulator 1 led to (E)-6-(2-((4-(furan-2-yl)-N-methylbenzamido)methyl)phenoxy)-4-methylhex-4-enoic acid (18), a potent selective PPARδ modulator with significantly improved exposure in multiple species following oral administration.


Assuntos
Benzamidas/farmacocinética , Administração Oral , Animais , Benzamidas/administração & dosagem , Benzamidas/sangue , Relação Dose-Resposta a Droga , Humanos , Injeções Intravenosas , Macaca fascicularis , Masculino , Camundongos , Estrutura Molecular , Ratos Wistar , Relação Estrutura-Atividade
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