Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 14.432
Filtrar
1.
Gene ; 812: 146112, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-34896518

RESUMO

The Glial cell-derived neurotrophic factor (Gdnf) and testosterone induce the spermatogonial stem cells (SSCs) self-renewal and spermatogenesis, respectively. In present study the stimulating role of testosterone on Sertoli cells to produce Gdnf, and the possible effect of Gdnf on Gfrα1 and c-RET expressions were investigated. The TM4 cells (line Sertoli cells) were co-cultured with [0.1, 0.2 and 0.4 (ng/ml)] of exogenous and TM3 (line Leydig cells)-produced testosterones, and consequently the TM4-produced Gdnf concentration was evaluated. Next, the SSCs were co-cultured with the TM-4 derived media (endogenous Gdnf) and exogenous Gdnf [0.1, 0.2, and 0.4 ng/ml)]. The 0.1 and 0.2 ng/ml endogenous and 3 concentrations of exogenous testosterone up-regulated the Gdnf expression versus non-treated Sertoli cells. The TM4-produced and exogenous Gdnfs, in all concentrations, up-regulated the receptors expression. In conclusion, the testosterone, solely, stimulates the Gdnf synthesis and the Gdnf, individually, amplifies its receptor's expression at mRNA and protein levels.


Assuntos
Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Células Intersticiais do Testículo/citologia , Células de Sertoli/citologia , Testosterona/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Regulação da Expressão Gênica/efeitos dos fármacos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Testosterona/farmacologia , Regulação para Cima
2.
Arch Oral Biol ; 132: 105289, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34695671

RESUMO

OBJECTIVE: Evaluate the effects of testosterone replacement therapy (TRT) and mate tea (MT) [Ilex paraguariensis] on biochemical, functional, and redox parameters of saliva in orchiectomized rats (ORX) DESIGN: Sixty young adult male Wistar rats (3 months old) were either castrated bilaterally or underwent fictitious surgery (SHAM) and were distributed into 5 groups: SHAM, ORX, TU (castrated rats that received a single intramuscular injection of testosterone undecanoate 100 mg/kg), MT (castrated rats that received MT 20 mg/kg, via intragastric gavage, daily), and TU + MT. All treatments started 4 weeks after castration (4 months old) and lasted 4 weeks (5 months old). At the end of treatment, pilocarpine-induced salivary secretion was collected to analyze salivary flow rate (SFR) and biochemistry composition through determination of total protein (TP), amylase (AMY), electrolyte, and biomarkers of oxidative stress. RESULTS: ORX increased SFR, salivary buffering capacity, calcium, phosphate, chloride, total antioxidant capacity, thiobarbituric acid reactive substances (TBARs), and carbonyl protein, reduced TP and AMY activity, and did not change pH, sodium, and potassium compared to SHAM. TU and TU+MT restored all salivary parameters to values of SHAM, while only TBARs and AMY returned to SHAM levels in the MT group. CONCLUSIONS: TRT with long-acting TU restored the biochemical, functional, and redox parameters of saliva in orchiectomized rats. Although MT did not have a TRT-like effect on salivary gland function, the more effective reduction in lipid oxidative damage in the MT and TU + MT groups could be considered as adjuvant to alleviate the salivary oxidative stress induced by orchiectomy.


Assuntos
Ilex paraguariensis , Animais , Oxirredução , Ratos , Ratos Wistar , Saliva , Chá , Testosterona/farmacologia
3.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638962

RESUMO

Gaining detailed knowledge about sex-related immunoregulation remains a crucial prerequisite for the development of adequate disease models and therapeutic strategies enabling personalized medicine. Here, the key parameter of the production of cytokines mediating disease resolution was investigated. Among these cytokines, STAT3-activating interleukin (IL)-22 is principally associated with recovery from tissue injury. By investigating paradigmatic acetaminophen-induced liver injury, we demonstrated that IL-22 expression is enhanced in female mice. Increased female IL-22 was confirmed at a cellular level using murine splenocytes stimulated by lipopolysaccharide or αCD3/CD28 to model innate or adaptive immunoactivation. Interestingly, testosterone or dihydrotestosterone reduced IL-22 production by female but not by male splenocytes. Mechanistic studies on PMA/PHA-stimulated T-cell-lymphoma EL-4 cells verified the capability of testosterone/dihydrotestosterone to reduce IL-22 production. Moreover, we demonstrated by chromatin immunoprecipitation that testosterone impairs binding of the aryl hydrocarbon receptor to xenobiotic responsive elements within the murine IL-22 promoter. Overall, female mice undergoing acute liver injury and cultured female splenocytes upon inflammatory activation display increased IL-22. This observation is likely related to the immunosuppressive effects of androgens in males. The data presented concur with more pronounced immunological alertness demonstrable in females, which may relate to the sex-specific course of some immunological disorders.


Assuntos
Acetaminofen/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Expressão Gênica/efeitos dos fármacos , Interleucinas/genética , Interleucinas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Acetaminofen/sangue , Imunidade Adaptativa/efeitos dos fármacos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem Celular Tumoral , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/genética , Di-Hidrotestosterona/farmacologia , Modelos Animais de Doenças , Feminino , Imunidade Inata/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/imunologia , Lipopolissacarídeos/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Hidrocarboneto Arílico/metabolismo , Fatores Sexuais , Baço/citologia , Baço/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Testosterona/farmacologia
4.
J Forensic Leg Med ; 83: 102248, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34478996

RESUMO

This study investigated the biochemical and histopathological alterations along with the immunoexpression pattern of heat shock protein 27 (Hsp27) within 6 h postmortem (PM) in skeletal muscle of boldenone (BOL)-treated rats. Forty-eight male rats were divided into two groups; a control group received sesame oil (0.25 mL/kg bwt), and BOL group received 5 mg/kg bwt BOL. Both treatments were intramuscularly injected once a week for eight weeks. Rats were euthanized by cervical dislocation, and the skeletal muscle specimens were collected at zero-time, 2, 4, and 6 h PM for biochemical and histopathological evaluations. The results revealed that BOL treatment significantly increased pH, MDA, ATP, ADP, glycogen, and hydroxyproline values. Still, it decreased the GPX, GST, and lactic acid levels, and Hsp27 immunoexpression compared to the control group. With increasing postmortem interval (PMI), whether control or BOL-treated, a significant reduction in pH value, markers of muscular antioxidant status, ATP, ADP, glycogen, hydroxyproline levels, as well as Hsp27 immunoexpression but a significant increase in lipid peroxidation and lactic acid content were recorded. Of note, the interaction between BOL treatment and PMI had a significant effect on ATP, ADP, lactic acid, hydroxyproline, GST, MDA, and TAC levels. Conclusively, these findings signify BOL exposure's modifying effect on the energy content, oxidative status, and histological architecture of skeletal muscles in the early PMI that reflected in delaying the onset of rigor mortis. For forensic practitioners, these findings should be highly considered at estimating PMI in athletic, AAS-treated patients, and fattening animals.


Assuntos
Anabolizantes/farmacologia , Androgênios/farmacologia , Proteínas de Choque Térmico HSP27/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Mudanças Depois da Morte , Testosterona/análogos & derivados , Animais , Proteínas de Choque Térmico HSP27/metabolismo , Concentração de Íons de Hidrogênio , Imuno-Histoquímica , Masculino , Modelos Animais , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Rigor Mortis , Testosterona/farmacologia
5.
Molecules ; 26(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34443306

RESUMO

This study aimed to evaluate and compare the effects of co-treatment with purified annatto oil (PAO) or its granules (GRA, Chronic®) with that of testosterone on the orchiectomy-induced osteoporosis in Wistar rats. After surgery, rats were treated from day 7 until day 45 with testosterone only (TES, 7 mg/kg, IM) or TES + PAO or GRA (200 mg/kg, p.o.). The following parameters were evaluated: food/water intake, weight, HDL, LDL, glucose, triglycerides (TG), total cholesterol (TC), alkaline phosphatase levels, blood phosphorus and calcium contents, femur weight, structure (through scanning electron microscopy), and calcium content (through atomic absorption spectrophotometry). Our results show that orchiectomy could significantly change the blood lipid profile and decrease bone integrity parameters. Testosterone reposition alone could improve some endpoints, including LDL, TC, bone weight, and bone calcium concentration. However, other parameters were not significantly improved. Co-treatment with PAO or GRA improved the blood lipid profile and bone integrity more significantly and improved some endpoints not affected by testosterone reposition alone (such as TG levels and trabeculae sizes). The results suggest that co-treatment with annatto products improved the blood lipid profile and the anti-osteoporosis effects of testosterone. Overall, GRA had better results than PAO.


Assuntos
Bixaceae/química , Carotenoides/química , Fêmur/efeitos dos fármacos , Lipídeos/sangue , Orquiectomia , Osteoporose/sangue , Osteoporose/etiologia , Extratos Vegetais/química , Óleos Vegetais/farmacologia , Testosterona/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Fêmur/ultraestrutura , Masculino , Substâncias Protetoras/farmacologia , Ratos Wistar
6.
J Steroid Biochem Mol Biol ; 213: 105951, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34271023

RESUMO

The biodynamics and biokinetics of sex hormones are complex. In addition to the classical steroid receptors (nuclear receptors), these hormones act through several non-genomic mechanisms. Modulation of ABC-transporters by progesterone represents a non-genomic mechanism. In the present study, we employed inside out vesicles from human erythrocytes to characterize high affinity cGMP transport by ABCC5 (member 5 of the ATP-Binding Cassette subfamily C). Progesterone and testosterone inhibited the transport with respective Ki of 1.2 ± 0.3 and 2.0 ± 0.6 µmol/L. We used virtual ligand screening (VLS) to identify analogues to progesterone and testosterone. A large number of substances were screened in silico and the 19 most promising candidates were screened in vitro. Each substance was tested for a concentration of 10 µmol/L. The range of cGMP transport reduction was 21.5% to 86.2% for progesterone analogues and 8.6% to 93.8 % for testosterone analogues. Three of the most potent test compounds (TC) of each analogue class, in addition to progesterone and testosterone, were characterized for concentrations from 1 nanomol/L to 1 mmol/L. The progesterone analogues showed following Ki-values (µmol/L): TC-08: 0.61, TC-16: 0.66 and TC-15: 9.3. The Ki-values (µmol/L) for the testosterone analogues were: TC-18: 0.10, TC-07: 0.67 andTC-05: 2.0. The present study shows that VLS may be a versatile tool in the development of membrane transport modulating agents (MTMAs).


Assuntos
GMP Cíclico/metabolismo , Membrana Eritrocítica/efeitos dos fármacos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Progesterona/farmacologia , Testosterona/farmacologia , Transporte Biológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Membrana Eritrocítica/metabolismo , Expressão Gênica , Ensaios de Triagem em Larga Escala , Humanos , Cinética , Ligantes , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Progesterona/análogos & derivados , Ligação Proteica , Relação Estrutura-Atividade , Testosterona/análogos & derivados , Interface Usuário-Computador
7.
Mol Pharmacol ; 100(3): 224-236, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34210765

RESUMO

Mounting evidence has revealed that despite the high degree of sequence homology between cytochrome P450 3A isoforms (i.e., CYP3A4 and CYP3A5), they have the propensities to exhibit vastly different irreversible and reversible interactions with a single substrate. We have previously established that benzbromarone (BBR), a potent uricosuric agent used in the management of gout, irreversibly inhibits CYP3A4 via mechanism-based inactivation (MBI). However, it remains unelucidated if CYP3A5-its highly homologous counterpart-is susceptible to inactivation by BBR. Using three structurally distinct probe substrates, we consistently demonstrated that MBI was not elicited in CYP3A5 by BBR. Our in silico covalent docking models and molecular dynamics simulations suggested that disparities in the susceptibilities toward MBI could be attributed to the specific effects of BBR covalent adducts on the F-F' loop. Serendipitously, we also discovered that BBR reversibly activated CYP3A5-mediated rivaroxaban hydroxylation wherein apparent V max increased and K m decreased with increasing BBR concentration. Fitting data to the two-site model yielded interaction factors α and ß of 0.44 and 5.88, respectively, thereby confirming heterotropic activation of CYP3A5 by BBR. Furthermore, heteroactivation was suppressed by the CYP3A inhibitor ketoconazole in a concentration-dependent manner and decreased with increasing preincubation time, implying that activation was incited via binding of parent BBR molecule within the enzymatic active site. Finally, noncovalent docking revealed that CYP3A5 can more favorably accommodate both BBR and rivaroxaban in concert as compared with CYP3A4, which further substantiated our experimental observations. SIGNIFICANCE STATEMENT: Although it has been previously demonstrated that benzbromarone (BBR) inactivates CYP3A4, it remains uninterrogated whether it also elicits mechanism-based inactivation in CYP3A5, which shares ∼85% sequence similarity with CYP3A4. This study reported that BBR exhibited differential irreversible and reversible interactions with both CYP3A isoforms and further unraveled the molecular determinants underpinning their diverging interactions. These data offer important insight into differential kinetic behavior of CYP3A4 and CYP3A5, which potentially contributes to interindividual variabilities in drug disposition.


Assuntos
Benzobromarona/química , Inibidores do Citocromo P-450 CYP3A/química , Citocromo P-450 CYP3A/química , Benzobromarona/metabolismo , Benzobromarona/farmacologia , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/farmacologia , Humanos , Hidroxilação/efeitos dos fármacos , Hidroxilação/fisiologia , Concentração Inibidora 50 , Midazolam/metabolismo , Midazolam/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Rivaroxabana/metabolismo , Rivaroxabana/farmacologia , Testosterona/metabolismo , Testosterona/farmacologia
8.
J Clin Hypertens (Greenwich) ; 23(7): 1420-1430, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34114726

RESUMO

Testosterone replacement therapies have been shown to increase blood pressure (BP) in hypogonadal men. We studied the effects of a new formulation of testosterone undecanoate (Kyzatrex™) on ambulatory blood pressure (ABP) and heart rate, in 155 men with hypogonadism (mean age, 50.5 years, 76.8% white, 36.1% on antihypertensive therapy). The ABP, heart rate and clinical assessments were obtained at baseline and following 120 and 180 days of therapy. Mean changes from baseline in 24-h ambulatory systolic BP of 1.7 mmHg (95% CI, 0.3, 3.1) at day 120 and 1.8 mmHg (95% CI, 0.3, 3.2) at day 180 were observed post-treatment. For those men on antihypertensive drug therapy, increases in mean 24-h systolic BP were greater than those not taking antihypertensive drugs (3.4 vs 0.7 mmHg at day 120 and 3.1 vs 1.0 mmHg at day 180, respectively). Changes from baseline in 24-h diastolic BP and heart rate at day 120 were smaller (<1 mmHg and <1 beat/min, respectively). There were no relationships observed between testosterone concentration or hemoglobin levels with ABP. Multivariable analyses showed that baseline ambulatory BP and antihypertensive therapy were significantly correlated with BP changes. These data demonstrate small increases in ambulatory BP following 120 days on this oral testosterone undecanoate with no further changes at 180 days. Changes in ambulatory BP were minimal in patients not taking antihypertensive therapy.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Hipertensão , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Testosterona/análogos & derivados , Testosterona/farmacologia
9.
Aging (Albany NY) ; 13(12): 16229-16247, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34139672

RESUMO

Brain mitochondrial dysfunction and reduced testosterone levels are common features of aging in men. Although evidence suggests that the two phenomena are interrelated, it is unclear whether testosterone supplementation ameliorates mitochondrial dysfunction in the aging male brain. Here, we show that testosterone supplementation significantly alleviates exploratory behavioral deficits and oxidative damage in the substantia nigra and hippocampus of aging male rats. These effects were consistent with improved mitochondrial function, reflected by testosterone-induced increases in mitochondrial membrane potential (MMP), antioxidant enzyme (GSH-PX, catalase, and Mn-SOD) expression/activity, and mitochondrial respiratory complex activities in both brain regions. Furthermore, elevated PGC-1α, NRF-1, and TFAM expression (suggestive of enhanced mitochondrial biogenesis), increased citrate synthase activity, mtDNA copy number, and ND1, COX1, and ATP6 expression (indicative of increased mitochondrial content), as well as increased PINK1/Parkin and decreased P62 expression (suggesting mitophagy activation), were detected in the substantial nigra and hippocampus of aged male rats after testosterone supplementation. These findings suggest that testosterone supplementation may be a viable approach to ameliorating brain mitochondrial dysfunction and thus prevent or treat cognitive-behavioral deficits and neurodegenerative conditions associated with aging.


Assuntos
Envelhecimento/patologia , Encéfalo/metabolismo , Mitocôndrias/patologia , Testosterona/farmacologia , Envelhecimento/sangue , Animais , Antioxidantes/farmacologia , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Proteínas Quinases/metabolismo , Ratos Sprague-Dawley , Substância Negra/metabolismo , Testosterona/sangue , Tirosina 3-Mono-Oxigenase/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
10.
J Steroid Biochem Mol Biol ; 212: 105927, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34089835

RESUMO

The human microsomal cytochrome P450 enzyme CYP46A1 plays a crucial role in cholesterol elimination from the brain. It performs a 24-hydroxylation of cholesterol and is of outstanding significance for memory and cognition. This study demonstrates the catalytic activity of human CYP46A1 towards an anabolic androgenic steroid, oral turinabol (dehydrochloromethyltestosterone, 4-chloro-17ß-dihydroxy,17α-methylandrosta-1,4-dien-3-one), which is a doping substance. CYP46A1 is the first human microsomal steroid-converting P450 showing activity towards this xenobiotic compound. Furthermore, the inhibitory effect of oral turinabol on the cholesterol conversion has been investigated in vitro demonstrating competition of the two substrates on the active site of CYP46A1 which might be of importance for potential pathogenic effects of oral turinabol. The conversion of oral turinabol was found to be selective resulting in the formation of only one product, as shown by HPLC analysis. To produce sufficient amounts of this product for NMR analysis, a system expressing human full-length CYP46A1 and CPR on a bicistronic vector was successfully developed realizing the selective cholesterol 24-hydroxylation in E. coli in mg amounts. Using this novel whole-cell system, the conversion of oral turinabol was performed and the product of this conversion by CYP46A1 was isolated and identified as 16ß-hydroxy oral turinabol by NMR.


Assuntos
Anabolizantes/farmacologia , Colesterol 24-Hidroxilase/metabolismo , Testosterona/análogos & derivados , Encéfalo/enzimologia , Colesterol 24-Hidroxilase/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Humanos , Simulação de Acoplamento Molecular , Oxandrolona/farmacologia , Testosterona/farmacologia
11.
Andrologia ; 53(9): e14153, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34138481

RESUMO

Sex-specific differences in brain plasticity appear to be organised by testosterone, which is particularly important during the early stages of development. The main purpose of the present study was to examine the sex differences in mRNA and protein levels of selected cell-adhesion molecules and scaffolding proteins on postnatal days 5 (P5) and 9 (P9) in the rat hippocampus, as well as evaluate the effects of testosterone treatment (100 nM, 48 hr) on synaptic proteins in SH-SY5Y (neuron-like) and U-87MG (astrocyte-like) cells. The gene expression levels of Neuroligin 3 and 'SH3 and multiple ankyrin repeat domains protein' 1 and 3 (SHANK1 and SHANK3) were significantly lower in males compared to females at P5. At P9, a similar significant trend towards a decrease in mRNA expression and protein levels of SHANK3 was found in males. Testosterone treatment induced a significant decrease of Neuroligin 1-3 mRNA expression in both SH-SY5Y and U-87MG cells. SHANK1 and SHANK3 mRNA levels significantly decreased in U-87MG cells response to testosterone presence. The presented results demonstrate that the association of selected postsynaptic cell-adhesion molecules and scaffolding proteins is sex-related. Testosterone appears to be particularly involved in the developmental mechanisms related to neuroplasticity.


Assuntos
Hipocampo , Testosterona , Animais , Feminino , Expressão Gênica , Masculino , Neurônios , RNA Mensageiro/genética , Ratos , Testosterona/farmacologia
12.
Integr Comp Biol ; 61(1): 269-282, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-33974077

RESUMO

In seasonally breeding vertebrates, hormones coordinate changes in nervous system structure and function to facilitate reproductive readiness and success. Steroid hormones often exert their effects indirectly via regulation of neuromodulators, which in turn can coordinate the modulation of sensory input with appropriate motor output. Female plainfin midshipman fish (Porichthys notatus) undergo increased peripheral auditory sensitivity in time for the summer breeding season, improving their ability to detect mates, which is regulated by steroid hormones. Reproductive females also show differences in catecholaminergic innervation of auditory circuitry compared with winter, non-reproductive females as measured by tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholaminergic synthesis. Importantly, catecholaminergic input to the inner ear from a dopaminergic-specific forebrain nucleus is decreased in the summer and dopamine inhibits the sensitivity of the inner ear, suggesting that gonadal steroids may alter auditory sensitivity by regulating dopamine innervation. In this study, we gonadectomized non-reproductive females, implanted them with estradiol (E2) or testosterone (T), and measured TH immunoreactive (TH-ir) fibers in auditory nuclei where catecholaminergic innervation was previously shown to be seasonally plastic. We found that treatment with T, but not E2, reduced TH-ir innervation in the auditory hindbrain. T-treatment also reduced TH-ir fibers in the forebrain dopaminergic cell group that projects to the inner ear, and likely to the auditory hindbrain. Higher T plasma in the treatment group was correlated with reduced-ir TH terminals in the inner ear. These T-treatment induced changes in TH-ir fibers mimic the seasonal downregulation of dopamine in the midshipman inner ear and provide evidence that steroid hormone regulation of peripheral auditory sensitivity is mediated, in part, by dopamine.


Assuntos
Batracoidiformes , Dopamina , Orelha Interna/inervação , Rombencéfalo/fisiologia , Estações do Ano , Testosterona/farmacologia , Animais , Batracoidiformes/fisiologia , Regulação para Baixo , Orelha Interna/efeitos dos fármacos , Feminino
13.
J Clin Endocrinol Metab ; 106(8): 2252-2263, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-33982080

RESUMO

OBJECTIVE: Adipose tissue distribution and glucose metabolism differ between men and women. Few studies have investigated sex differences in adipose tissue insulin resistance (adipose-IR). Herein, we investigated sex differences in adipose-IR in adults ranging from overweight to obese and the potential factors associated with sex differences in adipose-IR. METHODS: A total of 424 adults had their body mass index (BMI), adipose-IR, and sex hormones evaluated. Based on BMI, males and females were assigned to 4 groups. RESULTS: In total, males (n = 156) had higher adipose-IR than females with similar BMI levels (n = 268) (P < 0.05). Adipose-IR progressively increased from overweight to class III obesity in both males and females (all P < 0.0001); however, only in the class III obesity group was the adipose-IR significantly higher in males than in females (P = 0.025). There were significant differences in testosterone between males and females (all P < 0.01); testosterone levels were negatively correlated with adipose-IR (r = -0.333, P < 0.001) in males but positively correlated with adipose-IR (r = 0.216, P < 0.001) in females. For the logistic regression analysis, testosterone was an independent protective factor against adipose-IR in males, with an odds ratio of 0.858 (B = -0.153 [95% CI, 0.743-0.991], P = 0.037). CONCLUSIONS: Adipose-IR reflects the progressive deterioration in adipose tissue insulin sensitivity from overweight to obesity in both males and females. Males with class III obesity have more severe adipose-IR than similarly obese females. The sex difference is associated with testosterone, and low testosterone levels may contribute to more severe adipose-IR in obese males.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Resistência à Insulina/fisiologia , Obesidade/metabolismo , Sobrepeso/metabolismo , Caracteres Sexuais , Testosterona/farmacologia , Tecido Adiposo/metabolismo , Adulto , Glicemia , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Insulina/sangue , Leptina/sangue , Masculino
14.
Clin Adv Hematol Oncol ; 19(4): 228-240, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33989272

RESUMO

The androgen signaling axis has been the main therapeutic target in the management of advanced prostate cancer for several decades. Over the past years, significant advances have been made in terms of a better understanding the androgen receptor (AR) pathway and mechanisms of castration resistance, along with the development of more potent AR-targeted therapies. New drugs, such as abiraterone, enzalutamide, apalutamide, and darolutamide, have been approved for castration-resistant prostate cancer and also have demonstrated an overall survival benefit in the castration-sensitive state. Despite these major advances, the majority of patients eventually present with disease progression and a rise in prostate-specific antigen, reflecting a continuous dependence of disease on the AR pathway. In this setting, a number of AR-related mechanisms of resistance have been described, and novel strategies to overcome them are an important unmet need. In this manuscript, we review the most promising strategies to target the AR pathway in prostate cancer, including bromodomain and extraterminal (BET)/bromodomain inhibitors, CREB-binding protein/p300 inhibitors, N-terminal domain inhibitors, proteolysis-targeting chimeras, and AR-targeting vaccines. Another interesting and disruptive approach to targeting the AR and potentially reversing resistance to second-generation AR antagonists is the cyclic administration of high-dose testosterone, known as bipolar androgen therapy, which is currently being explored in multiple ongoing trials.


Assuntos
Antagonistas de Receptores de Andrógenos/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Antagonistas de Receptores de Andrógenos/farmacologia , Animais , Antineoplásicos/farmacologia , Humanos , Masculino , Terapia de Alvo Molecular/métodos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Testosterona/farmacologia , Testosterona/uso terapêutico
15.
PLoS One ; 16(5): e0251864, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33999955

RESUMO

Testosterone and alendronate have been identified as two bone healing compounds which, when combined, synergistically stimulate bone regeneration. This study describes the development of a novel ultrasonic spray coating for sustained release of ancillary amounts of testosterone and alendronate encapsulated in PLGA 5004A as a carrier. Due to the low amounts of testosterone and alendronate used, sensitive in vitro assays were developed to determine in vitro release. The ultrasonic spray coating technology was optimized for coating titanium screws and pericardial collagen membranes, with the aim to improve osseo-integration and (guided) bone regeneration, respectively, without interfering with their primary mode of action. In vitro release analysis of collagen membranes and screws showed up to 21 days sustained release of the compounds without a burst release. Subsequent preclinical studies in rat and rabbit models indicated that testosterone and alendronate coated membranes and screws significantly improved bone regeneration in vivo. Coated membranes significantly improved the formation of new bone in a critical size calvarial defect model in rats (by 160% compared to controls). Coated screws implanted in rabbit femoral condyles significantly improved bone implant contact (69% vs 54% in controls), bone mineral density (121%) and bone volume (119%) up to 1.3 mm from the implant. Based on the results obtained, we suggest that implants or membranes enabled with local sustained delivery of ancillary amounts of testosterone and alendronate can be a promising system to stimulate local bone regeneration resulting in improved osseo-integration of implants and improved healing of bone defects and fractures.


Assuntos
Alendronato/farmacologia , Regeneração Óssea/efeitos dos fármacos , Osseointegração/efeitos dos fármacos , Testosterona/farmacologia , Animais , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/química , Conservadores da Densidade Óssea/farmacologia , Regeneração Óssea/fisiologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Preparações de Ação Retardada/farmacologia , Modelos Animais de Doenças , Fêmur/crescimento & desenvolvimento , Fêmur/cirurgia , Humanos , Masculino , Osseointegração/fisiologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Próteses e Implantes , Coelhos , Ratos , Titânio/química , Titânio/uso terapêutico
16.
J Postgrad Med ; 67(2): 67-74, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33942770

RESUMO

Aims: To evaluate the prevalence of metabolic syndrome (MS) and whole-body composition in patients with congenital hypogonadism and investigate the effects of replacement therapy with testosterone undecanoate on MS, insulin resistance (IR), and whole-body composition in subset of patients. Methods: In a single arm prospective longitudinal intervention study, 33 patients with congenital hypogonadism, ages 20-39 years, were recruited and their parameters of MS, whole-body composition by DXA were compared with age and BMI matched healthy controls. In 21 patients, after 9 months we prospectively studied the effect (pre-post difference) of injection testosterone undecanoate (1,000 mg) replacement on MS, IR, and whole-body compositions. Results: The prevalence of MS was similar in patients and controls (27.3% vs. 9.1%, P = 0.05). Hypogonadism patients had higher prevalence of hypertension (33% vs. 3%, P < 0.01). Patients had decrease in lean body mass (P < 0.05) as compared to controls. After testosterone replacement, there was significant decrease in waist circumference (88.6 ± 13.1 cm vs. 83.9 ± 12.9 cm, P < 0.01), truncal fat (25.9 ± 7.3% vs. 24.0 ± 6.3%, P < 0.05), fasting C-peptide (2.1 ± 0.79 ng/ml vs. 0.68 ± 0.23 ng/ml, P < 0.01), serum proinsulin [1.43 (0.32-13.4) vs. 0.5 (0.5-3.2) pmol/l, P < 0.001] and a significant increase in lean body mass (46,906 ± 8,876 gm vs. 50,083 ± 7,590 gm, P < 0.001). Homeostasis model assessment of insulin resistance (HOMA-IR) (4.6 ± 1.7 vs. 0.5 ± 0.2, P < 0.001) and homeostatic model for assessment of insulin sensitivity (HOMA%S) [21 (12-65) vs. 206 (125-714), P < 0.001] were improved significantly following testosterone replacement. Conclusion: In this study, 36 weeks of testosterone replacement resulted in significant decrease in waist circumference, IR, truncal fat, total body fat and improvement in lean body mass, and insulin sensitivity.


Assuntos
Terapia de Reposição Hormonal , Hipogonadismo/tratamento farmacológico , Testosterona/uso terapêutico , Adulto , Índice de Massa Corporal , Seguimentos , Humanos , Hipogonadismo/congênito , Hipogonadismo/fisiopatologia , Resistência à Insulina , Estudos Longitudinais , Masculino , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Estudos Prospectivos , Testosterona/farmacologia , Adulto Jovem
17.
Eur J Med Chem ; 220: 113496, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-33933755

RESUMO

The synthesis of two isomeric testosterone dimers and an androstenedione dimer is reported. The design takes advantage of an efficient transformation of testosterone leading to the synthesis of the key diene, 7α-(buta-1,3-dienyl)-4-androsten-17ß-ol-3-one, through an elimination reaction. It was found that in some instances the same reaction led to partial epimerization of the 17ß-hydroxyl group into the 17α-hydroxyl group. The specific orientation of the hydroxyl function was confirmed by NMR spectroscopy. Capitalizing on this unforeseen side reaction, several dimers were assembled using an olefin metathesis reaction with Hoveyda-Grubbs catalyst. This led to the formation of two isomeric testosterone dimers with 17α-OH or 17ß-OH (14α and 14ß) as well as an androstenedione dimer (14). The new dimers and their respective precursors were tested on androgen-dependent (LNCaP) and androgen independent (PC3 and DU145) prostate cancer cells. It was discovered that the most active dimer was made of the natural hormone testosterone (14ß) with an average IC50 of 13.3 µM. In LNCaP cells, 14ß was ∼5 times more active than the antiandrogen drug cyproterone acetate (IC50 of 12.0 µM vs. 59.6 µM, respectively). At low concentrations (0.25-0.5 µM), 14α and 14ß were able to completely inhibit LNCaP cell growth induced by testosterone or dihydrotestosterone. Furthermore, cross-reactivity of androgen-based dimers with sterol-metabolizing cytochrome P450 3A4 was explored and the results are disclosed herein.


Assuntos
Androstenodiona/farmacologia , Antineoplásicos/farmacologia , Citocromo P-450 CYP3A/metabolismo , Desenho de Fármacos , Neoplasias da Próstata/tratamento farmacológico , Testosterona/farmacologia , Androstenodiona/síntese química , Androstenodiona/química , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dimerização , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Estrutura Molecular , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Recombinantes , Relação Estrutura-Atividade , Testosterona/síntese química , Testosterona/química , Células Tumorais Cultivadas
18.
Sci Rep ; 11(1): 9621, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953236

RESUMO

Glucocorticoids (GCs) are rapidly released in response to stress and play an important role in the physiological adjustments to re-establish homeostasis. The mode of action of GCs for stress coping is mediated largely by the steroid binding to the glucocorticoid receptor (GR), a ligand-bound transcription factor, and modulating the expression of target genes. However, GCs also exert rapid actions that are independent of transcriptional regulation by modulating second messenger signaling. However, a membrane-specific protein that transduces rapid GCs signal is yet to be characterized. Here, using freshly isolated hepatocytes from rainbow trout (Oncorhynchus mykiss) and fura2 fluorescence microscopy, we report that stressed levels of cortisol rapidly stimulate the rise in cytosolic free calcium ([Ca2+]i). Pharmacological manipulations using specific extra- and intra-cellular calcium chelators, plasma membrane and endoplasmic reticulum channel blockers and receptors, indicated extracellular Ca2+ entry is required for the cortisol-mediated rise in ([Ca2+]i). Particularly, the calcium release-activated calcium (CRAC) channel gating appears to be a key target for the rapid action of cortisol in the ([Ca2+]i) rise in trout hepatocytes. To test this further, we carried out in silico molecular docking studies using the Drosophila CRAC channel modulator 1 (ORAI1) protein, the pore forming subunit of CRAC channel that is highly conserved. The result predicts a putative binding site on CRAC for cortisol to modulate channel gating, suggesting a direct, as well as an indirect regulation (by other membrane receptors) of CRAC channel gating by cortisol. Altogether, CRAC channel may be a novel cortisol-gated Ca2+ channel transducing rapid nongenomic signalling in hepatocytes during acute stress.


Assuntos
Canais de Cálcio Ativados pela Liberação de Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Hepatócitos/efeitos dos fármacos , Hidrocortisona/farmacologia , Ativação do Canal Iônico/efeitos dos fármacos , Animais , Corticosterona/farmacologia , Inibidores Enzimáticos/farmacologia , Estradiol/farmacologia , Hepatócitos/metabolismo , Oncorhynchus mykiss , Testosterona/farmacologia , Tapsigargina/farmacologia
19.
Life Sci ; 278: 119570, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33964295

RESUMO

AIMS: Increasing evidence has shown that hormone secretion is regulated by endocytosis. Eps15 homology domain-containing protein 3 (EHD3) is an endocytic-trafficking regulatory protein, but whether EHD3 is associated with testosterone secretion is not clear. This work aims to explore the role of EHD3 in testosterone synthesis. MAIN METHODS: Testosterone concentration was determined by ELISA. The effects of EHD3 on endocytosis were assessed by exosomes tracing assay and Immunofluorescence. Targeting relationship between EHD3 and NR5A1 was verified by chromatin immunoprecipitation (ChIP) and dual luciferase reporter gene assay in Leydig cells. For in vivo assessments, conditional NR5A1 knockout mouse model was established with CRISPR/Cas9 gene targeting technology. KEY FINDINGS: EHD3 overexpression significantly increased the concentration of testosterone. EHD3 knockdown markedly decreased testosterone synthesis by reducing endocytosis. The activity of the EHD3 promoter was positively regulated by NR5A1, which occupied the conserved sequence "AGGTCA" in the EHD3 promoter. Furthermore, mice with a Leydig cell-specific conditional NR5A1 knockout displayed the blunted levels of EHD3 and clathrin (a key factor for endocytosis), and serum testosterone concentration compared with NR5A1f/f mice. SIGNIFICANCE: This study suggests a potential molecular mechanism of testosterone synthesis to fully understand male reproductive health.


Assuntos
Proteínas de Transporte/metabolismo , Endocitose , Exossomos/metabolismo , Regulação da Expressão Gênica , Fator Esteroidogênico 1/metabolismo , Testosterona/metabolismo , Animais , Sistemas CRISPR-Cas , Proteínas de Transporte/genética , Imunoprecipitação da Cromatina , Feminino , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasmídeos/metabolismo , Regiões Promotoras Genéticas , RNA Interferente Pequeno/metabolismo , Fator Esteroidogênico 1/genética , Testosterona/farmacologia
20.
Biol Pharm Bull ; 44(4): 501-506, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33790101

RESUMO

Multidrug and toxic compound extrusion (MATE) transporters are primarily expressed in the kidneys and liver, where they contribute to the excretion of organic cations. Our previous study suggested that pig MATE2 (class III) participates in testosterone secretion from Leydig cells. In humans, it is unclear which MATE class is involved in testosterone transport. In this study, we aimed to clarify whether human MATE1 (hMATE1) or human MATE2K (hMATE2K) mediates testosterone transport. To confirm that testosterone inhibits transporter-mediated tetraethylammonium (TEA) uptake, a cis-inhibition assay was performed using cells that stably expressed hMATE1 or hMATE2K. Docking simulations were performed to characterize differences in the binding of hMATE1 and hMATE2K to testosterone. Transport experiments in LLC-PK1 cells that stably expressed hMATE1 were used to test whether hMATE1 mediates testosterone transport. We detected differences between the amino acid sequences of the substrate-binding sites of hMATE1 and hMATE2K that could potentially be involved in testosterone binding. Testosterone and estradiol inhibited TEA uptake mediated by hMATE1 but not that mediated by hMATE2K. Transport experiments in LLC-PK1 cells indicated that testosterone might be transported via hMATE1. This study suggested that hMATE1, but not hMATE2K, is involved in human testosterone transport.


Assuntos
Proteínas de Transporte de Cátions Orgânicos/metabolismo , Testosterona/farmacologia , Animais , Cimetidina/farmacologia , Estradiol/farmacologia , Células HEK293 , Humanos , Células LLC-PK1 , Modelos Moleculares , Proteínas de Transporte de Cátions Orgânicos/química , Suínos , Tetraetilamônio/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...