Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 307
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Front Neuroendocrinol ; 71: 101085, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37543184

RESUMO

Substance use disorder (SUD) is a chronic condition characterized by pathological drug-taking and seeking behaviors. Remarkably different between males and females, suggesting that drug addiction is a sexually differentiated disorder. The neurobiological bases of sex differences in SUD include sex-specific reward system activation, influenced by interactions between gonadal hormone level changes, dopaminergic reward circuits, and epigenetic modifications of key reward system genes. This systematic review, adhering to PICOS and PRISMA-P 2015 guidelines, highlights the sex-dependent roles of estrogens, progesterone, and testosterone in SUD. In particular, estradiol elevates and progesterone reduces dopaminergic activity in SUD females, whilst testosterone and progesterone augment SUD behavior in males. Finally, SUD is associated with a sex-specific increase in the rate of opioid and monoaminergic gene methylation. The study reveals the need for detailed research on gonadal hormone levels, dopaminergic or reward system activity, and epigenetic landscapes in both sexes for efficient SUD therapy development.


Assuntos
Progesterona , Transtornos Relacionados ao Uso de Substâncias , Feminino , Humanos , Masculino , Dopamina/fisiologia , Epigênese Genética , Hormônios Esteroides Gonadais , Metanálise como Assunto , Caracteres Sexuais , Transtornos Relacionados ao Uso de Substâncias/genética , Revisões Sistemáticas como Assunto , Testosterona
2.
Front Neuroendocrinol ; 71: 101102, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37689249

RESUMO

The brain synthesizes a variety of neurosteroids, including neuroestradiol. Inhibition of neuroestradiol synthesis results in alterations in basic neurodevelopmental processes, such as neurogenesis, neuroblast migration, neuritogenesis and synaptogenesis. Although the neurodevelopmental actions of neuroestradiol are exerted in both sexes, some of them are sex-specific, such as the well characterized effects of neuroestradiol derived from the metabolism of testicular testosterone during critical periods of male brain development. In addition, recent findings have shown sex-specific actions of neuroestradiol on neuroblast migration, neuritic growth and synaptogenesis in females. Among other factors, the epigenetic regulation exerted by X linked genes, such as Kdm6a/Utx, may determine sex-specific actions of neuroestradiol in the female brain. This review evidences the impact of neuroestradiol on brain formation in both sexes and highlights the interaction of neural steriodogenesis, hormones and sex chromosomes in sex-specific brain development.


Assuntos
Epigênese Genética , Neuroesteroides , Feminino , Masculino , Humanos , Neurônios/metabolismo , Neuroesteroides/metabolismo , Testosterona/metabolismo
3.
J Gen Intern Med ; 38(6): 1493-1500, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36451010

RESUMO

BACKGROUND: Simultaneous cannabis/alcohol use, using both substances within a short time interval so that their effects overlap, has a greater risk of potential negative consequences than single-substance use and is more common in younger age. Relationships between recreational cannabis laws (RCLs) and changes in simultaneous cannabis/alcohol use prevalence remain untested. OBJECTIVE: To examine trends in simultaneous cannabis/alcohol use from 2008 to 2019, and investigate associations between implementation of RCLs (i.e., presence of active legal dispensaries or legal home cultivation) and simultaneous cannabis/alcohol use in the United States (U.S.). DESIGN: Repeated cross-sectional samples from the 2008-2019 U.S. National Survey on Drug Use and Health (NSDUH). PARTICIPANTS: Respondents (51% female) aged 12 and older. INTERVENTIONS: Changes in simultaneous cannabis/alcohol use before and after RCL implementation (controlling for medical cannabis law implementation) were compared in different age groups (12-20, 21-30, 31-40, 41-50, 51+), using adjusted multi-level logistic regression with state random intercepts and an RCL/age group interaction. MEASUREMENTS: Self-reported simultaneous cannabis/alcohol use. RESULTS: From 2008 to 2019, the overall prevalence of simultaneous cannabis/alcohol use declined among those aged 12-20 but increased in adults aged 21+. Model-based simultaneous cannabis/alcohol use prevalence increased after RCL implementation among respondents aged 21-30 years (+1.2%; aOR= 1.15 [95%CI = 1.04-1.27]), 31-40 years (+1.0; 1.15 [1.04-1.27]), and 41-50 years (+1.75; 1.63 [1.34-1.98]), but not in individuals aged <21 or 51+ years. CONCLUSIONS: Implementation of recreational cannabis policies resulted in increased simultaneous use of cannabis and alcohol, supporting the complementarity hypothesis, but only among adults aged 21+. Efforts to minimize harms related to simultaneous cannabis/alcohol use are critical, especially in states with RCLs. Future studies should investigate cultural norms, perceived harm, and motives related to simultaneous use.


Assuntos
Cannabis , Maconha Medicinal , Adulto , Estados Unidos/epidemiologia , Humanos , Feminino , Masculino , Prevalência , Estudos Transversais , Legislação de Medicamentos
4.
J Chem Phys ; 158(2): 024108, 2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36641386

RESUMO

The random phase approximation of time-dependent auxiliary density functional theory (TDADFT) is rederived from auxiliary density perturbation theory. Our exhaustive validation of TDADFT reveals an upshift of the excitation energies by ∼0.1 eV with respect to standard time-dependent density functional theory. For the computationally efficient implementation of TDADFT, floating point operation optimized three-center electron repulsion integral recurrence relations and their double asymptotic expansions are implemented into the Davidson solver. The computational efficiency of TDADFT is benchmarked with four sets of molecules comprising alkanes, fullerenes, DNA fragments, and zeolites. The results show that TDADFT has a computational scaling between 1.3 and 1.9 with respect to the number of basis functions, which is lower than the scaling of standard time-dependent density functional theory. Due to its computational simplifications, TDADFT is particularly well suited for Born-Oppenheimer molecular dynamics simulations. As illustrative examples, we present the temperature effects on the gas-phase absorption spectra of benzene, naphthalene, and anthracene.


Assuntos
Simulação de Dinâmica Molecular , Teoria Quântica , Teoria da Densidade Funcional , Elétrons , Alcanos
5.
Eur J Clin Invest ; 52(9): e13798, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35467758

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal and rapidly progressing neurodegenerative disease that affects motor neurons. This disease is associated with oxidative stress especially in mutant superoxide dismutase 1 (mutSOD1) patients. However, less is known for the most prevalent sporadic ALS form, due to a lack of disease models. Here, we studied oxidative stress profiles in lymphoblasts from ALS patients with mutSOD1 or unknown (undSOD1) mutations. METHODS: mutSOD1 and undSOD1 lymphoblasts, as well as sex/age-matched controls (3/group) were obtained from Coriell and divided into 46 years-old-men (C1), 46 years-old-women (C2) or 26/27 years-old-men (C3) cohorts. Growth curves were performed, and several parameters associated with redox homeostasis were evaluated, including SOD activity and expression, general oxidative stress levels, lipid peroxidation, response to oxidative stimulus, glutathione redox cycle, catalase expression, and activity, and Nrf2 transcripts. Pooled (all cohorts) and paired (intra-cohort) statistical analyses were performed, followed by clustering and principal component analyses (PCA). RESULTS: Although a high heterogeneity among lymphoblast redox profiles was found between cohorts, clustering analysis based on 7 parameters with high chi-square ranking (total SOD activity, oxidative stress levels, catalase transcripts, SOD1 protein levels, metabolic response to mM concentrations of tert-butyl hydroperoxide, glutathione reductase activity, and Nrf2 transcript levels) provided a perfect cluster segregation between samples from healthy controls and ALS (undSOD1 and mutSOD1), also visualized in the PCA. CONCLUSIONS: Our results show distinct redox signatures in lymphoblasts from mutSOD1, undSOD1 and healthy controls that can be used as therapeutic targets for ALS drug development.


Assuntos
Esclerose Lateral Amiotrófica , Superóxido Dismutase-1 , Adulto , Esclerose Lateral Amiotrófica/genética , Catalase/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Fator 2 Relacionado a NF-E2/genética , Oxirredução , Superóxido Dismutase-1/genética
6.
Cell Mol Life Sci ; 78(21-22): 7043-7060, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34633482

RESUMO

Several X-linked genes are involved in neuronal differentiation and may contribute to the generation of sex dimorphisms in the brain. Previous results showed that XX hypothalamic neurons grow faster, have longer axons, and exhibit higher expression of the neuritogenic gene neurogenin 3 (Ngn3) than XY before perinatal masculinization. Here we evaluated the participation of candidate X-linked genes in the development of these sex differences, focusing mainly on Kdm6a, a gene encoding for an H3K27 demethylase with functions controlling gene expression genome-wide. We established hypothalamic neuronal cultures from wild-type or transgenic Four Core Genotypes mice, a model that allows evaluating the effect of sex chromosomes independently of gonadal type. X-linked genes Kdm6a, Eif2s3x and Ddx3x showed higher expression in XX compared to XY neurons, regardless of gonadal sex. Moreover, Kdm6a expression pattern with higher mRNA levels in XX than XY did not change with age at E14, P0, and P60 in hypothalamus or under 17ß-estradiol treatment in culture. Kdm6a pharmacological blockade by GSK-J4 reduced axonal length only in female neurons and decreased the expression of neuritogenic genes Neurod1, Neurod2 and Cdk5r1 in both sexes equally, while a sex-specific effect was observed in Ngn3. Finally, Kdm6a downregulation using siRNA reduced axonal length and Ngn3 expression only in female neurons, abolishing the sex differences observed in control conditions. Altogether, these results point to Kdm6a as a key mediator of the higher axogenesis and Ngn3 expression observed in XX neurons before the critical period of brain masculinization.


Assuntos
Genes Ligados ao Cromossomo X/genética , Histona Desmetilases/genética , Histonas/genética , Hipotálamo/fisiologia , Neurônios/fisiologia , Diferenciação Sexual/genética , Animais , Axônios/fisiologia , Feminino , Masculino , Camundongos , Proteínas do Tecido Nervoso/genética , Caracteres Sexuais
7.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36499081

RESUMO

The existence of sex differences in disease incidence is attributed, in part, to sex differences in metabolism. Uncovering the precise mechanism driving these differences is an extraordinarily complex process influenced by genetics, endogenous hormones, sex-specific lifetime events, individual differences and external environmental/social factors. In fact, such differences may be subtle, but across a life span, increase susceptibility to a pathology. Whilst research persists in the hope of discovering an elegant biological mechanism to underpin sex differences in disease, here, we show, for the first time, that such a mechanism may be subtle in nature but influenced by multiple sex-specific factors. A proteomic dataset was generated from a gonadectomized mouse model treated with Tibolone, a menopausal hormone therapy. Following functional enrichment analysis, we identified that Alzheimer's disease and the electron transport chain-associated pathways were regulated by sex-hormone interactions. Specifically, we identified that the expression of three respirasome proteins, NDUFA2, NDUFA7 and UQCR10, is significantly altered by compounding factors that contribute to sex differences. These proteins function in bioenergetics and produce reactive oxygen species, which are each dysregulated in many diseases with sex differences in incidence. We show sex-specific reprogrammed responses to Tibolone following gonadectomy, which primarily influence the expression of proteins contributing to metabolic pathways. This further infers that metabolic differences may underpin the observed sex differences in disease, but also that hormone therapy research now has potential in exploring sex-specific interventions to produce an effective method of prevention or treatment.


Assuntos
Membranas Mitocondriais , Proteômica , Animais , Camundongos , Feminino , Masculino , Membranas Mitocondriais/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Encéfalo/metabolismo , Proteínas/metabolismo , Hormônios/metabolismo
8.
Int J Mol Sci ; 23(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36293143

RESUMO

For many decades to date, neuroendocrinologists have delved into the key contribution of gonadal hormones to the generation of sex differences in the developing brain and the expression of sex-specific physiological and behavioral phenotypes in adulthood. However, it was not until recent years that the role of sex chromosomes in the matter started to be seriously explored and unveiled beyond gonadal determination. Now we know that the divergent evolutionary process suffered by X and Y chromosomes has determined that they now encode mostly dissimilar genetic information and are subject to different epigenetic regulations, characteristics that together contribute to generate sex differences between XX and XY cells/individuals from the zygote throughout life. Here we will review and discuss relevant data showing how particular X- and Y-linked genes and epigenetic mechanisms controlling their expression and inheritance are involved, along with or independently of gonadal hormones, in the generation of sex differences in the brain.


Assuntos
Diferenciação Sexual , Cromossomo Y , Feminino , Masculino , Animais , Diferenciação Sexual/genética , Cromossomos Sexuais/genética , Cromossomos Sexuais/metabolismo , Caracteres Sexuais , Hormônios Gonadais/metabolismo , Encéfalo/metabolismo , Epigênese Genética , Cromossomo X
9.
Neurobiol Dis ; 159: 105495, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34478848

RESUMO

Long-term high-fat diet (HFD) consumption commonly leads to obesity, a major health concern of western societies and a risk factor for Alzheimer's disease (AD). Both conditions present glial activation and inflammation and show sex differences in their incidence, clinical manifestation, and disease course. HFD intake has an important impact on gut microbiota, the bacteria present in the gut, and microbiota dysbiosis is associated with inflammation and certain mental disorders such as anxiety. In this study, we have analyzed the effects of a prolonged (18 weeks, starting at 7 months of age) HFD on male and female mice, both wild type (WT) and TgAPP mice, a model for AD, investigating the behavioral profile, gut microbiota composition and inflammatory/phagocytosis-related gene expression in hippocampus. In the open-field test, no overt differences in motor activity were observed between male and female or WT and TgAPP mice on a low-fat diet (LFD). However, HFD induced anxiety, as judged by decreased motor activity and increased time in the margins in the open-field, and a trend towards increased immobility time in the tail suspension test, with increased defecation. Intriguingly, female TgAPP mice on HFD showed less immobility and defecation compared to female WT mice on HFD. HFD induced dysbiosis of gut microbiota, resulting in reduced microbiota diversity and abundance compared with LFD fed mice, with some significant differences due to sex and little effect of genotype. Gene expression of pro-inflammatory/phagocytic markers in the hippocampus were not different between male and female WT mice, and in TgAPP mice of both sexes, some cytokines (IL-6 and IFNγ) were higher than in WT mice on LFD, more so in female TgAPP (IL-6). HFD induced few alterations in mRNA expression of inflammatory/phagocytosis-related genes in male mice, whether WT (IL-1ß, MHCII), or TgAPP (IL-6). However, in female TgAPP, altered gene expression returned towards control levels following prolonged HFD (IL-6, IL-12ß, TNFα, CD36, IRAK4, PYRY6). In summary, we demonstrate that HFD induces anxiogenic symptoms, marked alterations in gut microbiota, and increased expression of inflammatory genes, except for female TgAPP that appear to be resistant to the diet effects. Lifestyle interventions should be introduced to prevent AD onset or exacerbation by reducing inflammation and its associated symptoms; however, our results suggest that the eventual goal of developing prevention and treatment strategies should take sex into consideration.


Assuntos
Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Comportamento Animal/fisiologia , Dieta Hiperlipídica , Disbiose/genética , Microbioma Gastrointestinal/fisiologia , Inflamação/genética , Estresse Psicológico/genética , Doença de Alzheimer/fisiopatologia , Animais , Modelos Animais de Doenças , Disbiose/fisiopatologia , Feminino , Antígenos de Histocompatibilidade Classe II/genética , Humanos , Interleucina-1beta/genética , Interleucina-6/genética , Masculino , Camundongos , Camundongos Transgênicos , Fagocitose/genética , RNA Mensageiro/metabolismo , Caracteres Sexuais , Estresse Psicológico/fisiopatologia
10.
Front Neuroendocrinol ; 57: 100836, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32217094

RESUMO

The enzymatic complex 5α-reductase (5α-R) and 3α/3ß-hydroxysteroid oxidoreductase (HSOR) is expressed in the nervous system, where it transforms progesterone (PROG) and testosterone (T) into neuroactive metabolites. These metabolites regulate myelination, brain maturation, neurotransmission, reproductive behavior and the stress response. The expression of 5α-R and 3α-HSOR and the levels of PROG and T reduced metabolites show regional and sex differences in the nervous system and are affected by changing physiological conditions as well as by neurodegenerative and psychiatric disorders. A decrease in their nervous tissue levels may negatively impact the course and outcome of some pathological events. However, in other pathological conditions their increased levels may have a negative impact. Thus, the use of synthetic analogues of these steroids or 5α-R modulation have been proposed as therapeutic approaches for several nervous system pathologies. However, further research is needed to fully understand the consequences of these manipulations, in particular with 5α-R inhibitors.


Assuntos
3-Hidroxiesteroide Desidrogenases/fisiologia , Colestenona 5 alfa-Redutase/fisiologia , Progesterona/metabolismo , Testosterona/metabolismo , 3-Hidroxiesteroide Desidrogenases/genética , Animais , Encéfalo/enzimologia , Colestenona 5 alfa-Redutase/genética , Feminino , Expressão Gênica , Humanos , Masculino , Transtornos Mentais/enzimologia , Doenças Neurodegenerativas/enzimologia , Fármacos Neuroprotetores , Caracteres Sexuais
11.
Front Neuroendocrinol ; 56: 100804, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31689419

RESUMO

The nervous system, in addition to be a target for steroid hormones, is the source of a variety of neuroactive steroids, which are synthesized and metabolized by neurons and glial cells. Recent evidence indicates that the expression of neurosteroidogenic proteins and enzymes and the levels of neuroactive steroids are different in the nervous system of males and females. We here summarized the state of the art of neuroactive steroids, particularly taking in consideration sex differences occurring in the synthesis and levels of these molecules. In addition, we discuss the consequences of sex differences in neurosteroidogenesis for the function of the nervous system under healthy and pathological conditions and the implications of neuroactive steroids and neurosteroidogenesis for the development of sex-specific therapeutic interventions.


Assuntos
Doenças do Sistema Nervoso/metabolismo , Sistema Nervoso/metabolismo , Caracteres Sexuais , Esteroides/análise , Esteroides/biossíntese , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/metabolismo , Animais , Encéfalo/metabolismo , Feminino , Hormônios Esteroides Gonadais/biossíntese , Hormônios Esteroides Gonadais/fisiologia , Humanos , Masculino , Transtornos Mentais/epidemiologia , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/metabolismo , Doenças do Sistema Nervoso/epidemiologia , Doenças Neurodegenerativas/epidemiologia , Doença de Parkinson/epidemiologia , Doença de Parkinson/metabolismo
12.
Neuroendocrinology ; 111(7): 660-677, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32570260

RESUMO

INTRODUCTION: The membrane-associated G protein-coupled estrogen receptor 1 (GPER) mediates the regulation by estradiol of arginine-vasopressin immunoreactivity in the supraoptic and paraventricular hypothalamic nuclei of female rats and is involved in the estrogenic control of hypothalamic regulated functions, such as food intake, sexual receptivity, and lordosis behavior. OBJECTIVE: To assess GPER distribution in the rat hypothalamus. METHODS: GPER immunoreactivity was assessed in different anatomical subdivisions of five selected hypothalamic regions of young adult male and cycling female rats: the arcuate nucleus, the lateral hypothalamus, the paraventricular nucleus, the supraoptic nucleus, and the ventromedial hypothalamic nucleus. GPER immunoreactivity was colocalized with NeuN as a marker of mature neurons, GFAP as a marker of astrocytes, and CC1 as a marker of mature oligodendrocytes. RESULTS: GPER immunoreactivity was detected in hypothalamic neurons, astrocytes, and oligodendrocytes. Sex and regional differences and changes during the estrous cycle were detected in the total number of GPER-immunoreactive cells and in the proportion of neurons, astrocytes, and oligodendrocytes that were GPER-immunoreactive. CONCLUSIONS: These findings suggest that estrogenic regulation of hypothalamic function through GPER may be different in males and females and may fluctuate during the estrous cycle in females.


Assuntos
Astrócitos/metabolismo , Ciclo Estral/metabolismo , Hipotálamo/metabolismo , Neurônios/metabolismo , Oligodendroglia/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Caracteres Sexuais , Animais , Feminino , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar
13.
Proc Natl Acad Sci U S A ; 115(18): 4619-4624, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29674455

RESUMO

Since 2004, indoor residual spraying (IRS) and long-lasting insecticide-impregnated bednets (LLINs) have reduced the malaria parasite prevalence in children on Bioko Island, Equatorial Guinea, from 45% to 12%. After target site-based (knockdown resistance; kdr) pyrethroid resistance was detected in 2004 in Anopheles coluzzii (formerly known as the M form of the Anopheles gambiae complex), the carbamate bendiocarb was introduced. Subsequent analysis showed that kdr alone was not operationally significant, so pyrethroid-based IRS was successfully reintroduced in 2012. In 2007 and 2014-2015, mass distribution of new pyrethroid LLINs was undertaken to increase the net coverage levels. The combined selection pressure of IRS and LLINs resulted in an increase in the frequency of pyrethroid resistance in 2015. In addition to a significant increase in kdr frequency, an additional metabolic pyrethroid resistance mechanism had been selected. Increased metabolism of the pyrethroid deltamethrin was linked with up-regulation of the cytochrome P450 CYP9K1. The increase in resistance prompted a reversion to bendiocarb IRS in 2016 to avoid a resurgence of malaria, in line with the national Malaria Control Program plan.


Assuntos
Anopheles/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Inseticidas/farmacocinética , Malária/prevenção & controle , Piretrinas/farmacocinética , Animais , Anopheles/parasitologia , Guiné Equatorial/epidemiologia , Feminino , Humanos , Resistência a Inseticidas , Ilhas/epidemiologia , Malária/epidemiologia , Malária/genética , Malária/metabolismo , Controle de Mosquitos/métodos , Prevalência
14.
Salud Publica Mex ; 63(2, Mar-Abr): 232-241, 2021 Feb 26.
Artigo em Espanhol | MEDLINE | ID: mdl-33989486

RESUMO

 Objetivo. Describir la evidencia disponible sobre la trans-misión por Covid-19 e infecciones respiratorias agudas simi-lares al Covid-19 en espacios públicos abiertos. Material y métodos. La búsqueda incluyó 4 926 artículos en inglés de los años 2000 a 2020. Seis investigadores revisaron el título y el resumen de los artículos de Embase y PubMed; dos inves-tigadores revisaron los de medRxiv. Todos los investigadores revisaron textos completos y otros resolvieron las discre-pancias. Resultados. De los 21 artículos seleccionados, se observó que la presencia de virus en superficies públicas, aguas residuales y áreas exteriores no fue indicativa de trans-misión. No obstante, se observó que el uso de cubrebocas, el lavado de manos, el distanciamiento social, no asistir a eventos masivos y la movilidad individual a espacios públicos podría ayudar a reducir el riesgo de transmisión. Conclusión. Esta información podría coadyuvar a generar recomendaciones en salud pública, sin embargo, es recomendable actualizar esta revisión conforme avance la evidencia científica.


Assuntos
COVID-19/transmissão , Infecções Respiratórias/transmissão , Doença Aguda , Humanos
15.
Front Neuroendocrinol ; 55: 100787, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31513774

RESUMO

Estradiol, either from peripheral or central origin, activates multiple molecular neuroprotective and neuroreparative responses that, being mediated by estrogen receptors or by estrogen receptor independent mechanisms, are initiated at the membrane, the cytoplasm or the cell nucleus of neural cells. Estrogen-dependent signaling regulates a variety of cellular events, such as intracellular Ca2+ levels, mitochondrial respiratory capacity, ATP production, mitochondrial membrane potential, autophagy and apoptosis. In turn, these molecular and cellular actions of estradiol are integrated by neurons and non-neuronal cells to generate different tissue protective responses, decreasing blood-brain barrier permeability, oxidative stress, neuroinflammation and excitotoxicity and promoting synaptic plasticity, axonal growth, neurogenesis, remyelination and neuroregeneration. Recent findings indicate that the neuroprotective and neuroreparative actions of estradiol are different in males and females and further research is necessary to fully elucidate the causes for this sex difference.


Assuntos
Apoptose/fisiologia , Autofagia/fisiologia , Estradiol/metabolismo , Estradiol/farmacologia , Inflamação/metabolismo , Neurogênese/fisiologia , Plasticidade Neuronal/fisiologia , Neuroproteção/fisiologia , Receptores de Estrogênio/metabolismo , Caracteres Sexuais , Transdução de Sinais/fisiologia , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Feminino , Humanos , Masculino , Neurogênese/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
16.
Eur J Neurosci ; 52(1): 2756-2770, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32243028

RESUMO

Including sex is of paramount importance in preclinical and clinical stroke researches, and molecular studies dealing in depth with sex differences in stroke pathophysiology are needed. To gain insight into the molecular sex dimorphism of ischaemic stroke in rat cerebral cortex, male and female adult rats were subjected to transient middle cerebral artery occlusion. The expression of neuroglobin (Ngb) and other functionally related molecules involved in sex steroid signalling (oestrogen and androgen receptors), steroidogenesis (StAR, TSPO and aromatase) and autophagic activity (LC3B-II/LC3B-I ratio, UCP2 and HIF-1α) was assessed in the ipsilateral ischaemic and contralateral non-ischaemic hemispheres. An increased expression of Ngb was detected in the injured female cerebral cortex. In contrast, increased expression of oestrogen receptor α, GPER, StAR, TSPO and UCP2, and decreased androgen receptor expression were detected in the injured male cortex. In both sexes, the ischaemic insult induced an upregulation of LC3B-II/-I ratio, indicative of increased autophagy. Therefore, the cerebral cortex activates both sex-specific and common molecular responses with neuroprotective potential after ischaemia-reperfusion, which globally results in similar stroke outcome in both sexes. Nonetheless, these different potential molecular targets should be taken into account when neuroprotective drugs aiming to reduce brain damage in ischaemic stroke are investigated.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Autofagia , Córtex Cerebral , Modelos Animais de Doenças , Feminino , Infarto da Artéria Cerebral Média , Masculino , Neuroglobina , Ratos , Ratos Sprague-Dawley , Caracteres Sexuais , Esteroides
17.
J Neuroinflammation ; 17(1): 37, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992325

RESUMO

BACKGROUND: Tibolone is a synthetic steroid used in clinical practice for the treatment of climacteric symptoms and osteoporosis. Active metabolites of tibolone, generated in target tissues, have an affinity for estrogen and androgen receptors. Astrocytes are direct targets for estrogenic compounds and previous studies have shown that tibolone protects brain cortical neurons in association with a reduction in reactive astrogliosis in a mouse model of traumatic brain injury. Since phagocytosis is a crucial component of the neuroprotective function exerted by astrocytes, in the present study, we have assessed whether tibolone regulates phagocytosis in primary astrocytes incubated with brain-derived cellular debris. METHODS: Male and female astrocyte cell cultures were obtained from newborn (P0-P2) female and male Wistar rats. Astrocytic phagocytosis was first characterized using carboxylate beads, Escherichia coli particles, or brain-derived cellular debris. Then, the effect of tibolone on the phagocytosis of Cy3-conjugated cellular debris was quantified by measuring the intensity of Cy3 dye-emitted fluorescence in a given GFAP immunoreactive area. Before the phagocytosis assays, astrocytes were incubated with tibolone in the presence or absence of estrogen or androgen receptor antagonists or an inhibitor of the enzyme that synthesizes estradiol. The effect of tibolone on phagocytosis was analyzed under basal conditions and after inflammatory stimulation with lipopolysaccharide. RESULTS: Tibolone stimulated phagocytosis of brain-derived cellular debris by male and female astrocytes, with the effect being more pronounced in females. The effect of tibolone in female astrocytes was blocked by a selective estrogen receptor ß antagonist and by an androgen receptor antagonist. None of these antagonists affected tibolone-induced phagocytosis in male astrocytes. In addition, the inhibition of estradiol synthesis in the cultures enhanced the stimulatory effect of tibolone on phagocytosis in male astrocytes but blocked the effect of the steroid in female cells under basal conditions. However, after inflammatory stimulation, the inhibition of estradiol synthesis highly potentiated the stimulation of phagocytosis by tibolone, particularly in female astrocytes. CONCLUSIONS: Tibolone exerts sex-specific regulation of phagocytosis in astrocytes of both sexes, both under basal conditions and after inflammatory stimulation.


Assuntos
Astrócitos/efeitos dos fármacos , Inflamação/patologia , Norpregnenos/farmacologia , Fagocitose/efeitos dos fármacos , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Antagonistas de Receptores de Andrógenos/farmacologia , Animais , Estradiol/biossíntese , Antagonistas de Estrogênios/farmacologia , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Inflamação/induzido quimicamente , Lipopolissacarídeos , Masculino , Microglia/efeitos dos fármacos , Ratos , Ratos Wistar
18.
Nat Rev Neurosci ; 16(1): 17-29, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25423896

RESUMO

Hormones regulate homeostasis by communicating through the bloodstream to the body's organs, including the brain. As homeostatic regulators of brain function, some hormones exert neuroprotective actions. This is the case for the ovarian hormone 17ß-oestradiol, which signals through oestrogen receptors (ERs) that are widely distributed in the male and female brain. Recent discoveries have shown that oestradiol is not only a reproductive hormone but also a brain-derived neuroprotective factor in males and females and that ERs coordinate multiple signalling mechanisms that protect the brain from neurodegenerative diseases, affective disorders and cognitive decline.


Assuntos
Encéfalo/metabolismo , Estradiol , Neuroprostanos , Receptores de Estrogênio/fisiologia , Animais , Encéfalo/efeitos dos fármacos , Encefalopatias/tratamento farmacológico , Encefalopatias/metabolismo , Estradiol/metabolismo , Estradiol/farmacologia , Estradiol/uso terapêutico , Feminino , Humanos , Masculino , Neuroprostanos/metabolismo , Neuroprostanos/farmacologia , Neuroprostanos/uso terapêutico
19.
Global Health ; 16(1): 67, 2020 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-32711553

RESUMO

BACKGROUND: The current study builds upon a previous situation analysis of the extent to which grants from the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund) are being utilized to support operational research and implementation research (OR/IR) activities in recipient countries. The objective of this follow-up study was to identify approaches and pathways to implement an OR component into grants to the Global Fund, in four sub-Saharan African countries. Special focus was given to the Structured Operational Research and Training IniTiative (SORT IT). METHODS: The conceptual framework was based on an analysis to identify elements supporting and blocking the integration of OR, called force field analysis, and a behavioural change assessment covering aspects such as opportunity, motivation, capability and triggers to do the integration. Data were collected through online surveys and stakeholder interviews both via telephone/online conference tools and in person in four countries with a high burden of malaria and tuberculosis. These countries were Ghana, Sierra Leone, the United Republic of Tanzania and Zimbabwe. The stakeholders included programme managers, implementation partners, representatives from international organisations, academic and governmental research institutions and other individuals involved in the countries' needs assessment and National Strategic Plan development. RESULTS: We identified opportunities to integrate OR into the countries' programmes during the funding process, the country's needs assessment being the most important one, including the need of OR-related capacity. Both the force field analysis and the behavioural change assessment showed that the necessary elements to integrate OR were present in the countries. Motivation, capability and efficiency were found to be a managerial value omnipresent across stakeholders. However, those elements were influenced by the tendency to favour tangible assets over any abstract ones, such as increasing organisational capacity in OR. CONCLUSIONS: In each of the countries assessed, there is potential to integrating OR into the programmes supported by the Global Fund. However, given the relative lack of OR-related capacity and skills encountered, a capacity strengthening tool, such as SORT IT, would be of benefit helping to identify and carry forward OR activities sustainably.


Assuntos
Síndrome da Imunodeficiência Adquirida/terapia , Saúde Global , Política de Saúde , Malária/terapia , Prevenção Primária , Tuberculose/terapia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Administração Financeira , Organização do Financiamento , Seguimentos , Humanos , Cooperação Internacional , Malária/epidemiologia , Pesquisa Operacional , Tuberculose/epidemiologia
20.
Front Neuroendocrinol ; 50: 18-30, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28974386

RESUMO

Parkinson's disease (PD) is the second most frequent age-related neurodegenerative disorder. Sex is an important factor in the development of PD, as reflected by the fact that it is more common in men than in women by an approximate ratio of 2:1. Our hypothesis is that differences in PD among men and women are highly determined by sex-dependent differences in the nigrostriatal dopaminergic system, which arise from environmental, hormonal and genetic influences. Sex hormones, specifically estrogens, influence PD pathogenesis and might play an important role in PD differences between men and women. The objective of this review was to discuss the PD physiopathology and point out sex differences in nigrostriatal degeneration, symptoms, genetics, responsiveness to treatments and biochemical and molecular mechanisms among patients suffering from this disease. Finally, we discuss the role estrogens may have on PD sex differences.


Assuntos
Hormônios Esteroides Gonadais/metabolismo , Avaliação de Resultados em Cuidados de Saúde , Doença de Parkinson , Caracteres Sexuais , Animais , Feminino , Humanos , Masculino , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA