Gonadal hormone deprivation regulates response to tibolone in neurodegenerative pathways.

Gonadal hormone deprivation (GHD) and decline such as menopause and bilateral oophorectomy are associated with an increased risk of neurodegeneration. Yet, hormone therapies (HTs) show varying efficacy, influenced by factors such as sex, drug type, and timing of treatment relative to hormone decline. We hypothesize that the molecular environment of the brain undergoes a transition following GHD, impacting the effectiveness of HTs. Using a GHD model in mice treated with Tibolone, we conducted proteomic analysis and identified a reprogrammed response to Tibolone, a compound that stimulates estrogenic, progestogenic, and androgenic pathways. Through a comprehensive network pharmacological workflow, we identified a reprogrammed response to Tibolone, particularly within "Pathways of Neurodegeneration", as well as interconnected pathways including "cellular respiration", "carbon metabolism", and "cellular homeostasis". Analysis revealed 23 proteins whose Tibolone response depended on GHD and/or sex, implicating critical processes like oxidative phosphorylation and calcium signalling. Our findings suggest the therapeutic efficacy of HTs may depend on these variables, suggesting a need for greater precision medicine considerations whilst highlighting the need to uncover underlying mechanisms.

Sex chromosome complement interacts with gonadal hormones in determining regional-specific neuroactive steroid levels in plasma, hippocampus, and hypothalamus. A study using the four core genotype mouse model.

An important aspect of the neuromodulatory and neuroprotective actions exerted by neuroactive steroids is that they are sex-specific, as determined by the sexually dimorphic levels of these molecules in plasma and the nervous tissue. Thus, the identification of the factors that generate the sex-dimorphic levels of neuroactive steroids may be crucial from a neuroprotectant perspective. The main driver for sex determination in mammals is the SRY gene and the subsequent presence of a specific gonad: testes for males and ovaries for females, thus producing hormonal compounds, primarily androgens and estrogens, respectively. Nowadays, it is well established that despite the relevance of gonads, other factors control sexual features, and, among them, sex chromosome complement is highly relevant. In this study, neuroactive steroids were evaluated by liquid chromatography-tandem mass spectrometry in the hypothalamus, the hippocampus, and plasma of the four core genotype mouse model, to determine the relative contribution of sex chromosome complement and gonads in determining their sex dimorphic levels. The data obtained reveal that although gonads are the main contributing factor for sex differences in neuroactive steroid levels, the levels of some neuroactive steroids, including testosterone, are also influenced in brain and plasma by tissue-specific actions of sex chromosomes. The data presented here adds a new piece to the puzzle of steroid level regulation, which may be useful in designing sex-specific neuroprotective approaches to pathological conditions affecting the nervous system.

Neonatal inhibition of androgen activity alters the programming of body weight and orexinergic peptides differentially in male and female rats.

The involvement of androgens in the regulation of energy metabolism has been demonstrated. The main objective of the present research was to study the involvement of androgens in both the programming of energy metabolism and the regulatory peptides associated with feeding. For this purpose, androgen receptors and the main metabolic pathways of testosterone were inhibited during the first five days of postnatal life in male and female Wistar rats. Pups received a daily s.c. injection from the day of birth, postnatal day (P) 1, to P5 of Flutamide (a competitive inhibitor of androgen receptors), Letrozole (an aromatase inhibitor), Finasteride (a 5-alpha-reductase inhibitor) or vehicle. Body weight, food intake and fat pads were measured. Moreover, hypothalamic Agouti-related peptide (AgRP), neuropeptide Y (NPY), orexin, and proopiomelanocortin (POMC) were analyzed by quantitative real-time polymerase chain reaction assay. The inhibition of androgenic activity during the first five days of life produced a significant decrease in body weight in females at P90 but did not affect this parameter in males. Moreover, the inhibition of aromatase decreased hypothalamic AgRP mRNA levels in males while the inhibition of 5α-reductase decreased hypothalamic AgRP and orexin mRNA levels in female rats. Finally, food intake and visceral fat, but not subcutaneous fat, were affected in both males and females depending on which testosterone metabolic pathway was inhibited. Our results highlight the differential involvement of androgens in the programming of energy metabolism as well as the AgRP and orexin systems during development in male and female rats.

Hábitos de alimentación infantil y su relación con las prácticas y conocimientos nutricionales parentales

Objetivo: Evaluar la relación entre las prácticas parentales de alimentación, los conocimientos nutricionales de los padres y los hábitos de alimentación infantil reportados por padres de cuatro instituciones educativas del suroccidente de Colombia. Método: Estudio observacional con diseño transversal correlacional. Se analizaron los datos de 1.162 padres de niñas y niños matriculados en los grados de preescolar hasta tercero de primaria de cuatro instituciones educativas públicas, quienes contestaron cuestionarios de autoinforme. Se realizaron análisis descriptivos e inferenciales. Resultados: La dieta de las niñas y los niños se caracteriza por un consumo frecuente de alimentos ultraprocesados y un consumo de frutas y verduras menor de lo esperado. Se encontraron relaciones entre las prácticas parentales de alimentación responsivas y el consumo de alimentos saludables en los hijos, así como entre las prácticas autoritarias y permisivas con el consumo frecuente de alimentos ultraprocesados. El nivel de conocimiento nutricional de los padres no se relacionó con la dieta de las niñas y los niños; sin embargo, se encontró una relación entre las prácticas parentales responsivas, un bajo nivel de conocimientos nutricionales de los padres y una baja frecuencia de consumo de frutas y verduras en los hijos. Conclusión: La alimentación es un fenómeno complejo, e implica la interacción entre los factores individuales y contextuales; en esta medida, la promoción de hábitos saludables involucra un trabajo conjunto en los múltiples niveles de interacción. Se espera que los resultados de este estudio posibiliten la construcción de intervenciones interdisciplinares oportunas, en poblaciones de bajos y medios ingresos en el territorio observado.

Purpose: To evaluate the relationship between parental feeding practices, parental nutritional knowledge, and child feeding habits reported by parents in four educational institutions in southwestern Colombia. Method: Observational study with correlational cross-sectional design. Data were analysed from 1.162 parents of children enroled in grades from preschool to third grade from four public educational institutions. Parents answered self-report questionnaires. Descriptive and inferential analyses were performed. Results: The children's diet is characterised by frequent consumption of ultra-processed food and a lower consumption of fruits and vegetables. Relationships were found between responsive parenting practices and healthy food consumption in children, as well as between authoritarian and permissive practices with frequent consumption of ultra-processed foods. The level of nutritional knowledge of parents was not related to the children's diet; however, a relationship was found between responsive parenting practices, a low level of nutritional knowledge of parents, and a low frequency of fruit and vegetable consumption in children. Conclusion: Eating is a complex phenomenon and involves the interaction between individual and contextual factors. To this extent, the promotion of healthy habits involves joint work at multiple levels of interaction. The results of this study are expected to allow the construction of timely interdisciplinary interventions in low- and middle-income populations in the observed territory.

La gestión para la evaluación de las competencias en la formación del profesional de Cultura Física

La evaluación, como categoría didáctica en el proceso de enseñanza-aprendizaje de la carrera Licenciatura en Cultura Física y Deporte, enfrenta desafíos que obligan a los diferentes colectivos pedagógicos a proyectar acciones que le permitan una visión contextualizada e integral de la misma. La unidad del sistema de influencias educativas es una necesidad para la evaluación formativa, compartida, personalizada, centrada en evidencias de conocimiento, de producto y de desempeño en la formación y desarrollo de competencias en esta Carrera. El objetivo del trabajo es valorar el proceso evaluativo integrador de las competencias, en los estudiantes de la Práctica Laboral Investigativa de tercer año, de la Carrera de licenciatura en Cultura Física y Deporte, a través de la disciplina principal integradora Formación Laboral Investigativa. Para ello, se aplicaron métodos de investigación empíricos, como el análisis de documentos, la entrevista y la observación. Los resultados permitieron fundamentar una propuesta metodológica que potencie la evaluación integradora, sobre la base el enfoque integral físico-educativo, en el proceso de estudio. El diseño de los resultados fue de tipo experimental, en su variante pre-experimento. La aplicación parcial de la propuesta validó su pertinencia y contribuyó de forma favorable al mejoramiento del desempeño profesional y humano de los que participan.

A avaliação, como categoria didática no processo de ensino-aprendizagem do curso de Bacharelado em Cultura Física e Esporte, enfrenta desafios que obrigam os diferentes coletivos pedagógicos a planejar ações que permitam uma visão contextualizada e integral da mesma. A unidade do sistema de influências educacionais é uma necessidade para a avaliação formativa, compartilhada e personalizada, focada na evidência de conhecimento, produto e desempenho na formação e no desenvolvimento de competências nesse curso de graduação. O objetivo do estudo é avaliar o processo de avaliação integrativa das competências dos alunos do terceiro ano do Estágio de Pesquisa no Bacharelado em Cultura Física e Esporte, por meio da principal disciplina integrativa do Estágio de Pesquisa. Para isso, foram aplicados métodos de pesquisa empírica, como análise de documentos, entrevista e observação. Os resultados permitiram fundamentar uma proposta metodológica que aprimora a avaliação integrativa, com base na abordagem físico-educacional integral, no processo de estudo. O desenho dos resultados foi experimental, em sua variante pré-experimental. A aplicação parcial da proposta validou sua relevância e contribuiu favoravelmente para a melhoria do desempenho profissional e humano dos envolvidos.

Evaluation, as a didactic category in the teaching-learning process of the Bachelor's Degree in Physical Culture and Sports, faces challenges that force the different pedagogical groups to project actions that allow a contextualized and comprehensive vision of it. The unity of the system of educational influences is a necessity for formative, shared, personalized evaluation, focused on evidence of knowledge, product and performance in the training and development of competencies in this Career. The objective of the work is to assess the integrative evaluative process of the competencies, in the students of the third-year Investigative Work Practice, of the Bachelor's Degree in Physical Culture and Sports, through the main integrative discipline Investigative Work Training. To achieve this, empirical research methods were applied, such as document analysis, interviews and observation. The results allowed to base a methodological proposal that enhances the integrative evaluation, based on the comprehensive physical-educational approach, in the study process. The design of the results was experimental, in its pre-experiment variant. The partial application of the proposal validated its relevance and contributed favorably to the improvement of the professional and human performance of those who participate.

Interaction of gonadal hormones, dopaminergic system, and epigenetic regulation in the generation of sex differences in substance use disorders: A systematic review.

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.

Complete, circular genome sequence of a Bosea sp. isolate from soil.

Here, we report the complete, circular genome sequence of a potential novel species from the underexplored Alphaproteobacterial genus Bosea. Bosea sp. NBC_00550 was isolated from a soil sample collected in Lyngby, Denmark. We explore the biosynthetic potential of Bosea sp. NBC_00550 and compare it with that of other Bosea species.

An expert patient program to improve the empowerment and quality of life of people with multiple sclerosis: protocol for a multicenter pre-post intervention study.

Introduction: Multiple sclerosis (MS) causes a progressive disability, which substantially impacts the quality of life (QoL). Health interventions that meet the needs and demands of people with MS are essential to minimize QoL impairment. Expert patient programs (EPPs) facilitate health-related empowerment through peer learning. Based on a previous focus group study, we designed an EPP for MS coordinated by nursing professionals for implementation in the different MS reference units of Catalonia (Southwestern Europe). This study aims to evaluate the effects on quality of life, disease-related knowledge, and self-management related to the health process of the participants of the Expert Patient Program Catalonia™ for people with multiple sclerosis (EPPC-MS). Methods: Pre-post intervention multicenter clinical study involving 12 groups of 12 participants: six groups including relapsing and six groups including progressive MS patients, with 144 participants from 7 MS reference units from all over Catalonia, organized in six teams. The intervention will consist of nine telematic learning peer-led sessions (one weekly session). The expert patient (EP) leading the sessions will be an individual with MS with disease-related knowledge, who will be further trained by nurses to lead the sessions. Study variables will be measured before and immediately after the intervention and 6 and 12 months after the end of the sessions and will include: QoL, emotional impact, activation of the person, MS-related knowledge, fatigue, habits and lifestyles, health services use, and program-related experience. Baseline characteristics considered will be sociodemographic data, date of MS diagnosis and type, family history, and treatment characteristics. Variables related to disease follow-up will be new relapses and characteristics and changes in the ongoing treatment. The number of sessions attended will also be collected. Study variables will be analyzed using a pre-post comparison. Discussion: Peer-led learning programs led by EP help empower people with chronic conditions and offer them tools to improve their autonomy and QoL. This study's intervention will be performed remotely, offering advantages both for people with chronic conditions and the healthcare system regarding the facilitation of family and work conciliation, saving time, simplifying attendance to meetings, lowering costs, and using fewer material resources. Trial registration: NCT04988880 on September 22, 2021.

Complete Genome Sequences of the Two Strains Methylorubrum extorquens NBC_00036 and NBC_00404.

Here, we report the complete genome sequences of Methylorubrum extorquens NBC_00036 and Methylorubrum extorquens NBC_00404. The genomes were sequenced using the Oxford Nanopore Technologies MinION and Illumina NovaSeq systems. Both genomes are circular, with sizes of 5,661,342 bp and 5,869,086 bp, respectively.

Crossiellidines A-F, Unprecedented Pyrazine-Alkylguanidine Metabolites with Broad-Spectrum Antibacterial Activity from Crossiella sp.

Crosiellidines are intriguing pyrazine-alkylguanidine metabolites isolated from the minor actinomycete genus Crossiella. Their structures present an unprecedented 2-methoxy-3,5,6-trialkyl pyrazine scaffold and uncommon guanidine prenylations, including an exotic O-prenylated N-hydroxyguanidine moiety. The novel substitution pattern of the 2-methoxypyrazine core inaugurates a new class of naturally occurring pyrazine compounds, the biosynthetic implications of which are discussed herein. Isotopic feeding and genome analysis allowed us to propose a biosynthetic pathway from arginine. The crossiellidines exhibited remarkable, broad-spectrum antibacterial activity.

Kif21B mediates the effect of estradiol on the morphological plasticity of mouse hippocampal neurons.

Introduction: Neurons are polarized cells, and their ability to change their morphology has a functional implication in the development and plasticity of the nervous system in order to establish new connections. Extracellular factors strongly influence neuronal shape and connectivity. For instance, the developmental actions of estradiol on hippocampal neurons are well characterized, and we have demonstrated in previous studies that Ngn3 mediates these actions. On the other hand, Kif21B regulates microtubule dynamics and carries out retrograde transport of the TrkB/brain-derived neurotrophic factor (BDNF) complex, essential for neuronal development. Methods: In the present study, we assessed the involvement of kinesin Kif21B in the estradiol-dependent signaling mechanisms to regulate neuritogenesis through cultured mouse hippocampal neurons. Results: We show that estradiol treatment increases BDNF expression, and estradiol and BDNF modify neuron morphology through TrkB signaling. Treatment with K252a, a TrkB inhibitor, decreases dendrite branching without affecting axonal length, whereas. Combined with estradiol or BDNF, it blocks their effects on axons but not dendrites. Notably, the downregulation of Kif21B abolishes the actions of estradiol and BDNF in both the axon and dendrites. In addition, Kif21B silencing also decreases Ngn3 expression, and downregulation of Ngn3 blocks the effect of BDNF on neuron morphology. Discussion: These results suggest that Kif21B is required for the effects of estradiol and BDNF on neuronal morphology, but phosphorylation-mediated activation of TrkB is essential only for axonal growth. Our results show that the Estradiol/BDNF/TrkB/Kif21B/Ngn3 is a new and essential pathway mediating hippocampal neuron development.

Postnatal catch-up growth in term newborns with altered fetal weight patterns. The GROWIN study.

BACKGROUND: Small for gestational age (SGA) perform a postnatal catch-up growth to recover their genetic trajectory. We studied the postnatal catch-up growth pattern of fetuses born with an appropriate-for-gestational-age (AGA) weight but with fetal growth deceleration (FGD) to explore whether they catch up. METHODS: Nine hundred and sixty-six newborns at Villalba University General Hospital (HUGV), were followed from 34 to 37 weeks to birth. Z-scores, adjusted for sex and age, of weight, length, and BMI at 3, 6, 9, and 12 months were calculated. We define catch-up as an increase in z-score greater than 0.67 SD in the growth curves. RESULTS: AGA FGD had lower mean weight and length than AGA non-FGD at all time points; BMI was lower until 3 months. AGA FGD had a lower weight, length, and BMI z-score (until 9, 6 months, and at birth, respectively) than AGA non-FGD. AGA FGD newborns had a significantly increased likelihood of weight catch-up at 3 months (OR 1.79; 95% CI: 1.16, 2.78; p = 0.009) and BMI in all investigated periods (OR 1.90; 95% CI 1.30, 2.78; p < 0.001 at 3 months), compared to AGA non-FGD newborns. CONCLUSIONS: AGA FGD newborns perform catch-up growth, especially in weight and BMI, in the first year of life, compared to AGA non-FGD. IMPACT: Appropriate-for-gestational-age (AGA) newborns with fetal growth deceleration (FGD), between the third trimester of pregnancy and delivery, present a lower weight and height, during the first year of life, compared to AGA non-FGD. Appropriate-for-gestational-age (AGA) newborns with fetal growth deceleration (FGD), between the third trimester of pregnancy and delivery, present a higher likelihood of weight catch-up in the first 3 months of life and of BMI in the first year compared to AGA non-FGD. AGA FGD experienced early weight and BMI catch-up, especially in the first 3 months of life, like SGA. This finding should be considered in the future follow-up.

Validation of the Spanish version of DYsphagia in MUltiple Sclerosis questionnaire (DYMUS).

BACKGROUND: Dysphagia is a common symptom in multiple sclerosis that can occur even early in the disease course and can lead to serious complications. Early recognition and treatment can promote comfort, safety and optimal nutritional status. Few dysphagia rating scales are available in Spanish. The aim of this study was to translate the Dysphagia in Multiple Sclerosis Questionnaire (DYMUS) into Spanish and to validate it. METHODS: Forward and backward translation method was used to translate the original English version of DYMUS into Spanish. A pilot-study with 10 PwMS was carried on in order to improve the intelligibility of the instrument, comprehensibility and content validity of the questionnaire. The questionnaire was filled out by 100 PwMS who were asked a dichotomous question on their swallowing ("Do you have swallowing troubles?"). Descriptive data are presented as median and quartiles for continuous variables and frequency and percentage for categorical ones. Internal consistency reliability was estimated by Cronbach's alfa. Test-retest reliability was estimated by intraclass correlation coefficient. Concurrent validity with a speech and language therapy assessment (SLT-A) was measured with the weighted kappa statistic for the concordance for both dysphagia type and degree categories. Confirmatory factor analysis by means of structural equation models was used to verify the two-factor (solids and liquids) structure of the DYMUS questionnaire. As the goodness of fit evaluation was poor, an additional exploratory factor analysis was carried out. RESULTS: Internal consistency was high. The globus sensation question and the weight loss questions (item 3 and 10) are the least specific with dysphagia symptomatology so they are worst correlated with the sum of the others (item-rest correlation, 0.243 and 0.248, respectively). The test-retest reliability of the DYMUS among 40 patients using ICC was 0.75 (95% CI 0.57 - 0.86). Concurrent validity with SLT-A was poor (weighted kappa 0.37 for dysphagia type and 0.38 for dysphagia degree). The DYMUS questionnaire detected three times more dysphagia (53% versus 17%) than the dichotomous question. Confirmatory factors analysis failed to confirm the bidimensional structure (solid and liquid items) often reported in other validation studies. The subsequent exploratory factor analysis also identified two factors, but with poor interpretability. CONCLUSION: DYMUS-SP scale is not a sufficiently useful scale to detect dysphagia in PwMS due to the poor concurrent validity and the probable overdiagnosis of the condition; however, it can be helpful as a screening tool when combined with other measures.

Extraction and Oxford Nanopore sequencing of genomic DNA from filamentous Actinobacteria.

Actinomycetota (Actinobacteria) is an ecologically and industrially important phylum which is challenging to extract pure high-molecular-weight (HMW) DNA from. This protocol provides a parallelized, cost-effective, and straightforward approach for consistently extracting pure HMW DNA using modified non-toxic commercial kits suitable for higher throughput applications. We further provide a workflow for sequencing and assembly of complete genomes using an optimized Oxford Nanopore rapid barcoding protocol and Illumina data error correction.

Respirasome Proteins Are Regulated by Sex-Hormone Interactions in the Brain.

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.

High levels of HDAC expression correlate with microglial aging.

BACKGROUND: Cellular damage gradually accumulates with aging, promoting a time-dependent functional decline of the brain. Microglia play an essential regulatory role in maintaining cognitive activity by phagocytosing cell debris and apoptotic cells during neurogenesis. The activities of different histone deacetylases (HDACs) regulate microglial function during development and neurodegeneration. However, no studies have described the role of HDACs in microglia during physiological aging. RESEARCH DESIGN AND METHODS: HDAC and microglial marker levels were examined in microglial cells after inducing senescence in vitro and in mouse and human hippocampal biopsies in vivo, using quantitative real-time PCR. Publicly available datasets were used to determine HDAC expression in different brain areas during physiological aging. RESULTS: HDAC expression increased upon the induction of senescence with bleomycin or serial passage in microglial cultures. High levels of HDACs were detected in mice and aged human brain samples. Human hippocampal samples showed a positive correlation between the expression of HDAC1, 3, and 7 and microglial and senescence markers. HDAC1 and 3 levels are enriched in the purified aged microglial population. CONCLUSIONS: Several HDACs, particularly HDAC1, are elevated in microglia upon senescence induction in vitro and with aging in vivo, and correlate with microglial and senescence biomarkers.

IGF1 gene therapy in middle-aged female rats delays reproductive senescence through its effects on hypothalamic GnRH and kisspeptin neurons.

The process of aging is the result of progressive loss of homeostasis and functional body impairment, including the central nervous system, where the hypothalamus plays a key role in regulating aging mechanisms. The consequences of aging include a chronic proinflammatory environment in the hypothalamus that leads to decreased secretion of gonadotropin-releasing hormone (GnRH) and impairs kisspeptin neuron functionality. In this work, we investigated the effect of insulin-like growth factor 1 (IGF1) gene therapy on hypothalamic kisspeptin/GnRH neurons and on microglial cells, that mediate the inflammatory process related with the aging process. The results show that IGF1 rats have higher kisspeptin expression in the anteroventral periventricular (AVPV) nucleus and higher immunoreactivity of GnRH in the arcuate nucleus and median eminence. In addition, IGF1-treated animals exhibit increased numbers of Iba1+ microglial cells and MHCII+/Iba1+ in the AVPV and arcuate nuclei. In conclusion, IGF1 gene therapy maintains kisspeptin production in the AVPV nucleus, induces GnRH release in the median eminence, and alters the number and reactivity of microglial cells in middle-aged female rats. We suggest that IGF1 gene therapy may have a protective effect against reproductive decline.

Epigenetic modifier Kdm6a/Utx controls the specification of hypothalamic neuronal subtypes in a sex-dependent manner.

Kdm6a is an X-chromosome-linked H3K27me2/3 demethylase that promotes chromatin accessibility and gene transcription and is critical for tissue/cell-specific differentiation. Previous results showed higher Kdm6a levels in XX than in XY hypothalamic neurons and a female-specific requirement for Kdm6a in mediating increased axogenesis before brain masculinization. Here, we explored the sex-specific role of Kdm6a in the specification of neuronal subtypes in the developing hypothalamus. Hypothalamic neuronal cultures were established from sex-segregated E14 mouse embryos and transfected with siRNAs to knockdown Kdm6a expression (Kdm6a-KD). We evaluated the effect of Kdm6a-KD on Ngn3 expression, a bHLH transcription factor regulating neuronal sub-specification in hypothalamus. Kdm6a-KD decreased Ngn3 expression in females but not in males, abolishing basal sex differences. Then, we analyzed Kdm6a-KD effect on Ascl1, Pomc, Npy, Sf1, Gad1, and Th expression by RT-qPCR. While Kdm6a-KD downregulated Ascl1 in both sexes equally, we found sex-specific effects for Pomc, Npy, and Th. Pomc and Th expressed higher in female than in male neurons, and Kdm6a-KD reduced their levels only in females, while Npy expressed higher in male than in female neurons, and Kdm6a-KD upregulated its expression only in females. Identical results were found by immunofluorescence for Pomc and Npy neuropeptides. Finally, using ChIP-qPCR, we found higher H3K27me3 levels at Ngn3, Pomc, and Npy promoters in male neurons, in line with Kdm6a higher expression and demethylase activity in females. At all three promoters, Kdm6a-KD induced an enrichment of H3K27me3 only in females. These results indicate that Kdm6a plays a sex-specific role in controlling the expression of transcription factors and neuropeptides critical for the differentiation of hypothalamic neuronal populations regulating food intake and energy homeostasis.

Genetics and Epigenetics of the X and Y Chromosomes in the Sexual Differentiation of the Brain.

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.

Sex Differences in Hypothalamic Changes and the Metabolic Response of TgAPP Mice to a High Fat Diet.

The propensity to develop neurodegenerative diseases is influenced by diverse factors including genetic background, sex, lifestyle, including dietary habits and being overweight, and age. Indeed, with aging, there is an increased incidence of obesity and neurodegenerative processes, both of which are associated with inflammatory responses, in a sex-specific manner. High fat diet (HFD) commonly leads to obesity and markedly affects metabolism, both peripherally and centrally. Here we analyzed the metabolic and inflammatory responses of middle-aged (11-12 months old) transgenic amyloid precursor protein (TgAPP) mice of both sexes to HFD for 18 weeks (starting at 7-8 months of age). We found clear sex differences with females gaining significantly more weight and fat mass than males, with a larger increase in circulating leptin levels and expression of inflammatory markers in visceral adipose tissue. Glycemia and insulin levels increased in HFD fed mice of both sexes, with TgAPP mice being more affected than wild type (WT) mice. In the hypothalamus, murine amyloid ß (Aß) levels were increased by HFD intake exclusively in males, reaching statistical significance in TgAPP males. On a low fat diet (LFD), TgAPP males had significantly lower mRNA levels of the anorexigenic neuropeptide proopiomelanocortin (POMC) than WT males, with HFD intake decreasing the expression of the orexigenic neuropeptides Agouti-related peptide (AgRP) and neuropeptide Y (NPY), especially in TgAPP mice. In females, HFD increased POMC mRNA levels but had no effect on AgRP or NPY mRNA levels, and with no effect on genotype. There was no effect of diet or genotype on the hypothalamic inflammatory markers analyzed or the astrogliosis marker glial acidic protein (GFAP); however, levels of the microglial marker Iba-1 increased selectively in male TgAPP mice. In summary, the response to HFD intake was significantly affected by sex, with fewer effects due to genotype. Hypothalamic inflammatory cytokine expression and astrogliosis were little affected by HFD in middle-aged mice, although in TgAPP males, which showed increased Aß, there was microglial activation. Thus, excess intake of diets high in fat should be avoided because of its possible detrimental consequences.