RESUMEN
The female brain is highly dynamic and can fundamentally remodel throughout the normal ovarian cycle as well as in critical life stages including perinatal development, pregnancy and old-age. As such, females are particularly vulnerable to infections, psychological disorders, certain cancers, and cognitive impairments. We will present the latest evidence on the female brain; how it develops through the neonatal period; how it changes through the ovarian cycle in normal individuals; how it adapts to pregnancy and postpartum; how it responds to illness and disease, particularly cancer; and, finally, how it is shaped by old age. Throughout, we will highlight female vulnerability to and resilience against disease and dysfunction in the face of environmental challenges.
Asunto(s)
Encéfalo/metabolismo , Neuroinmunomodulación/fisiología , Plasticidad Neuronal/fisiología , Factores de Edad , Encéfalo/inmunología , Femenino , Humanos , Longevidad , Plasticidad Neuronal/inmunología , Embarazo , Mujeres Embarazadas , Psiconeuroinmunología , Psicopatología , Resiliencia PsicológicaRESUMEN
Early-life stress (ES) is a risk factor for metabolic disorders (e.g. obesity) with a notoriously higher prevalence in women compared to men. However, mechanisms underlying these effects remain elusive. The development of the hypothalamic feeding and metabolic regulatory circuits occurs mostly in the early sensitive postnatal phase in rodents and is tightly regulated by the metabolic hormones leptin and ghrelin. We have previously demonstrated that chronic ES reduces circulating leptin and alters adipose tissue metabolism early and later in life similarly in both sexes. However, it is unknown whether chronic ES might also affect developmental ghrelin and insulin levels, and if it induces changes in hypothalamic feeding circuits, possibly in a sex-dependent manner. We here show that chronic ES, in the form of exposure to limited nesting and bedding material from postnatal day (P)2 to P9 in mice, affects ghrelin levels differently, depending on the form of ghrelin (acylated vs desacylated), on age (P9 vs P14) and on sex, while insulin levels were similarly increased in both sexes after ES at P9. Even though ghrelin levels were more strongly affected in ES-exposed females, hypothalamic neuropeptide Y (NPY) and agouti-related peptide (AgRP) fiber density at P14 were similarly altered in both sexes by ES. In the paraventricular nucleus of the hypothalamus, both NPY and AgRP fiber density were increased, while in the arcuate nucleus of the hypothalamus, NPY was increased and AgRP unaltered. Additionally, the hypothalamic mRNA expression of ghrelin's receptor (i.e. growth hormone secretagogue receptor) was not affected by ES. Taken together, the specific alterations found in these important regulatory circuits after ES might contribute to an altered energy balance and feeding behavior in adulthood and thereby to an increased vulnerability to develop metabolic disorders.
Asunto(s)
Proteína Relacionada con Agouti/metabolismo , Ghrelina/metabolismo , Neuropéptido Y/metabolismo , Tejido Adiposo/metabolismo , Proteína Relacionada con Agouti/farmacología , Animales , Núcleo Arqueado del Hipotálamo/citología , Núcleo Arqueado del Hipotálamo/metabolismo , Conducta Alimentaria/efectos de los fármacos , Femenino , Ghrelina/genética , Ghrelina/farmacología , Hipotálamo/metabolismo , Insulina/genética , Insulina/metabolismo , Insulina/farmacología , Leptina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Neuropéptido Y/farmacología , Obesidad/metabolismo , Núcleo Hipotalámico Paraventricular/citología , Núcleo Hipotalámico Paraventricular/metabolismo , Factores Sexuales , Estrés Psicológico/fisiopatologíaRESUMEN
OBJECTIVES: Estrogen is often prescribed for symptoms and sequelae of ovarian estrogen loss after menopause. METHODS: To assess efficacy and acceptability of a new, highly soluble estrogen-calcium preparation, we formulated a water-soluble powdered combination of estrogen (0.625 mg estrone piperazine sulfate) and calcium (1 g, ions) as the highly soluble glycerophosphate salt (Estrosol). Effects of once-daily administration on bone mineral turnover of Estrosol dissolved in water (n = 11) was compared with 0.625 mg conjugated estrogens (Premarin) + 1 g calcium (Tums 500 Calcium Supplement) (n = 8). All women had had a previous hysterectomy, were between the ages 40 and 75, within 25% of ideal body weight, and had not taken hormonal preparations for at least 3 months. Assessment of bone mineral turnover was by monitoring N-telopeptides and bone specific alkaline phosphatase (BSAP) on 5 occasions: pretreatment and once during each of the 4 months of treatment. RESULTS: Mean N-telopeptide values decreased (p = .005) in both groups: Estrosol, 29.2% (40 --> 29 mmol bone collagen equivalents (BCE)/mmol creatinine), and Premarin(R) + calcium, 44.8% (33 --> 18 mmol). Mean BSAP values also decreased (p = 0.007) in both groups: Estrosol, 12.6% (12.06 --> 10.54 mg/l), Premarin(R) + calcium, 19.1% (11.57 --> 9.36 mg/l). The difference between groups for both N-telopeptides and BSAP was not significant, although sample size was small. Symptoms (hot flashes, vaginal dryness) improved similarly in both groups. Symptoms during treatment (breast or nipple tenderness, bloating) also were similar in both groups. Both preparations were well-tolerated. There were no changes in CBC, liver function tests, electrolytes or urinalyses in either group . CONCLUSIONS: This pilot study indicates that the combined, highly water-soluble preparation of estrogen and calcium is effective in reducing bone mineral turnover, acceptable and well-tolerated. Use of this single aqueous preparation may lead to better compliance than using two separate pills.