Hormones and depression in women

ABSTRACT The biological plausibility for the effect of sex hormones on the central nervous system is now supported by a considerable amount of clinical data. This critical review guides the reader through the plethora of data, from the earliest reports of menstrual madness in the nineteenth century to neurobiological work in the new millennium. It illustrates through the scientific evidence base that, although the effect of estrogen on the central nervous system, particularly on mood and depression, remains a controversial area, there is now considerable evidence for the psychotherapeutic benefits of estrogens in the triad of hormone-responsive depressive disorders: postnatal depression, premenstrual depression and perimenopausal depression. The article also reviews the compelling data that testosterone supplementation has positive effects for depression, libido and energy, particularly where patients have only partially responded to estrogen therapy

Density estimates for Canada lynx vary among estimation methods

Abstract Unbiased population density estimates are critical for ecological research and wildlife management but are often difficult to obtain. Researchers use a variety of sampling and statistical methods to generate estimates of density, but few studies have compared estimates across methods. During 2016–2017, we surveyed Canada lynx (Lynx canadensis) in southwestern Yukon Territory, Canada, using track transect counts, hair snares, camera traps, live traps, and Global Positioning System (GPS) collars. From these data, we estimated lynx density with two linearly scaled count methods, one spatial mark–recapture method, three spatial mark–resight methods, and one cumulative‐time method. We found up to fivefold variation in point density estimates despite adhering to method requirements and assumptions in a manner consistent with other studies. Our results highlight the dependency of density estimates on sampling process and model assumptions and demonstrate the value of careful and unbiased sampling design. Further research is needed to fully assess the accuracy and limitations of the many wildlife density estimation methods that are currently in use so that techniques can be appropriately applied to typical study systems and species

Optimisation of energetic and reproductive gains explains behavioural responses to environmental variation across seasons and years

Animals switch between inactive and active states, simultaneously impacting their energy intake, energy expenditure and predation risk, and collectively defining how they engage with environmental variation and trophic interactions. We assess daily activity responses to long‐term variation in temperature, resources and mating opportunities to examine whether individuals choose to be active or inactive according to an optimisation of the relative energetic and reproductive gains each state offers. We show that this simplified behavioural decision approach predicts most activity variation (R2 = 0.83) expressed by free‐ranging red squirrels over 4 years, as quantified through accelerometer recordings (489 deployments; 5066 squirrel‐days). Recognising activity as a determinant of energetic status, the predictability of activity variation aggregated at a daily scale, and the clear signal that behaviour is environmentally forced through optimisation of gain, provides an integrated approach to examine behavioural variation as an intermediary between environmental variation and energetic, life‐history and ecological outcomes.By assessing daily activity responses to long‐term variation in temperature, resources, and mating opportunities, we examine whether individuals choose to be active or inactive according to an optimization of energetic and reproductive gains. This simplified behavioural decision approach predicts most daily activity variation (R2 = 0.83) expressed by free‐ranging red squirrels over four years, as quantified through accelerometer recordings. Here we provide an integrated approach to examine behavioural variation as an intermediary between environmental variation and energetic, life‐history, and ecological outcomes.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154889/1/ele13494_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154889/2/ele13494.pd

Sex differences in intestinal carbohydrate metabolism promote food intake and sperm maturation

Physiology and metabolism are often sexually dimorphic, but the underlying mechanisms remain incompletely understood. Here, we use the intestine of Drosophila melanogaster to investigate how gut-derived signals contribute to sex differences in whole-body physiology. We find that carbohydrate handling is male-biased in a specific portion of the intestine. In contrast to known sexual dimorphisms in invertebrates, the sex differences in intestinal carbohydrate metabolism are extrinsically controlled by the adjacent male gonad, which activates JAK-STAT signalling in enterocytes within this intestinal portion. Sex reversal experiments establish roles for this malebiased intestinal metabolic state in controlling food intake and sperm production through gutderived citrate. Our work uncovers a male gonad-gut axis coupling diet and sperm production, and reveals that metabolic communication across organs is physiologically significant. The instructive role of citrate in inter-organ communication may be significant in more biological contexts than previously recognised

Genetic Predisposition to Chronic Lymphocytic Leukemia Is Mediated by a BMF Super-Enhancer Polymorphism

SummaryChronic lymphocytic leukemia (CLL) is an adult B cell malignancy. Genome-wide association studies show that variation at 15q15.1 influences CLL risk. We deciphered the causal variant at 15q15.1 and the mechanism by which it influences tumorigenesis. We imputed all possible genotypes across the locus and then mapped highly associated SNPs to areas of chromatin accessibility, evolutionary conservation, and transcription factor binding. SNP rs539846 C>A, the most highly associated variant (p = 1.42 × 10−13, odds ratio = 1.35), localizes to a super-enhancer defined by extensive histone H3 lysine 27 acetylation in intron 3 of B cell lymphoma 2 (BCL2)-modifying factor (BMF). The rs539846-A risk allele alters a conserved RELA-binding motif, disrupts RELA binding, and is associated with decreased BMF expression in CLL. These findings are consistent with rs539846 influencing CLL susceptibility through differential RELA binding, with direct modulation of BMF expression impacting on anti-apoptotic BCL2, a hallmark of oncogenic dependency in CLL