Stress, Sex, and Sugar: Glucocorticoids and Sex-Steroid Crosstalk in the Sex-Specific Misprogramming of Metabolism

Early-life exposures to environmental insults can misprogram development and increase metabolic disease risk in a sex-dependent manner by mechanisms that remain poorly characterized. Modifiable factors of increasing public health relevance, such as diet, psychological stress, and endocrine-disrupting chemicals, can affect glucocorticoid receptor signaling during gestation and lead to sex-specific postnatal metabolic derangements. Evidence from humans and animal studies indicate that glucocorticoids crosstalk with sex steroids by several mechanisms in multiple tissues and can affect sex-steroid-dependent developmental processes. Nonetheless, glucocorticoid sex-steroid crosstalk has not been considered in the glucocorticoid-induced misprogramming of metabolism. Herein we review what is known about the mechanisms by which glucocorticoids crosstalk with estrogen, androgen, and progestogen action. We propose that glucocorticoid sex-steroid crosstalk is an understudied mechanism of action that requires consideration when examining the developmental misprogramming of metabolism, especially when assessing sex-specific outcomes.

The changes in semen quality, arginase activity and nitric oxide level in dexamethasone-treated rams

This study was made to investigate the effects of intramuscular administrations of dexamethasone on seminal plasma nitric oxide levels and arginase activity, and some spermatological parameters in rams. Ten Akkaraman rams weighing 50-60 kg and 2 years old were used as material in this study. The study was performed during the breeding season (September-November) for rams. The semen was collected by artificial vagina at 1st, 4th, 24th, 48th, 72nd and 96th hours for control group before dexamethasone administration. For treatment group, 0.25 mg/kg dexamethasone was administered and semen was collected at the time points described for control group. Spermatological characteristics of semen samples (semen volume, pH, sperm motility, density and abnormal sperm rate), seminal plasma arginase enzyme activities and nitric oxide levels were determined. It was determined that the administration of dexamethasone was detected to decrease seminal plasma arginase activity (p < .05 and .01) and nitric oxide level (p < .05), semen volume (p < .05 and .01), mass activity (p < .05 and .01), sperm density (p < .05) and sperm motility (p < .05 and .01), and to increase abnormal sperm rate (p < .05 and .01). In conclusion, dexamethasone is not recommended to be used during the breeding season as it damages the sperm quality of the rams.

Adverse effect of dexamethasone on development of the fetal rat ovary

Dexamethasone (Dx) is often used in obstetric practice to promote fetal lung maturation and to prevent respiratory distress syndrome when the risk of preterm delivery persists. This therapy enables survival of the newborn, but also is associated with deleterious effects on the offspring, such as reproductive disorders. The aim of this study was to determine specifically whether prenatal exposure to Dx disturbs the physiological balance between proliferation and apoptosis of germinative cells (GC) in the ovary of 19- and 21-day-old fetuses and thus induces developmental programming of the female reproductive system. Pregnant Wistar rats (n = 10/group), separated into control (vehicle) and Dx-treated (0.5 mg/kg body mass) groups, received injections on gestational days 16, 17, and 18. Exposure to Dx lowered the volume of the fetal ovary by 30% (P < 0.05) in 21-day-old fetuses, as well as the total number of GC in the ovary by 21% (P < 0.05). When compared to the controls, in Dx-exposed fetuses, the total number of PCNA-positive GC was 27% lower at 19 days and 71% lower at 21 days old (P < 0.05), while total numbers of caspase-3-positive GC were 2.3-fold and 34% higher, respectively (P < 0.05). Our results demonstrate that prenatal exposure to Dx diminished proliferation but increased the rate of germinative cell apoptosis, with consequently reduced total germinative cell number and ovary volume. Impairment of fetal oogenesis and fewer GC in the fetal ovary compromise the oogonial stock and thus may constitute a risk of female fertility.