Possible protective effects of vanillin against stress-induced seminiferous tubule injury via modulation of Nrf2 and ZO1

Around 20% of the human population is distressed. Previous studies have looked into the relationship between restraint immobilization stress (IS) and sexual behavior in male rats. The current study aimed to provide a brief explanation of the mechanisms that generated testicular injury with chronic IS and an attempt to evaluate the mechanisms and effects of vanillin as a novel protective agent. Forty-eight adult male albino rats were divided into six groups: control, vanillin-treated, chronic 2-h IS, 2-h stressed-vanillin-treated, chronic 6-h IS, and 6-h stressed-vanillin treated. The rats were sacrificed, and blood samples were collected for biochemical study. The testes were processed for biochemical and histological study, as well as histological Johnsen score. The results showed that prolonged IS increased both corticosterone and TNF-α levels as well as decreased testosterone, luteinizing hormone, catalase, and Nrf2 levels. This effect was more pronounced after 6 h of IS compared to 2 h. It also induced various testicular injuries with weak ZO-1 and CD34 immunoreactions. On the contrary, vanillin improved all mentioned biochemical and histological alternations induced by stress. Additionally, computational molecular docking analyses were conducted on the compound vanillin within the active site of Zona Occludens-1 (PDB ID: 2JWE). The results demonstrated remarkable docking scores and binding affinity, corroborating its potential protective efficacy. It could be concluded that vanillin is a promising treatment alternative for protecting testicular tissue from the harmful effects of IS via its antioxidant and anti-inflammatory properties.

Ghrelin and the Control of Energy Balance in Females

Ghrelin is considered one of the most potent orexigenic peptide hormones and one that promotes homeostatic and hedonic food intake. Research on ghrelin, however, has been conducted predominantly in males and particularly in male rodents. In female mammals the control of energy metabolism is complex and it involves the interaction between ovarian hormones like estrogen and progesterone, and metabolic hormones. In females, the role that ghrelin plays in promoting feeding and how this is impacted by ovarian hormones is not well understood. Basal ghrelin levels are higher in females than in males, and ghrelin sensitivity changes across the estrus cycle. Yet, responses to ghrelin are lower in female and seem dependent on circulating levels of ovarian hormones. In this review we discuss the role that ghrelin plays in regulating homeostatic and hedonic food intake in females, and how the effects of ghrelin interact with those of ovarian hormones to regulate feeding and energy balance.

High Hydrostatic Pressure Extract of Ginger Exerts Antistress Effects in Immobilization-Stressed Rats

Stress contributes to physiological changes such as weight loss and hormonal imbalances. The aim of the present study was to investigate antistress effects of high hydrostatic pressure extract of ginger (HPG) in immobilization-stressed rats. Male Sprague-Dawley rats (n = 24) were divided into three groups as follows: control (C), immobilization stress (2 h daily, for 2 weeks) (S), and immobilization stress (2 h daily, for 2 weeks) plus oral administration of HPG (150 mg/kg body weight/day) (S+G). Immobilization stress reduced the body weight gain and thymus weight by 50.2% and 31.3%, respectively, compared to the control group. The levels of serum aspartate transaminase, alanine transaminase, and corticosterone were significantly higher in the stress group, compared to the control group. Moreover, immobilization stress elevated the mRNA levels of tyrosine hydroxylase (Th), dopamine beta-hydroxylase (Dbh), and cytochrome P450 side-chain cleavage (P450scc), which are related to catecholamine and corticosterone synthesis in the adrenal gland. HPG administration also increased the body weight gain and thymus weight by 12.7% and 16.6%, respectively, compared to the stress group. Furthermore, the mRNA levels of Th, Dbh, phenylethanolamine-N-methyltransferase, and P450scc were elevated by the HPG treatment when compared to the stress group. These results suggest that HPG would have antistress effects partially via the reversal of stress-induced physiological changes and suppression of mRNA expression of genes related to corticosterone and catecholamine synthetic enzymes.