Low-protein diet in puberty impairs testosterone output and energy metabolism in male rats

Abstract

We examined the long-term effects of protein restriction during puberty on the function of hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes in male rats. Male Wistar rats from the age of 30 to 60 days were fed a low-protein diet (4%, LP). A normal-protein diet (20.5%) was reintroduced to rats from the age of 60 to 120 days. Control rats were fed a normal-protein diet throughout life (NP). Rats of 60 or 120 days old were killed. Food consumption, body weight, visceral fat deposits, lipid profile, glycemia, insulinemia, corticosteronemia, adrenocorticotropic hormone (ACTH), testosteronemia and leptinemia were evaluated. Glucose-insulin homeostasis, pancreatic-islet insulinotropic response, testosterone production and hypothalamic protein expression of the androgen receptor (AR), glucocorticoid receptor (GR) and leptin signaling pathway were also determined. LP rats were hypophagic, leaner, hypoglycemic, hypoinsulinemic and hypoleptinemic at the age of 60 days ( < 0.05). These rats exhibited hyperactivity of the HPA axis, hypoactivity of the HPG axis and a weak insulinotropic response ( < 0.01). LP rats at the age of 120 days were hyperphagic and exhibited higher visceral fat accumulation, hyperleptinemia and dyslipidemia; lower blood ACTH, testosterone and testosterone release; and reduced hypothalamic expression of AR, GR and SOCS3, with a higher pSTAT3/STAT3 ratio ( < 0.05). Glucose-insulin homeostasis was disrupted and associated with hyperglycemia, hyperinsulinemia and increased insulinotropic response of the pancreatic islets. The cholinergic and glucose pancreatic-islet responses were small in 60-day-old LP rats but increased in 120-day-old LP rats. The hyperactivity of the HPA axis and the suppression of the HPG axis caused by protein restriction at puberty contributed to energy and metabolic disorders as long-term consequences.

Protein restriction during puberty alters nutritional parameters and affects ovarian and uterine histomorphometry in adulthood in rats

“…25 Protein restriction at puberty led to a reduction in body weight, visceral fat, feed efficiency and protein consumption, while food and energy consumption was higher in animals that received a low-protein diet. Similar results were observed by Oliveira et al, 26 who demonstrated that consumption of a low-protein diet at puberty is associated with reduced body weight, consumption of protein and visceral fat; however, they observed a reduction in food and energy intake, diverging from our present findings. Previous studies by França et al 27 and Dos Santos et al 28 also reported an increase in food and energy intake and lower body weight, with a significant increase in body fat content.…”

Disadvantageous Socioeconomic Position at Specific Life Periods May Contribute to Prostate Cancer Risk and Aggressiveness

“…The effect of disadvantageous SEP in childhood/adolescence suggested by our findings could be attributable to several factors. For example, a poor diet can disturb the pre-adulthood hormonal milieu ( 52 ) at the time when the prostate develops most quickly. This is reflected in lower height ( 53 ) and childhood obesity ( 54 ).…”

The effect of dietary protein intake on factors associated with male infertility: A systematic literature review and meta-analysis of animal clinical trials in rats

“…Studies have shown that the amount of protein in the diet affects the hypothalamic-pituitary-testis axis and suboptimal quantity diminishes male fertility potential in both animals and humans (De Oliveira et al, 2018;Glass et al, 1982;Khorram et al, 2015;Leonhardt et al, 2003;Malta et al, 2014). The detrimental effect of protein malnutrition on male reproductive function have been reviewed by several studies (Bindari et al, 2013;Kemp and Den Hartog, 1989;McShane et al, 1993;Martin et al, 2010;Salas-Huetos et al, 2017).…”