Effects of Undernutrition on Serum and Testicular Testosterone Levels and Sexual Function in Adult Rats

Abstract

The aim of this study was to evaluate testosterone concentrations, sexual behavior, and androgen receptor protein level in the testes of rats submitted to protein- and energy-restricted diets during 30 days. Adult male Wistar rats were assigned to one of the following groups: (C) control, diet with 23% of protein; (PR) protein-restricted, diet with 8% of protein; (ER) energy-restricted, diet with 23% of protein in restricted quantities. Mount number, ejaculation latencies and copulatory efficiency were evaluated to determine sexual behavior. At the end of the experiment, the animals were sacrificed to determine serum and testicular testosterone concentrations as well as testicular androgen receptor protein level. Compared to the C group, the ER group presented a significant decrease in body (36%), testis (20%) and epididymis (14%) weights in serum (78%) and testicular (68%) testosterone concentrations as well as in copulatory efficiency (26%). On the other hand, the ER group presented a significant increase in mount number (114%) and ejaculatory latency (62%). The androgen receptor protein levels were significantly reduced in both PR and ER groups (41% and 74%, respectively). This is the first paper to demonstrate that the effect of undernutrition on reproduction is not related to reduced protein intake but caloric restriction. Also, in caloric restriction, there is a relationship between sex behavior, androgen receptors, and testosterone concentration.

Mutant phenotype analysis suggests potential roles for C-type natriuretic peptide receptor (NPR-B) in male mouse fertility

“…Why the Npr2 cn-2J/cn-2J mice do not suffer from these GI problems is not clear, but may depend on the respective genetic backgrounds. These conclusions about the importance of nutrition are consistent with reports on the role of nutrition in growth and development of the reproductive system [16]; moreover, dietary restriction is known to impact negatively on testicular volume, weight and function [18,19]. …”

Protective effects of pomegranate (Punica granatum) juice on testes against carbon tetrachloride intoxication in rats

“…Secretion of testosterone is probably impaired due to excessive oxidative stress and the degeneration of Leydig cells [46]. Metabolites of testosterone reciprocally depress FSH and LH secretion [47].…”

Catch‐up fat in male adults induces low testosterone and consequently promotes metabolic abnormalities and cognitive impairment

“…It is reported that caloric restriction might result in central hypogonadism 29 and induce significant decreases in testis and epididymis weights, serum and testicular testosterone concentrations as well as AR protein levels in the testis of rats. 30 That refeeding after the caloric restriction is able to elevate the testosterone level mildly to some extent but not recover completely and promptly, 31 might be an important reason for the inappropriate normal LH levels and reduced testosterone levels in male CUFA humans and rats in the present study. 32,33 Additionally, neuronal insulin receptor knockout mice become insulin resistant and also have a reduction in LH concentrations and low testosterone concentrations, 34 implying that the IR of the central system during refeeding after caloric restriction might also be a contribution to hypogonadotropism in male CUFA rats.…”