Correcting imbalance of sex hormones by a phosphodiesterase 5 inhibitor improves copulatory dysfunction in male rats with type 2 diabetes

Abstract

IntroductionSexual dysfunction is a common complication in men with type 2 diabetes and is often refractory to treatment. This study investigated the long-term influence of the phosphodiesterase 5 inhibitor (PDE5I) tadalafil on the level of sex hormones and sexual function in male Otsuka Long-Evans Tokushima Fatty (OLETF) rats as an animal model of spontaneous type 2 diabetes.Research design and methodsWe treated 36-week-old male OLETF and non-diabetic Long-Evans Tokushima Otsuka (LETO) rats with oral tadalafil (100 µg/kg/day) for 12 weeks; sham groups received vehicle for 12 weeks. Before and after tadalafil treatment, serum levels of total and free testosterone, estradiol, luteinizing hormone (LH), follicle-stimulating hormone and proinflammatory cytokines were compared among four treatment groups. Copulatory function was examined by matching each rat to an estrous female. After completion of the experiment, total fat mass in the abdomen was measured.ResultsTestosterone levels were significantly lower in OLETF versus LETO rats at 36 weeks. After 12 weeks of tadalafil treatment, levels of testosterone were significantly increased both in OLETF-tadalafil and LETO-tadalafil groups versus vehicle groups. Tadalafil decreased estradiol levels both in OLETF and LETO rats. Furthermore, tadalafil increased serum LH levels with a reduction of proinflammatory cytokines. Total fat mass was significantly lower in the OLETF-tadalafil group versus the OLETF-vehicle group. A significant suppression of copulatory behavior, that is, elongation of intromission latency was found in OLETF rats. However, tadalafil treatment for 12 weeks shortened the intromission latency.ConclusionOur results indicate that tadalafil treatment might improve copulatory disorder in the type 2 diabetic model via improvement of an imbalance in sex hormones and an increase in LH levels.

Application of hydrophilic polymers for the preparation of tadalafil solid dispersions: micromeritics properties, release and erectile dysfunction studies in male rats

“…Improvement in the sexual behavior of the treated (TK188) in male rats expressed potential aphrodisiac action. The improved sexual desire could be due to the stimulation of TFL to increase testosterone hormone, as reported by Itoga et al (2020) . Testosterone is a steroidal hormone secreted from the testes, which assists in sexual function and desires.…”

Effect of Asthma on Erectile Dysfunction in Rats as Determined by Biological Network Analysis

“…All rats were acclimatized in these conditions for 7 days with deionized water and solid feed. Before experiments, we confirmed that the rats exhibited normal sexual function by a mating behavior test and a noncontact penile erection test [ 7 ].…”

Potential mechanism of Achyranthis bidentatae radix plus semen vaccariae granules in the treatment of diabetes mellitus-induced erectile dysfunction in rats utilizing combined experimental model and network pharmacology

“…Before experimentation, the rats were shown to have a normal sexual function by mating with females (Itoga et al. 2020 ). The study protocol was approved (authorization number: 17–27) by the animal ethics committee of Beijing University of Traditional Chinese Medicine (Beijing, China).…”