Effects of Aerobic Training on Sex Hormones in A Cuprizone Rat Model of Multiple Sclerosis

Abstract

Background: Central nervous system damage in multiple sclerosis (MS) leads to severe physical disability and neurological defects. Sexual dysfunction and infertility in patients with MS have often been neglected in previous studies. Aerobic exercise is suggested to improve circulating testosterone levels and sexual function. Therefore, the purpose of this study was to investigate the effect of aerobic exercise on sex hormone levels in a cuprizone rat model of MS.

Materials and methods: In this experimental study, 30 male rats (aged 70 days, 154.55 ± 18.1 g) were randomly divided into five groups: MS, exercise-MS (EX-MS), MS-EX, EX-MS-EX, and normal control (control). MS was induced by feeding cuprizone pellets (0.2%) to the rats for six weeks. The exercise groups performed an aerobic exercise protocol on a treadmill five days/week for six weeks before and during the induction of the MS model. Serum testosterone, follicle stimulating hormone (FSH), and luteinising hormone (LH) levels were measured using the ELISA method with standard kits (ZellBio Germany). Luxol fast blue staining (LFB) of the corpora collosa were performed.

Results: The results showed a significant decrease in the serum levels of testosterone, FSH, and LH in the MS groups compared to the control group (P<0.05). There was a significant increase in the serum levels of testosterone, FSH, and LH in the EX-MS-EX, and EX-MS groups compared to the MS group (P<0.05).

Conclusion: Aerobic exercise could improve the level of sex hormones in the cuprizone rat model of MS and may be used to attenuate sexual dysfunction in patients with MS.

Keywords: Aerobic Exercise; Follicle Stimulating Hormone; Luteinising Hormone; Multiple Sclerosis; Testosterone.

Fig 1

Experimental research design. EX-MS-EX group performed the exercise protocol before and during the inducement of MS; the EX-MS group performed the exercise protocol before the inducement of MS; the MS-EX group that performed the exercise protocol during the inducement of MS. MS group was fed a 0.2% cuprizone diet. The control group received the regular diet. MS; Multiple sclerosis and EX; Exercise.

Fig 2

The ANOVA test was used to analyse the serum testosterone levels between the experimental groups. The data are reported as mean ± SD. Various letters above the bars indicate significant differences. MS; Multiple sclerosis and EX; Exercise.

Fig 3

ANOVA test was used to analyse serum FSH levels between the experimental groups. The data are reported as mean ± SD. Various letters above the bars indicate significant differences. FSH; Follicle stimulating hormone, MS; Multiple sclerosis, and EX; Exercise.

Fig 4

ANOVA test was used to analyse serum LH levels between the experimental groups. The data are reported as mean ± SD. Various letters above the bars indicate significant differences. LH; Luteinising hormone, MS; Multiple sclerosis, and EX; Exercise.

Fig 5

Luxol fast blue staining and demyelination volume analysis. A. LFB. The blue staining indicates the myelin sheaths. B. Demyelination in the experimental groups. Various letters above the bars indicate significant differences. There is significantly higher demyelination in the corpora callosa in the MS groups compared to the control group. Data are reported as mean ± SD. LFB; Luxol fast blue, MS; Multiple sclerosis, and EX; Exercise.