Role of Irisin Administration in Modulating Testicular Function in Adult Obese Albino Rats

Abstract

Background: Irisin, exercise-induced myokine, is known to improve obesity-induced metabolic disturbances by enhancing thermogenesis and increasing energy expenditure. Recent studies have reported that irisin promoted cell proliferation and protected cells from apoptosis. However, the effects of irisin on testicular function in obese rats is still to be investigated. Aim of the Study: This study was designed to explore the probable effects of irisin treatment on modulating the adverse effects of obesity on testicular functions with a trial to clarify some of the possible underlying mechanisms. Material and Methods: Thirty adult male wistar albino rats (200±30g) were divided equally into 3 groups, group (I): Saline-vehicle treated normal fed group, group (II): Salinevehicle treated rats were fed a High Fat Diet (HFD) for 10 weeks. Group (III): Irisin treated HFD-fed rats for 10 weeks and irisin was injected subcutaneously (150µ l daily for 4 weeks). Rats were weighed and serum levels of glucose, insulin, lipid profile, FSH, LH, estradiol & testosterone levels, epididymal sperm count and motility, testicular Malondialdhyde (MDA) level, Superoxide Dismutase (SOD), Catalase (CAT), Glutathione Peroxidase (GP X) activities, testicular and epidydimal fat weights were estimated. Testicular histopathological study was done as well. Results: There was a significant increase in the Body Mass Index (BMI) together with deterioration of metabolic, gonadal functions and testicular oxidant/antio-oxidant system in group (II), while exogenous irisin administration in group (III) resulted in: Significant decrease in BMI, insulin resistance with improvement in lipid profile, significant increase in serum FSH, LH & testosterone, sperm count and motility in male rats. Together with marked improvement in the testicular histoarchitecture. Additionally, there was a significant increase in testicular SOD, CAT & GP X activities. However, it significantly decreased testicular MDA level. Conclusions: It could be suggested that irisin has a potential positive role against obesity-induced testicular dysfunction, which may be due to its role in maintenance of glucose & insulin homeostasis, its antioxidant properties and/ or maintenance of gonadal hormonal function via indirect and/or direct effects on the gonads.

Studying the Role of Irisin, Chemerin and Some Other Hormonal Levels in Obese, Diabetic (type II) and Sub-Fertile Men

“…[35] Treatment with irisin in obese male rats enhanced the FSH , LH and testosterone hormone levels in blood resulting in promotion spermatogenesis and sperm properties such as sperm count and motility. [36] 0 ) in sub-fertility group (769.85 ± 2.20 pg/ml), in obesity group (680.01 ± 2.80 pg/ml) and in diabetic group (532.25 ± 4.19 pg/ml) in comparison with the control (472.90 ± 3.61 pg/ml) (Figure 2). The reasons of high level of chemerin might be attributed to lipoprotein chemerin's secretion mainly by adipose tissue and by the adipocyte's cells according to a high BMI and / or a high insulin resistance and / or the inhibition of prolactin hormone on gonadotropin (FSH, LH) thereby testosterone production, leading to an increase in chemerin secretion in obesity, diabetic and sub-fertility groups.…”

Irisin, Energy Homeostasis and Male Reproduction

“…Irisin-mediated upregulation of the expression of Elov13, Cox7a, and Otop1 genes and increased energy expenditure maintain energy homeostasis (Boström et al, 2012). It has been shown that irisin administration in obese male rats could downregulate IR, decrease BMI, enhance the serum levels of FSH and LH, increase testosterone levels thereby resulting in improved spermatogenesis and increased sperm parameters, namely sperm count and motility (Nanees and Reham, 2018). Moreover, in vitro study demonstrated the possible role of irisin in spermatogenesis owing to increased irisin expressions in Sertoli cells and undifferentiated spermatogonia transcripts in organotypic primate testicular tissue culture (Wahab et al, 2020).…”

“…Despite its essential contribution in energy homeostasis, its detailed physiological actions on reproduction are yet to be explored. Few studies on animals indicate positive impact of irisin upon male fertility (Nanees and Reham, 2018;Tekin et al, 2019;Luo et al, 2021). Thus, it may be assumed that irisin, via reversing obesity, also ameliorates the obesity-induced disruptions in male fertility.…”