Selenium Supplementation during Puberty and Young Adulthood Mitigates Obesity-Induced Metabolic, Cellular and Epigenetic Alterations in Male Rat Physiology

Abstract

Selenium (Se) role in obesity is not clear. In addition, information on Se's role in male physiology, specifically in obesity, is scarce. We conducted this study to evaluate the efficacy of Se supplementation, specifically during puberty until young adulthood, against obesity-induced deregulation of metabolic, cellular, and epigenetic parameters in epididymal fat and/or sperm cells in a rat model. High-fat-diet consumption by male rats during puberty and young adulthood significantly increased body weight, adipocyte size, oxidative stress, deregulated expression of genes associated with inflammation (Adiponectin, IL-6, TNF-α), adipogenesis (CEBPα), estrogen biosynthesis (CYP19) and epigenetic processes in epididymal adipose tissue (Dnmt3a), as well as altered microRNA expression vital for spermatogenesis in sperm cells (miR-15b and miR-497). On the other hand, Se supplementation significantly decreased oxidative stress and mitigated these molecular/epigenetic alterations in epididymal adipose tissue or sperm cells. Our results indicate that selenium supplementation during puberty/young adulthood could improve male physiology in the context of obesity. In addition, it suggests that Se could potentially positively affect offspring health.

Keywords: epigenetics reprogramming; male physiology; obesity; selenium.

Figure 1

Representative photomicrographs of epididymal adipose tissue stained with hematoxylin-eosin. (A) CO group; (B) OB; (C) OBSe. All images are shown at ×100 magnification. Adipocyte sizes were larger (p = 0.0072) in OB group compared to CO group, while no differences (p > 0.05) were observed between OB and OBSe groups, according to chi-square test and Student’s t-test.

Figure 2

Testicular architecture. Representative photomicrograph of testicular tubules stained with hematoxylin-eosin. (A) CO group; (B) OB; (C) OBSe. All images are shown at ×10 magnification. No statistically significant difference (p > 0.05) among groups according to chi-square test and Student’s t-test.

Figure 3

Effects of high-fat obesogenic diet and Se supplementation on total cholesterol and fractions and triglycerides plasmatic levels. Data represent the mean ± SEM (n = 5/group). Statistically significant difference (p ≤ 0.05) compared to ^a CO or ^b OB group according to one-way ANOVA followed by Tukey’s multiple comparisons test.

Figure 4

Effect of high-fat obesogenic diet and Se supplementation on MDA levels in liver (A) and epididymal adipose (B) and hepatic antioxidant enzyme activities (CAT (C), SOD (D) and GPx (E)). Data represent the mean ± SEM (n = 5/group). Statistically significant difference (p ≤ 0.05) compared to ^a CO and ^b OB groups according to one-way ANOVA, followed by Tukey’s multiple comparisons test.

Figure 5

Effect of high-fat obesogenic diet and Se supplementation on gene expression in epididymal adipose tissue: (A) PPARy; (B) CEBPα; (C) CEBPβ; (D) Adiponectin; (E) IL-6; (F) TNFα; (G) CYP-19; (H) DNMT3A; (I) DNMT1. Data represent the mean ± SEM (n = 5/group). Statistically significant difference (p ≤ 0.05) compared to ^a CO and ^b OB groups according to one-way ANOVA, followed by Tukey’s multiple comparisons test.

Figure 5

Effect of high-fat obesogenic diet and Se supplementation on gene expression in epididymal adipose tissue: (A) PPARy; (B) CEBPα; (C) CEBPβ; (D) Adiponectin; (E) IL-6; (F) TNFα; (G) CYP-19; (H) DNMT3A; (I) DNMT1. Data represent the mean ± SEM (n = 5/group). Statistically significant difference (p ≤ 0.05) compared to ^a CO and ^b OB groups according to one-way ANOVA, followed by Tukey’s multiple comparisons test.

Figure 6

Effect of high-fat obesogenic diet and Se supplementation on sperm miRNA levels: (A) miR-15b; (B) miR-200c; (C) miR-497. Data represent the mean ± SEM (n = 7/group). Statistically significant difference (p ≤ 0.05) compared to ^a CO and ^b OB groups according to one-way ANOVA, followed by Tukey’s multiple comparisons test. Tendency of Statistically significant difference (p ≤ 0.07) compared to ^c CO according to one-way ANOVA, followed by Tukey’s multiple comparisons test.