Effect of Different High-Fat and Advanced Glycation End-Products Diets in Obesity and Diabetes-Prone C57BL/6 Mice on Sperm Function

Abstract

Background: We aimed to compare the effects of using high-fat (HF) and advanced glycation end-products (AGEs) containing dietsto induce obesity and diabetes on sperm function in mice.

Materials and methods: In this experimental study, twenty-five 4-week old C57BL/6 mice were divided into 5 groups and were fed with control, 45% HF, 60% HF, 45% AGEs-HF, or 60% AGEs-HF diet. After 28 weeks, fast blood sugar, glucose intolerance, insulin concentration, homeostatic model assessments (HOMA) for insulin resistance (IR) and HOMA for beta cells (HOMA beta) from systematic blood were assessed. In addition, body weight, morphometric characteristics of testes, sperm parameters, DNA damage (AO), protamine deficiency (CMAA3), and sperm membrane (DCFH-DA) and intracellular (BODIPY) lipid peroxidation were measured.

Results: Body mass and fasting blood sugar increased significantly in all experimental groups compared to the control group. Insulin concentration, glucose intolerance, HOMA IR, and HOMA beta were also increased significantly with higher levels of fat and AGEs in all four diets (P<0.05). The changes in the 60% HF-AGEs group, however, were more significant (P<0.001). Morphometric characteristics of the testis, sperm concentration, and sperm morphology in the diet groups did not significantly differ from the control group, while sperm motility and DNA damage in the 45%HF were significantly low. Although for protamine deficiency, both 60% HF-AGEs and 45% HF showed a significant increase compared to the control, the mean of sperm lipid in the 45% HF group and intracellular peroxidation in the 60% HF-AGEs group had the highest and the lowest increases, respectively.

Conclusion: Our results, interestingly, showed that isthe negative effects of a diet containing AGEs on examined parameters are lessthan those in HF diets. One possible reason is detoxification through the activation of the protective glyoxalase pathway asthe result of the chronic AGEs increase in the body.

Keywords: Advanced Glycosylation End Products; Diabetes Mellitus; High-Fat Diet; Reactive Oxygen Species; Sperm Parameters.

Fig.1

Sperm parameters of different studied groups after 28 weeks of feeding C57/BL6 mice with special diets. A. Sperm concentration (10⁶ /mL). B. Sperm motility (%). C. Total sperms with abnormal morphology (%). Data are expressed as means ± standard error of the mean. HF; High-fat diet, AGEs; Advanced glycation end-products, * ; P<0.05, and **; P<0.01.

Fig.2

Comparison of sperm function tests within groups. A. Sperm DNA damages as shown by acridine orange staining (%) and B. Sperm protamine deficiency indicated by chromomycin A3 staining (%) in different study groups after 28 weeks of feeding special diets. Oxidative stress of sperms in different study groups after 28 weeks of feeding special diets studied by C. BODIPY probe (%) to analyze the sperm lipid peroxidation, and D. dichlorofluorescein diacetate (DCFH-DA) staining (%) to analyze intracellular ROS. Data are expressed as means ± standard error of the mean. HF; High-fat diet, AGEs; Advanced glycation end-products, * ; P<0.05, **; P<0.01, and ***; P<0.001.

Fig.3

The schematic diagram of experimental results. All groups of diets show an increase in body weight more than the control group diet, although the 60% HF diet is less than the 45% HF, and AGE. HF diets (45% and 60%). Similarity, the assessment of metabolic tests (FBS, GTT, Insulin concentration, HOMA IR, HOMA beta) demonstrate similar results as body weight (g). Unlike sperm motility (%), sperm concentration (10⁶ / ml) and sperm morphology (%) do not show any significant difference among diet groups. While, the assessments of sperm DNA damage (%) showed an increase in 45% HF diet group compared to all the groups while percentage of sperm protamine deficiency demonstrate a highly negative effect in all diet groups compared to control diet group. Approximately, the assessments of sperm ROS [lipid peroxidation (%) and intracellular oxidation (%)] reveal an increase in all the groups compared to control group. HF; High-fat diet, AGE; Advanced glycation end-products, FBS; Fasting blood sugar, GTT; Glucose tolerance test, and HOMA IR; Homeostatic model assessment for insulin resistance