Integrated Multiomics Analyses Reveal Molecular Insights into How Intermittent Fasting Ameliorates Obesity and Increases Fertility in Male Mice

<b>Background:</b> Intermittent fasting (IF) has been increasingly recognized for its potential to mitigate obesity and diabetes. However, it remains unclear whether IF can alleviate metabolic disorder-induced male infertility. The aim of this study was to investigate the potential of IF to improve fertility outcomes in obese mice. <b>Methods:</b> Eight-week-old C57BL/6J mice were fed a high-fat diet (HFD) for 24 weeks to induce obesity, followed by alternate-day fasting for 6 weeks. We assessed obesity-related metabolic changes and fertility issues postintervention. Comprehensive metabolomic and transcriptomic analyses of serum and testicular samples were used to identify significant metabolic pathway modifications attributable to IF. <b>Results:</b> IF effectively alleviated obesity-induced male infertility, demonstrating significant attenuation of body weight gain and restoration of testicular morphology. IF normalized hypogonadism-associated testosterone depletion and improved sperm parameters. Testis multi-omics integration revealed IF-mediated reprogramming of testicular purine metabolism, coupled with coordinated regulation of glycolipid metabolism and inflammatory-immune homeostasis. Reproductive competence was enhanced as evidenced by statistically elevated successful mating rates and embryonic developmental progression. Serum metabolomics further identified metabolites involved in amino acid metabolism, glycolipid metabolism, and inflammation (e.g., methionine, BCAA, glutathione, and spermidine) may serve as potential targets for treating obesity-related metabolic disorders. Additionally, multidimensional analysis highlighted the crucial role of allantoin in alleviating obesity and related reproductive dysfunction. <b>Conclusions:</b> IF not only resolves obesity-induced metabolic issues but also alleviates male infertility by regulating bioactive metabolites and gene expression linked to glycolipid metabolism, energy homeostasis, and immune responses in the testis. Our study provides a theoretical basis for IF as a clinical treatment for obesity-induced male infertility.