BackgroundDiet is the most important environmental factor but consumption of high calorie diet leads to obesity which contributes to the development of various diseases, mainly leads to testicular dysfunction and infertility in males. It was reported that traditional medicinal plant extracts showed preventive and ameliorative effect on the testis, spermatogenesis and also fertility in rats fed on high fat diet. With this context, we set out to see whether an aqueous extract of Syzygium paniculatum fruit may help restore normal function to male rat testes that had become dysfunctional. PurposeThe goal of our research was to determine preventive functions of Syzygium paniculatum against testicular dysfunction caused by a high fat diet induced obesity. Study designAll rats were grouped into three of six rats each (n = 6), Group 1-Control rats (C); Group 2-HFD obese rats (Ob C); Group 3-HFD fed obese rats treated with 100 mg/kg bw/day of AESPF. MethodsA high fat diet rat model was established to examine the effects of Syzygium paniculatum. Eighteen Albino Wister rats (n = 6) divided into three groups, which was control group, HFD group and HFD+ AESPF treated group. All rat groups had a 17 weeks treatment period, and their physical, biochemical, testicular, and cytotoxic effects were assessed along with spermatogenic marker for cellular apoptosis (Bax, Cleaved caspase 3, Caspase-3), cell proliferation (PCNA), cell survival (Bcl2), testicular inflammatory pathway regulators (TNF-α, NF-B, IL-6) and peroxisome proliferator activated receptor (PPAR) were evaluated by western blotting. The protective effects of S. Paniculatum on testes were evaluated by using histopathological examination. ResultsThe obese rats which given an HFD showed a substantial rise in their obesity index, aberrant hormone levels, and sperm counts along with the elevated expressions of inflammatory and apoptotic markers in the testis. Treatment with AESPF for 17 weeks improved testicular function, as measured by increased spermatogenesis and semen quality, lower expression of apoptotic and inflammatory proteins in the testes, and an increase in testosterone level and antioxidant capacity. Histopathological results corroborate the enhanced testicular relative weight and histological picture seen after AESPF treatment for 17 weeks. According to our findings, the metabolic and reproductive systems were dysfunctional after HFD intake, however AESPF restored normalcy. ConclusionThe administration of the aqueous extract of Syzygium paniculatum fruit (AESPF) reduced HFD induced spermatogenesis dysfunction and apoptosis. Obesity-related testicular dysfunction in men might be treated with Syzygium paniculatum fruit as a new therapeutic medication.