Robusta peaberry coffee attenuates inflammation, regulates apoptosis, and improves testicular cell integrity in diabetic rats

Background: Diabetes mellitus (DM) is a chronic metabolic disorder that can impair male reproductive function through oxidative stress, inflammation, and apoptosis. Robusta peaberry coffee contains chlorogenic acid (CGA) and other polyphenols with antioxidant and anti-inflammatory properties that may protect against diabetes-related testicular injury. Objectives: This study aimed to evaluate the effects of robusta peaberry coffee on inflammation, apoptosis-related markers, reproductive hormones, and testicular cell integrity in streptozotocin (STZ)-induced diabetic male rats. Materials and methods: Male Wistar rats (N=28) were randomly assigned to four groups: diabetic control (KN), diabetic rats treated with metformin (KP; 500 mg/kg body weight [BW]/day), diabetic rats treated with robusta peaberry coffee at 100 mg/kg BW/day (P1), and diabetic rats treated with robusta peaberry coffee at 200 mg/kg BW/day (P2). Experimental diabetic rats were induced by a single intraperitoneal injection of STZ (40 mg/kg BW). Rats with fasting blood glucose (FBG) ≥200 mg/dL were included. Treatments were administered orally for 14 consecutive days. At the end of the intervention, serum nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), caspase-3, testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and the numbers of Sertoli and Leydig cells were evaluated. Results: Testosterone, LH, FSH, Sertoli cell count, and Leydig cell count were significantly lower in the KN group than in the KP, P1, and P2 groups (p<0.05). In contrast, NO, TNF-α, IL-1β, and caspase-3 were significantly higher in the KN group than in the treatment groups (p<0.05). The P2 group showed the greatest improvement, with higher reproductive hormone levels and testicular cell counts and lower inflammatory and apoptosis-related markers than P1 (p<0.05). Conclusion: Robusta peaberry coffee attenuates inflammation, modulates apoptosis-related responses, and improves testicular cell integrity in diabetic rats. These findings suggest that robusta peaberry coffee may serve as a promising complementary natural intervention for mitigating diabetesinduced male reproductive dysfunction.