Abstract
Polyphenols have antioxidant and anti-inflammatory properties and maintain the immune system in balance; therefore, the aim of the study was to investigate the effect of polyphenols present in pomegranate peel extract on the spleens of rats with metabolic syndrome. The study objects were adult male Zucker Diabetic Fatty (ZDF-Leprfa/Crl, fa/fa) rats. The rats were divided into a control group (MetS) consisting of rats with metabolic syndrome and four study groups consisting of rats with metabolic syndrome (MetS + 100 mg and MetS + 200 mg) or healthy animals (H + 100 mg and H + 200 mg) receiving polyphenol extract at a dose of 100 mg or 200 mg/kg, respectively. Concentrations of IL-6, NF-κB, NFATc1, Cyt-C, TNFα, MMP-2, ROS/RNS, and MDA were measured; the activities of GPX, SOD, CAT, MMP-2, and MMP-9 were assessed; and the expression of the BAX and BCL-2 genes was evaluated in homogenized spleens. In conclusion, pomegranate extract may lead to an increase in catalase and glutathione peroxidase activity. Additionally, it may have a reducing effect on the ROS/RNS level, leading to a reduction in the activity of SOD in the MetS groups with PPE administration. Moreover, the BCL-2 gene showed lower expression in the MetS + 100 mg group compared to the H + 100 mg group, indicating that the balance between pro- and antiapoptotic factors of the BCL-2 family may be disrupted by the metabolic syndrome promoting the proapoptotic pathway.