Effect of Aronia melanocarpa fruit juice on the antioxidant defense system in rats with diet-induced metabolic syndrome

INTRODUCTION: The role of oxidative stress in the development of metabolic syndrome (MS) has been well established. Aronia melanocarpa fruits are very rich in polyphenols, which possess an antioxidant effect. AIM: The current study aimed to evaluate the effect of Aronia melanocarpa fruit juice (AMFJ) on the antioxidant defense system in rats with diet-induced MS. MATERIALS AND METHODS: Fifty male Wistar rats were allocated into 5 groups: control, MS, MS + AMFJ 2.5 , MS + AMFJ 5 and MS + AMFJ 10. For 10 weeks,the control group received regular diet and the other groups—high-fat high-fructose diet (HFHF). During this period, the control group and MS group were treated daily orally with 10 mL/kg distilled water and the other groups—with increasing volume (2.5 mL/kg, 5 mL/kg, and 10 mL/kg) of AMFJ. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured in the serum using commercial colorimetric kits. RESULTS: A significantly higher SOD level was observed in MS group (0.0069 ± 0.0007 U/mL) compared to the control group (0.0051 ± 0.0003 U/mL) (p<0.01). AMFJ treatment returned the level of SOD to the control values, with the effect being significant in MS + AMFJ 2.5 (0.0053 ± 0.0003 U/mL)and MS + AMFJ 5 (0.0053±0.0003 U/mL) groups (p<0.05 vs. MS). No significant difference was detected in the activity of GPx in all groups. CONCLUSION: HFHF diet-induced MS might be associated with superoxide production and compensatory activation of SOD. Due to its antioxidant properties, AMFJ counteracted these processes in the treated groups. Neither the HFHF diet, nor the AMFJ treatment affected the activity of GPx.