Lycopene Ameliorated Oxidative Stress and Inflammation in Type 2 Diabetic Rats

We aim to study the antioxidative and anti-inflammatory effects of lycopene on type 2 diabetes mellitus (T2DM) rats, anticipating a complementary strategy for the prevention of long-term complications of T2DM. In this study, rats with streptozotocin-induced diabetes were divided into four groups, receiving a 10-week lycopene intervention: DM, DM + low dose of lycopene (L), DM + medium dose of lycopene (M), and DM + high dose of lycopene (H) group with 0, 5, 10, and 15 mg/kg BW lycopene, respectively. At the end of intervention, fasted blood glucose (FBG) level, oxidative stress indicators, including glycosylated hemoglobin (GHb), glycosylated low-density lipoprotein, oxidized low-density lipoprotein (ox-LDL). and malondialdehyde (MDA), as well as antioxidants, that is, catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx), and inflammatory factors like tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP) were determined. The results indicated that oxidative stress and inflammatory factors were elevated in DM rats. Lycopene intervention decreased the FBG level in DM rats compared with the untreated ones. It revealed a dose-dependent effect on decreasing serum oxidative stress biomarkers, including GHb, ox-LDL, and MDA. Inflammatory factors (TNF-α and CRP) in DM rats were also decreased by lycopene intervention. Total antioxidative capacity as well as the activities of antioxidants in DM rats including CAT, SOD, and GPx were increased after lycopene intervention. We conclude that lycopene protects against diabetic progression and prevents further complications of diabetic rats through ameliorating oxidative stress and inflammation, as well as improving the systemic antioxidative capacity. PRACTICAL APPLICATION: According to our study, lycopene intakes at experimental dosages appear to have beneficial effects on ameliorating oxidative stress and inflammation in type 2 diabetes mellitus (T2DM) rats, suggesting that lycopene might help improving T2DM progression when its daily intake is up to about 0.79 mg/kg BW in humans, which approximately equals to 5 mg/kg BW in rats. However, more clinical trials are needed to provide a more reliable and convincing conclusion in humans.