Effect of lycopene administration on plasma glucose, oxidative stress and body weight in streptozotocin diabetic rats

To evaluate the role of lycopene, a carotenoid antioxidant, on streptozotocin (STZ)-induced diabetic rats, 12 female rats received a single intraperitonial injection of STZ at a dose of 45 mg/kg body weight of which 6 were given 10 mg/kg lycopene orally (test group) once daily for 21 days. The administration of STZ caused a significant increase in plasma glucose and decrease in body weight. The supplementation of lycopene significantly reduced diabetic plasma glucose level by 25% and prevented body weight loss starting from 14(th) day of lycopene administration. Although tissue lipid peroxidation and nitric oxide (NO) levels were unchanged, lycopene administration significantly reduced diabetes-elevated lipid peroxidation and NO in plasma. It was concluded that lycopene supplementation may be valuable for correcting hyperglycemia and preventing diabetic complications caused by lipid peroxidation and free radicals.