rebaudioside-a and Reperfusion-Injury

This project aimed to examine Stevia rebaudiana aqueous extract protective effects on testicular ischaemia/reperfusion injury of rats. Forty rats were randomly divided into five groups: (1) sham group, (2) torsion/detorsion group, (3 and 4) low and high doses treatment groups received S. rebaudiana extract intraperitoneally 30 min before detorsion by 500 and 1,000 mg/kg respectively, and (5) healthy group received the extract by 1,000 mg/kg. In this study, left testes were rotated 2 hr, reperfusion period took long 5 hr, and then orchiectomy was performed. Histopathological and biochemical evaluations of testicular tissue samples were performed. Histopathologically, sham and healthy groups exhibited normal seminiferous tubules. Germinal cell necrosis, interstitial oedema, haemorrhage and congestion were seen in torsion/detorsion group. Testicular tissues of both treatment groups revealed lower histopathological alterations. Significant higher malondialdehyde level was observed in torsion/detorsion group than sham and healthy groups (p < .05). Compared with torsion/detorsion group, S. rebaudiana extract significantly reduced malondialdehyde level in treatment groups (p < .05). Torsion/detorsion group had significantly lower glutathione peroxidase and superoxide dismutase activities than sham and healthy groups, and these parameters showed significant increase in treatment groups compared with torsion/detorsion group (p < .05). The results revealed S. rebaudiana has this potential to protect the testes from ischaemia/reperfusion injury.

Topics: Animals; Drug Evaluation, Preclinical; Male; Malondialdehyde; Phytotherapy; Plant Extracts; Random Allocation; Rats, Wistar; Reperfusion Injury; Spermatic Cord Torsion; Stevia; Testicular Diseases

Occlusion of a cerebral artery impairs blood flow leading to neuronal death. Reperfusion of the tissue is associated with inflammation, increased reactive oxygen species, necrosis and apoptosis. Hence, damage to the brain will continue even after the blood flow is restored. Isosteviol has been demonstrated to have protective effects against ischemia-reperfusion (IR) injury in the rat heart and the current study was undertaken to determine whether it is also effective in preventing IR injury in the brain. Rats were divided into six groups: a sham-operation control group and 5 IR groups that were pre-treated with either isosteviol 5 mg.kg (-1), 10 mg.kg (-1), 20 mg.kg (-1), nimodipine 5 mg.kg (-1), or saline. Cerebral ischemia was induced for 2 hours. Twenty-two hours after re-perfusion the rats were assessed for neurobehavioral deficit, infarct volume, histological changes, and malondialdehyde, superoxide dismutase (SOD), Bcl-2 and NF-kappaB levels in brain tissue. Pre-treatment with isosteviol reduced infarct volume, ameliorated cell death and infiltration of neutrocytes, improved neuro-locomotor activity, increased SOD activity, induced Bcl-2, suppressed lipid superoxidation and the expression of NF-kappaB, and therefore retarded necrosis and apoptosis of neurons and inflammation. These positive effects were dose-dependent with an isosteviol dose of 20 mg.kg (-1), thus being as effective as nimodipine.

Topics: Animals; Diterpenes, Kaurane; Infarction, Middle Cerebral Artery; Male; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Stevia