Effect ofAgaricus blazeiMurill on the Pulmonary Tissue of Animals with Streptozotocin-Induced Diabetes

Abstract

The present study was designed to evaluate the oxidative stress as well as the therapeutic effect of Agaricus blazei Muril (A. Blazei) in rats with streptozotocin-induced diabetes. We used 25 Wistar rats, and DM was induced by injecting streptozotocin (70 mg/Kg i.p.). Agaricus blazei Muril was administered daily starting 40 days after disease onset. A. Blazei was tested as an aqueous extract for its phytochemical composition, and its antioxidant activity in vitro was also evaluated. Lipoperoxidation (LPO), and superoxide dismutase (SOD), catalase, and glutathione peroxidase activities were measured in the pulmonary tissue, as well as the presence of inducible nitric oxide synthase (iNOS), through immunohistochemistry. An anatomopathologic study was also performed. Phytochemical screening of A. Blazei detected the presence of alkaloids and saponins. The extract exhibited a significant antioxidant activity in the DPPH-scavenging and the hipoxanthine/xanthine oxidase assays. Pulmonary LPO increased in diabetic animals (0.43 ± 0.09; P < .001) as compared to the control group (0.18 ± 0.02), followed by a reduction in the A. Blazei-treated group (0.33 ± 0.04; P < .05). iNOS was found increased in the lung in diabetic rats and reduced in the A. Blazei-treated group. The pulmonary tissue in diabetic rats showed oxidative alterations related to the streptozotocin treatment. The A. Blazei treatment effectively reduced the oxidative stress and contributed to tissue recovery.

Treatment with Aqueous Extract fromCroton cajucaraBenth Reduces Hepatic Oxidative Stress in Streptozotocin-Diabetic Rats

“…Increased levels of TBARS, an end-product of lipoperoxidation, were found previously in the liver of streptozotocin-induced diabetic rats [39–41]. In this study, the TBARS increase confirms this finding, which indicates an overall oxidative stress increase in diabetic rats.…”

Potential Biochemical Mechanisms of Lung Injury in Diabetes

“…As NO and superoxide can react simultaneously to produce peroxynitrite that is very damaging [ 64 ], any evidence that NO concentration is elevated in the diabetic lung would suggest that NO/peroxynitrite pathway is a mechanism by which lung is injured. The pulmonary lipid peroxidation, glutathione peroxidase activities and inducible nitric oxide synthase (iNOS) were all found to be increased in streptozotocin diabetic rats [ 65 ]. Immunohistochemical staining in the pulmonary bronchial epithelium and capillary endothelium in the DM group indicates an elevated level of iNOS expression [ 65 ].…”

Untitled

“…Also, it has been shown that dietary supplementation with natural antioxidants such as vitamins C and E, melatonin and flavonoids attenuates the oxidative stress and diabetic state induced by STZ 24,25 . The present study evaluates the in-vivo antioxidant activity of S. pinnata extract in diabetic rats Increased concentration of malonaldehyde, an endproduct of lipid peroxidation, were found in the liver homogenates of streptozotocin-induced diabetic rats 26,27 . In this study, the increase confirms this finding, which indicates an overall increase in oxidative stress in diabetic rats.…”