Protective effects of Croton hookeri on streptozotocin-induced diabetic nephropathy.

In this study, the protective effects of Croton hookeri (CH) extract on renal injury were investigated in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by a single injection of STZ (45 mg/kg) to Sprague-Dawley rats. After 5 days, CH extract (200 mg/kg) was administered daily by oral gavage for 2 weeks. Administration of CH extracts significantly reduced blood glucose levels in STZ-induced diabetic rats. STZ-induced changes in total cholesterol, LDL, HDL, ALT, AST, BUN, and serum creatinine levels were significantly restored by treatment with CH extract. Abnormal levels of SOD, catalase, glutathione, and oxidized GSH (GSSG) in STZ-treated rats were also significantly recovered by CH extract treatment. CH extract markedly reduced the expression of collagen-1, fibronectin, and α-SMA in the kidney of STZ-induced diabetic rats. In particular, oxidative DNA damages, MDA, TGF-ß, IL-1ß, and IL-6 levels were significantly reduced in STZ-treated rats following treatment with CH extract, whereas IL-10 showed opposite trend. STZ-induced SIRT1, SIRT3 downregulation and cloudin-1 upregulation in the kidney were dramatically recovered by CH extract treatment. Our data suggest that CH extract protects against diabetic-induced nephropathy by inhibiting oxidative stress and inflammation. Therefore, it has potential as a food supplement to alleviate renal dysfunction caused by diabetes-induced nephropathy.

The Gastroprotective Role of Acanthus ilicifolius - A Study to Unravel the Underlying Mechanism of Anti-Ulcer Activity.

Acanthus ilicifolius (Acanthaceae), a mangrove medicinal plant, is widely used by the local inhabitants of the Sundarbans (India) to treat a variety of diseases. As a part of our continued search for novel bioactive products from mangrove medicinal plants, we were able to document the anti-inflammatory effects of this plant. In the present study, we have performed a detailed evaluation of the gastroprotective activity of the methanolic extract of Acanthus ilicifolius using different models of gastric ulceration. Unlike the conventional non-steroidal anti-inflammatory drugs, a methanolic extract of Acanthus ilicifolius leaves (MEAL) possessing significant anti-inflammatory properties, as revealed from our previous studies displayed in rats in dosages of 200 mg and 400 mg/kg BW after intraperitoneal administration, showed significant protective activity (anti-ulcer activity) against the gastric lesions induced by aspirin, indomethacin, stress, ethanol, and pylorus ligation. In pylorus-ligated rats, administration of Methanolic extract of Acanthus ilicifolius leaves (MEAL) significantly decreased gastric volume, acidity, and peptic activity. Moreover, pre-treatment with MEAL significantly restored the levels of reduced glutathione (GSH) and the antioxidant enzyme superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX), along with significant inhibition of both lipid peroxidation and myeloperoxidase (MPO) activity in pylorus-ligated animals. Ulceration induced with ethanol was significantly inhibited with MEAL, and the extract also resulted in the reduction of both lipid peroxidation and myeloperoxidase activity. Furthermore, in this experimental model, administration of MEAL improved the activities of SOD, CAT, GSH, and GPX. A similar pattern of action was also noticed in cold-restraint stress-induced (CRS) ulceration, where MEAL pre-treatment inhibited CRS-induced ulceration, improved the status of antioxidant enzymes, and also reduced the level of lipid peroxides. These results suggest that extracts of the leaves of Acanthus ilicifolius may exhibit anti-ulcer activities additional to the anti-inflammatory properties.