Role of a gitogenin-type steroidal saponin (3-O-beta-D-glucopyranosyl (1 -> 2)-beta-D-glucopyranosyl (1 -> 4)-beta-D-galactopyranoside-25R, 5 alpha-spirostane-2 alpha,3 beta-diol), isolated from the leaves of Malvastrum coromandelianum in regulating thyrotoxicosis in rats

摘要

The hitherto unknown role of saponin in the regulation of thyrotoxicosis has been revealed in chemically-induced thyrotoxic rats. L-T-4 (L-thyroxine) administration at pre-standardized dose of 500-mu g/kg body weight for 12 days increased the levels of thyroid hormones, enhanced the activity of hepatic 5'-monodeiodinase I (5'DI) and glucose-6-phosphatase (G-6Pase) as well as lipid peroxidation (LPO) with a parallel decrease in the levels of antioxidative enzymes. However, administration of the isolated saponin for 15 days ameliorated the T-4-induced alterations in serum thyroid hormones, hepatic LPO, G-6-Pase and 5'DI activity, and improved the cellular antioxidant status, indicating its antithyroidal and antioxidative potential. These effects of the test compound were comparable to a reference antithyroid drug, Propylthiouracil (PTU), suggesting that the test saponin may act as a potent anti-thyroid agent. (C) 2016 Elsevier Ltd. All rights reserved.