The Attenuation of Scutellariae radix Extract on Oxidative Stress for Colon Injury in Lipopolysaccharide-induced RAW264.7 Cell and 2,4,6-trinitrobenzene Sulfonic Acid-induced Ulcerative Colitis Rats.

Abstract

Background:Oxidative stress (OS) has been regarded as one of the major pathogeneses of ulcerative colitis (UC) through damaging colon. It has been shown that Scutellariae radix (SR) extract has a beneficial effect for the prevention and treatment of UC.Objective:The aim of this study was to investigate whether SR had a potential capacity on oxidant damage for colon injury both in vivo and in vitro.Materials and Methods:The 2,4,6-trinitrobenzene sulfonic acid (TNBS) was used to induce UC rats model while 1 μg/ml lipopolysaccharide (LPS) was for RAW264.7 cell damage. Disease activity index (DAI) was determined to response the severity of colitis. The myeloperoxidase (MPO) activity in rat colon was also estimated. The 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid assay was performed to evaluate the total antioxidant capacity of SR. Furthermore, the activity of glutathione peroxidase (GSH-PX), catalase (CAT), superoxide dismutase (SOD), and lipid peroxidation malondialdehyde (MDA) in cell supernatant and rat serum were detected by appropriate kits. In addition, an immunohistochemical assay was applied to examine transforming growth factor beta 1 (TGF-β1) protein expression in colon tissue.Results:The treatment with SR could significantly increase the activity of GSH-PX, CAT, and SOD associated with OS in LPS-induced RAW264.7 cell damage and TNBS-induced UC rats. However, the level of MDA was markedly reduced both in vitro and in vivo. Furthermore, SR significantly decreased DAI and reversed the increased MPO activity. Thus, SR could decrease the severity of acute TNBS-induced colitis in rats. Immunohistochemical assay showed that SR significantly downregulated TGF-β1 protein expression in colon tissue.Conclusion:Our data provided evidence to support this fact that SR attenuated OS in LPS-induced RAW264.7 cell and also in TNBS-induced UC rats. Thus, SR may be an interesting candidate drug for the management of UC.SUMMARY Scutellariae radix (SR) could significantly increase the activity of glutathione peroxidase, catalase, and superoxide dismutase associated with OS in lipopolysaccharide-induced RAW264.7 cell damage and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced ulcerative colitis ratsThe level of malondialdehyde was markedly reduced by SR both in vitro and in vivo SR could decrease the severity of acute TNBS-induced colitis in ratsSR could significantly downregulate the expression of transforming growth factor beta 1 protein in colon tissue. Abbreviations used: OS: Oxidative stress, UC: Ulcerative colitis, SR: Scutellariae radix, TNBS: 2,4,6-trinitrobenzene sulfonic acid, DAI: Disease activity index, MPO: Myeloperoxidase, GSH-PX: Glutathione peroxidase, CAT: Catalase, SOD: Superoxide dismutase, MDA: Malondialdehyde, TGF-β1: Transforming growth factor beta 1, OD: Optical density, ROS: Reactive oxygen species.