EFFECTS OF PORPHYRA VIETNAMENSIS EXTRACT ON TNBS-INDUCED COLITIS IN RATS

Objective: This study aimed to investigate the intestinal anti-inflammatory activity of a methanolic extract of Porphyra vietnamensis in the TNBS model of intestinal inflammation in rats. Methods: The study included (i) Identification and quantification of Porphyra-334 in P. vietnamensis, (ii) investigation of the effect of methanolic extract on DNA cleavage induced by H₂O₂ UV-photolysis, (iii) 500 µg/ml Porphyra methanolic extract (PE) loaded 20% pluronic F127 gel was prepared, and its gelation, gel melting temperatures as well as bio-adhesive strength were determined, (v) anti-inflammatory potential of PE against the intestinal inflammatory process induced by TNBS (trinitro-benzesulphonic acid) in rats was evaluated. The protective effects were evaluated as follows: evaluation of intestinal damage (damage score, colon weight) and adherence to adjacent organs, colon malondialdehyde (MDA) estimation. Results: 0.0317% w/w of P-334 with R_f value of 0.48 was calculated from the methanolic extract of Porphyra. PE showed a dose-dependent (300-500 µg/L) protective effect on DNA cleavage. In contrast with Mesalamine (a standard anti-inflammatory drug), treatment with purified P-334 and gel (500 µg/L) formulation containing PE showed significant protective effects in the TNBS-induced colon damage. PE treatment positively scored on histopathological parameters. The post-treatment intestinal features showed restoration at par with the healthy intestine. Conclusions: 1000 mg of PE per kg rat weight showed significant mucorestorative in TNBS-induced colonic damage rats. The observed anti-inflammatory and antioxidant effects may be associated with the presence of P-334 in P. vietnamensis.