Inhibition of Pro-inflammatory Enzymes and Growth of an Induced Rheumatoid Arthritis Synovial Fibroblast by Bruguiera cylindrica

Abstract

Background and Objective: Bruguiera cylindrica is a mangrove tree species. It has various medicinal uses including usage for, lower blood pressure, bleeding, hemorrhage and ulcers. This study aimed to investigate the anti-inflammatory and anti-rheumatoid arthritis effects of the plant. Materials and Methods: Extracts obtained from the leaves and roots of the plant were evaluated for their inhibitory effects against the enzymes: Cyclooxygenase-2, 5-Lipoxygenase and Acetylcholinesterase using the in vitro bioassay models. The GC-MS was used to determine the major active constituents. Synovial fibroblast cells were induced using TNF-alpha and IL-1 beta and MTT cell viability assay was used to determine the cell viability of both, the normal and the induced cells. Results: The DCM leave extract showed the highest inhibitory effects against the 3 enzymes tested. Fraction 6 (the main constituent was 1,2-Benzenedicarboxylic acid), possessed the strong activity against the 3 enzymes with inhibition percentage of 96% (IC50 = 56), 91% (IC50 = 44) and 89% (IC50 = 25) against 5-lipox, AChE and COX-2 enzymes, respectively. Fractions 1 and 3 (containing pyrrolidine related compound) showed inhibitory effects against the three enzymes with inhibition percentages ranging between 89 and 75%. The tested materials showed no cytotoxic effects at the highest concentration used (50 mu g mL(-1)) against the normal synovial cells but they possessed activities against the induced RA cell. The results indicated that the activities were dose-dependent. Conclusion: The metabolites obtained from B. cylindrica in this study possessed inhibitory effects on pro-inflammatory enzymes and cell viability of the induced RA cell line. These results provide scientific validation of the bio-efficacy of B. cylindrica as a source of potential bioactive substances for the treatment of inflammatory and arthritis-related diseases. Further study is needed to assess the observed bio-efficacy on an in vivo experiment.