Traditionally used Thai medicinal plants: In vitro anti-inflammatory, anticancer and antioxidant activities

J Ethnopharmacol 130(2):12 (2010) PMID 20435130

Aims of the study: In order to assess traditional Thai claims about the therapeutic potential of medicinal plants and to select plants for future phytochemical research, nine plant species with anti-inflammatory uses were selected from Thai textbooks and assessed for their in vitro anti-inflammatory, antiproliferative and antioxidant activities. Methods: Nuclear factor-kappaB (NF-@kB) inhibitory effects in stably transfected HeLa cells were determined by luciferase assay, and effects on LPS-induced pro-inflammatory mediators prostaglandin E2 (PGE2), interleukin (IL)-6, IL-1@b, and tumour necrosis factor (TNF)@a in primary monocytes were assessed by ELISA. Cytotoxic activities were examined against HeLa cells, human leukaemia CCRF-CEM cells and the multidrug-resistant CEM/ADR5000 subline using the MTT and XTT tests. However, a redox status has been linked with both inflammation and cancer, antioxidant effects were also assessed using the DPPH, lipid-peroxidation, and Folin-Ciocalteau methods. Results: Among all the nine species, Gynura pseudochina var. hispida and Oroxylum indicum showed the most promising NF-@kB inhibitory effects with the lowest IC"5"0 values (41.96 and 47.45@mg/ml, respectively). Muehlenbeckia platyclada did not inhibit the NF-@kB activation but effectively inhibited the release of IL-6, IL-1@b and TNF-@a with IC"5"0 values ranging between 0.28 and 8.67@mg/ml. Pouzolzia indica was the most cytotoxic against CCRF-CEM cells and the multidrug-resistant CEM/ADR5000 cells (9.75% and 10.48% viability, at 10@mg/ml, respectively). Rhinacanthus nasutus was the most potent cytotoxicity against HeLa cells (IC"5"0 3.63@mg/ml) and showed specific cytotoxicity against the multidrug-resistant CEM/ADR5000 cells (18.72% viability at 10@mg/ml, p0 0.08@mg/ml). Conclusions: This study provides in vitro evidence for the use of the Thai plants, most importantly Gynura pseudochina var. hispida, Oroxylum indicum and Muehlenbeckia platyclada as Thai anti-inflammatory remedies and these plants are now a priority for further phytochemical research.