Anti-inflammatory medicinal plants and the molecular mechanisms underlying their activities

Background: Medicinal plant and plant products have shown tremendous potentials and are used beneficially in the treatment of inflammation and in the management of diseases with significant inflammatory components. Many medicinal plants employed as anti-inflammatory and antiphlogistic remedies lack the gastro-erosive side effects of non-steroidal anti-inflammatory drugs (NSAID) or the plethora of unwanted side effects associated with steroidal anti-inflammatory drugs. In order to harness and optimise the applications of these herbs in inflammatory diseases, there is a need to understand how these herbs produce their anti-inflammatory actions.Materials and Methods: This paper is a review of some anti-inflammatory herbs and their molecular mechanisms of action. A literature search and analysis of published manuscript was employed to x-ray research findings that show how medicinal plants produce anti-inflammatory activities.Results: Many studies have shown that anti-inflammatory activities of herbal extracts and herb-derived compounds are mainly due to their inhibition of arachidonic acid (AA) metabolism, cyclo-oxygenase (COX), lipo-oxygenase (LOX), pro-inflammatory cytokines, inducible nitric oxide, and transcription activation factor (NF-êB). Some anti-inflammatory medicinal herbs are reported to stabilize lysosomal membrane and some cause the uncoupling of oxidative phosphorylation of intracellular signalling molecules. Many have also been shown to possess strong oxygen radical scavenging activities.Conclusion: Most of the mechanisms by which anti-inflammatory medicinal plants act are related and many herbal products have been shown to act through a combination of these molecular pathways.Key words: Medicinal plants, antiinflammatory, mechanism of action, molecular pathways.