Evaluation of Synergism and Carbon clearance model (Macrophage phagocytosis) by using Ethanolic extracts of Convolvulus pluricaulis, Michelia champaca and Chromolaena odorata in Rats

Background: Evaluation of preclinical immunomodulatory models are very crucial in drug discovery and development. Dysfunctional immune system is associated with disorders like autoimmune diseases, inflammatory diseases, cancer and as a treatment immunosuppressive or immunostimulant drugs are given aiming at immune system disease. Literature states that plants carry phytochemicals which exerts various biological activity in humans, mainly anti-inflammatory and anti-cancer properties which are likely to overcome the complications or adverse effects caused by synthetic drug treatments. Objective: To evaluate immunomodulatory effects of selected three medicinal plant extracts of Convolvulus pluricaulis (CP), Michelia champaca (MC), and Chromolaena odorata (CO) individually and to evaluate synergistic effects by combination index (CI) from herbal combination (COMB) prepared by combination of above three herbal extracts. Materials and Methods: The ethanolic extract of whole part of selected plants at low and high dose levels were subjected for macrophage phagocytosis by in-vivo Carbon clearance method based on acute oral toxicity studies. Results: The extracts showed increase in phagocytic index in comparison to control groups. Significant response was seen at both the dose levels for CP extract, at high dose for MC and CO extract and at low dose for COMB extract. Combination index: The combination index was found to be <1 for herbal combination, indicative of synergism among the drugs. Conclusion: The extracts has shown effects on cellular immune responses and has therapeutic potential to modulate the immune system and could be employed as an effective immunomodulatory plant in future. The combination of selected three herbal extracts was exerting synergistic effects to modulate immune system.