Ethnopharmacology and Integrative Medicine: An Indian Perspective

Biodiversity of natural resources has served not only for the primary human needs but also for health care, since time immemorial. The Indian subcontinent, with the history of one of the oldest civilization, harbors many traditional health care systems. Their development was supported by the diverse biodiversity in flora and fauna due to variations in geographical landscaping. Ayurveda, whose history goes back to 5000 b.c., is one of the ancient health care systems. The Ayurveda was developed through daily life experiences with the mutual relationship between mankind and nature. The ancient text of Ayurveda reports more than 2000 plant species for their therapeutic potentials. Besides Ayurveda, other traditional and folklore systems of health care were developed in the different time periods in Indian subcontinent, where more than 7500 plant species were used. According to a WHO estimate, about 80% of the world population relies on traditional systems of medicines for primary health care, where plants form the dominant component over other natural resources. Renewed interest of developing as well as developed countries in the natural resources has opened new horizons for the exploration of natural sources with the perspectives of safety and efficacy. The development of these traditional systems of medicines with the perspectives of safety, efficacy and quality will help not only to preserve this traditional heritage but also to rationalize the use of natural products in the health care. Until recent past, the nature was considered as a compendium for templates of new chemical entities (NCEs). The plant species mentioned in the ancient texts of these Ayurveda and other Indian systems of medicines may be explored with the modern scientific approaches for better leads in the health care.

This commentary is based on a general concern regarding the low level of self-criticism (-evaluation) in the interpretation of molecular pharmacological data published in ethnopharmacology-related journals. Reports on potentially new lead structures or pharmacological effects of medicinal plant extracts are mushrooming. At the same time, nonsense in bioassays is an increasing phenomenon in herbal medicine research. Only because a dataset is reproducible does not imply that it is meaningful. Currently, there are thousands of claims of pharmacological effects of medicinal plants and natural products. It is argued that claims to knowledge in ethnopharmacology, as in the exact sciences, should be rationally criticized if they have empirical content as it is the case with biochemical and pharmacological analyses. Here the major problem is the misemployment of the concentration-effect paradigm and the overinterpretation of data obtained in vitro. Given the almost exponential increase of scientific papers published it may be the moment to adapt to a falsificationist methodology.

'Triphala' is one of the age-old, most commonly used polyherbal preparation from Ayurveda as Rasayana drug. This study was aimed at evaluating the effect of 'Triphala' on drug modulating enzymes to assess its safety through its potential to interact with co-administered drugs. The cytochrome P450 inhibitory effect of 'triphala' formulation was investigated on rat liver microsomes using CYP450-CO complex assay and on individual isoform such as CYP3A4 and 2D6 using fluorescence screening. RP-HPLC method was developed to standardize 'triphala' and its individual components using gallic acid as analytical marker compound. RP-HPLC analysis demonstrated the presence of gallic acid (4.30±2.09 mg/g) in the formulation. The formulation showed 23% inhibition of the rat liver microsomes through CYP450-CO complex assay which is comparatively less when compared with the individual components. Further, the effect of standardized formulation dissolved in ethanol showed CYP3A4 and CYP2D6 inhibitory activity at the IC(50) values of 119.65±1.91 μg/ml and 105.03±0.98 μg/ml respectively. Gallic acid was also found to inhibit both the isoforms at the IC(50) values of 87.24±1.11 μg/ml and 92.03±0.38 μg/ml respectively. Various concentrations of the formulation and its individual components showed significantly less inhibitory activity (p<0.001) on individual isoforms when compared with the positive control. Assessment on the in vitro effect of 'triphala' on drug modulating enzymes has important implications for predicting the likelihood of herb-drug interactions if these are administered concomitantly. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.