Using Chinese natural products for diabetes mellitus drug discovery and development

This paper provides a review of natural Chinese drug products, including phytochemic compounds, medicinal herbs and multi-component herbal formulae, that have been reported to possess hypoglycemic activity with mechanisms for antidiabetic action. Along with a great number of combination formulae, ∼ 187 different Chinese medicinal herbs are clinically applied to treat diabetes mellitus and its complications in China, most of which have achieved reasonably good clinical outcomes. These valuable data and practical experience provide a promising opportunity for the discovery and development of drug candidates with good therapeutic efficacy and low toxicity. The concept of treating complex, multifactorial metabolic diseases, such as diabetes, using multi-component therapeutics, including single-herb formulae and combination herbal formulae, shall be regarded as a concerted pharmacologic intervention of multiple compounds interacting with multiple targets and possessing interdependent activities that are required for a synergistic or optimal effect. The conventional approach for the discovery and development of antidiabetic drug products from natural products involving a high-throughput, bioactivity guided drug screening of single compounds obtained from thousands of herbs has proven to be a costly and non-productive effort. Hence, an alternative way of developing new drug candidates, as suggested in this review, is to reduce and simplify a well-established combination herbal formula, along with the pharmacologic evaluation of a small group of phytochemic compounds, which are therapeutically effective as the original formula and have known chemical structures, compositions and mechanisms of action that are similar to chemical drugs.