Can highly cited herbs in ancient Traditional Chinese medicine formulas and modern publications predict therapeutic targets for diabetes mellitus?

BACKGROUND

The prevalence of diabetes among all age groups worldwide was estimated to be more than 382 million in 2013. Traditional Chinese medicine (TCM) has been practiced for thousands of years, and substantial valuable experience and prescriptions have been accumulated in the TCM system for the treatment of diabetes. In recent decades, a large amount of experimental and clinical data has been published on the use of herbal medicines related to these ancient TCM prescriptions.

OBJECTIVE

This study aimed to discover a method for the investigation of potential antidiabetic herbs from the large amount of data in ancient TCM formulas and modern publications and to verify this method through an in vitro bioactivity study.

METHODS

In our review, the most frequently cited TCM herbs were selected as potential antidiabetic herb candidates on the basis of TCM philosophical theory (ancient TCM formulas) and Western medicine philosophical theory (modern publications). The ethanol and aqueous extracts of the selected herbs were screened for their α-glucosidase inhibitory, glucose-stimulated insulin secretion (GSIS), and intestinal glucose transport inhibitory effects.

RESULTS

Twelve herbs [Terminalia chebula Retz., fructus immaturus, dried; Poria cocos (Schw) Wolf., sclerotium, dried; Zea mays L., stigma, dried; Pueraria lobata (Willd.) Ohwi, radix, dried; Cucurbita moschata (Duch. ex Lam.) Duch. ex Poiret, fructus, dried; Lycium barbarum L., fructus, dried; Glycine max (L.) Merr., semen, fermented; Glycyrrhiza uralensis Fisch., radix and rhizoma, dried; Dioscorea opposita Thunb., rhizoma, dried; Morus alba L., folium, dried, Morus alba L., fructus, dried; and Polygonatum odoratum (Mill.) Druce, rhizoma, dried] were finally selected as candidates with potential glucose-lowering effects after a review was performed of herbs that are frequently cited in ancient TCM formulas and modern publications. The bioactive study results demonstrated that both the ethanol extracts and crude polysaccharides of M. alba L., fructus, dried, and M. alba L., folium, dried, and the crude polysaccharides of T. chebula Retz., fructus immaturus, dried, exhibited α-glucosidase inhibitory effects. Moreover, the crude polysaccharides of P. cocos (Schw) Wolf., sclerotium, dried; Z. mays L., stigma, dried; and T. chebula Retz., fructus immaturus, dried, exhibited favorable GSIS effects, and the ethanol extracts of P. odoratum (Mill.) Druce, rhizoma, dried; T. chebula Retz., fructus immaturus, dried; and G. uralensis Fisch., radix and rhizoma, dried, significantly decreased glucose transport across the cell monolayer.

CONCLUSIONS

Our review and the preliminary bioactive study revealed that 10 of the 12 recommended edible TCM herbs had favorable antidiabetic effects, demonstrating that TCM herbs with a high prescription and publication frequency may provide insights into the potential therapeutic targets of diabetes mellitus and may aid in the discovery of effective compounds complementary to currently used medicines. Such a literature and medicine review is a useful method of exploring potential antidiabetic herbs by using the wealth of information in ancient TCM formulas and modern publications.