To establish a new quality assessment method based on the regulation of intestinal microbiota in type 2 diabetes by lignans of Schisandra chinensis (Turcz.) Baill

Abstract

Ethnopharmacological relevance

The mature fruit of Schisandra chinensis, a traditional Chinese medicinal herb, is primarily utilized for the management of diabetes. Its principal bioactive constituents include lignans, polysaccharides, and organic acids. Nonetheless, a standardized quality control methodology grounded in the therapeutic efficacy of Schisandra chinensis (Turcz.) Baill. for diabetes treatment has yet to be developed.

Aim of the study

Due to the diverse origins, intricate composition, and multiple therapeutic targets of Schisandra chinensis Fructus, relying on a single index component for quality control is challenging. Consequently, this study proposes a novel quality evaluation approach, integrating pharmacological activity and intestinal microbiota analysis, to assess the efficacy of Schisandra chinensis Fructus in diabetes management.

Materials and methods

Twelve batches of Schisandra chinensis Fructus from diverse origins were selected for lignan content analysis, and 3 representative batches were subsequently chosen for pharmacological experiments pertaining to diabetes. The relationship between lignan content in Schisandra chinensis Fructus and its pharmacological efficacy was assessed by evaluating the recovery rates of eleven serum biochemical markers affected by Schisandra lignans. Furthermore, 16S rRNA gene sequencing was utilized to explore the association between the gut microbiota in diabetic rats and the lignan content in Schisandra chinensis Fructus.

Results

The results of serum biochemistry analyses demonstrate that Schisandra lignans significantly decrease bone gamma-carboxyglutamate protein (BGP), blood lipid levels, and oxidative stress in diabetic rats, thereby conferring hepatoprotective effects. Correlation analysis between the constituents and pharmacological effects revealed a positive relationship between the anti-diabetic efficacy of Schisandra chinensis Fructus and its total lignan content. Furthermore, Schisandra lignans were observed to enhance gut microbiota diversity in diabetic rats, mitigate the dysbiosis induced by Type 2 Diabetes Mellitus (T2DM), and increase the abundance of beneficial bacterial species.

Conclusions

The observed variations in the efficacy of Schisandra chinensis Fructus from different sources may be attributed to differences in total lignan content. The higher the total lignan content in Schisandra chinensis Fructus, the stronger its protective effect. Based on the analysis of component-efficacy-microbiota correlation this study has identified a chisandrin content of ≥3.5 mg/g and a total lignan content of≥17 mg/g as quality evaluation indicators for the improvement of T2DM by Schisandra chinensis Fructus.