Dracocephalum moldavica L. tea alleviates high-fat diet-induced hyperlipidemia in rats via gut microbiota and lipid metabolism

Abstract

Hyperlipidemia is a common metabolic disorder and a major risk factor for cardiovascular diseases. Dracocephalum moldavica L., a species of Dracocephalum in the family Labiatae, has a long history of medicinal use, often as tea (non-Camellia tea) to lower blood sugar and lipid levels. However, its exact mechanism of action remains unknown, hindering its therapeutic effectiveness. In this study, the lipid-regulating mechanism of the ethyl acetate extract of D. moldavica (EAD) was evaluated. The chemical constituents of EAD were preliminarily characterized using ultra-high performance liquid chromatography. A rat model of hyperlipidemia was induced by a high-fat diet and different doses of EAD were administered. Body weight, liver weight, and kidney weight were measured, along with biochemical indexes related to lipid metabolism. Intestinal content samples were analyzed using 16S rRNA sequencing technology to determine differences in intestinal bacterial composition. Differential metabolites were identified by serum metabolomics. The results showed that EAD reduced the weight of rats on a high-fat diet, along with liver weight and kidney weights, approaching levels similar to those in the normal group. Biochemical indexes related to lipid metabolism in the serum of rats on a high-fat diet were also improved. Furthermore, daily supplementation of EAD induced structural changes in the gut microbiota of rats, particularly by regulating the relative abundance of important microbes. Additionally, enrichment of metabolite metabolic pathways in plasma revealed the regulation of amino acid metabolism and primary bile acid synthesis after EAD administration. These results indicate that EAD alleviates hyperlipidemia in rats by regulating lipid metabolism and gut microbiota, providing insight into dyslipidemia regulation by D. moldavica.