Ph.D. Candidate The Chinese University of Hong Kong Hong Kong SAR, Hong Kong
Disclosure(s):
Yuhong Lin, MSc: No relevant financial relationship(s) with ineligible companies to disclose.
Objectives: Rising levels of cholesterol in the blood can lead to hypercholesterolemia, a condition associated with cardiovascular diseases. Several studies suggested that gut microbiota played a critical role in regulating plasma cholesterol. Houttuynia cordata Thunb. (HCT) is a well-known fishy vegetable that exhibits various pharmaceutical properties. In this study, the objectives were: 1) to investigate the effects of HCT extract (HCE) on plasma lipids in golden Syrian hamsters fed with a high-cholesterol diet and 2) to study the effects of HCE on gut microbiota remodeling.
Methods: Male hamsters were randomized into six groups: (1) NCD: hamsters were fed a normal cholesterol diet. (2) HCD: hamsters were fed a high-cholesterol diet. (3) L-HCAE: HCD hamsters were fed a low-dose HCT aqueous extract diet. (4) H-HCAE: HCD hamsters were fed a high-dose HCT aqueous extract diet. (5) L-HCEE: HCD hamsters were fed a low-dose HCT ethanolic extract diet. (6) H-HCEE: HCD hamsters were fed a high-dose HCT ethanolic extract diet, respectively. The hamsters were held for eight weeks. At the beginning and endpoint of the study, plasma lipid profiles were investigated. Hamster aortas were collected for fatty streak area analysis, and their feces were collected for gut microbiota study.
Results: Compared with the HCD, the HCEE-supplemented diet reduced plasma total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) of hamsters and prevented the formation of HCD-induced atherosclerotic plaque in a dose-dependent manner. HCEE performed better than HCAE in decreasing the plaque area in the aortas. The metagenomic analysis demonstrated that both HCAE and HCEE diets decreased the relative abundance of Firmicutes, but increased Bacteroidetes at the phylum level, reducing the F/B ratio. HCE promoted the growth of short-chain fatty acids (SCFAs)-producing bacteria by altering gut microbiota composition, ultimately reducing plasma lipid levels.
Conclusions: The results could provide a new perspective on the cholesterol-lowering effect of HCE and enhance our understanding regarding the application of HCE as a dietary functional food to maintain cholesterol homeostasis and the modulation of gut microbiota.
Funding Sources: State Key Laboratory of Agrobiotechnology (The Chinese University of Hong Kong)
