Concentrated Grape Powder Consumption Modulates Cholesterol Metabolism and Homeostasis in Healthy Subjects.

Area of Science:

• Nutritional biochemistry
• Molecular biology
• Metabolic health

Background:

• Grape powder (GP) consumption has been shown to reduce circulating cholesterol levels in healthy individuals.
• The precise mechanisms underlying this cholesterol-lowering effect require further investigation.

Purpose of the Study:

• To elucidate the mechanisms by which concentrated grape powder (GP) reduces cholesterol.
• To evaluate biomarkers of cholesterol biosynthesis, intestinal absorption, miRNA regulation, and cholesterol oxidation.

Main Methods:

• Analysis of fasting plasma samples from 19 healthy subjects before and after 4 weeks of GP consumption.
• Gas chromatography-mass spectrometry (GC-MS) to measure cholesterol precursors and oxidation products.
• Real-time PCR to quantify plasma exosomal microRNA (miRNA).

Main Results:

• GP consumption significantly decreased lathosterol, a cholesterol synthesis precursor, indicating reduced cholesterol de novo biosynthesis.
• Cholesterol absorption markers (campesterol, β-sitosterol) remained unchanged.
• Plasma exosomal miRNA-1 levels increased, and a cholesterol oxidation product (27-hydroxycholesterol) was reduced.

Conclusions:

• GP consumption reduces cholesterol by inhibiting its synthesis and oxidation.
• Increased miRNA-1 may play a role in regulating cholesterol metabolism.
• Findings provide insights into the health benefits of grape consumption for cholesterol management.