Berberine and Its Potential Use to Combat Atherosclerosis

Berberine is an isoquinoline alkaloid extracted from various plants, including Berberis vulgaris, Berberis aquifolium, and Coptis chinensis. It has been widely used in traditional medicine in Asia for thousands of years to treat various ailments, including digestive disorders, diabetes, and infections. In recent years, it has gained attention for its potential in treating atherosclerosis, a chronic inflammatory disease that is the leading cause of cardiovascular disease (CVD) worldwide.

Atherosclerosis is a complex disease that is characterized by the accumulation of lipids and immune cells in the inner layer of arterial walls, leading to the formation of plaques. These plaques can rupture and cause thrombosis, leading to myocardial infarction or stroke. The underlying mechanisms of atherosclerosis are not fully understood, but recent evidence has shown that gut microbiota plays a crucial role in the development and progression of this disease.

Gut microbiota is a complex ecosystem of microorganisms that reside in the human gastrointestinal tract. They play a crucial role in nutrient metabolism, immune regulation, and host defense against pathogens. However, dysbiosis, an imbalance in the composition and function of gut microbiota, has been implicated in various diseases, including atherosclerosis.

One of the mechanisms by which gut microbiota contributes to atherosclerosis is through the choline-TMA-TMAO pathway. Choline is a nutrient that is abundant in animal products, such as meat, eggs, and dairy. When choline is metabolized by gut microbiota, it produces trimethylamine (TMA), which is then oxidized by liver enzymes to form trimethylamine N-oxide (TMAO). TMAO has been shown to promote atherosclerosis by enhancing foam cell formation, platelet activation, and endothelial dysfunction.

Berberine has been shown to down-regulate the choline-TMA-TMAO pathway in gut microbiota, thus reducing the risk of atherosclerosis. In a study published in Nature Communications, Zhang et al. (2019) investigated the effects of berberine on gut microbiota and atherosclerosis in ApoE-/- mice fed a high-fat diet. The results showed that berberine treatment significantly reduced the abundance of TMA-producing bacteria, such as Firmicutes and Proteobacteria, and increased the abundance of TMAO-degrading bacteria, such as Akkermansia and Bacteroides. This led to a significant reduction in plasma TMAO levels and atherosclerotic lesion size in the aortic arch and thoracic aorta.