An unprecedented study demonstrates that potassium-packed foods such as bananas and avocados may help to prevent hardening of the arteries, or pathogenic vascular calcification. Researchers at the University of Alabama at Birmingham have shown that a diet lacking in potassium promotes elevated arterial stiffness, while a diet with increased potassium levels can actually lessen arterial stiffness.
Vascular calcification is linked to an increased risk of fatal heart disease and other cardiovascular events. The research team set out to examine the underlying mechanisms of this vascular condition in apolipoprotein E-deficient mice, which are prone to cardiovascular disease. The mice were fed either high, low, or normal levels of dietary potassium.
The team discovered that the mice fed a low-potassium diet had a significant increase in vascular calcification. On the other hand, the mice fed a high-potassium diet had significantly restrained vascular calcification. By using an arterial stiffness indicator called pulse wave velocity, the researchers also found that the low-potassium mice had increased stiffness of their aortas and high-potassium mice had decreased aortic stiffness.
“The findings have important translational potential since they demonstrate the benefit of adequate potassium supplementation on prevention of vascular calcification in atherosclerosis-prone mice, and the adverse effect of low potassium intake,” explained co-author Paul Sanders.
The researchers also took a look into the vascular effects of potassium intake on a molecular level. Low potassium amounts in a cell culture noticeably strengthened calcification of vascular smooth muscle cells. Previous research has shown that calcification of vascular smooth muscle cells resembles the differentiation of bone cells, which leads to the conversion of smooth muscle cells into bone-like cells.
With this in mind, the researchers set out to examine the growth of vascular smooth muscle cells in low-potassium cell culture. They found that the low-potassium conditions triggered the expression of several gene markers that are characteristic of bone cells while inhibiting the expression of vascular smooth muscle cell markers. This indicates that low-potassium conditions promote the transformation of the vascular smooth muscle cells into bone-like cells.
The findings of this study, which will appear in the journal JCI This Month in November, emphasize the importance of potassium in the diet. The research also provides a foundation for the development of new therapies to prevent or treat atherosclerotic vascular calcification.