Researchers Uncover a Hidden Calcium–Cholesterol Connection

Scientists at the University of Alberta and McGill University have discovered a direct link between calcium and cholesterol, a discovery that could pave the way for new ways of treating high blood cholesterol. High blood cholesterol is a known risk factor for developing heart disease.

The researchers began the work after having their curiosity piqued while studying the role of a CALCIUM-BINDING PROTEIN. They noticed an extreme rise of blood cholesterol concentration in mice when the protein was not present.

The research paper is published in the journal Scientific Reports.

UAlberta researcher Marek Michalak and graduate student Wen-An Wang, along with McGill researcher Luis Agellon, teamed up with geneticist Joohong Ahnn from Hanyang University in Korea to discover that this physiological link between calcium and cholesterol is also preserved in worms.

"(This link) wasn't a trivial observation of a tissue cultured in a dish, but something that actually happens in animals. There is a mechanism inside the cell that senses when there is not enough cholesterol present and turns on the machinery to make more,” said Michalak, a distinguished university professor in the department of biochemistry.

“What we found is that a lack of calcium can hide cholesterol from this machinery. If you lose calcium, your synthetic machinery thinks there’s no cholesterol and it starts making more even if there is already enough,” added Michalak.

“Factors that affect blood cholesterol concentration have been studied for a long time,” said Agellon, a professor at McGill's School of Human Nutrition. “The general belief was that cholesterol controlled its own synthesis inside of cells, and then we discovered in our labs that calcium can control that function too. Finding this link potentially opens a door to developing new ways of controlling cholesterol metabolism.”

The researchers hope their finding leads to different approaches to patient care in the future, but say there is more work to be done. They are now looking to discover the common factor that allows calcium and cholesterol to communicate with each other in the cell and have received a four-year grant of $456,000 from the Canadian Institutes of Health Research to continue their work.