A form of fat around many people's hearts yields chemicals that narrow the arteries and damage the organ, a Creighton University scientist speculates.
The fat in question appears to be produced by a high-fat, high-fructose diet, says Devendra Agrawal, a Creighton professor of biomedical sciences and other disciplines. Agrawal has received a $3.52 million federal grant to explore his hypothesis and examine whether vitamin D deficiency may contribute to the problem.
While scientists generally understand that fatty substances carried through the bloodstream narrow arteries, Agrawal hypothesizes that another cause of the problem is the secretion of chemicals by heavy, fatty tissue on top of the coronary arteries. The scientist hopes not only to make definitive findings about how a fatty diet may injure the heart, but also about the importance of vitamin D to heart health, particularly after stenting or angioplasty has been used to reopen an artery.
Agrawal will test his concept over the next five years in pigs, which have similar hearts to those of human beings. He expects his findings to be applicable to human beings and wants to produce research with value to heart-disease patients and those at risk of heart disease.
The pigs will receive high quantities of lard and high-cholesterol, high-fructose powders. Some will receive varying levels of vitamin D while others will remain deficient in vitamin D.
Agrawal, 59, has nine National Institutes of Health grants totaling more than $15 million, the most of any Creighton scientist. He has conducted research in asthma, plaque in the carotid artery, the use of grafts in heart bypasses and other topics. Agrawal, who has doctorates in medical sciences and biochemistry, has been at Creighton since 1985.
“He's a virtual idea factory,” Dr. William Hunter, a pathology professor and collaborator on this study, said of Agrawal. “I've known him for over 20 years and worked with him. He's constantly looking for new ways of looking at problems.”
Hunter will examine and evaluate tissue and cells for the study, among other tasks.
Agrawal said the fat around the heart typically gives energy to heart cells and provides a cushion around the organ. But fat deposited on the heart from a high-fat diet behaves differently and even looks different from other fatty tissue.
The scientist said one of his goals is to find which chemical or chemicals in this process are responsible for the narrowing of the arteries.