Houston Methodist scientists reversed infertility in sterile mice by reducing high-circulating cholesterol with a bacterial protein, showing further evidence that links high cholesterol to female infertility. This is a promising development, with one in every five women of childbearing age in the U.S. unable to get pregnant after trying for a year.
Serum opacity factor sets off a biochemical cascade that ultimately results in getting rid of excess cholesterol. ApoE proteins on lipid-rich HDL bind to their receptors in the liver initiating cholesterol's breakdown. High-density lipoprotein (HDL); Apolipoprotein E (ApoE); Apolipoprotein AI (ApoAI). Credit: Houston Methodist "We are working with a protein, called serum opacity factor, with unique characteristics," said Corina Rosales, Ph.D., assistant research professor of molecular biology in medicine with the Houston Methodist Research Institute and lead author on the study. "In our experiments, serum opacity factor lowered cholesterol levels by over 40% in three hours. So, this protein is quite potent." The results are published in the Journal of Lipid Research. While this protein's primary function is to increase bacterial colonization, it also alters the structure of cholesterol-carrying high-density lipoproteins, or HDLs, making it easier for the liver to dispose of the excess cholesterol that's preventing conception. The researchers also noted that serum opacity factor's dramatic action on HDL could be leveraged as a potential alternative to statins, which are the current gold standard for lowering cholesterol in people with atherosclerosis. HDL, known as the "good cholesterol," carries excess cholesterol from different tissues to the liver for breakdown, thereby bringing down cholesterol levels. However, if there is HDL dysfunction, lipid metabolism gets altered,…