A mouse study led by a team of biomedical scientists from the University of California, Riverside (UCR), found that phthalate, a chemical used to make plastics more durable, led to increased plasma cholesterol levels.
Plastics, part of modern life, are useful but can pose a significant challenge to the environment and may also constitute a health concern. Indeed, exposure to plastic-associated chemicals, such as base chemical bisphenol A and phthalate plasticizers, can increase the risk of human cardiovascular disease. What underlying mechanisms cause this, however, remain elusive.
A team led by Mr. Changcheng Zhou, a professor in the UCR School of Medicine founded DCHP, a widely used phthalate plasticizer that has recently been proposed by the Environmental Protection Agency (EPA) as a high-priority substance for risk evaluation. Not much is known yet about DCHP’s adverse effects on humans.
“We found dicyclohexyl phthalate, or DCHP, strongly binds to a receptor called pregnane X receptor, or PXR. DCHP ‘turns on’ PXR in the gut, inducing the expression of key proteins required for cholesterol absorption and transport. Our experiments show that DCHP elicits high cholesterol by targeting intestinal PXR signaling.”
The researchers also found that mice exposed to DCHP had more circulating “ceramides” in their intestines, a type of waxy lipid molecules linked to an elevated risk of cardiovascular disease in humans, in a way that was PXR-dependent.
“Our results provide insights and new understandings of the impact of plastic-associated chemicals on high cholesterol, or dyslipidemia and cardiovascular disease risk,” added Mr. Zhou.