Study links high cholesterol, cardiovascular disease to plastics

Date:
December 1, 2021
Source:
University of California - Riverside
Summary:
In a mouse study, a team led by a biomedical scientist found a
phthalate -- a chemical used to make plastics more durable --
led to increased plasma cholesterol levels.



FULL STORY ========================================================================== 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 Changcheng Zhou, a biomedical scientist at the University
of California, Riverside, now raises the hopes of solving the mystery. In
a mouse study, the researchers found a phthalate -- a chemical used to
make plastics more durable -- led to increased plasma cholesterol levels.

"We found dicyclohexyl phthalate, or DCHP, strongly binds to a receptor
called pregnane X receptor, or PXR," said Zhou, who is a professor in
the UCR School of Medicine. "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." DCHP, a widely used phthalate plasticizer, has recently been proposed by the Environmental Protection
Agency as a high-priority substance for risk evaluation. Not much is
known yet about DCHP's adverse effects in humans.

"To our knowledge, our study is the first to show the effects of DCHP
exposure on high cholesterol and cardiovascular disease risk in mouse
models," Zhou said. "Our results provide insights and new understandings
of the impact of plastic-associated chemicals on high cholesterol --
or dyslipidemia -- and cardiovascular disease risk." Zhou's team also
found that mice exposed to DCHP had in their intestines higher circulating "ceramides" -- a class of waxy lipid molecules associated with increased cardiovascular disease risk in humans -- in a way that was PXR- dependent.

"This, too, points to the potentially important role of PXR in
contributing to the harmful effects of plastic-associated chemicals on cardiovascular health in humans," Zhou said.

Zhou was joined in the research by Zhaojie Meng, Jinwei Liu, Rebecca
Hernandez, and Miko Gonzales of UCR; and Yipeng Sui, Taesik Gwag, and
Andrew J. Morris of the University of Kentucky. The study was published
in Environmental Health Perspectives, a top journal in the environmental
health field.

The work was supported in part by the National Institute of Environmental Health Sciences, or NIEHS. Hernandez was supported by a recently renewed
NIEHS training grant to UCR. Gonzales, an undergraduate student, was a
UCR honors Capstone scholar.

========================================================================== Story Source: Materials provided by
University_of_California_-_Riverside. Original written by Iqbal
Pittalwala. Note: Content may be edited for style and length.


========================================================================== Journal Reference:
1. Yipeng Sui, Zhaojie Meng, Jianzhong Chen, Jingwei Liu, Rebecca
Hernandez,
Miko B. Gonzales, Taesik Gwag, Andrew J. Morris, Changcheng
Zhou. Effects of Dicyclohexyl Phthalate Exposure on PXR Activation
and Lipid Homeostasis in Mice. Environmental Health Perspectives,
2021; 129 (12) DOI: 10.1289/EHP9262 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2021/12/211201085157.htm

--- up 2 weeks, 6 days, 2 hours, 55 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)