Environmental pollution (Barking, Essex : 1987)Jul 3, 2019

The body’s internal clock protein helps increase artery-damaging enzymes in acrolein-linked artery disease, involving changes in gut bacteria

Circadian Biology Weekly Brief ↗PubMed ↗DOI ↗

Updated Mar 31, 2026

Abstract

Patients with atherosclerosis exhibited higher levels of MMP9 and lower expression of Clock and Bmal1.

MMP9 is identified as a promising biomarker for atherosclerosis.
Acrolein exposure increased MMP9 and decreased the expression of Clock and Bmal1 in human umbilical vein endothelial cells.
Knockdown of Clock or Bmal1 resulted in upregulation of MMP9 in endothelial cells.
Atherosclerotic mice exposed to acrolein showed similar changes in MMP9, Clock, and Bmal1 levels.
Acrolein exposure altered gut microbiota composition, specifically increasing Firmicutes and decreasing Bacteroidetes.
Gut microbiota changes correlated with levels of atherosclerotic plaque, MMP9, and Bmal1.

Simplified

Circadian rhythm is believed to play important roles in atherosclerosis. The gut microbiota is found to be closely related to atherogenesis, and shows compositional and functional circadian oscillation. However, it's still unclarified whether circadian clock and intestinal microbiota are involved in the progression of atherosclerosis induced by environmental pollutant acrolein. Herein, patients with atherosclerosis showed higher MMP9, a promising biomarker for atherosclerosis, and lower Bmal1 and Clock expression in the plasma. Interestingly, acrolein exposure contributed to the increased MMP9, decreased Clock and Bmal1, and activated MAPK pathways in human umbilical vein endothelial cells (HUVECs). We found that knockdown of Clock or Bmal1 lead to upregulation of MMP9 in HUVECs, and that Clock and Bmal1 expression was elevated while MAPK pathways were blocked. Atherosclerotic apolipoproteinE-deficient mice consumed a high-fat diet were used and treated with acrolein (3 mg/kg/day) in the drinking water for 12 weeks. Upregulation of MMP9, and downregulation of Clock and Bmal1 were also observed in plasma of the mice. Besides, acrolein feeding altered gut microbiota composition at a phylum level especially for an increased Firmicutes and a decreased Bacteroidetes. Additionally, gut microbiota showed correlation with atherosclerotic plaque, MMP9 and Bmal1 levels. Therefore, our findings indicated that acrolein increased the expression of MMP9 through MAPK regulating circadian clock, which was associated with gut microbiota regulation in atherosclerosis. Circadian rhythms and gut microbiota might be promising targets in the prevention of cardiovascular disease caused by environmental pollutants.

Full Text

Full text is available at the source.

View Full Text ↗

The body’s internal clock protein helps increase artery-damaging enzymes in acrolein-linked artery disease, involving changes in gut bacteria

Abstract

Full Text

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief

Abstract

Full Text

Related papers

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief