Promotion of atherosclerosis by Helicobacter cinaedi infection that involves macrophage-driven proinflammatory...

Area of Science:

• Microbiology
• Cardiovascular Research
• Immunology

Background:

• Helicobacter cinaedi is a common cause of human bacteremia.
• Its role in atherosclerosis remains largely unknown.

Purpose of the Study:

• To investigate the association between H. cinaedi infection and atherosclerosis.
• To explore the mechanisms underlying this potential link in vitro and in vivo.

Main Methods:

• Utilized hyperlipidemic mouse models to study atherosclerosis progression.
• Employed in vitro cell culture models (macrophages, THP-1 monocytes) to examine cellular responses.
• Analyzed aortic root lesions for inflammatory cell infiltration and gene expression.
• Detected bacterial RNA (cytolethal distending toxin) in infected aortas.

Main Results:

• H. cinaedi infection significantly exacerbated atherosclerosis in mice.
• Increased neutrophil and foam cell accumulation was observed in aortic lesions.
• Bacteria-mediated upregulation of pro-inflammatory genes contributed to lesion development.
• H. cinaedi altered cholesterol metabolism in macrophages, leading to foam cell formation.
• Bacterial infection induced differentiation of THP-1 monocytes.

Conclusions:

• Provides the first experimental evidence of H. cinaedi's pathogenic role in atherosclerosis.
• Suggests a potential contribution of enterohepatic Helicobacter species to cardiovascular disease.
• Highlights the need for further research into the link between H. cinaedi and atherosclerosis.