Loss of embryonically-derived Kupffer cells during hypercholesterolemia accelerates atherosclerosis development

Area of Science:

• Immunology
• Hepatology
• Cardiovascular Research

Background:

• Hypercholesterolemia is a primary risk factor for atherosclerosis.
• Liver Kupffer cells (KCs) are crucial for immune surveillance and cholesterol homeostasis.
• The impact of hypercholesterolemia on KC homeostasis is not well understood.

Purpose of the Study:

• To investigate how hypercholesterolemia affects Kupffer cell homeostasis.
• To determine the consequences of altered KC populations on liver cholesterol and atherosclerosis.

Main Methods:

• Induction of hypercholesterolemia in a mouse model.
• Analysis of Kupffer cell populations (embryo-derived vs. monocyte-derived).
• Assessment of cholesterol accumulation, oxidative stress, and atherosclerotic plaque development.

Main Results:

• Embryo-derived KCs (EmKCs) initially expand in hypercholesterolemia, accumulating cholesterol via CD36.
• EmKCs undergo mitochondrial oxidative stress, leading to their diminished numbers.
• Monocyte-derived KCs (MoKCs) repopulate the KC pool but have reduced cholesterol-loading capacity.
• Reduced EmKC proportion exacerbates liver cholesterol accumulation and atherosclerosis.

Conclusions:

• KC homeostasis is significantly perturbed during hypercholesterolemia.
• The shift from EmKCs to MoKCs impairs cholesterol regulation and promotes atherosclerosis.
• Targeting KC dynamics may offer therapeutic strategies for hypercholesterolemia and cardiovascular disease.