Hypercholesterolemia and Lymphatic Defects: The Chicken or the Egg?

Area of Science:

• Cardiovascular Biology
• Lymphatic System Research
• Atherosclerosis Pathogenesis

Background:

• Lymphatic vessels are crucial for tissue fluid homeostasis, immune cell circulation, and lipid absorption.
• Hypercholesterolemia is increasingly recognized to impair lymphatic functions, contributing to atherosclerosis.
• Existing research indicates lymphatic system dysfunction exacerbates hypercholesterolemia and atherosclerotic lesion development.

Purpose of the Study:

• To review the contribution of abnormal lymphangiogenesis and lymphatic cholesterol transport to hypercholesterolemic atherosclerosis.
• To discuss the causal relationship between hypercholesterolemia and lymphatic system insults.
• To highlight current advancements in understanding these interconnected processes.

Main Methods:

• Literature review of studies investigating lymphatic vessel function in hypercholesterolemic models.
• Analysis of research on lymphangiogenic factors and their role in atherosclerosis.
• Examination of data from cholesterol-lowering interventions in animal models.

Main Results:

• Lymphatic vessel ablation or depletion of key growth factors (vascular endothelial growth factor-C and -D) in mice alters lipoprotein profiles, worsening hypercholesterolemia.
• Atherosclerotic lesions can attract periarterial lymphatics, leading to intimal invasion and altered immune cell trafficking.
• Cholesterol-lowering treatments have shown potential in preventing lymphatic drainage defects in hypercholesterolemic mice.

Conclusions:

• Aberrant lymphangiogenesis and impaired lymphatic cholesterol transport are significant contributors to hypercholesterolemic atherosclerosis.
• While a causal link is suggested, the precise mechanisms of hypercholesterolemia-induced lymphatic defects require further elucidation.
• Further research is needed to fully understand and target lymphatic system dysfunction in managing hypercholesterolemia and atherosclerosis.