Study Links Vitamin D Deficiency to Abdominal Aortic Aneurysm Progression Through Immune Pathway
A preprint study found that vitamin D3 deficiency accelerates abdominal aortic aneurysm (AAA) development in mice by activating a complement immune pathway called C3a. The research used genetic analysis of human tissue, animal models, and cell studies to trace the mechanism. The findings suggest vitamin D supplementation or blocking C3a signaling could potentially slow AAA progression and reduce rupture risk.
Researchers investigating the role of vitamin D in abdominal aortic aneurysm development found that deficiency of this nutrient exacerbates the disease through activation of the complement C3a immune pathway. Using single-cell RNA sequencing on human aortic tissue, they identified differences in vitamin D and complement-related genes in diseased versus healthy tissue. In mouse models, vitamin D3-deficient diets led to increased aortic dilation, immune cell infiltration, inflammatory markers, and elastic fiber breakdown, while blocking C3a receptors with a pharmacological antagonist significantly reduced aneurysm formation. Laboratory studies on vascular smooth muscle cells showed that active vitamin D (calcitriol) suppressed C3a production. The authors propose that restoring vitamin D sufficiency or targeting C3a signaling could represent new therapeutic approaches for limiting AAA growth.
What's missing
The study's limitations include reliance on murine models, which may not fully translate to human disease; the sample size and characteristics of human tissue samples are not specified; long-term effects of C3a receptor antagonism are not addressed; and the optimal vitamin D levels for AAA prevention in humans remain undefined. The authors do not discuss potential confounding factors in human vitamin D deficiency or whether findings apply to AAAs of different etiologies.
What different sources said
- bioRxivCenter
Vitamin D3 Deficiency Exacerbates Abdominal Aortic Aneurysm Progression Via Complement C3a Activation
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