Gut Dysbiosis, Sex, and Vascular Smooth Muscle Cells in Abdominal Aortic Aneurysms.

PURPOSE OF REVIEW: This paper reviews the present literature on how sex-related differences in gut dysbiosis influence vascular smooth muscle cell behavior in the pathogenesis of abdominal aortic aneurysms. RECENT FINDINGS: Emerging research has linked gut microbial metabolites, such as trimethylamine oxide and phenylacetyl glutamine, to abdominal aortic aneurysm pathogenesis via inflammation and vascular damage. Sex hormones also directly influence vascular smooth muscle cell phenotype switching, as estrogen has been found to be protective, while testosterone may enhance inflammation. Novel biomarkers and molecular regulators have emerged as potential targets, revealing new avenues for abdominal aortic aneurysm treatment. Gut dysbiosis contributes to abdominal aortic aneurysm progression through inflammation, vascular smooth muscle cell dysfunction, and immune activation. These effects vary by sex and are influenced by sex hormones and structural differences in vascular smooth muscle cells but require further investigation to establish a clear relationship.