Reduced Levels of Selenium and Thioredoxin Reductase in the Thoracic Aorta Could Contribute to Aneurysm Formation in Patients with Marfan Syndrome

Marfan syndrome (MFS) is an autosomal dominant disorder caused by a heterozygous mutation of the FBN1 gene. MFS patients present oxidative stress that disturbs redox homeostasis. Redox homeostasis depends in part on the enzymatic antioxidant system, which includes thioredoxin reductase (TrxR) and glutathione peroxidases (GPx), both of which require an adequate concentration of selenium (Se). Therefore, the aim of this study was to determine if Se levels are decreased in the TAA of patients with MFS since this could contribute to the formation of an aneurysm in these patients. The results show that interleukins IL-1 & beta;, IL-6 TGF-& beta;1, and TNF-& alpha; (p & LE; 0.03), and carbonylation (p & LE; 0.03) were increased in the TAA of patients with MFS in comparison with control subjects, while Se, thiols (p = 0.02), TrxR, and GPx (p & LE; 0.001) were decreased. TLR4 and NOX1 (p & LE; 0.03), MMP9 and MMP2 (p = 0.04) and NOS2 (p < 0.001) were also increased. Therefore, Se concentrations are decreased in the TAA of MFS, which can contribute to a decrease in the activities of TrxR and GPx, and thiol groups. A decrease in the activities of these enzymes can lead to the loss of redox homeostasis, which can, in turn, lead to an increase in the pro-inflammatory interleukins associated with the overexpression of MMP9 and MMP2.

Automated summary

Marfan syndrome (MFS) is caused by a gene mutation, leading to oxidative stress that disturbs redox homeostasis. The study found decreased selenium levels in the thoracic aorta aneurysm (TAA) of MFS patients, along with increased inflammation and carbonylation. This decrease in selenium can contribute to the loss of redox homeostasis and overexpression of MMP9 and MMP2.