Evaluation of Transforming Growth Factor-β Signaling Pathway in the Wall of Normal and Varicose Veins

Abstract

Objective(s): Extracellular matrix remodeling in the vein wall is involved in varicose vein pathogenesis, with transforming growth factor β₁ (TGF-β₁) playing a potential role. The aim of the study was to assess the TGF-β signaling pathway including its receptor (TGF-β RII) and phosphorylated receptor-regulated Smads (p-Smad2/3) in varicose veins. Methods: Varicose veins from patients undergoing varicose vein surgery were the studied material, whereas normal greater saphenous veins from patients undergoing infrainguinal arterial bypass surgery were the control material. Expression of TGF-β RII mRNA was assessed with RT-PCR, whereas expression of TGF-β RII and p-Smad2/3 proteins was assessed with Western blot. Results: A significantly increased TGF-β RII mRNA level was found in varicose veins (287 ± 24%), when compared with normal veins (100 ± 26%). The receptor protein expression reflected a changed mRNA level with significantly increased TGF-β RII protein in varicose veins (290 ± 21%), when compared with controls (100 ± 16%). Enhanced TGF-β RII expression was accompanied by increased p-Smad2/3 protein expression in varicose veins (257 ± 19%) in comparison with normal veins (100 ± 9%). Conclusion(s): Increased TGF-β RII expression and activation in the wall of varicose veins may be involved in extracellular matrix remodeling related to TGF-β₁ and supports its role in the disease pathogenesis.