Functional variants of eNOS and iNOS genes have no relationship to the portal hypertension in patients with liver cirrhosis

Abstract

Objective. Nitric oxide is an important vasoactive mediator. Changes in NO production, caused by functional variants of both endothelial and inducible NO synthase (eNOS, iNOS), might play a role in portal hypertension. The aim was to study the significance of functional eNOS and iNOS gene variants in cirrhotic patients and their interrelationship to both inflammatory and endothelial activation parameters. Material and methods. One hundred and thirty-two patients with liver cirrhosis (age 36–72 years) and 101 controls were examined for functional variants of eNOS (E298D, 27bpintr4, 786T/C) and iNOS (R221W, S608L) genes. Inflammatory (IL6, IL8, IL10) and vasoactive (sVCAM-1, E-selectin) cytokines were measured using ELISA kits. Results. The frequency of E298D (GG 12%, GT 41%, TT 47%), 28bpintr4 (AA 6%, AB 28%, BB 66%), 786T/C genotypes (CC 17%, CT 45%, TT 38%), as well as R221W (CC 93%, CT 7%, TT 0%), and S608L (CC 65%, CT 32%, TT 3%) genotypes in cirrhotic patients did not differ from the controls (p > 0.05 for all comparisons). No relationship was found between the frequency of these genotypes and the severity of portal hypertension, or either inflammatory or vasoactive cytokines. A positive correlation was found between hepatic venous pressure gradient and cytokine concentration: sVCAM-1, IL6, IL8, IL10. Conclusions. Examined eNOS and iNOS variants have no relationship to pathogenesis of liver cirrhosis. Severity of portal hypertension was associated with the changes in endothelial activation.

Key Words::

• cirrhosis
• eNOS/iNOS functional variants
• hemodynamic parameters
• portal hypertension

Acknowledgments

Financial support: Supported by Grants NT 11247/4 and NT 12290/4 from the Czech Ministry of Health and Grant SVV UK-3362 from Charles University in Prague.

Declaration of interest: All authors state that there is no conflict of interest. The authors have no financial or personal relationship that might bias presented work.