Abstract:

Objective    To investigate the association of TRB3 gene +251A/G polymorphism with the alterations of left atrial function in the patietns with metabolic syndrome (MS) . Methods    A total of 177 MS patients and 156 gender- and age-matched healthy subjects as controls were included. Genomic DNA was obtained from peripheral blood leukocytes using standard phenol-chloroform extraction procedures. TRB3 gene +251A/G polymorphism was determined for all participants by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Strain rate imaging was preformed to assess left atrial function. Results    The distributions of genotypic and allelic frequencies of TRB3 gene +251A/G polymorphism showed significant differences between MS group and controls (all P<0.05).Compared with controls, the decreases in mean SSR and ESR, reflecting impairment of LA reservoir and conduit function in patients with MS, were significant (both P<0.001). However, mean ASR, an indicator of LA booster function, was similar in two groups (P>0.05). This finding suggested there were no changes in the booster function of left atrium. The carriers of G allele (AG and GG genotypes) demonstrated significantly lower mean SSR, mean ESR and mean ASR of left atrium than those in carriers of AA genotype in MS group (both P<0.05). Multiple linear regression analysis showed that G allele of TRB3 gene +251A/G polymorphism significantly correlated with mean ESR and mean ASR of LA (both P<0.05). Conclusion    TBB3 gene +251A/G polymorphism has been associated with alterations of LA function. The G allele of +251A/G polymorphism could be an important risk factor for deteriorations of LA function in the patients with metabolic syndrome.

Key words: Metabolic syndrome; TRB3 genetic polymorphisms; Left atrial function