Correlation between polymorphisms in the visfatin gene and its expression in the serum and coronary artery calcification

Investigating Visfatin gene Polymorphism rs4730153 with Insulin Resistance and Non-Alcoholic Fatty Liver Diseases in Iranian Population

BACKGROUND

Visfatin is known as one of the adipokines associated with the development of inflammation, but its role in the pathogenesis of nonalcoholic fatty liver is less known so far. We aimed to investigate the association between visfatin gene polymorphism rs4730153 and insulin resistance and non-alcoholic fatty liver disease (NAFLD).

METHODS

This case-control study was performed on 80 patients with NAFLD as well as 80 healthy participants as controls referred to Amir Al-Momenin and Bouali hospitals in Tehran. Genotyping was performed using PCR-RFLP method. Plasma concentrations of visfatin and insulin were measured using ELISA kit. The fasting blood glucose, TC, TG, LDL-C, HDL-C, ALT, AST, SBP, DBP, and BMI levels were measured using the standard methods. Statistical analysis was also performed using SPSS software.

RESULTS

A significant difference was found in Visfatin level in the patients with NAFLD compared to this level in healthy individuals. The levels of HDL-C and LDL-C in healthy individuals and triglyceride in patients for GG, AG, and AA genotypes carriers also were significantly different. There was a significant relationship between rs4730153 polymorphism and insulin resistance; however, no association was found between this polymorphism and NAFLD. Notably, Visfatin showed a significant association with age (all individuals), body mass index (healthy individuals), insulin, and HOMA (in patients).

CONCLUSION

Visfatin levels reduced in patients with NAFLD. Moreover, rs4730153 polymorphism was indicated to be associated with both lipid metabolism and insulin resistance, but no association was found between this polymorphism and nonalcoholic fatty liver disease.

Accelerated cardiovascular risk after viral clearance in hepatitis C patients with the NAMPT-rs61330082 TT genotype: An 8-year prospective cohort study

Involvement of extracellular nicotinamide phosphoribosyltransferase (eNAMPT, i.e., visfatin or pre-B-cell colony-enhancing factor), a cancer metabokine, in chronically hepatitis C virus (HCV)-infected (CHC) patients with sustained virological responses (SVRs) remains elusive. This 8-year prospective cohort study evaluated eNAMPT profiles of 842 consecutive CHC patients, including 519 who had completed an anti-HCV therapy course and pre-therapy and 24-week post-therapy surveys. For 842 patients, pre-therapy associations were HCV RNA, homeostatic model assessment for insulin resistance (HOMA-IR) index, and body mass index with eNAMPT levels, and NAMPT-rs61330082 T allele with total cholesterol levels. NAMPT-rs10953502, NAMPT-rs2058539, and NAMPT-rs61330082 were in a linkage disequilibrium block, which was associated with total cholesterol levels. Compared to pre-therapy levels, at 24 weeks post-therapy, decreased eNAMPT and increased lipid levels were observed in SVR patients (n = 427). Among SVR patients, higher cumulative incidences of cardiovascular events occurred in those with a NAMPT-rs61330082 TT genotype than those with non-TT genotypes (28.2% vs. 8.4%, p < 0.001). NAMPT-rs61330082 TT genotype was independently associated with incident cardiovascular events (95% CI hazard ratio (HR): 1.88-10.37; HR: 4.415); no eNAMPT profiles were associated with incident malignancies. Of CHC patients, hepatic vascular endothelial cells and baseline peripheral leukocytes expressed higher eNAMPT levels than controls, and peripheral eNAMPT-positive leukocyte proportions decreased after SVR. During HCV infection, eNAMPT involvement in glucose metabolism was modulated by HCV RNA linked to lipid metabolism and NAMPT-associated SNPs. Hepatic endothelial cells and peripheral leukocytes potentially secrete eNAMPT. Caution is required for incident cardiovascular events in SVR patients with NAMPT-rs61330082 TT genotype.

Association of genetic variants in RETN, NAMPT and ADIPOQ gene with glycemic, metabolic traits and diabetes risk in a Chinese population

Abnormal serum levels of adipokine have been established to be a strong predictor of developing several human diseases including type 2 diabetes mellitus (T2DM). Association studies have reported several genetic variants in genes coding adipokines with contributions to T2DM susceptibility as well as some glycemic and metabolic traits, of which the single nucleotide polymorphisms (SNPs) of RETN, NAMPT, and ADIPOQ gene were well documented. However, little is known about contributions of these SNPs to above phenotypes in Chinese. In the current study, with availably quantitative glycemic and metabolic data from a total of 185 T2DM patients and 191 healthy controls, we tested associations between four SNPs of RETN, NAMPT, ADIPOQ gene and 13 glycemic and metabolic traits. The results showed that the rs1862513 and rs34861192 of RETN gene were functional and negatively correlated with the levels of serum creatinine and cholesterol, respectively. The rs16861194 of ADIPOQ gene was positively correlated with the aspartate aminotransferase (AST) and AST/alanine aminotransferase level. Moreover, the rs34861192 and rs13237989 of NAMPT gene synergistically affected the levels of insulin and glycemic index. However, due to the limited sample size, only the rs16861194 exerted a significant increased risk on T2DM. These results underscore the contributions of SNPs in RETN, NAMPT, ADIPOQ gene to glycemic and metabolic traits as well as T2DM susceptibility in Chinese.

Elevated serum visfatin levels are associated with poor prognosis of hepatocellular carcinoma

Visfatin is considered a pro-inflammatory adipocytokine, and it is commonly increased in obesity-related diseases. This study aimed to evaluate the levels of serum visfatin in patients with hepatocellular carcinoma (HCC) and its diagnostic and predictive value in detecting HCC. Fasting serum levels of visfatin of 135 HCC patients, 115 chronic hepatitis B (CHB) patients, 129 liver cirrhosis (LC) patients, and 149 healthy controls were determined via enzyme-linked immunosorbent assay. Meanwhile, serum alpha fetal protein (AFP) and interleukin-6 (IL-6) were also assayed. The median serum visfatin concentration in HCC patients was 1.113 ng/mL (range: 0.823-2.214 ng/mL), which was significant higher than those of healthy controls, CHB patients, and LC patients (P<0.05). The serum visfatin concentration in HCC patients was positively correlated with AFP (r=0.595, P<0.001) and IL-6 (r=0.261, P<0.015) and was also associated with tumor size and tumor node metastasis stage. Moreover, elevated levels of serum visfatin were associated with a higher HCC risk for CHB and LC patients. Multivariate Cox regression analysis had shown that HCC patients with high levels of serum visfatin had significantly shorter overall survival times than those with low serum visfatin levels (P<0.001). Using a cutoff visfatin level of 1.403 ng/mL, the receiver operating characteristic curve analysis showed unappealing sensitivity and specificity values (45.76% and 74.79%, respectively; AUC=0.626) regarding visfatin's use as a diagnostic marker for HCC. Our results indicate that increased serum visfatin levels are associated with poor prognosis of HCC. Visfatin may be a potential therapeutic target of HCC.