Published online Oct 7, 2015. doi: 10.3748/wjg.v21.i37.10662
Peer-review started: February 26, 2015
First decision: April 13, 2015
Revised: April 18, 2015
Accepted: July 8, 2015
Article in press: July 8, 2015
Published online: October 7, 2015
Processing time: 216 Days and 17.7 Hours
AIM: To investigate the plasma levels of betatrophin in patients with cirrhosis.
METHODS: Forty patients diagnosed at the clinic with liver cirrhosis according to biological, ultrasonographic, or histological criteria were included. The severity of cirrhosis was classified according to Pugh’s modification of Child’s classification and MELD score. Insulin resistance (IR) was assessed by the Homeostasis Model Assessment. A total of 20 patients showed a MELD score higher than 14. The control group consisted in 15 sex-and aged-matched subjects. Fasting blood samples were obtained for subsequent analysis. Serum insulin was determined by Liaison automated immune chemiluminiscence assay (DiaSorin S.p.A.) using a sandwich assay. The sensitivity of the assay was 0.2 μU/mL. The intra and interassay variation coefficients were < 4% and < 10%, respectively. The normal values were between 2 and 17 μU/mL. Human active betatrophin was analyzed by specific quantitative sandwich ELISA (Aviscera Bioscience®). The sensitivity of the assay was 0.4 ng/mL, and the intra and interassay reproducibility were < 6% and < 10%, respectively.
RESULTS: Plasma betatrophin levels were significantly increased in patients with cirrhosis compared with those in healthy subjects (P = 0.0001). Betatrophin levels were also associated with disease severity, being higher in Child-Pugh C patients compared to Child-Pugh B (P < 0.0005) and in patients who displayed a MELD score higher than 14 points compared to patients with lower punctuation (P = 0.01). In addition, we found a positive correlation between plasma betatrophin levels and the severity of cirrhosis according to Child-Pugh classification (r = 0.53; P < 0.01) or MELD score (r = 0.45; P < 0.01). In the overall cohort, a moderate correlation between serum betatrophin and plasmatic bilirrubin (r = 0.39; P < 0.01) has been observed, as well as an inverse correlation between betatrophin and albumin (r = -0.41; P < 0.01) or prothrombin time (r = -0.44; P <0.01). Moreover, insulin resistance was observed in 82.5% of the cirrhotic patients. In this group of patients, betatrophin levels were significantly higher than those in the group of patients without IR (P < 0.05).
CONCLUSION: Plasma betatrophin is increased in patients with cirrhosis. This increase is related to the severity of cirrhosis, as well as with the emergence of insulin resistance.
Core tip: Recently, Douglas A. Melton’s group from Harvard University reported the identification of betatrophin, a circulating protein secreted from the liver under insulin resistant states. Insulin resistance is common in patients with cirrhosis. In our study we confirm that betatrophin is increased in patients with liver cirrhosis, and the increase in plasma betatrophin levels is related to the severity of cirrhosis, and the emergence of insulin resistance. These preliminary results show that betatrophin may contribute to counteract, at least in part, insulin resistance in patients with cirrhosis.