Serum level of soluble CD26/dieptidyl peptidase-4 (DPP-4) activity correlates with other liver disease biomarkers both in Asian and European patients

Serum IP-10 levels and increased DPPIV activity are linked to circulating CXCR3+ T cells in cholestatic HCV patients

BACKGROUND & AIMS

Serum interferon-gamma-inducible protein-10 (IP-10) is elevated in cholestatic liver diseases and predicts response to antiviral therapy in patients with chronic hepatitis C virus (HCV) infection. Dipeptidylpeptidase 4 (DPPIV) cleaves active IP-10 into an inactive form, which inhibits recruitment of CXCR3+ T cells to the liver. In this study the link between IP-10 levels, DPPIV activity in serum and CXCR3+ T cells is analysed in cholestatic and non-cholestatic liver patients.

METHODS

In serum DPPIV activity (by enzymatic assay), IP-10 (by ELISA) and bile acids (BA) (by enzymatic assay) were analysed in 229 naive HCV genotype (GT) 1 patients and in 16 patients with cholestatic liver disease. In a prospective follow-up (FU) cohort of 27 HCV GT 1 patients peripheral CD3+CXCR3+, CD4+CXCR3+ and CD8+CXCR3+ cells were measured by FACS.

RESULTS

In 229 HCV patients serum IP-10 levels correlated positively to DPPIV serum activity. Higher IP-10 levels and DPPIV activity were detected in cholestatic and in cirrhotic HCV patients. Increased IP-10 serum levels were associated with therapeutic non-response to antiviral treatment with pegylated-interferon and ribavirin. In the HCV FU cohort elevated IP-10 serum levels and increased BA were associated with higher frequencies of peripheral CD3+CXCR3+, CD4+CXCR3+ and CD8+CXCR3+ T cells. Positive correlation between serum IP-10 levels and DPPIV activity was likewise validated in patients with cholestatic liver diseases.

CONCLUSIONS

A strong correlation between elevated serum levels of IP-10 and DPPIV activity was seen in different cholestatic patient groups. Furthermore, in cholestatic HCV patients a functional link to increased numbers of peripheral CXCR3+ immune cells could be observed. The source of DPPIV release in cholestatic patients remains open.

Increased prevalence and risk of non-alcoholic fatty liver disease in overweight and obese patients with Type 2 diabetes in South China

AIMS

To investigate the prevalence of and risk factors for non-alcoholic fatty liver disease in overweight and obese patients with Type 2 diabetes mellitus.

METHODS

We recruited patients with Type 2 diabetes with a BMI ≥ 24 kg/m² , who visited the diabetes clinics of 60 hospitals in 21 cities in Guangdong Province, China from August 2011 to March 2012. Anthropometric measurements, biochemical tests and abdominal ultrasonography were performed for all the patients.

RESULTS

The study included 3861 patients (1860 men) with a mean ± sd (range) age of 58.91 ± 13.06 (18-90) years. Non-alcoholic fatty liver disease was found in 1751 patients (45.4%), with a significantly higher prevalence among men than women (48.0 vs 42.9%). The peak of non-alcoholic fatty liver disease prevalence was in patients with a BMI of 34-35 kg/m² , those with a triglyceride/HDL cholesterol ratio of 5.5-6.0, men aged < 30 years and women aged 40-50 years. Assessment using the BARD (BMI, aspartate aminotransferase/alanine aminotransferase ratio, diabetes) score system showed that the prevalence of advanced fibrosis was 80.52% in all patients and that women had a higher prevalence than men (86.52 vs 74.16%). Multiple logistic regression analyses showed that dyslipidaemia, BMI and 2-h postprandial plasma glucose were independent risk factors for non-alcoholic fatty liver disease, while heart rate and female gender were protective factors.

CONCLUSION

The prevalence of non-alcoholic fatty liver disease in overweight and obese patients with Type 2 diabetes in South China is high. Multiple metabolic disorders were significantly associated with non-alcoholic fatty liver disease in overweight and obese patients with Type 2 diabetes.

Cord serum dipeptidyl-peptidase 4 activity in gestational diabetes

BACKGROUND

Tissue-specific dipeptidyl-peptidase 4 (DPP4) dysregulation has been described in adults with diabetes mellitus. The DPP4 -incretin system has not been studied in foetal life. In this study, DPP4 activity and glucagon-like peptide-1 (GLP-1) levels were assessed in cord blood of neonates born to women with gestational diabetes mellitus (GDM) and nondiabetic controls.

MATERIAL AND METHODS

This study has been conducted in two Hungarian and one Austrian centres.

PATIENTS

A total of 568 pregnant women were enrolled in the study after their OGTT between the 24th and 28th gestational week. Cord blood samplings with DPP4 activity and GLP-1 level measurements were possible in 270 (DPP4: 159 control, 111 GDM) and 112 (GLP-1: 72 control, 40 GDM) cases. OGTT (24-28th gestational week) and cord blood sampling at delivery were performed. Cord serum DPP4 activity was determined in a continuous monitoring microplate-based kinetic assay, and cord plasma GLP-1 was measured using a fluorescence ELISA method.

RESULTS

Cord serum DPP4 activity was lower in GDM [mean (95% CI): 28.07 U/L (26.32-29.82 U/L)] than in controls [31.61 U/L (29.93-33.29 U/L), MWU P = 0.0015]. Cord plasma active GLP-1 levels were close to the lower detection limit and were not altered in GDM (control: mean = 3.43 pM, 95% CI: 3.04-3.82 pM, GDM: mean = 3.61 pM, 95% CI: 2.96-4.28 pM - MWU test P = 0.6).

CONCLUSIONS

Decreased cord serum DPP4 activity in gestational diabetes mellitus might be the result of an adaptive foetal response or an early dysregulation in the entero-insular axis with consequences beyond the incretin system. Cord plasma GLP-1 levels may reflect the missing oral intake with a limited glucose sensing of L cells via the circulation in foetal life.

Non-alcoholic fatty liver disease and type 2 diabetes mellitus: The liver disease of our age?

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease that might affect up to one-third of the adult population in industrialised countries. NAFLD incorporates histologically and clinically different non-alcoholic entities; fatty liver (NAFL, steatosis hepatis) and steatohepatitis (NASH-characterised by hepatocyte ballooning and lobular inflammation ± fibrosis) might progress to cirrhosis and rarely to hepatocellular cancer. NAFL increasingly affects children (paediatric prevalence is 4.2%-9.6%). Type 2 diabetes mellitus (T2DM), insulin resistance (IR), obesity, metabolic syndrome and NAFLD are particularly closely related. Increased hepatic lipid storage is an early abnormality in insulin resistant women with a history of gestational diabetes mellitus. The accumulation of triacylglycerols in hepatocytes is predominantly derived from the plasma nonesterified fatty acid pool supplied largely by the adipose tissue. A few NAFLD susceptibility gene variants are associated with progressive liver disease, IR, T2DM and a higher risk for hepatocellular carcinoma. Although not approved, pharmacological approaches might be considered in NASH patients.