[Non-alcoholic fatty liver disease and non-alcoholic steatohepatitis]

Genetic variants in COL13A1, ADIPOQ and SAMM50, in addition to the PNPLA3 gene, confer susceptibility to elevated transaminase levels in an admixed Mexican population

Non-alcoholic fatty liver disease (NAFLD) is the accumulation of extra fat in liver cells not caused by alcohol. Elevated transaminase levels are common indicators of liver disease, including NAFLD. Previously, we demonstrated that PNPLA3 (rs738409), LYPLAL1 (rs12137855), PPP1R3B (rs4240624), and GCKR (rs780094) are associated with elevated transaminase levels in overweight/obese Mexican adults. We investigated the association between 288 SNPs identified in genome-wide association studies and risk of elevated transaminase levels in an admixed Mexican-Mestizo sample of 178 cases of NAFLD and 454 healthy controls. The rs2896019, rs12483959, and rs3810622 SNPs in PNPLA3 and rs1227756 in COL13A1 were associated with elevated alanine aminotransferase (ALT, ≥40IU/L). A polygenic risk score (PRS) based on six SNPs in the ADIPOQ, COL13A1, PNPLA3, and SAMM50 genes was also associated with elevated ALT. Individuals carrying 9-12 risk alleles had 65.8% and 48.5% higher ALT and aspartate aminotransferase (AST) levels, respectively, than those with 1-4 risk alleles. The PRS showed the greatest risk of elevated ALT levels, with a higher level of significance than the individual variants. Our findings suggest a significant association between variants in COL13A1, ADIPOQ, SAMM50, and PNPLA3, and risk of NAFLD/elevated transaminase levels in Mexican adults with an admixed ancestry. This is the first study to examine high-density single nucleotide screening for genetic variations in a Mexican-Mestizo population. The extent of the effect of these variations on the development and progression of NAFLD in Latino populations requires further analysis.

Nonalcoholic steatohepatitis-related hepatocellular carcinoma: is there a role for the androgen receptor pathway?

The epidemic of insulin resistance, obesity, and metabolic syndrome has led to the emergence of nonalcoholic steatohepatitis (NASH) as the most common cause of liver disease in the US. Patients with NASH are at an increased risk for hepatic disease-related morbidity and death, and chronic inflammation in NASH patients can lead to hepatocellular carcinoma (HCC). The prevalence of HCC is higher in males than in females, and genetic studies have identified androgen and androgen receptors (ARs) as partially responsible for the gender disparity in the development of liver disease and HCC. Although many factors are known to play important roles in the progression of inflammation in NASH patients, the role of androgen and AR in the progression of NASH to HCC has been understudied. This review summarizes the evidence for a potential role of androgen and the AR pathway in the development of NASH-related HCC and in the treatment of HCC. It has been proposed that AR plays a role in the progression of HCC: inhibitory roles in early stages of hepatocarcinogenesis and tumor-promoting roles in advanced stages. AR can be activated by several pathways, even in the absence of androgen. While AR has been explored as a potential therapeutic target in HCC, several clinical trials have failed to demonstrate a clinical benefit of antiandrogen drugs in HCC. This review discusses the potential reason for these observations and discuss the potential future trials design in this important setting.

Association between resistin +299A/A genotype and nonalcoholic fatty liver disease in Chinese patients with type 2 diabetes mellitus. Gene. 2013;529:340-344. [PMID: 23954219 DOI: 10.1016/j.gene.2013.08.001]

OBJECTIVE

To investigate the relationship between the resistin intronic +299G/A polymorphism and nonalcoholic fatty liver disease (NAFLD) in patients with type 2 diabetes mellitus (T2DM).

METHODS

We selected 738 T2DM patients, including 395 with NAFLD and 343 without fatty liver disease, as well as 279 healthy control individuals, and analyzed their resistin +299G/A polymorphism genotype by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

Plasma resistin levels in T2DM patients with NAFLD were at the highest (P<0.05). The frequency of AA genotype at the +299 site of the resistin gene in patients with concurrent T2DM combined with NAFLD was significantly different from that in the control (P<0.05). The AA genotype was found to be associated with a 1.80-fold increased risk for T2DM combined with NAFLD, 2.05-fold increased risk for obesity and 2.37-fold increased risk for obesity of abdominal type compared to the GG (P<0.05, respectively). The multivariate non-conditional logistic regression model analysis further shows that the AA genotype is a risk factor for the development of NAFLD in T2DM patients (OR, 2.32; 95% CI, 1.05-4.68; P<0.05).

CONCLUSION

The resistin +299AA genotype may be associated with increases in the risk of the NAFLD development in T2DM patients.

Non-alcoholic Fatty Liver Disease and Chronic Kidney Disease in Koreans Aged 50 Years or Older

Background

Non-alcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD) share common pathogenic mechanisms and many risk factors, and both are linked to an increased risk of cardiovascular diseases. The aim of this study was to assess the association between NAFLD and CKD according to the presence of hypertension and diabetes mellitus in Koreans aged 50 years or older.

Methods

A cross-sectional study of 1,706 subjects who received their routine health examination was conducted between May 2008 and April 2010 at Konkuk University medical center. Biochemical tests for liver and abdominal ultrasonography were performed. CKD was defined as either proteinuria or glomerular filtration rate ≤60 mL/min per 1.73 m².

Results

Among the 1,706 subjects, There were 545 (31.9%) with non-alcoholic fatty liver disease and 424 (24.9%) with chronic kidney disease. In univariate logistic regression analysis, NAFLD was significantly associated with CKD (odds ratio [OR], 1.69; 95% confidence interval [CI], 1.34 to 2.12). In multivariate logistic regression analysis adjusted for age, sex, current smoking, abdominal obesity, aspartate aminotransferases, alanine aminotransferases, γ-glutamyltransferase, hypertension, diabetes mellitus, hypertriglyceridemia, and low high-density lipoprotein cholesterol, NAFLD was associated with CKD (adjusted OR, 1.68; 95% CI, 1.27 to 2.24). This relationship remained significant after classification according to the presence of hypertension or diabetes mellitus.

Conclusion

NAFLD diagnosed by ultrasonography was significantly associated with CKD in Koreans aged 50 years or older.

[Elevated liver enzymes in rheumatoid arthritis : differential diagnostic considerations based on a case report]

Elevated liver enzymes in patients with rheumatoid arthritis may have various causes. These can range from the rheumatic disease itself, the anti-rheumatic medication or be the manifestation of an associated autoimmune disease. We present the case of a 19-year-old female with known seropositive rheumatoid arthritis who developed severe liver damage after 9 months of anti-rheumatic therapy with leflunomide and adalimumab. Both drugs were stopped. In addition to the underlying disease and the specific anti-rheumatic drugs, a temporary therapy with flucloxacillin as well as an association with newly diagnosed celiac disease had to be considered as possible causes of elevated liver enzymes. Following repeated liver biopsy, autoimmune hepatitis was assumed and prednisolone and azathioprine were initiated. Elevated liver enzymes and bilirubin rapidly returned to normal values.