African genetic ancestry is associated with lower frequency of PNPLA3 G allele in non-alcoholic fatty liver in an admixed population.

INTRODUCTION AND OBJECTIVES: PNPLA3 (rs738409) and TM6SF2 (rs58542926) variants, interindividual and ethnic differences may be risk factors for non-alcoholic fatty liver disease (NAFLD). The PNPLA3 G allele is associated with worse NAFLD evolution in Hispanics and Caucasians. TM6SF2 is associated with hypertriglyceridemia, NAFLD, and cardiovascular disease. We aimed to evaluate the association between genetic ancestry by Ancestry Informative Markers (AIM), PNPLA3 and TM6SF2 polymorphisms in patients with biopsy-proven NAFLD in an admixed population. METHODS: We included adults with biopsy-proven NAFLD and excluded patients with the presence of other chronic liver disease, alcohol intake >100g/week, HIV, drug-induced fatty liver disease, or liver transplantation. We classified NAFLD using the Non-Alcoholic Steatohepatitis Clinical Research Network (NASH-CRN) histological scoring system. The PNPLA3 (rs738409 c.444C>G) and TM6SF2 (rs58542926 c.449C>T) genotyping were performed by RT-PCR. Genetic ancestry was determined using 46 insertion-deletion AIM; α<0.05 was considered significant. RESULTS: A total of 248 patients with NAFLD were enrolled [34 with simple steatosis (NAFL); 214 with NASH]. Overall, we detected a greater European ancestry contribution (0.645), followed by African (0.173), Amerindian (0.095), and East Asian (0.087) ancestry contribution, without differences between NAFL and NASH patients. However, we found a higher African genetic ancestry contribution among patients with NAFL who had the PNPLA3 C/C genotype than those with the G allele (0.216 ± 0.205 versus 0.105 ± 0.101, respectively; p=0.047). Ancestry contributions did not differ among TM6SF2 genotypes. CONCLUSION: Among NAFL patients, greater African genetic ancestry was associated to a lower frequency of the PNPLA3 G allele, demonstrating a possible NASH ancestry-related protective factor.

Synbiotic Supplementation Modulates Gut Microbiota, Regulates ß-Catenin Expression and Prevents Weight Gain in ob/ob Mice: Preliminary Findings.

BACKGROUND: Obesity is one of the main health problems in the world today, and dysbiosis seems to be one of the factors involved. The aim of this study was to examine the impact of synbiotic supplementation on obesity and the microbiota in ob/ob mice. Twenty animals were divided into four groups: obese treated (OT), obese control (OC), lean treated (LT) and lean control (LC). All animals received a standard diet for 8 weeks. The treated groups received a synbiotic (Simbioflora-Invictus Farmanutrição Ltd., Sao Paulo, Brazil) in water, while the nontreated groups received only water. After 8 weeks, all animals were sacrificed, and gut tissue and stool samples were collected for mRNA isolation and microbiota analysis, respectively. ß-Catenin, occludin, cadherin and zonulin in the gut tissue were analyzed via RT-qPCR. Microbiome DNA was extracted from stool samples and sequenced using an Ion PGM Torrent platform. RESULTS: Synbiotic supplementation reduced body weight gain in the OT group compared with the OC group (p = 0.0398) and was associated with an increase in Enterobacteriaceae (p = 0.005) and a decrease in Cyanobacteria (p = 0.047), Clostridiaceae (p = 0.026), Turicibacterales (p = 0.005) and Coprococcus (p = 0.047). On the other hand, a significant reduction in Sutterella (p = 0.009) and Turicibacter (p = 0.005) bacteria was observed in the LT group compared to the LC group. Alpha and beta diversities were different among all treated groups. ß-Catenin gene expression was significantly decreased in the gut tissue of the OT group (p ≤ 0.0001) compared to the other groups. No changes were observed in occludin, cadherin or zonulin gene expression in the gut tissue. CONCLUSIONS: Synbiotic supplementation prevents excessive weight gain, modulates the gut microbiota, and reduces ß-catenin expression in ob/ob mice.

Usefulness of collagen type IV in the detection of significant liver fibrosis in nonalcoholic fatty liver disease.

INTRODUCTION/AIMS: Liver fibrosis assessment is a key issue in the evaluation of nonalcoholic fatty liver disease (NAFLD) patients. In the present study, we aimed to validate a noninvasive marker panel to assess significant and advanced fibrosis in these patients. METHOD: 126 biopsy-proven NAFLD patients were included. NAFLD diagnosis was based on histological criteria. Fibrosis stages were determined according to NASH-Clinical Research Network criteria. Clinical and laboratorial data were collected during the interval of three months before or after liver biopsy. Histological fibrosis stages were classified as significant fibrosis (F2-F4) and advanced fibrosis (F3-F4). Five serum biomarkers [hyaluronic acid (HA), collagen type IV (cIV), procollagen type III (PC III), laminin (LN) and cholylglycine (CG)] were assessed by chemiluminescence immunoassays. RESULTS: Most patients were female (61.61%), mean age: 55.7 ±â€¯9.13 years old and mean BMI was 32.1 ±â€¯5.9 kg/m2. Prevalence of diabetes, dyslipidemia, arterial hypertension, and metabolic syndrome was 68.75%, 82.29%, 63.54% and 81.05%, respectively. Patients with cIV above 30 ng/mL had a 5.57-times (IC: 1.86-16.69) the chance of having significant fibrosis and 7.61-times (IC: 2.27-25.54) the chance of having advanced fibrosis versus patients with values below 30 ng/mL. HA, PC III, LN and CG did not detect the presence of significant and advanced fibrosis. The AUROC of clV for detection of significant (0.718) and advanced fibrosis (0.791) was better than that of other serum biomarkers. CONCLUSION: Type 4 collagen could predict the presence of significant and advanced fibrosis in NAFLD patients and it would be a useful tool in routine clinical practice.

Diagnostic performance of three non-invasive fibrosis scores (Hepamet, FIB-4, NAFLD fibrosis score) in NAFLD patients from a mixed Latin American population.

INTRODUCTION AND AIMS: Several non-invasive scoring systems have been developed and validated worldwide to predict the risk of liver fibrosis in nonalcoholic fatty liver disease (NAFLD). However, information about the performance of these systems in Latin American populations is scarce. Our aim was to evaluate the performance of the Hepamet Fibrosis Score, Fibrosis-4 (FIB-4) and the NAFLD Fibrosis Score (NFS) in a mixed Latin American group of NAFLD patients. METHODS: Clinical, laboratory and liver biopsy data collected from 379 biopsy-proven NAFLD patients from Latin American tertiary health centers were reviewed. Histological fibrosis stages were classified using the Kleiner score. Accuracy was determined, and new fibrosis score thresholds were calculated to better compare the performances of non-invasive tests and to explore their usefulness in excluding fibrosis. RESULTS: The distribution of fibrosis stages among the sample population was as follows: F0 (45%), F1 (27%), F2 (8%), F3 (16%) and F4 (4%). Using modified thresholds, the areas under the ROC curves (AUROC) for Hepamet and FIB-4 (0.73 and 0.74, respectively) to detect significant fibrosis were higher than that of NFS (0.58). However, the AUROCs of the three scores were not significantly different in advanced fibrosis and cirrhosis. To exclude fibrosis, we calculated lower cutoffs than standard thresholds for Hepamet, FIB-4 and NFS with similar performances. CONCLUSION: Thresholds of non-invasive fibrosis scores (Hepamet, FIB-4 and NFS) can be modified to maximize diagnostic accuracy in Latin American patients with NAFLD.

Microbiota and nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH).

Genetic predisposition, the intestinal microbiota (IM) and environmental factors, such as sedentary lifestyle and inadequate diet, should be considered as critical factors for the development of nonalcoholic fatty liver disease (NAFLD). Recently, some studies have demonstrated an association between dysbiosis and NAFLD; however, the exact mechanisms that lead to intestinal membrane damage, bacterial translocation and inflammation are not well elucidated. Due to the relevance of this theme, the IM and its metabolites have received special attention in recent years in an attempt to better understand the mechanisms related to the prevention, physiopathology, and treatment of NAFLD. In this paper, we provide a review of the human IM and its role in diet, obesity, and the development/progression of NAFLD/NASH, as well as the use of prebiotics and probiotics in the modulation of IM.

Validation of PNPLA3 polymorphisms as risk factor for NAFLD and liver fibrosis in an admixed population.

INTRODUCTION AND AIM: Studies have shown that two polymorphisms were associated with steatosis and progression of non-alcoholic fatty liver disease (NAFLD) in different populations: the Patatin-like Phospholipase Domain Containing 3 (PNPLA3) and Transmembrane 6 Superfamily Member 2 (TM6SF2). However, the frequency and significance of these polymorphisms in an admixed population, i.e., Brazilian, is unknown. Therefore, we aimed to evaluate them in healthy subjects in comparison to patients with NAFLD. MATERIAL AND METHODS: This was a multicenter cross-sectional study in 248 patients with biopsy-proven NAFLD and in 134 healthy controls from two tertiary centers in Brazil. PNPLA3 (rs738409 c.444C>G) and TM6SF2 (rs58542926 c.449C>T) polymorphisms were evaluated. RESULTS: In controls, the frequencies of PNPLA3 CC and CG+GG were 49.25% and 50.74%, respectively; in NAFLD patients, this was 31.05% and 68.88% (p=0.0044, 95% CI 1.037-2.977). PNPLA3 GG subjects had an increased risk (3.29-fold) of having NAFLD when compared to CC subjects (p=0.0044, 95% CI 1.504-7.225). In patients with nonalcoholic steatohepatitis (NASH), PNPLA3 GG compared to CC was associated with higher AST levels [38.4±25.3 versus 36.7±40.1IU/L, p=0.0395)] and with the presence of liver fibrosis (≥F2 fibrosis, p=0.0272). TM6SF2 polymorphisms were not in Hardy-Weinberg equilibrium in our NAFLD group precluding further analysis. CONCLUSION: We demonstrated for the first time that PNPLA3 CG+GG increase the risk of NAFLD among Brazilian subjects. Moreover, PNPLA3 GG was associated with liver enzyme elevation and fibrosis in NASH patients.

Association between the CYBA and NOX4 genes of NADPH oxidase and its relationship with metabolic syndrome in non-alcoholic fatty liver disease in Brazilian population.

BACKGROUND: Oxidative stress has been implicated in the progression of severe forms of non-alcoholic fatty liver disease (NAFLD). NADPH oxidase produces reactive oxygen species. In the present study, we investigated for the first time two single nucleotide polymorphisms (SNPs) in the regulatory region of genes encoding NADPH oxidase 4 (NOX4) and p22phox (CYBA) in NAFLD. METHODS: A total of 207 biopsy-proven NAFLD patients [simple steatosis (n = 27); nonalcoholic steatohepatitis (NASH) (n = 180)] were evaluated. Genomic DNA was extracted from peripheral blood cells, and polymorphisms in CYBA (unregistered) and NOX4 (rs3017887) were determined by direct sequencing of PCR. RESULTS: Associations of CYBA-675 T/A with high-density lipoprotein (HDL) (TT vs TA vs AA; P < 0.01) and triglycerides (TGL) (TT vs XA; P < 0.01) were observed only in NASH patients. For polymorphisms in the NOX4 gene, NOX4 (rs3017887) CA + AA genotypes was significant associated with alanine aminotransferase (ALT) (CA + AA vs CC; P = 0.02). However, there was no association of SNPs in the CYBA and NOX4 genes encoding the NADPH oxidase system proteins and the presence of NASH. Regarding the clinical results, it was observed that the most advanced degrees of fibrosis occurred in patients diagnosed with type 2 diabetes mellitus (66.9% vs 37.5%, P < 0.01) and those who were more obese (32.2 vs 29.0 kg/m2, P < 0.01). In addition, serum glucose and insulin levels increased significantly in the presence of NASH. CONCLUSIONS: There were associations between the presence of the allele A in the NOX4 SNP and a higher concentration of ALT in the NAFLD population; between the presence of the AA genotype in the polymorphism of the CYBA-675 T/A CYBA gene and a higher level of TGL and lower HDL in NASH patients. The presence of metabolic syndrome was associated with advanced degrees of fibrosis in NAFLD patients.

Non-pharmacological management options for MAFLD: a practical guide.

Lifestyle changes should be the main basis for any treatment for metabolic dysfunction-associated fatty liver disease (MAFLD), aiming to increase energy expenditure, reduce energy intake and improve the quality of nutrients consumed. As it is a multifactorial disease, approaches such as physical exercise, a better dietary pattern, and possible pharmacological intervention are shown to be more efficient when used simultaneously to the detriment of their applications. The main treatment for MAFLD is a lifestyle change consisting of diet, activity, exercise, and weight loss. The variables for training prescription such as type of physical exercise (aerobic or strength training), the weekly frequency, and the intensity most indicated for the treatment of MAFLD remain uncertain, that is, the recommendations must be adapted to the clinical conditions comorbidities, and preferences of each subject in a way individual. This review addresses recent management options for MAFLD including diet, nutrients, gut microbiota, and physical exercise.

PNPLA3 GENE POLYMORPHISM AND RED MEAT CONSUMPTION INCREASED FIBROSIS RISK IN NASH BIOPSY-PROVEN PATIENTS UNDER MEDICAL FOLLOW-UP IN A TERTIARY CENTER IN SOUTHWEST BRAZIL.

BACKGROUND: Recent studies show an increase in nonalcoholic fatty liver disease (NAFLD) in populations with higher consumption of red meat, processed and cooked at high temperatures. On the other hand, the single nucleotide polymorphism rs738409 in the Patatin-like phospholipase domain containing 3 (PNPLA3) gene has been implicated in susceptibility to NAFLD and liver fibrosis. However, the synergistic effect between red meat consumption and the PNPLA3 gene polymorphism in NAFLD has not yet been evaluated. OBJECTIVE: To evaluate the association between the presence of the polymorphism in the PNPLA3 gene and the consumption of macronutrients, including meat consumption and its cooking method among NAFLD patients. METHODS: This was a cross-sectional study with 91 patients diagnosed with NAFLD by liver biopsy with genotyping for the polymorphism in the PNPLA3 gene were included. The consumption of calories and macronutrients was verified using the semi-quantitative food frequency questionnaire and the specific questionnaire on meat consumption. PNPLA3 gene polymorphism was analyzed by real-time polymerase chain reaction (RT-PCR) and anthropometric evaluation was realized. RESULTS: The mean BMI was 32.38±4.58 kg/m² and the waist circumference was 107±10 cm. On liver biopsy, 42% of patients had significant fibrosis (F≥2). The odds ratio of F≥2 was 2.12 for the GG group and 1.54 for the CG group, compared to the CC group. The mean caloric intake was 1170±463.20 kcal/d. The odds ratio in the CC group concerning high red meat consumption in comparison to low consumption was 1.33. For white meat, the odds ratio was 0.8 when comparing high and low intake, also in the CC group. CONCLUSION: High red meat intake and PNPLA3 gene polymorphism seem to synergistically affect NAFLD and liver fibrosis, requiring confirmation in a larger number of patients and in different populations.

PRECLINICAL MODELS OF LIVER CÂNCER.

•In this review, we described different murine models of carcinogenesis: classic models, new transgenic and combined models, that reproduce the key points for HCC and CCA genesis allowing a better understanding of its genetic physiopathological, and environmental abnormalities. •Each model has its advantages, disadvantages, similarities, and differences with the corresponding human disease and should be chosen according to the specificity of the study. Ultimately, those models can also be used for testing new anticancer therapeutic approaches. •Cholangiocarcinoma has been highlighted, with an increase in prevalence. This review has an important role in understanding the pathophysiology and the development of new drugs. Background - This manuscript provides an overview of liver carcinogenesis in murine models of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA). Objective - A review through MEDLINE and EMBASE was performed to assess articles until August 2022.Methods - Search was conducted of the entire electronic databases and the keywords used was HCC, CCA, carcinogenesis, animal models and liver. Articles exclusion was based on the lack of close relation to the subject. Carcinogenesis models of HCC include HCC induced by senescence in transgenic animals, HCC diet-induced, HCC induced by chemotoxicagents, xenograft, oncogenes, and HCC in transgenic animals inoculated with B and C virus. The models of CCA include the use of dimethylnitrosamine (DMN), diethylnitrosamine (DEN), thioacetamide (TAA), and carbon tetrachloride (CCl4). CCA murine models may also be induced by: CCA cells, genetic manipulation, Smad4, PTEN and p53 knockout, xenograft, and DEN-left median bile duct ligation. Results - In this review, we described different murine models of carcinogenesis that reproduce the key points for HCC and CCA genesis allowing a better understanding of its genetic, physiopathological, and environmental abnormalities. Conclusion - Each model has its advantages, disadvantages, similarities, and differences with the corresponding human disease and should be chosen according to the specificity of the study. Ultimately, those models can also be used for testing new anticancer therapeutic approaches.

P53 and VEGF are promising biomarkers for sorafenib efficacy in an experimental model of NASH-related HCC.

The efficacy of systemic therapy for hepatocellular carcinoma (HCC) related to non-alcoholic steatohepatitis (NASH) is poorly understood. In this study we evaluated the effects of sorafenib based on the expression of molecular markers related to major hepatocarcinogenesis pathways and angiogenesis in a NASH-related HCC model. Forty male rats were submitted to NASH-HCC induction through the combination of a high-fat and choline deficient diet and diethylnitrosamine (100 mg/L) administration in the drinking water for 13 and 16 weeks. After the induction period, the rats received daily gavage administration of saline solution (control) or Sorafenib (5 mg/kg/day) for 3 weeks. Thereafter, the animals were euthanized and samples from liver nodules were collected for histopathological analysis and immunohistochemical assessment of HEP-PAR-1, glutamine-synthetase, VEGF, survivin, ß-catenin and p53. A semi-quantitative score was used for VEGF, survivin and ß-catenin analysis. For p53, the percentage of positive cells was determined. Results were processed by Wilcoxon's test or Student's t-test. Both protocols efficiently induced HCC, most of them being moderately to poorly differentiated. Sorafenib-treated animals showed a decreased expression of VEGF and p53 in HCCs generated at 13 weeks when compared to control animals (p = 0.03; p = 0.04, respectively). No significant difference in ß-catenin and survivin were observed. There was a significant decrease in VEGF and p53 expression when comparing the two control groups (13 vs. 16 weeks, p < 0.01). p53 and VEGF are promising biomarkers for assessment of efficacy of Sorafenib, whereas survivin and ß-catenin were not found useful. Decreased immunohistochemical expression of p53 and VEGF in the 16 week control group may indicate a different metabolic status of HCC.

Association of UCP3 Polymorphisms with Nonalcoholic Steatohepatitis and Metabolic Syndrome in Nonalcoholic Fatty Liver Disease Brazilian Patients.

Background: We investigated the possible association of uncoupling protein 3 gene (UCP3) single nucleotide polymorphisms (SNPs) with nonalcoholic steatohepatitis (NASH) and metabolic syndrome (MetS) in nonalcoholic fatty liver disease (NAFLD) Brazilian patients. Methods:UCP3 SNPs rs1726745, rs3781907, and rs11235972 were genotyped in 158 biopsy-proven NAFLD Brazilian patients. Statistics was performed with JMP, R, and SHEsis softwares. Results: The TT genotype of rs1726745 was associated with less occurrence of MetS (P = 0.006) and with lower body mass index (BMI) in the entire NAFLD sample (P = 0.01) and in the NASH group (P = 0.02). The rs1726745-T was associated with lower values of AST (P = 0.001), ALT (P = 0.0002), triglycerides (P = 0.01), and total cholesterol (P = 0.02) in the entire NAFLD sample. Between groups, there were lower values of aminotransferases strictly in individuals with NASH (AST, P = 0.002; ALT, P = 0.0007) and with MetS (AST, P = 0.002; ALT, P = 0.001). The rs3781907-G was associated with lower GGT elevation values in the entire NAFLD sample (P = 0.002), in the NASH group (P = 0.004), and with MetS group (P = 0.003) and with protection for advanced fibrosis (P = 0.01). The rs11235972-A was associated with lower GGT values in the entire NAFLD sample (P = 0.006) and in the NASH group (P = 0.01) and with MetS group (P = 0.005), with fibrosis absence (P = 0.01) and protection for advanced fibrosis (P = 0.01). The TAA haplotype was protective for NASH (P = 0.002), and TGG haplotype was protective for MetS (P = 0.01). Conclusion:UCP3 gene variants were associated with protection against NASH and MetS, in addition to lower values of liver enzymes, lipid profile, BMI and, lesser fibrosis severity in the studied population.

Hepatocellular carcinoma (HCC) in patients with Non-Alcoholic Fatty Liver Disease (NAFLD): screening, treatment and survival analysis in a Brazilian series.

OBJECTIVE: The aim of the present study was to evaluate the clinical features, Hepatocellular Carcinoma (HCC) screening, treatment modalities, and Overall Survival (OS) in a series of Non-Alcoholic Fatty Liver Disease-Related Hepatocellular Carcinoma (NAFLD-HCC) Brazilian patients. METHODS: This was a cross-sectional study at the Instituto do Cancer do Estado de São Paulo, at the Faculdade de Medicina da Universidade de São Paulo with the approval of the local research ethics committee. NAFLD patients with HCC diagnosed, from May 2010 to May 2019, were included. RESULTS: A total of 131 patients were included. Risk factors for NAFLD were present in 94.7% of the patients. Only 29% of patients were in the HCC screening program before diagnosis. HCC treatment was performed in 84.7% of patients. Cumulative survival at the end of the first year was 72%, second-year 52%, and fifth-year 32%. HCC screening before diagnosis was not significantly associated with higher cumulative survival. The independent factors associated with shorter general survival were BCLC C-D, p < 0.001, and the size of the largest nodule > 42 mm, p = 0.039. CONCLUSIONS: Although the efficacy of screening in our population regarding overall survival was hampered due to the sample size (29% had screening), BCLC stages C‒D and the size of the largest nodule larger than 42 mm were identified as independent factors of worse prognosis.

NAFLD in Polycystic Ovary Syndrome: Association with PNPLA3 and Metabolic Features.

Background: The aim of this study was to determine the frequency of the rs738409 polymorphism in the patatin-like phospholipase domain containing 3 (PNPLA3) gene in patients with polycystic ovary syndrome (PCOS) and its impact on nonalcoholic fatty liver disease (NAFLD) risk and severity. We also evaluated other risk factors associated with NAFLD and advanced fibrosis. Methods: This was a cross-sectional study involving 163 patients with PCOS at a tertiary center. Genotyping for the PNPLA3 polymorphism was undertaken using a TaqMan assay. The degree of fibrosis was defined by transient elastography. Results: The prevalence of NAFLD was 72.4%, and the polymorphism was heterozygous in 41.7% and homozygous in 8% of patients. Homeostasis model assessment of insulin resistance ≥ 2.5 was the main factor associated with the risk of developing NAFLD (OR = 4.313, p = 0.022), and its effect was amplified by the polymorphism (OR = 12.198, p = 0.017). Age > 32 years also conferred a higher risk for NAFLD. HDL values ≥ 50 mg/dL conferred protection against the outcome. Metabolic syndrome (OR = 13.030, p = 0.020) and AST > 32 U/L (OR = 9.039, p = 0.009) were independent risk factors for advanced fibrosis. Conclusions: In women with PCOS, metabolic characteristics are more relevant than PNPLA3 polymorphism regarding the risk for NAFLD and its advanced forms, but these factors can act synergistically, increasing disease risk.

Ability of a Combined FIB4/miRNA181a Score to Predict Significant Liver Fibrosis in NAFLD Patients.

Liver biopsy is the gold standard for assessing fibrosis, but there is a need to seek non-invasive biomarkers for this purpose. The aim of this study was to evaluate the correlation between the serum levels of the microRNAs miR-21, miR-29a, miR-122, miR-155 and miR-181a and the phenotypic expression of NAFLD. A cross-sectional study was carried out on 108 NAFLD patients diagnosed by liver biopsy. FIB-4 and NAFLD fibrosis scores were calculated. The comparison between the distributions of microRNA values according to the presence or absence of histological fibrosis (F2-F4) was performed. A multivariate logistic regression analysis was performed to build a score for predicting fibrosis using FIB-4 and Ln (miR-181a) as independent variables. Only miR-181a showed a statistical difference between patients with significant liver fibrosis (>F2) and those without (F0-F1) (p = 0.017). FIB-4 revealed an AUC on the ROC curve of 0.667 to predict clinically significant fibrosis (F2-F4). When assessed using the score in association with Ln (miR-181a), there was an improvement in the ROC curve, with an AUC of 0.71. miR-181a can be used as a non-invasive method of predicting fibrosis in NAFLD, and an association with FIB-4 has the potential to increase the accuracy of each method alone.

Fatty Pancreas: Disease or Finding?

Despite a growing number of investigative studies on pancreatic fat deposition, there remains no clear indication regarding the clinical relevance of fat infiltration in the pancreas, also called fatty pancreas (FP). An individual's body weight is correlated with their pancreatic weight. Moreover, lipid infiltration causes disorders that compromise not only morphology but also metabolic functions. Fat infiltration leads to insulin resistance, type II diabetes mellitus, and pancreatic cancer; however, knowledge about pancreatic fat content and aspects related to the clinical profile remains unclear in the literature. The present review describes the current knowledge of FP, including its pathophysiology and clinical implications, as well as lifestyle changes in FP.

Methylene tetrahydrofolate reductase (MTHFR) and vascular endothelial growth factor (VEGF) polymorphisms in Brazilian patients with Hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC).

OBJECTIVE: The folate pathway is involved in hepatic carcinogenesis and angiogenesis. Polymorphisms in genes related to such processes, including methylene tetrahydrofolate reductase (MTHFR) and vascular endothelial growth factor (VEGF)] may play an important role in the development of hepatocellular carcinoma (HCC). The objective of this study was to evaluate MTHFR and VEGF polymorphisms in Brazilian patients with hepatitis C virus (HCV)-related HCC. METHODS: A total of 119 patients diagnosed with confirmed HCC and HCV were included in the study. SNP genotyping assays were performed using real-time PCR. VEGFA (rs2010963, rs3025039, and rs833061) and MTHFRC677T (rs1801133, rs1801131) polymorphisms were evaluated. RESULTS: The C alleles of MTHFR (rs1801131) and VEGF (rs2010963) were associated with protection against the development of multinodular HCC, while the T allele of MTHFR (rs1801133) was associated with a higher risk of multinodular presentation [p=0.04 OR 1.835 CI (1.022-3.297)]. Multivariate analysis revealed that the GG/GC genotypes of VEGF rs2010963 were independently associated with multinodular tumors at diagnosis (p=0.013; OR 4.78 CI (1.38-16.67)]. CONCLUSION: Our results suggest that these polymorphisms may increase the risk of rapid tumor progression in patients with HCV infection. This subgroup of patients with HCC and who present polymorphism is more likely to be diagnosed with multinodular disease and not be amenable to receiving curative treatments. These data must be validated in larger cohorts, and the screening intervals can be customized based on genetic history.

Association of polymorphisms of glutamate-cystein ligase and microsomal triglyceride transfer protein genes in non-alcoholic fatty liver disease.

BACKGROUND AND AIMS: Although the metabolic risk factors for non-alcoholic fatty liver disease (NAFLD) progression have been recognized, the role of genetic susceptibility remains a field to be explored. The aim of this study was to examine the frequency of two polymorphisms in Brazilian patients with biopsy-proven simple steatosis or non-alcoholic steatohepatitis (NASH): -493 G/T in the MTP gene, which codes the protein responsible for transferring triglycerides to nascent apolipoprotein B, and -129 C/T in the GCLC gene, which codes the catalytic subunit of glutamate-cystein ligase in the formation of glutathione. METHODS: One hundred and thirty-one biopsy-proven NAFLD patients (n = 45, simple steatosis; n = 86, NASH) and 141 unrelated healthy volunteers were evaluated. Genomic DNA was extracted from peripheral blood cells, and the -129 C/T polymorphism of the GCLC gene was determined by restriction fragment length polymorphism (RFLP). The -493 G/T polymorphism of the MTP gene was determined by direct sequencing of the polymerase chain reaction products. RESULTS: The presence of at least one T allele in the -129 C/T polymorphism of the GCLC gene was independently associated with NASH (odds ratio 12.14, 95% confidence interval 2.01-73.35; P = 0.007), whereas, the presence of at least one G allele in the -493 G/T polymorphism of the MTP gene differed slightly between biopsy-proven NASH and simple steatosis. CONCLUSION: This difference clearly warrants further investigation in larger samples. These two polymorphisms could represent an additional factor for consideration in evaluating the risk of NAFLD progression. Further studies involving a larger population are necessary to confirm this notion.

The transcontinental variability of nonalcoholic fatty liver disease.

Aim: To compare the phenotype of lean versus overweight (OW) and obese (OB) subjects with non-alcoholic fatty liver disease (NAFLD) across multiple continents. Methods: A retrospective study of histologically defined subjects from a single center each in France (Fr), Brazil (Br), India (In) and United States (US) was performed. Results: A total of 70 lean [body mass index (BMI) < 25 kg/m2] subjects (Fr:Br:In:US: 16:19:22:13) with NAFLD were compared to 136 OW (BMI > 25 kg/m2, BMI < 29 kg/m2) (n = 28:33:52:23) and 224 OB subjects (BMI > 29 kg/m2) (n = 81:11:22:103). Lean French subjects had the lowest incidence of type 2 diabetes while those from Brazil (P < 0.01) had the highest. Lean subjects had similar low-density lipoprotein-cholesterol, but higher high-density lipoprotein-cholesterol compared to obese subjects in all regions. In both lean and obese subjects, there were both insulin-sensitive and insulin-resistant subjects. Lean French subjects were most insulin-sensitive while those from Brazil were mostly insulin-resistant. For each weight category, subjects from India were more insulin-sensitive than those from other regions. Disease activity increased from lean to overweight to obese in France but was similar across weight categories in other regions. Conclusion: The phenotype of NAFLD in lean subjects varies by region. Some obese subjects with NAFLD are insulin-sensitive. We hypothesize that genetics and region-specific disease modifiers account for these differences.

Effects of Aerobic Exercise Protocol on Genes Related to Insulin Resistance and Inflammation in the Pancreas of ob/ob Mice with NAFLD.

PURPOSE: To evaluate the effect of 8 weeks of aerobic training on insulin resistance and inflammatory response in obese mice (ob/ob) with NAFLD. MATERIALS AND METHODS: Male ob/ob mice were randomly divided into sedentary (n=7) and trained (n=7) groups. Aerobic training consisted of 5 weekly sessions, 60 min per session at 60% of the maximum speed of the running test. Hepatic and pancreatic samples were collected to evaluate histological features and gene expression associated with insulin resistance and inflammatory response after 8-week experiment protocol. RNA was performed by TRIzol®. PCR experiments were performed using the Rotor-Gene RG-3000. Parametric data were assessed by t-test, one-way ANOVA and Bonferroni test for multiple comparisons. Non-parametric data were assessed by the Mann-Whitney tests with Dunn's post-test of multiple comparisons. Histological analysis was assessed by chi-square test with Fisher's exact test. Significant variables were considered when p<0.05. All the analyses were performed by GraphPad Prism V6.0 software (GraphPad Software Inc.). RESULTS: Reductions in bodyweight (p = 0.008), weight evolution (p = 0.03), food intake (p <0.0001) and fat content were observed in trained group. Moreover, the trained group showed better results in peak velocity (p=0.03) physical effort tolerance (p=0.006) and distance (p=0.01). Gene expression showed differences in IL-10 (p=0.03) and GLUT-2 (p=0.03) in hepatic analysis, between groups. Pancreatic gene expression showed difference between groups in IRS-2 (p=0.004), GLUT-2 (p=0.03) and IL-10 (p=0.008) analysis. Also, the trained group showed lower values for interlobular fat and inflammatory infiltrate in histological analysis when compared to sedentary animals. CONCLUSION: An 8-week physical training protocol was able to attenuate bodyweight gain, food intake and generate positive effects on gene expression related to insulin resistance and inflammation in both liver and pancreas of ob/ob mice.