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.

Hypolactasia is associated with insulin resistance in nonalcoholic steatohepatitis.

AIM: To assess lactase gene (LCT)-13910C>T polymorphisms in Brazilian non-alcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) patients in comparison with healthy controls. METHODS: This was a transverse observational clinical study with NAFLD patients who were followed at the Hepatology Outpatient Unit of the Hospital das Clínicas, São Paulo, Brazil. The polymorphism of lactase non-persistence/lactase persistence (LCT-13910C>T) was examined by PCR-restriction fragment length polymorphism technique in 102 liver biopsy-proven NAFLD patients (steatosis in 9 and NASH in 93) and compared to those of 501 unrelated healthy volunteers. Anthropometric, clinical, biochemical and liver histology data were analyzed. Continuous variables were compared using the t or Mann-Whitney tests, and categorical data were compared with the Fisher's exact test. Univariate logistic regression and multivariate logistic regression adjusted for gender and age were performed. RESULTS: No differences in the LCT-13910 genotype frequencies were noted between the NAFLD patients (66.67% of the patients with steatosis were CC, 33.33% were CT, and none were TT; 55.91% of the patients with NASH were CC, 39.78% were CT, and 4.3% were TT; P = 0.941) and the healthy controls (59.12% were CC, 35.67% were CT, and 5.21% were TT) or between the steatosis and NASH patients. That is, the distribution of the lactase non-persistence/lactase persistence polymorphism (LCT-13910C>T) in the patients with NAFLD was equal to that in the general population. In the NASH patients, the univariate analysis revealed that the lactase non-persistence (low lactase activity or hypolactasia) phenotype was associated with higher insulin levels (23.47 ± 15.94 µU/mL vs 15.8 ± 8.33 µU/mL, P = 0.027) and a higher frequency of insulin resistance (91.84% vs 72.22%, P = 0.02) compared with the lactase persistence phenotype. There were no associations between the LCT genotypes and diabetes (P = 0.651), dyslipidaemia (P = 0.328), hypertension (P = 0.507) or liver histology in these patients. Moreover, in the NASH patients, hypolactasia was an independent risk factor for insulin resistance even after adjusting for gender and age [OR = 5.0 (95%CI: 1.35-20; P = 0.017)]. CONCLUSION: The LCT-13910 genotype distribution in Brazilian NAFLD patients was the same as that of the general population, but hypolactasia increased the risk of insulin resistance in the NASH patients.

Genetic ancestry analysis in non-alcoholic fatty liver disease patients from Brazil and Portugal.

AIM: To study the association between genetic ancestry, non-alcoholic fatty liver disease (NAFLD) metabolic characteristics in two cohorts of patients, from Brazil and Portugal. METHODS: We included 131 subjects from Brazil [(n = 45 with simple steatosis (S. Steatosis) and n = 86 with nonalcoholic steatohepatitis (NASH)] and 90 patients from Portugal (n = 66, S. Steatosis; n = 24, NASH). All patients had biopsy-proven NAFLD. In histologic evaluation NAFLD activity score was used to assess histology and more than 5 points defined NASH in this study. Patients were divided into two groups according to histology diagnosis: simple steatosis or non-alcoholic statohepatitis. Genetic ancestry was assessed using real-time polymerase chain reaction. Seven ancestry informative markers (AT3-I/D, LPL, Sb19.3, APO, FY-Null, PV92, and CKMM) with the greatest ethnic-geographical differential frequencies (≥ 48%) were used to define genetic ancestry. Data were analyzed using R PROJECTS software. Ancestry allele frequencies between groups were analyzed by GENEPOP online and the estimation of genetic ancestry contribution was evaluated by ADMIX-95 software. The 5% alpha-error was considered as significant (P < 0.05). RESULTS: In the Brazilian sample, NASH was significantly more frequent among the elderly patients with diabetes (NASH 56 ± 1.1 years old vs S. Steatosis 51 ± 1.5 years old, P = 3.7 x 10(-9)), dyslipidemia (NASH 63% vs S. Steatosis 37%, P = 0.009), higher fasting glucose levels (NASH 124 ± 5.2 vs S. Steatosis 106 ± 5.3, P = 0.001) and Homeostatic Model of Assessment index > 2.5 [NASH 5.3 (70.8%) vs S. Steatosis 4.6 (29.2%) P = 0.04]. In the Portuguese study population, dyslipidemia was present in all patients with NASH (P = 0.03) and hypertension was present in a larger percentage of subjects in the S. Steatosis group (P = 0.003, respectively). The genetic ancestry contribution among Brazilian and Portuguese individuals with NASH was similar to those with S. Steatosis from each cohort (Brazilian cohort: P = 0.75; Portuguese cohort: P = 0.97). Nonetheless, the genetic ancestry contribution of the Brazilian and Portuguese population were different, and a greater European and Amerindian ancestry contribution was detected in the Portuguese population while a higher African genetic ancestry contribution was observed in Brazilian population of both NASH and S. Steatosis groups. CONCLUSION: There was no difference between the genetic ancestry contribution among Brazilian and Portuguese individuals with NASH and S. Steatosis from each cohort.

Hypocaloric high-protein diet improves clinical and biochemical markers in patients with nonalcoholic fatty liver disease (NAFLD).

OBJECTIVE: To investigate the role of hypocaloric highprotein diet, a prospective clinical study was conducted in NAFLD patients. RESEARCH METHODS AND PROCEDURES: Pre-versus post-interventional data were analyzed in 48 stable NAFLD patients (submitted to a hypocaloric high-protein diet during 75 days. Variables included anthropometrics (body mass index/ BMI and waist circumference/WC), whole-body and segmental bioimpedance analysis and biochemical tests. Diet compliance was assessed by interviews every two weeks. RESULTS: BMI, WC and body fat mass remained relatively stable (-1.3%, -1.8% and -2.5% respectively, no significance). HDL- cholesterol increased (P < 0.05) whereas total, LDL and VLDL cholesterol, triglycerides, aspartate aminotransferase/ AST, gamma glutamyltransferase/GGT, alkaline phosphatase/ AP, fasting blood glucose and glycated hemoglobin/ HbA1c decreased (P < 0.05). When patients were stratified according to increase (22/48, 45.8%) and decrease (21/48, 43.8%) of BMI, association between weight decrease and liver benefit could be elicited in such circumstances for ALT, AP and AST/ALT ratio. No change could be demonstrated in patients who gained weight. Multivariate assessment confirmed that waist circumference, ferritin, triacylglycerol, and markers of glucose homeostasis were the most relevant associated with liver enzymes. DISCUSSION: Ours results are consistent with the literature of calorie restriction in the management of NAFLD. Changes in lifestyle and weight loss are recommended for NAFLD patients. European guidelines also support this recommendation. CONCLUSION: This is the first study that demonstrated that a high protein, hypocaloric diet were associated with improvement of lipid profile, glucose homeostasis and liver enzymes in NAFLD independent on BMI decrease or body fat mass reduction.

Hypocaloric high-protein diet improves clinical and biochemical markers in patients with nonalcoholic fatty liver disease (NAFLD) / La dieta hipocalórica rica en proteínas mejora los marcadores clínicos y bioquímicos en pacientes con hepatopatía grasa no alcohólica (HPGNA)

Objective: To investigate the role of hypocaloric high-protein diet, a prospective clinical study was conducted in NAFLD patients. Research methods and procedures: Pre-versus post-interventional data were analyzed in 48 stable NAFLD patients (submitted to a hypocaloric high-protein diet during 75 days. Variables included anthropometrics (body mass index/ BMI and waist circumference/WC), whole-body and segmental bioimpedance analysis and biochemical tests. Diet compliance was assessed by interviews every two weeks. Results: BMI, WC and body fat mass remained relatively stable (-1.3%, -1.8% and -2.5% respectively, no significance). HDL- cholesterol increased (P < 0.05) whereas total, LDL and VLDL cholesterol, triglycerides, aspartate aminotransferase/AST, gamma glutamyltransferase/GGT, alkaline phosphatase/AP, fasting blood glucose and glycated hemoglobin/ HbA1c decreased (P < 0.05). When patients were stratified according to increase (22/48, 45.8%) and decrease (21/48, 43.8%) of BMI, association between weight decrease and liver benefit could be elicited in such circumstances for ALT, AP and AST/ALT ratio. No change could be demonstrated in patients who gained weight. Multivariate assessment confirmed that waist circumference, ferritin, triacylglycerol, and markers of glucose homeostasis were the most relevant associated with liver enzymes. Discussion: Ours results are consistent with the literature of calorie restriction in the management of NAFLD. Changes in lifestyle and weight loss are recommended for NAFLD patients. European guidelines also support this recommendation. Conclusion: This is the first study that demonstrated that a high protein, hypocaloric diet were associated with improvement of lipid profile, glucose homeostasis and liver enzymes in NAFLD independent on BMI decrease or body fat mass reduction (AU)

Objetivo: Para investigar el papel de la dieta hipocalórica rica en proteínas, se realizó un estudio clínico prospectivo en pacientes con HPGNA. Métodos de investigación y procedimientos: Se analizaron los datos antes y después de la intervención en 48 pacientes con HPGNA estable, sometidos a una dieta hipocalórica y rica en proteínas durante 75 días. Las variables incluían medidas antropométricas (índice de masa corporal (IMC) y circunferencia de la cintura (CC)), análisis de bioimpedancia corporal completa y segmentaria y pruebas bioquímicas. El cumplimiento de la dieta se evaluó mediante entrevistas quincenales. Resultados: El IMC, la CC y la masa grasa corporal permanecieron relativamente estables (-1,3 %, -1,8 % y -2,5%, respectivamente, sin significación). Las HDL-colesterol aumentaron (P < 0,05) mientras que el colesterol total, las LDL y las VLDL, los triglicéridos, la aspartato aminotransferasa (AST), la gamma glutamiltransferasa (GGT), la fosfatasa alcalina (FA), la glucemia en ayunas y la hemoglobina glucosilada (HbA1c) disminuyeron (P < 0,05). Cuando se estratificó a los pacientes en función del aumento (22/48, 45,8 %) o descenso (21/48, 43,8 %) del IMC, se pudo observar una asociación entre la pérdida de peso y el beneficio hepático reflejado en la ALT, la FA y el cociente AST/ALT. No se pudo demostrar ningún cambio en los pacientes que ganaron peso. La evaluación multivariada confirmó que la circunferencia de la cintura, la ferritina, el triacilglicerol y los marcadores de la homeostasis de la glucosa eran los que más relevantemente se asociaban con las enzimas hepáticas. Discusión: Nuestros resultados son consistentes con la bibliografía relativa a la restricción calórica en el manejo de la HPGNA. Los cambios en el estilo de vida y la pérdida de peso se recomiendan en los pacientes con HPGNA. Las guías europeas también apoyan esta recomendación. Conclusión: Éste es el primer estudio que demuestra que una dieta rica en proteínas se asocia con la mejora del perfil lipídico, la homeostasis de la glucosa y las enzimas hepáticas en la HPGNA independientemente del descenso del IMC o la reducción de la masa grasa corporal (AU)

S-nitroso-N-acetylcysteine attenuates liver fibrosis in experimental nonalcoholic steatohepatitis.

S-Nitroso-N-acetylcysteine (SNAC) is a water soluble primary S-nitrosothiol capable of transferring and releasing nitric oxide and inducing several biochemical activities, including modulation of hepatic stellate cell activation. In this study, we evaluated the antifibrotic activity of SNAC in an animal model of nonalcoholic steatohepatitis (NASH) induced in Sprague-Dawley rats fed with a choline-deficient, high trans fat diet and exposed to diethylnitrosamine for 8 weeks. The rats were divided into three groups: SNAC, which received oral SNAC solution daily; NASH, which received the vehicle; and control, which received standard diet and vehicle. Genes related to fibrosis (matrix metalloproteinases [MMP]-13, -9, and -2), transforming growth factor ß-1 [TGFß-1], collagen-1α, and tissue inhibitors of metalloproteinase [TIMP-1 and -2] and oxidative stress (heat-shock proteins [HSP]-60 and -90) were evaluated. SNAC led to a 34.4% reduction in the collagen occupied area associated with upregulation of MMP-13 and -9 and downregulation of HSP-60, TIMP-2, TGFß-1, and collagen-1α. These results indicate that oral SNAC administration may represent a potential antifibrotic treatment for NASH.

Circulating levels of citrullinated and MMP-degraded vimentin (VICM) in liver fibrosis related pathology.

AIM: To investigate whether increased levels of vimentin citrullinated peptides identified by MS in articular cartilage can be measured in pathologies other than rheumatoid arthritis and be utilised for diagnostic purposes. METHODS: A monoclonal antibody against the sequence RLRSSVPGV-citrulline (VICM) was developed and evaluated in a carbon tetrachloride (CCl(4)) (n=52 + 28 controls) rat model of liver fibrosis and two clinical cohorts of adult patients with hepatitis C (HCV) (n=92) and non-alcoholic fatty liver disease (NAFLD) (n=62), and compared to healthy controls. RESULTS: In CCl(4)-treated rats, mean systemic VICM levels increased 31% at week 12 (176 ng/mL, P<0.001), 41.7% at weeks 16 (190 ng/mL, P<0.001), 49.2% at weeks 20 (200 ng/ml, P<0.001), compared to controls (134 ng/mL). VICM levels correlated with total hepatic collagen determined by Sirius red staining of rat livers (r=0.75, P<0.05). In the HCV cohort, when stratified according to the METAVIR F score, VICM levels were 63% higher in F0 (632 ng/mL ±75, p<0.05), 54% in F1 (597 ng/mL ±41.3, p<0.05) and 62% in F2 (628 ng/mL ±59, p<0.05) all compared to controls. In the NAFLD cohort, VICM levels were 20.6% higher in F0 (339 ±12 ng/mL, P<0.05), 23.8% in F1 (348 ±12 ng/mL, P<0.05) and 28.8% in F2 (362 ±25 P<0.05). CONCLUSION: We demonstrated increased serological levels of citrullinated and MMP degraded vimentin in an animal model of liver fibrosis and in early fibrosis associated with HCV and NAFLD patients. These data suggest that citrullinated and MMP degraded proteins are also present in liver fibrosis.

Gluco-lipidic indices in treated hypothyroidism associated with nonalcoholic fatty liver disease.

CONTEXT: Thyroid hormones may interfere with regulation of lipid and carbohydrate metabolism as well as with severity of nonalcoholic fatty liver disease (NAFLD), however results are still debated. OBJECTIVES: Retrospective evaluation of clinical and metabolic correlations between hypothyroidism and NAFLD was the target. METHODS: Clinical, biochemical and histological investigation of 103 NAFLD patients exhibiting drug-treated hypothyroidism was conducted. RESULTS: Steatosis was present in 32.0% of the population and nonalcoholic steatohepatitis in 68.0%. Females were the majority in both groups, with age of 50.0 ± 1.5 and 56.0 ± 1.1 years, respectively. Hypothyroidism was not rare (15.5%), and multivariate analysis confirmed positive correlation with this disease for insulin (r = 0.213, P = 0.03), glucose homeostasis index "HOMA" (r = 0.221, P = 0.02), aspartate aminotransferase (r = 0.234, P = 0.01) and triglycerides above 150 mg/dL (r = 0.233, P = 0.01). No association between hypothyroidism and steatohepatitis could be established. CONCLUSION: A link could be identified between hypothyroidism and markers of glucose and lipid homeostasis, but not with severity of NAFLD. The lack of correlation with liver biopsy requires further studies.

Gluco-lipidic indices in treated hypothyroidism associated with nonalcoholic fatty liver disease / Índices glicolipídicos no hipotireoidismo tratado associado à doença hepática gordurosa não-alcoólica

CONTEXT: Thyroid hormones may interfere with regulation of lipid and carbohydrate metabolism as well as with severity of nonalcoholic fatty liver disease (NAFLD), however results are still debated. OBJECTIVES: Retrospective evaluation of clinical and metabolic correlations between hypothyroidism and NAFLD was the target. METHODS: Clinical, biochemical and histological investigation of 103 NAFLD patients exhibiting drug-treated hypothyroidism was conducted. RESULTS: Steatosis was present in 32.0 percent of the population and nonalcoholic steatohepatitis in 68.0 percent. Females were the majority in both groups, with age of 50.0 ± 1.5 and 56.0 ± 1.1 years, respectively. Hypothyroidism was not rare (15.5 percent), and multivariate analysis confirmed positive correlation with this disease for insulin (r = 0.213, P = 0.03), glucose homeostasis index "HOMA" (r = 0.221, P = 0.02), aspartate aminotransferase (r = 0.234, P = 0.01) and triglycerides above 150 mg/dL (r = 0.233, P = 0.01). No association between hypothyroidism and steatohepatitis could be established. CONCLUSION: A link could be identified between hypothyroidism and markers of glucose and lipid homeostasis, but not with severity of NAFLD. The lack of correlation with liver biopsy requires further studies.

CONTEXTO: Os hormônios tireoidianos podem interferir na regulação do metabolismo de lipídios e carboidratos e também na gravidade da doença hepática gordurosa não-alcoólica (DHGNA), porém os resultados ainda são debatidos. OBJETIVOS: Avaliar retrospectivamente correlações clínicas e metabólicas entre hipotireoidismo e DHGNA. MÉTODOS: Em 103 pacientes com DHGNA confirmada por biopsia e também hipotireoidismo recebendo tratamento, procedeu-se à investigação clínica, bioquímica e histológica. RESULTADOS: A esteatose foi observada em 32,0 por cento e a esteatohepatite não-alcoólica em 68,0 por cento da população. O sexo feminino foi mais frequente nas duas circunstâncias, com idade média de 50,0 ± 1,5 e 56,0 ± 1,1 anos, respectivamente. O hipotireoidismo não foi raro (15,5 por cento), sendo que na análise multivariada insulina (r = 0,213, P = 0,03), índice de homeostase glicídica HOMA (r = 0,221, P = 0,02), aspartato aminotransferase (r = 0,234, P = 0,01) e triglicerídeos acima de 150 mg/dL (r = 0,233, P = 0,01) foram correlacionados positivamente com hipotireoidismo. A associação entre hipotireoidismo e esteatohepatite não pôde ser estabelecida neste estudo. CONCLUSÃO: O hipotireoidismo vinculou-se à piora de alguns marcadores do metabolismo glicolipídico, porém não a lesões histológicas mais avançadas. A falta de correlação com a biopsia do fígado requer maiores estudos.

Pro- and anti-inflammatory cytokines in steatosis and steatohepatitis.

BACKGROUND: Fatty liver disease is a problem in both bariatric patients and in patients with moderate obesity. Tumor necrosis factor (TNF)-alpha has been frequently measured in nonalcoholic steatohepatitis (NASH) with or without diabetes, but less is known about interleukin (IL)-6 and IL-10. METHODS: Moderately obese patients (n = 80) with histologically proven steatosis (n = 29) and NASH (n = 51) were recruited. Serum levels of cytokines were documented along with clinical information. The aim was to identify the correlates of such biomolecules in a stable population. RESULTS: Diabetes tended to be more associated with NASH (52.5% instead of 41.4%, P = 0.015), with no difference of age, gender, or body mass index regarding steatosis. For the entire population, cytokine changes were not significant, including TNF-alpha and IL-6. In diabetics only, all markers tended to diminish with NASH, especially IL-10 (P = 0.000). IL-10 correlated with homeostatic model assessment index (P = 0.000) and other variables of glucose homeostasis in diabetes, thus representing a major marker of the disease. CONCLUSIONS: (1) Generally inconsistent changes in pro- and anti-inflammatory cytokines occurred when NASH was globally compared to steatosis. (2) In contrast, downregulation of IL-6 and IL-10 was perceived in diabetics with NASH. (3) Arterial hypertension did not play a role in these circumstances. (4) IL-10 maintained strong correlations with glucose metabolism indices. (5) TNF-alpha could not be incriminated for progressive liver damage, as values failed to increase in NASH. (6) Investigations of IL-10 and other counterregulatory cytokines are lacking in this context and deserve further studies.