Mitochondrial Alterations in Nonalcoholic Fatty Liver Disease. Pediatric Case Description of Three Submitted Sequential Biopsies

Nonalcoholic fatty liver disease (NAFLD) is a clinical-pathological syndrome that encompasses a wide spectrum of morphologic alterations, ranging from simple hepatic steatosis to a more severe stage, known as nonalcoholic steatohepatitis (NASH). The purpose of this clinical report was to contribute to the understanding of mitochondrial alterations in NAFLD. The child (13-month-old) underwent initial biopsy in the year 2000 and was diagnosed with diffuse macro and microvesicular steatosis. Two additional biopsies were performed in 2001 and 2004. A high percentage of microvesicular steatosis was observed in the biopsies performed in 2000 and 2001. Mitochondrial size was slightly increased in the biopsy performed in the year 2000, significantly increased in 2001 and decreased in 2004. The presence of "mitochondrial hypertrophy" in the hepatocytes of an asymptomatic pediatric patient whose disease presentation was typical of NAFLD, excluding other pathological processes, allowed us to suspect that such a defect was considered the primary mitochondrial disorder.

Nonalcoholic fatty liver disease and metabolic syndrome in postmenopausal women

Nonalcoholic fatty liver disease (NAFLD) is considered the most common cause of chronic liver disease in the Western countries. NAFLD includes a spectrum ranging from a simple steatosis to a nonalcoholic steatohepatitis (NASH) which is defined by the presence of inflammatory infiltrate, cellular necrosis, hepatocyte ballooning, and fibrosis and cirrhosis that can eventually develop into hepatocellular carcinoma. Studies emphasize the role of insulin resistance, oxidative stress, pro-inflammatory cytokines, adipokines in the development and progression of NAFLD. It seems to be independently associated with type II diabetes mellitus, increased triglycerides, decreased HDL-cholesterol, abdominal obesity and insulin resistance. These findings are in accordance with the criteria used in the diagnosis of metabolic syndrome (MetS). Here, we will discuss the current knowledge on the epidemiology, pathophysiology and diagnosis of NAFLD and the association of metabolic syndrome in postmenopausal women.

Evaluation of Clinical and Inflammatory Markers of Nonalcoholic Fatty Liver Disease in Postmenopausal Women with Metabolic Syndrome

Background: The aim of this study was to assess clinical and inflammatory markers in nonalcoholic fatty liver disease (NAFLD) in postmenopausal women with metabolic syndrome.Methods: This cross-sectional study included 180 Brazilian women (age >= 45 years and amenorrhea >= 12 months). Metabolic syndrome was diagnosed by the presence of at least three of the following indicators: Waist circumference (WC) > 88 cm, triglycerides (TGs) >= 150 mg/dL, high-density lipoprotein (HDL) < 50 mg/dL; blood pressure >= 130/85 mmHg; and glucose >= 100 mg/dL. NAFLD was diagnosed by abdominal ultrasound. Participants were divided into three groups: Metabolic syndrome alone (n = 53); metabolic syndrome + NAFLD (n = 67); or absence of metabolic syndrome or NAFLD (control, n = 60). Clinical, anthropometric, and biochemical variables were quantified. The inflammatory profile included adiponectin, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha). Data were submitted to statistical analysis using a Tukey test, analysis of variance (ANOVA), chi-squared, Pearson correlation, and logistic regression (odds ratio, OR).Results: Women with metabolic syndrome + NAFLD, abdominal obesity, high glucose, and insulin resistance by HOMA-IR were compared to women with metabolic syndrome alone and controls (P < 0.05). High values of IL-6 and TNF-alpha and low values of adiponectin were observed among women with metabolic syndrome alone or metabolic syndrome + NAFLD when compared to controls (P < 0.05). In multivariate analysis, the variables considered as risk of NAFLD development were: High systolic blood pressure (SBP) [(OR 1.02, 95% confidence interval (CI) 1.0-1.04]; large WC (OR 1.07, 95% CI 1.01-1.13); insulin resistance (OR 3.81, 95% CI 2.01-7.13); and metabolic syndrome (OR 8.68, 95% CI 3.3-24.1). Adiponectin levels reduced NAFLD risk (OR 0.88, 95% CI 0.80-0.96).Conclusion: In postmenopausal women, metabolic syndrome, abdominal obesity, and insulin resistance were risk markers for the development of NAFLD, whereas higher adiponectin values indicated a protection marker.

Clinical Predictors of Different Grades of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is one of the comorbidities related to obesity. Liver biopsy has been used as the "gold standard" for the diagnosis, grading, and prognosis of obese patients. The objective of the present study was to evaluate clinical predictors of more advanced stages of NAFLD. In this retrospective study we assessed several physical and laboratorial factors, including some cytokines, in morbidly obese patients submitted to Roux-en-Y gastric bypass that could be related to the diagnosis and staging of NAFLD. Fragments of the livers were obtained from wedge biopsies during operation. The medical records of 259 patients were studied. The patients were divided into four groups: normal hepatic biopsy, steatosis, mild nonalcoholic steatohepatitis (NASH), and moderate and severe NASH. There were no differences in cytokine levels among groups. The triglyceride levels were the only variable that could stratify the grades of NAFLD and also differentiate from normal livers in the female patients. Also in this group, the aminotransferases and GGT levels and fasting glucose were predictors of the more advanced stages of NASH, while BMI and weight were predictors of the more advanced stages of NASH in male patients. There are no available markers in clinical practice to detect the initial stages of NAFLD. It is very important to perform a liver biopsy in all patients submitted to bariatric surgery and in obese patients with no indication to be operated in the presence of elevated blood levels of aminotransferases, GGT, and fasting glucose.

Vitamin C and Vitamin E in Prevention of Nonalcoholic Fatty Liver Disease (NAFLD) in Choline Deficient Diet Fed Rats

Abstract Aim Oxidative stress has been implicated in the pathogenesis of Nonalcoholic Fatty Liver Disease (NAFLD). Vitamin C and vitamin E are known to react with reactive oxygen species (ROS) blocking the propagation of radical reactions in a wide range of oxidative stress situations. The potential therapeutic efficacy of antioxidants in NAFLD is unknown. The aim of this study was to evaluate the role of antioxidant drugs (vitamin C or vitamin E) in its prevention. Methods Fatty liver disease was induced in Wistar rats by choline-deficient diet for four weeks. The rats were randomly assigned to receive vitamin E (n = 6) – (200 mg/day), vitamin C (n = 6) (30 mg/Kg/day) or vehicle orally. Results In the vehicle and vitamin E-treated rats, there were moderate macro and microvesicular fatty changes in periportal area without inflammatory infiltrate or fibrosis. Scharlach stain that used for a more precise identification of fatty change was strong positive. With vitamin C, there was marked decrease in histological alterations. Essentially, there was no liver steatosis, only hepatocellular ballooning. Scharlach stain was negative. The lucigenin-enhanced luminescence was reduced with vitamin C (1080 ± 330 cpm/mg/minx103) as compared to those Vitamin E and control (2247 ± 790; 2020 ± 407 cpm/mg/minx103, respectively) (p < 0.05). Serum levels of aminotransferases were unaltered by vitamin C or vitamin E. Conclusions 1) Vitamin C reduced oxidative stress and markedly inhibited the development of experimental liver steatosis induced by choline-deficient diet ; 2)Vitamin E neither prevented the development of fatty liver nor reduced the oxidative stress in this model.

A role for low hepatic copper concentrations in nonalcoholic Fatty liver disease

Copper has a role in antioxidant defense, lipid peroxidation, and mitochondrial function, and copper deficiency has been linked to atherogenic dyslipidemia. We aimed to investigate the potential role of copper availability in the pathogenesis of nonalcoholic fatty liver disease (NAFLD).

Cardiovascular risk factors and the metabolic syndrome in pediatric nonalcoholic fatty liver disease

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD), the most common cause of liver disease in children, is associated with obesity and insulin resistance. However, the relationship between NAFLD and cardiovascular risk factors in children is not fully understood. The objective of this study was to determine the association between NAFLD and the presence of metabolic syndrome in overweight and obese children. METHODS AND RESULTS: This case-control study of 150 overweight children with biopsy-proven NAFLD and 150 overweight children without NAFLD compared rates of metabolic syndrome using Adult Treatment Panel III criteria. Cases and controls were well matched in age, sex, and severity of obesity. Children with NAFLD had significantly higher fasting glucose, insulin, total cholesterol, low-density lipoprotein cholesterol, triglycerides, systolic blood pressure, and diastolic blood pressure than overweight and obese children without NAFLD. Subjects with NAFLD also had significantly lower high-density lipoprotein cholesterol than controls. After adjustment for age, sex, race, ethnicity, body mass index, and hyperinsulinemia, children with metabolic syndrome had 5.0 (95% confidence interval, 2.6 to 9.7) times the odds of having NAFLD as overweight and obese children without metabolic syndrome. CONCLUSIONS: NAFLD in overweight and obese children is strongly associated with multiple cardiovascular risk factors. The identification of NAFLD in a child should prompt global counseling to address nutrition, physical activity, and avoidance of smoking to prevent the development of cardiovascular disease and type 2 diabetes.

Copper availability contributes to iron perturbations in human nonalcoholic fatty liver disease

BACKGROUND ; AIMS: Iron perturbations are frequently observed in nonalcoholic fatty liver disease (NAFLD). We aimed to investigate a potential association of copper status with disturbances of iron homeostasis in NAFLD. METHODS: We retrospectively studied 140 NAFLD patients and 25 control subjects. Biochemical and hepatic iron and copper parameters were analyzed. Hepatic expression of iron regulatory molecules was investigated in liver biopsy specimens by reverse-transcription polymerase chain reaction and Western blot analysis. RESULTS: NAFLD patients had lower hepatic copper concentrations than control subjects (21.9 +/- 9.8 vs 29.6 +/- 5.1 microg/g; P = .002). NAFLD patients with low serum and liver copper concentrations presented with higher serum ferritin levels (606.7 +/- 265.8 vs 224.2 +/- 176.0 mg/L; P < .001), increased prevalence of siderosis in liver biopsy specimens (36/46 vs 10/47 patients; P < .001), and with elevated hepatic iron concentrations (1184.4 +/- 842.7 vs 319.9 +/- 451.3 microg/g; P = .020). Lower serum concentrations of the copper-dependent ferroxidase ceruloplasmin (21.7 +/- 4.1 vs 30.4 +/- 6.4 mg/dL; P < .001) and decreased liver ferroportin (FP-1; P = .009) messenger RNA expression were found in these patients compared with NAFLD patients with high liver or serum copper concentrations. Accordingly, in rats, a reduced dietary copper intake was paralleled by a decreased hepatic FP-1 protein expression. CONCLUSIONS: A significant proportion of NAFLD patients should be considered copper deficient. Our results indicate that copper status is linked to iron homeostasis in NAFLD, suggesting that low copper bioavailability causes increased hepatic iron stores via decreased FP-1 expression and ceruloplasmin ferroxidase activity thus blocking liver iron export in copper-deficient subjects.

The Interactions of Nonalcoholic Fatty Liver Disease and Cardiovascular Diseases

A complex interaction among metabolic factors, adipose tissue lipolysis, oxidative stress, and insulin resistance results in a deleterious process that may link nonalcoholic fatty liver disease (NAFLD) with severe cardiovascular (CV) outcomes. Patients with NAFLD are at higher risk of atherosclerosis, new onset of CV events, and overall mortality. The strong association between NAFLD and CV disease should affect clinical practice, with screening and surveillance of patients with NAFLD. This review discusses the data linking these major diseases.

Nonalcoholic Fatty Liver Disease-Related Hepatocellular Carcinoma: A Problem of Growing Magnitude.

Hepatocellular carcinoma (HCC) is a cancer with globally rising incidence. Growing evidence supports associations between metabolic syndrome and diabetes as well as obesity and HCC arising in patients with nonalcoholic fatty liver disease (NAFLD). This constitutes a problem of alarming magnitude given the rising epidemic of these conditions. The role of diabetes seems to be particularly important when associated with obesity or cirrhosis. Excess hepatic iron may be another potential risk factor for the development of NAFLD-associated HCC. In the context of NAFLD, HCC frequently develops in a not-yet cirrhotic liver. As there are no surveillance programs for these patients, diagnosis often occurs at a tumor stage beyond curative options. Clinical, tumor, and patient characteristics in NAFLD-associated HCC differ from other etiologies. Older age and cardiovascular comorbidities may limit treatment options further. The outcome in patients with NAFLD-associated early HCC is excellent and therefore aggressive treatment should be pursued in appropriate patients. Population-based prevention to reduce the culprit-NAFLD-early recognition through targeted surveillance programs in risk-stratified patients and effective treatment of HCC associated with NAFLD are urgently needed. In this review, the authors summarize the epidemiology, risk factors, features, and prevention of NAFLD-associated HCC.

Nonalcoholic fatty liver disease: is all the fat bad?

Nonalcoholic fatty liver disease is now a major cause of liver disease in developed countries, largely as a result of an epidemic of obesity, diabetes and sedentary lifestyles. This has resulted in raised clinical awareness and diagnostic refinement. The entity encompasses several histologic patterns from benign steatosis to nonalcoholic steatohepatitis, the latter having a significant risk of progressive fibrosis and the development of cirrhosis. Labor-atory tests and imaging are not able to distinguish steatosis from steatohepatitis, which requires liver biopsy. However following an assessment of several risk factors, patients can be stratified for the potential risk of fibrosis, allowing the rational use of liver biopsy. This review will describe the various patterns of nonalcoholic fatty liver disease and relate this to disease pathogenesis and progression. Strategies for management, including experimental interventions, will be discussed.

Implication of gut microbiota in nonalcoholic fatty liver disease

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