Identifying non-alcoholic fatty liver disease among asymptomatic overweight and obese individuals by clinical and biochemical characteristics

Deficiency of ADAR2 ameliorates metabolic-associated fatty liver disease via AMPK signaling pathways in obese mice

Non-alcoholic fatty liver disease (NAFLD) is a chronic disease caused by hepatic steatosis. Adenosine deaminases acting on RNA (ADARs) catalyze adenosine to inosine RNA editing. However, the functional role of ADAR2 in NAFLD is unclear. ADAR2+/+/GluR-BR/R mice (wild type, WT) and ADAR2-/-/GluR-BR/R mice (ADAR2 KO) mice are fed with standard chow or high-fat diet (HFD) for 12 weeks. ADAR2 KO mice exhibit protection against HFD-induced glucose intolerance, insulin resistance, and dyslipidemia. Moreover, ADAR2 KO mice display reduced liver lipid droplets in concert with decreased hepatic TG content, improved hepatic insulin signaling, better pyruvate tolerance, and increased glycogen synthesis. Mechanistically, ADAR2 KO effectively mitigates excessive lipid production via AMPK/Sirt1 pathway. ADAR2 KO inhibits hepatic gluconeogenesis via the AMPK/CREB pathway and promotes glycogen synthesis by activating the AMPK/GSK3β pathway. These results provide evidence that ADAR2 KO protects against NAFLD progression through the activation of AMPK signaling pathways.

Genetics of murine type 2 diabetes and comorbidities

ABSTRAC

Type 2 diabetes (T2D) is a polygenic and multifactorial complex disease, defined as chronic metabolic disorder. It's a major global health concern with an estimated 463 million adults aged 20-79 years with diabetes and projected to increase up to 700 million by 2045. T2D was reported to be one of the four leading causes of non-communicable disease (NCD) deaths in 2012. Environmental factors play a part in the development of polygenic forms of diabetes. Polygenic forms of diabetes often run-in families. Fortunately, T2D, which accounts for 90-95% of the entire four types of diabetes including, Type 1 diabetes (T1D), T2D, monogenic diabetes syndromes (MGDS), and Gestational diabetes mellitus, can be prevented or delayed through nutrition and lifestyle changes as well as through pharmacologic interventions. Typical symptom of the T2D is high blood glucose levels and comprehensive insulin resistance of the body, producing an impaired glucose tolerance. Impaired glucose tolerance of T2D is accompanied by extensive health complications, including cardiovascular diseases (CVD) that vary in morbidity and mortality among populations. The pathogenesis of T2D varies between populations and/or ethnic groupings and is known to be attributed extremely by genetic components and environmental factors. It is evident that genetic background plays a critical role in determining the host response toward certain environmental conditions, whether or not of developing T2D (susceptibility versus resistant). T2D is considered as a silent disease that can progress for years before its diagnosis. Once T2D is diagnosed, many metabolic malfunctions are observed whether as side effects or as independent comorbidity. Mouse models have been proven to be a powerful tool for mapping genetic factors that underline the susceptibility to T2D development as well its comorbidities. Here, we have conducted a comprehensive search throughout the published data covering the time span from early 1990s till the time of writing this review, for already reported quantitative trait locus (QTL) associated with murine T2D and comorbidities in different mouse models, which contain different genetic backgrounds. Our search has resulted in finding 54 QTLs associated with T2D in addition to 72 QTLs associated with comorbidities associated with the disease. We summarized the genomic locations of these mapped QTLs in graphical formats, so as to show the overlapping positions between of these mapped QTLs, which may suggest that some of these QTLs could be underlined by sharing gene/s. Finally, we reviewed and addressed published reports that show the success of translation of the identified mouse QTLs/genes associated with the disease in humans.

Positive association between nonalcoholic fatty liver disease and growth hormone deficiency in patients with nonfunctioning pituitary adenoma

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) is characterized by growth hormone deficiency (GHd). We investigated the association between NAFLD and GHd in patients with nonfunctioning pituitary adenomas (NFPA).

DESIGN AND METHODS

We recruited patients with NFPA who underwent transsphenoidal adenectomy between January 2005 and December 2018. Pituitary function was determined by the insulin tolerance test, thyroid hormone assay, and gonadal hormone levels. NAFLD was defined as a hepatic steatosis index greater than 36.

RESULTS

Among 278 patients (mean age, 44.2 years; 58.6% [n=163] female), 103 (37.0%) had GHd, 139 (50.0%) had hypogonadism, and 75 (27.0%) had NAFLD. The prevalence of NAFLD was significantly higher in patients with GHd than in those without (36.9% vs. 21.1%, p=0.01). Even after adjusting for age, total cholesterol level, gonadal function, and prolactin level, patients with GHd had approximately two-fold higher prevalence of NALFD than those without GHd (adjusted odds ratio [OR]=1.85, 95% confidence interval [CI]=1.05-3.28, p=0.03). Among female patients, the prevalence of NALFD was significantly higher in those with GHd than in those without (adjusted OR=2.39, 95% CI=1.03-5.55, p=0.04); whereas, among male patients, the prevalence of NAFLD was statistically similar between those with and without GHd (p>0.05). In addition, gonadal function did not affect the prevalence of NAFLD in patients with NFPA (29.3% with eugonadism vs. 47.8% with hypogonadism, p=0.14).

CONCLUSION

Among patients with NFPA, the prevalence of NAFLD was two-fold higher in patients with GHd than that in those without GHd. Thus, screening for NAFLD might be required in NFPA patients with GHd.

Evidence-based clinical advice for nutrition and dietary weight loss strategies for the management of NAFLD and NASH

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide and affects approximately one third of adults in the United States. The disease is becoming a global epidemic as a result of the rising rates of obesity and metabolic disease. Emerging data suggest weight loss of ≥10% overall body weight is beneficial in resolving steatosis and reversing fibrosis. Prospective trials comparing various diets are limited by lack of sufficient power as well as pre- and post-treatment histopathology, and therefore no specific diet is recommended at this time. In this narrative review we examine the pathophysiology behind specific macronutrient components that can either promote or reverse NAFLD to help inform more specific dietary recommendations. Overall, the data supports reducing saturated fat, refined carbohydrates, and red and processed meats in the diet, and increasing the consumption of plant-based foods. Diets that incorporate these recommendations include plant-based diets such as the Dietary Approaches to Stop Hypertension, Mediterranean, vegetarian, and vegan diets.

Body Fat Changes and Liver Safety in Obese and Overweight Women Supplemented with Conjugated Linoleic Acid: A 12-Week Randomised, Double-Blind, Placebo-Controlled Trial

Preliminary evidence suggests that conjugated linoleic acid (CLA) may reduce body weight and affect body composition. The present study assessed the effect of CLA supplementation on body fat composition in overweight and obese women, while also evaluating the liver safety of CLA use. Seventy-four obese or overweight women were randomly assigned to receive 3 g/day CLA or placebo for 12 weeks. Body composition (dual-energy X-ray absorptiometry) and liver function (¹³C-methacetin breath test and serum liver enzymes) were assessed before and after the trial. Patients receiving CLA experienced a significant reduction of total body fat expressed as mass (p = 0.0007) and percentage (p = 0.0006), android adipose tissue (p = 0.0002), gynoid adipose tissue (p = 0.0028), and visceral adipose tissue (p = 4.2 × 10⁻⁹) as well as a significant increase in lean body mass to height (p = 6.1 × 10⁻¹¹) when compared to those receiving a placebo. The maximum momentary 13C recovery changes and end-point values were significantly higher in the CLA group when compared to the placebo group (p = 0.0385 and p = 0.0076, respectively). There were no significant changes in alanine aminotransferase, asparagine aminotransferase, and gamma-glutamyl transpeptidase activities between the groups. In conclusion, CLA supplementation was well tolerated and safe for the liver, which shows beneficial effects on fat composition in overweight and obese women.

miRNA Dysregulation in the Development of Non-Alcoholic Fatty Liver Disease and the Related Disorders Type 2 Diabetes Mellitus and Cardiovascular Disease

According to the World Health Organization, the continuing surge in obesity pandemic creates a substantial increase in incidences of metabolic disorders, such as non-alcoholic fatty liver disease (NAFLD), type 2 diabetes mellitus, and cardiovascular disease. MicroRNAs (miRNAs) belong to an evolutionarily conserved class of short (20-22 nucleotides in length) and single-stranded non-coding RNAs. In mammals, miRNAs function as critical post-transcriptional negative regulators involved not only in many biological processes but also in the development of many diseases such as NAFLD and comorbidities. More recently, it has been described that cells can secrete miRNAs in extracellular vesicles, transported by body fluids, and uptaken by other tissues regulating gene expression. Therefore, this could be a mechanism of signaling involved not only in physiological pathways but also in the development of diseases. The association of some miRNA expression profiles with certain disorders has made them very interesting molecules for diagnosis, prognosis, and disease management. The finding of specific miRNA signatures to diagnose NAFLD and related diseases could anticipate the risk of development of related complications and, actually, it is the driving force of present health strategies worldwide. In this review, we have included latest advances in knowledge about the miRNAs involved in the development of NAFLD and related diseases and examined how this knowledge could be used to identify new non-invasive biomarkers and new pharmacological interventions.

Range of Normal Serum Aminotransferase Levels in Liver Transplant Recipients

Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are used to monitor liver transplant recipients (LTR) but the reference range and context of its use is not well defined. We aimed to determine the healthy ranges in LTR without chronic liver disease.

METHODS

One hundred and three LTR without chronic liver disease based on serology, transient elastography with controlled attenuated parameter, and ultrasound were included. A healthy range of aminotransferases was set to 95th percentile. An updated normal aminotransferase range was used to detect recurrence in post-liver transplantation (LT) with hepatitis C virus (HCV) and nonalcoholic fatty liver disease (NAFLD).

RESULTS

The normal ALT and AST range was 0 to 57 and 0 to 54 IU/L, respectively, in LTR and was not affected by age, sex, obesity, or choice of immunosuppressant. The diagnostic performance of serum ALT and AST to detect recurrence of NAFLD by a controlled attenuated parameter was poor with area under the receiver operating characteristic curve of 0.573 (95% confidence interval 0.493, 0.655; P = .08) and 0.537 (0.456, 0.618; P = .4), respectively. In contrast, the diagnostic performance of ALT and AST to detect recurrence of HCV after LT was 0.906 (0.868, 0.944; P < .001) and 0.925 (0.890, 0.959; P < .001), respectively.

CONCLUSION

The updated aminotransferase range in LTR is higher than the general population and accurate for detecting recurrent HCV, but not NAFLD.

Non-HDL-cholesterol to HDL-cholesterol ratio is a better predictor of new-onset non-alcoholic fatty liver disease than non-HDL-cholesterol: a cohort study

Background

The nonHDLc/HDLc ratio (in which nonHDLc is defined as total cholesterol minus HDLc) is positively associated with multiple dyslipidemia-related disorders. This study aimed to determine whether the nonHDLc/HDLc ratio is an independent predictor of new-onset NAFLD (non-alcoholic fatty liver disease) in Chinese population.

Methods

A perspective cohort study consisting of 3374 Chinese adults without liver diseases or metabolic disturbances was performed. Anthropometric parameters and data of metabolic and plasma lipid profile were collected. Univariate and multivariate Cox proportional analyses were carried out to evaluate the association of the nonHDLc/HDLc ratio with incident NAFLD. ROC curve analysis was preformed to compare the predictive value between the nonHDLc/HDLc and the nonHDLc for NAFLD.

Results

Two thousand seven hundred seventeen participants were included in the final analysis. During a median follow-up period of 1.6 years, 264 participants (9.71%) developed NAFLD. After adjustment for potential confounders, a high nonHDLc/HDLc ratio (highest tertile) was associated with elevated risk of NAFLD (HR = 2.66; 95% CI, 1.13–6.24; P = 0.025 in female and HR = 2.11; 95% CI, 1.15–3.90; P = 0.016 in male). A nonlinear relationship was observed when the nonHDLc/HDLc ratio was ≤3.5. AUC values for nonHDLc/HDLc ratios (0.717 in female and 0.682 in male) were significantly higher than nonHDLc (0.675 in female and 0.653 in male) (P = 0.049 in female and P = 0.037 in male). In addition, the optimal cut-off value of nonHDLc/HDLc ratio for detection of NAFLD was 2.4 in female and 2.3 in male.

Conclusions

The nonHDLc/HDLc ratio is an independent predictor of NAFLD and a stronger predictor than nonHDLc in Chinese population, which might be expected to better guide early identification of individuals at risk of NAFLD.

Non-Alcoholic Fatty Liver Disease in Africa and Middle East: An Attempt to Predict the Present and Future Implications on the Healthcare System

Non-alcoholic fatty liver disease (NAFLD) encompasses a group of hepatic diseases that range in severity. NAFLD is increasingly recognized as an epidemic among different populations, including those in Africa and the Middle East. The objective of this narrative review is to document the prevalence of and risk factors for NAFLD in Africa and the Middle East and the potential implications on the healthcare systems. An in-depth search on Google Scholar, Medline and PubMed was conducted using the terms "non-alcoholic fatty liver disease" and "non-alcoholic steatohepatitis", in addition to "prevalence and risk factors for NAFLD", with special emphasis on Africa and the Middle East countries. There were three types of epidemiological studies that included prevalence, risk factors and management/complications of NAFLD. There was noticeable variation in the prevalence of NAFLD among different countries, based on the variation in the prevalence of risk factors (type 2 diabetes, obesity, metabolic syndrome and dyslipidemia) and the diagnostic tool used in the study. However, the highest prevalence rate was reported in some Middle East countries. In Africa, there were few studies about NAFLD and most reported variable prevalence rates. There is an increasing prevalence of NAFLD as a result of the increasing risk factors, particularly in the Middle East, while in Africa, the situation is still unclear. Health providers in these regions are faced with many challenges that need urgent plans.

Hepatic FGF21 mediates sex differences in high-fat high-fructose diet-induced fatty liver

The role of gender in the progression of fatty liver due to chronic high-fat high-fructose diet (HFFD) has not been studied. The present investigation assessed whether HFFD induced hepatic perturbations differently between the sexes and examined the potential mechanisms. Male, female, and ovariectomized (OVX) Sprague-Dawley rats were fed either a control diet or HFFD for 12 wk. Indexes of liver damage and hepatic steatosis were analyzed biochemically and histologically together with monitoring changes in hepatic gene and protein expression. HFFD induced a higher degree of hepatic steatosis in females, with significant increases in proteins involved in hepatic lipogenesis, whereas HFFD significantly induced liver injury, inflammation, and oxidative stress only in males. Interestingly, a significant increase in hepatic fibroblast growth factor 21 (FGF21) protein expression was observed in HFFD-fed males but not in HFFD-fed females. Ovarian hormone deprivation by itself led to a significant reduction in FGF21 with hepatic steatosis, and HFFD further aggravated hepatic fat accumulation in OVX rats. Importantly, estrogen replacement restored hepatic FGF21 levels and reduced hepatic steatosis in HFFD-fed OVX rats. Collectively, our results indicate that male rats are more susceptible to HFFD-induced hepatic inflammation and that the mechanism underlying this sex dimorphism is mediated through hepatic FGF21 expression. Our findings reveal sex differences in the development of HFFD-induced fatty liver and indicate the protective role of estrogen against HFFD-induced hepatic steatosis.

Cost-effectiveness analysis of ultrasonography screening for nonalcoholic fatty liver disease in metabolic syndrome patients

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) can be diagnosed early by noninvasive ultrasonography; however, the cost-effectiveness of ultrasonography screening with intensive weight reduction program in metabolic syndrome patients is not clear. This study aims to estimate economic and clinical outcomes of ultrasonography in Thailand.

METHODS

Cost-effectiveness analysis used decision tree and Markov models to estimate lifetime costs and health benefits from societal perspective, based on a cohort of 509 metabolic syndrome patients in Thailand. Data were obtained from published literatures and Thai database. Results were reported as incremental cost-effectiveness ratios (ICERs) in 2014 US dollars (USD) per quality-adjusted life year (QALY) gained with discount rate of 3%. Sensitivity analyses were performed to assess the influence of parameter uncertainty on the results.

RESULTS

The ICER of ultrasonography screening of 50-year-old metabolic syndrome patients with intensive weight reduction program was 958 USD/QALY gained when compared with no screening. The probability of being cost-effective was 67% using willingness-to-pay threshold in Thailand (4848 USD/QALY gained). Screening before 45 years was cost saving while screening at 45 to 64 years was cost-effective.

CONCLUSIONS

For patients with metabolic syndromes, ultrasonography screening for NAFLD with intensive weight reduction program is a cost-effective program in Thailand. Study can be used as part of evidence-informed decision making.

TRANSLATIONAL IMPACTS

Findings could contribute to changes of NAFLD diagnosis practice in settings where economic evidence is used as part of decision-making process. Furthermore, study design, model structure, and input parameters could also be used for future research addressing similar questions.

Alcohol, microbiome, life style influence alcohol and non-alcoholic organ damage

This paper is based upon the "8th Charles Lieber's Satellite Symposium" organized by Manuela G. Neuman at the Research Society on Alcoholism Annual Meeting, on June 25, 2016 at New Orleans, Louisiana, USA. The integrative symposium investigated different aspects of alcohol-induced liver disease (ALD) as well as non-alcohol-induced liver disease (NAFLD) and possible repair. We revealed the basic aspects of alcohol metabolism that may be responsible for the development of liver disease as well as the factors that determine the amount, frequency and which type of alcohol misuse leads to liver and gastrointestinal diseases. We aimed to (1) describe the immuno-pathology of ALD, (2) examine the role of genetics in the development of alcoholic hepatitis (ASH) and NAFLD, (3) propose diagnostic markers of ASH and non-alcoholic steatohepatitis (NASH), (4) examine age and ethnic differences as well as analyze the validity of some models, (5) develop common research tools and biomarkers to study alcohol-induced effects, 6) examine the role of alcohol in oral health and colon and gastrointestinal cancer and (7) focus on factors that aggravate the severity of organ-damage. The present review includes pre-clinical, translational and clinical research that characterizes ALD and NAFLD. Strong clinical and experimental evidence lead to recognition of the key toxic role of alcohol in the pathogenesis of ALD with simple fatty infiltrations and chronic alcoholic hepatitis with hepatic fibrosis or cirrhosis. These latter stages may also be associated with a number of cellular and histological changes, including the presence of Mallory's hyaline, megamitochondria, or perivenular and perisinusoidal fibrosis. Genetic polymorphisms of ethanol metabolizing enzymes and cytochrome p450 (CYP) 2E1 activation may change the severity of ASH and NASH. Other risk factors such as its co-morbidities with chronic viral hepatitis in the presence or absence of human deficiency virus were discussed. Dysregulation of metabolism, as a result of ethanol exposure, in the intestine leads to colon carcinogenesis. The hepatotoxic effects of ethanol undermine the contribution of malnutrition to the liver injury. Dietary interventions such as micro and macronutrients, as well as changes to the microbiota have been suggested. The clinical aspects of NASH, as part of the metabolic syndrome in the aging population, have been presented. The symposium addressed mechanisms and biomarkers of alcohol induced damage to different organs, as well as the role of the microbiome in this dialog. The microbiota regulates and acts as a key element in harmonizing immune responses at intestinal mucosal surfaces. It is known that microbiota is an inducer of proinflammatory T helper 17 cells and regulatory T cells in the intestine. The signals at the sites of inflammation mediate recruitment and differentiation in order to remove inflammatory inducers and promote tissue homeostasis restoration. The change in the intestinal microbiota also influences the change in obesity and regresses the liver steatosis. Evidence on the positive role of moderate alcohol consumption on heart and metabolic diseases as well on reducing steatosis have been looked up. Moreover nutrition as a therapeutic intervention in alcoholic liver disease has been discussed. In addition to the original data, we searched the literature (2008-2016) for the latest publication on the described subjects. In order to obtain the updated data we used the usual engines (Pub Med and Google Scholar). The intention of the eighth symposia was to advance the international profile of the biological research on alcoholism. We also wish to further our mission of leading the forum to progress the science and practice of translational research in alcoholism.

Adaptation of liver stiffness measurement depth in bariatric surgery candidates with suspected nonalcoholic fatty liver disease

BACKGROUND AND AIMS

A thick layer of subcutaneous adipose tissue may lead to an overestimation of liver stiffness by transient elastography. The aim of this study was to assess whether liver stiffness measurement (LSM) was overestimated using an XL probe in patients with severe obesity and, if so, to reprocess the data to the adapted depth to obtain the appropriate LSM (LSMa).

METHODS

A total of 152 obese patients prospectively underwent bariatric surgery and needle liver biopsy. Liver stiffness was measured by transient elastography 15 days before. To determine whether the LSM was overestimated, an expert operator retrospectively determined whether the skin-to-capsula distance was greater than 35 mm by analyzing the hyperechogenicity of ultrasound signals and the measured slope between 35 and 75 mm. In the case of an overestimation, a deeper measurement depth was selected to calculate the LSMa.

RESULTS

There was an overestimation of the LSM obtained between 35 and 75 mm in 76 patients (50%). Among these patients, the LSMa was obtained between 40 and 75 mm in 49 patients and between 45 and 80 mm in 27 patients. Only the percentage of steatosis was independently and positively correlated with LSM overestimation. The areas under receiver operating characteristic of LSMa was 0.82±0.04 for predicting fibrosis stage F3. The Obuchowski measure was 0.85±0.02.

CONCLUSION

The LSM was overestimated in severely obese patients obtained between 35 and 75 mm using an XL probe in 76 patients (50%), but LSM can be performed correctly in these patients after adapting the measurement depth to deeper beneath the patients' skin.

Role of intrahepatic B cells in non-alcoholic fatty liver disease by secreting pro-inflammatory cytokines and regulating intrahepatic T cells

OBJECTIVE

To investigate the alterations and functions of intrahepatic B (IHB) cells in non-alcoholic fatty liver disease (NAFLD) model induced by high-fat diet (HFD).

METHODS

C57BL/6 J mice were fed with HFD for 16 weeks to induce NAFLD. Flow cytometry was used to analyze lymphocytes from liver, spleen and peripheral blood mononuclear cells (PBMC). Real-time polymerase chain reaction and immunofluorescence stain were applied to investigate cytokine expression in the intrahepatic lymphocytes and IHB cells. CD4(+) intrahepatic T (IHT) cells and IHB cells were enriched by a magnetic-activated cell sorting method and cultured in vitro. The cytokines and immunoglobulin (Ig) levels in the plasma, cultural supernatants and liver homogenates were monitored with cytometric bead arrays or multiplex immunoassays.

RESULTS

The percentage of IHB cells in CD45(+) cells was significantly higher in the NAFLD group than in the control group (P < 0.05). IHB cells expressed higher levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in the NAFLD group, and produced higher levels of IL-6 and TNF-α under the stimulation of lipopolysaccharide (LPS) than the control group. IgG2a levels were higher in the plasma, liver homogenates and the culture supernatants of IHB cells after stimulated by LPS and anti-CD40/IgM in the NAFLD group than in the control group. Moreover, IHB cells enhanced the activation of CD4(+) IHT cells and promoted the differentiation into T helper (Th) 1 cells in the NAFLD group.

CONCLUSION

IHB cells might be involved in NAFLD both by inducing the secretion of IL-6, TNF-α and IgG2a and by enhancing the activation of CD4(+) IHT cells and their differentiation into Th1 cells.

Deepure Tea Improves High Fat Diet-Induced Insulin Resistance and Nonalcoholic Fatty Liver Disease

This study was to explore the protective effects of Deepure tea against insulin resistance and hepatic steatosis and elucidate the potential underlying molecular mechanisms. C57BL/6 mice were fed with a high fat diet (HFD) for 8 weeks to induce the metabolic syndrome. In the Deepure tea group, HFD mice were administrated with Deepure tea at 160 mg/kg/day by gavage for 14 days. The mice in HFD group received water in the same way over the same period. The age-matched C57BL/6 mice fed with standard chow were used as normal control. Compared to the mice in HFD group, mice that received Deepure tea showed significantly reduced plasma insulin and improved insulin sensitivity. Deepure tea increased the expression of insulin receptor substrate 2 (IRS-2), which plays an important role in hepatic insulin signaling pathway. Deepure tea also led to a decrease in hepatic fatty acid synthesis and lipid accumulation, which were mediated by the downregulation of sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthesis (FAS), and acetyl-CoA carboxylase (ACC) proteins that are involved in liver lipogenesis. These results suggest that Deepure tea may be effective for protecting against insulin resistance and hepatic steatosis via modulating IRS-2 and downstream signaling SREBP-1c, FAS, and ACC.

Liver-specific GH receptor gene-disrupted (LiGHRKO) mice have decreased endocrine IGF-I, increased local IGF-I, and altered body size, body composition, and adipokine profiles

GH is an important regulator of body growth and composition as well as numerous other metabolic processes. In particular, liver plays a key role in the GH/IGF-I axis, because the majority of circulating "endocrine" IGF-I results from GH-stimulated liver IGF-I production. To develop a better understanding of the role of liver in the overall function of GH, we generated a strain of mice with liver-specific GH receptor (GHR) gene knockout (LiGHRKO mice). LiGHRKO mice had a 90% decrease in circulating IGF-I levels, a 300% increase in circulating GH, and significant changes in IGF binding protein (IGFBP)-1, IGFBP-2, IGFBP-3, IGFBP-5, and IGFBP-7. LiGHRKO mice were smaller than controls, with body length and body weight being significantly decreased in both sexes. Analysis of body composition over time revealed a pattern similar to those found in GH transgenic mice; that is, LiGHRKO mice had a higher percentage of body fat at early ages followed by lower percentage of body fat in adulthood. Local IGF-I mRNA levels were significantly increased in skeletal muscle and select adipose tissue depots. Grip strength was increased in LiGHRKO mice. Finally, circulating levels of leptin, resistin, and adiponectin were increased in LiGHRKO mice. In conclusion, LiGHRKO mice are smaller despite increased local mRNA expression of IGF-I in several tissues, suggesting that liver-derived IGF-I is indeed important for normal body growth. Furthermore, our data suggest that novel GH-dependent cross talk between liver and adipose is important for regulation of adipokines in vivo.

Association of adipose tissue and liver fibrosis with tissue stiffness in morbid obesity: links with diabetes and BMI loss after gastric bypass

CONTEXT

Liver and white adipose tissue (WAT) develop inflammation and fibrosis.

OBJECTIVE

The aim of the study was to evaluate the bioclinical relevance of WAT fibrosis in morbid obesity and diabetes and the relationships with tissue stiffness measured using a novel device.

DESIGN AND SETTING

Observational and longitudinal studies were conducted in a hospital nutrition department.

PATIENTS

Biopsies of liver and subcutaneous WAT (scWAT) and omental adipose tissue were collected from 404 obese bariatric surgery candidates, of whom 243 were clinically characterized before surgery and 3, 6, and 12 months after surgery. In 123 subjects, liver and scWAT stiffness was assessed noninvasively using vibration-controlled transient elastography (VCTE).

INTERVENTIONS

Bariatric surgery was performed for some patients.

MAIN OUTCOME MEASURE

Adipose tissue fibrosis and stiffness and their link to obesity phenotypes were measured.

RESULTS

scWAT fibrosis was positively associated with liver fibrosis (fibrosis score ≥2) (ϱ= 0.14; P = .01). VCTE-evaluated liver and scWAT stiffness was positively correlated with immunohistochemistry-determined liver (ϱ= 0.46; P = .0009) and scWAT fibrosis (ϱ= 0.48; P = .0001). VCTE-evaluated scWAT stiffness measures negatively associated with dual-energy x-ray absorptiometry-evaluated body fat mass (R = -0.25; P = .009) and were correlated with metabolic variables. Diabetic subjects showed increased scWAT stiffness. Participants less responsive to gastric bypass were older and more frequently diabetic, and they had increased body mass index, serum IL-6, and scWAT and liver fibrosis. Subjects with no diabetes and normal liver had higher fat mass and lower tissue fibrosis and stiffness.

CONCLUSION

scWAT stiffness was associated with tissue fibrosis, obesity, and diabetes-related traits. Noninvasive evaluation of scWAT stiffness might be useful in clinical practice.

Effect of high-fat diet prior to pregnancy on hepatic gene expression and histology in mouse offspring

Maternal overnutrition and obesity are associated with fetal development and cause long-term effects in offspring. However, the effects of a high-fat diet specific to the pre-pregnancy period are not determined. The present study aimed to examine the effect of high-fat diet prior to pregnancy on the liver of mouse offspring. Female C57BL/6J mice were fed a normal chow (15.2% fat by energy) [control diet (CTR) and CTR pre-pregnancy (PP) groups] or a high-fat chow (31.2% fat by energy) [high-fat diet (HFD) and HFD-pre-pregnancy (PP) groups] for 3-4 weeks and then mated with male C57BL/6J mice fed normal chow. Some mothers continued on the same diet until pups reached 21 days of age (CTR and HFD), and others were fed the different chows from gestational day 0 (CTR-PP and HFD-PP) to determine the effects of a high-fat diet during the pre-pregnancy period in HFD-PP/CTR and HFD/CTR-PP comparisons. Liver tissues from pups were subjected to gene expression analysis by quantitative reverse transcription-polymerase chain reaction (RT-PCR) and microarray, and histological analysis using Oil Red O staining (Sigma Chemical Co., Ltd., Balcatta, WA, USA). Lipid droplets were increased in hepatocytes of mice in HFD-PP compared to CTR and those in HFD compared to CTR-PP. Expression of stearoyl-coenzyme A desaturase 1 (Scd1), acetyl-coenzyme A carboxylase beta (Acacb), and fatty acid binding protein 5 (Fabp5) was increased by maternal high-fat diet during pre-pregnancy. The results showed that maternal high-fat diet intake prior to pregnancy uniquely affects metabolic phenotype related to health and disease in the liver of the next generation.

Herbal medicines for fatty liver diseases

BACKGROUND

Fatty liver disease is potentially a reversible condition that may lead to end-stage liver disease. Since herbal medicines such as Crataegus pinnatifida and Salvia miltiorrhiza have increasingly been used in the management of fatty liver disease, a systematic review on herbal medicine for fatty liver disease is needed.

OBJECTIVES

To assess the beneficial and harmful effects of herbal medicines for people with alcoholic or non-alcoholic fatty liver disease.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 3, 2012), MEDLINE, EMBASE, and Science Citation Index Expanded to 1 March 2012. We also searched the Chinese BioMedical Database, Traditional Chinese Medical Literature Analysis and Retrieval System, China National Knowledge Infrastructure, Chinese VIP Information, Chinese Academic Conference Papers Database and Chinese Dissertation Database, and the Allied and Complementary Medicine Database to 2 March 2012.

SELECTION CRITERIA

We included randomised clinical trials comparing herbal medicines with placebo, no treatment, a pharmacological intervention, or a non-pharmacological intervention such as diet or lifestyle, or Western interventions in participants with fatty liver disease.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data independently. We used the 'risk of bias' tool to assess the risk of bias of the included trials. We assessed the following domains: random sequence generation, allocation concealment, blinding, incomplete outcome data, selective outcome reporting, and other sources of bias. We presented the effects estimates as risk ratios (RR) with 95% confidence intervals (CI) or as mean differences (MD) with 95% CI, depending on the variables of the outcome measures.

MAIN RESULTS

We included 77 randomised clinical trials, which included 6753 participants with fatty liver disease. The risks of bias (overestimation of benefits and underestimation of harms) was high in all trials. The mean sample size was 88 participants (ranging from 40 to 200 participants) per trial. Seventy-five different herbal medicine products were tested. Herbal medicines tested in the randomised trials included single-herb products (Gynostemma pentaphyllum, Panax notoginseng, and Prunus armeniaca), proprietary herbal medicines commercially available, and combination formulas prescribed by practitioners. The most commonly used herbs were Crataegus pinnatifida,Salvia miltiorrhiza,Alisma orientalis,Bupleurum Chinense,Cassia obtusifolia, Astragalus membranaceous, and Rheum palmatum. None of the trials reported death, hepatic-related morbidity, quality of life, or costs. A large number of trials reported positive effects on putative surrogate outcomes such as serum aspartate aminotransferase, alanine aminotransferase, glutamyltransferase, alkaline phosphatases, ultrasound, and computed tomography scan. Twenty-seven trials reported adverse effects and found no significant difference between herbal medicines versus control. However, the risk of bias of the included trials was high.The outcomes were ultrasound findings in 22 trials, liver computed tomography findings in eight trials, aspartate aminotransferase levels in 64 trials, alanine aminotransferase activity in 77 trials, and glutamyltransferase activities in 44 trials. Six herbal medicines showed statistically significant beneficial effects on ultrasound, four on liver computed tomography, 42 on aspartate aminotransferase activity, 49 on alanine aminotransferase activity, three on alkaline phosphatases activity, and 32 on glutamyltransferase activity compared with control interventions.

AUTHORS' CONCLUSIONS

Some herbal medicines seemed to have positive effects on aspartate aminotransferase, alanine aminotransferase, ultrasound, and computed tomography. We found no significant difference on adverse effects between herbal medicine and control groups. The findings are not conclusive due to the high risk of bias of the included trials and the limited number of trials testing individual herbal medicines. Accordingly, there is also high risk of random errors.

Nonalcoholic fatty liver disease: an emerging threat to obese and diabetic individuals

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in the Western world and its incidence is increasing rapidly. NAFLD is a spectrum ranging from simple steatosis, which is relatively benign hepatically, to nonalcoholic steatohepatitis (NASH), which can progress to cirrhosis. Obesity, insulin resistance, type 2 diabetes mellitus, and dyslipidemia are the most important risk factors for NAFLD. Due to heavy enrichment with metabolic risk factors, individuals with NAFLD are at significantly higher risk for cardiovascular disease. Individuals with NAFLD have higher incidence of type 2 diabetes. The diagnosis of NAFLD requires imaging evidence of hepatic steatosis in the absence of competing etiologies including significant alcohol consumption. Liver biopsy remains the gold standard for diagnosing NASH and for determining prognosis. Weight loss remains a cornerstone of treatment. Weight loss of ∼5% is believed to improve steatosis, whereas ∼10% weight loss is necessary to improve steatohepatitis. A number of pharmacologic therapies have been investigated to treat NASH, and agents such as vitamin E and thiazolidinediones have shown promise in select patient subgroups.

Female mice are more susceptible to nonalcoholic fatty liver disease: sex-specific regulation of the hepatic AMP-activated protein kinase-plasminogen activator inhibitor 1 cascade, but not the hepatic endotoxin response

As significant differences between sexes were found in the susceptibility to alcoholic liver disease in human and animal models, it was the aim of the present study to investigate whether female mice also are more susceptible to the development of non-alcoholic fatty liver disease (NAFLD). Male and female C57BL/6J mice were fed either water or 30% fructose solution ad libitum for 16 wks. Liver damage was evaluated by histological scoring. Portal endotoxin levels and markers of Kupffer cell activation and insulin resistance, plasminogen activator inhibitor 1 (PAI-1) and phosphorylated adenosine monophosphate-activated protein kinase (pAMPK ) were measured in the liver. Adiponectin mRNA expression was determined in adipose tissue. Hepatic steatosis was almost similar between male and female mice; however, inflammation was markedly more pronounced in livers of female mice. Portal endotoxin levels, hepatic levels of myeloid differentiation primary response gene (88) (MyD88) protein and of 4-hydroxynonenal protein adducts were elevated in animals with NAFLD regardless of sex. Expression of insulin receptor substrate 1 and 2 was decreased to a similar extent in livers of male and female mice with NAFLD. The less pronounced susceptibility to liver damage in male mice was associated with a superinduction of hepatic pAMPK in these mice whereas, in livers of female mice with NAFLD, PAI-1 was markedly induced. Expression of adiponectin in visceral fat was significantly lower in female mice with NAFLD but unchanged in male mice compared with respective controls. In conclusion, our data suggest that the sex-specific differences in the susceptibility to NAFLD are associated with differences in the regulation of the adiponectin-AMPK-PAI-1 signaling cascade.