Nonalcoholic fatty liver disease: current and potential therapies

Impact of obesity on liver function tests: is nonalcoholic fatty liver disease the only player? A review article

Objectives

Obesity and nonalcoholic fatty liver disease (NAFLD) are common worldwide health problems with a strong relationship in between. NAFLD is currently the most common cause of abnormal liver function tests (LFT) because of obesity pandemic. The question is NAFLD the only player of abnormal LFT in obesity?

Methodology

This article reviews the most important topics regarding the derangements of LFT in obesity through a PubMed search strategy for all English-language literature.

Results

The reported abnormal LFT in obesity were increased serum levels of transaminases (alanine aminotransaminase, aspartate aminotransaminase), gamma glutamyl transferase, and alkaline phosphatase and decreased serum levels of bilirubin and albumin. Besides novel potential hepatic markers of NAFLD/NASH such as triglycerides/high-density lipoprotein cholesterol ratio, sex hormone-binding globulin, fibroblast growth factor 21, and markers of hepatocyte apoptosis i.e. cytokeratin 18 and microribonucleic acids (miRNAs). Beyond NAFLD, there are other underlying players for the abnormal LFT in obesity such as oxidative stress, inflammation, and insulin resistance.

Conclusion

Derangements of LFT in obesity are attributed to NAFLD but also to obesity itself and its related oxidative stress, insulin resistance, and chronic inflammatory state. Abnormal LFT predict more than just liver disease.

Extraction, purification, structural characterization, and hepatoprotective effect of the polysaccharide from purple sweet potato

BACKGROUND

Purple sweet potato Ipomoea batatas (L.) has long been used as a medicine and a food. It contains various bioactive substances such as polysaccharides, anthocyanins, and flavonoids. Purple sweet potato polysaccharides are known to have anti-oxidant, anti-tumor, and immunomodulatory functions. Nevertheless, studies on the structural characterization of purple sweet potato polysaccharides and their ability to prevent non-alcoholic fatty liver disease (NAFLD) have rarely been reported.

RESULTS

A novel polysaccharide (PSPP-A) was extracted and isolated from purple sweet potato, and its structural characteristics and preventive effects on NAFLD were investigated. The results indicated that PSPP-A was composed of l-rhamnose, d-arabinose, d-galactose, d-glucose, and d-glucuronic acid with molar ratios of 1.89:8.45:1.95:1.13:1. Its molecular weight was 2.63 × 10³  kDa. Methylation and nuclear magnetic resonance (NMR) analysis indicated that the glycosidic linkages were →3)-α-L-Araf-(1→, α-L-Araf-(1→, →2,4)-α-L-Rhap-(1→, 4-O-Me-β-D-GlcAp-(1→, →4)-α-D-Glcp-(1→, →4)-β-D-Galp-(1→, and →6)-β-D-Galp-(1→. Scanning electron microscopy (SEM) indicated that the structure of PSPP-A was irregular. Subsequently, the protective effect of PSPP-A on NAFLD was investigated. The results indicated that bodyweight, liver index, and triglyceride (TG), total cholesterol (TC), aspartate transaminase (AST), and alanine transaminase (ALT) content were significantly reduced by intervention of purple sweet potato polysaccharide-A (PSPP-A) compared with the - high-fat diet group. Liver histopathological analysis indicated that PSPP-A attenuated irregular hepatocyte patterns and excessive lipid vacuoles.

CONCLUSIONS

The novel polysaccharide, PSPP-A, mainly contains arabinose, which has certain preventive effects on NAFLD. This study provides a theoretical basis for further elucidating the hepatoprotective effect of purple sweet potatoes as a functional food. © 2022 Society of Chemical Industry.

Efficacy and mechanism of Jiedu Tongluo Tiaogan Formula in treating type 2 diabetes mellitus combined with non-alcoholic fatty liver disease: Study protocol for a parallel-armed, randomized controlled trial

Background: The incidence of Type 2 diabetes mellitus (T2DM) combined with non-alcoholic fatty liver disease (NAFLD) has risen over the years. This comorbid condition significantly increases the probability of cirrhosis, liver cancer, and mortality compared to the disease alone. The multi-targeted, holistic treatment efficacy of traditional Chinese medicine (TCM) plays a vital role in the treatment of T2DM and NAFLD. Jiedu Tongluo Tiaogan Formula (JTTF), based on TCM theory, is widely used in clinical treatment, and its effectiveness in lowering glucose, regulating lipids, improving insulin resistance, and its pathways of action have been demonstrated in previous studies. However, the mechanism of this formula has not been investigated from a metabolomics perspective. Moreover, high-quality clinical studies on T2DM combined with NAFLD are lacking. Therefore, we aim to conduct a clinical trial to investigate the clinical efficacy, safety, and possible pathways of JTTF in the treatment of T2DM combined with NAFLD using metabolomics techniques.

Methods: A total of 98 participants will be recruited to this clinical trial and randomly assigned to either a treatment group (JTTF + conventional basic treatment) or control group (conventional basic treatment) in a 1:1 ratio. Both groups will have received the same lifestyle interventions in the preceding 12 weeks. The primary outcome will be change in visceral fat area and total score on the TCM syndromes efficacy score scale. The secondary outcome will include changes in ultrasound steatosis grade, fibrosis 4 score (FIB-4), metabolic parameters, anthropometric parameters, visceral fat area. In addition, serum and urine samples collected at baseline and at the end of 12 weeks of treatment will be sequentially tested for untargeted and targeted metabolomics.

Discussion: This study will evaluate the efficacy and safety of JTTF, as well as investigate the differential metabolites and possible mechanisms of JTTF treatment in T2DM combined with NAFLD. We hypothesize that patients will benefit from JTTF, which may provide strong evidence for the clinical use of JTTF in the treatment of T2DM and NAFLD, leading to the possibility of further mechanistic exploration.

Clinical Trial Registration: This clinical trial has been registered in China Clinical Trial Registry (ChiCTR 2100051174).

Metabolic associated fatty liver disease is a disease related to sympathetic nervous system activation

Strong evidence from animal and human studies shows that sympathetic nervous system (SNS) activation is a key factor in the development of metabolic associated fatty liver disease (MAFLD). Activation of the sympathetic nervous system plays an important role in the pathogenesis of obesity, metabolic syndrome, diabetes, hypertension, and MAFLD. When genetically susceptible subjects are exposed to a variety of epigenetic changes, their liver damage may develop into MAFLD. Thus, the pathogenesis of MAFLD is complex, involving the complex interaction of insulin resistance, abnormal hormone secretion, obesity, diet, genetic factors, immune activation, gut microbiota, and other factors. In these processes, the role of sympathetic nerves cannot be underestimated. Notably, SNS has been proposed as a therapeutic target for MAFLD by inhibiting sympathetic nerves. It is worthy of further discussion and research.

The Coexistence of Nonalcoholic Fatty Liver Disease and Type 2 Diabetes Mellitus

The incidence of nonalcoholic fatty liver disease (NAFLD) is growing worldwide. Epidemiological data suggest a strong relationship between NAFLD and T2DM. This is associated with common risk factors and pathogenesis, where obesity, insulin resistance and dyslipidemia play pivotal roles. Expanding knowledge on the coexistence of NAFLD and T2DM could not only protect against liver damage and glucotoxicity, but may also theoretically prevent the subsequent occurrence of other diseases, such as cancer and cardiovascular disorders, as well as influence morbidity and mortality rates. In everyday clinical practice, underestimation of this problem is still observed. NAFLD is not looked for in T2DM patients; on the contrary, diagnosis for glucose metabolism disturbances is usually not performed in patients with NAFLD. However, simple and cost-effective methods of detection of fatty liver in T2DM patients are still needed, especially in outpatient settings. The treatment of NAFLD, especially where it coexists with T2DM, consists mainly of lifestyle modification. It is also suggested that some drugs, including hypoglycemic agents, may be used to treat NAFLD. Therefore, the aim of this review is to detail current knowledge of NAFLD and T2DM comorbidity, its prevalence, common pathogenesis, diagnostic procedures, complications and treatment, with special attention to outpatient clinics.

Non-alcoholic fatty liver disease and thrombocytopenia IV: its association with granulocytopenia

Introduction

We have previously shown that some patients present thrombocytopenia (less than 100 × 10⁹/L platelets) in non-alcoholic fatty liver disease (NAFLD). To further explore the nature of this association, we have now analyzed the association of thrombocytopenia with neutropenia (less than 0.5 × 10⁹/L granulocytes) in NAFLD.

Material and methods

Persons with NAFLD were prospectively accrued in the study after February 2018. The presence of NAFLD was defined by both serologic determinations (Fibromax ®) and liver transient elastography (TE/Fibroscan ®).

Results

In 123 consecutive patients with NAFLD without cirrhosis, thrombocytopenia was identified in 20 (16%), whereas neutropenia was identified in 9 (7%). In the subset of 20 patients with NAFLD and thrombocytopenia, granulocytopenia was identified in 5 (25%), whereas in the subset of 9 patients with granulocytopenia, thrombocytopenia was identified in 5 (55%). We found a significant association between thrombocytopenia and both leukopenia and granulocytopenia (OR 8.25, 95% CI 1.9–34.2, p = 0.004).

Conclusions

Both thrombocytopenia and neutropenia were identified in persons with NAFLD and, as there is a significant relationship between these two variables, we speculate that this finding may support the possibility of hypersplenism being involved in the cytopenias found in NAFLD without cirrhosis.

Gut inflammation exacerbates hepatic injury in C57BL/6J mice via gut-vascular barrier dysfunction with high-fat-incorporated meat protein diets

AIM

Meat and its derivatives provide nutrients essential for human health. However, meat consumption, along with excessive fat intake, has been associated with gut inflammation, intestinal barrier dysfunction and alterations in gut microbiota. Herein, we investigated whether and how these changes in the intestinal barrier system affect the gut liver axis and hepatic injury and eventually lead to the progression of liver syndrome such as NAFLD.

METHODS

Mice were fed with high fat (60% kcal) or low fat (12% kcal) along with soybean (control), chicken and pork proteins (HFCH, HFP, LFCH, and LFP) for 12 weeks. The biomarkers for liver injury were investigated after meat protein intake along with the high fat.

FINDINGS

Greater amount of fat vacuoles visible in the H&E staining increased the inflammatory cell infiltration and disorganized liver structures were observed in the HFP-fed mice. Oil Red O staining revealed that the HFP-fed and HFCH-fed mice showed more lipid droplets, confirming the increased hepatic lipid accumulation. Potential serum markers for NAFLD, ALT and AST were increased in the HF meat diet groups. Key genes responsible for hepatic inflammation and lipogenesis, such as MCP-1, IL1-β and TNF-α were upregulated. HF meat protein diet-fed mice exhibited signs of compromised liver with increased levels of endotoxin in the liver and its binding protein in serum, upregulation of TLRs in the liver, and significant increase in TG, TC, LDL-C and HDL-C concentrations.

SIGNIFICANCE

Intestinal inflammation and barrier dysfunction aggravate liver injury and fibrosis due to the intake of HF meat protein diets in mice, which may contribute to the progress of liver injury and associated complications. Gut inflammation may directly contribute to the development of NAFLD, especially of the gut vascular barricade dysfunction.

The effect of 1,25-dihydroxyvitamin D3 on liver damage, oxidative stress, and advanced glycation end products in experimental nonalcoholic- and alcoholic- fatty liver disease

Background/aim

Oxidative stress and advanced glycation end products (AGEs) formation are proposed as effective mechanisms in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD). 1,25(OH)2D3 was proposed to have antioxidant, antiinflammatory and antiglycation properties. In this study, the effect of 1,25(OH)2D3 treatment on oxidative stress parameters and AGEs levels together with hepatic histopathology was investigated in high fructose (HFr) or ethanol (EtOH)-treated rats.

Materials and methods

Rats were treated with fructose (30%) or ethanol (5-20%) in drinking water with and without 1,25(OH)2D3 treatment (5 µg/kg two times a week) for 8 weeks. Insulin resistance (IR), oxidative stress parameters, AGEs, triglyceride (TG), and hydroxyproline (Hyp) levels together with histopathology were investigated in the liver.

Results

1,25(OH)2D3 decreased hepatic reactive oxygen species, lipid and protein oxidation products together with histopathological improvements in HFr- and EtOH-treated rats. 1,25(OH)2D3 treatment was observed to decrease significantly serum and hepatic AGEs in HFr group, and hepatic AGEs in EtOH group.

Conclusion

Our results clearly show that 1,25(OH)2 D3 treatment may be useful in the alleviation of hepatic lesions by decreasing glycooxidant stress in both NAFLD and ALD models created by HFr- and EtOH-treated rats, respectively.

Lactobacillus casei YRL577 combined with plant extracts reduce markers of non-alcoholic fatty liver disease in mice

Probiotics and plant extracts are considered to prevent the development of non-alcoholic fatty liver disease (NAFLD). The present study explores the effects of using both probiotics and plant extracts on NAFLD. The present study evaluated the effects of plant extracts on lipid droplet accumulation and the growth of probiotics in vitro. A C57BL/6 mouse model was used to examine the effects of probiotics and plant extracts on NAFLD. Body weight and food intake were measured. The levels of serum lipids, oxidative stress and the liver injury index were determined using commercial kits. Haematoxylin and eosin staining, GC and real-time PCR were also used for analysis. The results revealed that administration of Lactobacillus casei YRL577 and L. paracasei X11 with resveratrol (RES) or tea polyphenols (TP) significantly reduced the levels of total cholesterol, TAG and LDL-cholesterol and increased the level of the HDL-cholesterol. The groups of L. casei YRL577 with RES and TP also regulated the liver structure, oxidative stress and injury. Furthermore, L. casei YRL577 with TP exhibited a more positive effect towards improving the NAFLD and increased the concentrations of the butyric acid than other three combined groups. L. casei YRL577 with TP up-regulated the mRNA levels of the farnesoid X receptor and fibroblast growth factor 15 and decreased the mRNA levels of the apical Na-dependent bile acid transporter. These findings showed that L. casei YRL577 + TP-modified genes in the intestinal bile acid pathway improved markers of NAFLD.

Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD)-A Condition Associated with Heightened Sympathetic Activation

Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common liver disease affecting a quarter of the global population and is often associated with adverse health outcomes. The increasing prevalence of MAFLD occurs in parallel to that of metabolic syndrome (MetS), which in fact plays a major role in driving the perturbations of cardiometabolic homeostasis. However, the mechanisms underpinning the pathogenesis of MAFLD are incompletely understood. Compelling evidence from animal and human studies suggest that heightened activation of the sympathetic nervous system is a key contributor to the development of MAFLD. Indeed, common treatment strategies for metabolic diseases such as diet and exercise to induce weight loss have been shown to exert their beneficial effects at least in part through the associated sympathetic inhibition. Furthermore, pharmacological and device-based approaches to reduce sympathetic activation have been demonstrated to improve the metabolic alterations frequently present in patients with obesity, MetSand diabetes. Currently available evidence, while still limited, suggests that sympathetic activation is of specific relevance in the pathogenesis of MAFLD and consequentially may offer an attractive therapeutic target to attenuate the adverse outcomes associated with MAFLD.

Effect of exercise on hepatic steatosis: Are benefits seen without dietary intervention? A systematic review and meta-analysis

BACKGROUND

Interventions involving both exercise and dietary modification are effective in reducing steatosis in nonalcoholic fatty liver disease (NAFLD). However, exercise alone may reduce liver fat and is known to have other positive effects on health. The primary aim of this study was to systematically review the effect of exercise alone without dietary intervention on NAFLD and to examine correlations across changes in liver fat and metabolic markers during exercise.

METHODS

Relevant online databases were searched from earliest records to May 2020 by two researchers. Studies were included where the trial was a randomized controlled trial, participants were adults, exercise intervention was longer than 4 weeks, no dietary intervention occurred, and the effect of the intervention on liver fat was quantified via magnetic resonance imaging/proton magnetic resonance spectroscopy.

RESULTS

Of 21 597 studies retrieved, 16 were included involving 706 participants. Exercise was found to have a beneficial effect on liver fat without dietary modification (-2.4%, -3.13 to -1.66) (mean, 95% CI). Pearson correlation showed significant relationships between change in liver fat and change in weight (r = 0.67, P = .007), liver enzymes aspartate aminotransferase (r = 0.76, P = .002) and alanine aminotransferase (r = 0.91, P < .001), and cardiorespiratory fitness VO₂ peak (peak volume oxygen consumption) (r = -0.88, P = .004). By multivariate regression, change in weight and change in VO₂ peak significantly contributed to change in liver fat (R² = 0.84, P = .01).

CONCLUSIONS

This systematic review found that exercise without dietary intervention improves liver fat and that clinical markers may be useful proxies for quantifying liver fat changes.

Nonalcoholic Fatty Liver Disease and Thrombocytopenia III: Its Association With Insulin Resistance

Thrombocytopenia (less than 100 × 10⁹/L platelets) presents in around one quarter of patients with nonalcoholic fatty liver disease (NAFLD), the hepatic component of insulin resistance (IR). It is unknown whether IR, by itself, associates with thrombocytopenia. Persons with NAFLD and/or IR were prospectively accrued in the study after February 2018. Insulin resistance was defined by assessing α hydroxybutyrate, lynoleoyl glycerolphosphocoline, oleic acid, and insulin (Quantose IR), whereas the presence of NAFLD was defined by serologic determinations (Fibromax) and liver transient elastography (Fibroscan). In 78 patients with NAFLD, thrombocytopenia was identified in 22 (28%), whereas in 19 persons with IR, 14 (73%) were found to have NAFLD. In persons with IR + NAFLD, thrombocytopenia presented in 9 (64%). In the subset of patients with IR, the prevalence of thrombocytopenia was 52%. There was only 1 patient with IR/without NAFLD who displayed thrombocytopenia. Significant statistical association between NAFLD and thrombocytopenia was found (odds ratio [OR]: = 13, confidence interval [CI]: 1.5-162, P = .05), whereas there was no association between IR and thrombocytopenia (OR = 0.38, CI: 0.06-2.3, P = .61). Insulin resistance, by itself, was not found to be associated with diminished platelet counts. The presence of NAFLD, one of the consequences of IR, seems to be required to lead into thrombocytopenia.

Immunohistochemical expression of autophagosome markers LC3 and p62 in preneoplastic liver foci in high fat diet-fed rats

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive deposition of droplets in hepatocytes. Patients with NAFLD can be at risk for nonalcoholic steatohepatitis, which can lead to hepatocellular carcinoma. Autophagy is a cellular pathway that is crucial for survival and homeostasis, and which protects against pathophysiological changes like obesity and cancer. We determined the expression of autophagy markers in preneoplastic hepatic lesions and the effects of an autophagy repressor chloroquine (CQ) or inducer amiodarone (AM) in a steatosis-related hepatocarcinogenesis model. Male F344 rats were fed a control diet or high fat diet (HFD), and subjected to initiation and promotion steps with N-nitrosodiethylamine injection at week 0 and a partial hepatectomy at week 3. Several HFD-fed rats were administered 0.1% CQ and 0.5% AM in their drinking water during week 2 and 8. CQ and AM did not improve HFD-induced obesity. AM, but not CQ, significantly decreased the number of glutathione S-transferase placental form-positive preneoplastic liver foci in the liver. Autophagosome markers LC3 and the LC3-binding protein p62 were heterogeneously expressed in the preneoplastic foci. CQ might inhibit autophagy by significantly increased p62/LC3 ratio, while AM might have a potential of inducing autophagy by showing an increased gene expression of the autophagy regulator, Atg5. These results suggest that preneoplastic lesions express autophagosome markers and that AM might decrease steatosis-related early hepatocarcinogenesis by potentially inducing autophagy in HFD-fed rats, while inhibition of autophagy by CQ did not alter the hepatocarcinogenesis. However, an immunohistochemical trial revealed a technical limitation in detecting autophagosome markers because there were variations in each preneoplastic lesion.

Untargeted metabonomics reveals intervention effects of chicory polysaccharide in a rat model of non-alcoholic fatty liver disease

In the current study, serum metabolomics techniques were used to evaluate the potential mechanism of the effect of chicory polysaccharides in non-alcoholic fatty liver disease (NAFLD) rats. A rat model of NAFLD was constructed according to the histopathological data and biochemical parameters, while the underlying mechanisms of high-fat diet (HFD) induced NAFLD and the therapeutic effects of chicory polysaccharides (CP) were studied by the adoption of serum metabolomics. The serum metabolites were analyzed by GC/MS. Multivariate statistical approaches such as principal component analysis, revealed significant differences with HFD model and CP groups against the control. Results indicated that CP plays a regulatory role in the occurrence of NAFLD. Meantime, a total of 65 candidate biomarkers were screened and identified. Cluster analysis, enrichment analysis and metabolic pathway analysis of differential metabolites also indicated that amino acid metabolism and fatty acid biosynthesis in NAFLD rats, the β-oxidation and urea cycle of very long-chain fatty acids were mainly disturbed when compared against the control group. The corresponding metabolic pathways in the CP group were relieved compared against the NAFLD rats. These results showed that untargeted metabonomics helps to explain intervention effects of chicory polysaccharide with the rat model of NAFLD.

Cherry Anthocyanins Regulate NAFLD by Promoting Autophagy Pathway

Nonalcoholic fatty liver disease (NAFLD) is a common chronic disease that threatens human health, and present therapies remain limited due to the lack of effective drugs. Lipid metabolic disturbance and oxidative stress have strong links to the development of NAFLD, while autophagy was generally accepted as a key regulatory mechanism on these steps. Our previous studies indicated that cherry anthocyanins (CACN) protected against high fat diet-induced obesity and NALFD in C57BL/6 mice, while the underlying molecule mechanism is still unclear. Thus, in this study, we show that CACN protect against oleic acid- (OA-) induced oxidative stress and attenuate lipid droplet accumulation in NAFLD cell models. According to the results of a transmission electron microscope (TEM), western blot, immunofluorescence (IF), and adenovirus transfection (Ad-mCherry-GFP-LC3B), autophagy is in accordance with the lipid-lowering effect induced by CACN. Further studies illustrate that CACN may activate autophagy via mTOR pathways. In addition, an autophagy inhibitor, 3-methyladenine (3-MA), was applied and the result suggested that autophagy indeed participates in the lipid clearance process in OA-induced lipid accumulation. All these results indicate that the positive effects of CACN on OA-induced hepatic lipid accumulation are mediated via activating autophagy, showing a potential target for the therapeutic strategy of NAFLD.

Steatosis and steatohepatitis found in adults after death due to non-burn trauma

OBJECTIVE

With the increasing prevalence of steatosis, the number of steatotic liver grafts from deceased donors is also increasing. Thus, determining the prevalence and the population risk factors of steatosis may assist in risk stratification. The aim of this study was to evaluate the prevalence and predictors of steatosis and steatohepatitis among livers from adults who died due to non-burn trauma.

METHODS

Specimens were collected from 224 adults undergoing autopsy at a regional autopsy referral center from September 2011 to April 2013. Histopathological examination was performed on six samples obtained from different lobes of each liver. The outcomes of interest were the presence of steatosis, steatohepatitis, NASH inflammation and NASH fibrosis. The main predictors were body mass index, abdominal circumference, liver weight and volume, presence of cholelithiasis, and siderosis. Our modeling strategy made use of a series of generalized linear models with a binomial family.

RESULTS

Our sample had a mean age of 40 years; steatosis was diagnosed in 48.2% of cases, and steatohepatitis was diagnosed in 2.7%. The presence of a high proportion of fatty changes was more prevalent among males and older individuals, with the most affected age group being 41-60 years. When evaluating the crude odds ratio for steatosis, the factors significantly associated with an increased risk of steatosis were greater abdominal circumference, BMI, and liver weight and the presence of siderosis.

CONCLUSION

Our study reinforces the role of older age, obesity and hepatomegaly as predictors of fatty liver disease. These variables should be considered in the assessment of fatty changes in the livers of potential liver donors.

Efficacy of canagliflozin against nonalcoholic fatty liver disease: a prospective cohort study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a common cause of chronic liver disease worldwide and is characterized by insulin resistance, hepatic steatosis and often prediabetes or diabetes. Canagliflozin, a selective sodium glucose cotransporter 2 inhibitor, is a new oral anti-diabetic drug that reduces hyperglycaemia by promoting urinary glucose excretion. Glycosuria produced by canagliflozin is associated with weight loss, mainly due to reduced fat volume and improve insulin resistance. Reduced body weight and improvement of insulin resistance by canagliflozin may be an effective treatment for NAFLD.

METHODS

Thirty-five patients with NAFLD (17 men and 18 women) were enrolled and administered canagliflozin (100 mg). Body weight and serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transferase (γ-GTP), low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides (TG), blood sugar (BS), glycated haemoglobin (HbA1C), uric acid (UA) and ferritin, and fibrosis-4 (FIB-4) index values were measured at baseline and at 3-month and 6-month follow-up visits.

RESULTS

Body weight and serum levels of AST, ALT, γ-GTP, TG, UA, HbA1C, BS and ferritin decreased significantly after 3 and 6 months of canagliflozin treatment. Serum BS levels and FIB-4 index values decreased slightly following 3 months of treatment; these results reached significance after 6 months. Reduced serum ALT levels at 6 months were significantly correlated with baseline HbA1C and ferritin levels. Moreover, a significant correlation between reduced body weight and serum ALT levels was observed at 6 months. Decreased serum ALT levels were significantly correlated with decreased serum ferritin at 6 months.

CONCLUSIONS

Canagliflozin significantly reduced the serum levels of BS, HbA1C, TG, UA and ferritin, as well as FIB-4 index values and body weight, with improved liver function. Sodium glucose cotransporter 2 inhibitors may be an important therapeutic modality for improving liver injury in NAFLD patients.

Gut inflammation exacerbates hepatic injury in the high-fat diet induced NAFLD mouse: Attention to the gut-vascular barrier dysfunction

AIMS

Gut inflammation has been put forward to be associated with hepatic injury in the clinical practice. The dismantled intestinal barrier was highly concerned, however, largely unknown about the role of gut-vascular barrier (GVB) in this process. This study aimed to investigate if inflamed gut directly contributes to the progression of non-alcoholic steatohepatitis (NASH), especially attention to the GVB dysfunction.

MAIN METHODS

Male C57bl/6 mice were fed with a high-fat diet (HFD) and 1% DSS for 12 weeks. The colonic inflammatory injury as well as hepatic injury were evaluated. The GVB function was assessed via measuring the permeability to fluorescently-labeled dextran (70 kDa) and the expression of plasmalemma vesicle-associated protein-1 (PV1). Furthermore, the plasma endotoxin level and hepatic TLR4/TLR9 mRNA expression were detected.

KEY FINDINGS

There were evident colitis in DSS-exposed mice, which trend to be more apparent in HFD ones. The HFD + DSS mice exhibited more serious hepatic steatosis, inflammation and fibrosis than HFD groups. The downregulated tight junction protein in HFD + DSS mice indicated loss of epithelial barrier. The GVB disruption were also confirmed with increased permeability to macromolecules and high expression of endothelial PV1 in HFD + DSS mice. Accordingly, potentially elevated plasma endotoxin levels and markedly increased TLR4/TLR9 mRNA expression were demonstrated in HFD + DSS mice rather than HFD groups.

SIGNIFICANCE

Gut inflammation exacerbates liver injury and fibrosis in HFD mice, which may contribute to the development of NASH. Beyond the damaged intestinal epithelial barrier, GVB disruption with bacterial translocation into may play a key role in the pathogenesis of NASH.

The Aqueous Extract of Gynura divaricata (L.) DC. Improves Glucose and Lipid Metabolism and Ameliorates Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is a chronic disease characterized by hyperglycemia and dyslipidemia caused by impaired insulin secretion and resistance of the peripheral tissues. A major pathogenesis of T2DM is obesity-associated insulin resistance. Gynura divaricata (L.) DC. (GD) is a natural plant and has been reported to have numerous health-promoting effects on both animals and humans. In this study, we aimed to elucidate the regulatory mechanism of GD improving glucose and lipid metabolism in an obesity animal model induced by high-fat and high-sugar diet in combination with low dose of streptozocin and an insulin-resistant HepG2 cell model induced by dexamethasone. The study showed that the water extract of GD (GD extract A) could significantly reduce fasting serum glucose, reverse dyslipidemia and pancreatic damage, and regulate the body weight of mice. We also found that GD extract A had low toxicity in vivo and in vitro. Furthermore, GD extract A may increase glucose consumption in insulin-resistant HepG2 cells, markedly inhibit NF-κB activation, and decrease the impairment in signaling molecules of insulin pathway, such as IRS-1, AKT, and GLUT1. Overall, the results indicate that GD extract A is a promising candidate for the prevention and treatment of T2DM.

Hyperferritinemia in patients with nonalcoholic fatty liver disease

Objective:

In liver diseases, hyperferritinemia (HYF) is related to injured cells in acquired and genetic conditions with or without iron overload. It is frequent in patients with nonalcoholic fatty liver disease (NAFLD), in which it is necessary to define the mean of HYF to establish the better approach for them. The present study evaluated the significance of elevated ferritin in patients with NAFLD and steatohepatitis (NASH).

Method:

The review was performed using search instruments of indexed scientific material, including MEDLINE (by PubMed), Web of Science, IBECS and LILACS, to identify articles published in Portuguese, English and Spanish, from 2005 to May, 2016. Studies eligible included place and year of publication, diagnose criteria to NAFLD, specifications of serum ferritin measurements and/or liver histopathologic study. Exclusion criteria included studies with patients with alcohol consumption ≥ 20 g/day and other liver diseases.

Results:

A total of 11 from 30 articles were selected. It included 3,564 patients and they were cross-sectional, retrospective, case series and case-control. The result's analyses showed in 10 of these studies a relationship between ferritin elevated serum levels and NAFLD/NASH with and without fibrosis and insulin resistance.

Conclusion:

Hyperferritinemia in patients with NAFLD/NASH is associated more frequently with hepatocellular injury than hemochromatosis. These data suggest the relevance to evaluate carefully HYF in patients with NAFLD/NASH to establish appropriate clinical approach.

The pharmacological management of NAFLD in children and adolescents

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) represents a spectrum, including 'simple' steatosis, non-alcoholic steatohepatitis (NASH), and fibrosis. Increasing prevalence of NAFLD has followed the international rise in obesity and lifestyle modification is the mainstay therapy for children. To date, pharmacological trials have had varying efficacy but a large number of new agents are in early phase trials for adults. Areas covered: This review explores the effect of current and potential future paediatric NAFLD treatments in terms of histological and biochemical endpoints. The potential for the extension of adult treatments to children is discussed, as well as what limits the use of certain agents in children. Expert commentary: No drugs have yet to be licenced for NAFLD. Trial heterogeneity makes comparison of drugs between studies challenging. FXR agonists are yet to be trialled in children but may represent a safe and potentially efficacious therapy. Future treatments would likely encompass a multimodal approach that may include bariatric surgery.

RNA helicase DDX3 maintains lipid homeostasis through upregulation of the microsomal triglyceride transfer protein by interacting with HNF4 and SHP

Multifunctional RNA helicase DDX3 participates in HCV infection, one of the major causes of hepatic steatosis. Here, we investigated the role of DDX3 in hepatic lipid metabolism. We found that HCV infection severely reduced DDX3 expression. Analysis of intracellular triglyceride and secreted ApoB indicated that lipid accumulations were increased while ApoB secretion were decreased in DDX3 knockdown HuH7 and HepG2 cell lines. Down-regulation of DDX3 significantly decreased protein and transcript expression of microsomal triglyceride transfer protein (MTP), a key regulator of liver lipid homeostasis. Moreover, DDX3 interacted with hepatocyte nuclear factor 4 (HNF4) and small heterodimer partner (SHP), and synergistically up-regulated HNF4-mediated transactivation of MTP promoter via its ATPase activity. Further investigation revealed that DDX3 interacted with CBP/p300 and increased the promoter binding affinity of HNF4 by enhancing HNF4 acetylation. Additionally, DDX3 partially relieved the SHP-mediated suppression on MTP promoter by competing with SHP for HNF4 binding which disrupted the inactive HNF4/SHP heterodimer while promoted the formation of the active HNF4 homodimer. Collectively, these results imply that DDX3 regulates MTP gene expression and lipid homeostasis through interplay with HNF4 and SHP, which may also reveal a novel mechanism of HCV-induced steatosis.

High-fat diet plus carbon tetrachloride-induced liver fibrosis is alleviated by betaine treatment in rats

Steatosis, the first lesion in non-alcoholic fatty liver disease (NAFLD), may progress to fibrosis, cirrhosis, and hepatocellular carcinoma. Steatosis predisposes the liver to oxidative stress, inflammation, and cytokines. Betaine (BET) has antioxidant, antiinflammatory and hepatoprotective effects. However, the effects of BET on liver fibrosis development are unknown. Rats were treated with high-fat diet (60% of total calories from fat) for 14weeks. Carbon tetrachloride (0.2mL/kg; two times per week; i.p.) was administered to rats in the last 6weeks with/without commercial food containing BET (2%; w/w). Serum liver function tests and tumor necrosis factor-α, insulin resistance, hepatic triglyceride (TG) and hydroxyproline (HYP) levels and oxidative stress parameters were determined along with histopathologic observations. Alpha-smooth muscle-actin (α-SMA), transforming growth factor-β1 (TGF-β1) and type I collagen (COL1A1) protein expressions and mRNA expressions of matrix metalloproteinase-2 (MMP-2) and its inhibitors (TIMP-1 and TIMP-2) were evaluated. BET decreased TG and HYP levels, prooxidant status and fibrotic changes in the liver. α-SMA, COL1A1 and TGF-β1 protein expressions, MMP-2, TIMP-1, and TIMP-2 mRNA expressions diminished due to BET treatment. BET has an antifibrotic effect and this effect may be related to its antioxidant and antiinflammatory actions together with suppression on HSC activation.

Adipose tissue-derived stem cells promote the reversion of non-alcoholic fatty liver disease: An in vivo study

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of liver injury and seriously affects human health. In the present study, we aimed to investigate whether adipose tissue-derived stem cell (ADSC) transplantation in combination with dietary modification was capable of reversing the progression of NAFLD. After establishing a rat model of NAFLD by feeding them a high-fat diet (HFD), ADSCs were transplanted via the portal vein into rats with HFD-induced NAFLD, and simultaneously fed a modified diet. Thereafter, gross liver morphology, the hepatosomatic (HSI) index and indicators of liver function, including alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL) were evaluated. Subsequently, the serum levels of total cholesterol (TC), triglycerides (TGs) and fatty acids (FAs) were also assayed. Furthermore, H&E and oil red O staining were used to confirm the pathological effects of NAFLD in the rat livers. Although dietary modification alone caused liver function to recover, ADSC transplantation in combination with dietary modification further decreased the HSI index, the serum levels of ALT, TBIL, TC, TGs, FAs, reduced lipid accumulation to normal levels, and reversed the hepatic pathological changes in the rat livers. Taken together, these findings suggest that ADSC transplantation assists in the reversion of NAFLD by improving liver function and promoting lipid metabolism, thereby exerting hepatoprotective effects. Thus, we suggest that ADSC transplantation is a promising, potential therapeutic strategy for NAFLD treatment.

Current Pharmacologic Therapy for Nonalcoholic Fatty Liver Disease

Weight loss, regular exercise, and diet composition modification seem to improve biochemical and histologic abnormalities. Other therapies directed at insulin resistance, oxidative stress, cytoprotection, and fibrosis may also offer benefits. Insulin sensitizers and vitamin E seem to be the most promising; however, they cause side effects. A multifaceted approach of lifestyle modifications, weight loss, and pharmacotherapy can be used in combination, but no single treatment approach has proved universally applicable to the general population with nonalcoholic steatohepatitis (NASH). Continuous clinical and preclinical studies on existing and potential drugs are needed to improve treatment of nonalcoholic fatty liver disease/NASH.

Relationship between hepatic ischemia-reperfusion injury and lipid peroxidation

Hepatic ischemia-reperfusion injury results in a mixture of apotosis or necrosis which are caused by various mechanisms such as mitochondrial injury, endoplasmic reticulum stress, burst of reactive oxygen species, calcium overload, and release of various cytokines that induce the change of intracellular or extracellular signal transduction pathways. Lipid peroxidation can be described generally as a process in which oxidants such as free radicals attack lipids containing carbon-carbon double bond(s), especially polyunsaturated fatty acids (PUFAs) which manily form the plasma membrane system. Lipid peroxidation occurring throughout the entire biological reaction process during HIRI, especially the mitochondrial lipid peroxidation, may be the central molecular event that is worthy of further exploration and research.

Glycosyltransferases and non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease and its incidence is increasing worldwide. However, the underlying mechanisms leading to the development of NAFLD are still not fully understood. Glycosyltransferases (GTs) are a diverse class of enzymes involved in catalyzing the transfer of one or multiple sugar residues to a wide range of acceptor molecules. GTs mediate a wide range of functions from structure and storage to signaling, and play a key role in many fundamental biological processes. Therefore, it is anticipated that GTs have a role in the pathogenesis of NAFLD. In this article, we present an overview of the basic information on NAFLD, particularly GTs and glycosylation modification of certain molecules and their association with NAFLD pathogenesis. In addition, the effects and mechanisms of some GTs in the development of NAFLD are summarized.

Wild ginseng cambial meristematic cells ameliorate hepatic steatosis and mitochondrial dysfunction in high-fat diet-fed mice

Objectives

The aim of this study was to determine the protective mechanisms of wild ginseng cambial meristematic cells (CMCs) on non-alcoholic fatty liver disease in high-fat diet (HFD)-fed mice.

Methods

Male C57BL/6 mice received either normal-fat diet or HFD for 10 weeks along with wild ginseng CMCs (75, 150 and 300 mg/kg) or vehicle (0.5% carboxyl methyl cellulose) by oral administration once a day. Triglyceride and total cholesterol contents were measured in liver and serum samples. Parameters for hepatic lipid metabolism and mitochondria biogenesis were assessed.

Key findings

Treatment with wild ginseng CMCs markedly attenuated body weight, serum and hepatic lipid contents, and serum aminotransferase activity. While wild ginseng CMCs attenuated the increases in sterol regulatory element-binding transcription factor 1 (SREBP-1) and carbohydrate-responsive element-binding protein (ChREBP) expression, it enhanced the increases in carnitine palmitoyltransferase 1A (CPT1A) and peroxisome proliferator-activated receptor alpha (PPAR-α) expression. HFD decreased glutamate dehydrogenase activity and glutathione content, and increased lipid peroxidation, which were all attenuated by wild ginseng CMCs. Furthermore, wild ginseng CMCs enhanced mitochondrial biogenesis-related factors, including peroxisome proliferator-activated receptor-γ co activator 1α (PGC1α), nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM).

Conclusions

Wild ginseng CMCs protect against HFD-induced liver injury, which prevents lipid accumulation and mitochondrial oxidative stress, and enhances mitochondrial biogenesis.

Is Liver Enzyme Release Really Associated with Cell Necrosis Induced by Oxidant Stress?

Hepatic diseases are a major concern worldwide. Increased specific plasma enzyme activities are considered diagnostic features for liver diseases, since enzymes are released into the blood compartment following the deterioration of the organ. Release of liver mitochondrial enzymes is considered strong evidence for hepatic necrosis, which is associated with an increased production of ROS, often leading to greater hepatic lipid peroxidation. Lipotoxic mediators and intracellular signals activated Kupffer cells, which provides evidence strongly suggesting the participation of oxidant stress in acute liver damage, inducing the progression of liver injury to chronic liver damage. Elevated transaminase activities are considered as an index marker of hepatotoxicity, linked to oxidant stress. However, a drastic increase of serum activities of liver enzyme markers ought not necessarily to reflect liver cell death. In fact, increased serum levels of cytoplasmic enzymes have readily been observed after partial hepatectomy (PH) in the regenerating liver of rats. In this regard, we are now showing that in vitro modifications of the oxidant status affect differentially the release of liver enzymes, indicating that this release is a strictly controlled event and not directly related to the onset of oxidant stress of the liver.

Intrahepatic transplantation of adipose-derived stem cells attenuates the progression of non-alcoholic fatty liver disease in rats

Non‑alcoholic fatty liver disease (NAFLD) is one of the major causes of chronic liver injury affecting the general health of various populations. In the present study, adipose tissue‑derived stem cells (ADSCs), which were isolated from the adipose tissues of Sprague‑Dawley rats, were transplanted into the liver of high‑fat‑diet‑induced NAFLD rats via the portal vein to attenuate the disease progression of NAFLD. The results demonstrated that ADSC transplantation reduced the serum levels of alanine aminotransferase, total bilirubin, total cholesterol, triglycerides and fatty acids, and reduced the content of malondialdehyde in the liver homogenates. By contrast, ADSC transplantation caused a significant increase in superoxide dismutase activity. These data suggested that the ADSC transplantation improved the liver function, and reduced lipid metabolism and oxidative stress. In addition, the hepatic pathological changes were decelerated, lipid accumulation was reduced, and serum levels of the pro‑inflammatory factors, tumor necrosis factor‑α and interleukin‑6, were downregulated by the ADSC transplantation. Taken together, transplantation with ADSCs attenuates the disease progression of high‑fat‑diet induced NAFLD, therefore, may offer a potential therapeutic approach for the treatment of NAFLD.

Protective effects of Ginkgo biloba leaf polysaccharide on nonalcoholic fatty liver disease and its mechanisms

A water-soluble polysaccharide fraction extracted from the leaf of Ginkgo biloba was named GBLP. The protective effect of GBLP on nonalcoholic fatty liver disease (NAFLD) was observed and underlying mechanism was explored. Wistar male rats were randomly divided into five groups, namely, normal control group, model control group and GBLP groups (100, 200 and 400 mg/kg/d). A rat model of NAFLD was established in male Wistar rats by feeding with high-fat diet (HFD) for 8 weeks. On day 57, the intragastric administration of GBLP started once daily for 4 weeks. The results showed that GBLP supplementation significantly and dose-dependently lowered the weight gain of body, liver index and serum lipid parameters in HFD-fed rat. Meanwhile, GBLP attenuated HFD-induced liver injury through reducing hepatic steatosis, TG accumulation, serum ALT, AST and ALP levels. GBLP had a positive effect on obesity-associated insulin resistance (IR) via reducing serum glucose and insulin levels. Furthermore, GBLP enhanced the activities of antioxidant enzymes and reduced MDA levels in serum and liver. These results indicate that GBLP can play a certain protective role against HFD-induced NAFLD, and the protective effects may be associated with attenuating IR, preserving liver function, enhancing antioxidant defense system, and reducing lipid peroxidation.

Dihydromyricetin improves glucose and lipid metabolism and exerts anti-inflammatory effects in nonalcoholic fatty liver disease: A randomized controlled trial

Ampelopsis grossedentata, a medicinal and edible plant, has been widely used in China for hundreds of years, and dihydromyricetin is the main active ingredient responsible for its various biological actions. We investigated the effects of dihydromyricetin on glucose and lipid metabolism, inflammatory mediators and several biomarkers in nonalcoholic fatty liver disease. In a double-blind clinical trial, sixty adult nonalcoholic fatty liver disease patients were randomly assigned to receive either two dihydromyricetin or two placebo capsules (150 mg) twice daily for three months. The serum levels of alanine, aspartate aminotransferase, γ-glutamyl transpeptidase, glucose, low-density lipoprotein-cholesterol and apolipoprotein B, and the homeostasis model assessment of insulin resistance (HOMA-IR) index were significantly decreased in the dihydromyricetin group compared with the placebo group. In the dihydromyricetin group, the serum levels of tumor necrosis factor-alpha, cytokeratin-18 fragment and fibroblast growth factor 21 were decreased, whereas the levels of serum adiponectin were increased at the end of the study. We conclude that dihydromyricetin supplementation improves glucose and lipid metabolism as well as various biochemical parameters in patients with nonalcoholic fatty liver disease, and the therapeutic effects of dihydromyricetin are likely attributable to improved insulin resistance and decreases in the serum levels of tumor necrosis factor-alpha, cytokeratin-18, and fibroblast growth factor 21.

Resveratrol improves hepatic steatosis by inducing autophagy through the cAMP signaling pathway

SCOPE

Resveratrol (RSV), a natural polyphenol, has been reported to attenuate nonalcoholic fatty liver disease (NAFLD); however, its underlying mechanism is unclear. Autophagy was recently identified as a critical protective mechanism during NAFLD development. Therefore, we investigated the role of autophagy in the beneficial effects of RSV on hepatic steatosis.

METHODS AND RESULTS

Via Oil red O staining, triglyceride, and β-hydroxybutyrate detection, we found that RSV decreased palmitate-induced lipid accumulation and stimulated fatty acid β-oxidation in hepatocytes. Based on Western blot assay, confocal microscopy and transmission electron microscopy, we found that RSV induced autophagy in hepatocytes, whereas autophagy inhibition markedly abolished RSV-mediated hepatic steatosis improvement. Moreover, RSV increased cAMP levels and the levels of SIRT1 (sirtuin 1), pPRKA (phosphorylated protein kinase A), and pAMPK (phosphorylated AMP-activated protein kinase), as well as SIRT1 activity in HepG2 cells. Incubation with inhibitors of AC (adenylyl cyclase), PRKA, AMPK, SIRT1, or with AC, PRKA, AMPK, or SIRT1 siRNA abolished RSV-mediated autophagy. Similar results were obtained in mice with hepatic steatosis.

CONCLUSION

RSV improved hepatic steatosis partially by inducing autophagy via the cAMP-PRKA-AMPK-SIRT1 signaling pathway, which provides new evidence regarding RSV's effects on NAFLD treatment.

Effect of nuclear factor-κB and angiotensin II receptor type 1 on the pathogenesis of rat non-alcoholic fatty liver disease

AIM: To investigate the roles of nuclear factor (NF)-κB and angiotensin II receptor type 1 (AT1R) in the pathogenesis of non-alcoholic fatty liver disease (NAFLD).

METHODS: Forty-two healthy adult male Sprague-Dawley rats were randomly divided into three groups: the control group (normal diet), the model group, and the intervention group (10 wk of a high-fat diet feeding, followed by an intraperitoneal injection of PDTC); 6 rats in each group were sacrificed at 6, 10, and 14 wk. After sacrifice, liver tissue was taken, paraffin sections of liver tissue specimens were prepared, hematoxylin and eosin (HE) staining was performed, and pathological changes in liver tissue (i.e., liver fibrosis) were observed by light microscopy. NF-κB expression in liver tissue was detected by immunohistochemistry, and the expression of AT1R in the liver tissue was detected by reverse transcription-polymerase chain reaction (RT-PCR). The data are expressed as mean ± SD. A two-sample t test was used to compare the control group and the model group at different time points, paired t tests were used to compare the differences between the intervention group and the model group, and analysis of variance was used to compare the model group with the control group. Homogeneity of variance was analyzed with single factor analysis of variance. H variance analysis was used to compare the variance. P < 0.05 was considered statistically significant.

RESULTS: The NAFLD model was successful after 6 wk and 10 wk. Liver fibrosis was found in four rats in the model group, but in only one rat in the intervention group at 14 wk. Liver steatosis, inflammation, and fibrosis were gradually increased throughout the model. In the intervention group, the body mass, rat liver index, serum lipid, and transaminase levels were not increased compared to the model group. In the model group, the degree of liver steatosis was increased at 6, 10, and 14 wk, and was significantly higher than in the control group (P < 0.01). In the model group, different degrees of liver cell necrosis were visible and small leaves, punctated inflammation, focal necrosis, and obvious ballooning degeneration were observed. Partial necrosis and confluent necrosis were observed. In the model group, liver inflammatory activity scores at 6, 10, and 14 wk were higher than in the control group (P < 0.01). Active inflammation in liver tissue in the intervention group was lower than in the model group (P < 0.05). HE staining showed liver fibrosis only at 14 wk in 4/6 rats in the model group and in 1/6 rats in the intervention group. NF-κB positive cells were stained yellow or ensemble yellow, and NF-κB was localized in the cytoplasm and/or nucleus. The model group showed NF-κB activation at 6, 10, and 14 wk in liver cells; at the same time points, there were statistically significant differences in the control group (P < 0.01). Over time, NF-κB expression increased; this was statistically lower (P < 0.05) at 14 weeks in the intervention group compared to the model group, but significantly increased (P < 0.05) compared with the control group; RT-PCR showed that AT1R mRNA expression increased gradually in the model group; at 14 wk, the expression was significantly different compared with expression at 10 weeks as well as at 6 weeks (P < 0.05). In the model group, AT1R mRNA expression was significantly higher than at the same time point in the control group (P < 0.01).

CONCLUSION: With increasing severity of NAFLD, NF-κB activity is enhanced, and the inhibition of NF-κB activity may reduce AT1R mRNA expression in NAFLD.

The Hexane Fraction of Cyperus rotundus Prevents Non-Alcoholic Fatty Liver Disease Through the Inhibition of Liver X Receptor α-Mediated Activation of Sterol Regulatory Element Binding Protein-1c

The goals of this study were (1) to examine the effects of Cyperus rotundus (CR) rhizome on cellular lipogenesis and non-alcoholic/diet-induced fatty liver disease, and (2) to elucidate the molecular mechanism behind its actions. The present investigation showed that the hexane fraction of CR rhizome (CRHF) reduced the elevated transcription levels of sterol regulatory element binding protein-1c (SREBP-1c) in primary hepatocytes following exposure to the liver X receptor α (LXRα) agonist. The SREBP-1c gene is a master regulator of lipogenesis and a key target of LXRα. CRHF inhibited not only the LXRα-dependent activation of the synthetic LXR response element (LXRE) promoter, but also the activation of the natural SREBP-1c promoter. Moreover, CRHF decreased (a) the recruitment of RNA polymerase II to the LXRE of the SREBP-1c gene; (b) the LXRα-dependent up-regulation of various lipogenic genes; and (c) the LXRα-mediated accumulation of triglycerides in primary hepatocytes. Furthermore, CRHF ameliorated fatty liver disease and reduced the expression levels of hepatic lipogenic genes in high sucrose diet (HSD)-fed mice. Interestingly, CRHF did not affect the expression of ATP-binding cassette transporter A1, another important LXR target gene that is required for reverse cholesterol transport (RCT) and protects against atherosclerosis. Taken together, these results suggest that CRHF might be a novel therapeutic remedy for fatty liver disease through the selective inhibition of the lipogenic pathway.

Hypercholesterolemic diet induces hepatic steatosis and alterations in mRNA expression of NADPH oxidase in rat livers

OBJECTIVE

This study aimed to determine whether a hypercholesterolemic diet induces hepatic steatosis, alterations in mRNA expression of NADPH oxidase subunits, and antioxidant defenses.

MATERIALS AND METHODS

Fischer rats were divided into two groups of eight animals according to the treatment, control (C) and hypercholesterolemic diet (H). Those in group C were fed a standard diet (AIN-93M), and those of the group H were fed a hypercholesterolemic diet (25% soybean oil and 1% cholesterol).

RESULTS

The hypercholesterolemic diet did not affect body weight, but resulted in the accumulation of lipids in the liver, increased serum activities of aminotransferases and cholesterol levels. Biomarker of lipid peroxidation (TBARS) and mRNA expression of NADPH oxidase subunits p22(phox) and p47(phox) were increased in the liver of animals in group H. Besides, the activity and expression of antioxidant enzymes were altered.

CONCLUSION

The results show increased mRNA expression of NADPH oxidase subunits and changes in antioxidant enzyme activities in diet-induced hepatic steatosis.

Current pharmacological therapies for nonalcoholic fatty liver disease/nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) is considered to be a hepatic manifestation of metabolic syndrome, and its incidence is rapidly increasing worldwide. It is currently the most common chronic liver disease. NASH can progress to liver cirrhosis and hepatocellular carcinoma, and may result in liver-related death. Currently, the principal treatment for NAFLD/NASH is lifestyle modification by diet and exercise. However, pharmacological therapy is indispensable because obese patients with NAFLD often have difficulty maintaining improved lifestyles. The pathogenesis of NAFLD/NASH has not been completely elucidated. However, insulin resistance, inflammatory cytokines, and oxidative stress are thought to be important in the development and/or progression of the disease. Currently, insulin sensitizers (thiazolidinediones) and antioxidants (vitamin E) seem to be the most promising therapeutic agents for NAFLD/NASH, and lipid-lowering drugs, pentoxifylline, angiotensin receptor blockers, and n-3 polyunsaturated fatty acids also have promise. However, there is a lack of consensus regarding the most effective and appropriate pharmacotherapy for NAFLD/NASH. Animal experiments suggest that herbal medicines and natural products may be promising therapeutic agents for NAFLD/NASH, but their efficacy and safety are yet to be investigated in human studies. In this paper, we review the existing and potential pharmacological therapies for NAFLD/NASH.

Trends in outpatient resource utilizations and outcomes for Medicare beneficiaries with nonalcoholic fatty liver disease

BACKGROUND AND AIM

Nonalcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease. The objective of this study was to describe the recent trend of health care resource utilization and short-term mortality of Medicare beneficiaries with NAFLD.

METHODS

This study utilized data from a random sample of national outpatient claims of Medicare beneficiaries (2005 to 2010) who sought outpatient care for NAFLD.

RESULTS

This study included 29,528 patients who sought outpatient care for NAFLD from 2005 to 2010. The annual number of patients increased consistently from 3585 in 2005 to 6646 in 2010. The prevalence of studied comorbidities including cardiovascular disease, diabetes, hyperlipidemia, and hypertension also increased significantly. At the same time, the mean yearly charge and the mean yearly payment increased significantly from $2624±$3308 and $561±$835 in 2005 to $3608±$5132 and $629±$1157 (P<0.05), respectively. The observed mortality rate remained stable around 2.84% (P=0.64). After adjusting for the other covariates, the total number of outpatient visits and all the comorbidities considered were the most determinant factors for yearly charge and yearly payment (P<0.0001). Overall mortality was associated with age, gender, number of outpatient visits, diabetes, and hyperlipidemia.

CONCLUSIONS

The number of outpatient visits because of NAFLD rose between 2005 and 2010. Short-term mortality rates remained stable throughout the study period, whereas total annual charges and payments increased.

SIRT3 as a Regulator of Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a hepatic presentation of obesity and metabolic syndrome. NAFLD includes a large spectrum of hepatic pathologies that range from simple steatosis and non-alcoholic steatohepatitis (NASH), to liver cirrhosis without an all-encompassing approved therapeutic strategy. Mitochondrial dysfunction is a key component of many metabolic diseases, such as obesity, type 2 diabetes, cancer, NAFLD, and aging. Sirtuin 3 (SIRT3) is a NAD⁺-dependent deacetylase that regulates many of the mitochondrial proteins that are involved with metabolic homeostasis, oxidative stress, and cell survival. This review discusses the association between mitochondrial dysfunction and insulin resistance and later explore the possibility that SIRT3 plays a protective role against NAFLD by improving mitochondrial dysfunction.

Endoplasmic reticulum stress in hepatic steatosis and inflammatory bowel diseases

As an adaptive response to the overloading with misfolded proteins in the endoplasmic reticulum (ER), ER stress plays critical roles in maintaining protein homeostasis in the secretory pathway to avoid damage to the host. Such a conserved mechanism is accomplished through three well-orchestrated pathways known collectively as unfolded protein response (UPR). Persistent and pathological ER stress has been implicated in a variety of diseases in metabolic, inflammatory, and malignant conditions. Furthermore, ER stress is directly linked with inflammation through UPR pathways, which modulate transcriptional programs to induce the expression of inflammatory genes. Importantly, the inflammation induced by ER stress is directly responsible for the pathogenesis of metabolic and inflammatory diseases. In this review, we will discuss the potential signaling pathways connecting ER stress with inflammation. We will also depict the interplay between ER stress and inflammation in the pathogenesis of hepatic steatosis, inflammatory bowel diseases and colitis-associated colon cancer.

Contributions of metabolic dysregulation and inflammation to nonalcoholic steatohepatitis, hepatic fibrosis, and cancer

PURPOSE OF REVIEW

We review accumulating evidence that nonalcoholic steatohepatitis (NASH), a more advanced form of nonalcoholic fatty liver disease (NAFLD), predisposes patients to the risk of developing hepatocellular carcinoma (HCC), and we summarize recent advances in the elucidation of cancer-promoting pathways in NASH. We highlight the potential role of progenitor cells and hepatic stellate cells (HSCs) in promoting the early events that could culminate in cancer, as well as the emerging contribution of the gut-liver axis in promoting inflammation, senescence, and tumor growth in NASH and HCC. Finally, we review the role of bile acid receptors, vitamin D, and protective cellular pathways such as autophagy.

RECENT FINDINGS

Studies have recently uncovered roles for gut microbiota, bile acid receptors and vitamin D in regulating the progression from NAFLD to HCC. Intriguing findings linking senescence and autophagy in hepatic stellate cells to HCC have also been discovered, as well as a link between dysregulated progenitor cell regulation and HCC.

SUMMARY

NAFLD is the most common cause of chronic liver disease in the United States and Western Europe. The lack of definitive mechanisms underlying development of NASH among patients with NAFLD and its progression to HCC limit diagnosis and management, but new findings are paving the way for better biomarkers and therapies.

Pinus densiflora Sieb. et Zucc. alleviates lipogenesis and oxidative stress during oleic acid-induced steatosis in HepG2 cells

Excess accumulation of lipids and oxidative stress in the liver contribute to nonalcoholic fatty liver disease (NAFLD). We hypothesized that Pinus densiflora Sieb. et Zucc. (PSZ) can protect against NAFLD by regulating lipid accumulation and oxidative stress in the liver. To investigate the effect of PSZ upon NAFLD, we used an established cellular model: HepG2 cells treated with oleic acid. Then, the extent of hepatic steatosis and oxidative stress was assessed and levels of inflammatory markers measured. Oleic acid-treated HepG2 cells, compared with controls, had greater lipid accumulation. PSZ decreased lipid accumulation by 63% in oleic acid-treated HepG2 cells. Additionally, PSZ decreased the target gene expression of lipogenesis such as sterol regulatory element binding protein-1c, fatty acid synthase, stearoyl-CoA desaturase-1, diacylglycerol O-acyltransferase-1, and acetyl-CoA carboxylase-1 by 1.75, 6.0, 2.32, 1.93 and 1.81 fold, respectively. In addition, Oleic acid-treated HepG2 cells elicited extensive accumulation of tumor necrosis factor-α (TNFα) by 4.53 fold, whereas PSZ-treated cells decreased the expression of TNFα mRNA by 1.76 fold. PSZ significantly inhibited oxidative stress induced by reactive oxygen species. These results suggest that PSZ has effects on steatosis in vitro and further studies are needed in vivo to verify the current observations.