Effects of estrogen and androgen deprivation on the progression of non-alcoholic steatohepatitis (NASH) in male Sprague–Dawley rats

Aim:  We studied the mechanisms of estrogen/androgen involvement in the induction of NASH by treating Sprague–Dawley (SD) rats fed with a normal or high fat (HF) diet by depriving them of endogenous estrogens/androgens.
Methods:  Male adult SD rats ( n  = 10/group) on normal or HF diets were treated for 75 days either with tamoxifen (Tam) or flutamide (Flu) or Tam + Flu in order to induce NASH. We analyzed histopathologically the liver samples from the treated groups for NASH, checked the serum biochemical and lipid profile markers and finally analyzed the signal pathways underlying the molecular mechanisms for the induction process of NASH.
Results:  Deprivation of endogenous estrogens and/or androgens (Tam or Flu or Tam + Flu) without the HF diet did not induce NASH. Tam or Tam + Flu induced NASH, compared to milder lesions without fibrosis in HF diet and Flu-treated liver. Serum alanine aminotransferase or lipid profile markers further proved the Tam, Flu or Tam + Flu effects on the induction of NASH in conjunction with a HF diet. Tam treatment predominantly downregulated the ERα and FAS and upregulated UCP2 and TNF-α.
Conclusions:  Deprivation of endogenous estrogen/androgens in conjunction with a HF diet may induce NASH where the downregulated ERα and FAS, and upregulated UCP2 and TNF-α could be involved in their molecular pathomechanism pathways. These results could suggest the potential negative roles of estrogenic/androgenic depriving compounds in the induction of NASH, along with obesity.     

Predictors of fibrosis in Asian patients with non-alcoholic steatohepatitis

Background and Aim: Non‐alcoholic steatohepatitis (NASH) is increasingly recognized as an important cause of chronic liver disease. However, data on Asians with NASH is lacking in the literature. The aim of the present study was to describe the clinical, biochemical and histological characteristics of NASH in Asians and to determine the predictors for septal fibrosis. Method: Sixty consecutive patients aged over 18 years with elevated serum alanine transferase, sonographic evidence of steatosis, and consent for liver biopsy were included. Patients with chronic hepatitis B or C, alcoholic, autoimmune, genetic, or drug‐induced liver disease were excluded. Clinical, biochemical and histological variables were tested for association with septal liver fibrosis (F2/3). Results: Median age of the cohort was 45.5 years (range 21–75 years) and 63% were male. Ninety percent of patients were obese (body mass index [BMI]≥ 25), 70% had hypertriglyceridemia, 68% had hypercholesterolemia, 58% had metabolic syndrome, 53% had hypertension, 47% had diabetes mellitus (DM), and 18% had obstructive sleep apnea. Sixty‐eight percent had gamma‐glutamyl transferase (GGT) ≥ 2 × upper limit of normal (ULN), 55% had alanine aminotransferase (ALT) ≥ 2 × ULN, and 23% had aspartate aminotransferase (AST) ≥ 2 × ULN. Of the 40 non‐diabetic patients undergoing oral glucose tolerance testing, 45% had normal tests, 30% had impaired glucose tolerance, 23% DM, and 2% impaired fasting glucose. Eighteen patients (30%) had septal fibrosis (F2/3), but none had cirrhosis. Necroinflammatory grade ≥ 2 (odds ratio [OR] 13), AST ≥ 2 × ULN (OR 5.3) and DM (OR 5) were significantly and independently correlated with septal fibrosis. Conclusion: Septal fibrosis is common in Asians with NASH. Necroinflammatory grade ≥ 2, AST ≥ 2 × ULN and DM are independent predictors for septal fibrosis.     

Influence of age and gender in Japanese patients with non-alcoholic steatohepatitis

Aim: Nonalcoholic steatohepatitis (NASH) is considered to be a manifestation of metabolic syndrome. Because prevalence and severity of metabolic syndrome are different according to ages, gender and ethnic group, it is speculated that the clinicopathological features of NASH may also vary in relation to these factors. The present study was performed to clarify the influence of age and gender on the development of Japanese NASH. Subjects: One hundred 93 biopsy-proven NASH patients (86 women and 107 men) were included in this cross-sectional study. The patients were separately analyzed by generation; a younger group (<55 years old) and an older group (>/=55 years old). These groups were compared for their clinical and histological features. Independent risk factors for advanced fibrosis were also analyzed. Results: Comparison of our younger and older groups showed that older patients had much more advanced fibrosis than the younger ones (advanced fibrosis: 23.8%; youngergroup vs. 54.3%; older group, P < 0.001). Women were predominant in the older group (23.8%; younger group vs. 67.4%; older group, P < 0.001). According to the multivariate analysis for risk factors for advanced fibrosis, age (P = 0.007) and BMI (P = 0.028) were independent predictors of advanced fibrosis in the younger group. In contrast, the absence of hyperlipidemia (P = 0.042) was the only significant independent predictor of advanced fibrosis in the older group. Gender was not a risk factor for the severity of NASH. Conclusions: Clinicians need to be aware of age- and gender-specific differences when assessing the characteristics of NASH, and the findings may be useful for prevention and treatment of this disease.     

Non-alcoholic fatty liver disease: an overview

Non-alcoholic fatty liver disease (NAFL) includes a spectrum of clinicopathological conditions with increasing prevalence in the developed world. Although steatosis alone seems to have a benign course, those patients with the diagnosis of non-alcoholic steatohepatitis (NASH) can have a progressive course. Additionally, there is now evolving, indirect evidence that some of the patients with cryptogenic cirrhosis may be the result of 'burned-out' NASH. Although NAFL and NASH are associated with insulin-resistance syndrome, some patients with NAFL may have no obvious risk factors. Despite preliminary data from a number of pilot studies, no established therapies can be offered to patients with NASH. Over the next few years, a number of exciting research projects dealing with the epidemiology as well as the pathogenesis of NAFL are expected to be completed. It is anticipated that, through a better understanding of NAFL, more effective treatment protocols can be developed targeting only those patients with NASH that are at the highest risk for progression to cirrhosis and liver failure.     

Metformin in the treatment of non-alcoholic fatty liver disease: safety,efficacy and mechanism

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease etiology worldwide. It encompasses a spectrum ranging from simple steatosis to non-alcoholic steatohepatitis. Although the physiopathology of NAFLD is partly known. Insulin-resistance plays a central role in the development and progression of NAFLD. Several studies have indicated that metformin, as an insulin sensitizer, effectively improves NAFLD and its related metabolic status. Metformin was effective in reducing enzyme levels in the short period, but very limited and controversial information are available on liver histology. Larger randomized controlled trials of sufficient duration using clearly defined histological endpoints are needed to fully assess the efficacy of this drug in modifying the natural history of NAFLD.     

Commonly used animal models of non-alcoholic steatohepatitis

BACKGROUND:Animal models are an essential tool in non-alcoholic steatohepatitis (NASH) studies. Ideally, such models should reflect the etiology, disease progression, and the established pathology of human NASH. To date, no single animal model displays the range of histopathologic and pathophysiologic features associated with human NASH. The currently available models do not or only partially reflect the real picture of human NASH. In particular, insulin resistance and fibrosing steatohepatitis are rarely r...     

Current management of non‐alcoholic steatohepatitis

Non‐alcoholic steatohepatitis (NASH) is the most common cause of liver disease in Western populations, and its prevalence is increasing rapidly. It is part of a multisystem disease affecting other organs such as the kidneys, heart and blood vessels, and is closely associated with the components of the metabolic syndrome. Physicians managing patients with NASH should not only focus on the management of NASH, but also on associated comorbidities in individual patients. The approaches to treatment of NASH include either limiting energy surplus alone, or in combination with targeting of downstream pathways of inflammation and fibrosis. In this mini‐review, we discuss the currently available treatment options for NASH, as well as those in late‐stage clinical trials. We discuss the challenges of managing these patients with a limited number of approved therapies, as well as managing advanced‐stage patients with NASH and cirrhosis. We also discuss the specific management of comorbidities in NASH patients, in particular diabetes, hypertension, dyslipidaemia and cardiovascular diseases. Finally, we present the screening protocols for both hepatocellular carcinoma and extrahepatic malignancies in these patients.     

Non-alcoholic steatohepatitis in type 2 diabetes mellitus

BACKGROUND AND AIMS: Non-alcoholic steatohepatitis (NASH) is commonly associated with type 2 diabetes mellitus (DM). Prevalence of NASH in type 2 DM has not been well studied and there is an epidemic rise in type 2 DM in Asian and Western populations. Its association with chronic liver disease in the form of NASH makes it an important health problem. Hence we have studied its prevalence and correlation of biochemical parameters with histological grades of non-alcoholic fatty liver disease (NAFLD) in otherwise asymptomatic type 2 DM patients. METHODS: One hundred and forty-eight individuals were screened. Forty-eight individuals were excluded due to history of alcohol intake or liver disease as a result of other causes. One hundred non-alcoholic individuals with type 2 DM underwent abdominal ultrasonography (US abdomen). Forty-nine patients had evidence of fatty liver on US abdomen, and 32 of these 49 patients underwent liver biopsy. RESULTS: Four of 32 (12.5%) individuals had steatosis alone. Mild, moderate and severe NASH was present in 21/32 (65.5%), 4/32 (12.5%) and 3/32 (9.35%), respectively. Fibrosis was present in 7/32 (21.8%) patients (four grade 1 and three grade 3). There was no significant difference in body mass index (BMI), transaminase levels, serum cholesterol and triglyceride levels among patients with non-alcoholic fatty liver disease. CONCLUSION: We conclude that the prevalence of NASH is high in type 2 DM patients and liver biopsy is the only investigation to differentiate between non-alcoholic fatty liver and steatohepatitis.     

Roles of adipose restriction and metabolic factors in progression of steatosis to steatohepatitis in obese, diabetic mice

Background and Aims: We previously reported that steatohepatitis develops in obese, hypercholesterolemic, diabetic foz/foz mice fed a high‐fat (HF) diet for 12 months. We now report earlier onset of steatohepatitis in relation to metabolic abnormalities, and clarify the roles of dietary fat and bodily lipid partitioning on steatosis severity, liver injury and inflammatory recruitment in this novel non‐alcoholic steatohepatitis (NASH) model. Methods: Foz/foz (Alms1 mutant) and wild‐type (WT) mice were fed a HF diet or chow, and metabolic characteristics and liver histology were studied at 2, 6, 12 and 24 weeks. Results: After 12 weeks HF‐feeding, foz/foz mice were obese and diabetic with approximately 70% reduction in serum adiponectin. Hepatomegaly developed at this time, corresponding to a plateau in adipose expansion and increased adipose inflammation. Liver histology showed mild inflammation and hepatocyte ballooning as well as steatosis. By 24 weeks, HF‐fed foz/foz mice developed severe steatohepatitis (marked steatosis, alanine aminotransferase elevation, ballooning, inflammation, fibrosis), whereas dietary and genetic controls showed only simple steatosis. While steatosis was associated with hepatic lipogenesis, indicated by increased fatty acid synthase activity, steatohepatitis was associated with significantly higher levels of CD36, indicating active fatty acid uptake, possibly under the influence of peroxisome proliferator‐activated receptor‐γ. Conclusion: In mice genetically predisposed to obesity and diabetes, HF feeding leads to restriction of adipose tissue for accommodation of excess energy, causing lipid partitioning into liver, and transformation of simple steatosis to fibrosing steatohepatitis. The way in which HF feeding ‘saturates’ adipose stores, decreases serum adiponectin and causes hepatic inflammation in steatohepatitis may provide clues to pathogenesis of NASH in metabolic syndrome.     

Circulating vaspin and its relationship with insulin sensitivity,adiponectin, and liver histology in subjects with non-alcoholic steatohepatitis

Abstract

Objective. Non-alcoholic steatohepatitis (NASH) is closely associated with components of metabolic syndrome. Vaspin is a novel adipocytokine that may link obesity, insulin resistance (IR), and type 2 diabetes mellitus. We aimed to investigate circulating vaspin levels in subjects with NASH and also to search for the association of vaspin with IR, adiponectin, and histological findings. Material and methods. A total of 50 male patients with NASH and 30 healthy male controls were enrolled. Vaspin and adiponectin were measured with ELISA method. Insulin sensitivity determined by homeostasis model assessment (HOMA-IR) index. Results. Plasma vaspin levels were higher and adiponectin levels were lower in NASH group compared with controls (p < 0.01 and p < 0.001, respectively). However, in multivariate analysis adjusted for glucose and lipid parameters, and HOMA-IR indexes, the difference in vaspin concentrations was disappeared. Nonetheless, the difference regarding the adiponectin levels remained significant between groups (p = 0.03). Vaspin was negatively correlated with low-density lipoprotein cholesterol (r = -0.32, p = 0.03) in subjects with NASH. Conclusions. This study indicates that circulating vaspin levels are not altered in male subjects with NASH. These results suggest that in the absence of metabolic risk factors, vaspin per se may not be involved in the pathogenesis of NASH.     

成人非酒精性脂肪肝与代谢综合征关系的研究

目的探讨非酒精性脂肪肝(NAFLD)和代谢综合征(MS)的关系。方法对2006年10～12月长沙市某企业3744例20岁以上职工进行问卷调查、体格检查、空腹血糖、血脂、丙氨酸转氨酶、血尿酸检测以及肝脏B超检查。结果(1)NAFLD患病率23.5%,MS患病率22.8%,两病的共患病率12.6%。(2)MS、中心性肥胖、血压升高、空腹血糖升高、高三酰甘油、低高密度脂蛋白胆固醇各组NAFLD患病风险分别是对照组的13.4～22.2倍。(3)以NAFLD取代MS5个组分中的任何一个后,与原诊断定义相比有较高一致性(Kappa值0.53～0.89,P<0.01)。(4)采用多因素Logistic回归分析,调整了性别、年龄和多项代谢成分的影响后,NAFLD与MS独立相关(OR2.342,95%CI:1.825～3.007;P<0.01)。结论该人群中1/5以上患有NAFLD和MS,且NAFLD与MS密切相关;NAFLD可纳入MS的组成成分。     

Inflammatory and fibrotic mechanisms in NAFLD—Implications for new treatment strategies

Non-alcoholic fatty liver disease is comprised of either simple steatosis (non-alcoholic fatty liver) or a more advanced inflammatory and fibrogenic stage (non-alcoholic steatohepatitis [NASH]). NASH affects a growing proportion of the global adult and pediatric population, leading to rising rates of liver fibrosis and hepatocellular carcinoma. NASH is a multifactorial disease that is part of a systemic metabolic disorder. Here, we provide an overview of the metabolic underpinnings of NASH pathogenesis and established drivers of inflammation and fibrosis. Clarification of underlying fibrogenic and inflammatory mechanisms will advance the development of novel treatment strategies as there are no approved therapies at present. We discuss emerging experimental approaches and potential novel investigational strategies derived from animal models including the inflammasome, epigenetic reprogramming, Hippo signaling, Notch signaling, engineered T cells to remove fibrogenic HSCs, and HSC-specific targeting therapies. Recently completed and ongoing clinical trials and antifibrotics are discussed, illuminating the growing expectation that one or more therapies will yield clinical benefit in NASH in the coming years.     

高血压与非酒精性脂肪肝之间关系及其治疗进展

研究发现,高血压、非酒精性脂肪肝与高胰岛素血症、胰岛素抵抗密切相关.现就高血压与非酒精性脂肪肝之间的关系及治疗作一综述.     

The use of current knowledge and non-invasive testing modalities for predicting at-risk non-alcoholic steatohepatitis and assessing fibrosis

There is ongoing recognition of the burden of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH), with fibrosis being the most important histological feature that is associated with progression to cirrhosis and the occurrence of major adverse liver outcomes. Liver biopsy is the gold standard applied to detect NASH and determine the stage of fibrosis, but its use is limited. There is a need for non-invasive testing (NIT) techniques to identify patients considered at-risk NASH (NASH with NAFLD activity score > 4 and ≥ F2 fibrosis). For NAFLD-associated fibrosis, several wet (serological) and dry (imaging) NITs are available and demonstrate a high negative predictive value (NPV) for excluding those with advanced hepatic fibrosis. However, identifying at-risk NASH is more challenging; there is little guidance on how to use available NITs for these purposes, and these NITs are not specifically designed to identify at-risk NASH patients. This review discusses the need for NITs in NAFLD and NASH and provides data to support the use of NITs, focusing on newer methods to non-invasively identify at-risk NASH patients. This review concludes with an algorithm that serves as an example of how NITs can be integrated into care pathways of patients with suspected NAFLD and potential NASH. This algorithm can be used for staging, risk stratification and the effective transition of patients who may benefit from specialty care.     

Placebo-controlled,randomised clinical trial: high-dose resveratrol treatment for non-alcoholic fatty liver disease

Objective “The obesity epidemic” has led to an increase in obesity-related conditions including non-alcoholic fatty liver disease (NAFLD), for which effective treatments are in demand. The polyphenol resveratrol prevents the development of experimental NAFLD through modulation of cellular pathways involved in calorie restriction. We aimed to test the hypothesis that resveratrol alleviates NAFLD in a randomised, clinical trial. Materials and methods A total of 28 overweight patients with transaminasemia and histological NAFLD were randomised 1:1 to placebo or resveratrol 1.5 g daily for 6 months. Twenty-six participants completed the trial and underwent repeated clinical investigation, blood work, MR spectroscopy; and 19 participants agreed to a repeat liver biopsy. Results Resveratrol treatment was generally not superior to placebo in improving plasma markers of liver injury (primary outcome: alanine transaminase, p?=?0.51). Resveratrol-treated patients showed a 3.8% decrease in liver lipid content (p?=?0.03), with no difference between the two treatment arms (p?=?0.38) and no improvement of histological features. Resveratrol treatment was not associated with improvements in insulin sensitivity or markers of the metabolic syndrome, except for a transient decrease in systolic BP. Microarray analysis and qRT-PCR revealed no major changes in expression profile. Also, we report a serious adverse event in a patient who developed fever and bicytopenia. Conclusions In this placebo-controlled, high-dose and long-term study, resveratrol treatment had no consistent therapeutic effect in alleviating clinical or histological NAFLD, though there may be a small ameliorating effect on liver function tests and liver fat accumulation.     

Influence of inducible nitric oxide synthase polymorphisms in Japanese patients with non-alcoholic fatty liver disease

Aim:  Genetic factors as well as environmental factors play an important role in the development of non-alcoholic fatty liver disease (NAFLD). Recently, inducible nitric oxide synthase (iNOS) was significantly higher in the severest form of non-alcoholic steatohepatitis (NASH), and nitric oxide (NO) has been determined to play an important role in the process of fibrosis in NASH. In this study, we investigated iNOS gene polymorphisms for associations with NAFLD.
Methods:  A total of 115 NAFLD patients, consisting of 65 patients with NASH and 50 patients with simple steatosis, in whom a positive diagnosis had been made by liver biopsy, and 435 healthy control subjects, were recruited into this study.
Results:  We investigated 10 single nucleotide polymorphisms (SNP) of the iNOS gene, one of which, rs1060822, had the lowest P -value in the allele frequency model ( P  = 0.00078) with an odds ratio (95% confidence interval) of 0.49 (0.32–0.75). Four SNP, rs2297510, rs2297511, rs2797512 and rs1060822, were significantly associated with NAFLD, even when the most conservative Bonferroni's correction was applied. Linkage disequilibrium analysis revealed that SNP rs1060822 and three other SNP, rs2297510, rs2297511 and rs2797512, were in the same block. We also investigated associations between rs1060822 genotypes and the fibrosis index, and the results of the analysis revealed an additive increase in the fibrosis index and intrahepatic iNOS mRNA expression in the patients with the T allele of rs1060822.
Conclusion:  This is the first study to identify genetic variations in iNOS that may influence the risk of NAFLD and liver fibrosis in NAFLD.     

Impact of Pemafibrate in Patients with Hypertriglyceridemia and Metabolic Dysfunction-associated Fatty Liver Disease Pathologically Diagnosed with Non-alcoholic Steatohepatitis: A Retrospective,Single-arm Study

Objective The therapeutic effect of pemafibrate on metabolic dysfunction-associated fatty liver disease (MAFLD) remains unknown. This retrospective, single-arm study investigated the efficacy and safety of pemafibrate in MAFLD patients with hypertriglyceridemia. Methods A total of 10 patients who received pemafibrate (oral, 0.1 mg, twice a day) at Gunma Saiseikai Maebashi Hospital between September 2018 and September 2019 were included. All patients underwent a liver biopsy, and the disease grade and stage were pathologically assessed based on the FLIP algorithm. Results The median age was 66.0 (53.8-74.8) years old, and 5 patients (50.0%) were men. All patients were diagnosed with non-alcoholic steatohepatitis (NASH). The fasting and non-fasting triglyceride (TG) levels were 175 (149-247) mg/dL and 228 (169-335) mg/dL, respectively. The AST and ALT values at 6 months were significantly lower than at baseline [AST: 28.0 (22.0-33.8) U/L vs. 43.5 (24.0-55.0) U/L, p=0.008, ALT: 23.0 (14.8-26.5) U/L vs. 51.5 (23.0-65.3) U/L, p=0.005, respectively], especially in NASH patients with significant activity and advanced fibrosis (p=0.040 and 0.014, respectively). Fasting TG levels were significantly lower and HDL-C levels significantly higher at 6 months than at baseline (p=0.005 and 0.032, respectively). At six months, FIB-4, the aspartate aminotransferase-to-platelet ratio index, and the macrophage galactose-specific lectin-2 binding protein glycosylation isomer level were significantly improved compared with baseline (p=0.041, 0.005 and 0.005, respectively). Treatment-related adverse events were not observed. Conclusion Pemafibrate treatment may be safe and effective for MAFLD patients with hypertriglyceridemia.     

非酒精性脂肪肝与胰岛素抵抗

目的探讨非酒精性脂肪性肝病（NAFLD）与胰岛素抵抗（IR）的关系。方法NAFLD组52例,非NAFLD组50例,比较两组间BMI、WHR、TC、TG、CRP、HDL-C、LDL-C、ALT、Cr、FBG、FINS和HOMA-IR的差异,并进行Logistic回归分析。结果NAFLD组与非NAFLD组在BMI（26.7±2.3与22.4±2.5,P〈0.01）、WHR（0.94±0.06与0.83±0.05,P〈0.01）、TG（2.4±0.6与1.8±0.6,P〈0.01）、ALT（37.3±8.3与28.1±7.2,P〈0.05）、FBG（6.2±1.4与5.2±0.7,P〈0.01）、FINS（23.6±13.6与8.6±3.5,P〈0.01）、HOMA-IR（6.7±4.7与2.0±1.6,P〈0.01）的差异有统计学意义,Logistic回归分析显示BMI（P〈0.01）、WHR（P〈0.01）、TG（P〈0.01）、ALT（P〈0.05）、HOMA-IR（P〈0.01）是NAFLD的独立影响因素。结论BMI、WHR、TG、ALT、HOMA-IR是NAFLD的独立影响因素。