Metabolic aspects of adult patients with nonalcoholic fatty liver disease

Relevance of combined influence of nutritional and inflammatory status on non-alcoholic fatty liver disease and advanced fibrosis: A mediation analysis of lipid biomarkers

BACKGROUND AND AIM

This study aimed to investigate the relationship between advanced lung cancer inflammation index (ALI) and non-alcoholic fatty liver disease (NAFLD) and advanced liver fibrosis (AF).

METHODS

A total of 5642 individuals from the National Health and Nutrition Examination Survey (NHANES) between 2017 and 2020 were examined. Limited cubic spline regression model, and weighted logistic regression were employed to determine if ALI levels were related to the prevalence of NAFLD and AF. Additionally, a mediating analysis was conducted to investigate the role of lipid biomarkers, such as total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C), in the effects of ALI on the prevalence of NAFLD and AF.

RESULTS

After adjusting for potential confounders, a significant positive association was found between ALI with NAFLD and AF prevalence. Compared with those in ALI Tertile 1, participants in Tertile 3 had higher odds of NAFLD prevalence (odds ratio [OR]: 3.16; 95% confidence interval [CI]: 2.52-3.97) and AF (OR: 3.17; 95% CI: 2.30-4.36). Participants in both Tertile 2 and Tertile 3 had lower odds of developing AF (P for trend = 0.005). Moreover, we discovered a nonlinear association between ALI and NAFLD. An inflection point of 74.25 for NAFLD was identified through a two-segment linear regression model. Moreover, TC and HDL-C levels mediated the association between ALI and NAFLD by 10.2% and 4.2%, respectively (both P < 0.001).

CONCLUSION

Our findings suggest that higher ALI levels are positively associated with an increased prevalence of NAFLD and AF, partly mediated by lipid biomarkers.

The effects of replacing ghee with rapeseed oil on liver steatosis and enzymes, lipid profile, insulin resistance and anthropometric measurements in patients with non-alcoholic fatty liver disease: a randomised controlled clinical trial

Non-alcoholic fatty liver disease (NAFLD), which is a prevalent hepatic condition worldwide, is expected to develop into the leading reason for end-stage fatty liver in the forthcoming decades. Incorporating rapeseed oil into a balanced diet may be beneficial in improving NAFLD. The goal of this trial was to evaluate the impact of substituting ghee with rapeseed oil on primary outcomes such as fatty liver and liver enzymes, as well as on secondary outcomes including glycaemic variables, lipid profile and anthropometric measurements in individuals with NAFLD. Over 12 weeks, 110 patients (seventy men and forty women; BMI (mean) 28·2 (sd 1·6 kg/m2); mean age 42 (sd 9·6) years), who daily consumed ghee, were assigned to the intervention or control group through random allocation. The intervention group was advised to substitute ghee with rapeseed oil in the same amount. The control group continued the consumption of ghee and was instructed to adhere to a healthy diet. Results showed a significant reduction in the steatosis in the intervention group in comparison with the control group (P < 0·001). However, a significant change in the levels of alanine aminotransferase (–14·4 μg/l), γ-glutamyl transferase (–1·8 μg/l), TAG (–39·7 mg/dl), total cholesterol (–17·2 mg/dl), LDL (–7·5 mg/dl), fasting blood glucose (–7·5 mg/dl), insulin (–3·05 mU/l), Homeostatic Model Assessment for Insulin Resistance (–0·9), Quantitative Insulin-Sensitivity Check Index (+0·01), weight (–4·3 kg), BMI (–0·04 kg/m2), waist (–5·6 cm) and waist:height ratio (–0·04) was seen in the intervention group. The consumption of rapeseed oil instead of ghee caused improvements in liver steatosis and enzymes, glycaemic variables and anthropometric measurements among individuals with NAFLD.

Management of non-alcoholic fatty liver disease: Lifestyle changes

In this editorial, we commented on a recently released manuscript by Zeng et al in the World Journal of Gastroenterology. We focused specifically on lifestyle changes in patients with non-alcoholic fatty liver disease (NAFLD). NAFLD is a hepatic manifestation of the metabolic syndrome, which ultimately leads to advanced hepatic fibrosis, cirrhosis, and hepatocellular carcinoma and affects more than 25% of the population globally. Existing therapeutic strategies against NAFLD such as pharmacologic therapies focus on liver protection, anti-inflammation, and regulating disease-related metabolic disorder symptoms. Although several drugs are in late-stage development, potent drugs against the diseases are lacking. Additionally, existing surgical approaches such as bariatric surgery are not routinely used to treat NAFLD. Intervening in patients' unhealthy lifestyles, such as weight loss through dietary changes and exercises to ameliorate patient-associated metabolic disorders and metabolic syndrome, is the first-line treatment for patients with NAFLD. With sufficient intrinsic motivation and adherence, the management of unhealthy lifestyles can reduce the severity of the disease, improve the quality of life, and increase the survival expectancy of patients with NAFLD.

Diet-Induced Gut Dysbiosis and Leaky Gut Syndrome

Chronic gut inflammation promotes the development of metabolic diseases such as obesity. There is growing evidence which suggests that dysbiosis in gut microbiota and metabolites disrupt the integrity of the intestinal barrier and significantly impact the level of inflammation in various tissues, including the liver and adipose tissues. Moreover, dietary sources are connected to the development of leaky gut syndrome through their interaction with the gut microbiota. This review examines the effects of these factors on intestinal microorganisms and the communication pathways between the gut-liver and gut-brain axis. The consumption of diets rich in fats and carbohydrates has been found to weaken the adherence of tight junction proteins in the gastrointestinal tract. Consequently, this allows endotoxins, such as lipopolysaccharides produced by detrimental bacteria, to permeate through portal veins, leading to metabolic endotoxemia and alterations in the gut microbiome composition with reduced production of metabolites, such as short-chain fatty acids. However, the precise correlation between gut microbiota and alternative sweeteners remains uncertain, necessitating further investigation. This study highlights the significance of exploring the impact of diet on gut microbiota and the underlying mechanisms in the gut-liver and gut-brain axis. Nevertheless, limited research on the gut-liver axis poses challenges in comprehending the intricate connections between diet and the gut-brain axis. This underscores the need for comprehensive studies to elucidate the intricate gut-brain mechanisms underlying intestinal health and microbiota.

A study on the treatment effects of Crataegus pinnatifida polysaccharide on non-alcoholic fatty liver in mice by modulating gut microbiota

The objective of this study was to investigate the protective effect of Crataegus pinnatifida polysaccharide (CPP) on non-alcoholic fatty liver disease (NAFLD) induced by a high-fat diet (HFD) in mice. The findings demonstrated that CPP improved free fatty acid (FFA)-induced lipid accumulation in HepG2 cells and effectively reduced liver steatosis and epididymal fat weight in NAFLD mice, as well as decreased serum levels of TG, TC, AST, ALT, and LDL-C. Furthermore, CPP exhibited inhibitory effects on the expression of fatty acid synthesis genes FASN and ACC while activating the expression of fatty acid oxidation genes CPT1A and PPARα. Additionally, CPP reversed disturbances in intestinal microbiota composition caused by HFD consumption. CPP decreased the firmicutes/Bacteroidetes ratio, increased Akkermansia abundance, and elevated levels of total short-chain fatty acid (SCFA) content specifically butyric acid and acetic acid. Our results concluded that CPP may intervene in the development of NAFLD by regulating of intes-tinal microbiota imbalance and SCFAs production. Our study highlights that CPP has a potential to modulate lipid-related pathways via alterations to gut microbiome composition thereby ex-erting inhibitory effects on obesity and NAFLD development.

Influence of Sugar-Sweetened Beverages Intake on Sarcopenic Obesity, Visceral Obesity, and Sarcopenia in Lebanese Patients with MASLD: A Case-Control Study

Chronic liver diseases are a major global health concern.

AIMS

this study investigated the links between medical, clinical, anthropometric, and dietary factors with dysfunction-associated steatotic liver disease (MASLD) in the Lebanese population using a case-control approach to uncover factors influencing visceral obesity, sarcopenia, and sarcopenic obesity.

METHODS AND MATERIALS

a total of 120 participants (20-70 years old) were divided into case and control groups based on liver disease diagnosis. Patient information was gathered through a questionnaire encompassing demographics, medical history, and beverage consumption. Anthropometric and body composition data were collected in a clinical setting.

RESULTS

our findings indicated a clear association between the presence of MASLD and obesity, hypertension, and diabetes. The positive association with higher body mass index and all three conditions remained consistent even when data was stratified by case and control groups. A greater proportion of MASLD patients exhibited sarcopenic obesity. Furthermore, MASLD cases showed higher consumption of sugary beverages and a reduced intake of milk and water in their diets.

CONCLUSIONS

this study shed light on the health attributes and diets of the Lebanese population with liver diseases and suggested more research in this area and in a more ethnically diverse population.

Phase 2, open-label, rollover study of cenicriviroc for liver fibrosis associated with metabolic dysfunction-associated steatohepatitis

BACKGROUND

Cenicriviroc (CVC) is a novel, orally administered antagonist of chemokine receptor types 2/5 that has demonstrated antifibrotic activity in a phase 2b study of patients with NASH. This phase 2, open-label, rollover study investigated the long-term safety and tolerability of CVC in patients with NASH and stage 0-4 liver fibrosis.

METHODS

Eligible patients who completed the phase 2 CENTAUR study or reached a predefined endpoint in the phase 3 AURORA study were rolled over and received open-label CVC 150 mg once daily. Safety assessments were conducted at the start of the study, and patients were seen in the clinic every 3 months until the study sponsor terminated CVC development. Safety endpoints included treatment-emergent adverse events (TEAEs), treatment-related TEAEs, adverse event severity, and clinical laboratory assessments.

RESULTS

A total of 167 patients were enrolled, with a median treatment duration of 33.6 months. Before study termination, 36 patients (21.6%) prematurely discontinued the study. Treatment-related TEAEs were reported in 28 patients (16.8%). The most common treatment-related TEAEs were 4 cases of diarrhea (2.4%) and 2 cases each (1.2%) of abdominal pain, nausea, alanine aminotransferase increased, aspartate aminotransferase increased, hypertriglyceridemia, myalgia, pruritus, and rash. The majority of these treatment-related events were mild in intensity, and none were life-threatening. There were no clinically meaningful changes in hepatic function, chemistry, or liver parameters from baseline to the end of the study.

CONCLUSIONS

In this rollover study, CVC 150 mg once daily was well tolerated in patients with NASH and stage 0-4 liver fibrosis. No new safety signals were reported, and these data further support the safety and tolerability of CVC.

Association between cataract and fatty liver diseases from a nationwide cross-sectional study in South Korea

This study examined the link between fatty liver disease (FLD) and cataracts, as previous research has suggested that FLD may contribute to metabolic syndrome, systemic inflammation, and potentially cataracts. We studied a nationwide cross-sectional cohort of the Fifth Korean National Health and Nutrition Examination Survey 2010-2011. FLD was defined as nonalcoholic FLD (NAFLD) and metabolic dysfunction-associated FLD (MAFLD). Multinomial logistic regression was utilized to investigate the relationship between cataracts and FLD after adjustment for potential confounders. Participants with cataracts had higher liver fibrosis scores, including the NAFLD fibrosis score (NFS; P < 0.001), fibrosis-4 index (FIB4; P < 0.001), and fatty liver index (FLI; P = 0.001). NAFLD was not associated with a higher odds ratio (OR) for cataracts in the fully adjusted model (OR = 1.23, P = 0.058). MAFLD was significantly associated with a higher OR (OR = 1.34, P = 0.006). After adjusting for all factors, the severity of FLD was linked to an increased risk of cataracts, with significant linear trends (P values for linear trends of NFS, FIB4, and FLI < 0.05). After adjusting for well-known cataract risk factors, MAFLD was significantly associated with cataracts. Our analysis suggests that FLD may serve as an independent risk factor for cataracts.

Effects of lacto-ovo-vegetarian diet vs. standard-weight-loss diet on obese and overweight adults with non-alcoholic fatty liver disease: a randomised clinical trial

The aim of the study was to compare the effects of a lacto-ovo-vegetarian diet (LOV-D) vs. a standard weight-loss diet (SWL-D) on obese/overweight adults with NAFLD. Present randomised clinical trial recruited 75 overweight/obese adults with NAFLD, who were randomly assigned into LOV-D and SWL-D groups for 3 months. The LOV-D was designed based on eliminating meat, poultry, and fish; while including dairy products and eggs. The SWL-D was planned according to the standard food pyramid, which was free in all sources of food. Adherence to LOV-D significantly outperformed SWL-D in reducing levels of alanine aminotransferase (ALT), body weight, waist circumference, BMI, fasting blood sugar, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), triacylglycerol (TG), cholesterol, low-density lipoprotein cholesterol (LDL-C), and systolic blood pressure (SBP). Furthermore, ultrasonography revealed a higher alleviation in NAFLD grade among LOV-D, compared with SWL-D. This study suggests that adherence to LOV-D for 3 months has beneficial effects on NAFLD improvement, anthropometric measures, glycaemic-related markers, and lipid profiles.

Mediterranean diet affects the metabolic outcome of metabolic dysfunction-associated fatty liver disease

The prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) is on the rise globally. It is currently one of the most prevalent liver diseases and one of the world's important public health problems. At present, there is no consensus on a pharmacological treatment for MAFLD. By contrast, lifestyle interventions based on exercise and a balanced diet are considered to be the cornerstone of MAFLD management. Mediterranean diet (MD) have a large content of polyphenols, polyunsaturated fatty acids, oleic acid, carotenoids and fiber, which carry out antioxidant, anti-inflammatory and antibacterial benefits. It has been considered to reduce the incidence rate of cardiovascular disease and type 2 diabetes. The purpose of this narrative review is therefore to summarize and analyze the evidence for the effect of MD on metabolic outcomes in MAFLD patients.

Towards an adiposity-related disease framework for the diagnosis and management of obesities

Obesity is a complex disease that relapses frequently and associates with multiple complications that comprise a worldwide health priority because of its rising prevalence and association with numerous complications, including metabolic disorders, mechanic pathologies, and cancer, among others. Noteworthy, excess adiposity is accompanied by chronic inflammation, oxidative stress, insulin resistance, and subsequent organ dysfunction. This dysfunctional adipose tissue is initially stored in the visceral depot, overflowing subsequently to produce lipotoxicity in ectopic depots like liver, heart, muscle, and pancreas, among others. People living with obesity need a diagnostic approach that considers an exhaustive pathophysiology and complications assessment. Thus, it is essential to warrant a holistic diagnosis and management that guarantees an adequate health status, and quality of life. The present review summarizes the different complications associated with obesity, at the same time, we aim to fostering a novel framework that enhances a patient-centered approach to obesity management in the precision medicine era.

Effect of spironolactone on pharmacological treatment of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) was recently renamed to metabolic (dysfunction)-associated fatty liver disease (MAFLD) to better characterize its pathogenic origin. NAFLD represents, at least in western societies, a potential epidemic with raising prevalence. Its multifactorial pathogenesis is partially unraveled and till now there is no approved pharmacotherapy for NAFLD. A plethora of various choices are investigated in clinical trials, targeting an arsenal of different pathways and molecules. Since the mineralocorticoid receptor (MR) and renin-angiotensin-aldosterone system (RAAS) appear to be implicated in NAFLD, within this concise review, we focus on a rather classical and inexpensive pharmacological agent, spironolactone. We present the current lines of evidence of MR and RAAS-related preclinical models and human trials reporting an association with NAFLD. In conclusion, evidence about spironolactone of RAAS is commented, as potential future pharmacological management of NAFLD.

The Replacement of Only One Portion of Starchy Carbohydrates with Green Leafy Vegetables Regresses Mid and Advanced Stages of NAFLD: Results from a Prospective Pilot Study

The gold standard treatment for NAFLD is weight loss and lifestyle interventions, which require a diet enriched in fiber and reduced in sugars and saturated fats. Fibres may be advantageous for NAFLD patients since they reduce and slow the absorption of carbohydrates, lipids, and proteins, lowering the energy density of the meal and increasing their sense of satiety. Furthermore, the polyphenol content and other bioactive compounds of vegetables have antioxidant and anti-inflammatory properties preventing disease progression. The aim of this study is to ascertain the effects of a diet enriched by green leafy vegetables and with a moderate restriction of carbohydrate intake in patients with NAFLD over a three month period. Among the forty patients screened, twenty four patients completed the clinical trial consisting of swapping one portion of carbohydrate-rich food for one portion of green leafy vegetables, and liver and metabolic markers of NAFLD were evaluated. All patients underwent routine blood tests, anthropometric measurements, bioelectrical impedance analysis, fibroscan, and fatty liver index (FLI) evaluation before and at the end of the study. The population under study (n = 24) had a median age of 47.5 (41.5-52.5) years and included mainly women (70.8%). We found that FLI, which is used to predict fatty liver (73 (33-89) vs. 85 (54-95), p < 0.0001) and the FAST score, which is a fibroscan-derived parameter identifying patients at risk of progressive NASH (0.03 (0.02-0.09) vs. 0.05 (0.02-0.15), p = 0.007), were both improved after changes in diet. The BMI (33.3 (28.6-37.3) vs. 35.3 (31.2-39.0), p < 0.0001), WC (106.5 (95.0-112.5) vs. 110.0 (103.0-124.0), p < 0.0001), neck circumference (38.0 (35.0-41.5) vs. 39.5 (38.0-42.5), p < 0.0001), fat mass (32.3 (23.4-40.7) vs. 37.9 (27.7-43.5), p < 0.0001), and extracellular water (17.3 (15.2-20.8) vs. 18.3 (15.9-22.7), p = 0.03) were also all significantly lower after three months of diet. Metabolic parameters linked to NAFLD decreased: HbA1c (36.0 (33.5-39.0) vs. 38.0 (34.0-40.5), p = 0.01), triglycerides (72 (62-90) vs. 90 (64-132), p = 0.03), and the liver markers AST (17 (14-19) vs. 18 (15-27), p = 0.01) and γGT (16 (13-20) vs. 16 (14-27), p = 0.02). In conclusion, replacing only one portion of starchy carbohydrates with one portion of vegetables for a three month period is sufficient to regress, at least in part, both mid and advanced stages of NAFLD. This moderate adjustment of lifestyle habits is easily achievable.

Gypenosides ameliorate high-fat diet-induced nonalcoholic fatty liver disease in mice by regulating lipid metabolism

Gypenosides (GP), extracted from the traditional Chinese herb Gynostemma pentaphyllum (Thunb.) Makino, have been used to treat metabolic disorders, including lipid metabolism disorders and diabetes. Although recent studies have confirmed their beneficial effects in nonalcoholic fatty liver disease (NAFLD), the underlying therapeutic mechanism remains unclear. In this study, we explored the protective mechanism of GP against NAFLD in mice and provided new insights into the prevention and treatment of NAFLD. Male C57BL6/J mice were divided into three experimental groups: normal diet, high-fat diet (HFD), and GP groups. The mice were fed an HFD for 16 weeks to establish an NAFLD model and then treated with GP for 22 weeks. The transcriptome and proteome of the mice livers were profiled using RNA sequencing and high-resolution mass spectrometry, respectively. The results showed that GP decreased serum lipid levels, liver index, and liver fat accumulation in mice. Principal component and heatmap analyses indicated that GP significantly modulated the changes in the expression of genes associated with HFD-induced NAFLD. The 164 differentially expressed genes recovered using GP were enriched in fatty acid and steroid metabolism pathways. Further results showed that GP reduced fatty acid synthesis by downregulating the expression of Srebf1, Fasn, Acss2, Acly, Acaca, Fads1, and Elovl6; modulated glycerolipid metabolism by inducing the expression of Mgll; promoted fatty acid transportation and degradation by inducing the expression of Slc27a1, Cpt1a, and Ehhadh; and reduced hepatic cholesterol synthesis by downregulating the expression of Tm7sf2, Ebp, Sc5d, Lss, Fdft1, Cyp51, Nsdhl, Pmvk, Mvd, Fdps, and Dhcr7. The proteomic data further indicated that GP decreased the protein expression levels of ACACA, ACLY, ACSS2, TM7SF2, EBP, FDFT1, NSDHL, PMVK, MVD, FDPS, and DHCR7 and increased those of MGLL, SLC27A1, and EHHADH. In conclusion, GP can regulate the key genes involved in hepatic lipid metabolism in NAFLD mice, providing initial evidence for the mechanisms underlying the therapeutic effect of GP in NAFLD.

Reactive Oxygen Species in the Aorta and Perivascular Adipose Tissue Precedes Endothelial Dysfunction in the Aorta of Mice with a High-Fat High-Sucrose Diet and Additional Factors

Metabolic syndrome (Mets) is the major contributor to the onset of metabolic complications, such as hypertension, type 2 diabetes mellitus (DM), dyslipidemia, and non-alcoholic fatty liver disease, resulting in cardiovascular diseases. C57BL/6 mice on a high-fat and high-sucrose diet (HFHSD) are a well-established model of Mets but have minor endothelial dysfunction in isolated aortas without perivascular adipose tissue (PVAT). The purpose of this study was to evaluate the effects of additional factors such as DM, dyslipidemia, and steatohepatitis on endothelial dysfunction in aortas without PVAT. Here, we employed eight-week-old male C57BL/6 mice fed with a normal diet (ND), HFHSD, steatohepatitis choline-deficient HFHSD (HFHSD-SH), and HFHSD containing 1% cholesterol and 0.1% deoxycholic acid (HFHSD-Chol) for 16 weeks. At week 20, some HFHSD-fed mice were treated with streptozocin to develop diabetes (HFHSD-DM). In PVAT-free aortas, the endothelial-dependent relaxation (EDR) did not differ between ND and HFHSD (p = 0.25), but in aortas with PVAT, the EDR of HFHSD-fed mice was impaired compared with ND-fed mice (p = 0.005). HFHSD-DM, HFHSD-SH, and HFHSD-Chol impaired the EDR in aortas without PVAT (p < 0.001, p = 0.019, and p = 0.009 vs. ND, respectively). Furthermore, tempol rescued the EDR in those models. In the Mets model, the EDR is compromised by PVAT, but with the addition of DM, dyslipidemia, and SH, the vessels themselves may result in impaired EDR.

Proteomic analysis of the effect of high-fat-diet and voluntary physical activity on mouse liver

Nonalcoholic fatty liver disease (NALFD), characterized by an abnormal accumulation of triglycerides in hepatocytes, is closely linked to insulin resistance, metabolic syndrome, and changes in lipogenesis in the liver. The accumulation of hepatic lipids can lead to a range of pathologies from mild steatosis to severe cirrhosis. Endurance exercise is known to ameliorate the adverse health effects of NAFLD. Therefore, we aimed to investigate the effect of voluntary wheel running (VWR) on the metabolic changes in the livers of high-fat diet (HFD)-induced NAFLD mice and used LC-MS/MS (Liquid chromatography–mass spectrometry) to determine whether the tested intervention affected the protein expression profiles of the mouse livers. Male C57BL/6 mice were randomly divided into three groups: control (CON), high-fat diet sedentary group (HFD), high-fat diet VWR group (HFX). HFX group performed voluntary wheel running into individually cages, given a high-fat diet for 12 weeks. Food consumption, body weight, and running distance were measured every week. Using 2D (2-dimensional)-gel electrophoresis, we detected and quantitatively analyzed the protein expression with >2.0-fold change in the livers of HFD-fed mice, HFD-fed exercise (HFX) mice, and chow-fed mice. Body weight was significantly increased in HFD compared to CON (P < 0.05). The 2D-gel electrophoresis analysis indicated that there was a difference between CON and HFD groups, showing 31 increased and 27 decreased spots in the total 302 paired spots in the HFD group compared to CON. The analysis showed 43 increased and 17 decreased spots in the total 258 spots in the HFX group compared to CON. Moreover, 12 weeks of VWR showed an increase of 35 and a decrease of 8 spots in a total of 264 paired spots between HFD and HFX. LC-MS/MS of HFD group revealed that proteins involved in ketogenesis, lipid metabolism, and the metabolism of drugs and xenobiotics were upregulated, whereas detoxifying proteins, mitochondrial precursors, transport proteins, proteasomes, and proteins involved in amino acid metabolism were downregulated. On the other hand, VWR counteracted the protein expression profile of HFD-fed mice by upregulating molecular chaperones, gluconeogenesis-, detoxification-, proteasome-, and energy metabolism-related proteins. This study provided a molecular understanding of the HFD- and exercise-induced protein marker expression and presented the beneficial effects of exercise during pathophysiological conditions.

Effect of Medicinal Plants and Natural Products on Liver Enzymes in Non-alcoholic Fatty Liver Patients in Iran: A Systematic Review and Meta-Analysis

Background

Nonalcoholic fatty liver is the most common chronic liver disease. Regarding the side effects of synthetic medicines and the variety of natural products in Iran climate, the present study aimed to investigate the effect of medicinal plants and natural products on liver enzymes in patients with non-alcoholic fatty liver disease in Iran using meta-analysis.

Methods

To extract the intended studies, internal and external databases, including SID, Magiran, IranDoc, PubMed, Scopus, Web of Science, Embase, Cochrane, and Clinical Trial Registration System of Clinical trial.gov, the ISRCTN system, as well as Clinical Trial Registration System affiliated to the World Health Organization were searched. The obtained data were analyzed in STATA.14 software. A P value less than 0.05 was considered statistically significant.

Results

A total of 44 rstudies were reviewed with a sample size of 1298 participant; they were published in the period from 2009 to 2018, silymarin had the highest effect on the reduction of AST (SMD = -2.68), cinnamon excreted the most profound effect on ALT (SMD = -2.69). In addition, cinnamon had the highest effect on gamma-glutamyl transferase (GGT) (SMD:-3.17), and curcumin had the highest effect on alkaline phosphatase (ALP) (SMD = -1.88). In the lipid profile, the effect of medicinal herbs and natural products on lowering total cholesterol and LDL was statistically significant. In the glycemic profile, the effect of medicinal plants and natural products on the reduction of fasting blood sugar, insulin, and hemoglobin A1c levels was statistically significant.

Conclusions

As evidenced by the obtained results, the highest effect of using natural products was observed in the reduction of GGT, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels, respectively; nonetheless, the effect of natural products on ALP reduction was not statistically significant.

Relation of Dietary Patterns and Nutritional Profile to Hepatic Fibrosis in a Sample of Lebanese Non-Alcoholic Fatty Liver Disease Patients

Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver injury worldwide. NAFLD can evolve into non-alcoholic steatohepatitis (NASH) with or without fibrosis. The objectives of this study were to determine the nutritional profile and dietary patterns of NAFLD Lebanese patients and to report the type of diet-related to the presence of hepatic fibrosis. We hypothesized that the traditional pattern was related to a low risk of fibrosis. This cross-sectional study included 320 eligible Lebanese NAFLD patients. Three dietary patterns were identified: the Traditional diet, the High Fruit diet, and the Westernized diet. Multivariate analysis showed a significant relationship between high adherence to the traditional diet and absence of hepatic fibrosis with a decreased risk of 82%, p = 0.031 after adjusting for its covariables. Fruits were absent from this dietary pattern. Although our results pointed to a possible relationship between fibrosis in NAFLD patients and fruit intake, experimental studies are needed to show whether this is a causal relationship. However, the results obtained in this study may contribute to the planning of dietary interventions and recommendations and enable a better follow-up for NAFLD patients with fibrosis.

Sex influences the association between appendicular skeletal muscle mass to visceral fat area ratio and non-alcoholic steatohepatitis in patients with biopsy-proven non-alcoholic fatty liver disease

Sarcopenic obesity is regarded as a risk factor for the progression and development of non-alcoholic fatty liver disease (NAFLD). Since male sex is a risk factor for NAFLD and skeletal muscle mass markedly varies between the sexes, we examined whether sex influences the association between appendicular skeletal muscle mass to visceral fat area ratio (SVR), that is, an index of skeletal muscle mass combined with abdominal obesity, and the histological severity of NAFLD. The SVR was measured by bioelectrical impedance in a cohort of 613 (M/F = 443/170) Chinese middle-aged individuals with biopsy-proven NAFLD. Multivariable logistic regression and subgroup analyses were used to test the association between SVR and the severity of NAFLD (i.e. non-alcoholic steatohepatitis (NASH) or NASH with the presence of any stage of liver fibrosis). NASH was identified by a NAFLD activity score ≥5, with a minimum score of 1 for each of its categories. The presence of fibrosis was classified as having a histological stage ≥1. The SVR was inversely associated with NASH in men (adjusted OR 0·62; 95 % CI 0·42, 0·92, P = 0·017 for NASH, adjusted OR 0·65; 95 % CI 0·43, 0·99, P = 0·043 for NASH with the presence of fibrosis), but not in women (1·47 (95 % CI 0·76, 2·83), P = 0·25 for NASH, and 1·45 (95 % CI 0·74, 2·83), P = 0·28 for NASH with the presence of fibrosis). There was a significant interaction for sex and SVR (P_interaction = 0·017 for NASH and P_interaction = 0·033 for NASH with the presence of fibrosis). Our findings show that lower skeletal muscle mass combined with abdominal obesity is strongly associated with the presence of NASH only in men.

Vitamin D3 intake as modulator for the early biomarkers of myocardial tissue injury in diabetic hyperlipidaemic rats

CONTEXT

Myocardial cell death occurs within hours following the onset of myocardial ischaemia and its chief cause is atherosclerosis. There is a link between vitamin D3 deficiency and many cardiovascular risk factors.

OBJECTIVE

This study compared the effect of vitamin D3 on early biomarkers of myocardial injury, to that of atorvastatin.

METHODS

Diabetic hyperlipidaemia was induced in Wistar rats, which were divided into 3 groups: diabetic hyperlipidaemic control, diabetic hyperlipidaemic rats treated with atorvastatin and diabetic hyperlipidaemic rats treated with vitamin D3. Blood glucose, glycated haemoglobin and lipid profile were evaluated. Markers of myocardial injury were examined including cardiac troponin, heart fatty acid binding protein (HFABP) and C-terminal pro-endothelin-1 (CT-pro-ET-1).

RESULTS

Vitamin D3 and atorvastatin intake improved lipid profile and glucose homeostasis, and reduced levels of predictive biomarkers of myocardial injury.

CONCLUSION

Vitamin D3 can be used in a suitable dose as a safe and protective candidate against myocardial injury.

Weekend catch-up sleep is associated with the alleviation of non-alcoholic fatty liver disease

INTRODUCTION AND OBJECTIVES

Recently, interest in the relationship between weekend catch-up sleep (WCUS) and chronic diseases is increasing. We aimed to study the correlation between sleep duration and non-alcoholic fatty liver disease (NAFLD), an emerging metabolic disease.

MATERIALS AND METHODS

Data on sleep duration from the Korea National Health and Nutrition Examination Survey was recorded. The subjects were divided into three groups according to the duration of WCUS: Group 1, those who slept for less than 7 hours in a week; Group 2, those who slept for less than 7 hours on weekdays but more than 7 hours on weekends (those with WCUS pattern); and Group 3, those who slept for more than 7 hours in a week. Multivariate logistic regression analysis was used to analyze the correlation between sleep duration and NAFLD.

RESULTS

A mean sleep time of 7 hours or more showed a significant negative relationship with NAFLD (odds ratio [OR]: 0.84, 95% confidence interval [CI]: 0.79-0.89 in all; OR 0.91, 95%CI 0.84-0.99 in males; OR 0.86, 95%CI 0.79-0.94 in females). Groups 2 and 3 showed significant negative relationships with NAFLD when Group 1 was used as a reference (Group 2; OR: 0.80, 95%CI: 0.70-0.92, Group 3; OR: 0.73, 95%CI: 0.66-0.82). WCUS showed similar correlations with NAFLD, regardless of sex.

CONCLUSIONS

WCUS and sleep duration are significantly associated with NAFLD. A prospective cohort study is needed to prove the causal effects.

De novo lipogenesis in non-alcoholic fatty liver disease: Quantification with stable isotope tracers

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is characterized as an abnormal accumulation of triglyceride in hepatocytes. Hepatic de novo lipogenesis may play an important role in the accumulation of lipids in the liver during NAFLD. Due to the importance of lipid biosynthetic fluxes in NAFLD and T2D, tracer methodologies have been developed for their study and quantification. Here, we address novel approaches to measure and quantify DNL using stable isotope tracers. Deuterated water is a widely used tracer for quantifying DNL rates in both animal models and humans. Enrichment of lipid hydrogens from ² H2O can be resolved and quantified by ² H NMR and MS spectroscopy of isolated lipids. NMR provides a much higher level of positional enrichment information compared with MS which yields a more detailed picture of lipid biosynthetic. It can also be used to quantify low levels of lipid ¹³ C enrichment from a second tracer such as [U-¹³ C]sugar with minimal interference of one tracer with the other.

CONCLUSIONS

Despite the clear association between elevated DNL activity and increased hepatic triglyceride levels, implementation of non-destructive and novel methods to quantify DNL and its contribution to NAFLD are also of huge interest.

Inflammation is associated with impairment of oxidative status, carbohydrate and lipid metabolism in type 2 diabetes complicated by non-alcoholic fatty liver disease

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is accompanied by inflammation and impairment of the lipid metabolism. In addition, NAFLD is one of the major complications of type 2 diabetes associated with oxidative stress. Based on this, we evaluated the tumour necrosis factor alpha (TNF-α), nuclear factor κB (NF-κB), oxidative status rates, and analysed its correlation with carbohydrate and lipid metabolism in patients with NAFLD and type 2 diabetes.

METHODS

A case-control study included 63 participants with NAFLD developing in patients with type 2 diabetes, and 65 healthy volunteers with a normal complete blood count and blood biochemical profile. The following parameters and states were assessed during the study: glycaemia, insulin resistance, lipid levels, liver tests, intensity of free radical induced oxidation, antioxidant enzymes, TNF-α and NF-κB level.

RESULTS

Free radical induced oxidation was significantly elevated (p<0.001), total antioxidant activity was significantly decreased (p<0.001) and associated with insulin resistance (p=0.019) and lipid metabolism shifts (p<0.05) in patients with NAFLD and type 2 diabetes. Such patients had showed impaired functioning of antioxidant system (p<0.001), inhibition of NADPH-generating enzymes activity (p<0.001), increased levels of TNF-α (p<0.001) and NF-κB (p=0.019) correlated with the severity of hyperglycaemia (p<0.05), concentration of reduced glutathione (p=0.005) and total cholesterol (p=0.016).

CONCLUSIONS

The increase of free radical induced oxidation, TNF-α and NF-κB levels, and depletion of the antioxidant system seems to be the key factors of the development of NAFLD in patients with type 2 diabetes.

The Association Between Vitamin D and Type 2 Diabetes Mellitus Complicated with Non-Alcoholic Fatty Liver Disease: An Observational Cross-Sectional Study

OBJECTIVE

To investigate the association between vitamin D deficiency and NAFLD risk in patients with type 2 diabetes mellitus (T2DM).

METHODS

Overall, 434 patients with T2DM admitted to Hebei General Hospital from January 2019 to December 2019 were selected as the study subjects. According to abdominal ultrasound findings, patients were divided into the NAFLD group and the non-NAFLD group. Participants were divided into two study groups according to the 25-hydroxyvitamin D [25(OH)D] level. 25(OH)D deficiency was defined if 25(OH)D vitamin levels were <20 ng/mL. Chi-square test and one-way analysis of variance were used to compare groups. The relationship between 25(OH)D and NAFLD risk was analyzed using correlation and regression analyses. Furthermore, subgroup analyses were performed to verify the robustness of the results.

RESULTS

The 25(OH)D level in patients with T2DM complicated by NAFLD was significantly lower than in patients with T2DM only. Vitamin D deficiency was highly prevalent among T2DM patients with NAFLD. This study suggested that vitamin D deficiency was an independent factor for developing NAFLD in patients with T2DM. T2DM patients with vitamin D deficiency had 2.045 times higher risk of developing NAFLD than those without vitamin D deficiency. Vitamin D deficiency was associated with high NAFLD preference in T2DM patients with BMI >23kg/m², but not those with BMI ≤23kg/m². The significant correlation between vitamin D deficiency and NAFLD was found in participants with BMI >23kg/m², age ≤65 years, without hypertension, TG <1.7mmol/l, HDL ≥1 mmol/l in men, ≥1.3 mmol/l in women, HBA1C ≤7%, or females.

CONCLUSION

This study suggests that T2DM people with BMI >23kg/m² were more susceptible to NAFLD by vitamin D deficiency and that it is necessary to maintain optimal serum vitamin D levels in this population.

Effect of Nutrition Education in NAFLD Patients Undergoing Simultaneous Hyperlipidemia Pharmacotherapy: A Randomized Controlled Trial

BACKGROUND

Patients with non-alcoholic fatty liver disease (NAFLD) have a high prevalence of combined hyperlipidemia. The importance of nutritional education is well-known in NAFLD, but the impact of medical nutrition therapy (MNT) is unclear in patients with NAFLD with hyperlipidemia. The purpose of this study is to investigate the effect of MNT on the improvement of steatohepatitis in patients with NAFLD taking antihyperlipidemic medications.

METHODS

Nondiabetic patients with dyslipidemia were prospectively randomized (1:1) either to the MNT group or the control group with standard advice for 48 weeks with simultaneous statin/ezetimibe combination pharmacotherapy at three tertiary centers in Korea.

RESULTS

Sixty-six patients were enrolled. Among them, 18 patients dropped out and, overall, 48 patients (MNT group 27, control group 21) were prospectively analyzed in the study. The serum ALT level at 48 weeks between the two groups was not significantly different (66.6 ± 37.7 IU/L vs. 57.4 ± 36.7 IU/L, p = 0.40). Serum liver enzymes, controlled attenuation parameter and fibrosis-4 index were significantly improved within the MNT group after 48 weeks compared to baseline. There was no significant difference between the two groups other than the NAFLD fibrosis score (p = 0.017).

CONCLUSIONS

Although there were no significant differences between the two groups in terms of steatosis, metabolic and fibrosis surrogate indicators after 48 weeks, MNT groups showed significant improvement within patient analysis over time. Future studies with a larger number of subjects and a longer study period regarding the effect of MNT are warranted.

Dietary patterns and risk of non-alcoholic fatty liver disease in adults: A prospective cohort study

BACKGROUND AND AIMS

Prospective cohort studies linking dietary patterns and non-alcoholic fatty liver disease (NAFLD) are limited, especially in Asian populations. This study aimed to prospectively investigate the association between dietary patterns and risk of NAFLD in a general Chinese adult population.

METHODS

This study included a total of 17,360 participants free from NAFLD at baseline. Dietary patterns at baseline were identified with factor analysis based on responses to a validated 100-item food frequency questionnaire. NAFLD was diagnosed by abdominal ultrasound after excluding other causes related to chronic liver disease. Cox proportional regression models were used to assess the association between dietary patterns and risk of NAFLD.

RESULTS

During a median follow-up of 4.2 years, 4034 NAFLD cases were documented. Three main dietary patterns were extracted: sugar rich dietary pattern, vegetable rich dietary pattern, and animal food dietary pattern. After adjusting for age, sex, body mass index, smoking, alcohol, education, occupation, income, physical activity, total energy intake, personal and family history of disease, depressive symptoms, dietary supplement use, inflammation markers, and each other dietary pattern score, comparing the highest with the lowest quartiles of dietary pattern scores, the multivariable hazard ratios (95% confidence interval) of NAFLD were 1.11 (1.01, 1.23) for sugar rich dietary pattern, 0.96 (0.86, 1.07) for vegetable rich dietary pattern, and 1.22 (1.10, 1.36) for animal food dietary pattern. Further adjustment for waist circumference instead of body mass index provided similar results.

CONCLUSION

Dietary patterns rich in animal foods or sugar were associated with a higher risk of NAFLD among Chinese adults, whereas a vegetable rich dietary pattern was not associated.

Impact of dietary compositions and patterns on the prevalence of nonalcoholic fatty liver disease in Japanese men: a cross-sectional study

BACKGROUND

This study aimed to examine the impact of dietary compositions and patterns on nonalcoholic fatty liver disease (NAFLD) morbidity in Japanese men.

METHODS

We conducted a cross-sectional study of 281 individuals who underwent comprehensive medical examinations during health screening. Dietary intake was assessed using a semi-quantitative food frequency questionnaire, and factor analysis was performed to detect dietary patterns. NAFLD was diagnosed by the presence of fatty liver on abdominal ultrasonography in nondrinkers (< 30 g/day), and patients were categorized into control (n = 192) and NAFLD groups (n = 89).

RESULTS

Compared with the control group, the NAFLD group consumed fewer mushrooms. Three dietary patterns were identified, namely, a healthy pattern, a western pattern, and a snack pattern. The score of healthy pattern was negatively correlated with the risk of NAFLD. Compared with the lowest tertile of the healthy pattern, the middle tertile was associated with a lower risk of NAFLD after adjusting for age, physical activity, and smoking (odds ratio: 0.47, 95% confidence interval: 0.25-0.91). After further adjustments for body mass index, the middle tertile was associated with a lower risk of NAFLD (odds ratio: 0.46, 95% confidence interval: 0.23-0.92).

CONCLUSIONS

A healthy dietary pattern comprising frequent intake of seaweeds, vegetables, mushrooms, pulses, and potatoes and starches was associated with a lower risk of NAFLD in Japanese men. In our opinion, this healthy pattern closely resembles the Japanese Washoku diet, indicating that adherence to Washoku may help prevent NAFLD.

CYP2E1 in Alcoholic and Non-Alcoholic Liver Injury. Roles of ROS, Reactive Intermediates and Lipid Overload

CYP2E1 is one of the fifty-seven cytochrome P450 genes in the human genome and is highly conserved. CYP2E1 is a unique P450 enzyme because its heme iron is constitutively in the high spin state, allowing direct reduction of, e.g., dioxygen, causing the formation of a variety of reactive oxygen species and reduction of xenobiotics to toxic products. The CYP2E1 enzyme has been the focus of scientific interest due to (i) its important endogenous function in liver homeostasis, (ii) its ability to activate procarcinogens and to convert certain drugs, e.g., paracetamol and anesthetics, to cytotoxic end products, (iii) its unique ability to effectively reduce dioxygen to radical species causing liver injury, (iv) its capability to reduce compounds, often generating radical intermediates of direct toxic or indirect immunotoxic properties and (v) its contribution to the development of alcoholic liver disease, steatosis and NASH. In this overview, we present the discovery of the enzyme and studies in humans, 3D liver systems and genetically modified mice to disclose its function and clinical relevance. Induction of the CYP2E1 enzyme either by alcohol or high-fat diet leads to increased severity of liver pathology and likelihood to develop ALD and NASH, with subsequent influence on the occurrence of hepatocellular cancer. Thus, fat-dependent induction of the enzyme might provide a link between steatosis and fibrosis in the liver. We conclude that CYP2E1 has many important physiological functions and is a key enzyme for hepatic carcinogenesis, drug toxicity and liver disease.

The leukotriene receptor antagonist montelukast in the treatment of non-alcoholic steatohepatitis: A proof-of-concept, randomized, double-blind, placebo-controlled trial

Non-alcoholic fatty liver disease (NAFLD) is associated with fat accumulation in the liver which can progress into non-alcoholic steatohepatitis (NASH). There is no specific treatment strategy for NASH. In this context, this study aimed at evaluating the efficacy and safety of montelukast in the treatment of patients with NASH. In this randomized double-blind placebo-controlled study, 52 overweight/obese patients with NASH were randomized into group 1 (n = 26) which received montelukast 10 mg tablets once daily and group 2 (n = 26) which received placebo tablets once daily for 12 weeks. The fibro-scan was used to assess liver stiffness as a primary outcome at baseline and 12 weeks post-treatment. Furthermore, patients were assessed for biochemical analysis of liver aminotransferases, metabolic parameters, TNF-α, 8-hydroxy-2'-deoxyguanosine (8-OHdG), liver fibrosis biomarkers including hyaluronic acid (HA) and transforming growth factor beta-1 (TGF-β1). Beck depression inventory questionnaire was used to report depressive symptoms. Data were statistically analyzed by paired and unpaired student's t-test, and Chi-square test. A total number of 44 patients completed the study. The two groups were statistically similar at baseline. After treatment and as compared to baseline data and placebo, montelukast showed a statistically significant improvement in liver stiffness, liver enzymes, metabolic parameters (except LDL-C), TNF-α, 8-OHdG, and liver fibrosis biomarkers (HA and TGF-β1). Furthermore, montelukast was well tolerated and didn't provoke depression. In this proof-of-concept study, treatment with montelukast may represent a promising therapeutic strategy for patients with non-alcoholic steatohepatitis secondary to its efficacy and safety. Clinicaltrial.gov ID: NCT04080947.

Metformin in Combination with Malvidin Prevents Progression of Non-Alcoholic Fatty Liver Disease via Improving Lipid and Glucose Metabolisms, and Inhibiting Inflammation in Type 2 Diabetes Rats

Background

Non-alcoholic fatty liver disease (NAFLD) is one of the primary causes of chronic liver disease and is closely linked to insulin resistance, type 2 diabetes mellitus (T2DM), and dyslipidemia. However, no effective drug therapies have been approved to treat this disease. The present research aimed to evaluate the therapeutic effects of the combination of oral hypoglycemic drug metformin (MET) and a natural product malvidin (MAL) on hepatic damage in HFD/STZ-induced diabetic rats.

Methods

Sprague-Dawley rats were divided into five groups: normal control group (NC), diabetic control group (DC), DC+MET group, DC+MAL group, and DC+MET+MAL group and treated for eight weeks. Blood and liver tissue samples were collected for metabolic parameters, histological, and RT-qPCR analysis.

Results

Our findings indicated that hyperglycemia, insulin resistance, hyperlipidemia, and non-alcoholic fatty liver disease (NAFLD) in diabetic rats were alleviated after oral treatment with MET and MAL, particularly their combination therapy. Besides, the expression of SREBP-1c, ACC, FAS, IL-6, IL-8, and NF-κB mRNA was down-regulated by MET+MAL, and the expression of PPARα, CPT1, and LPL was up-regulated by MET+MAL.

Conclusion

The evidence of this research indicated that the combination therapy may represent an efficient strategy against NAFLD in T2DM rats via improving lipid and glucose metabolisms, and inhibiting inflammation.

Clinical characteristics and longitudinal changes of patients with non-alcoholic fatty liver disease in 2 decades: the NAGALA study

Background

In this study, to clarify the evolving background of people with non-alcoholic fatty liver disease (NAFLD), we compared the current prevalence of NAFLD with that of 2 decades ago.

Methods

We included two cohorts. The past cohort was from 1994 to 1997 and included 4279 men and 2502 women. The current cohort was from 2014 to 2017 and included 8918 men and 7361 women. NAFLD was diagnosed by abdominal ultrasonography.

Results

The prevalence of NAFLD increased in both genders throughout these 2 decades (18.5% in the past cohort and 27.1% in the current cohort for men; and 8.0% in the past cohort and 9.4% in the current cohort for women). The prevalence of hyperglycemia increased, whereas the prevalence of low high-density lipoprotein cholesterol levels and hypertriglyceridemia significantly decreased. There was no significant difference in the mean body mass index. Multivariate analysis revealed that the prevalence of obesity and body mass index were significantly associated with the prevalence of NAFLD in both the past and current cohorts.

Conclusions

The incidence of NAFLD significantly increased throughout these 2 decades, and obesity is the most prevalent factor. Thus, body weight management is an essential treatment option for NAFLD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01809-2.

Nonalcoholic Fatty Liver Disease: Focus on New Biomarkers and Lifestyle Interventions

Nonalcoholic fatty liver disease (NAFLD) is considered a hepatic manifestation of metabolic syndrome, characterized from pathological changes in lipid and carbohydrate metabolism. Its main characteristics are excessive lipid accumulation and oxidative stress, which create a lipotoxic environment in hepatocytes leading to liver injury. Recently, many studies have focused on the identification of the genetic and epigenetic modifications that also contribute to NAFLD pathogenesis and their prognostic implications. The present review is aimed to discuss on cellular and metabolic alterations associated with NAFLD, which can be helpful to identify new noninvasive biomarkers. The identification of accumulated lipids in the cell membranes, as well as circulating cytokeratins and exosomes, provides new insights in understanding of NAFLD. This review also suggests that lifestyle modifications remain the main prevention and/or treatment for NAFLD.

'Focus on diet quality': a qualitative study of clinicians' perspectives of use of the Mediterranean dietary pattern for non-alcoholic fatty liver disease

Practice guidelines for non-alcoholic fatty liver disease (NAFLD) recommend promoting the Mediterranean dietary pattern (MDP) which is cardioprotective and may improve hepatic steatosis. This study aimed to explore multidisciplinary clinicians' perspectives on whether the MDP is recommended in routine management of NAFLD and barriers and facilitators to its implementation in a multi-ethnic setting. Semi-structured individual interviews were conducted with fourteen clinicians (seven doctors, three nurses, three dietitians and one exercise physiologist) routinely managing patients with NAFLD in metropolitan hospital outpatient clinics in Australia. Interviews were audio-recorded, transcribed and analysed using thematic content analysis. Clinicians described that lifestyle modification was their primary treatment for NAFLD and promoting diet was recognised as everyone's role, whereby doctors and nurses raise awareness and dietitians provide individualisation. The MDP was regarded as the most evidence-based diet choice currently and was frequently recommended in routine care. Facilitators to MDP implementation in practice were: improvement in diet quality as a parallel goal to weight loss; in-depth knowledge of the dietary pattern; access to patient education and monitoring resources and; service culture, including an interdisciplinary clinic goal, and knowledge sharing from expert dietitians. Barriers included perceived challenges for patients from diverse cultural and socio-economic backgrounds and limited clinician training, time and resourcing to support behaviour change. Integration of MDP in routine management of NAFLD in specialist clinics was facilitated by a focus on diet quality, knowledge sharing, belief in evidence and an interdisciplinary team. Innovations to service delivery could better support and empower patients to change dietary behaviour long-term.

HbA1c may contribute to the development of non-alcoholic fatty liver disease even at normal-range levels

Previous clinical studies highlighted nonalcoholic fatty liver disease (NAFLD) as a hepatic facet of metabolic syndrome, which progresses toward Type 2 diabetes along with an elevation of HbA1c in the blood. Longitudinal observations were performed in a cohort of 2811 participants with no liver disease at inception. The rate of the conversion into NAFLD was 15.7% (440/2811), with a steady increase in prevalence observed in sub-cohorts with increasing HbA1c levels. Moreover, regression analysis indicated that HbA1c levels serve as the risk factors for NAFLD after multiple adjustments (odds ratio: 1.58, P-value < 0.004). When HbA1c-related molecular networks were investigated using natural language programming algorithms, multiple genetic/small molecular (SM) pathways were highlighted as connectors between the HbA1c levels and the development of NAFLD, including ones for nitric oxide, hypoxia and receptor for advanced glycation end products (RAGE). Our results suggest that increased levels of HbA1c may contribute to the progression of NAFLD either directly, by stimulating RAGE or indirectly, through the promotion of hypoxia and suppression of the release of NO. Further studies are needed to test the impact of HbA1c on the development of the chronic liver disease.

Awareness of non-alcoholic steatohepatitis and treatment guidelines: What are physicians telling us?

BACKGROUND

There is an acute need to raise awareness of non-alcoholic fatty liver disease/non-alcoholic steatohepatitis (NAFLD/NASH) among primary care physicians, endocrinologists and diabetologists to improve patient identification and address the current difficulties in NASH clinical trial enrollment. We examined the extent of knowledge and practice regarding NASH diagnosis and management guidelines. A randomized online convenience survey of 12869 physicians drawn from a national physician database of primary care physicians (PCPs), and gastroenterology and endocrinology specialists were queried via online survey. Our results, based on a cohort of 185 respondents, showed gaps in knowledge and practice between these three groups of practitioners, with primary care providers having the lowest adherence to published guidelines for diagnosis of NASH. Without clear knowledge and patient identification at the point of presentation - which is often in primary care or with specialties other than hepatology–many patients with NAFLD and NASH will remain undiagnosed and untreated, and clinical studies will continue to struggle with patient recruitment, hindering clinical development and optimal patient care.

AIM

To determine knowledge base concerning NASH diagnosis amongst gastroenterologists, endocrinologists and primary care physicians to improve referrals into clinical trials.

METHODS

A randomized online convenience survey of 12869 physicians drawn from a national physician database of PCPs, and gastroenterology and endocrinology specialists was conducted yielding a sample of 185 respondents.

RESULTS

The survey revealed that many physicians are either unaware of testing options other than biopsy, or do not use them in practice. Only 46% of endocrinologists and 42% of primary care physicians indicated they would refer a patient for specialist workup if they suspected NASH. Risk (25%) and inconvenience to patients (18%) are given as reasons for not referring those with suspected NASH for biopsy. For standard diagnostic algorithms such as Fibrosis-4 score, 18% of PCPs, 30% of endocrinologists and 65% gastroenterologists reported using these tests in clinical practice.

CONCLUSION

Substantial gaps in knowledge of the differences between NAFLD and NASH exist between these physician groups, with knowledge being particularly low among primary care doctors and endocrinologists. The use of a simple non-invasive screening algorithm may help to identify the right patients for clinical trials, which in turn will be vital to the development of effective and well-tolerated treatments for this increasingly ubiquitous condition.

Dietary Polyphenols and Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD), which is emerging as a major public health issue worldwide, is characterized by a wide spectrum of liver disorders, ranging from simple fat accumulation in hepatocytes, also known as steatosis, to non-alcoholic steatohepatitis (NASH) and cirrhosis. At present, the pharmacological treatment of NAFLD is still debated and dietary strategies for the prevention and the treatment of this condition are strongly considered. Polyphenols are a group of plant-derived compounds whose anti-inflammatory and antioxidant properties are associated with a low prevalence of metabolic diseases, including obesity, hypertension, and insulin resistance. Since inflammation and oxidative stress are the main risk factors involved in the pathogenesis of NAFLD, recent studies suggest that the consumption of polyphenol-rich diets is involved in the prevention and treatment of NAFLD. However, few clinical trials are available on human subjects with NAFLD. Here, we reviewed the emerging existing evidence on the potential use of polyphenols to treat NAFLD. After introducing the physiopathology of NAFLD, we focused on the most investigated phenolic compounds in the setting of NAFLD and described their potential benefits, starting from basic science studies to animal models and human trials.

Acute Elevated Resistin Exacerbates Mitochondrial Damage and Aggravates Liver Steatosis Through AMPK/PGC-1α Signaling Pathway in Male NAFLD Mice

Resistin was identified as a link between obesity and insulin resistance and is associated with many diseases in mice. Deciphering the related development and molecular mechanism is necessary for the treatment of these diseases. Previous studies have revealed that increased resistin levels are correlated with lipid accumulation and play a role in non-alcoholic fatty liver disease (NAFLD) development. However, the exact mechanisms underlying these processes remain unclear. To further clarify whether acute elevated resistin level exacerbated liver steatosis, a high-fat diet-induced NAFLD animal model was used and treated with or without resistin for 6 days. We discovered that resistin altered mitochondrial morphology, decreased mitochondrial content, and increased lipid accumulation in HFD mice. qRT-PCR and western blot analysis showed that acute elevated resistin significantly altered the gene expression of mitochondrial biogenesis and liver lipid metabolism molecules in HFD mice. Consequently, in vitro experiments verified that resistin reduced the mitochondrial content, impaired the mitochondrial function and increased the lipid accumulation of palmitate-treated HepG2 cells. Additionally, we demonstrated that resistin upregulated proinflammatory factors, which confirmed that resistin promoted the development of inflammation in NAFLD mice and palmitate-treated HepG2 cells. Signaling-transduction analysis demonstrated that acute elevated resistin aggravated liver steatosis through AMPK/PGC-1α pathway in male mice. This reveals a novel pathway through which lipogenesis is induced by resistin and suggests that maintaining mitochondrial homeostasis may be key to treatments for preventing resistin-induced NAFLD aggravation.

The effect of the magnitude of weight loss on non-alcoholic fatty liver disease: A systematic review and meta-analysis

BACKGROUND

Trials show that weight loss interventions improve biomarkers of non-alcoholic fatty liver disease (NAFLD), but it is unclear if a dose-response relationship exists.

OBJECTIVE

We aimed to quantify the dose-response relationship between the magnitude of weight loss and improvements in NAFLD.

METHODS

Nine databases and trial registries were searched until October 2020. Single-arm, non-randomized comparative, or randomized trials of weight loss interventions (behavioral weight loss programs [BWLPs], pharmacotherapy, or bariatric surgery) in people with NAFLD were eligible for inclusion if they reported an association between changes in weight and changes in blood, radiological, or histological biomarkers of liver disease. The review followed Cochrane methods and the risk of bias was assessed using the Newcastle-Ottawa scale. Pooled unstandardized b coefficients were calculated using random-effect meta-analyses.

RESULTS

Forty-three studies (BWMPs: 26, pharmacotherapy: 9, surgery: 8) with 2809 participants were included. The median follow-up was 6 (interquartile range: 6) months. The direction of effect was generally consistent but the estimates imprecise. Every 1 kg of weight lost was associated with a 0.83-unit (95% CI: 0.53 to 1.14, p < 0.0001, I² = 92%, n = 18) reduction in alanine aminotransferase (U/L), a 0.56-unit (95% CI: 0.32 to 0.79, p < 0.0001, I² = 68%, n = 11) reduction in aspartate transaminase (U/L), and a 0.77 percentage point (95% CI: 0.51 to 1.03, p < 0.0001, I² = 72%, n = 11) reduction in steatosis assessed by radiology or histology. There was evidence of a dose-response relationship with liver inflammation, ballooning, and resolution of NAFLD or NASH, but limited evidence of a dose-response relationship with fibrosis or NAFLD activity score. On average, the risk of bias for selection and outcome was medium and low, respectively.

CONCLUSION

Clinically significant improvements in NAFLD are achieved even with modest weight loss, but greater weight loss is associated with greater improvements. Embedding support for formal weight loss programs as part of the care pathway for the treatment of NAFLD could reduce the burden of disease.

PROSPERO

CRD42018093676.

Calorie-Restricted Mediterranean and Low-Fat Diets Affect Fatty Acid Status in Individuals with Nonalcoholic Fatty Liver Disease

Lifestyle modifications are the main support of nonalcoholic fatty liver disease (NAFLD) therapy. Weight loss is one of the primary goals in NAFLD, but the effects of different calorie-restricted diets remain unclear. Thus, we evaluated the effects of two calorie-restricted diets—the Mediterranean diet (Med diet) and low-fat diet—on liver status, cardiometabolic markers, and fatty acid profiles in patients with NAFLD. Twenty-four overweight/moderately obese men were randomly assigned to consume one of these diets. Lipid levels, glucose, insulin, liver enzymes, steatosis, and fatty acid profiles of serum and erythrocytes phospholipids were assessed. After 3 months, all participants had a significant weight loss (>9%), with improvements in waist circumference, body fat %, index of visceral adiposity (VAI), lipid accumulation product, fatty liver (FLI), and hepatic steatosis (HSI) index (p < 0.001). Both diets significantly lowered triglycerides, total and LDL-cholesterol, liver enzymes, fasting glucose, insulin, and HOMA-IR index. Fatty acid profiles were enhanced after both diets, with a significantly decreased n-6/n-3 ratio. Participants on the Med diet had higher levels of HDL-cholesterol and monounsaturated and n-3 docosahexaenoic acids in serum phospholipids and lower levels of saturated fatty acids, triglycerides, TG/HDL ratio, and FLI when compared to participants on the low-fat diet. Our results indicate that dietary patterns and calorie restriction represent central therapeutic issues in the improvement of obesity-related cardiometabolic alterations that are involved in the mechanism of hepatic steatosis. The Med diet may contribute to disease treatment even more than the low-fat diet since it leads to decreased saturated and increased monounsaturated and n-3 polyunsaturated fatty acid status and improved FLI in NAFLD patients.

Prospective association between adherence to the Mediterranean diet and hepatic steatosis: the Swiss CoLaus cohort study

OBJECTIVE

The Mediterranean diet has been promoted as a healthy dietary pattern, but whether the Mediterranean diet may help to prevent hepatic steatosis is not clear. This study aimed to evaluate the prospective association between adherence to the Mediterranean diet and risk of hepatic steatosis.

DESIGN

Population-based prospective cohort study.

SETTING

The Swiss CoLaus Study.

PARTICIPANTS

We evaluated 2288 adults (65.4% women, aged 55.8±10.0 years) without hepatic steatosis at first follow-up in 2009-2012. Adherence to the Mediterranean diet was scaled as the Mediterranean diet score (MDS) based on the Mediterranean diet pyramid ascertained with responses to Food Frequency Questionnaires.

OUTCOME MEASURES

New onset of hepatic steatosis was ascertained by two indices separately: the Fatty Liver Index (FLI, ≥60 points) and the non-alcoholic fatty liver disease (NAFLD) score (≥-0.640 points). Prospective associations between adherence to the Mediterranean diet and risk of hepatic steatosis were quantified using Poisson regression.

RESULTS

During a mean 5.3 years of follow-up, hepatic steatosis was ascertained in 153 (6.7%) participants by FLI criteria and in 208 (9.1%) by NAFLD score. After multivariable adjustment, higher adherence to MDS was associated with lower risk of hepatic steatosis based on FLI: risk ratio 0.84 (95% CI 0.73 to 0.96) per 1 SD of MDS; 0.85 (0.73 to 0.99) adjusted for BMI; and 0.85 (0.71 to 1.02) adjusted for both BMI and waist circumference. When using NAFLD score, no significant association was found between MDS and risk of hepatic steatosis (0.95 (0.83 to 1.09)).

CONCLUSION

A potential role of the Mediterranean diet in the prevention of hepatic steatosis is suggested by the inverse association observed between adherence to the Mediterranean diet and incidence of hepatic steatosis based on the FLI. The inconsistency of this association when hepatic steatosis was assessed by NAFLD score points to the need for accurate population-level assessment of fatty liver and its physiological markers.

Transplantation of brown adipose tissue up-regulates miR-99a to ameliorate liver metabolic disorders in diabetic mice by targeting NOX4

Nonalcoholic fatty liver disease (NAFLD), main cause of liver damage, is inextricably linked to diabetes. However, there is no specific means to improve the pathology of fatty liver in diabetic patients. Brown adipose tissue (BAT) is an important endocrine organ that secretes adipokines and microRNAs (miRNAs) involved in systemic metabolic regulation. To investigate the effects of BAT transplantation on liver lipid metabolism in diabetic mice, we transplanted BAT from male donor mice into diabetic mice induced by streptozotocin (STZ) combined with high-fat diet (HFD). At 10 weeks after transplantation, BAT transplantation significantly decreased the blood glucose and lipid, downregulated FAS, CD36, Scd1, ACCα, NOX2, NOX4, TGF-β1, FN and COL-1, up-regulated Nrf2, reversed the pathological changes of liver and increased the circulating miR-99a in diabetic mice. To verify whether circulating miR-99a improves oxidative stress by targeting inhibition of NOX4, we used 0.4mM palmitic acid (PA) to treat the LO2 cells. The expression of NOX4 protein was significantly decreased after transfection with miR-99a mimic, and increased after transfection with miR-99a inhibitor. Luciferase reporter assay confirmed that miR-99a could target NOX4 mRNA. These findings clarify the role of miR-99a and NOX4 in liver beneficial effect of BAT transplantation in diabetic mice.

Estimation of visceral fat is useful for the diagnosis of significant fibrosis in patients with non-alcoholic fatty liver disease

BACKGROUND

Obesity is a risk factor for non-alcoholic fatty liver disease (NAFLD), although obese patients with NAFLD do not always develop significant fibrosis. The distribution of body fat could predict the risk of NAFLD progression. 

AIM

To investigate the role of bioelectrical impedance-estimated visceral fat (VF) in assessing NAFLD severity.

METHODS

In this cross-sectional study, patients with biopsy-proven NAFLD were prospectively included. All patients underwent anthropometric evaluation, blood tests and bioelectrical impedance analysis.

RESULTS

Between 2017 and 2020, 119 patients were included [66.4% male, 56 years (SD 10.7), 62.2% obese, 61.3% with metabolic syndrome]. Sixty of them (50.4%) showed significant fibrosis (≥ F2) in liver biopsy. Age, VF and metabolic syndrome were associated with significant fibrosis (61 years vs 52 years, 16.4 vs 13.1, 73.3% vs 49.2%, respectively; P < 0.001 for all). In the multivariate analysis, VF and age were independently associated with significant fibrosis (VF, OR: 1.11, 95%CI: 1.02-1.22, P = 0.02; age, OR: 1.08, 95%CI: 1.03-1.12, P < 0.01). A model including these variables showed and area under the receiver operating characteristic curve (AUROC) of 0.75, which was not inferior to transient elastography or NAFLD fibrosis score AUROCs. We developed a nomogram including age and VF for assessing significant fibrosis in routine practice.

CONCLUSION

VF is a surrogate marker of liver fibrosis in patients with NAFLD. Bioelectrical impedance analysis is an inexpensive and simple method that can be combined with age to guide patient referral when other resources may be unavailable.

The effect of adiponectin in the pathogenesis of non-alcoholic fatty liver disease (NAFLD) and the potential role of polyphenols in the modulation of adiponectin signaling

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide, as it affects up to 30 % of adults in Western countries. Moreover, NAFLD is also considered an independent risk factor for cardiovascular diseases. Insulin resistance and inflammation have been identified as key factors in the pathophysiology of NAFLD. Although the mechanisms associated with the development of NAFLD remain to be fully elucidated, a complex interaction between adipokines and cytokines appear to play a crucial role in the development of this condition. Adiponectin is the most common adipokine known to be inversely linked with insulin resistance, lipid accumulation, inflammation and NAFLD. Consequently, the focus has been on the use of new therapies that may enhance hepatic expression of adiponectin downstream targets or increase the serum levels of adiponectin in the treatment NAFLD. While currently used therapies show limited efficacy in this aspect, accumulating evidence suggest that various dietary polyphenols may stimulate adiponectin levels, offering potential protection against the development of insulin resistance, inflammation and NAFLD as well as associated conditions of metabolic syndrome. As such, this review provides a better understanding of the role polyphenols play in modulating adiponectin signaling to protect against NAFLD. A brief discussion on the regulation of adiponectin during disease pathophysiology is also covered to underscore the potential protective effects of polyphenols against NAFLD. Some of the prominent polyphenols described in the manuscript include aspalathin, berberine, catechins, chlorogenic acid, curcumin, genistein, piperine, quercetin, and resveratrol.

Gut Microbiota and Liver Interaction through Immune System Cross-Talk: A Comprehensive Review at the Time of the SARS-CoV-2 Pandemic

Background and aims: The gut microbiota is a complex ecosystem containing bacteria, viruses, fungi, yeasts and other single-celled organisms. It is involved in the development and maintenance of both innate and systemic immunity of the body. Emerging evidence has shown its role in liver diseases through the immune system cross-talk. We review herein literature data regarding the triangular interaction between gut microbiota, immune system and liver in health and disease. Methods: We conducted a search on the main medical databases for original articles, reviews, meta-analyses, randomized clinical trials and case series using the following keywords and acronyms and their associations: gut microbiota, microbiome, gut virome, immunity, gastrointestinal-associated lymphoid tissue (GALT), non-alcoholic fatty liver disease (NAFLD), non-alcoholic steato-hepatitis (NASH), alcoholic liver disease, liver cirrhosis, hepatocellular carcinoma. Results: The gut microbiota consists of microorganisms that educate our systemic immunity through GALT and non-GALT interactions. The latter maintain health but are also involved in the pathophysiology and in the outcome of several liver diseases, particularly those with metabolic, toxic or immune-mediated etiology. In this context, gut virome has an emerging role in liver diseases and needs to be further investigated, especially due to the link reported between severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection and hepatic dysfunctions. Conclusions: Changes in gut microbiota composition and alterations in the immune system response are involved in the pathogenesis of metabolic and immune-mediated liver diseases.

Adherence to a plant-based diet in relation to adipose tissue volumes and liver fat content

BACKGROUND

Better adherence to plant-based diets has been linked to lower risk of metabolic diseases but the effect on abdominal fat distribution and liver fat content is unclear.

OBJECTIVES

We aimed to examine the association between different plant-based diet indices and measures of abdominal fat distribution and liver fat content.

METHODS

In a population-based sample of 578 individuals from Northern Germany (57% male, median age 62 y), diet was assessed with a validated FFQ and an overall, a healthy, and an unhealthy plant-based diet index were derived. Participants underwent MRI to assess volumes of visceral and subcutaneous abdominal adipose tissue and liver signal intensity (LSI), a measure of liver fat content. Fatty liver disease (FLD) was defined as log LSI ≥3.0. Cross-sectional associations of the plant-based diet indices with visceral and subcutaneous abdominal fat volumes, LSI, and FLD were assessed in linear and logistic regression analyses. The most comprehensive model adjusted for age, sex, education, smoking, alcohol, physical activity, energy intake, diabetes, hyperlipidemia, and BMI.

RESULTS

Higher overall and healthy plant-based diet indices both revealed statistically significant associations with lower visceral and subcutaneous abdominal adipose tissue volumes and with lower odds of FLD in multivariable-adjusted models without BMI. Upon additional adjustment for BMI, only the association of the healthy plant-based diet with visceral adipose tissue remained statistically significant (per 10-point higher healthy plant-based diet index, percentage change in visceral adipose tissue: -4.9%, 95% CI: -8.6%, -2.0%). None of the plant-based diet indices was associated with LSI. The unhealthy plant-based diet index was unrelated to any of the abdominal or liver fat parameters.

CONCLUSIONS

Adherence to healthy plant-based diets was associated with lower visceral adipose tissue. None of the other examined associations remained statistically significant after adjustment for BMI.

Association between eating speed and newly diagnosed nonalcoholic fatty liver disease among the general population

Fast eating speed is a risk factor for obesity, which is also closely related to nonalcoholic fatty liver disease (NAFLD), suggesting that fast eating speed may contribute to the development of NAFLD. But the extent to which obesity may mediate the association between eating speed and NAFLD is uncertain. We hypothesized that obesity plays a mediating role in the association between eating speed and prevalence of NAFLD in the general population. A cross-sectional study (n = 23,611) was conducted in a general population sample from Tianjin, China. We measured anthropometrics and biochemical variables. The self-reported eating speed per meal was recorded and classified into 4 categories: slow, medium, relatively fast, and very fast. NAFLD was diagnosed by liver ultrasonography. Multiple logistic regression analysis was used to assess the associations between the eating speed and the prevalence of NAFLD, as well as the mediation effects of obesity on the association between eating speed and NAFLD. The prevalence of newly diagnosed NAFLD was 19.0%. After adjusting for potentially confounding factors, the odds ratios (95% confidence interval) of NAFLD across categories of eating speed were 1.00 (reference), 1.39 (1.18-1.64), 1.71 (1.45-2.01), and 2.04 (1.70-2.46). All these significant odds ratios were attenuated to be nonsignificant by adjustment for body mass index and/or waist circumference. This is the first study to demonstrate that eating speed is not independently associated with increased risk of NAFLD.

Correlation between serum proinsulin levels and fatty liver: The Dynamics of Lifestyle and Neighborhood Community on Health Study

AIMS/INTRODUCTION

We explored the association between fatty liver and pancreatic β-cell dysfunction in a general population.

MATERIALS AND METHODS

This cross-sectional study included 489 (53.8% women) community-dwelling Japanese adults. The extent of fatty liver was estimated using the fatty liver index (FLI). After all participants were divided into three groups - low (FLI <30), moderate (30 ≤FLI <60) or high (FLI ≥ 60) degree of fatty liver - serum proinsulin levels transformed into natural logarithms were compared among the three groups. To determine whether obesity modified the association of interest, the participants were stratified into two groups according to the median body mass index. Next, to determine whether hyperinsulinemia modified the association of interest, a similar stratified analysis was carried out using the median serum insulin level.

RESULTS

Logarithm (proinsulin) was significantly higher in the high FLI group than in the moderate and low groups, and it was significantly higher in the moderate group than in the low group after adjustment for age and sex (P < 0.05). Logarithm (proinsulin) was significantly higher in the high FLI group than in the low FLI group, regardless of body mass index, after adjustment for age and sex. A similar pattern was observed regardless of serum insulin levels.

CONCLUSIONS

The degree of fatty liver was positively associated with proinsulin level, regardless of the presence of obesity or hyperinsulinemia, suggesting that fatty liver reflects pancreatic β-cell dysfunction.

Association between NAFLD and risk of prevalent chronic kidney disease: why there is a difference between east and west?

Backgrounds

There is a discrepancy between west and east on the relationship between non-alcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD). This study aimed to find out the possible reason for this and to clarify the association between NAFLD and CKD by analyzing two population-based datasets from the US and China.

Methods

Two health examination datasets from China and the US were used. CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73m² or and/or abnormal albuminuria and/or overt proteinuria. Binary logistic regression was used to examine the association between NAFLD and CKD.

Results

A total of 60,965 participants were analyzed, including 11,844 from the US and 51,229 from China. The prevalence of NAFLD was 27.12% in the Chinese population and 36.08% in the US population (p < 0.001). The proportions of CKD and late stage CKD (stages 3–5) were higher in the US population than the Chinese one. NAFLD was independently associated with an increased risk of CKD in Chinese population, whereas in the US population, the NAFLD was not an independent risk factor of CKD. In subgroup analyses which excluded late stages CKD (stages 3–5), the risks of mild renal function decline became consistent: NAFLD was associated with early stages of CKD but not the late stages of CKD in both populations.

Conclusion

NAFLD increased the risk of early stages of CKD in both Chinese and the US population. The conflicting results reported by previous studies might result from the different proportion of late stages of CKD.