Non-alcoholic fatty liver disease and obesity: Biochemical, metabolic and clinical presentations

Beneficial Effects of the Ketogenic Diet in Metabolic Syndrome: A Systematic Review

Metabolic syndrome (MetS) is a major societal concern due to its increasing prevalence and its high risk of cardiovascular complications. The ketogenic diet (KD), a high fat, low carbohydrate, and non-caloric restrictive diet, is a new popular weight loss intervention but its beneficial effects are controversial. This study aims to gather all of the relevant studies using KD for metabolic disease treatment to determine its beneficial effects and evaluate its safety and efficacy for patients. Following the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, we included 20 articles in the final review. Overall, most of the studies showed a significant effect of KD on weight loss (17/19 articles), BMI (7/7), glucose levels (9/13), insulin levels (7/9), HOMA-IR (4/5), HbA1c (7/7), total cholesterol (6/9), TG (13/15), AST (3/4), and ALT (3/5), and no major side effects. The results heterogeneity seems to be explained by a difference of diet composition and duration. In conclusion, KD is a safety diet which seems to be a promising approach for obesity and MetS treatment, even if the optimal carbohydrate proportion and diet duration must be explored to enhance the beneficial effects of KD.

Non-alcoholic Fatty Liver Disease and Steatohepatitis: Risk Factors and Pathophysiology

Non-alcoholic fatty liver disease (NAFLD) and its progressive subtype non-alcoholic steatohepatitis (NASH) are the most prevalent liver diseases, often leading to hepatocellular carcinoma (HCC). This review aims to describe the present knowledge of the risk factors responsible for the development of NAFLD and NASH. I performed a literature review identifying studies focusing on the complex pathogenic pathway and risk factors of NAFLD and steatohepatitis. The relationship between NAFLD and metabolic syndrome is well established and widely recognized. Obesity, dyslipidemia, type 2 diabetes, hypertension, and insulin resistance are the most common risk factors associated with NAFLD. Among the components of metabolic syndrome, current evidence strongly suggests obesity and type 2 diabetes as risk factors of NASH and HCC. However, other elements, namely gender divergences, ethnicity, genetic factors, participation of innate immune system, oxidative stress, apoptotic pathways, and adipocytokines, take a leading role in the onset and promotion of NAFLD. Pathophysiological mechanisms that are responsible for NAFLD development and subsequent progression to NASH are insulin resistance and hyperinsulinemia, oxidative stress, hepatic stellate cell (HSC) activation, cytokine/adipokine signaling pathways, and genetic and environmental factors. Major pathophysiological findings of NAFLD are dysfunction of adipose tissue through the enhanced flow of free fatty acids (FFAs) and release of adipokines, and altered gut microbiome that generate proinflammatory signals and cause NASH progression. Understanding the pathophysiology and risk factors of NAFLD and NASH; this review could provide insight into the development of therapeutic strategies and useful diagnostic tools.

Tilapia-Head Chondroitin Sulfate Protects against Nonalcoholic Fatty Liver Disease via Modulating the Gut-Liver Axis in High-Fat-Diet-Fed C57BL/6 Mice

We isolated and characterized tilapia-head chondroitin sulfate (TH-CS) and explored its biological activity and mechanisms of action as an oral supplement for nonalcoholic fatty liver disease (NAFLD) induced by a high-fat diet (HFD) in mice. The results showed that treatment with TH-CS for 8 weeks alleviated the development of NAFLD, as evidenced by the notable improvement in liver damage, blood lipid accumulation and insulin resistance (IR). Meanwhile, TH-CS treatment reduced the expression of proinflammatory cytokines and normalized oxidative stress. Additionally, the analysis of 16S rDNA sequencing revealed that TH-CS could restore gut microbiota balance and increase the relative abundance of short-chain fatty acid (SCFA)-producing bacteria. Furthermore, SCFAs produced by related bacteria can further improve lipid metabolism and IR by regulating lipid synthesis signals. In conclusion, TH-CS is an effective dietary supplement for the prevention of NAFLD, and may serve as a potential supplementary treatment for lipid-related metabolic syndrome.

Cardiovascular Risk Is Elevated in Lean Subjects with Nonalcoholic Fatty Liver Disease

BACKGROUND/AIMS

: Nonalcoholic fatty liver disease (NAFLD) and obesity are independently associated with an increased risk for atherosclerotic cardiovascular disease (ASCVD), the leading cause of mortality in patients with NAFLD. Many NAFLD patients are lean, but their ASCVD risk compared to obese subjects with NAFLD is unclear.

METHODS

Data from the 2008 to 2011 Korea National Health and Nutrition Examination Surveys database were analyzed (n=4,786). NAFLD was defined as a comprehensive NAFLD score ≥40 or a liver fat score ≥-0.640. ASCVD risk was evaluated using the American College of Cardiology/ American Heart Association guidelines.

RESULTS

The frequency of subjects without NAFLD, with obese NAFLD, and with lean NAFLD was 62.4% (n=2,987), 26.6% (n=1,274), and 11.0% (n=525), respectively. Subjects with lean NAFLD had a significantly higher ASCVD score and prevalence of a high ASCVD risk (mean 15.6±14.0, 51.6%) than those with obese NAFLD and without NAFLD (mean 11.2±11.4, 39.8%; mean 7.9±10.9, 25.5%; all p<0.001). Subjects with lean NAFLD and significant liver fibrosis showed a significantly higher odds ratio for a high risk for ASCVD than those with obese NAFLD with or without significant liver fibrosis (odds ratio, 2.60 vs 1.93; p=0.023).

CONCLUSIONS

Subjects with lean NAFLD had a significantly higher ASCVD score and prevalence of high risk for ASCVD than those with obese NAFLD. Similarly, lean subjects with significant liver fibrosis had a higher probability of ASCVD than obese subjects in the subpopulation with NAFLD.

A combined association of serum uric acid, alanine aminotransferase and waist circumference with non-alcoholic fatty liver disease: a community-based study

Background

Increasing evidence has supported that serum uric acid (SUA), alanine aminotransferase (ALT) and waist circumference (WC) are associated with the occurrence of non-alcoholic fatty liver disease (NAFLD). However, the combined role of these factors in early screening of NAFLD has not been investigated. We aimed to de lineate this role in a community-based population.

Methods

Binary logistic regression was used to explore the correlations of SUA, ALT and WC with NAFLD risk. The goodness of fit and discriminative ability of the model were evaluated by the Hosmer-Lemeshow test and area under the receiver operating characteristic curve (AUROC), respectively.

Results

Logistic regression analysis indicated that elevated SUA (adjusted odds ratio (OR) = 2.44, 95% confidence interval (CI) [1.76-3.38]), ALT (adjusted OR = 4.98, 95% CI [3.41-7.27]) and WC (adjusted OR = 3.22, 95% CI [2.01-5.16]) were facilitating factors for incident NAFLD after fully adjusted for related confounders. In addition, the risk of NAFLD followed linear trend s with increasing levels of these three indicators (all P _trend < 0.001). The risk assessment model consisting of SUA, ALT, WC and demographics showed useful discrimination by AUROC being 0.825 (95% CI [0.811-0.838]) and good performance of calibration (P = 0.561).

Conclusions

SUA, ALT and WC were all associated with NAFLD, independent of known risk factors. The simple model composed of these indicators showed good performance in the Chinese population, which may be applicable for appraisal of NAFLD risk in primary healthcare.

Adiposity, metabolomic biomarkers, and risk of nonalcoholic fatty liver disease: a case-cohort study

BACKGROUND

Globally, the burden of obesity and associated nonalcoholic fatty liver disease (NAFLD) are rising, but little is known about the role that circulating metabolomic biomarkers play in mediating their association.

OBJECTIVES

We aimed to examine the observational and genetic associations of adiposity with metabolomic biomarkers and the observational associations of metabolomic biomarkers with incident NAFLD.

METHODS

A case-subcohort study within the prospective China Kadoorie Biobank included 176 NAFLD cases and 180 subcohort individuals and measured 1208 metabolites in stored baseline plasma using a Metabolon assay. In the subcohort the observational and genetic associations of BMI with biomarkers were assessed using linear regression, with adjustment for multiple testing. Cox regression was used to estimate adjusted HRs for NAFLD associated with biomarkers.

RESULTS

In observational analyses, BMI (kg/m2; mean: 23.9 in the subcohort) was associated with 199 metabolites at a 5% false discovery rate. The effects of genetically elevated BMI with specific metabolites were directionally consistent with the observational associations. Overall, 35 metabolites were associated with NAFLD risk, of which 15 were also associated with BMI, including glutamate (HR per 1-SD higher metabolite: 1.95; 95% CI: 1.48, 2.56), cysteine-glutathione disulfide (0.44; 0.31, 0.62), diaclyglycerol (C32:1) (1.71; 1.24, 2.35), behenoyl dihydrosphingomyelin (C40:0) (1.92; 1.42, 2.59), butyrylcarnitine (C4) (1.91; 1.38, 2.35), 2-hydroxybehenate (1.81; 1.34, 2.45), and 4-cholesten-3-one (1.79; 1.27, 2.54). The discriminatory performance of known risk factors was increased when 28 metabolites were also considered simultaneously in the model (weighted C-statistic: 0.84 to 0.90; P  < 0.001).

CONCLUSIONS

Among relatively lean Chinese adults, a range of metabolomic biomarkers are associated with NAFLD risk and these biomarkers may lie on the pathway between adiposity and NAFLD.

Gender-Based Association of Coronary Artery Calcification and Framingham Risk Score With Non-alcoholic Fatty Liver Disease and Abdominal Obesity in Taiwanese Adults, a Cross-Sectional Study

Background

It is not certain whether non-alcoholic fatty liver disease (NAFLD) or abdominal obesity (AO) has stronger associations with atherosclerosis and coronary artery disease (CAD) risk across different genders. The purpose of this study was to determine the gender-based association of NAFLD and AO with subclinical atherosclerosis represented by coronary artery calcification (CAC) and CAD risk by Framingham risk score (FRS).

Methods

A total of 1,655 participants in a health-screening program (mean age: 49.44 years; males: 70.33%) were enrolled for analysis. Fatty liver and coronary artery calcium score (CACS) were measured via ultrasonography (US) and multi-detector computed tomography (MDCT). The presence of CAC was defined as having a CACS > 0, intermediate to high CAD risk was defined as FRS ≥ 10%, while the presence of AO was defined as having a waist circumference (WC) of ≥90 cm for men and ≥80 cm for women. Participants were categorized into four groups depending on the presence or absence of NAFLD and/or AO.

Results

The percentage of subjects with CACS > 0 was highest in the AO-only group (overall: 42.6%; men: 48.4%; women: 35.8%); and FRS ≥ 10% was highest in the group with both abnormalities (overall: 50.3%%; men: 57.3%; women: 32.4%). After adjustment factors, the odds ratio (OR) for CAC and FRS was the highest in the group with both abnormalities [men: 1.61 (1.13–2.30) for CACS > 0 and 5.86 (3.37–10.20) for FRS ≥ 10%; women: 2.17 (1.13–4.16) for CACS > 0 and 6.31 (2.08–19.10) for FRS ≥ 10%]. In men, the OR of NAFLD was higher than that of AO [1.37 (1.03–1.83) vs. 1.35 (1.02–1.79) for CACS > 0, 3.26 (2.13–4.98) vs. 2.97 (1.91–4.62) for FRS ≥ 10%]. However, women with AO consistently showed increased OR for CACS > 0 [1.87 (1.11–3.16)] and FRS ≥ 10% [4.77 (2.01–11.34)].

Conclusion

The degree of association of NAFLD and AO with CAC and FRS depends on the gender. NAFLD is more closely associated with CACS > 0 and FRS ≥ 10% in men and AO in women, respectively. NAFLD and AO could be considered independent determinants of CAC and FRS by gender.

Ganoderic acid A ameliorates non‑alcoholic streatohepatitis (NASH) induced by high‑fat high‑cholesterol diet in mice

Non-alcoholic steatohepatitis (NASH) is becoming a huge global health problem. Previous studies have revealed that ganoderic acids have hepatoprotective and hypocholesterolemic effects. In the present study, to evaluate the anti-NASH activity of ganoderic acid A (GAA), male 6-week-old C57BL/6J mice were divided into the following four groups, which were administered different diets: Normal diet (ND group), high-fat high-cholesterol diet (HFHC group), HFHC diet supplemented with 25 mg/kg/day (GAAL group) or 50 mg/kg/day of GAA (GAAH group). After 12 weeks of GAA treatment, histopathological results revealed that compared with that of the HFHC group, GAA significantly inhibited fat accumulation, steatosis, inflammation and fibrosis in the liver. GAA effectively reduced serum aspartate transaminase and alanine transaminase levels compared with the HFHC model. Furthermore, the endoplasmic reticulum (ER) stress-responsive proteins, including glucose-regulated protein 78, phosphorylated (p)-eukaryotic initiation factor-2α and p-JNK, were significantly suppressed by GAA, while ERp57, p-MAPK and p-AKT were significantly increased after GAA treatment. Taken together, it was concluded that GAA could resist HFHC diet-induced NASH. In terms of its underlying mechanism, GAA could improve liver inflammation and fibrosis by inhibiting hepatic oxidative stress and the ER stress response induced by HFHC.

The Risk Factors of Nonalcoholic Fatty Liver Disease in Morbidly Obese Patients Undergoing Bariatric Surgery in Iran

Background and Aims. Nonalcoholic fatty liver disease (NAFLD) is common in severely obese individuals undergoing bariatric surgery. Assessing the prevalence and severity of NAFLD seems crucial since it may affect the prevention or development of more severe forms of fatty liver. Methods. This cross-sectional study was conducted on 228 severely obese individuals undergoing bariatric surgery. Abdominal ultrasonography was done, and clinical and biochemical factors (liver enzymes, lipid profile, and fasting blood sugar (FBS)) were assessed. Results. The mean body mass index (BMI) was $43.45\pm 5.92$  kg/m2. The prevalence of NAFLD was 49.12% (mild steatosis: 37.5%, moderate steatosis: 36.6%, and severe steatosis: 25.8%). The main risk factors of NAFLD were weight ( $p=0.002$ ), BMI ( $p=0.003$ ), alanine aminotransferase (ALT) ( $p<0.001$ ), aspartate aminotransferase (AST) ( $p<0.001$ ), serum triglycerides (TGs) ( $p=0.004$ ), and FBS ( $p=0.039$ ). The results revealed a statistically significant decrease in the mean level of high-density lipoprotein cholesterol (HDL-C) ( $p=0.044$ ). However, no significant association was found between the severity of liver steatosis and the presence of comorbidities such as hypertension, diabetes, hypothyroidism, and dyslipidemia. Conclusions. More severe NAFLD was associated with increased weight and BMI. Elevated ALT, AST, TG, and FBS levels and decreased HDL-C levels were also the risk factors of NAFLD and its progress to more severe conditions.

Pericardial fat, thoracic peri-aortic adipose tissue, and systemic inflammatory marker in nonalcoholic fatty liver and abdominal obesity phenotype

Researchers have conducted many studies about the relationships between peri-cardiovascular fat, nonalcoholic fatty liver disease (NAFLD), waist circumference, and cardiovascular disease (CVD). Nevertheless, the relationship between NAFLD and pericardial fat (PCF)/thoracic peri-aortic adipose tissue (TAT) phenotypes was still unknown. This study aimed to explore whether PCF/TAT was associated with NAFLD/abdominal obesity (AO) phenotypes in different high-sensitivity C-reactive protein (hs-CRP) levels. We consecutively studied 1655 individuals (mean age, 49.44 ± 9.76 years) who underwent a health-screening program. We showed a significant association between PCF/TAT and NAFLD/AO phenotypes in the cross-sectional study. We observed that the highest risk occurred in both abnormalities' groups, and the second highest risk occurred in the AO-only group. Subjects with AO had a significantly increased risk of PCF or TAT compared to those with NAFLD. Notably, the magnitude of the associations between PCF/TAT and NAFLD/AO varied by the level of systemic inflammatory marker (hs-CRP level). We suggested that people with AO and NAFLD must be more careful about changes in PCF and TAT. Regular measurement of waist circumference (or AO) can be a more accessible way to monitor peri-cardiovascular fat (PCF and TAT), which may serve as a novel and rapid way to screen CVD in the future.

Sitagliptin Is More Effective Than Gliclazide in Preventing &nbsp;Pro-Fibrotic and Pro-Inflammatory Changes in a Rodent Model of Diet-Induced Non-Alcoholic Fatty Liver Disease

A diet-induced non-alcoholic fatty liver disease (NAFLD) model causing obesity in rodents was used to examine whether sitagliptin and gliclazide therapies have similar protective effects on pathological liver change.

METHODS

Male mice were fed a high-fat diet (HFD) or standard chow (Chow) ad libitum for 25 weeks and randomly allocated to oral sitagliptin or gliclazide treatment for the final 10 weeks. Fasting blood glucose and circulating insulin were measured. Inflammatory and fibrotic liver markers were assessed by qPCR. The second messenger ERK and autophagy markers were examined by Western immunoblot. F4/80, collagens and CCN2 were assessed by immunohistochemistry (IHC).

RESULTS

At termination, HFD mice were obese, hyperinsulinemic and insulin-resistant but non-diabetic. The DPP4 inhibitor sitagliptin prevented intrahepatic induction of pro-fibrotic markers collagen-IV, collagen-VI, CCN2 and TGF-β1 and pro-inflammatory markers TNF-α and IL-1β more effectively than sulfonylurea gliclazide. By IHC, liver collagen-VI and CCN2 induction by HFD were inhibited only by sitagliptin. Sitagliptin had a greater ability than gliclazide to normalise ERK-protein liver dysregulation.

CONCLUSION

These data indicate that sitagliptin, compared with gliclazide, exhibits greater inhibition of pro-fibrotic and pro-inflammatory changes in an HFD-induced NAFLD model. Sitagliptin therapy, even in the absence of diabetes, may have specific benefits in diet-induced NAFLD.

Mediterranean Diet and Fatty Liver Risk in a Population of Overweight Older Italians: A Propensity Score-Matched Case-Cohort Study

Hepatic steatosis, often known as fatty liver, is the most common hepatic disease in Western countries. The latest guidelines for the treatment of nonalcoholic fatty liver disease emphasize lifestyle measures, such as changing unhealthy eating patterns. Using a propensity score-matching approach, this study investigated the effect of adhering to a Mediterranean diet (MedDiet) on fatty liver risk in an older population (≥65 years) from Southern Italy. We recruited 1.403 subjects (53.6% men, ≥65 years) who completed a food frequency questionnaire (FFQ) and underwent clinical assessment between 2015 and 2018. For the assessment of the liver fat content, we applied the Fatty Liver Index (FLI). To evaluate the treatment effect of the MedDiet, propensity score matching was performed on patients with and without FLI > 60. After propensity score-matching with the MedDiet pattern as treatment, we found a higher consumption of red meat (p = 0.04) and wine (p = 0.04) in subjects with FLI > 60. Based on the FLI, the inverse association shown between adherence to the MedDiet and the risk of hepatic steatosis shows that the MedDiet can help to prevent hepatic steatosis. Consuming less red and processed meat, as well as alcoholic beverages, may be part of these healthy lifestyle recommendations.

Diagnostic Value of Neutrophil to Lymphocyte Ratio in Non-Alcoholic Fatty Liver Disease Evaluated Using Transient Elastography (TE) with Controlled Attenuated Parameter (CAP)

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a chronic inflammatory disease with excessive fat accumulation in the liver. Transient elastography (TE) with controlled attenuation parameter (CAP) is a device and method to examine the degree of fibrosis and steatosis. However, this device is not widely available across Indonesia. Neutrophil and lymphocyte ratio (NLR) is a simple marker for inflammation, which has a potency to predict disease outcome. This study aims to know the diagnostic value of NLR as the indicator of steatosis and fibrosis severity.

METHODS

This was a cross-sectional study with consecutive sample collection. We used secondary data from medical records, starting from 2016 to 2018. A descriptive and data analysis, including correlation test, multivariate linear regression, t-test, receiver operating curve (ROC) and area under the curve (AUC) were done to find out the outcome of the study. Statistical analyses were performed using Statistical Package for Social Sciences (SPSS) Version 20.0 (SPSS Inc, Chicago, Illinois). A P value <0.05 was considered as statistically significant.

RESULTS

Out of 106 subjects, 62.3% patients were women with the mean of age 57.29 years old and 77.4% had metabolic syndrome. Most patients had moderate to severe steatosis degree (66%) with the mean of TE mean 6.14 (2.8-18.2) kPa. There was a positive correlation between CAP and TE compared with NLR with r = 0.648 (p < 0.001) and r = 0.621 (p < 0.001), respectively. The use of RNL to assess moderate-severe steatosis has a cutoff point of 1.775 with sensitivity, specificity, PPV and NPV, respectively, at 81.5%, 80.6%, 89.1%, and 69.1%; cutoff point 2.150 to assess significant fibrosis with sensitivity, specificity, PPV and NPV of 92.3%, 87.5%, 70.6%, and 97.2%, respectively.

CONCLUSION

NLR has a positive and significant correlation with the degree of steatosis and fibrosis with high sensitivity and specificity as evaluated by TE/CAP.

High-Sensitive CRP Correlates With the Severity of Liver Steatosis and Fibrosis in Obese Patients With Metabolic Dysfunction Associated Fatty Liver Disease

BACKGROUND

Metabolic dysfunction associated fatty liver disease (MAFLD) is the most common hepatopathy worldwide due to the obesity epidemic and is associated with chronic low-grade inflammation. High-sensitive C-reactive protein (hsCRP) as an inflammatory marker has been used in diagnosing MAFLD. However, the association between hsCRP and the severity of liver steatosis and fibrosis among obese patients with MAFLD remains to be elucidated.

OBJECTIVE

To explore the correlation of hsCRP with the severity of liver steatosis and fibrosis among Chinese obese patients with MAFLD.

METHODS

A total of 393 obese patients with mean BMI 34.8 ± 6.6 kg/m² were selected and categorized as MAFLD and non-MAFLD groups. Anthropometric data, biochemical indices, and hsCRP were measured. The severity of hepatic steatosis and fibrosis was assessed using FibroScan. Multivariate logistic regression analysis was performed to determine the relationship between hsCRP and the risk of MAFLD and its disease severity.

RESULTS

Patients with MAFLD showed significantly elevated hsCRP levels and were more likely to have severe steatosis and fibrosis compared to those without MAFLD. The proportions of MAFLD, severe steatosis, and severe fibrosis were significantly increased across the hsCRP quartiles (P-trend = 0.004, 0.021, and 0.006, respectively). After multivariable adjustments, the adjusted ORs (AORs) and 95%CI for MAFLD were 1.00 (reference), 1.298 (0.587-2.872), 2.407 (1.002-5.781), and 2.637(1.073-6.482) (Q1-Q4, P-trend = 0.014). Likewise, the AORs (95%CI) for severe steatosis and severe fibrosis were remarkably increased with the increment of serum hsCRP quartiles (P-trend < 0.001, P-trend = 0.021, respectively).

CONCLUSIONS

Elevated serum hsCRP levels were associated with increased risk of MAFLD among Chinese obese patients and correlated positively with the severity of liver steatosis and fibrosis, suggesting that hsCRP can be used as a potential biomarker to monitor and predict disease severity among Chinese obese population with MAFLD.

Associations Between Abdominal Obesity Indices and Nonalcoholic Fatty Liver Disease: Chinese Visceral Adiposity Index

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver metabolic disease worldwide. Up to 70%-80% of patients with NAFLD were obese, especially abdominal obesity. Many indicators of abdominal obesity have been reported, including waist circumference (WC), visceral obesity index (VAI), lipid accumulation (LAP), and Chinese VAI (CVAI). However, few studies investigated the associations between these indices with NAFLD. This present study aims to explore the associations between abdominal obesity indices with NAFLD. A total of 7,238 participants were involved in the cross-sectional study, and 1,584 participants were included in the longitudinal study from Jidong communities. NAFLD was assessed by abdominal ultrasonography. The trajectory of WC, VAI, LAP, and CVAI during 2013-2016 was identified by a group-based trajectory model. The logistic regression and Cox proportional hazards models analyzed the correlations and causality between abdominal obesity indices with NAFLD. In this study, the prevalence and incidence of NAFLD are approximately 44% and 26%, respectively. In the cross-sectional study, WC, VAI, LAP, and CVAI are associated with NAFLD. After adjustment for potential confounders, the moderate-rising and high-rising groups of CVAI had the highest risk of NAFLD in longitudinal analysis (hazard ratio (HR): 3.903, 95%CI: 2.434-6.259; HR: 5.694 95%CI: 3.098-10.464, respectively). Receiving operating characteristic curves show that CVAI has the best diagnostic value for NAFLD (area under the curve (AUC) = 0.868). CVAI is independently associated with the risk of NAFLD and may also have an important value to the diagnosis of NAFLD.

Role of Innate lymphoid Cells in Obesity and Insulin Resistance

Obesity, a growing chronic metabolic disease, greatly increases the risk of metabolic syndrome which includes type 2 diabetes, fatty liver and cardiovascular diseases. Obesity-associated metabolic diseases significantly contribute to mortality and reduce life expectancy. Recently, innate lymphoid cells (ILCs) have emerged as crucial regulators of metabolic homeostasis and tissue inflammation. This review focuses on the roles of ILCs in different metabolic tissues, including adipose tissue, liver, pancreas, and intestine. We briefly outline the relationship between obesity, inflammation, and insulin resistance. We then discuss how ILCs in distinct metabolic organs may function to maintain metabolic homeostasis and contribute to obesity and its associated metabolic diseases. The potential of ILCs as the therapeutic target for obesity and insulin resistance is also addressed.

Anthropometric Indices and Type 2 Diabetes Mellitus as a Risk Factor in Predicting Nonalcoholic Fatty Liver Disease - A Prospective Study in Indian Population

BACKGROUND

The different anthropometric indices have different predictive values of nonalcoholic fatty liver disease (NAFLD) in various populations. Since obesity is a common cause of NAFLD and diabetes, therefore, it is critical to correlate the various anthropometric indices as a risk factor in terms of NAFLD and diabetes in the Indian population. In view of reported association between obesity and NAFLD, the study was employed to analyze the relationship of various anthropometric indices (body mass index [BMI], a body shape index [ABSI], waist-height ratio [WHtR], etc.) with NAFLD and to comment, if possible, which among them has the highest predictive value in patients with type 2 diabetes.

MATERIAL AND METHODS

Data of 220 diabetic patients (36-80 years) were analyzed. Anthropometric data were collected using standard methods. Routine biochemical investigations data were used. Ultrasonography was used to assess liver status for NAFLD.

RESULTS

Based on the results, Waist height ratio [WHtR] and BMI had better correlation with NAFLD than ABSI. The desirable WHtR cutoff value was 0.545 with 62% of sensitivity and 62% of specificity. The cut off for BMI and ABSI were 24.6 and 0.805, respectively, with 65% of sensitivity and 62% of specificity for BMI and 63% of sensitivity and 42% of specificity for ABSI.

CONCLUSION

There is a strong association of BMI and ABSI with NAFLD in this study. Public health measures to limit overnutrition and management of obesity are essential to prevent NAFLD, and as its negative health effects on type 2 diabetes mellitus.

The Perirenal Fat Thickness Was Associated with Nonalcoholic Fatty Liver Disease in Patients with Type 2 Diabetes Mellitus

PURPOSE

Obesity is an important risk factor for nonalcoholic fatty liver disease (NAFLD). Perirenal fat and paranephric fat were seldom studied in NAFLD. We aimed to explore the relationship between perirenal fat thickness (PrFT) and paranephric fat thickness (PnFT) and NAFLD in patients with type 2 diabetes mellitus (T2DM).

PATIENTS AND METHODS

A total of 493 diabetic patients including 231 NAFLD patients were enrolled in our study from September 2019 to December 2020. Patients with NAFLD were categorized into three subgroups according to the severity and fibrosis risk of NAFLD. Anthropometric indices and clinical characteristics were collected from clinical records. PrFT and PnFT were measured via ultrasound. Multivariate logistic regression analysis was used to assess the association between PrFT, PnFT and presence, severity and advanced fibrosis risk of NAFLD.

RESULTS

Compared with non-NAFLD patients, those with NAFLD had significantly higher PrFT and PnFT. The PrFT and PnFT were independently associated with presence of NAFLD and the PrFT was independently associated with the advanced fibrosis risk of NAFLD after adjusting confounding factors.

CONCLUSION

The PrFT was independently associated with the presence and advanced fibrosis risk of NAFLD in patients with T2DM.

The Circadian Clock and Obesity

The modern way of life has dramatically affected our biological rhythms. Circadian rhythms, which are generated by an endogenous circadian clock, are observed in a large number of physiological functions including metabolism. Proper peripheral clock synchronization by different signals including appropriate feeding/fasting cycles is essential to coordinate and temporally gate metabolic processes. In this chapter, we emphasize the importance of nutrient sensing by peripheral clocks and highlight the major role of peripheral and central clock communication to locally regulate metabolic processes and ensure optimal energy storage and expenditure. As a consequence, changes in eating behavior and/or bedtime, as occurs upon shift work and jet lag, have direct consequences on metabolism and participate in the increasing prevalence of obesity and associated metabolic diseases such as type 2 diabetes and non-alcoholic fatty liver disease. In this setting, time-restricted feeding has been suggested as an efficient approach to ameliorate metabolic parameters and control body weight.

Nonalcoholic fatty liver disease is specifically related to the risk of hepatocellular cancer but not extrahepatic malignancies

OBJECTIVE

We performed a matched cohort study among individuals with and without nonalcoholic fatty liver disease (NAFLD) to determine: 1) the incidence of cancers (extrahepatic and liver) and their spectrum and 2) if NAFLD increases the risk of extrahepatic cancers.

METHODS

The NAFLD and non-NAFLD (control) cohorts were identified from electronic medical records via International Classification of Diseases (ICD) codes from a single center and followed from 2010 to 2019. Cohorts were matched 1:2 for age, sex, race, body mass index (BMI), and type 2 diabetes.

RESULTS

A total of 1,412 subjects were included in the analyses. There were 477 individuals with NAFLD and 935 controls (median age, 52 years; women, 54%; white vs. black: 59% vs. 38%; median BMI, 30.4 kg/m²; type 2 diabetes, 34%). The cancer incidence (per 100,000 person-years) was 535 vs. 1,513 (NAFLD vs. control). Liver cancer incidence (per 100,000 person-years) was 89 in the NAFLD group vs. 0 in the control group, whereas the incidence of malignancy was higher across other types of cancer in the control group vs. in the NAFLD group.

CONCLUSIONS

The overall extrahepatic cancer risk in NAFLD is not increased above and beyond the risk from background risk factors such as age, race, sex, BMI, and type 2 diabetes.

A family history of type 2 diabetes as a predictor of fatty liver disease in diabetes-free individuals with excessive body weight

Comprehensive screening for non-alcoholic fatty liver disease (NAFLD) may help prompt clinical management of fatty liver disease. A family history, especially of diabetes, has been little studied as a predictor for NAFLD. We characterized the cross-sectional relationship between a family history of type 2 diabetes (FHT2D) and NAFLD probability in 1185 diabetes-free Apulian (Southern-Italy) subjects aged > 20 years with overweight or obesity not receiving any drug or supplementation. Clinical data and routine biochemistry were analysed. NAFLD probability was defined using the fatty liver index (FLI). A first-degree FHT2D was assessed by interviewing subjects and assigning a score of 0, 1, or 2 if none, only one, or both parents were affected by type 2 diabetes mellitus (T2DM). Our study population featured most females (70.9%, N = 840), and 48.4% (N = 574) of the sample had first-degree FHT2D. After dividing the sample by a FHT2D, we found a higher BMI, Waist Circumference (WC), and diastolic blood pressure shared by FHT2D subjects; they also showed altered key markers of glucose homeostasis, higher triglyceride levels, and worse liver function. FLI scores were significantly lower in subjects without a first-degree FHT2D. After running logistic regression models, a FHT2D was significantly associated with the NAFLD probability, even adjusting for major confounders and stratifying by age (under and over 40 years of age). A FHT2D led to an almost twofold higher probability of NAFLD, regardless of confounding factors (OR 2.17, 95% CI 1.63 to 2.89). A first-degree FHT2D acts as an independent determinant of NAFLD in excess weight phenotypes, regardless of the age group (younger or older than 40 years). A NAFLD risk assessment within multidimensional screening might be useful in excess weight subjects reporting FHT2D even in the absence of diabetes.

CROATIAN GUIDELINES FOR THE DIAGNOSIS AND TREATMENT OF NONALCOHOLIC FATTY LIVER DISEASE

Nonalcoholic fatty liver disease (NAFLD) is a term describing excessive accumulation of fat in hepatocytes, and is associated with metabolic syndrome and insulin resistance. NAFLD prevalence is on increase and goes in parallel with the increasing prevalence of metabolic syndrome and its components. That is why Croatian guidelines have been developed, which cover the screening protocol for patients with NAFLD risk factors, and the recommended diagnostic work-up and treatment of NAFLD patients. NAFLD screening should be done in patients with type 2 diabetes mellitus, or persons with two or more risk factors as part of metabolic screening, and is carried out by noninvasive laboratory and imaging methods used to detect fibrosis. Patient work-up should exclude the existence of other causes of liver injury and determine the stage of fibrosis as the most important factor in disease prognosis. Patients with initial stages of fibrosis continue to be monitored at the primary healthcare level with the management of metabolic risk factors, dietary measures, and increased physical activity. Patients with advanced fibrosis should be referred to a gastroenterologist/hepatologist for further treatment, monitoring, and detection and management of complications.

Nonalcoholic Steatohepatitis Modifies Serum Iron-Related Variables in Patients with Morbid Obesity

Nonalcoholic steatohepatitis (NASH) is frequently associated with severe obesity. The liver is the principal storage repository for iron, and the excessive accumulation of this metal may promote hepatic inflammation. Laparoscopic sleeve gastrectomy (LSG) results in weight loss and improvement in comorbidities such as NASH. The aim of this study was to assess the specific NASH-related changes in iron metabolism and to investigate whether these changes are reversed by LSG. We included 150 patients with morbid obesity who provided 12-h fasting blood samples immediately before LSG together with an intraoperative wedge-liver biopsy. Thirty-eight patients with NASH underwent a second blood extraction 12 months postsurgery. Serum samples were collected from a control group comprising 50 healthy volunteers. We found significantly higher serum iron and transferrin concentrations in patients with NASH along with the highest degrees of steatosis, fibrosis, hepatocellular ballooning, and lobular inflammation. However, we did not find any significant accumulation of iron in the hepatic biopsies. Presurgery serum iron concentrations were lower in the patient group than in the control group and increased 1 year postsurgery. Serum ferritin levels showed changes in the opposite direction. We did not observe any significant change in serum transferrin concentrations. These changes were reversed by LSG. We conclude that alterations in serum iron-related variables are related to the severity of NASH in patients with morbid obesity, and these alterations are reversed by LSG. We also found that severe forms of NASH can be found in the absence of increased iron stores.

Metabolic Effects on Body Components After a Three-Month Physical Intervention in Overweight Medical Staff

Purpose

This study analyzes the metabolic effects on body components of short-term standard physical training interventions in the staff of a Chinese hospital.

Methods and materials

We analyzed annual medical examinations, including blood sampling, ultrasound examinations, etc., and selected 10 overweight voluntary participants to take part in formal physical training, and a body composition analyzer DBA-550 (Donghuayuan Medical Co., Ltd, Beijing, China) was used to analyze body components' change before physical training interventions and the first month and third month after the physical intervention.

Results

The intervention significantly decreased body mass index (BMI) (p<0.05). Plasma lipids, triglyceride, and waist/hip ratio in females, trunk circumference in males, and limb circumference in females changed significantly (p<0.05). The body composition analysis showed that alterations in lean mass, fat weight, and fat percentage were not significant. Moreover, the segmental skeletal weight stable and segmental edema indices changed significantly but were within the normal range.

Conclusions

Three months of short-term physical intervention effectively lower body weight and fat, but more significant changes in long-term intervention and larger groups can be expected. Besides, the body composition analyzer proved reliable and can modify more individualized treatment plans for overweight and obese individuals.

Green Plant Pigment, Chlorophyllin, Ameliorates Non-alcoholic Fatty Liver Diseases (NAFLDs) Through Modulating Gut Microbiome in Mice

Non-alcoholic fatty liver diseases (NAFLDs) along with metabolic syndrome and Type-2 diabetes (T2D) are increasingly prevalent worldwide. Without an effective resolution, simple hepatic steatosis may lead to non-alcoholic steatohepatitis (NASH), characterized by hepatocyte damage, chronic inflammation, necrosis, fatty degeneration, and cirrhosis. The gut microbiome is vital for metabolic homeostasis. Conversely, dysbiosis contributes to metabolic diseases including NAFLD. Specifically, diet composition is critical for the enterotype of gut microbiota. We reasoned that green pigment rich in vegetables may modulate the gut microbiome for metabolic homeostasis. In this study, C57BL/6 mice under a high fat diet (HFD) were treated with sodium copper chlorophyllin (CHL), a water-soluble derivative of chlorophyll, in drinking water. After 28 weeks of HFD feeding, liver steatosis was established accompanied by gut microbiota dysbiosis, intestinal impairment, endotoxemia, systemic inflammation, and insulin resistance. Administration of CHL effectively alleviated systemic and intestinal inflammation and maintained tight junction in the intestinal barrier. CHL rebalanced gut microbiota in the mice under high fat feeding and attenuated hepatic steatosis, insulin resistance, dyslipidemia, and reduced body weight. Fecal flora transplants from the CHL-treated mice ameliorated steatosis as well. Thus, dietary green pigment or the administration of CHL may maintain gut eubiosis and intestinal integrity to attenuate systemic inflammation and relieve NASH.

AMPK/PGC-1α/GLUT4-Mediated Effect of Icariin on Hyperlipidemia-Induced Non-Alcoholic Fatty Liver Disease and Lipid Metabolism Disorder in Mice

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the world. Therapeutic activity of icariin, a major bioactive component of Epimedii Herba, in NAFLD is still unknown. Herein, the C57BL/6J mice were fed with a high-fat diet for 16 weeks to establish a NAFLD model. Mice were assigned to five groups: control group, NAFLD group, and icariin treatment groups. Effects of icariin on blood indices, glucose tolerance, insulin sensitivity, histopathological morphology, cell apoptosis, lipid accumulation, and AMPK signaling were analyzed. In addition, another cohort of mice were assigned to five groups: control group, NAFLD group, dorsomorphin treatment group, icariin treatment group, and dorsomorphin + icariin treatment group. Expression of proteins in liver tissues associated with AMPK signaling, and levels of ALT and AST were evaluated. Icariin attenuated the NAFLD-induced increase of the TG, TC, LDL-C, ALT, AST levels. HDL-C levels were affected neither by NAFLD nor by icariin. Furthermore, icariin treatment (100-200 mg/kg) counteracted the NAFLD-reduced glucose tolerance and insulin sensitivity and modulated histopathological changes, cell apoptosis, and lipid accumulation in liver tissues. Additionally, icariin mitigated the NAFLD-induced up-regulation of the cleaved caspase 3/9, SREBP-1c, and DGAT-2 levels, and enhanced the expression level of CPT-1, p-ACC/ACC, AMPKα1, PGC-1α, and GLUT4. Effects of icariin on the AMPK signaling and levels of AST and ALT could be reversed by AMPK inhibitor, dorsomorphin. This paper investigates the glucose-reducing and lipid-lowering effects of icariin in NAFLD. Moreover, icariin might function through activating the AMPKα1/PGC-1α/GLTU4 pathway.

Association of remnant cholesterol with nonalcoholic fatty liver disease: a general population-based study

BACKGROUND

Remnant cholesterol (RC) mediates the progression of coronary artery disease, diabetic complications, hypertension, and chronic kidney disease. Limited information is available on the association of RC with nonalcoholic fatty liver disease (NAFLD). This study aimed to explore whether RC can be used to independently evaluate the risk of NAFLD in the general population and to analyze the predictive value of RC for NAFLD.

METHODS

The study included 14,251 subjects enrolled in a health screening program. NAFLD was diagnosed by ultrasound, and the association of RC with NAFLD was assessed using the receiver operating characteristic (ROC) curve and logistic regression equation.

RESULTS

Subjects with elevated RC had a significantly higher risk of developing NAFLD after fully adjusting for potential confounding factors (OR 1.77 per SD increase, 95% CI 1.64-1.91, P trend< 0.001). There were significant differences in this association among sex, BMI and age stratification. Compared with men, women were facing a higher risk of RC-related NAFLD. Compared with people with normal BMI, overweight and obesity, the risk of RC-related NAFLD was higher in thin people. In different age stratifications, when RC increased, young people had a higher risk of developing NAFLD than other age groups. Additionally, ROC analysis results showed that among all lipid parameters, the AUC of RC was the largest (women: 0.81; men: 0.74), and the best threshold for predicting NAFLD was 0.54 in women and 0.63 in men.

CONCLUSIONS

The results obtained from this study indicate that (1) in the general population, RC is independently associated with NAFLD but not with other risk factors. (2) Compared with traditional lipid parameters, RC has a better predictive ability for NAFLD in men.

Advances in Unhealthy Nutrition and Circadian Dysregulation in Pathophysiology of NAFLD

Unhealthy diets and lifestyle result in various metabolic conditions including metabolic syndrome and non-alcoholic fatty liver disease (NAFLD). Much evidence indicates that disruption of circadian rhythms contributes to the development and progression of excessive hepatic fat deposition and inflammation, as well as liver fibrosis, a key characteristic of non-steatohepatitis (NASH) or the advanced form of NAFLD. In this review, we emphasize the importance of nutrition as a critical factor in the regulation of circadian clock in the liver. We also focus on the roles of the rhythms of nutrient intake and the composition of diets in the regulation of circadian clocks in the context of controlling hepatic glucose and fat metabolism. We then summarize the effects of unhealthy nutrition and circadian dysregulation on the development of hepatic steatosis and inflammation. A better understanding of how the interplay among nutrition, circadian rhythms, and dysregulated metabolism result in hepatic steatosis and inflammation can help develop improved preventive and/or therapeutic strategies for managing NAFLD.

YiQi YangYin Decoction Attenuates Nonalcoholic Fatty Liver Disease in Type 2 Diabetes Rats

Background

YiQi YangYin Decoction (YQ) is a modern Chinese formula composed by the guidance of traditional Chinese medicine theory, which consists of nine traditional Chinese medicines and is applied to treat type 2 diabetes mellitus (T2DM) with nonalcoholic fatty liver in clinic in China for more than a decade. This study aims to evaluate the antidiabetes and lipid-lowering effect of YQ and explore the possible mechanisms of this action.

Methods

T2DM rat models were established and given YQ at three different doses for three weeks. Tissues, including pancreas islet and liver, and blood serum were collected. The levels of fasting blood glucose (FBG), fasting insulin (Fins), lipid index, such as total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), and low-density lipoprotein (LDL), and hepatic function index such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in serum were measured. Pancreas islet damage and liver damage were observed by hematoxylin and eosin staining. The glycogen content and lipid accumulation in liver were determined by periodic acid-Schiff (PAS) staining and Oil Red O staining. The expression levels of insulin receptor substrate 2 (IRS-2), phosphatidylinositol 3 kinase-associated p85alpha (PI3K p85α), AKT, and Glucose Transporter 2 (Glut4) in pancreas islet and AMP-activated protein kinase alpha (AMPKα), sterol regulatory element-binding protein 1c (SREBP1c), acetyl-CoA carboxylase (ACC1), and peroxisome proliferator-activated receptor-α (PPARα) in liver were determined by western blotting. The relative expressions of ACC1, fatty acid synthase (FAS), stearoyl-CoA desaturase 1 (SCD1), carnitine palmityl transferase-1 (CPT-1), and SREBP-1 mRNA were detected by qRT-PCR.

Results

After administering YiQi for three weeks, the levels of fast blood glucose, fasting insulin, TC, TG, LDL, ALT, AST, and ALP were significantly decreased, while HDL significantly increased compared with the model group. YQ could obviously attenuate pancreatic damage and improve islet α- and ß-cell survival compared with the model group. Furthermore, YQ could attenuate hepatic damage caused by lipid accumulation, decrease the content of lipid, and increase the hepatic glycogen content, compared with the model group. In addition, YQ remarkably elevated the proteins expression of p-PI3K, p-AKT, and GLUT4 in pancreas islet and elevated the proteins expression of p-PI3K, p-AKT, GLUT4, p-AMPK, SREBP1, and PPARα and inhibited the expression of p-ACC1 in liver. Besides, YQ reduced the relative expression of ACC1, FAS, SERBP-1c, and SCD mRNA along with the decreased production of CPT-1 mRNA.

Conclusions

YQ could attenuate type 2 diabetes mellitus by improving islet α- and ß-cells via IRS-2/AKT/GLUT4 pathway and nonalcoholic fatty liver by ameliorating lipid accumulation via AMPK/PPARα/SREBP1/ACC1 pathway.

Superficial vs Deep Subcutaneous Adipose Tissue: Sex-Specific Associations With Hepatic Steatosis and Metabolic Traits

CONTEXT

Subcutaneous adipose tissue (SAT) is not homogeneous, as the fascia scarpa separates the deep SAT (dSAT) from the superficial SAT (sSAT).

OBJECTIVE

The aim of this study is to evaluate the sex-specific associations of sSAT and dSAT with hepatic steatosis and metabolic syndrome in overweight individuals.

METHODS

We recruited 285 individuals with a body mass index (BMI) greater than or equal to 27 and aged 55 to 81 years. Abdominal magnetic resonance imaging was performed around level L4 to L5 to measure visceral adipose tissue (VAT), dSAT, and sSAT volumes. The amount of hepatic fat was quantified by MR spectroscopy.

RESULTS

Men had significantly higher volumes of VAT (122.6 cm3 vs 98.7 cm3, P < .001) and had only half the volume of sSAT compared to women adjusted for BMI (50.3 cm3 in men vs 97.0 cm3 in women, P < .001). dSAT correlated significantly with hepatic fat content in univariate analysis (standardized β = .190, P < .05), while VAT correlated significantly with hepatic steatosis in a multivariate model, adjusted for age, alcohol use, and other abdominal fat compartments (standardized β = .184, P = .037). Moreover, dSAT in men correlated negatively with HDL cholesterol (standardized β = -0.165, P = .038) in multivariate analyses. In women with a BMI between 30 and 40, in a multivariate model adjusted for age, alcohol use, and other abdominal fat compartments, VAT correlated positively (standardized β = -.404, P = .003), and sSAT negatively (standardized β = -.300, P = .04) with hepatic fat content.

CONCLUSION

In men, dSAT is associated with hepatic steatosis and adverse metabolic traits, such as lower HDL cholesterol levels, whereas in women with obesity sSAT shows a beneficial relation with respect to hepatic fat content.

Non-alcoholic Steatohepatitis Pathogenesis, Diagnosis, and Treatment

There has been a rise in the prevalence of non-alcohol fatty liver disease (NAFLD) due to the popularity of western diets and sedentary lifestyles. One quarter of NAFLD patients is diagnosed with non-alcoholic steatohepatitis (NASH), with histological evidence not only of fat accumulation in hepatocytes but also of liver cell injury and death due to long-term inflammation. Severe NASH patients have increased risks of cirrhosis and liver cancer. In this review, we discuss the pathogenesis and current methods of diagnosis for NASH, and current status of drug development for this life-threatening liver disease.

Periodontal disease-related nonalcoholic fatty liver disease and nonalcoholic steatohepatitis: An emerging concept of oral-liver axis

Periodontal disease, a chronic inflammatory disease of the periodontal tissues, is not only a major cause of tooth loss, but it is also known to exacerbate/be associated with various metabolic disorders, such as obesity, diabetes, dyslipidemia, and cardiovascular disease. Recently, growing evidence has suggested that periodontal disease has adverse effects on the pathophysiology of liver disease. In particular, nonalcoholic fatty liver disease, a hepatic manifestation of metabolic syndrome, has been associated with periodontal disease. Nonalcoholic fatty liver disease is characterized by hepatic fat deposition in the absence of a habitual drinking history, viral infections, or autoimmune diseases. A subset of nonalcoholic fatty liver diseases can develop into more severe and progressive forms, namely nonalcoholic steatohepatitis. The latter can lead to cirrhosis and hepatocellular carcinoma, which are end‐stage liver diseases. Extensive research has provided plausible mechanisms to explain how periodontal disease can negatively affect nonalcoholic fatty liver disease and nonalcoholic steatohepatitis, namely via hematogenous or enteral routes. During periodontitis, the liver is under constant exposure to various pathogenic factors that diffuse systemically from the oral cavity, such as bacteria and their by‐products, inflammatory cytokines, and reactive oxygen species, and these can be involved in disease promotion of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. Also, gut microbiome dysbiosis induced by enteral translocation of periodontopathic bacteria may impair gut wall barrier function and promote the transfer of hepatotoxins and enterobacteria to the liver through the enterohepatic circulation. Moreover, in a population with metabolic syndrome, the interaction between periodontitis and systemic conditions related to insulin resistance further strengthens the association with nonalcoholic fatty liver disease. However, most of the pathologic links between periodontitis and nonalcoholic fatty liver disease in humans are provided by epidemiologic observational studies, with the causal relationship not yet being established. Several systematic and meta‐analysis studies also show conflicting results. In addition, the effect of periodontal treatment on nonalcoholic fatty liver disease has hardly been studied. Despite these limitations, the global burden of periodontal disease combined with the recent nonalcoholic fatty liver disease epidemic has important clinical and public health implications. Emerging evidence suggests an association between periodontal disease and liver diseases, and thus we propose the term periodontal disease–related nonalcoholic fatty liver disease or periodontal disease–related nonalcoholic steatohepatitis. Continued efforts in this area will pave the way for new diagnostic and therapeutic approaches based on a periodontologic viewpoint to address this life‐threatening liver disease.

Cardiometabolic Modification of Amyloid Beta in Alzheimer's Disease Pathology

In recent years, several studies have suggested that cardiometabolic disorders, such as diabetes, obesity, hypertension, and dyslipidemia, share strong connections with the onset of neurodegenerative disorders such as Parkinson's and Alzheimer's disease (AD). However, establishing a definitive link between medical disorders with coincident pathophysiologies is difficult due to etiological heterogeneity and underlying comorbidities. For this reason, amyloid β (Aβ), a physiological peptide derived from the sequential proteolysis of amyloid precursor protein (APP), serves as a crucial link that bridges the gap between cardiometabolic and neurodegenerative disorders. Aβ normally regulates neuronal synaptic function and repair; however, the intracellular accumulation of Aβ within the brain has been observed to play a critical role in AD pathology. A portion of Aβ is believed to originate from the brain itself and can readily cross the blood-brain barrier, while the rest resides in peripheral tissues that express APP required for Aβ generation such as the liver, pancreas, kidney, spleen, skin, and lungs. Consequently, numerous organs contribute to the body pool of total circulating Aβ, which can accumulate in the brain and facilitate neurodegeneration. Although the accumulation of Aβ corresponds with the onset of neurodegenerative disorders, the direct function of periphery born Aβ in AD pathophysiology is currently unknown. This review will highlight the contributions of individual cardiometabolic diseases including cardiovascular disease (CVD), type 2 diabetes (T2D), obesity, and non-alcoholic fatty liver disease (NAFLD) in elevating concentrations of circulating Aβ within the brain, as well as discuss the comorbid association of Aβ with AD pathology.

Changes of Carotid Intima-Media Thickness After Sleeve Gastrectomy in High Cardiovascular Risk Patients: a Prospective Study

PURPOSE

There are insufficient data showing the impact of laparoscopic sleeve gastrectomy (LSG) on carotid intima-media thickness (CIMT). Therefore, in the current work, we investigated the improvement of metabolic syndrome and CIMT in patients with obesity after LSG.

METHODS

This study involved 120 consecutively selected Egyptian patients with a high cardiovascular risk who underwent LSG and were followed up for 12 months.

RESULTS

CIMT declined from 0.95 ± 0.17 mm to 0.83 ± 0.12 (p < 0.001) after 12 months. In addition, the mean fasting blood glucose and fasting inulin level dropped significantly from 153.3 ± 63.6 to 108.8 ± 33.8 mg/dl and from 23.1 ± 7.1 mU/ml to 14.1 ± 6.4 respectively (p < 0.001). Furthermore, glycated hemoglobin (HbA1c) declined from 7.02 ± 1.7 to 5.5 ± 0.96 (p < 0.001). At the end of the follow-up period, metabolic parameters such as HOMA-IR, C-reactive protein (CRP), fibrinogen, total cholesterol, LDL cholesterol, triglycerides, AST, and ALT decreased significantly from their respective baselines (p value < 0.001). Moreover, the reduction in CIMT showed a strong positive correlation with the degree of weight loss at 6 months and 12 months of follow-up.

CONCLUSION

LSG led to a substantial decrease in CIMT. Moreover, it significantly impacted cardiovascular risk factors such as obesity, hypertension, insulin resistance, lipid profile, and inflammatory markers.

Increased asprosin is associated with non-alcoholic fatty liver disease in children with obesity

BACKGROUND

Obesity is a common disease among children, often accompanied by a lot of metabolic disease. Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of obesity among children and adolescents. Asprosin has been identified as a new adipokine that is closely associated with hepatic glucose metabolism. However, few data on asprosin in obese children with NAFLD are available. The present study focuses on the relationship between serum asprosin level and NAFLD in children with obesity.

METHODS

A total of 110 subjects (71 boys and 39 girls aged 6-18 years) were recruited from the Second Affiliated Hospital of Xi'an Jiaotong University: 36 obese children with NAFLD, 39 obese children without NAFLD and 35 lean controls. Anthropometric parameters and biochemical data were measured, and the concentrations of asprosin were detected by ELISA.

RESULTS

The levels of serum asprosin were significantly higher in obese children, particularly those with NAFLD and were positively correlated with body mass index, waist to height ratio, fasting blood glucose, alanine aminotransferase and tumor necrosis factor-alpha. Furthermore, asprosin was independently associated with NAFLD in binary logistic regression analysis.

CONCLUSION

Serum asprosin levels were elevated in obese children, especially in those with NAFLD, and were involved in the pathogenesis of NAFLD in children with obesity.

Non-alcoholic fatty liver disease: time for changes

The review contains updated information on the epidemiology, etiology, pathogenesis, diagnosis, treatment and prevention of non-alcoholic fatty liver disease (NAFLD). We searched for terms including NAFLD, non-alcoholic steatohepatitis (NASH), metabolic syndrome and type 2 diabetes mellitus in literature published over the past 5 years using the Scopus, Web of Science, CyberLeninka, PubMed databases. The concept of NAFLD includes two morphological forms of the disease with different prognosis: non-alcoholic fatty hepatosis and NASH. The severity of NASH is quite variable, including fibrosis, cirrhosis and hepatocellular carcinoma. NAFLD, a spectrum of fatty liver disorders of viral, autoimmune, drug-induced, and genetic origin, which are not caused by alcohol abuse, has recently been renamed as metabolic (dysfunction) associated fatty liver disease (MAFLD). The average prevalence of NAFLD is approximately 25% among the adult population worldwide, and in some regions exceeds 30%. An increase in the prevalence of this pathology is in parallel with the global epidemic of obesity and type 2 diabetes mellitus in the world. It is time to reach a general consensus in the scientific community on changing the nomenclature and moving from a negative to a positive definition of NAFLD/NASH. The new nomenclature points to the “positive” determinants of the disease, namely the close relationship with metabolic disorders, instead of defining it as what it is not (ie. non-alcoholic). The MAFLD abbreviation more accurately discloses existing knowledge about fatty liver diseases associated with metabolic dysfunction and should replace NAFLD/NASH, as this will stimulate the research community’s efforts to update the disease nomenclature and subphenotype and accelerate the transition to new treatments. It is important that primary care physicians, endocrinologists, and other specialists are aware of the extent and long-term consequences of NAFLD. Early identification of patients with NASH can help improve treatment outcomes, avoid liver transplantation in patients with decompensated cirrhosis. There are currently no effective treatments for NAFLD, so it is important to follow a multidisciplinary approach, which means using measures to improve prognosis, reduce the risk of death associated with NAFLD, the development of cirrhosis or hepatocellular carcinoma. Epidemiological data suggest a close relationship between unhealthy lifestyles and NAFLD, so lifestyle adjustments are needed to all patients. Insulin sensitizers, statins, ezetimibe, a cholesterol absorption inhibitor, hepatoprotectors, antioxidants, incretin analogues, dipeptidyl peptidase 4 inhibitors, pentoxifylline, probiotics, angiotensin-converting enzyme inhibitors, and endocannabinoid antagonists are used in the treatment of NAFLD.

Application of a Novel Prediction Model for Predicting 2-Year Risk of Non-Alcoholic Fatty Liver Disease in the Non-Obese Population with Normal Blood Lipid Levels: A Large Prospective Cohort Study from China

Purpose

The purpose of this study was to develop and validate a nomogram to better assess the 2-year risk of non-alcoholic fatty liver disease (NAFLD) in non-obese population with normal blood lipid levels.

Patients and Methods

This study was a secondary analysis of a prospective study. We included 3659 non-obese adults with normal blood lipid levels without NAFLD at baseline. A total of 2744 participants were included in the development cohort and 915 participants were included in the validation cohort. The least absolute contraction selection operator (LASSO) regression model was used to identify the best risk factors. Multivariate Cox regression analysis was used to construct the prediction model. The performance of the prediction model was assessed using Harrell’s consistency index (C-index), area under the receiver operating characteristic (AUROC) curve and calibration curve. Decision curve analysis was applied to evaluate the clinical usefulness of the prediction model.

Results

After LASSO regression analysis and multivariate Cox regression analysis on the development cohort, BMI, TG, DBIL, ALT and GGT were found to be risk predictors and were integrated into the nomogram. The C-index of development cohort and validation cohort was 0.819 (95% CI, 0.798 to 0.840) and 0.815 (95% CI, 0.781 to 0.849), respectively. The AUROC of 2-year NAFLD risk in the development cohort and validation cohort was 0.831 (95% CI, 0.811 to 0.851) and 0.797 (95% CI, 0.765 to 0.829), respectively. From calibration curves, the nomogram showed a good agreement between predicted and actual probabilities. The decision curve analysis indicated that application of the nomogram is more effective than the intervention-for-all-patients scheme.

Conclusion

We developed and validated a nomogram for predicting 2-year risk of NAFLD in the non-obese population with normal blood lipid levels.

Role of Glucagon-Like Peptide-1 Receptor Agonists in the Management of Non-Alcoholic Steatohepatitis: A Clinical Review Article

Non-alcoholic fatty liver disease (NAFLD) has emerged as one of the lethal causes of chronic liver disease globally. NAFLD can ultimately progress to non-alcoholic steatohepatitis (NASH) given persistent cellular insult. The crux of the problem lies in fat accumulation in the liver, such as increased fatty acid substrates owing to consumption of a high-fat diet, altered gut physiology, and excess adipose tissue. Being the hepatic manifestation of metabolic syndrome, insulin resistance is also among one of the many stimuli. Therefore, drugs, such as glucagon-like peptide-1 receptor agonist (GLP-1 RA) can play a significant role in reducing inflammation, in addition to weight loss and dietary habits. In this review article, we have reviewed the role of exenatide, liraglutide, and semaglutide in the management of NASH. Two of the agents, exenatide and semaglutide, have a predominant role in reducing alanine aminotransferase (ALT) levels, therefore reducing inflammation and promoting weight loss. However, these agents have a lesser impact on the degree of fibrosis. Liraglutide, on the other hand, has been shown to significantly decrease the degree of fibrosis and has been found helpful in reversing mild degrees of steatosis. Therefore, these agents warrant attention to the new perspective that has been presented so that future guidelines may incorporate and streamline individualized therapy.

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.

Anti-obesity properties and mechanism of action of flavonoids: A review

Obesity is a major public health problem, and there is increasing scientific interest in its mechanisms, as well as a search for new compounds with antioxidant and anti-inflammatory properties that can minimize the metabolic complications associated with its pathology. One potential source of these compounds is natural products; Among these, flavonoids are a promising group of natural substances. Flavonoids are active constituents with diverse biological activities and are widely found in plants kingdom. Numerous studies have shown that flavonoids can effectively inhibit obesity and related metabolic disorders. The review synthesizes recent evidence in respect of progress in the understanding of the anti-obesity effects of flavonoids. Such effects which occurs through the modulation of proteins, genes and transcriptional factors involved in decreasing lipogenesis, increasing lipolysis, expenditure energy, stimulating fatty acids B-oxidation, digestion and metabolism of carbohydrates. In addition to mitigating inflammatory responses and suppress oxidative stress. A better understanding of the modulating effects and mechanisms of flavonoids in relation to obesity will allow us to better use these compounds to treat or even prevent obesity and its associated comorbidities.

Obese Animals as Models for Numerous Diseases: Advantages and Applications

With the advances in obesity research, a variety of animal models have been developed to investigate obesity pathogenesis, development, therapies and complications. Such obese animals would not only allow us to explore obesity but would also represent models to study diseases and conditions that develop with obesity or where obesity represents a risk factor. Indeed, obese subjects, as well as animal models of obesity, develop pathologies such as cardiovascular diseases, diabetes, inflammation and metabolic disorders. Therefore, obese animals would represent models for numerous diseases. Although those diseases can be induced in animals by chemicals or drugs without obesity development, having them developed as consequences of obesity has numerous advantages. These advantages include mimicking natural pathogenesis processes, using diversity in obesity models (diet, animal species) to study the related variabilities and exploring disease intensity and reversibility depending on obesity development and treatments. Importantly, therapeutic implications and pharmacological tests represent key advantages too. On the other hand, obesity prevalence is continuously increasing, and, therefore, the likelihood of having a patient suffering simultaneously from obesity and a particular disease is increasing. Thus, studying diverse diseases in obese animals (either induced naturally or developed) would allow researchers to build a library of data related to the patterns or specificities of obese patients within the context of pathologies. This may lead to a new branch of medicine specifically dedicated to the diseases and care of obese patients, similar to geriatric medicine, which focuses on the elderly population.

Leaf powder supplementation of Senna alexandrina ameliorates oxidative stress, inflammation, and hepatic steatosis in high-fat diet-fed obese rats

Obesity is an enduring medical issue that has raised concerns around the world. Natural plant extracts have shown therapeutic potential in preventing oxidative stress and inflammation related to obesity complications. In this study, Senna alexandrina Mill. leaves were utilized to treat high-fat diet-related metabolic disorders and non-alcoholic fatty liver diseases. Plasma biochemical assays were conducted to determine the lipid profiles and oxidative stress parameters, and the gene expression of antioxidant enzymes and inflammatory mediators was measured. Histological stained livers of high-fat diet-fed rats were observed. S. alexandrina leaf powder supplementation prevented the increase in cholesterol and triglyceride levels in high-fat diet-fed rats. Moreover, S. alexandrina leaves also reduced lipid peroxidation and nitric oxide production in these rats. Prevention of oxidative stress by S. alexandrina leaf supplementation in high-fat diet-fed rats is regulated by enhancing the antioxidant enzyme activity, followed by the restoration of corresponding gene expressions, such as NRF-2, HO-1, SOD, and CAT. Histological staining provides further evidence that S. alexandrina leaf supplementation prevents inflammatory cell infiltration, lipid droplet deposition, and fibrosis in the liver of high-fat diet-fed rats. Furthermore, this investigation revealed that S. alexandrina leaf supplementation controlled non-alcoholic fatty liver disease by modulating the expression of fat metabolizing enzymes in high-fat diet-fed rats. Therefore, S. alexandrina leaf supplementation inhibits fatty liver inflammation and fibrosis, suggesting its usefulness in treating non-alcoholic steatohepatitis. Thus, this natural leaf extract has potential in treatment of obesity related liver dysfunction.

Non Alcoholic Fatty Liver Disease Is Positively Associated with Increased Glycated Haemoglobin Levels in Subjects without Diabetes

Screening for non-alcoholic fatty liver disease (NAFLD) is key step for primary management of fatty liver in the clinical setting. Excess weight subjects carry a greater metabolic risk even before exhibiting pathological patterns, including diabetes. We characterized the cross-sectional relationship between routine circulating biomarkers and NAFLD in a large sample of diabetes-free subjects with overweight or obesity, to elucidate any independent relationship. A population sample of 1232 consecutive subjects with a body mass index of at least 25 kg/m2, not receiving any drug or supplemental therapy, was studied. Clinical data and routine biochemistry were analyzed. NAFLD was defined using the validated fatty liver index (FLI), classifying subjects with a score ≥ 60% as at high risk. Due to extreme skewing of variables of interest, resampling matching for age and sex was performed. Our study population was characterized by a majority of females (69.90%) and a prevalence of NAFLD in males (88.90%). As a first step, propensity score matching was explicitly performed to balance the two groups according to the FLI cut-off. Based on the resulting statistical trajectories, corroborated even after data matching, we built two logistic regression models on the matched population (N = 732) to verify any independent association. We found that each unit increase of FT3 implicated a 50% increased risk of NAFLD (OR 1.506, 95%CI 1.064 to 2.131). When including glycated haemoglobin (HbA1c) in the model, free-triiodothyronine (FT3) lost significance (OR 1.557, 95%CI 0.784 to 3.089) while each unit increase in HbA1c (%) indicated a significantly greater NAFLD risk, by almost two-fold (OR 2.32, 95%CI 1.193 to 4.512). Glucose metabolism dominates a key pathway along the hazard trajectories of NAFLD, turned out to be key biomarker in monitoring the risk of fatty liver in diabetes-free overweight subjects. Each unit increase in HbA1c (%) indicated a significantly greater NAFLD risk, by almost two-fold, in our study.

Changes in Plasma Growth Differentiation Factor-15 After Laparoscopic Sleeve Gastrectomy in Morbidly Obese Patients: A Prospective Study

PURPOSE

This study aimed to assess the potential changes of Growth differentiation factor 15 (GDF15) after laparoscopic sleeve gastrectomy (LSG) in morbidly obese patients.

METHODS

We conducted a prospective study on 68 patients who underwent LSG and 58 cases, who were enrolled as a control group, to whom conservative measures of weight loss were adopted. Both groups were followed for 12 months.

RESULTS

At the baseline, the serum GDF15 was comparable between LSG and conservative groups (409.93±119 versus 385.8±120.2 pg/mL, p =0.246). However, at 12 months after the operation, the serum GDF15 was significantly higher in the LSG than conservative groups (699.941 ±193.5 versus 559 ±159.7; p <0.001). The degree of serum GDF15 increase was higher in the LSG group (290.01 ±189.9 versus 173.14 ±116.7; p <0.001). The degree of serum GDF15 increase correlated negatively with the final BMI (r = -0.352, p =0.001) and weight loss (r = -0.793, p =0.001) at 12 months after the operation. The correlation analysis demonstrated that the initial GFD15 did not correlate with any baseline parameters. Multiple regression analysis of change in serum GDF15 showed a statistical significance of the weight loss after 12 months.

CONCLUSION

The present work confirms the impact of successful weight loss on the circulating level of GDF15. Our study demonstrated that the circulating GDF15 increased significantly after LSG and it was correlated to the degree of weight loss.

Higher plain water intake is related to lower newly diagnosed nonalcoholic fatty liver disease risk: a population-based study

BACKGROUND/OBJECTIVES

High plain water intake (PWI) lowered body weight, reduced total energy intake, and increased fat oxidation and energy consumption. Because such factors are closely linked to metabolic disorders, which are the main risk factors for nonalcoholic fatty liver disease (NAFLD) onset, it was speculated that higher PWI was associated with a lower risk of NAFLD. However, no prior human studies have examined such relationship. Therefore, the purpose of this study was to evaluate the relationship between PWI and newly diagnosed NAFLD in a large-scale adult population.

SUBJECTS/METHODS

A total of 16,434 participants from 2010 to 2019 in Tianjin, China, were included in this cross-sectional study. PWI was assessed by using a validated self-administered food frequency questionnaire, and it was categorized into three subgroups for analysis: ≤3 cups/day, 4-7 cups/day, and >7 cups/day. NAFLD was diagnosed by abdominal ultrasound. Logistic regression analysis was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for the relationship between PWI and NAFLD.

RESULTS

Among 16,434 participants, 20.5% (3,364) had newly diagnosed NAFLD. After controlling for demographic characteristics, lifestyle risk factors, and dietary intake, the adjusted ORs (95% CIs) for having NAFLD across PWI categories were 1.00 (reference) for ≤3 cups/day, 0.84 (0.72, 0.97) for 4-7 cups/day, and 0.77 (0.63, 0.94) for >7 cups/day in males and 1.00 (reference) for ≤3 cups/day, 1.02 (0.81, 1.27) for 4-7 cups/day, and 1.08 (0.78, 1.49) for >7 cups/day in females, respectively.

CONCLUSIONS

This study is the first to show that higher PWI is independently related to lower newly diagnosed NAFLD among males, but not females. Further studies are needed to explore the causal relationship.

Fenofibrate Regulates Visceral Obesity and Nonalcoholic Steatohepatitis in Obese Female Ovariectomized C57BL/6J Mice

Fibrates, including fenofibrate, are a class of hypolipidemic drugs that activate peroxisome proliferator-activated receptor α (PPARα), which in-turn regulates the expression of lipid and lipoprotein metabolism genes. We investigated whether fenofibrate can reduce visceral obesity and nonalcoholic fatty liver disease via adipose tissue PPARα activation in female ovariectomized (OVX) C57BL/6J mice fed a high-fat diet (HFD), a mouse model of obese postmenopausal women. Fenofibrate reduced body weight gain (-38%, p < 0.05), visceral adipose tissue mass (-46%, p < 0.05), and visceral adipocyte size (-20%, p < 0.05) in HFD-fed obese OVX mice. In addition, plasma levels of alanine aminotransferase and aspartate aminotransferase, as well as free fatty acids, triglycerides, and total cholesterol, were decreased. Fenofibrate also inhibited hepatic lipid accumulation (-69%, p < 0.05) and infiltration of macrophages (-72%, p < 0.05), while concomitantly upregulating the expression of fatty acid β-oxidation genes targeted by PPARα and decreasing macrophage infiltration and mRNA expression of inflammatory factors in visceral adipose tissue. These results suggest that fenofibrate inhibits visceral obesity, as well as hepatic steatosis and inflammation, in part through visceral adipose tissue PPARα activation in obese female OVX mice.

Assessment of the association between body composition and risk of non-alcoholic fatty liver

Non-alcoholic fatty liver disease (NAFLD) is defined as the condition of fat accumulation in the liver. This cross-sectional study aimed to investigate the relationship between body composition and fatty liver and determine of cut-off point for predicting NAFLD. Samples were selected from the nutrition clinic from 2016 to 2017 in Tehran, Iran. The liver steatosis was calculated using the CAP score through the FiroScan^™ and body composition was measured using the dual-energy X-ray absorptiometry scan method. A total of 2160 patients participated in this study, 745 (34.5%) subjects had NAFLD. We found that fat-free tissue was inversely and fat tissue was directly correlated with the risk of NAFLD in almost all factors and the risk of developing NAFLD increases if the total fat exceeds 32.23% and 26.73% in women and men and abdominal fat exceeds 21.42% and 13.76% in women and men, respectively. Finally, we realized that the total fat percent had the highest AUC (0.932 for men and 0.917 for women) to predict the risk of NAFLD. Overall, the likelihood of NAFLD development rose significantly with increasing the amount of total fat and abdominal fat from the cut-off point level.

Dietary Polyphenols to Combat Nonalcoholic Fatty Liver Disease via the Gut-Brain-Liver Axis: A Review of Possible Mechanisms

Polyphenols are a group of micronutrients widely existing in plant foods including fruits, vegetables, and teas that can improve nonalcoholic fatty liver disease (NAFLD). In this review, the existing knowledge of dietary polyphenols for the development of NAFLD regulated by intestinal microecology is discussed. Polyphenols can influence the vagal afferent pathway in the central and enteric nervous system to control NAFLD via gut-brain-liver cross-talk. The possible mechanisms involve in the alteration of microbial community structure, effects of gut metabolites (short-chain fatty acids (SCFAs), bile acids (BAs), endogenous ethanol (EnEth)), and stimulation of gut-derived hormones (ghrelin, cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), and leptin) based on the targets excavated from the gut-brain-liver axis. Consequently, the communication among the intestine, brain, and liver paves the way for new approaches to understand the underlying roles and mechanisms of dietary polyphenols in NAFLD pathology.

Tracking biochemical changes induced by iron loading in AML12 cells with synchrotron live cell, time-lapse infrared microscopy

Hepatocytes are essential for maintaining the homeostasis of iron and lipid metabolism in mammals. Dysregulation of either iron or lipids has been linked with serious health consequences, including non-alcoholic fatty liver disease (NAFLD). Considered the hepatic manifestation of metabolic syndrome, NAFLD is characterised by dysregulated lipid metabolism leading to a lipid storage phenotype. Mild to moderate increases in hepatic iron have been observed in ∼30% of individuals with NAFLD; however, direct observation of the mechanism behind this increase has remained elusive. To address this issue, we sought to determine the metabolic consequences of iron loading on cellular metabolism using live cell, time-lapse Fourier transform infrared (FTIR) microscopy utilising a synchrotron radiation source to track biochemical changes. The use of synchrotron FTIR is non-destructive and label-free, and allowed observation of spatially resolved, sub-cellular biochemical changes over a period of 8 h. Using this approach, we have demonstrated that iron loading in AML12 cells induced perturbation of lipid metabolism congruent with steatosis development. Iron-loaded cells had approximately three times higher relative ester carbonyl concentration compared with controls, indicating an accumulation of triglycerides. The methylene/methyl ratio qualitatively suggests the acyl chain length of fatty acids in iron-loaded cells increased over the 8 h period of monitoring compared with a reduction observed in the control cells. Our findings provide direct evidence that mild to moderate iron loading in hepatocytes drives de novo lipid synthesis, consistent with a role for iron in the initial hepatic lipid accumulation that leads to the development of hepatic steatosis.

Effect of Different Exercise Intensities on Hepatocyte Apoptosis in HFD-Induced NAFLD in Rats: The Possible Role of Endoplasmic Reticulum Stress through the Regulation of the IRE1/JNK and eIF2α/CHOP Signal Pathways

OBJECTIVE

To investigate the impact of different-intensity exercise on lipid metabolism, oxidative stress, hepatocyte injury, and apoptosis and the related protein expression of endoplasmic reticulum stress on nonalcoholic fatty liver disease rats.

METHOD

50 male Sprague-Dawley rats, 2 months old, were randomly divided into the normal control (CON) group, high-fat diet (HFD) group, low-intensity exercise (LIE) group, moderate-intensity exercise (MIE) group, and incremental-intensity exercise (IIE) group. Blood lipids were tested by the automatic biochemical analyzer. The changes in liver tissues were observed by hematoxylin-eosin staining (HE). The protein expression of Bax and Bcl-2 was detected by the immunohistochemical method. The apoptosis of hepatocytes was detected by the TUNEL method. The protein expression of GRP78, Caspase-3, IRE1, p-IRE1, JNK1, CHOP, PERK, eIF2α, and ATF4 was detected by Western blotting.

RESULTS

Our study showed that compared with the HFD group, TG, TC, FFA, and LDL-c were reduced in all exercise groups. The different exercise intensities could reduce the protein expression of ATF4, Bax, and hepatocyte apoptosis. Meanwhile, the antioxidant function and Bcl-2 were increased. However, the moderate-intensity exercise demonstrated more effect on improving the antioxidant capacity and inhibiting hepatocyte apoptosis. Compared with the HFD group, Caspase-3 and JNK were significantly decreased in all exercise groups (P < 0.01) and CHOP was decreased in the LIE and MIE groups (P < 0.05). IRE1, eIF2α, the ratio of p-IRE1/IRE1 (P < 0.01), and ATF4 were decreased (P < 0.05) in the MIE group. Compared with the IIE group, p-IRE1 was decreased (P < 0.05) in the MIE group. GRP78 had no significant difference among the exercise groups.

CONCLUSION

Exercise at different intensities improved blood lipid and hepatic injury in NAFLD rats. However, the body weight of the rats in each exercise group was not significantly different. Moderate-intensity exercise demonstrated more effect on improving the antioxidant ability and inhibiting hepatocyte apoptosis. The possible mechanism depends on the regulation of endoplasmic reticulum stress signaling pathways IRE1/JNK and eIF2α/CHOP.