Insulin resistance: a metabolic pathway to chronic liver disease

Metabolic dysfunction-associated steatotic liver disease and diabetes: the cross-talk between hepatologist and diabetologist

INTRODUCTION

Metabolic dysfunction-associated steatotic liver disease (MASLD) and type 2 diabetes mellitus (DM) are the most prevalent metabolic disorders globally. The numbers affected in both disorders are also rapidly increasing with alarming trends in children and young adults.

AREAS COVERED

Insulin resistance (IR) and the subsequent metabolic dysregulation are the fundamental pathogenesis pathways of the prevalent metabolic disorders. The interaction and impacts are bidirectional between MASLD and DM in terms of disease mechanisms, disease course, risks, and prognosis. There's a pressing issue for highlighting the links between MASLD and DM for both care specialists as well as primary care providers. The review collected the scientific evidence addressing the mutual interactions between the two disorders. The strategies for surveillance, risk stratification, and management are discussed in a practical manner. It also provides individualized viewpoints of patient care in hepatology and diabetology.

EXPERT OPINION

Both MASLD and DM shared similar disease mechanisms, and affected the disease development and progression in a bidirectional manner. The high prevalence and the cross-link between the two disorders raise clinical issues from awareness, screening, risk stratification, optimal referral, to appropriate management for primary care providers.

Chitosan-modified dihydromyricetin liposomes promote the repair of liver injury in mice suffering from diabetes mellitus

Liver injury caused by type-II diabetes mellitus (DM) is a significant public-health concern worldwide. We used chitosan (CS) to modify dihydromyricetin (DHM)-loaded liposomes (DL) through charge interaction. The effect of CS-modified DL (CDL) on liver injury in mice suffering from DM was investigated in vivo and in vitro. CDL exhibited superior antioxidant capacity and stability. Pharmacokinetic analyses revealed a 3.23- and 1.92-fold increase in the drug concentration-time curve (953.60 ± 122.55 ng/mL/h) in the CDL-treated group as opposed to the DHM-treated group (295.15 ± 25.53 ng/mL/h) and DL-treated group (495.31 ± 65.21 ng/mL/h). The maximum drug concentration in blood (Tmax) of the CDL group saw a 2.26- and 1.21-fold increase compared with that in DHM and DL groups. We observed a 1.49- and 1.31-fold increase in the maximum drug concentration in blood (Cmax) in the CDL group compared with that in DHM and DL groups. Western blotting suggested that CDL could alleviate liver injury in mice suffering from DM by modulating inflammatory factors and the transforming growth factor-β1/Smad2/Smad3 signaling pathway. In conclusion, modification of liposomes using CS is a viable approach to address the limitations of conventional liposomes and insoluble drugs.

Aging promotes metabolic dysfunction-associated steatotic liver disease by inducing ferroptotic stress

Susceptibility to the biological consequences of aging varies among organs and individuals. We analyzed hepatocyte transcriptomes of healthy young and aged male mice to generate an aging hepatocyte gene signature, used it to deconvolute transcriptomic data from humans and mice with metabolic dysfunction-associated liver disease, validated findings with functional studies in mice and applied the signature to transcriptomic data from other organs to determine whether aging-sensitive degenerative mechanisms are conserved. We discovered that the signature enriches in diseased livers in parallel with degeneration. It is also enriched in failing human hearts, diseased kidneys and pancreatic islets from individuals with diabetes. The signature includes genes that control ferroptosis. Aged mice develop more hepatocyte ferroptosis and liver degeneration than young mice when fed diets that induce metabolic stress. Inhibiting ferroptosis shifts the liver transcriptome of old mice toward that of young mice and reverses aging-exacerbated liver damage, identifying ferroptosis as a tractable, conserved mechanism for aging-related tissue degeneration.

Triglyceride-glucose-alanine aminotransferase index: A noninvasive serum predictor for identifying the severity of pediatric nonalcoholic fatty liver disease

We hypothesized that the triglyceride-glucose (TyG)-alanine aminotransferase (ALT) index, which combines the TyG index with ALT, may enhance sensitivity and specificity in detecting the severity of nonalcoholic fatty liver disease (NAFLD). A total of 131 NAFLD patients with a mean age of 11.5 ± 2.29 years were enrolled, and severity was assessed by ultrasound fatty liver index (US-FLI) scoring. The TyG-ALT index was defined as ln(fasting triglyceride [mg/dL] × fasting glucose [mg/dL] × ALT [IU/L]/2). Multiple linear regression analysis revealed a significant association between the TyG-ALT index and US-FLI (β = 0.317, P < .001) after controlling for sex, age, and body mass index. The TyG-ALT index showed a more stable and superior ability to detect the severity of NAFLD compared to both ALT and the TyG index. The area under the curve values, listed in the order of ALT, TyG index, and TyG-ALT index, were as follows: 0.737 (P < .001), 0.599 (P = .055), and 0.704 (P < .001) at US-FLI ≥ 4 points; 0.717 (P < .001), 0.720 (P < .001), and 0.775 (P < .001) at US-FLI ≥ 5 points; and 0.689 (P < .05), 0.748 (P < .01), and 0.775 (P < .001) at US-FLI ≥ 6 points. The TyG-ALT index is associated with US-FLI score and superior to both ALT and the TyG index in predicting NAFLD severity. These findings indicate the potential of the TyG-ALT index in the management of pediatric NAFLD progression.

A Healthful Plant-Based Diet as an Alternative Dietary Approach in the Management of Metabolic Dysfunction-Associated Steatotic Liver Disease

Plant-based diets (PBDs) are gaining attention as a sustainable and health-conscious alternative for managing various chronic conditions, including metabolic dysfunction-associated steatotic liver disease (MASLD). In the absence of pharmacological treatments, exploring the potential of lifestyle modifications to improve biochemical and pathological outcomes becomes crucial. The adoption of PBDs has demonstrated beneficial effects such as weight control, increased metabolic health and improved coexisting diseases. Nonetheless, challenges persist, including adherence difficulties, ensuring nutritional adequacy, and addressing potential deficiencies. The aim of this review is to provide a comprehensive overview of the impact of PBDs on MASLD, emphasizing the need for tailored dietary interventions with professional support to optimize their effectiveness in preventing and treating metabolic diseases.

Association between the cardiometabolic index and NAFLD and fibrosis

Composed of obesity and lipid parameters, the cardiometabolic index (CMI) has emerged as a novel diagnostic tool. Originally developed for diabetes diagnosis, its application has expanded to identifying patients with cardiovascular diseases, such as atherosclerosis and hypertension. However, the relationship between CMI and non-alcoholic fatty liver disease (NAFLD) and liver fibrosis in the US population remains unclear. This cross-sectional study analyzed data from the National Health and Nutrition Examination Survey (NHANES) spanning 2017-2020, involving 2996 participants aged 20 years or older. Vibration controlled transient elastography using a FibroScan® system (model 502, V2 Touch) with controlled attenuation parameter measurements identified NAFLD at a threshold of ≥ 274 dB/m, while liver stiffness measurement (LSM) results (median, ≥ 8.2 kPa) indicated fibrosis. A multifactorial logistic regression model explored the relationship between CMI and NAFLD and fibrosis. The effectiveness of CMI in detecting NAFLD and liver fibrosis was assessed through receiver operating characteristic curve analysis. Controlling for potential confounders, CMI showed a significant positive association with NAFLD (adjusted OR = 1.44, 95% CI 1.44-1.45) and liver fibrosis (adjusted OR = 1.84, 95% CI 1.84-1.85). The Areas Under the Curve for predicting NAFLD and fibrosis were 0.762 (95% CI 0.745 ~ 0.779) and 0.664(95% CI 0.633 ~ 0.696), respectively, with optimal cut-off values of 0.462 and 0.527. There is a positive correlation between CMI and NAFLD and fibrosis, which is a suitable and simple predictor of NAFLD and fibrosis.

Positive Effects of Physical Activity on Insulin Signaling

Physical activity is integral to metabolic health, particularly in addressing insulin resistance and related disorders such as type 2 diabetes mellitus (T2DM). Studies consistently demonstrate a strong association between physical activity levels and insulin sensitivity. Regular exercise interventions were shown to significantly improve glycemic control, highlighting exercise as a recommended therapeutic strategy for reducing insulin resistance. Physical inactivity is closely linked to islet cell insufficiency, exacerbating insulin resistance through various pathways including ER stress, mitochondrial dysfunction, oxidative stress, and inflammation. Conversely, physical training and exercise preserve and restore islet function, enhancing peripheral insulin sensitivity. Exercise interventions stimulate β-cell proliferation through increased circulating levels of growth factors, further emphasizing its role in maintaining pancreatic health and glucose metabolism. Furthermore, sedentary lifestyles contribute to elevated oxidative stress levels and ceramide production, impairing insulin signaling and glucose metabolism. Regular exercise induces anti-inflammatory responses, enhances antioxidant defenses, and promotes mitochondrial function, thereby improving insulin sensitivity and metabolic efficiency. Encouraging individuals to adopt active lifestyles and engage in regular exercise is crucial for preventing and managing insulin resistance and related metabolic disorders, ultimately promoting overall health and well-being.

Associations of four surrogate insulin resistance indexes with non-alcoholic steatohepatitis in Chinese patients with obesity: a cross-sectional study

OBJECTIVES

This study was designed to evaluate the association of four surrogate indexes of IR with NASH in patients with obesity.

METHODS

A total of 270 patients who underwent bariatric surgery, were included in this cross-sectional study. NASH was diagnosed based on liver biopsies. Binary logistics regression analyses were performed to assess the associations of four surrogate indexes of IR (HOMA-IR, Matsuda index, TyG, and TG/HDL-C) with NASH in patients with obesity. The restricted cubic spline was used to assess the dose-response associations of surrogate indexes of IR with NASH after adjusting for confounding factors.

RESULTS

NASH was diagnosed in 136 patients, with a prevalence of 50.37%. Compared with tertile 1, the fully adjusted ORs (95% CIs) of NASH for tertile 3 were 2.711(1.113-6.608) and 0.297 (0.152-0.579) for TyG and Matsuda index. Consistently, per SD increment of TyG were still significantly associated with 64% increased risks of NASH, and per SD increment of Matsuda index were still significantly associated with 38% decreased risks of NASH. In contrast, no significant associations were found between HOMA-IR and TG/HDL-C and the risk of NASH in patients with obesity (all P > 0.05). After adjusting covariates in restricted cubic splines, the risk of NASH decreased with the increment of Matsuda Index levels (P-nonlinear = 0.442, P-overall = 0.007) and with the decrement of TyG levels (P-nonlinear = 0.004, P-overall = 0.001).

CONCLUSIONS

In patients with obesity, TyG and Matsuda index were independently related to the risk of NASH after adjustment for traditional risk factors. In addition, compared with HOMA-IR and TG/HDL-C, the Matsuda index and TyG may be more suitable for NASH prediction in patients with obesity.

Harnessing Metabolic Indices as a Predictive Tool for Cardiovascular Disease in a Korean Population without Known Major Cardiovascular Event

BACKGRUOUND

This study evaluated the usefulness of indices for metabolic syndrome, non-alcoholic fatty liver disease (NAFLD), and insulin resistance (IR), as predictive tools for cardiovascular disease in middle-aged Korean adults.

METHODS

The prospective data obtained from the Ansan-Ansung cohort database, excluding patients with major adverse cardiac and cerebrovascular events (MACCE). The primary outcome was the incidence of MACCE during the follow-up period.

RESULTS

A total of 9,337 patients were included in the analysis, of whom 1,130 (12.1%) experienced MACCE during a median follow-up period of 15.5 years. The metabolic syndrome severity Z-score, metabolic syndrome severity score, hepatic steatosis index, and NAFLD liver fat score were found to significantly predict MACCE at values above the cut-off point and in the second and third tertiles. Among these indices, the hazard ratios of the metabolic syndrome severity score and metabolic syndrome severity Z-score were the highest after adjusting for confounding factors. The area under the receiver operating characteristic curve (AUC) of the 10-year atherosclerotic cardiovascular disease (ASCVD) score for predicting MACCE was 0.716, and the metabolic syndrome severity Z-score had an AUC of 0.619.

CONCLUSION

The metabolic syndrome severity score is a highly reliable indicator and was closely associated with the 10-year ASCVD risk score in predicting MACCE in the general population. Given the specific characteristics and limitations of metabolic syndrome severity scores as well as the indices of NAFLD and IR, a more practical scoring system that considers these factors is essential to achieve greater accuracy in forecasting cardiovascular outcomes.

Association Between Insulin Resistance Indices and Liver Function Parameters Among Women With Polycystic Ovary Syndrome

OBJECTIVE

This study aimed to investigate whether polycystic ovary syndrome (PCOS) status changes the association between insulin resistance (IR) indices and liver function parameters among women.

METHODS

This is a cross-sectional, population-based study. We selected 1101 subjects aged ≥20 years from participants of Tehran Lipid and Glucose Study (TLGS). All of them had known the status of PCOS, and all variables were related to the IR indices and liver function parameters. The main outcome measures were TG/HDL-C and triglyceride-glucose (TyG) and liver function parameters (hepatic steatosis index [HSI], alanine transaminase [ALT] and aspartate transaminase [AST]).

RESULT

In the present study, there was no significant difference between the PCOS and the non-PCOS regarding the presence of liver function abnormalities. A model adjusted by age and BMI showed that the upper tertile of TyG index was positively associated with high AST (OR = 3.04 [95% CI: 1.20-7.68], p < 0.05), high ALT (4.76 [3.07-7.36], p < 0.05) and high HSI (8.44 [1.82-39.17], p < 0.05). Although the history of diabetes had a positive impact on elevated AST (1.66 [1.15, 2.40], p < 0.05), the third tertile of TG/HDL-C was associated with increased odds of elevated ALT (3.35 [2.21-5.06]) and HSI (6.55 [1.17-36.46]), whereas the second tertile of TG/HDL-C (OR = 2.65, CI 95%: 1.74-4.03) was also positively associated with elevated ALT. PCOS had no significant association with elevated liver function tests.

CONCLUSION

The highest tertile of TyG index and the TG/HDL-C ratio as a surrogate of IR might play a role in detecting abnormalities of liver function parameters among women. However, PCOS status cannot change the association between IR and liver dysfunction.

Assessing the predictive value of insulin resistance indices for metabolic syndrome risk in type 2 diabetes mellitus patients

Limited research has explored the effectiveness of insulin resistance (IR) in forecasting metabolic syndrome (MetS) risk, especially within the Iranian population afflicted with type 2 diabetes mellitus (T2DM). The present investigation aimed to assess the efficacy of IR indices in predicting the risk of MetS among T2DM patients. Convenient sampling was utilized to select four hundred subjects with T2DM. Metabolic factors and IR indices, including the Waist Circumference-Triglyceride Index (WTI), Triglyceride and Glucose Index (TyG index), the product of TyG index and abdominal obesity indices, and the Metabolic Score for Insulin Resistance (METS-IR), were evaluated. Logistic regression, coupled with modeling, was employed to explore the risk of MetS. The predictive performance of the indices for MetS stratified by sex was evaluated via receiver operating characteristic (ROC) curve analysis and estimation of the area under the curve (AUC) values. The TyG-Waist Circumference (TyG-WC) index exhibited the largest AUCs in both males (0.91) and females (0.93), while the TyG-Body Mass Index (TyG-BMI) demonstrated the smallest AUCs (0.77 in males and 0.74 in females). All indices significantly predicted the risk of MetS in all subjects before and after adjustment (p < 0.001 for all). The TyG-WC index demonstrated the highest odds ratios for MetS (8.06, 95% CI 5.41-12.00). In conclusion, all IR indices assessed in this study effectively predicted the risk of MetS among Iranian patients with T2DM, with the TyG-WC index emerging as the most robust predictor across both genders.

Evidence related to a vegetarian diet and metabolic dysfunction-associated steatotic liver disease: protocol for a scoping review

INTRODUCTION

Metabolic dysfunction-associated fatty liver disease (MASLD) is the hepatic manifestation of metabolic syndrome and the leading cause of chronic liver disease worldwide. Given that there is no pharmacological treatment for MASLD, it is imperative to understand whether lifestyle modifications may improve biochemical and pathological outcomes. One commonly proposed dietary modification is the Mediterranean diet; however, vegetarianism may also be a promising intervention. Vegetarianism has been shown to be associated with reduced morbidity and mortality in metabolic syndrome outcomes in coronary artery disease and diabetes; however, the relationship between vegetarian diet and MASLD is less clear. In this scoping review, we will provide a comprehensive overview of the current body of evidence related to a vegetarian diet and MASLD.

METHODS AND ANALYSIS

The aim of this scoping review is to describe and summarise the current body of evidence related to MASLD and a vegetarian diet. This review will be conducted using Arksey and O'Malley's framework. The literature review will be conducted using the following databases: SCOPUS, Web of Science, CINAHL-Plus, Cochrane Library and Medline. No restriction will be made on publication date. Included studies will encompass clinical trials and observational designs that examine effects or association of vegetarian diet in adults (≥16 years) and report on the incidence, prevalence or progression of MASLD. Grey literature, non-human studies and articles focusing on changes in a specific food or nutraceutical will be excluded. Articles must have an English-language abstract available to be considered for inclusion. Screening and data extraction will be conducted by two independent reviewers. The findings will be summarised with descriptive statistics.

ETHICS AND DISSEMINATION

Approval from a medical ethics committee is not required for this review. Once the review is complete, the findings will be submitted to a peer-reviewed journal.

Associations of ALT/AST, a marker of hepatosteatosis, with pulse rate in young women and with blood pressure in middle-aged women independently of abdominal fat accumulation and insulin resistance

We examined whether alanine aminotransferase/aspartate aminotransferase (ALT/AST), a marker of hepatosteatosis, may be associated with a wider constellation of variables related to metabolic syndrome in Japanese women. Body fat and distribution, and metabolic syndrome-related variables were measured in 311 young and 148 middle-aged women. We had Pearson's correlation analysis and then stepwise multivariate linear regression analyses. In both middle-aged and young women, ALT/AST was associated with homeostasis model assessment insulin resistance (HOMA-IR), trunk/leg fat ratio and pulse rate. In middle-aged women but not in young women, ALT/AST was associated with waist circumference, fasting glucose, triglyceride, HDL cholesterol (inversely), systolic, diastolic and mean blood pressure (BP). Further, in middle-aged women only, the ratio was associated with BMI, percentage body fat, apolipoprotein B and plasminogen activator inhibitor-1. Among these variables, pulse rate in young women and systolic BP in middle-aged women were associated with ALT/AST independently of trunk/leg fat ratio, a sophisticated measures of abdominal fat accumulation,　HOMA-IR, fasting glucose, triglyceride and HDL cholesterol. In conclusion, ALT/AST was associated with pulse rate in young women and with systolic BP in middle-aged women independently of abdominal fat accumulation and insulin resistance. It is noted that their waist circumference averaged < 80 cm and ALT < 30 U/L, suggesting minimum accumulation of abdominal and hepatic fat, respectively, key drivers of insulin resistance and metabolic syndrome.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-023-00689-z.

A revisit of drugs and potential therapeutic targets against non-alcoholic fatty liver disease: learning from clinical trials

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease, with a worldwide prevalence of 25%. Although numerous clinical trials have been conducted over the last few decades, an effective treatment has not been approved yet. Extensive research has accumulated a large amount of data and experience; however, the vast number of clinical trials and new therapeutic targets for NAFLD make it impossible to keep abreast of the relevant information. Therefore, a systematic analysis of the existing trials is necessary.

METHODS

Here, we reviewed clinical trials on NAFLD registered in the mandated federal database, ClinicalTrials.gov, to generate a detailed overview of the trials related to drugs and therapeutic targets for NAFLD treatment. Following screening for pertinence to therapy, a total of 440 entries were identified that included active trials as well as those that have already been completed, suspended, terminated, or withdrawn.

RESULTS

We summarize and systematically analyze the state, drug development pipeline, and discovery of treatment targets for NAFLD. We consider possible factors that may affect clinical outcomes. Furthermore, we discussed these results to explore the mechanisms responsible for clinical outcomes.

CONCLUSION

We summarised the landscape of current clinical trials and suggested the directions for future NAFLD therapy to assist internal medicine specialists in treating the whole clinical spectrum of this highly prevalent liver disease.

Non-alcoholic fatty liver disease and gestational diabetes mellitus: a bidirectional two-sample mendelian randomization study

PURPOSE

Previous observational studies have revealed a potential link between non-alcoholic fatty liver disease (NAFLD) and gestational diabetes mellitus (GDM), but their causal relationship remains unclear. Thus, this study aimed to examine whether a causal link exists between genetically determined NAFLD and GDM.

METHODS

Utilizing publicly accessible genome-wide association studies (GWAS), a two-sample bidirectional Mendelian randomization (MR) analysis was conducted. The GWASs data pertaining to NAFLD and GDM were obtained from the UK Biobank Consortium and FinnGen database in primary analysis, respectively. The random-effects inverse variance weighted (IVW) method was utilized as primary analysis method. Several sensitivity analyses were utilized to verify the robustness of the results. Additionally, we also analyzed the causal effect of potential shared influencing factors on these two conditions.

RESULTS

The result of the IVW method showed that there was no significant causal relationship between genetically determined NAFLD and GDM (OR = 0.98, 95% CI: 0.90-1.07, P = 0.691). Similarly, our reverse MR analysis failed to detect a significant causal effect of GDM on NAFLD (OR = 1.14, 95% CI: 0.97-1.36, P = 0.118). Sensitivity analyses further confirmed the robustness of the results. Moreover, we found that genetically determined body mass index, waist-to-hip ratio, triglycerides, and television viewing time may be positively correlated with NAFLD and GDM, while high-density lipoprotein cholesterol and apolipoprotein A-I may both be negatively correlated with NAFLD and GDM.

CONCLUSIONS

The current bidirectional MR study failed to provide sufficient genetic evidence for the causal relationship between NAFLD and GDM.

Prevalence of Steatotic Liver Disease Among US Adults with Rheumatoid Arthritis

BACKGROUND

The prevalence of steatotic liver disease (SLD) among patients with rheumatoid arthritis (RA) remains largely unknown.

AIMS

To investigate the prevalence of SLD and liver fibrosis among patients with RA.

METHODS

We utilized data from the United States (US)-based National Health and Nutrition Examination Survey (NHANES) 2017-2020 cycle. After applying established sample weights, we estimated the age-adjusted prevalence of SLD and its subclassifications (CAP ≥ 285 dB/m), high-risk NASH (FAST score) and liver fibrosis (LSM) among participants with self-reported RA. Multivariable logistic regression was performed to identify independent risk factors for metabolic dysfunction associated SLD (MASLD), high-risk NASH and fibrosis, respectively, among participants with RA. We present adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

RESULTS

Age-adjusted prevalence of MASLD among US adults with RA was 34.91% (95% CI: 24.02-47.65%). We also found that the age-adjusted prevalence of high-risk NASH (FAST score > 0.35) and significant fibrosis (LSM > 8.6 kPa) was 12.97% (95% CI: 6.89-23.07%) and 10.35% (95% CI: 5.55-18.48%), respectively. BMI ≥ 30 kg/m2, (aOR 6.23; 95% CI: 1.95-19.88), diabetes (aOR 5.90; 95% CI: 1.94-17.94), and dyslipidemia (aOR 2.83; 95% CI: 1.12-7.11) were independently associated with higher odds of MASLD among participants with RA. Diabetes (aOR 19.34; 95% CI: 4.69-79.70) was also independently associated with high-risk NASH.

CONCLUSIONS

The prevalence of MASLD, high-risk NASH, and liver fibrosis among patients with RA is equal or higher than the general population. Future studies of large cohorts are needed to substantiate the role of systemic inflammation in the pathophysiology of MASLD.

Serum Tsukushi Level Is Associated With the Severity of Liver Fibrosis Independent of Type 2 Diabetes

BACKGROUND AND AIMS

Tsukushi (TSK) is a recently identified hepatokine, and we aimed to investigate the association between systemic TSK and the severity of nonalcoholic fatty liver disease (NAFLD) in subjects with and without type 2 diabetes mellitus (DM).

METHODS

Three hundred ninety-three DM and 289 without DM individuals were recruited for transient elastography assessment to determine liver steatosis and fibrosis. Serum TSK was measured by ELISA. The presence of NAFLD was defined as controlled attenuation parameter ≥ 248 dB/m.

RESULTS

NAFLD was present in 276 (70.2%) and 129 (44.6%) subjects with and without DM respectively, and they had higher serum TSK levels than those without NAFLD [DM group: 91.0 ng/mL (61.7-133.8) vs 82.5 (60.9-118.5), P < .01 respectively; without DM group: 97.1 ng/mL (69.3-148.6) vs 80.8 (53.4-111.6) respectively, P < .01]. Univariate analysis showed that serum TSK significantly correlated with the degree of steatosis and fibrosis both in subjects with and without DM. On multivariable regression analysis, only liver stiffness and estimated glomerular filtration rate were significant determinants of TSK level, and the relationship was independent of diabetes and serum adiponectin. Out of 405 subjects with NAFLD, 49 had either advanced fibrosis or cirrhosis. The area under receiver operating characteristic curve of serum TSK to indicate advanced fibrosis or cirrhosis was 0.70 (95% CI .62-.77), which was significantly better than that of fibrosis-4 index, 0.64 (95% CI .55-.72), P < .05.

CONCLUSION

Serum TSK levels were increased in subjects with NAFLD and reflected the severity of liver fibrosis.

Hepatoprotection of capsaicin in alcoholic and non-alcoholic fatty liver diseases

Alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD) are common causes of chronic liver disease that share the range of steatosis, steatohepatitis, fibrosis, cirrhosis, and finally, hepatocellular carcinoma. They are identified by the dysregulation of disease-specific signalling pathways and unique microRNAs. Capsaicin is an active ingredient of chilli pepper that acts as an agonist of transient receptor potential vanilloid subfamily 1. It seems that the protective role of capsaicin against NAFLD and ALD is linked to its anti-steatotic, antioxidant, anti-inflammatory, and anti-fibrotic effects. Capsaicin-induced inhibiting metabolic syndrome and gut dysbiosis and increasing bile acids production are also involved in its anti-NAFLD role. This review summarises the different molecular mechanisms underlying the protective role of capsaicin against NAFLD and ALD. More experimental studies are needed to clarify the effects of capsaicin on the expression of genes involved in hepatic lipid metabolism and hepatocytes apoptosis in NAFLD and ALD.

Myocardial tissue remodeling in early adult obesity and its association with regional adipose tissue distribution and ectopic fat deposits: a prospective study

OBJECTIVES

To evaluate the left ventricular (LV) myocardial tissue characteristics in early adult obesity and its association with regional adipose tissue and ectopic fat deposition.

METHODS

Forty-nine obese adults (mean body mass index: 29.9 ± 2.0 kg/m2) and 44 healthy controls were prospectively studied. LV native and post-contrast T1 values, extracellular volume fraction (ECV), regional adipose tissue (epicardial, visceral, and subcutaneous adipose tissue (EAT, VAT, and SAT)), and ectopic fat deposition (hepatic and pancreatic proton density fat fractions (H-PDFF and P-PDFF)) based on magnetic resonance imaging were compared. The association was assessed by multivariable linear regression.

RESULTS

The obese participants showed reduced global ECV compared to the healthy controls (p < 0.05), but there was no significant difference in global native or post-contrast T1 values between the two groups. Additionally, the obese individuals exhibited higher EAT, VAT, SAT, H-PDFF, and P-PDFF than the controls (p < 0.05). ECV was associated with insulin resistance, dyslipidemia, and systolic blood pressure (SBP) (p < 0.05). Multiple linear regression demonstrated that H-PDFF and SAT were independently associated with ECV in entire population (β =  - 0.123 and - 0.012; p < 0.05).

CONCLUSIONS

Reduced myocardial ECV in patients with mild-to-moderate obesity and its relationship to SBP may indicate that cardiomyocyte hypertrophy, rather than extracellular matrix expansion, is primarily responsible for myocardial tissue remodeling in early adult obesity. Our findings further imply that H-PDFF and SAT are linked with LV myocardial tissue remodeling in this cohort beyond the growth difference and cardiovascular risk factors.

CLINICAL TRIALS REGISTRATION

Effect of lifestyle intervention on metabolism of obese patients based on smart phone software (ChiCTR1900026476).

CLINICAL RELEVANCE STATEMENT

Myocardial fibrosis in severe obesity predicts poor prognosis. We showed that cardiomyocyte hypertrophy, not myocardial fibrosis, is the main myocardial tissue characteristic of early obesity. This finding raises the possibility that medical interventions, like weight loss, may prevent cardiac fibrosis.

KEY POINTS

• Myocardial tissue characteristics in early adult obesity are unclear. • Myocardial extracellular volume fraction (ECV) can be quantitatively evaluated using T1 mapping based on cardiac magnetic resonance imaging (MRI). • Cardiac MRI-derived ECV may noninvasively evaluate myocardial tissue remodeling in early adult obesity.

Alzheimer's disease-related brain insulin resistance and the prospective therapeutic impact of metformin

Besides COVID-19, two of the most critical outbreaks of our day are insulin resistance, type 2 diabetes mellitus (T2DM), and Alzheimer's disease (AD). Each disease's pathophysiology is well established. Furthermore, a substantial overlap between them has coexisted. Uncertainty remains on whether T2DM and AD are parallel illnesses with the same origin or separate illnesses linked through violent pathways. The current study was aimed at testing whether the insulin resistance in the brain results in AD symptoms or not. Insulin resistance was induced in the brains of rats using a single intracerebroventricular streptozotocin (STZ) dose. We then measured glucose, insulin receptor substrate 2 (IRS-2), amyloid β (Aβ) deposition, and tau phosphorylation in the brain to look for signs of insulin resistance and AD. The results of this study indicated that a single dose of STZ was able to induce insulin resistance in the brain and significantly decline IRS-2. This resistance was accompanied by obvious memory loss, Aβ deposition, and tau phosphorylation, further visible diminishing in neurotransmitters such as dopamine and acetylcholine. Furthermore, oxidative stress was increased due to the antioxidant system being compromised. Interestingly, the pancreas injury and peripheral insulin resistance coexisted with brain insulin resistance. Indeed, the antidiabetic metformin was able to enhance all these drastic effects. In conclusion, brain insulin resistance could lead to AD and vice versa. These are highly linked syndromes that could influence peripheral organs. Further studies are required to stabilize this putative pathobiology relationship between them.

Receptor-interacting protein 1 and 3 kinase activity are required for high-fat diet induced liver injury in mice

Background

The RIP1-RIP3-MLKL-mediated cell death pathway is associated with progression of non-alcohol-associated fatty liver/steatohepatitis (NAFL/NASH). Previous work identified a critical role for MLKL, the key effector regulating necroptosis, but not RIP3, in mediating high fat diet-induced liver injury in mice. RIP1 and RIP3 have active N-terminus kinase domains essential for activation of MLKL and subsequent necroptosis. However, little is known regarding domain-specific roles of RIP1/RIP3 kinase in liver diseases. Here, we hypothesized that RIP1/RIP3 kinase activity are required for the development of high fat diet-induced liver injury.

Methods

Rip1K45A/K45A and Rip3K51A/K51A kinase-dead mice on a C57BL/6J background and their littermate controls (WT) were allowed free access to a diet high in fat, fructose and cholesterol (FFC diet) or chow diet.

Results

Both Rip1K45A/K45A and Rip3K51A/K51A mice were protected against FFC diet-induced steatosis, hepatocyte injury and expression of hepatic inflammatory cytokines and chemokines. FFC diet increased phosphorylation and oligomerization of MLKL and hepatocyte death in livers of WT, but not in Rip3K51A/K51A, mice. Consistent with in vivo data, RIP3 kinase deficiency in primary hepatocytes prevented palmitic acid-induced translocation of MLKL to the cell surface and cytotoxicity. Additionally, loss of Rip1 or Rip3 kinase suppressed FFC diet-mediated formation of crown-like structures (indicators of dead adipocytes) and expression of mRNA for inflammatory response genes in epididymal adipose tissue. Moreover, FFC diet increased expression of multiple adipokines, including leptin and plasminogen activator inhibitor 1, in WT mice, which was abrogated by Rip3 kinase deficiency.

Discussion

The current data indicate that both RIP1 and RIP3 kinase activity contribute to FFC diet-induced liver injury. This effect of RIP1 and RIP3 kinase deficiency on injury is consistent with the protection of Mlkl-/- mice from high fat diet-induced liver injury, but not the reported lack of protection in Rip3-/- mice. Taken together with previous reports, our data suggest that other domains of RIP3 likely counteract the effect of RIP3 kinase in response to high fat diets.

Associations of Alanine Aminotransferase/Aspartate Aminotransferase, a Marker of Hepatosteatosis, with Adipose Tissue Insulin Resistance Index and Leptin/Adiponectin Ratio in Japanese Women

Objective: We assessed whether alanine aminotransferase/aspartate aminotransferase (ALT/AST), a marker of hepatic steatosis, may be associated with adipose tissue dysfunction more closely than hepatic and muscle insulin resistance (IR). Methods: Associations with adipose tissue IR index (AT-IR) calculated as a product of fasting insulin and free fatty acids, leptin/adiponectin ratio, a proxy of adipocyte dysfunction, homeostasis model assessment IR (HOMA-IR), hepatic and muscle IR inferred from plasma insulin kinetics during a 75 grams oral glucose tolerance test (OGTT) were studied in nondiabetic 307 young and 148 middle-aged Japanese women, whose body mass index averaged 20 and 22 kilograms/m2, respectively. Results: On multivariate linear regression analysis in young women, ALT/AST was associated with trunk/leg fat ratio (standardized β = 0.202, P = 0.007), a marker of abdominal fat accumulation, and AT-IR (standardized β = 0.185, P = 0.003) independently of HOMA-IR and Matsuda index (R2 = 0.07). In middle-aged women, leptin/adiponectin ratio (standardized β = 0.446, P < 0.001) and AT-IR (standardized β = 0.292, P = 0.009) emerged as determinants of ALT/AST independently of trunk/leg fat ratio, OGTT-derived hepatic IR, leptin, and adiponectin (R2 = 0.34). Conclusions: ALT/AST was associated with AT-IR and adipocyte dysfunction more closely than hepatic and muscle IR even in nondiabetic lean Japanese women.

HCC is associated with diabetes and longitudinal blood glucose control in a national cohort with cirrhosis

BACKGROUND

Diabetes is associated with HCC; however, the impact of longitudinal blood glucose (BG) control on HCC risk in cirrhosis is not well known. We investigated this knowledge gap in a cohort of United States Veterans with cirrhosis from 2015 to 2021.

METHODS

We used repeated hemoglobin A1c measurements to categorize follow-up time according to BG control (defined as hemoglobin A1c < 7%) state over time: uncontrolled, nonsustained control (≤2 y), or sustained control (>2 y). We performed a sensitivity analysis using hemoglobin A1c < 8% to define BG control. We used Fine and Gray Cox proportional hazards regression with death and transplant as competing events to compare rates of incident HCC.

RESULTS

Our study included 81,907 individuals, 56.2% of whom had diabetes at baseline. There were 8,002 incident HCCs. The rate of HCC was 18% higher in diabetes (95% CI: 13% - 24%), and the relative increase in the rate of HCC varied by etiology of cirrhosis from nonsignificant (HCV) to an increase of 120% (HBV). Uncontrolled and nonsustained BG control was associated with 1.80 (95% CI: 1.70-1.91) and 2.34 (95% CI: 2.21-2.48) times the rate of HCC compared to sustained BG control, respectively. Using Hgb A1c < 8% to define BG control, HCC rates in uncontrolled and nonsustained BG control were 2.43 (2.28-2.58) and 2.23 (2.11-2.36) times that observed in sustained BG control.

CONCLUSIONS

Associations between diabetes and HCC in cirrhosis vary according to the longitudinal BG control state. Inadequate BG control is consistently associated with a higher risk of HCC, and long-term BG control should be considered in comprehensive cirrhosis care.

History of Gestational Diabetes and Incident Nonalcoholic Fatty Liver Disease: The Kangbuk Samsung Health Study

INTRODUCTION

We examined the relationship between a previous history of gestational diabetes mellitus (pGDM) and risk of incident nonalcoholic fatty liver disease (NAFLD) and investigated the effect of insulin resistance or development of diabetes as mediators of any association.

METHODS

We performed a retrospective cohort study of 64,397 Korean parous women without NAFLD. The presence of and the severity of NAFLD at baseline and follow-up were assessed using liver ultrasonography. Cox proportional hazards models were used to determine adjusted hazard ratios for incident NAFLD according to a self-reported GDM history, adjusting for confounders as time-dependent variables. Mediation analyses were performed to examine whether diabetes or insulin resistance may mediate the association between pGDM and incident NAFLD.

RESULTS

During a median follow-up of 3.7 years, 6,032 women developed incident NAFLD (of whom 343 had moderate-to-severe NAFLD). Multivariable adjusted hazard ratios (95% confidence intervals) comparing women with time-dependent pGDM with the reference group (no pGDM) were 1.46 (1.33-1.59) and 1.75 (1.25-2.44) for incident overall NAFLD and moderate-to-severe NAFLD, respectively. These associations remained significant in analyses restricted to women with normal fasting glucose <100 mg/dL or that excluded women with prevalent diabetes at baseline or incident diabetes during follow-up. Diabetes and insulin resistance (Homeostatic Model Assessment for Insulin Resistance) each mediated <10% of the association between pGDM and overall NAFLD development.

DISCUSSION

A previous history of GDM is an independent risk factor for NAFLD development. Insulin resistance, measured by the Homeostatic Model Assessment for Insulin Resistance, and development of diabetes each explained only <10% of the association between GDM and incident NAFLD.

Aerobic Exercise Ameliorates Liver Injury in Db/Db Mice by Attenuating Oxidative Stress, Apoptosis and Inflammation Through the Nrf2 and JAK2/STAT3 Signalling Pathways

Objective

Diabetes mellitus (DM) implicates oxidative stress, apoptosis, and inflammation, all of which may contribute liver injury. Aerobic exercise is assured to positively regulate metabolism in the liver. This project was designed to investigate whether and how aerobic exercise improves DM-induced liver injury.

Methods

Seven-week-old male db/db mice and age-matched m/m mice were randomly divided into a rest control group or a group that received 12 weeks of aerobic exercise by treadmill training (10 m/min). Haematoxylin and eosin (HE) staining, electron microscopy, Oil Red O staining and TUNEL assays were used to evaluate the histopathological changes in mouse liver. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TRIG), cholesterol (CHOL) were analyzed by serum biochemical analysis. Interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), and tissue levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were analyzed via ELISA. Nuclear factor E2-associated factor-2 (Nrf2), nuclear factor κB (NF-κB) and JAK2/STAT3 pathway-related proteins were measured by immunofluorescence, Western blotting and q-PCR. F4/80 expression in liver tissues was assessed by immunohistochemistry.

Results

In diabetic mice, exercise training significantly decreased the levels of serum TRIG, CHOL, IL-6, TNF-α, ALT and AST; prevented weight gain, hyperglycaemia, and impaired glucose and insulin tolerance. Morphologically, exercise mitigated the diabetes-induced increase in liver tissue microvesicles, inflammatory cells, F4/80 (macrophage marker) levels, and TUNEL-positive cells. In addition, exercise reduced the apoptosis index, which is consistent with the results for caspase-3 and Bax. Additionally, exercise significantly increased SOD activity, decreased MDA levels, activated Nrf2 and decreased the expression of NF-kB, phosphorylated JAK2 and STAT3 proteins in the livers of diabetic mice.

Conclusion

This study demonstrated that aerobic exercise reversed liver dysfunction in db/db mice with T2DM by reducing oxidative stress, apoptosis and inflammation, possibly by enhancing Nrf2 expression and inhibiting the JAK2/STAT3 cascade response.

Clinical Profile of Nonalcoholic Fatty Liver Disease and its Correlation with Metabolic Syndrome and Cardiovascular Risk

Background

Nonalcoholic fatty liver disease (NAFLD) has been projected, within the next 20 years, to become the major cause of liver-related morbidity and mortality as well as a leading indication for liver transplantation. Affected South Asian Indians are at higher risk for the development of metabolic syndrome (MS), type 2 diabetes, and cardiovascular disease. There is a dearth of data related to NAFLD and its various sequelae and correlation with cardiovascular disease in South Asia.

Materials and Methods

It was an observational, prospective study conducted over 2 years on 80 patients in a tertiary care hospital in Mumbai. All patients diagnosed with NAFLD were investigated for MS according to the National Cholesterol Education Program Adult Treatment Panel III criteria, and a relationship between NAFLD and MS was correlated.

Results

MS was found to be present in 72.5% of the patients. Significant results were obtained while correlating MS parameters and fatty liver grading, implying that patients with a higher fatty liver grading were more likely to have derangements in metabolic markers.

Conclusion

NAFLD was found to be associated with an increased incidence of MS and thereby a higher risk of cardiovascular disease, warranting a high index of suspicion for both. A higher ultrasound grading of fatty liver was found to be associated with an increased incidence of MS.

Relationship between nonalcoholic fatty liver disease and hyperandrogenemia in adolescents with polycystic ovary syndrome

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is common in adults with polycystic ovary syndrome (PCOS), and several studies on adults have investigated its influencing factors. However, factors associated with NAFLD in adolescents with PCOS remain unknown.

PURPOSE

This study aimed to investigate the presence of NAFLD in adolescents with PCOS using the noninvasive methods of vibration-controlled transient elastography (VCTE) and ultrasonography (USG), along with assessing NAFLD-related metabolic and hormonal risk factors.

METHODS

This study included patients aged 12-18 years who were diagnosed with PCOS according to the Rotterdam criteria. The control group included young women with similar age and body mass index (BMI) z scores, who had menstruated regularly for more than 2 years. Patients with PCOS were divided into hyperandrogenemia and nonhyperandrogenemia groups based on serum androgen level. USG was performed on all patients to evaluate the presence of hepatic steatosis. Liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) were assessed using VCTE (Fibroscan). Clinical, laboratory, and radiological data were compared between groups.

RESULTS

This study included 124 adolescent girls aged 12-18 years (61 with PCOS, 63 controls). BMI z scores were similar between groups. Waist circumference and total cholesterol, triglyceride, and alanine aminotransferase levels were higher in the PCOS versus the control group. The presence of hepatic steatosis on USG was similar between groups. However, the rate of hepatic steatosis on USG was higher in patients with hyperandrogenic PCOS (P=0.01). LSM and CAP measurements were similar between groups.

CONCLUSION

No increase in prevalence of NAFLD was observed among adolescents with PCOS. However, hyperandrogenemia is a risk factor for NAFLD. Therefore, adolescents with PCOS and elevated androgen level should be screened for NAFLD.

CRISPR/Cas9-Based Screening of FDA-Approved Drugs for NRF2 Activation: A Novel Approach to Discover Therapeutics for Non-Alcoholic Fatty Liver Disease

With the rising prevalence of obesity, non-alcoholic fatty liver disease (NAFLD) now affects 20-25% of the global population. NAFLD, a progressive condition associated with oxidative stress, can result in cirrhosis and liver cancer in 10% and 3% of patients suffering NAFLD, respectively. Therapeutic options are currently limited, emphasizing the need for novel treatments. In this study, we examined the potential of activating the transcription factor NRF2, a crucial player in combating oxidative stress, as an innovative approach to treating NAFLD. Utilizing a CRISPR/Cas9-engineered human HEK293T cell line, we were able to monitor the expression of heme oxygenase-1 (HMOX1), an NRF2 target, using a Nanoluc luciferase tag. Our model was validated using a known NRF2 activator, after which we screened 1200 FDA-approved drugs, unearthing six compounds (Disulfiram, Thiostrepton, Auranofin, Thimerosal, Halofantrine, and Vorinostat) that enhanced NRF2 activity and antioxidant response. These compounds demonstrated protective effects against oxidative stress induced by hydrogen peroxide and lipid droplets accumulation in vitro with hepatoma HUH-7 cells. Our study underscores the utility of CRISPR/Cas9 tagging with Nanoluc luciferase in identifying potential NRF2 activators, paving the way for potential NAFLD therapeutics.

Experimental Data on the Role of Melatonin in the Pathogenesis of Nonalcoholic Fatty Liver Disease

Despite the increasing prevalence of nonalcoholic fatty liver disease (NAFLD) worldwide, its complex pathogenesis remains incompletely understood. The currently stated hypotheses cannot fully clarify the interrelationships between individual pathogenetic mechanisms of the disease. No appropriate health strategies have been developed for treating NAFLD. NAFLD is characterized by an accumulation of triglycerides in hepatic cells (steatosis), with the advanced form known as nonalcoholic steatohepatitis. In the latter, superimposed inflammation can lead to fibrosis. There are scientific data on NAFLD's association with components of metabolic syndrome. Hormonal factors are thought to play a role in the development of metabolic syndrome. Endogenous melatonin, an indoleamine hormone synthesized by the pineal gland mainly at night, is a powerful chronobiotic that probably regulates metabolic processes and has antioxidant, anti-inflammatory, and genomic effects. Extrapineal melatonin has been found in various tissues and organs, including the liver, pancreas, and gastrointestinal tract, where it likely maintains cellular homeostasis. Melatonin exerts its effects on NAFLD at the cellular, subcellular, and molecular levels, affecting numerous signaling pathways. In this review article, we discuss the experimental scientific data accumulated on the involvement of melatonin in the intimate processes of the pathogenesis of NAFLD.

Food Polyphenols and Type II Diabetes Mellitus: Pharmacology and Mechanisms

Type II diabetes mellitus and its related complications are growing public health problems. Many natural products present in our diet, including polyphenols, can be used in treating and managing type II diabetes mellitus and different diseases, owing to their numerous biological properties. Anthocyanins, flavonols, stilbenes, curcuminoids, hesperidin, hesperetin, naringenin, and phenolic acids are common polyphenols found in blueberries, chokeberries, sea-buckthorn, mulberries, turmeric, citrus fruits, and cereals. These compounds exhibit antidiabetic effects through different pathways. Accordingly, this review presents an overview of the most recent developments in using food polyphenols for managing and treating type II diabetes mellitus, along with various mechanisms. In addition, the present work summarizes the literature about the anti-diabetic effect of food polyphenols and evaluates their potential as complementary or alternative medicines to treat type II diabetes mellitus. Results obtained from this survey show that anthocyanins, flavonols, stilbenes, curcuminoids, and phenolic acids can manage diabetes mellitus by protecting pancreatic β-cells against glucose toxicity, promoting β-cell proliferation, reducing β-cell apoptosis, and inhibiting α-glucosidases or α-amylase. In addition, these phenolic compounds exhibit antioxidant anti-inflammatory activities, modulate carbohydrate and lipid metabolism, optimize oxidative stress, reduce insulin resistance, and stimulate the pancreas to secrete insulin. They also activate insulin signaling and inhibit digestive enzymes, regulate intestinal microbiota, improve adipose tissue metabolism, inhibit glucose absorption, and inhibit the formation of advanced glycation end products. However, insufficient data are available on the effective mechanisms necessary to manage diabetes.

Gene Polymorphisms and Biological Effects of Vitamin D Receptor on Nonalcoholic Fatty Liver Disease Development and Progression

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, with increasing prevalence worldwide. The genetic and molecular background of NAFLD pathogenesis is not yet clear. The vitamin D/vitamin D receptor (VDR) axis is significantly associated with the development and progression of NAFLD. Gene polymorphisms may influence the regulation of the VDR gene, although their biological significance remains to be elucidated. VDR gene polymorphisms are associated with the presence and severity of NAFLD, as they may influence the regulation of adipose tissue activity, fibrosis, and hepatocellular carcinoma (HCC) development. Vitamin D binds to the hepatic VDR to exert its biological functions, either by activating VDR transcriptional activity to regulate gene expression associated with inflammation and fibrosis or by inducing intracellular signal transduction through VDR-mediated activation of Ca²⁺ channels. VDR activity has protective and detrimental effects on hepatic steatosis, a characteristic feature of NAFLD. Vitamin D-VDR signaling may control the progression of NAFLD by regulating immune responses, lipotoxicity, and fibrogenesis. Elucidation of the genetic and molecular background of VDR in the pathophysiology of NAFLD will provide new therapeutic targets for this disease through the development of VDR agonists, which already showed promising results in vivo.

Roles of the peroxisome proliferator-activated receptors (PPARs) in the pathogenesis of nonalcoholic fatty liver disease (NAFLD)

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of disease phenotypes which start with simple steatosis and lipid accumulation in the hepatocytes - a typical histological lesions characteristic. It may progress to non-alcoholic steatohepatitis (NASH) that is characterized by hepatic inflammation and/or fibrosis and subsequent onset of NAFLD-related cirrhosis and hepatocellular carcinoma (HCC). Due to the central role of the liver in metabolism, NAFLD is regarded as a result of and contribution to the metabolic abnormalities seen in the metabolic syndrome. Peroxisome proliferator-activated receptors (PPARs) has three subtypes, which govern the expression of genes responsible for energy metabolism, cellular development, inflammation, and differentiation. The agonists of PPARα, such as fenofibrate and clofibrate, have been used as lipid-lowering drugs in clinical practice. Thiazolidinediones (TZDs) - ligands of PPARγ, such as rosiglitazone and pioglitazone, are also used in the treatment of type 2 diabetes (T2D) with insulin resistance (IR). Increasing evidence suggests that PPARβ/δ agonists have potential therapeutic effects in improving insulin sensitivity and lipid metabolism disorders. In addition, PPARs ligands have been considered as potential therapeutic drugs for hypertension, atherosclerosis (AS) or diabetic nephropathy. Their crucial biological roles dictate the significance of PPARs-targeting in medical research and drug discovery. Here, it reviews the biological activities, ligand selectivity and biological functions of the PPARs family, and discusses the relationship between PPARs and the pathogenesis of NAFLD and metabolic syndrome. This will open new possibilities for PPARs application in medicine, and provide a new idea for the treatment of fatty liver and related diseases.

Combinational administration of mesenchymal stem cell-derived exosomes and metformin reduces inflammatory responses in an in vitro model of insulin resistance in HepG2 cells

Diabetes is a highly common metabolic disorder in advanced societies. One of the causes of diabetes is insulin resistance, which is associated with a loss of sensitivity to insulin-sensitive cells. Insulin resistance develops in the body of a person prone to diabetes many years before diabetes development. Insulin resistance is associated with complications such as hyperglycemia, hyperlipidemia, and compensatory hyperinsulinemia and causes liver inflammation, which, if left untreated, can lead to cirrhosis, fibrosis, and even liver cancer. Metformin is the first line of treatment for patients with diabetes, which lowers blood sugar and increases insulin sensitivity by inhibiting gluconeogenesis in liver cells. The use of metformin has side effects, including a metallic taste in the mouth, vomiting, nausea, diarrhea, and upset stomach. For this reason, other treatments, along with metformin, are being developed. Considering the anti-inflammatory role of mesenchymal stem cells (MSCs) derived exosomes, their use seems to help improve liver tissue function and prevent damage caused by inflammation. This study investigated the anti-inflammatory effect of Wharton's jelly MSCs derived exosomes in combination with metformin in the HepG2 cells insulin resistance model induced by high glucose. This study showed that MSCs derived exosomes as an anti-inflammatory agent in combination with metformin could increase the therapeutic efficacy of metformin without needing to change metformin doses by decreasing inflammatory cytokines production, including IL-1, IL-6, and TNF-α and apoptosis in HepG2 cells.

Enriched functional milk fat ameliorates glucose intolerance and triacylglycerol accumulation in skeletal muscle of rats fed high-fat diets

PURPOSE

We examined the effect of a functional milk fat (FMF) on the glucose metabolism and its association with the intramuscular triacylglycerol (TAG) content in rats fed high-fat diets.

METHODS

Male Wistar rats were fed for 60 days with S7 (soybean oil 7%), S30 (soybean oil 30%), MF30 (soybean oil 3% + milk fat 27%), or FMF30 (soybean oil 3% + FMF 27%) diets. An oral glucose tolerance test was performed. The levels of key metabolites in gastrocnemius muscle and mRNA levels of genes involved in glucose and lipid metabolism in muscle, epididymal white adipose tissue (EWAT), and serum were assessed.

RESULTS

The S30 diet induced glucose intolerance and led to TAG, citrate, and glucose accumulation in muscle. Moreover, we observed a downregulation of uncoupling proteins (Ucp2 and Ucp3) and insulin receptor substrate-1 (Irs1) genes, lower carnitine palmitoyl transferase-1b (CPT-1b), and phosphofructokinase-1 (PFK1) activities in muscle and lower expression of adiponectin (Adipoq) in EWAT. The FMF30 diet ameliorated the glucose intolerance and normalized the glucose and TAG levels in muscle, preventing the accumulation of citrate and enhancing glucose utilization by the PFK1. The beneficial effects might also be related to the higher expression of Adipoq in EWAT, its receptor in muscle (Adipor1), and the expression of Ucp2, Ucp3, and Irs1 in muscle, restoring the alterations observed with the S30 diet.

CONCLUSIONS

FMF30 modulated key genes involved in glucose and lipid metabolism in skeletal muscle, improving the glucose utilization and preventing TAG, glucose, and citrate accumulation.

Short-Term Growth Hormone Administration Mediates Hepatic Fatty Acid Uptake and De Novo Lipogenesis Gene Expression in Obese Rats

Obesity has been linked to metabolic syndrome, type 2 diabetes, and non-alcoholic fatty liver disease (NAFLD). Obesity causes a decrease in growth hormone (GH) levels and an increase in insulin levels. Long-term GH treatment increased lipolytic activity as opposed to decreasing insulin sensitivity. Nonetheless, it is possible that short-term GH administration had no impact on insulin sensitivity. In this study, the effect of short-term GH administration on liver lipid metabolism and the effector molecules of GH and insulin receptors were investigated in diet-induced obesity (DIO) rats. Recombinant human GH (1 mg/kg) was then administered for 3 days. Livers were collected to determine the hepatic mRNA expression and protein levels involved in lipid metabolism. The expression of GH and insulin receptor effector proteins was investigated. In DIO rats, short-term GH administration significantly reduced hepatic fatty acid synthase (FASN) and cluster of differentiation 36 (CD36) mRNA expression while increasing carnitine palmitoyltransferase 1A (CPT1A) mRNA expression. Short-term GH administration reduced hepatic FAS protein levels and downregulated gene transcription of hepatic fatty acid uptake and lipogenesis, while increasing fatty acid oxidation in DIO rats. DIO rats had lower hepatic JAK2 protein levels but higher IRS-1 levels than control rats due to hyperinsulinemia. Our findings suggest that short-term GH supplementation improves liver lipid metabolism and may slow the progression of NAFLD, where GH acts as the transcriptional regulator of related genes.

Risk Scores for Prediction of Major Cardiovascular Events in Non-Alcoholic Fatty Liver Disease: A No Man's Land?

Over the past 100 years, cardiovascular disease (CVD) has become a leading cause of mortality and morbidity in developed countries, and similar trends have occurred for chronic liver disease. Subsequent research also indicated that people with non-alcoholic fatty liver disease (NAFLD) had a twofold increased risk of CV events and that this risk was doubled in those with liver fibrosis. However, no validated CVD risk score specific for NAFLD patients has yet been validated, as traditional risk scores tend to underestimate the CV risk in NAFLD patients. From a practical perspective, identifying NAFLD patients and assessing severity of liver fibrosis when concurrent atherosclerotic risk factors are already established may serve as an important criterion in new CV risk scores. The current review aims to assess current risk scores and their utility for the prediction of CV events among patients with NAFLD.

PPAR-γ signaling in nonalcoholic fatty liver disease: Pathogenesis and therapeutic targets

Non-alcoholic fatty liver disease (NAFLD), currently the leading cause of global chronic liver disease, has emerged as a major public health problem, more efficient therapeutics of which are thus urgently needed. Peroxisome proliferator-activated receptor γ (PPAR-γ), ligand-activated transcription factors of the nuclear hormone receptor superfamily, is considered a crucial metabolic regulator of hepatic lipid metabolism and inflammation. The role of PPAR-γ in the pathogenesis of NAFLD is gradually being recognized. Here, we outline the involvement of PPAR-γ in the pathogenesis of NAFLD through adipogenesis, insulin resistance, inflammation, oxidative stress, endoplasmic reticulum stress, and fibrosis. In addition, the evidence for PPAR-γ- targeted therapy for NAFLD are summarized. Altogether, PPAR-γ is a promising therapeutic target for NAFLD, and the development of drugs that can balance the beneficial and undesirable effects of PPAR-γ will bring new light to NAFLD patients.

Risk Factors of Non-alcoholic Fatty Liver Disease in the Iranian Adult Population: A Systematic Review and Meta-analysis

Context: Non-alcoholic fatty liver disease (NAFLD) is progressing considerably worldwide. Identifying the risk factors of NAFLD is a critical step in preventing its progression. Methods: In November 2022, two independent researchers studied seven databases, including PubMed, ISI/WoS, ProQuest, Scopus, SID, Magiran, and Google Scholar, and reference list of relevant articles, searching studies that assessed NAFLD risk factors in the Iranian adult population. Heterogeneity between studies was assessed by Cochran’s test and its composition using I2 statistics. A random-effects model was used when heterogeneity was observed; otherwise, a fixed-effects model was applied. Egger’s regression test and Trim-and-Fill analysis were used to assess publication bias. Comprehensive Meta-analysis software (version 3) was used for the analyses of the present study. Results: The results of this study showed significant associations between NAFLD with age [n = 15, odds ratio (OR) = 2.12, 95% CI: 1.79 - 2.51], body mass index (n = 46, OR = 5.00, 95% CI: 3.34 - 7.49), waist circumference (n = 20, OR = 6.37, 95% CI: 3.25 - 12.48), waist-to-hip ratio (n = 17, OR = 4.72, 95% CI: 3.93 - 5.66), total cholesterol (n = 39, OR = 1.80, 95% CI: 1.52 - 2.13), high-density lipoprotein (n = 37, OR = 0.53, 95% CI: 0.44 - 0.65), low-density lipoprotein (n = 31, OR = 1.68, 95% CI: 1.38 - 2.05), triglyceride (n = 31, OR = 3.21, 95% CI: 2.67 - 3.87), alanine aminotransferase (n = 26, OR = 4.06, 95% CI: 2.94 - 5.62), aspartate aminotransferase (n = 27, OR = 2.16, 95% CI: 1.50 - 3.12), hypertension (n = 13, OR = 2.53, 95% CI: 2.32 - 2.77), systolic blood pressure (n = 13, OR = 1.83, 95% CI: 1.53 - 2.18), diastolic blood pressure (n = 14, OR = 1.80, 95% CI: 1.48 - 2.20), fasting blood sugar (n = 31,OR = 2.91, 95% CI: 2.11- 4.01), homeostatic model assessment for insulin resistance (n = 5, OR = 1.92, 95% CI: 1.48 - 2.59), diabetes mellitus (n = 15, OR = 3.04, 95% CI: 2.46 - 3.75), metabolic syndrome (n = 10, OR = 3.56, 95% CI: 2.79 - 4.55), and physical activity (n = 11, OR = 0.32, 95% CI: 0.24 - 0.43) (P < 0.05). Conclusions: In conclusion, several factors are significantly associated with NAFLD. However, anthropometric indices had the strongest relationship with NAFLD in the Iranian adult population.

Prevalence of Small Intestinal Bacterial Overgrowth Syndrome in Patients with Non-Alcoholic Fatty Liver Disease/Non-Alcoholic Steatohepatitis: A Cross-Sectional Study

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is a multifactorial, wide-spectrum liver disorder. Small intestinal bacterial overgrowth (SIBO) is characterized by an increase in the number and/or type of colonic bacteria in the upper gastrointestinal tract. SIBO, through energy salvage and induction of inflammation, may be a pathophysiological factor for NAFLD development and progression.

AIM/METHODS

Consecutive patients with histological, biochemical, or radiological diagnosis of any stage of NAFLD (non-alcoholic fatty liver [NAFL], non-alcoholic steatohepatitis [NASH], cirrhosis) underwent upper gastrointestinal endoscopy. Duodenal fluid (2cc) was aspirated from the 3rd-4th part of duodenum into sterile containers. SIBO was defined as ≥103 aerobic colony-forming units (CFU)/mL of duodenal aspirate and/or the presence of colonic-type bacteria. Patients without any liver disease undergoing gastroscopy due to gastroesophageal reflux disease (GERD) comprised the healthy control (HC) group. Concentrations (pg/mL) of tumor necrosis factor alpha (TNFα), interleukin (IL)-1β, and IL-6 were also measured in the duodenal fluid. The primary endpoint was to evaluate the prevalence of SIBO in NAFLD patients, while the comparison of SIBO prevalence among NAFLD patients and healthy controls was a secondary endpoint.

RESULTS

We enrolled 125 patients (51 NAFL, 27 NASH, 17 cirrhosis, and 30 HC) aged 54 ± 11.9 years and with a weight of 88.3 ± 19.6 kg (NAFLD vs. HC 90.7 ± 19.1 vs. 80.8 ± 19.6 kg, p = 0.02). Overall, SIBO was diagnosed in 23/125 (18.4%) patients, with Gram-negative bacteria being the predominant species (19/23; 82.6%). SIBO prevalence was higher in the NAFLD cohort compared to HC (22/95; 23.2% vs. 1/30; 3.3%, p = 0.014). Patients with NASH had higher SIBO prevalence (6/27; 22.2%) compared to NAFL individuals (8/51; 15.7%), but this difference did not reach statistical significance (p = 0.11). Patients with NASH-associated cirrhosis had a higher SIBO prevalence compared to patients with NAFL (8/17; 47.1% vs. 8/51; 15.7%, p = 0.02), while SIBO prevalence between patients with NASH-associated cirrhosis and NASH was not statistically different (8/17; 47.1% vs. 6/27; 22.2%, p = 0.11). Mean concentration of TNF-α, IL-1β, and IL-6 did not differ among the different groups.

CONCLUSION

The prevalence of SIBO is significantly higher in a cohort of patients with NAFLD compared to healthy controls. Moreover, SIBO is more prevalent in patients with NASH-associated cirrhosis compared to patients with NAFL.

Associations between Adipokines and Metabolic Dysfunction-Associated Fatty Liver Disease Using Three Different Diagnostic Criteria

Background: A panel of experts proposed a new definition of metabolic dysfunction-associated fatty liver disease (MAFLD) in 2020. To date, the associations between adipokines, such as adiponectin, adipsin, and visfatin and MAFLD remain unclear. Therefore, we aimed to evaluate the associations between each of these three adipokines and MAFLD using different diagnostic criteria. Methods: In total, 221 participants were included in our study based on medical examination. Detailed questionnaire information, physical examination, abdominal ultrasound, and blood-biochemical-test indexes were collected. The levels of adipokines were tested by using an enzyme immunoassay. Logistic regression models were used to assess the associations of the adipokines with MAFLD. Results: In total, 122 of the participants were diagnosed with MAFLD. Higher levels of adipsin and lower levels of adiponectin were found in the MAFLD group than in the non-MAFLD group (all p < 0.05). According to the logistic regression analysis, the ORs were 0.11 (95% CI: 0.05–0.23) for adiponectin, 4.46 (95% CI: 2.19–9.12) for adipsin, and 0.51 (95% CI: 0.27–0.99) for visfatin when comparing the highest tertile with the lowest tertile (all p-trend < 0.05). The inverse association between adiponectin and MAFLD was strongest when T2DM was used as the diagnostic criterion alone, and the positive association between adipsin and MAFLD was strongest when BMI was used as the diagnostic criterion alone. There was no significant association between visfatin and MAFLD, regardless of whether each of BMI, T2DM, or metabolic dysregulation (MD) was used as the diagnostic criterion for MAFLD alone. Conclusion: Adipsin levels were positively associated with MAFLD and adiponectin levels were inversely associated with MAFLD. The strength of these associations varied according to the different diagnostic criteria for MAFLD.

Elevated alanine transaminase is nonlinearly associated with in-hospital death in ICU-admitted diabetic ketoacidosis patients

AIMS

To investigate the association between alanine transaminase (ALT) and in-hospital death in patients admitted to the intensive care unit for diabetic ketoacidosis (DKA).

METHODS

A cohort of 2,684 patients was constructed from the eICU Collaborative Research Database. Baseline demographic and clinical characteristics were summarized. Cox regressions with restricted cubic spline functions were modelled to explore the association between alanine transaminase and in-hospital death. Subgroup analyses were conducted between sexes, age groups, and people with/without obesity.

RESULTS

After adjusting multiple confounders, a nonlinear, S-shaped association between ALT and in-hospital death was found. Compared to patients at median ALT, patients at the 90th percentile of ALT have a 1.88 (95 % confidence interval [CI]: 1.34-2.62) times higher hazard of in-hospital death in the unstratified cohort. Similar results were found in males (hazard ratio [HR] = 1.69, 95 % CI: 1.24-2.30); patients aged under 65 years (HR = 1.65, 95 % CI: 1.09-2.49); patients aged 65 years or above (HR = 3.45, 95 % CI: 1.67-7.14); non-obese patients (HR = 1.52, 95 % CI: 1.00-2.32); and obese patients (HR = 2.76, 95 % CI: 1.38-5.54).

CONCLUSIONS

Elevated ALT is robustly associated with in-hospital death in ICU-admitted DKA patients across several subgroups. Close monitoring of ALT in these patients is recommended.

Pathophysiology of type 2 diabetes and the impact of altered metabolic interorgan crosstalk

Diabetes is a complex and multifactorial disease that affects millions of people worldwide, reducing the quality of life significantly, and results in grave consequences for our health care system. In type 2 diabetes (T2D), the lack of β-cell compensatory mechanisms overcoming peripherally developed insulin resistance is a paramount factor leading to disturbed blood glucose levels and lipid metabolism. Impaired β-cell functions and insulin resistance have been studied extensively resulting in a good understanding of these pathways but much less is known about interorgan crosstalk, which we define as signaling between tissues by secreted factors. Besides hormones and organokines, dysregulated blood glucose and long-lasting hyperglycemia in T2D is associated with changes in metabolism with metabolites from different tissues contributing to the development of this disease. Recent data suggest that metabolites, such as lipids including free fatty acids and amino acids, play important roles in the interorgan crosstalk during the development of T2D. In general, metabolic remodeling affects physiological homeostasis and impacts the development of T2D. Hence, we highlight the importance of metabolic interorgan crosstalk in this review to gain enhanced knowledge of the pathophysiology of T2D, which may lead to new therapeutic approaches to treat this disease.

Association between Fasting and Postprandial Levels of Liver Enzymes with Metabolic Syndrome and Suspected Prediabetes in Prepubertal Children

Elevated liver enzyme activity may be associated with metabolic syndrome (MetS); however, it is not included in the MetS definition for children. Postprandial changes in the levels of biochemistry tests are related to manifestations of metabolic abnormalities. We assessed the association between fasting and postprandial liver enzymes levels with MetS and elevated hemoglobin A1c (HbA1c) in children aged 9-11. The study included 51 girls and 48 boys, all presumably healthy. In all participants' anthropometric indices, fasting glucose, insulin, lipid profile and HbA1c were measured. Enzymes, including alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT), were assayed in fasting and postprandial states. Individuals were divided into subgroups: with (MetS(+): n = 26); without MetS (MetS(-): n = 73); with HbA1c levels ≤ 5.3% (n = 39); and ≥5.7% (n = 11). Elevated fasting GGT levels were found in 23% of MetS(+) children and rarely in MetS(-) children; increased postprandial GGT was noted in 35% of MetS(+) individuals. Postprandial GGT changes tend to predict MetS (OR = 1.16; p = 0.092). Increased fasting ALT was found rarely in MetS(+) children, but did not occur in MetS(-) children. HbA1c ≥ 5.7% occurred rarely and neither fasting ALT nor GGT were related to elevated HbA1c. However, postprandial change of ALT was a good positive predictor of increased HbA1c (OR = 1.33; p = 0.021). Postprandial GGT performs better as an indicator of metabolic syndrome occurrence, and instead postprandial ALT may predict prediabetes in prepubertal children.

Using hyperhomocysteinemia and body composition to predict the risk of non-alcoholic fatty liver disease in healthcare workers

Purpose

This study investigated associations between serum homocysteine levels, body composition, and the probability of having nonalcoholic fatty liver disease (NAFLD) in Chinese healthcare workers.

Patients and Methods

A total of 4028 healthcare workers were enrolled in this study, and all underwent a physical examination. Body composition was measured using multifrequency bioelectrical impedance analysis.

Results

There were 1507 NAFLD patients (72.26% male, 27.74% female) and 2521 controls (39.83% male, 60.17% female). Body mass index (BMI), waistline, neck-circumference (NC), abdominal visceral fat area (AVFA), total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), glucose (Glu), homocysteinemia (hcy) were higher in the NAFLD group than controls. Additionally, the skeletal-muscle was associated with a lower risk of NAFLD, whereas BMI, waistline, NC, hyperhomocysteinemia (HHcy) were associated with a higher risk of NAFLD. The best NC cut-off point for NAFLD was 34.45 cm (sensitivity 83.3% and specificity 83.9%) in women with HHcy, and the best skeletal-muscle content cut-off point for NAFLD was 41.335% (sensitivity 74.2% and specificity 65.6%) in men with HHcy.

Conclusion

Interactions between skeletal-muscle content, NC, and HHcy may affect the incidence of NAFLD in healthcare workers. This may provide a novel approach for diagnosing NAFLD.

Emerging role for branched-chain amino acids metabolism in fibrosis

Fibrosis is a common pathological feature of organ diseases resulting from excessive production of extracellular matrix, which accounts for significant morbidity and mortality. However, there is currently no effective treatment targeting fibrogenesis. Recently, metabolic alterations are increasingly considered as essential factors underlying fibrogenesis, and especially research on metabolic regulation of amino acids is flourishing. Among them, branched-chain amino acids (BCAAs) are the most abundant essential amino acids, including leucine, isoleucine and valine, which play significant roles in the substance and energy metabolism and their regulation. Dysregulation of BCAAs metabolism has been proven to contribute to numerous diseases. In this review, we summarize the metabolic regulation of fibrosis and the changes in BCAAs metabolism secondary to fibrosis. We also review the effects and mechanisms of the BCAAs intervention, and its therapeutic targeting in hepatic, renal and cardiac fibrosis, with a focus on the fibrosis in liver and associated hepatocellular carcinoma.

The crucial role and mechanism of insulin resistance in metabolic disease

Insulin resistance (IR) plays a crucial role in the development and progression of metabolism-related diseases such as diabetes, hypertension, tumors, and nonalcoholic fatty liver disease, and provides the basis for a common understanding of these chronic diseases. In this study, we provide a systematic review of the causes, mechanisms, and treatments of IR. The pathogenesis of IR depends on genetics, obesity, age, disease, and drug effects. Mechanistically, any factor leading to abnormalities in the insulin signaling pathway leads to the development of IR in the host, including insulin receptor abnormalities, disturbances in the internal environment (regarding inflammation, hypoxia, lipotoxicity, and immunity), metabolic function of the liver and organelles, and other abnormalities. The available therapeutic strategies for IR are mainly exercise and dietary habit improvement, and chemotherapy based on biguanides and glucagon-like peptide-1, and traditional Chinese medicine treatments (e.g., herbs and acupuncture) can also be helpful. Based on the current understanding of IR mechanisms, there are still some vacancies to follow up and consider, and there is also a need to define more precise biomarkers for different chronic diseases and lifestyle interventions, and to explore natural or synthetic drugs targeting IR treatment. This could enable the treatment of patients with multiple combined metabolic diseases, with the aim of treating the disease holistically to reduce healthcare expenditures and to improve the quality of life of patients to some extent.

Human CYP2B6 produces oxylipins from polyunsaturated fatty acids and reduces diet-induced obesity

Multiple factors in addition to over consumption lead to obesity and non-alcoholic fatty liver disease (NAFLD) in the United States and worldwide. CYP2B6 is the only human detoxification CYP whose loss is associated with obesity, and Cyp2b-null mice show greater diet-induced obesity with increased steatosis than wildtype mice. However, a putative mechanism has not been determined. LC-MS/MS revealed that CYP2B6 metabolizes PUFAs, with a preference for metabolism of ALA to 9-HOTrE and to a lesser extent 13-HOTrE with a preference for metabolism of PUFAs at the 9- and 13-positions. To further study the role of CYP2B6 in vivo, humanized-CYP2B6-transgenic (hCYP2B6-Tg) and Cyp2b-null mice were fed a 60% high-fat diet for 16 weeks. Compared to Cyp2b-null mice, hCYP2B6-Tg mice showed reduced weight gain and metabolic disease as measured by glucose tolerance tests, however hCYP2B6-Tg male mice showed increased liver triglycerides. Serum and liver oxylipin metabolite concentrations increased in male hCYP2B6-Tg mice, while only serum oxylipins increased in female hCYP2B6-Tg mice with the greatest increases in LA oxylipins metabolized at the 9 and 13-positions. Several of these oxylipins, specifically 9-HODE, 9-HOTrE, and 13-oxoODE, are PPAR agonists. RNA-seq data also demonstrated sexually dimorphic changes in gene expression related to nuclear receptor signaling, especially CAR > PPAR with qPCR suggesting PPARγ signaling is more likely than PPARα signaling in male mice. Overall, our data indicates that CYP2B6 is an anti-obesity enzyme, but probably to a lesser extent than murine Cyp2b's. Therefore, the inhibition of CYP2B6 by xenobiotics or dietary fats can exacerbate obesity and metabolic disease potentially through disrupted PUFA metabolism and the production of key lipid metabolites.

Adiponectin alleviates non-alcoholic fatty liver injury via regulating oxidative stress in liver cells

BACKGROUND

The aim of the present study was to investigate the role of adiponectin in non-alcoholic fatty liver cell model and its mechanism.

METHODS

The serum were collected from patients with non-alcoholic fatty liver disease and healthy controls. Then the expression of APN in the serum was detected using APN kit. Furthermore, an in vitro model of NAFLD was established using mixed fatty acids treated HepG2 cells, and APN was highly expressed in the culture solution to a concentration of 10 μg/mL. The normal control group (Normal) was normal cells, the model group (NAFLD) was mixed fatty acids treated HepG2 cells, the experimental group (NAFLD+APN) was model cells transfected with high APN expression, and the negative control group (NAFLD+PBS) was model cells transfected with PBS. The expression of NOX2 in each group was detected by Western blot. The corresponding kit was used to detect the level of triglyceride (TG), the activity of superoxide dismutase (SOD), the content of malondialdehyde (MDA), and the ratio of GSH/GSSG in each group of cells.

RESULTS

The expression level of APN was greatly decreased in the serum of NAFLD patients (P<0.01), and the TG content was significantly increased in HepG2 cells treated with fatty acids (P<0.001), indicating successful modeling. The cells had high expression of APN (P<0.001) showed low expression of NOX2 (P<0.001). The kit test results showed that the high expression of APN could reverse the decrease of SOD activity, the increase of MDA level, the decrease of GSH/GSSG ratio and the increase of TG content (P<0.001), all of which were restored to the modeling level after application of NOX2's activator TBCA.

CONCLUSIONS

APN was lowly expressed in the serum of NAFLD patients. Its effect mechanism was to alleviate the injury of NAFLD cells by reducing oxidative stress via regulating NOX2 expression.

Diabetes medications and risk of HCC

Type 2 diabetes mellitus is a recognized risk factor for HCC in patients with liver disease, independent from the etiology of their liver disease. Hence, prevention and treatment of type 2 diabetes mellitus and its underlying cause, insulin resistance, should be considered a treatment target for patients with liver disease. The drug armamentarium for diabetes is wide and consists of agents with insulin-sensitizing activity, agents that stimulate insulin secretion, insulin itself, and agents that reduce gastrointestinal and urinary glucose absorption. From an endocrinology perspective, the main goal of treatment is the achievement of euglycemia; however, in patients at risk of, or with known underlying liver disease, the choice of diabetic medication as it relates to potential hepatic carcinogenesis remains complex and should be carefully considered. In the last decade, increasing evidence has suggested that metformin may reduce the risk of HCC, whereas evidence for other classes of diabetic medications, particularly some of the newer agents including the sodium glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists, is fewer and often inconsistent. In this review, we aim to summarize the current evidence on the potential effects of the most widely used diabetic agents on liver cancer tumorigenesis.