Prevalence and clinical outcomes in subtypes of metabolic associated fatty liver disease

BACKGROUND/PURPOSE

In 2020, metabolic Associated Fatty Liver Disease (MAFLD) was proposed to replace non-alcoholic fatty liver disease (NAFLD) with new diagnostic criteria. The prevalence and clinical outcomes of MAFLD subtypes remained unclear.

METHODS

The participants from Taiwan bio-bank cohort were included. MAFLD was defined as the presence of fatty liver, plus any of the following three conditions: overweight/obesity, diabetes mellitus (DM), or metabolic dysfunction. The patients with positive HBsAg or anti-HCV were considered as chronic HBV or HCV infection. NAFLD fibrosis score (NFS) > 0.676 plus fibrosis 4 (FIB-4) score > 2.67 was defined as advanced liver fibrosis. Atherosclerosis was diagnosed as having carotid plaques on duplex ultrasounds. The clinical outcomes were assessed among four subtypes of MAFLD including DM, obesity, chronic HBV infection, and chronic HCV infection.

RESULTS

A total of 21,885 participants (mean age 55.34 ± 10.31; 35.69% males) were included in the final analysis. Among them, 38.83% were diagnosed with MAFLD. The prevalence of MAFLD was 66.95% in DM patients, 65.07% in obese participants, 33.74% in chronic HBV patients, and 30.23% in chronic HCV patients. Logistic regression analysis showed that the subtypes of DM and chronic HCV infection were associated with an increased risk of advanced liver fibrosis in MAFLD patients. Additionally, the subtypes of DM and lean were associated with an increased risk of atherosclerosis, but a decreased risk of atherosclerosis in the subtype of chronic HBV infection.

CONCLUSION

This population-based study proves the concept that subtypes of MAFLD can help risk stratification of clinical outcomes.

The Independent Association of Non-alcoholic Fatty Liver Disease With Incident Cardiovascular Disease: A GRADE Evaluation of the Evidence Through a Systematic Review and Meta-analysis

BACKGROUND

We conducted a systematic review and meta-analysis to study the association between non-alcoholic fatty liver disease (NAFLD) and incident cardiovascular disease (CVD).

METHODS

We searched Medline, Embase, Cochrane database and TRIP database. Random-effects model meta-analyses were used to obtain pooled effect sizes and 95% confidence intervals. The certainty in evidence was rated using the GRADE tool.

RESULTS

Altogether 36 studies including a total of 7,068,007 participants were included in the systematic review and meta-analysis. Pooled data from 19 cohort studies demonstrated a significant increase in the risk of non-fatal CVD events in patients with NAFLD (HR 1.57, 95% CI 1.33-1.85, I2 = 95%). Pooled data from eight studies showed a significant increase in fatal CVD (HR 1.40, 95% CI 1.24-1.57, I2 =27%), and eight cohort studies suggested a significant increase in combined non-fatal and fatal CVD (HR 1.41, 95% CI 1.13-1.76, I2 =80%). Meta-analysis of studies reporting adjusted estimates in NAFLD patients with fibrosis revealed a significant increase in CVD events with acceptable level of heterogeneity (HR 1.64, 95% CI 1.25-2.16, I2 = 31%). The anticipated absolute increase in the risk of combined fatal and non-fatal CVD was estimated to be 29 more per thousand with NAFLD; that of fatal CVD events 16 more per thousand and that of non-fatal CVD events 19 more per thousand with NAFLD. The GRADE rating ranged from very low to low for overall and subgroup analyses.

CONCLUSION

The present systematic review suggests that NAFLD increases the risk of incident CVD. Cohort studies with the ability to analyze subgroup effects based on severity, along with randomized controlled trials that provide experimental evidence demonstrating a decrease in cardiovascular disease events through the treatment of non-alcoholic fatty liver disease, are necessary to validate and reinforce these findings.

The Definition and Prevalence of Obesity and Metabolic Syndrome: Correlative Clinical Evaluation Based on Phenotypes

Increase in the prevalence of obesity has become a major worldwide health problem in adults as well as among children and adolescents. In the last four decades, studies have revealed that the significant increase in the prevalence of obesity has become a pandemic. Obesity is the result of complex interactions between biological, genetic, environmental, and behavioral factors. Indeed, almost all of the children suffering from obesity in early childhood face with being overweight or obese in adolescence. Different phenotypes have different risk factors in the clinical evaluation of obesity. Individuals suffering from metabolically unhealthy obesity (MUO) are at an excess risk of developing cardiovascular diseases (CVDs), several cancer types, and metabolic syndrome (MetS), whereas the metabolically healthy obesity (MHO) phenotype has a high risk of all-cause mortality and cardiometabolic events but not MetS. While most obese individuals have the MUO phenotype, the frequency of the MHO phenotype is at most 10-20%. Over time, approximately three-quarters of obese individuals transform from MHO to MUO. Total adiposity and truncal subcutaneous fat accumulation during adolescence are positively and independently associated with atherosclerosis in adulthood. Obesity, in general, causes a large reduction in life expectancy. However, the mortality rate of morbid obesity is greater among younger than older adults. Insulin resistance (IR) develops with the central accumulation of body fat. MHO patients are insulin-sensitive like healthy normal-weight individuals and have lower visceral fat content and cardiovascular consequences than do the majority of MUO patients. MetS includes clustering of abdominal obesity, dyslipidemia, hyperglycemia, and hypertension. The average incidence of MetS is 3%, with a 1.5-fold increase in the risk of death from all causes in these patients. If lifestyle modifications, dietary habits, and pharmacotherapy do not provide any benefit, then bariatric surgery is recommended to reduce weight and improve comorbid diseases. However, obesity treatment should be continuous in obese patients by monitoring the accompanying diseases and their consequences. In addition to sodium-glucose co-transporter-2 (SGLT2) inhibitors, the long-acting glucagon-like peptide-1 (GLP-1) receptor agonist reduces the mean body weight. However, caloric restriction provides more favorable improvement in body composition than does treatment with the GLP-1 receptor (GLP1R) agonist alone. Combination therapy with orlistat and phentermine are the US Food and Drug Administration (FDA)-approved anti-obesity drugs. Recombinant leptin and synthetic melanocortin-4-receptor agonists are used in rarely occurring, monogenic obesity, which is due to loss of function in the leptin-melanocortin pathway.

Application and Diagnostic Performance of Two-Dimensional Shear Wave Elastography and Liver Fibrosis Scores in Adults with Class 3 Obesity

There are no ideal non-invasive tests for assessing the severity of liver fibrosis in people with metabolic dysfunction-associated steatotic liver disease (MASLD) and class 3 obesity, where body habitus often makes imaging technically challenging. This study aimed to assess the applicability and diagnostic performance of two-dimensional shear wave elastography (2D-SWE), alongside several serum-based liver fibrosis scoring methods, in individuals with class 3 obesity. A cross-sectional study was conducted in patients aged ≥18 years and with a body mass index (BMI) ≥ 40 kg/m2 who were participants in a publicly funded multidisciplinary weight management program in South Western Sydney. The 2D-SWE was performed using the ElastQ Imaging (EQI) procedure with the Phillips EPIQ Elite series ultrasound. An EQI Median value of ≥6.43 kPa was taken as a cutoff score for significant fibrosis, and the scan was considered valid when the liver EQI IQR/Med value was <30%. The Fibrosis-4 (FIB-4) index, AST-to-platelet ratio index (APRI), NAFLD fibrosis score (NFS), and circulating fibroblast activation protein index (FAP index) were calculated from fasting blood samples. The participants (n = 116; 67.2% female) were aged 47.2 ± 12.9 years, with BMI 54.5 ± 11.0 kg/m2. EQI Median values were obtained for 97.4% (113/116) of the 2D-SWE scans, and 91.4% (106/116) of the scans were considered valid. The EQI Median values exhibited a moderately positive correlation with the FIB-4 index (r = 0.438; p < 0.001) and a weakly positive correlation with the APRI (r = 0.388; p < 0.001), NFS (r = 0.210; p = 0.036) and FAP index (r = 0.226; p = 0.020). All liver fibrosis scores were positively correlated with one another. Among those referred for a liver biopsy based on the 2D-SWE and serum scores, half (11/22) underwent liver biopsy, and their 2D-SWE scores exhibited 72.7% accuracy (sensitivity: 71.4%; specificity: 75%) in detecting significant fibrosis. Our results show that 2D-SWE is a feasible, non-invasive test to assess liver fibrosis among people with class 3 obesity. Further research is needed to assess how 2D-SWE can be used alongside existing serum-based risk scores to reliably detect significant fibrosis, which would potentially reduce the need for invasive liver biopsy.

Hepatic Huwe1 loss protects mice from non-alcoholic fatty liver disease through lipid metabolic rewiring

Non-alcoholic fatty liver disease (NAFLD) is the most pervasive liver pathology worldwide. Here, we demonstrate that the ubiquitin E3 ligase Huwe1 is vital in NAFLD pathogenesis. Using mass spectrometry and RNA sequencing, we reveal that liver-specific deletion of Huwe1 (Huwe1LKO) in 1-year-old mice (approximately middle age in humans) elicits extensive lipid metabolic reprogramming that involves downregulation of de novo lipogenesis and fatty acid uptake, upregulation of fatty acid β-oxidation, and increased oxidative phosphorylation. ChEA transcription factor prediction analysis inferred these changes result from attenuated PPARɑ, LXR, and RXR activity in Huwe1LKO livers. Consequently, Huwe1LKO mice fed chow diet exhibited significantly reduced hepatic steatosis and superior glucose tolerance compared to wild-type mice. Huwe1LKO also conferred protection from high-fat diet-induced hepatic steatosis by 6-months of age, with increasingly robust differences observed as mice reached middle age. Together, we present evidence that Huwe1 plays a critical role in the development of age- and diet-induced NAFLD.

Thyroid Hormone and Mitochondrial Dysfunction: Therapeutic Implications for Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly termed nonalcoholic fatty liver disease (NAFLD), is a widespread global health concern that affects around 25% of the global population. Its influence is expanding, and it is anticipated to overtake alcohol as the leading cause of liver failure and liver-related death worldwide. Unfortunately, there are no approved therapies for MASLD; as such, national and international regulatory health agencies undertook strategies and action plans designed to expedite the development of drugs for treatment of MASLD. A sedentary lifestyle and an unhealthy diet intake are important risk factors. Western countries have a greater estimated prevalence of MASLD partly due to lifestyle habits. Mitochondrial dysfunction is strongly linked to the development of MASLD. Further, it has been speculated that mitophagy, a type of mitochondrial quality control, may be impaired in MASLD. Thyroid hormone (TH) coordinates signals from the nuclear and mitochondrial genomes to control mitochondrial biogenesis and function in hepatocytes. Mitochondria are known TH targets, and preclinical and clinical studies suggest that TH, thyroid receptor β (TR-β) analogs, and synthetic analogs specific to the liver could be of therapeutic benefit in treating MASLD. In this review, we highlight how mitochondrial dysfunction contributes to development of MASLD, and how understanding the role of TH in improving mitochondrial function paved the way for innovative drug development programs of TH-based therapies targeting MASLD.

Old age as a risk factor for liver diseases: Modern therapeutic approaches

Recent scientific interest has been directed towards age-related diseases, driven by the significant increase in global life expectancy and the growing population of individuals aged 65 and above. The ageing process encompasses various biological, physiological, environmental, psychological, behavioural, and social changes, leading to an augmented susceptibility to chronic illnesses. Cardiovascular, neurological, musculoskeletal, liver and oncological diseases are prevalent in the elderly. Moreover, ageing individuals demonstrate reduced regenerative capacity and decreased tolerance towards therapeutic interventions, including organ transplantation. Liver diseases, such as non-alcoholic fatty liver disease, alcoholic liver disease, hepatitis, fibrosis, and cirrhosis, have emerged as significant public health concerns. Paradoxically, these conditions remain underestimated despite their substantial global impact. Age-related factors are closely associated with the severity and unfavorable prognosis of various liver diseases, warranting further investigation to enhance clinical management and develop novel therapeutic strategies. This comprehensive review focuses specifically on age-related liver diseases, their treatment strategies, and contemporary practices. It provides a detailed account of the global burden, types, molecular mechanisms, and epigenetic alterations underlying these liver pathologies.

Prevalence of non-alcoholic fatty liver in the general Dutch population and in groups at increased risk

BACKGROUND AND AIM

Non-alcoholic fatty liver disease (NAFLD) is defined as a liver fat content ≥5.56%. It is of clinical interest to know the prevalence of NAFLD in people with a combination of metabolic risk factors. We aimed to examine the prevalence of NAFLD, including groups with metabolic risk factors.

METHODS AND RESULTS

In this cross-sectional analysis of the Netherlands Epidemiology of Obesity (NEO) study, liver fat content was assessed using proton magnetic resonance spectroscopy (H-MRS). Participants with excessive alcohol consumption or missing values were excluded, leaving a total of 1570 participants for the analyses. Mean (SD) age of the population was 55 years, BMI 25.9 (4.0) kg/m2 and 46% were men. The prevalence of NAFLD was 27% (95% CI 24-30). The prevalence of NAFLD was increased in participants with hypertriglyceridemia (57%, 52-63), obesity (62%, 58-66) and diabetes (69%, 61-77). The prevalence of NAFLD was highest in those with diabetes and obesity (79%, 71-87), obesity and hypertriglyceridemia (81%, 76-86) and with diabetes and hypertriglyceridemia (86%, 77-95). NAFLD was also present in 12% (8-16) of participants without overweight.

CONCLUSIONS

The prevalence of NAFLD in a middle-aged population in the Netherlands in 2010 was 27%. The prevalence of NAFLD is particularly increased in individuals with diabetes, obesity, and hypertriglyceridemia. This information may help clinicians and general practitioners in the risk stratification of their patients in daily practice.

Detection of Moderate Hepatic Steatosis on Portal Venous Phase Contrast-Enhanced CT: Evaluation Using an Automated Artificial Intelligence Tool

BACKGROUND. Precontrast CT is an established means of evaluating for hepatic steatosis; postcontrast CT has historically been limited for this purpose. OBJECTIVE. The purpose of this study was to evaluate the diagnostic performance of portal venous phase postcontrast CT in detecting at least moderate hepatic steatosis using liver and spleen attenuation measurements determined by an automated artificial intelligence (AI) tool. METHODS. This retrospective study included 2917 patients (1381 men, 1536 women; mean age, 56.8 years) who underwent a CT examination that included at least two series through the liver. Examinations were obtained from an AI vendor's data lake of data from 24 centers in one U.S. health care network and 29 centers in one Israeli health care network. An automated deep learning tool extracted liver and spleen attenuation measurements. The reference for at least moderate steatosis was precontrast liver attenuation of less than 40 HU (i.e., estimated liver fat > 15%). A radiologist manually reviewed examinations with outlier AI results to confirm portal venous timing and identify issues impacting attenuation measurements. RESULTS. After outlier review, analysis included 2777 patients with portal venous phase images. Prevalence of at least moderate steatosis was 13.9% (387/2777). Patients without and with at least moderate steatosis, respectively, had mean postcontrast liver attenuation of 104.5 ± 18.1 (SD) HU and 67.1 ± 18.6 HU (p < .001); a mean difference in postcontrast attenuation between the liver and the spleen (hereafter, postcontrast liver-spleen attenuation difference) of -7.6 ± 16.4 (SD) HU and -31.8 ± 20.3 HU (p < .001); and mean liver enhancement of 49.3 ± 15.9 (SD) HU versus 38.6 ± 13.6 HU (p < .001). Diagnostic performance for the detection of at least moderate steatosis was higher for postcontrast liver attenuation (AUC = 0.938) than for the postcontrast liver-spleen attenuation difference (AUC = 0.832) (p < .001). For detection of at least moderate steatosis, postcontrast liver attenuation had sensitivity and specificity of 77.8% and 93.2%, respectively, at less than 80 HU and 90.5% and 78.4%, respectively, at less than 90 HU; the postcontrast liver-spleen attenuation difference had sensitivity and specificity of 71.4% and 79.3%, respectively, at less than -20 HU and 87.0% and 62.1%, respectively, at less than -10 HU. CONCLUSION. Postcontrast liver attenuation outperformed the postcontrast liver-spleen attenuation difference for detecting at least moderate steatosis in a heterogeneous patient sample, as evaluated using an automated AI tool. Splenic attenuation likely is not needed to assess for at least moderate steatosis on postcontrast images. CLINICAL IMPACT. The technique could promote early detection of clinically significant nonalcoholic fatty liver disease through individualized or large-scale opportunistic evaluation.

Alleviation of adipose-hepatic glycolipid dysregulation by acetate in experimental PCOS model is associated with NF-κB/NLRP3 repression

This study hypothesized that acetate breaks the vicious cycle driving adipose-hepatic metabolic dysregulation in a rat model of polycystic ovarian syndrome (PCOS), possibly by suppression of nuclear factor-kappaB (NF-κB)/NOD-like receptor protein 3 (NLRP3) inflammasome. Female Wistar rats (8-week-old) were randomly allocated into four groups of n =6/group, which received vehicle, sodium acetate (200 mg), letrozole (1 mg/kg), and letrozole plus sodium acetate, respectively. The animals were treated by oral gavage, once daily for a period of 21 days. The PCOS animals were insulin-resistant, hyperandrogenic, and hypoestrogenic with decreased sex-hormone binding globulin. In addition, the hepatic tissue had increased lipid profile and decreased glycogen synthesis, while the adipose tissue showed decreased lipid profile with elevated glycogen synthesis. Besides, the results also showed increased malondialdehyde, γ-glutamyl transferase, lactate dehydrogenase, and inflammatory mediators with corresponding decrease in antioxidant defense in the hepatic and adipose tissues. Immunohistochemical evaluation also demonstrated severe expression with Bcl2-associated X protein/NLRP3 antibodies. Nonetheless, concomitant acetate supplementation attenuated these derangements. The present data collectively suggest that acetate ameliorates adipose-hepatic glycolipid dysregulation in experimental PCOS model by attenuating androgen excess and NF-κB/NLRP3 immunoreactivity.

Noninvasive biomarkers of non-alcoholic fatty liver disease in patients with metabolic syndrome: insights from the RESOLVE Study

BACKGROUND

The aim of the present study was to evaluate: 1) the presence of liver steatosis using Fatty Liver Index (FLI), Hepatic Steatosis Index (HSI) and Liver Fat Score (LFS) in patients suffering from metabolic syndrome (MS); and 2) the association of FLI, HSI and LFS with the cardiometabolic risks.

METHODS

A total of 91 patients with MS (39 men, 52 women) and 44-age matched healthy subjects (control; 23 men and 21 women) were enrolled in the study. A continuous cardiometabolic score (MetsScore) and the noninvasive tests of hepatic steatosis were calculated for comparison and association analysis.

RESULTS

Liver steatosis was detected in 86%, 84% and 80% of people diagnosed with MS using FLI, HSI and LFS respectively and MetsScore increases with FLI severity (P<0.05). Also, FLI and LFS were positively associated with MetsScore (P<0.01 and P<0.05 respectively) but not HSI. Multivariate linear regression models revealed that FLI has a stronger association with MetsScore compared with HSI and LFS (P<0.001).

CONCLUSIONS

FLI is associated with the severity of MS and represent a good indicator to assess the relation between liver steatosis and a cardiometabolic disorders in clinical routine.

Kidney damage predictors in children with metabolically healthy and metabolically unhealthy obesity phenotype

BACKGROUND

Obesity and kidney damage have been closely linked in adults, but little is still known in childhood.

OBJECTIVE

To identify predictors of kidney damage in children with metabolically healthy (MHO) and metabolically unhealthy (MUO) obesity phenotypes.

METHODS

We retrospectively examined 396 children with obesity (mean age 10.72 ± 2.71 years, body mass index-standard deviation score, BMI-SDS, 2.23 ± 0.57) stratified according to metabolic phenotypes. Kidney damage was defined as the presence of reduced estimated glomerular filtration rate (eGFR < 90 mL/min/1.73m2) and/or albuminuria (≥ 30 mg/g urinary creatinine).

RESULTS

Kidney damage was found in 20.9% of the study population. Children with kidney damage had higher BMI-SDS, homeostasis model assessment of insulin resistance (HOMA-IR), and inflammation markers levels and increased prevalence of non-alcoholic fatty liver disease (NAFLD) than those without kidney damage (all p < 0.005). MUO and MHO subjects had respectively an odds ratio (OR) to show kidney damage of of 1.92 (95%CI:1.22-3.01; p = 0.005) and 1.05 (95%CI:1.00-1.09; p = 0.028) after adjustments. Moreover, we found that only HOMA-IR was closely associated to kidney damage in MUO group (OR = 2.07;95%CI:1.20-3.57; p = 0.007), while HOMA-IR (OR = 1.15;95%CI:1.02-1.29; p = 0.011) and uric acid (OR = 1.15;95% CI:1.02-1.30; p = 0.010) were the only significant risk factors for kidney damage in MHO group.

CONCLUSION

An increased risk of kidney damage has been observed in children with obesity and in particular in those with MUO phenotype. As their role on kidney function, HOMA-IR should be monitored in MUO children and both HOMA-IR and uric acid in MHO children.

HbA1c of 5.8% or higher as the most useful indicator for recommendation of ultrasonography to detect nonalcoholic fatty liver disease

Background and Aim

Nonalcoholic fatty liver disease (NAFLD) is closely associated with metabolic syndrome. This study was performed to examine the association between NAFLD and each factor of metabolic syndrome and to identify the factors that are most strongly associated with NAFLD in participants undergoing health checkups.

Methods

We studied 6538 participants who underwent a health checkup from 2017 to 2018 in our institution. Participants with alcohol intake exceeding 20 g/day or with other chronic liver diseases were excluded. Fatty liver was detected by ultrasonography.

Results

In total, 4310 participants were enrolled, and 28.4% had fatty liver (NAFLD). The prevalence of NAFLD was highest in the diabetes mellitus (DM)-only group than in the dyslipidemia-only or hypertension-only group. The DM-only group was the only group whose prevalence of NAFLD was >50% in the overall study and in males. The prevalence of NAFLD was higher in males than in females in the DM-only, hypertension-only, and dyslipidemia-only groups. The prevalence of NAFLD was >70% in the dyslipidemia and DM combined group. Multivariate analysis showed that gender and HbA1c were the independent factors most strongly associated with NAFLD. The cutoff value for HbA1c by receiver operating characteristic curve analysis was 5.8% (sensitivity, 57.9%; specificity, 72.6%; area under the curve, 0.70).

Conclusion

NAFLD was most strongly associated with DM, among the various components of metabolic syndrome. We strongly recommend abdominal ultrasonography to detect NAFLD in patients with an HbA1c of ≥5.8% in general practice and during health checkups.

Decoding clinical and molecular pathways of liver dysfunction in Psoriatic Arthritis: Impact of cumulative methotrexate doses

BACKGROUND

The occurrence of liver abnormalities in Psoriatic Arthritis (PsA) has gained significant recognition. Identifying key factors at the clinical and molecular level can help to detect high-risk patients for non-alcoholic fatty liver disease in PsA.

OBJECTIVES

to investigate the influence of PsA and cumulative doses of methotrexate on liver function through comprehensive in vivo and in vitro investigations.

METHODS

A cross-sectional study involving 387 subjects was conducted, 200 patients with PsA, 87 NAFLD-non-PsA patients, and 100 healthy donors (HDs), age and sex-matched. Additionally, a retrospective longitudinal study was carried out, including 83 PsA patients since initiation with methotrexate. Detailed clinical, and laboratory parameters along with liver disease risk were analyzed. In vitro, experiments with hepatocyte cell line (HEPG2) were conducted.

RESULTS

PsA patients present increased liver disease risk associated with the presence of cardiometabolic comorbidities, inflammatory markers, onychopathy, and psoriasis. The treatment with PsA serum on hepatocytes encompassed inflammatory, fibrotic, cell stress, and apoptotic processes. At the molecular level, methotrexate impacts liver biology, although the cumulative doses did not affect those alterations, causing any potential damage to liver function at the clinical level. Finally, anti-PDE-4 or anti-JAK decreased the inflammatory profile induced by PsA serum on hepatocytes.

CONCLUSION

1)This study identifies the complex link between liver disease risk, comorbidities, and disease-specific features in PsA patients. 2)Methotrexate dose in PsA patients had no significant effect on liver parameters, confirmed by hepatocyte in vitro studies. 3)Anti-PDE-4 and anti-JAK therapies show promise in reducing PsA serum-induced hepatocyte activation, potentially aiding liver complication management.

Higher oxidative balance scores are associated with lower nonalcoholic fatty liver disease and not with fibrosis in US adults

BACKGROUND AND AIMS

Little research have focused on the relationship between systemic oxidative stress status and NAFLD and fibrosis. The Oxidative Balance Score (OBS) is employed to evaluate whole-body lifestyle and diet exposures related to oxidative stress, with higher OBS scores implying exposure to more antioxidants. This study aimed to explore whether OBS is correlated with NAFLD and NAFLD-related fibrosis.

METHODS AND RESULTS

12,223 participants from NHANES 2003-2018 were enrolled in this study. NAFLD was defined as USFLI ≥30 and liver fibrosis was determined as FIB-4 ≥ 2.67. OBS was scored by 20 lifestyle and dietary factors. Weighted logistic regression and restricted cubic splines were used to assess the association between OBS and NAFLD and fibrosis. The prevalence of NAFLD was 29.67%. There was a significant negative correlation between OBS, dietary OBS, lifestyle OBS and NAFLD and no correlation with NAFLD-related fibrosis. Compared to the lowest quartile, the adjusted ORs for the highest quartile of OBS, lifestyle OBS, dietary OBS and NAFLD were 0.55(95%CI:0.35,0.85), 0.12(95%CI:0.08,0.16), 0.70(95%CI:0.52,0.94) respectively. In stratified analyses, lifestyle OBS was negatively associated with NAFLD across gender, dietary OBS was only negatively correlated with NAFLD in men, and any OBS was not observed to be relevant to NAFLD-related fibrosis.

CONCLUSIONS

OBS was negatively associated with NAFLD, but not with NAFLD-related fibrosis. The findings underline the significance of adhering to an antioxidant lifestyle and diet, which can help prevent NAFLD but seems to be ineffective in preventing fibrosis in individuals with NAFLD.

Quantification of ectopic fat storage in the liver and pancreas using six-point Dixon MRI and its association with insulin sensitivity and β-cell function in patients with central obesity

OBJECTIVES

To assess the association of ectopic fat deposition in the liver and pancreas quantified by Dixon magnetic resonance imaging (MRI) with insulin sensitivity and β-cell function in patients with central obesity.

MATERIALS AND METHODS

A cross-sectional study of 143 patients with central obesity with normal glucose tolerance (NGT), prediabetes (PreD), and untreated type 2 diabetes mellitus (T2DM) was conducted between December 2019 and March 2022. All participants underwent routine medical history taking, anthropometric measurements, and laboratory tests, including a standard glucose tolerance test to quantify insulin sensitivity and β-cell function. The fat content in the liver and pancreas was measured with MRI using the six-point Dixon technique.

RESULTS

Patients with T2DM and PreD had a higher liver fat fraction (LFF) than those with NGT, while those with T2DM had a higher pancreatic fat fraction (PFF) than those with PreD and NGT. LFF was positively correlated with homeostatic model assessment of insulin resistance (HOMA-IR), while PFF was negatively correlated with homeostatic model assessment of insulin secretion (HOMA-β). Furthermore, using a structured equation model, we found LFF and PFF to be positively associated with glycosylated hemoglobin via HOMA-IR and HOMA-β, respectively.

CONCLUSIONS

In patients with central obesity, the effects of LFF and PFF on glucose metabolism. were associated with HOMA-IR and HOMA-β, respectively. Ectopic fat storage in the liver and pancreas quantified by MR Dixon imaging potentially plays a notable role in the onset ofT2DM.

CLINICAL RELEVANCE STATEMENT

We highlight the potential role of ectopic fat deposition in the liver and pancreas in the development of type 2 diabetes in patients with central obesity, providing valuable insights into the pathogenesis of the disease and potential targets for intervention.

KEY POINTS

• Ectopic fat deposition in the liver and pancreas is associated with T2DM. • T2DM and prediabetes patients had higher liver and pancreatic fat fractions than normal individuals. • The results provide valuable insights into pathogenesis of T2DM and potential targets for intervention.

Endocrine aspects of metabolic dysfunction-associated steatotic liver disease (MASLD): Beyond insulin resistance

While the association of metabolic dysfunction-associated steatotic liver disease (MASLD) with obesity and insulin resistance is widely appreciated, there are a host of complex interactions between the liver and other endocrine axes. While it can be difficult to definitively distinguish direct causal relationships and those attributable to increased adipocyte mass, there is substantial evidence of the direct and indirect effects of endocrine dysregulation on the severity of MASLD, with strong evidence that low levels of growth hormone, sex hormones, and thyroid hormone promote the development and progression of disease. The impact of steroid hormones, e.g. cortisol and dehydroepiandrosterone, and adipokines is much more divergent. Thoughtful assessment, based on individual risk factors and findings, and management of non-insulin endocrine axes is essential in the evaluation and management of MASLD. Multiple therapeutic options have emerged that leverage various endocrine axes to reduce the fibroinflammatory cascade in MASH.

Circ_0004535/miR-1827/CASP8 network involved in type 2 diabetes mellitus with nonalcoholic fatty liver disease

Diagnostic delay in type 2 diabetes mellitus (T2DM) with nonalcoholic fatty liver disease (NAFLD) patients often leads to a serious public health problem. Understanding the pathophysiological mechanisms of disease will help develop more effective treatments. High-throughput sequencing was used to determine the expression levels of circRNAs, and mRNAs in health controls, T2DM patients, and T2DM with NAFLD patients. Differentially expressed genes (DEcircRs, DEmRs) in T2DM with NAFLD were identified by differential analysis. The miRNAs with targeted relationship with the DEcircRs and DEmRs were respectively predicted to construct a ceRNA regulatory network. In addition, enrichment analysis of DEmRs in the ceRNA network was performed. The expression of important DEcircRs was further validated by quantitative real-time PCR (qRT-PCR). The steatosis was detected in glucose treated LO2 cells by overexpressing circ_0004535, and CASP8. There were 586 DEmRs, and 10 DEcircRs in both T2DM and T2DM with NAFLD patients. Combined with predicted results and differential analysis, the ceRNA networks were constructed. The DEmRs in the ceRNA networks were mainly enriched in Toll-like receptor signaling pathway, and apoptosis. Importantly, dual luciferase experiments validated the targeted binding of hsa_circ_0004535 and hsa-miR-1827 or hsa-miR-1827 and CASP8. qRT-PCR experiments validated that hsa_circ_0004535, and CASP8 was downregulated and hsa-miR-1827 was upregulated expression in peripheral blood of T2DM with NAFLD patients. Abnormal cell morphology, and increased lipid droplet fusion were observed in the glucose treated LO2 cells, overexpression of circ_0004535 and CASP8 ameliorated these changes. Our work provides a deeper understanding of ceRNA mediated pathogenesis of T2DM with NAFLD and provides a novel strategy for treatment.

Fatty liver disease that is neither metabolic nor alcoholic

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. This article aims to summary less common etiologies of fatty liver and their key clinicopathological features.

Metabolic-associated fatty liver disease is associated with colorectal adenomas in young and older Korean adults

BACKGROUND AND AIMS

Given that the majority of colorectal cancers (CRCs) develop from high-risk adenomas, identifying risk factors for high-risk adenomas is important. The relationship between metabolic dysfunction-associated fatty liver disease (MAFLD) and the risk of colorectal adenoma in young adults remains unclear. We aimed to evaluate this relationship in adults <50 (younger) and ≥50 (older) years of age.

METHODS

This cross-sectional study included 184 792 Korean adults (80% <50 years of age) who all underwent liver ultrasound and colonoscopy. Participants were grouped into those with and without MAFLD and classified by adenoma presence into no adenoma, low-risk adenoma, or high-risk adenoma (defined as ≥3 adenomas, any ≥10 mm, or adenoma with high-grade dysplasia/villous features).

RESULTS

The prevalence of low- and high-risk adenomas among young and older adults was 9.6% and 0.8% and 22.3% and 4.8%, respectively. MAFLD was associated with an increased prevalence of low- and high-risk adenomas in young and older adults. Young adults with MAFLD had a 1.30 (95% CIs 1.26-1.35) and 1.40 (1.23-1.59) times higher prevalence of low- and high-risk adenomas, respectively, compared to those without MAFLD. These associations were consistent even in lean adults (BMI < 23 kg/m2 ) and those without a family history of CRC.

CONCLUSIONS

MAFLD is associated with an increased prevalence of low- and high-risk adenomas in Korean adults, regardless of age or obesity status. Whether reducing metabolic risk factors, such as MAFLD, reduces the risk of precancerous lesions and ultimately reduces the risk of early-onset CRC requires further investigation.

A short-term high-sugar diet is an aggravating factor in experimental allergic contact dermatitis

Allergic contact dermatitis (ACD) is an inflammatory skin reaction whose incidence has increased and has been associated with a dietary pattern rich in saturated fats and refined sugars. Considering the increased incidence of ACD and the lack of research about the influence of a short-term high-sugar diet on dermatitis, our aim is to improve understanding of the influence of a high-sugar diet on ACD. We introduced a diet rich in sugar fifteen days before inducing contact dermatitis with oxazolone, in mice, and maintained it until the end of the experiment, which lasted three weeks in total. The dermatitis model increased cholesterol and triglycerides in the liver, and the combination of diet and dermatitis increased weight and worsened liver cholesterol measurements. Furthermore, the high-sugar diet increased the production of IL-6, IFN-γ and TNF-α in the skin, which may be involved in the increase in epithelial skin thickness observed in experimental ACD.

Statins in Cirrhosis: Hope or Hype?

In recent years, studies have demonstrated the benefits of statins in a range of chronic diseases separate from cardiovascular outcomes. Early studies in the context of chronic liver disease have suggested favorable effects of statins leading to slowed fibrosis progression, reduced portal pressures, decreased rates of hepatic decompensation, and improved survival. This has increased interest in the potential role that statins may have in the management of chronic liver disease and cirrhosis, though many questions remain unanswered, including concerns regarding the safety of higher dose statins in patients with advanced decompensated cirrhosis. In this review, we provide an update on the current literature addressing the use of statins in patients with cirrhosis and highlight areas in which additional studies are needed.

Engineered human hepatocyte organoids enable CRISPR-based target discovery and drug screening for steatosis

The lack of registered drugs for nonalcoholic fatty liver disease (NAFLD) is partly due to the paucity of human-relevant models for target discovery and compound screening. Here we use human fetal hepatocyte organoids to model the first stage of NAFLD, steatosis, representing three different triggers: free fatty acid loading, interindividual genetic variability (PNPLA3 I148M) and monogenic lipid disorders (APOB and MTTP mutations). Screening of drug candidates revealed compounds effective at resolving steatosis. Mechanistic evaluation of effective drugs uncovered repression of de novo lipogenesis as the convergent molecular pathway. We present FatTracer, a CRISPR screening platform to identify steatosis modulators and putative targets using APOB-/- and MTTP-/- organoids. From a screen targeting 35 genes implicated in lipid metabolism and/or NAFLD risk, FADS2 (fatty acid desaturase 2) emerged as an important determinant of hepatic steatosis. Enhancement of FADS2 expression increases polyunsaturated fatty acid abundancy which, in turn, reduces de novo lipogenesis. These organoid models facilitate study of steatosis etiology and drug targets.

Nonalcoholic fatty liver disease without overlapping metabolic-associated fatty liver disease and the risk of incident type 2 diabetes

BACKGROUND AND AIMS

Re-classifying NAFLD as metabolic-associated fatty liver (MAFLD) has been proposed. While some people fulfil criteria for NAFLD, they do not have MAFLD; and whether NAFLD-only subjects have increased the risk of type 2 diabetes remains unknown. We compared risk of incident T2D in individuals with: (a) NAFLD-only; and (b) MAFLD, to individuals without fatty liver, considering effect modification by sex.

METHODS

246 424 Koreans without diabetes or a secondary cause of ultrasound-diagnosed hepatic steatosis were studied. Subjects were stratified into: (a) NAFLD-only status and (b) NAFLD that overlapped with MAFLD (MAFLD). Cox proportional hazards models with incident T2D as the outcome were used to estimate hazard ratios (HRs) for: (a) and (b). Models were adjusted for time-dependent covariates, and effect modification by sex was analysed in subgroups.

RESULTS

A total of 5439 participants had NAFLD-only status and 56 839 met MAFLD criteria. During a median follow-up of 5.5 years, 8402 incident cases of T2D occurred. Multivariable-adjusted HRs (95% CI) for incident T2D comparing NAFLD-only and MAFLD to the reference (neither condition) were 2.39 (1.63-3.51) and 5.75 (5.17-6.36) (women), and 1.53 (1.25-1.88) and 2.60 (2.44-2.76) (men), respectively. The increased risk of T2D in the NAFLD-only group was higher in women than in men (p for interaction by sex <0.001) and consistently observed across all subgroups. Risk of T2D was increased in lean participants regardless of metabolic dysregulation (including prediabetes).

CONCLUSIONS

NAFLD-only participants without metabolic dysregulation and the criteria for MAFLD are at increased risk of developing T2D. This association was consistently stronger in women than in men.

Association between hemoglobin glycation index and non-alcoholic fatty liver disease in the patients with type 2 diabetes mellitus

AIMS/INTRODUCTION

The hemoglobin glycation index (HGI) represent the disparity between actual glycated hemoglobin measurements and predicted HbA1c. It serves as a proxy for the degree of non-enzymatic glycation of hemoglobin, which has been found to be positively correlated with diabetic comorbidities. In this study, we investigated the relationship between HGI and non-alcoholic fatty liver disease (NAFLD), along with other relevant biological markers in patients with diabetes.

MATERIALS AND METHODS

This cross-sectional study consisted of 3,191 adults diagnosed with type 2 diabetes mellitus. We calculated the predicted glycated hemoglobin levels based on fasting blood glucose levels. Multivariate binary logistic regression analysis was conducted to examine the correlation between the HGI and NAFLD. Hepatic steatosis was diagnosed using ultrasonography.

RESULTS

Among all participants, 1,784 (55.91%) were diagnosed with NAFLD. Participants with confirmed NAFLD showed elevated body mass index, diastolic blood pressure, liver enzyme, total cholesterol, triglyceride, low-density lipoprotein and uric acid levels compared with those without NAFLD. In the unadjusted model, participants in the last tertile of HGI were 1.40-fold more likely to develop NAFLD than those in the first tertile (95% confidence interval 1.18-1.66; P < 0.001). In the fully adjusted model, those in the last tertile of HGI had a 39% increased risk of liver steatosis compared with confidence interval in the first tertile of HGI (95% confidence interval 1.12-1.74; P < 0.001).

CONCLUSIONS

A higher HGI suggests an elevated risk of developing NAFLD in patients with type 2 diabetes.

Association between total body muscle percentage and prevalence of non-alcoholic fatty liver disease in Korean adults findings from an 18-year follow-up: a prospective cohort study

BACKGROUND

This study aimed to elucidate the association between total lean muscle mass and the incidence of non-alcoholic fatty liver disease (NAFLD) in the adult Korean population.

METHODS

Utilizing data derived from the 18-year prospective cohort of the Korean Genome and Epidemiology Study, NAFLD was diagnosed via the hepatic steatosis index with an established cutoff value of 36. Lean muscle mass was assessed via bioelectrical impedance analysis and subsequently divided into tertiles. A generalized mixed model with a logit link was employed for repeated measures data analysis, accounting for potential confounders.

RESULTS

Analysis encompassed 7,794 participants yielding 49,177 measurements. The findings revealed a markedly increased incidence of NAFLD in the lower tertiles of muscle mass, specifically, tertile 1 (odds ratio [OR], 20.65; 95% confidence interval [CI], 9.66-44.11) and tertile 2 (OR, 4.57; 95% CI, 2.11-9.91), in comparison to tertile 3. Age-dependent decreases in the OR were observed within the tertile 1 group, with ORs of 10.12 at age of 40 years and 4.96 at age of 80 years. Moreover, each 1%-point increment in total muscle mass corresponded with an estimated OR of 0.87 (95% CI, 0.82-0.93) for NAFLD resolution.

CONCLUSIONS

The study demonstrates a significant association between total muscle mass and NAFLD prevalence among Korean adults. Given the potential endocrine role of muscle mass in NAFLD pathogenesis, interventions aimed at enhancing muscle mass might serve as an effective public health strategy for mitigating NAFLD prevalence.

The impact of concomitant hepatitis C virus infection on liver and cardiovascular risks in patients with metabolic-associated fatty liver disease

BACKGROUND

Chronic hepatitis C virus (HCV)-infected patients with hepatic steatosis are excluded from the diagnosis of nonalcoholic fatty liver disease (NAFLD). The new name and diagnostic criteria of metabolic-associated fatty liver disease (MAFLD) were proposed in 2020 to replace the original term NAFLD. The clinical outcome of MAFLD patients with concomitant chronic HCV infection requires further investigation.

METHODS

The participants from Taiwan bio-bank cohort were included. MAFLD is defined as the presence of fatty liver, plus any of the following three conditions: overweight/obesity, type 2 diabetes, or metabolic dysfunction. The patients with positive anti-HCV were considered chronic HCV infections. The severity of liver fibrosis was determined using the fibrosis-4 index and NAFLD fibrosis score (NFS). The risk of cardiovascular disease (CVD) was assessed using intima-media thickness (IMT) or plaques of carotid duplex ultrasound.

RESULTS

A total of 18 907 participants (age 55.79 ± 10.42; males 31.9%) were included for final analysis. The prevalence of MAFLD and chronic HCV infections were 39.2% and 2.6%, respectively. According to the status of MAFLD and chronic HCV infection, they were distributed to four groups: 'dual etiology group', 'MAFLD alone', 'HCV alone', and healthy controls. Compared with the 'MAFLD alone' group, the 'dual etiology' group had a lower frequency of the male sex, reduced levels of serum triglyceride, total cholesterol, and LDL; but overall older age, a higher percentage of hypertension history. In addition, they had higher levels of serum aspartate aminotransferase, fibrosis-4 index, and NFS; but no difference in levels of alanine aminotransferase, gamma-glutamyl transferase, fatty liver index, IMT, and the percentage of carotid plaques. Using binary logistic regression, chronic HCV infection was associated with more severe liver fibrosis, but not with carotid plaques in MAFLD patients.

CONCLUSION

MAFLD patients with concomitant HCV infection, a specific phenotype of MAFLD may include a higher risk of advanced liver fibrosis, but a similar risk of atherosclerotic cardiovascular disease compared to those without.

Swimming exercise ameliorates insulin resistance and nonalcoholic fatty liver by negatively regulating PPARγ transcriptional network in mice fed high fat diet

BACKGROUND

Recent findings elucidated hepatic PPARγ functions as a steatogenic-inducer gene that activates de novo lipogenesis, and is involved in regulation of glucose homeostasis, lipid accumulation, and inflammation response. This study delved into a comprehensive analysis of how PPARγ signaling affects the exercise-induced improvement of insulin resistance (IR) and non-alcoholic fatty liver disease (NAFLD), along with its underlying mechanism.

METHODS

Chronic and acute swimming exercise intervention were conducted in each group mice. IR status was assessed by GTT and ITT assays. Serum inflammatory cytokines were detected by Elisa assays. PPARγ and its target genes expression were detected by qPCR assay. Relative protein levels were quantified via Western blotting. ChIP-qPCR assays were used to detect the enrichment of PPARγ on its target genes promoter.

RESULTS

Through an exploration of a high-fat diet (HFD)-induced IR and NAFLD model, both chronic and acute swimming exercise training led to significant reductions in body weight and visceral fat mass, as well as hepatic lipid accumulation. The exercise interventions also demonstrated a significant amelioration in IR and the inflammatory response. Meanwhile, swimming exercise significantly inhibited PPARγ and its target genes expression induced by HFD, containing CD36, SCD1 and PLIN2. Furthermore, swimming exercise presented significant modulation on regulatory factors of PPARγ expression and transcriptional activity.

CONCLUSION

The findings suggest that swimming exercise can improve lipid metabolism in IR and NAFLD, possibly through PPARγ signaling in the liver of mice.

Association of fat-to-muscle ratio with non-alcoholic fatty liver disease: a single-centre retrospective study

OBJECTIVES

Sarcopenia is a known risk factor for non-alcoholic fatty liver disease (NAFLD). Studies evaluating the association between the fat-to-muscle ratio (FMR) and NAFLD are limited. Therefore, the aim of our study was to investigate the association between FMR and NAFLD.

DESIGN

A retrospective study was conducted on individuals who underwent health examination at Wuhan Union Hospital between January 2020 and November 2021. Clinical data were collected from electronic medical records.

SETTING

Wuhan Union Hospital, Wuhan, China.

PARTICIPANTS

1592 participants aged ≥40 years who underwent body composition analysis and liver ultrasonography were retrospectively reviewed.

OUTCOME MEASURES

Liver ultrasonography was used to assess liver steatosis, and the fibrosis-4 index was used to calculate the risk scores for liver fibrosis. The 10-year atherosclerotic cardiovascular disease (ASCVD) risk prediction model was used to calculate ASCVD risk scores.

RESULTS

The FMR was significantly higher in individuals with NAFLD than in those without NAFLD (p<0.001). The prevalence of NAFLD gradually increased from FMR tertile 1 (reference) to tertile 2 (OR=1.49, 95% CI 1.13 to 1.97) and tertile 3 (OR=2.85, 95% CI 2.08 to 3.90). In addition, patients with NAFLD in FMR tertile 3 had a significantly higher risk of liver fibrosis (OR=4.48, 95% CI 2.12 to 9.50) and ASCVD (OR=4.63, 95% CI 2.62 to 8.19) than those in FMR tertile 1 after adjustment for multiple confounders.

CONCLUSION

In this study, we found a significant association between FMR and NAFLD. A higher FMR indicates a higher risk of NAFLD in the study population and a higher risk of liver fibrosis and ASCVD in NAFLD patients.

Metabolic syndrome and transaminases: systematic review and meta-analysis

BACKGROUND

Metabolic syndrome (MetS) is a group of metabolic abnormalities characterised by hypertension, central obesity, dyslipidaemia and dysregulation of blood glucose, associated with the risk of diabetes, cardiovascular disease and overall mortality. The presence of elevated liver enzymes may precede the development of MetS, with alterations of the liver being observed that are directly related to metabolic problems. The study aims to provide the best evidence on the association between liver enzymes (ALT, AST, GGT) and MetS by determining the effect size of these biomarkers.

METHODS

A systematic review and meta-analysis of studies indexed in PubMed and Scopus databases were performed. Study quality was assessed using the STROBE tool. The Grade Pro tool was used to evaluate the evidence, and the quantitative synthesis was performed using RevMan (Cochrane Collaboration).

RESULTS

Seventeen articles comparing liver enzyme concentrations between 76,686 with MetS (MetS+) and 201,855 without MetS (MetS-) subjects were included. The concentration of ALT, AST and GGT in the MetS + subjects was significantly higher than in the control group 7.13 IU/L (CI95% 5.73-8.54; p < 0.00001; I2 = 96%), 2.68 IU/L (CI95% 1.82-3.54; p < 0.00001; I2 = 96%) and 11.20 IU/L (CI95% 7.11-15.29; p < 0.00001; I2 = 96%), respectively.

CONCLUSIONS

The evaluation of the relationship of liver enzymes in the pathophysiological process of MetS could lead to new insights into early diagnosis.

Liver Fat Scores for Noninvasive Diagnosis and Monitoring of Nonalcoholic Fatty Liver Disease in Epidemiological and Clinical Studies

Nonalcoholic fatty liver disease (NAFLD) is strongly associated with the metabolic syndrome and type 2 diabetes and independently contributes to long-term complications. Being often asymptomatic but reversible, it would require population-wide screening, but direct diagnostics are either too invasive (liver biopsy), costly (MRI) or depending on the examiner's expertise (ultrasonography). Hepatosteatosis is usually accommodated by features of the metabolic syndrome (e.g. obesity, disturbances in triglyceride and glucose metabolism), and signs of hepatocellular damage, all of which are reflected by biomarkers, which poorly predict NAFLD as single item, but provide a cheap diagnostic alternative when integrated into composite liver fat indices. Fatty liver index, NAFLD LFS, and hepatic steatosis index are common and accurate indices for NAFLD prediction, but show limited accuracy for liver fat quantification. Other indices are rarely used. Hepatic fibrosis scores are commonly used in clinical practice, but their mandatory reflection of fibrotic reorganization, hepatic injury or systemic sequelae reduces sensitivity for the diagnosis of simple steatosis. Diet-induced liver fat changes are poorly reflected by liver fat indices, depending on the intervention and its specific impact of weight loss on NAFLD. This limited validity in longitudinal settings stimulates research for new equations. Adipokines, hepatokines, markers of cellular integrity, genetic variants but also simple and inexpensive routine parameters might be potential components. Currently, liver fat indices lack precision for NAFLD prediction or monitoring in individual patients, but in large cohorts they may substitute nonexistent imaging data and serve as a compound biomarker of metabolic syndrome and its cardiometabolic sequelae.

Community-centered Disease Severity Assessment of Metabolic Dysfunction-associated Fatty Liver Disease

Background and Aims

Disease severity across the different diagnostic categories of metabolic dysfunction-associated fatty liver disease (MAFLD) remains elusive. This study assessed the fibrosis stages and features of MAFLD between different items. We also aimed to investigate the associations between advanced fibrosis and risk factors.

Methods

This multicenter cross-sectional study enrolled adults participating in liver disease screening in the community. Patients were stratified following MAFLD diagnostic criteria, to group A (395 patients) for type 2 diabetes, group B (1,818 patients) for body mass index (BMI)>23 kg/m2, and group C (44 patients) for BMI≤23 kg/m2 with at least two metabolic factors. Advanced fibrosis was defined as a fibrosis-4 index>2.67.

Results

Between 2009 and 2020, 1,948 MAFLD patients were recruited, including 478 with concomitant liver diseases. Advanced fibrosis was observed in 125 patients. A significantly larger proportion of patients in group C (25.0%) than in group A (7.6%) and group B (5.8%) had advanced fibrosis (p<0.01). Logistic regression analysis found that hepatitis B virus (HBV)/hepatitis C virus (HCV) coinfection (odds ratio [OR]: 12.14, 95% confidence interval [CI]: 4.04-36.52; p<0.01), HCV infection (OR: 7.87, 95% CI: 4.78-12.97; p<0.01), group C (OR: 6.00, 95% CI: 2.53-14.22; p<0.01), and TC/LDL-C (OR: 1.21, 95% CI: 1.06-1.38; p<0.01) were significant predictors of advanced fibrosis.

Conclusions

A higher proportion of lean MAFLD patients with metabolic abnormalities had advanced fibrosis. HCV infection was significantly associated with advanced fibrosis.

Clinical Classification of Obesity and Implications for Metabolic Dysfunction-Associated Fatty Liver Disease and Treatment

Obesity,and metabolic dysfunction-associated fatty liver disease (MAFLD) have reached epidemic proportions globally. Obesity and MAFLD frequently coexist and act synergistically to increase the risk of adverse clinical outcomes (both hepatic and extrahepatic). Type 2 diabetes mellitus (T2DM) is the most important risk factor for rapid progression of steatohepatitis and advanced fibrosis. Conversely, the later stages of MAFLD are associated with an increased risk of T2DM incident. According to the proposed criteria, MAFLD is diagnosed in patients with liver steatosis and in at least one in three: overweight or obese, T2DM, or signs of metabolic dysregulation if they are of normal weight. However, the clinical classification and correlation between obesity and MAFLD is more complex than expected. In addition, treatment for obesity and MAFLD are associated with a reduced risk of T2DM, suggesting that liver-based treatments could reduce the risk of developing T2DM. This review describes the clinical classification of obesity and MAFLD, discusses the clinical features of various types of obesity and MAFLD, emphasizes the role of visceral obesity and insulin resistance (IR) in the development of MAFLD,and summarizes the existing treatments for obesity and MAFLD that reduce the risk of developing T2DM.

Gene Variants Implicated in Steatotic Liver Disease: Opportunities for Diagnostics and Therapeutics

Non-alcoholic fatty liver disease (NAFLD) describes a steatotic (or fatty) liver occurring as a consequence of a combination of metabolic, environmental, and genetic factors, in the absence of significant alcohol consumption and other liver diseases. NAFLD is a spectrum of conditions. Steatosis in the absence of inflammation is relatively benign, but the disease can progress into more severe forms like non-alcoholic steatohepatitis (NASH), liver cirrhosis, and hepatocellular carcinoma. NAFLD onset and progression are complex, as it is affected by many risk factors. The interaction between genetic predisposition and other factors partially explains the large variability of NAFLD phenotype and natural history. Numerous genes and variants have been identified through large-scale genome-wide association studies (GWAS) that are associated with NAFLD and one or more subtypes of the disease. Among them, the largest effect size and most consistent association have been patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily member 2 (TM6SF2), and membrane-bound O-acyltransferase domain containing 7 (MBOAT7) genes. Extensive in vitro and in vivo studies have been conducted on these variants to validate these associations. The focus of this review is to highlight the genetics underpinning the molecular mechanisms driving the onset and progression of NAFLD and how they could potentially be used to improve genetic-based diagnostic testing of the disease and develop personalized, targeted therapeutics.

Dihydroartemisinin ameliorates the liver steatosis in metabolic associated fatty liver disease mice by attenuating the inflammation and oxidative stress and promoting autophagy

PURPOSE

To explore the effect and potential mechanism of dihydroartemisinin (DHA) on metabolism-related fatty liver disease.

METHODS

A metabolic associated fatty liver disease (MAFLD) mice model was induced with continuous supplies of high-fat diet. DHA was intraperitoneally injected into mice. The weight of mice was monitored. The concentrations of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) in serum were detected by an automatic biochemical analyzer. The liver tissues were stained by hematoxylin and eosin and oil red O. The level of inflammation, oxidative stress, and autophagy was assessed by reverse transcription polymerase chain reaction, biochemical examination, Western blot and transmission electron microscope assays.

RESULTS

DHA treatment reduced theMAFLD-enhanced the level of weight gain, the concentrations of TC, TG, LDL and malonaldehyde, while increasedthe MAFLD-decreased the concentrations of HDL and superoxide dismutase. DHA ameliorated the MAFLD-aggravated pathological changes and the number of lipid droplets. Low dose of DHA declined the MAFLD-induced the enhancement of the expression of inflammatory factor. DHA treatment increased the MAFLD-enhanced the level of autophagy related protein, while decreased the MAFLD-reduced the protein level of p62. The increased level of autophagy was confirmed by transmission electron microscope.

CONCLUSIONS

DHA can improve liver steatosis in MAFLD mice by inhibiting inflammation and oxidative stress and promoting autophagy.

Association of sex hormones and sex hormone-binding globulin with liver fat in men and women: an observational and Mendelian randomization study

Background

Sex hormones and sex hormone-binding globulin (SHBG) may play a role in fatty liver development. We sought to examine the association of various endogenous sex hormones, including testosterone (T), and SHBG with liver fat using complementary observational and Mendelian randomization (MR) analyses.

Methods

The observational analysis included a total of 2,239 participants (mean age 60 years; 35% postmenopausal women) from the population-based KORA study (average follow-up time: 6.5 years). We conducted linear regression analysis to investigate the sex-specific associations of sex hormones and SHBG with liver fat, estimated by fatty liver index (FLI). For MR analyses, we selected genetic variants associated with sex hormones and SHBG and extracted their associations with magnetic resonance imaging measured liver fat from the largest up to date European genome-wide associations studies.

Results

In the observational analysis, T, dihydrotestosterone (DHT), progesterone and 17α-hydroxyprogesterone (17-OHP) were inversely associated with FLI in men, with beta estimates ranging from -4.23 to -2.30 [p-value <0.001 to 0.003]. Whereas in women, a positive association of free T with FLI (β = 4.17, 95%CI: 1.35, 6.98) was observed. SHBG was inversely associated with FLI across sexes [men: -3.45 (-5.13, -1.78); women: -9.23 (-12.19, -6.28)]. No causal association was found between genetically determined sex hormones and liver fat, but higher genetically determined SHBG was associated with lower liver fat in women (β = -0.36, 95% CI: -0.61, -0.12).

Conclusion

Our results provide suggestive evidence for a causal association between SHBG and liver fat in women, implicating the protective role of SHBG against liver fat accumulation.

The Surreptitious Burden of Nonalcoholic Fatty Liver Disease in the Elderly in the Asia-Pacific Region: An Insight from the Global Burden of Disease Study 2019

Nonalcoholic fatty liver disease (NAFLD) represents a significant health threat worldwide. The aging population and a rise in metabolic syndrome in Asia might influence the epidemiology of NAFLD among the elderly. However, there is a lack of understanding of the burden and recommendations for NAFLD in this group. Our study sought to investigate the trends in the NAFLD burden among the elderly in the Asia-Pacific region. We employed data from the Global Burden of Disease 2019 study for an in-depth analysis of the prevalence and disability-adjusted life years (DALYs) along with age-standardized rate (ASR) associated with NAFLD in elderly populations (age 65-89 years) across the Asia-Pacific region, including the Southeast Asia (SEA) and Western Pacific (WP) regions, from 2010 to 2019. This study also examined the trends and disparities in NAFLD burden across different nations and sexes. In 2019, there were over 120 million cases of NAFLD in the elderly in the Asia-Pacific region. The ASR of prevalence was higher in SEA compared to WP (36,995.37 vs. 32,821.78 per 100,000). ASR of prevalence increased with annual percentage change (APC) +0.95% in the WP while it increased by +0.87% in SEA. During the study period, the ASR of DALYs decreased in SEA (APC -0.41%) but remained stable in the WP region. The burden of NAFLD in the elderly population in Asia-Pacific has increased, underscoring the timely intervention to tackle this high and rising burden.

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

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

Serum metabolomic profiling unveils distinct sex-related metabolic patterns in NAFLD

Objective

Obesity poses an increased risk for the onset of Nonalcoholic fatty liver disease (NAFLD). The influence of other factors, such as sex in the incidence and severity of this liver disease has not yet been fully elucidated. Thus, we aimed to identify the NAFLD serum metabolic signatures associated with sex in normal, overweight and obese patients and to associate the metabolite fluctuations across the increasing liver steatosis stages.

Methods and results

Using nuclear magnetic resonance (NMR) serum samples of 210 NAFLD cases and control individuals diagnosed with liver U/S, our untargeted metabolomics enquiry provided a sex distinct metabolic bouquet. Increased levels of alanine, histidine and tyrosine are associated with severity of NAFLD in both men and women. Moreover, higher serum concentrations of valine, aspartic acid and mannose were positively associated with the progression of NAFLD among the male subjects, while a negative association was observed with the levels of creatine, phosphorylcholine and acetic acid. On the other hand, glucose was positively associated with the progression of NAFLD among the female subjects, while levels of threonine were negatively related. Fluctuations in ketone bodies acetoacetate and acetone were also observed among the female subjects probing a significant reduction in the circulatory levels of the former in NAFLD cases. A complex glycine response to hepatic steatosis of the female subjects deserves further investigation.

Conclusion

Results of this study aspire to address the paucity of data on sex differences regarding NAFLD pathogenesis. Targeted circulatory metabolome measurements could be used as diagnostic markers for the distinct stages of NAFLD in each sex and eventually aid in the development of novel sex-related therapeutic options.

Metabolic dysfunction-associated fatty liver disease is an early predictor for testosterone deficiency in aging men without metabolic syndrome

Background and aims

Metabolic dysfunction-associated fatty liver disease (MAFLD) has emerged as a valuable marker for identifying individuals at increased risk of metabolic dysfunction, liver-related complications, and cardiovascular disease. However, the association between MAFLD and testosterone deficiency (TD) in aging men remains poorly understood. This study aimed to investigate the association between MAFLD and the risk of TD in aging Taiwanese men, with a specific focus on those without metabolic syndrome (MetS).

Methods

A free health screening program was conducted for Taiwanese men aged over 40 years in Kaohsiung, Taiwan. Participants underwent physical examinations, completed questionnaires regarding demographics, medical history, and clinical symptoms of TD, and provided 20-mL whole blood samples for biochemical, adipocytokine, and hormonal evaluations. Fatty liver index was used to evaluate the risk of fatty liver. Diagnostic criteria for MAFLD included fatty liver along with overweight/obesity, type 2 diabetes, or evidence of metabolic dysregulation.

Results

A total of 631 men (mean age: 54.4 ± 8.4 years) were enrolled. The prevalence rates of TD and MetS were significantly higher in men with MAFLD compared to those without (both p < 0.001). Additionally, the presence of MAFLD showed a significant correlation with adipocytokines associated with insulin resistance, such as adiponectin, leptin, and retinol-binding protein-4 (RBP-4) levels (all p < 0.001). Among men without MetS, those with MAFLD had a 3.89- and 4.74-fold higher risk of total testosterone < 300 ng/dL and TD, respectively, after adjusting for potential covariates.

Conclusion

MAFLD is associated with an elevated risk of TD in aging Taiwanese men, particularly in the absence of MetS. This finding suggests that MAFLD could serve as an early predictor of TD, facilitating the identification of high-risk individuals and enabling timely interventions. Further research is needed to validate these findings and explore the underlying mechanisms linking MAFLD, TD, and MetS in diverse populations.

Clinical impact of hepatic steatosis on chronic hepatitis B patients in Asia: A systematic review and meta-analysis

Chronic hepatitis B (CHB) and hepatic steatosis (HS) are two prevalent chronic liver diseases in Asia. The incidence of CHB combined with HS is increasing due to the rising obesity rates. However, the impact of HS on CHB remains a topic of debate. Hereby, this meta-analysis aims to examine the effect of HS on Asian patients with CHB. Searches were conducted on four databases to identify articles published from 2005 to 2023. The random-effects or fixed-effects model was used to calculate pooled odds ratios (ORs), weighted mean difference (WMD), and confidence intervals (CIs) for the included articles. Of the 15,959 records screened, 88 studies were included in the analysis of HS prevalence in Asian CHB patients with a prevalence of 36.5% (95% CI: 33.7%-39.3%). In addition, age, sex, body mass index (BMI), waist circumference (WC), alanine aminotransferase (ALT) and combined metabolic diseases have varying degrees of impact on HS in CHB patients. Furthermore, the coexistence of HS was negatively associated with the response to antiviral therapy, including hepatitis B surface antigen (HBeAg) seroconversion (OR = 0.69, 95% CI: 0.53-0.89) and ALT normalization (OR = 0.75, 95% CI: 0.61-0.92) in CHB patients after 48 weeks of treatment. Regarding disease prognosis, HS was not significantly associated with fibrosis or cirrhosis in CHB patients, while an inverse association was observed between HS and hepatocellular carcinoma (HCC) (OR = 2.93, 95% CI: 1.23-6.99). This implies that the coexistence of HS in CHB patients may exacerbate the progression of HCC, which needs to be verified by further studies.

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.

Sensitivity and specificity of three diabetes diagnostic criteria in people with non-alcoholic fatty liver disease (NAFLD) and otherwise healthy people: Analysis of NHANES III

AIMS

Establishing whether fasting plasma glucose (FPG), postprandial glucose (PPG), and HbA1c have the same diagnostic accuracy in NAFLD versus otherwise healthy people could inform T2DM screening recommendations for those with NAFLD.

METHODS

Cross-sectional analysis of the Third National Health and Nutrition Examination Survey (NHANES III) 1989-1994. T2DM was defined as PPG ≥ 200 mg/dL, FPG ≥ 126 mg/dL, or HbA1c ≥ 6.5 %. We estimated sensitivity and specificity between the six pairwise combinations between the three T2DM definitions in people with and without NAFLD. With Poisson regressions, we investigated if people with NAFLD were more likely to have T2DM with two diagnostic criteria yet not with the third one.

RESULTS

There were 3652 people with mean age 55.6 years and 49.4 % were men; 673 (18.4 %) people had NAFLD. Compared to NAFLD-free individuals, those with NAFLD had lower specificity in all pairwise comparisons except when PPG was the reference vs HbA1c [98.28 % (95 % CI: 97.73 %-98.72 %) in people without NAFLD vs 96.15 % (95 % CI: 94.28 %-97.54 %)]. The sensitivity of FPG was slightly superior to PPG and HbA1c in people without NAFLD; for example, 64.62 % (95 % CI: 55.75 %-72.80 %) for FPG vs 56.58 % (95 % CI: 44.71 %-67.92 %) for HbA1c. People with NAFLD were more likely to be diagnosed with FPG and PPG yet not with HbA1c (PR=2.15; p = 0.020).

CONCLUSIONS

While these T2DM diagnostic criteria may capture different patients both in people with and without NAFLD, in the NAFLD population FPG appears to have the best sensitivity and there were no differences between PPG and HbA1c in terms of specificity.

Protective effects of statins on the incidence of NAFLD-related decompensated cirrhosis in T2DM

BACKGROUND AND AIMS

Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome and poses a significant threat to patients with type 2 diabetes mellitus (T2DM) and metabolic dysregulation. Statins exert anti-inflammatory, antioxidative and antithrombotic effects that target mechanisms underlying NAFLD. However, the protective effects of the different doses, intensities and types of statins on the incidence of NAFLD-related decompensated liver cirrhosis (DLC) in patients with T2DM remain unclear.

METHODS

This study used the data of patients with T2DM who were non-HBV and non-HCV carriers from a national population database to examine the protective effects of statin use on DLC incidence through propensity score matching. The incidence rate (IR) and incidence rate ratios (IRRs) of DLC in patients with T2DM with or without statin use were calculated.

RESULTS

A higher cumulative dose and specific types of statins, namely rosuvastatin, pravastatin, atorvastatin, simvastatin and fluvastatin, reduced the risk of DLC in patients with T2DM. Statin use was associated with a significant reduction in the risk of DLC (HR: .65, 95% CI: .61-.70). The optimal daily intensity of statin use with the lowest risk of DLC was .88 defined daily dose (DDD).

CONCLUSIONS

The results revealed the protective effects of specific types of statins on DLC risk in patients with T2DM and indicated a dose-response relationship. Additional studies are warranted to understand the specific mechanisms of action of different types of statins and their effect on DLC risk in patients with T2DM.

Outcomes and Risk Factors for Complications in Cataract Patients with Hepatitis C Virus Infection

PURPOSE

To describe outcomes of patients with hepatitis C virus (HCV) seropositivity undergoing cataract surgery, as well as investigate risk factors for surgical complications.

METHODS

This is a retrospective cohort study of all consecutive patients who underwent cataract surgery at a tertiary care hospital in the United States between 2014 and 2019. The exposure of interest was HCV seropositivity and outcomes included surgical complications and associated risk factors, visual acuity, and post-operative complications.

RESULTS

A total of 11,276 eyes of 6,858 patients were included in the study, of which 122 patients (1.78%) and 210 eyes (1.86%) were HCV positive. Average age at surgery was 63.4 (8.4) years for HCV positive patients and 69.1 (10.6) years for HCV negative patients. Patients with HCV were more likely to suffer a complication during cataract surgery, 2.9% versus 1.2% (OR 2.27, 95% CI 1.03 to 5.01, p = .0415). Postoperative best corrected visual acuity was excellent: median and range 0.00 (-0.13, 3.00) logMAR for HCV positive eyes versus 0.00 (-0.30, 3.00) logMAR for HCV negative eyes. Among HCV positive patients, elevated alanine transaminase (>52 U/L) was associated with a higher intraoperative complication rate (10.0% vs 1.8%, OR 5.53, 95% CI 1.05 to 29.2, p = .044).

CONCLUSION

While patients with HCV are more likely to have complications during cataract surgery, final best corrected visual acuity was excellent regardless of HCV status. Patients with HCV are more likely to undergo cataract surgery at a younger age, and those with elevated alanine transaminase are at highest risk for complications.

Long-term exposure to air pollution and prevalent nonalcoholic fatty liver disease

Background

Nonalcoholic fatty liver disease (NAFLD) is a disease characterized by lipid accumulation within hepatocytes, ranging from simple steatosis to steatohepatitis, in the absence of secondary causes of hepatic fat accumulation. Although air pollution (AP) has been associated with several conditions related to NAFLD (e.g., metabolic syndrome, type 2 diabetes mellitus), few studies have explored an association between AP and NAFLD. The aim of the study was to investigate whether exposure to AP is associated with NAFLD prevalence.

Methods

We used baseline cross-sectional data (2000-2003) of the Heinz-Nixdorf-Recall cohort study in Germany (baseline n = 4,814), a prospective population-based cohort study in the urbanized Ruhr Area. Mean annual exposure to size-fractioned particulate matter (PM10, PM2.5, PMcoarse, and PM2.5abs), nitrogen dioxide, and particle number was assessed using two different exposure models: a chemistry transport dispersion model, which captures urban background AP exposure on a 1 km2 grid at participant's residential addresses, and a land use regression model, which captures point-specific AP exposure at participant's residential addresses. NAFLD was assessed with the fatty liver index (n = 4,065), with NAFLD defined as fatty liver index ≥60. We estimated ORs of NAFLD per interquartile range of exposure using logistic regression, adjusted for socio-demographic and lifestyle variables.

Results

We observed a NAFLD prevalence of 31.7% (n = 1,288). All air pollutants were positively associated with NAFLD prevalence, with an OR per interquartile range for PM2.5 of 1.11 (95% confidence interval [CI] = 1.00, 1.24) using chemistry transport model, and 1.06 (95% CI = 0.94, 1.19) using the land use regression model, respectively.

Conclusion

There was a positive association between long-term AP exposure and NAFLD.

Altered Lipid Moieties and Carbonyls in a Wistar Rat Dietary Model of Subclinical Fatty Liver: Potential Sex-Specific Biomarkers of Early Fatty Liver Disease?

Non-alcoholic fatty liver disease (NAFLD) is a condition in which excess fat builds up in the liver. To date, there is a lack of knowledge about the subtype of lipid structures affected in the early stages of NAFLD. The aim of this study was to analyze serum and liver lipid moieties, specifically unsaturations and carbonyls, by nuclear magnetic resonance (NMR) in a subclinical Wistar rat model of NAFLD for detecting early alterations and potential sex dimorphisms. Twelve weeks of a high-fat diet (HFD) induced fat accumulation in the liver to a similar extent in male and female Wistar rats. In addition to total liver fat accumulation, Wistar rats showed a shift in lipid subtype composition. HFD rats displayed increased lipid carbonyls in both liver and serum, and decreased in unsaturated fatty acids (UFAs) and polyunsaturated fatty acids (PUFAs), with a much stronger effect in male than female animals. Our results revealed that the change in fat was not only quantitative but also qualitative, with dramatic shifts in relevant lipid structures. Finally, we compared the results found in Wistar rats with an analysis in a human patient cohort of extreme obesity. For the first time to our knowledge, lipid carbonyl levels and lipoproteins profiles were analyzed in the context of subclinical NAFLD. The association found between lipid carbonyls and alanine aminotransferase (ALT) in a human cohort of extremely obese individuals further supports the potential role of lipid moieties as biomarkers of early NAFLD.

Gender Differences in Insulin Resistance: New Knowledge and Perspectives

Insulin resistance is the main mechanism in a whole series of pathological conditions, which are not only of metabolic interest but also of a systemic type. This phenomenon means that the body's cells become less sensitive to the hormone insulin, leading to higher levels of insulin in the blood. Insulin resistance is a phenomenon that can be found in both men and women and in particular, in the latter, it is found mainly after menopause. Premenopause, hormonal fluctuations during the menstrual cycle, and the presence of estrogen can affect insulin sensitivity. Androgens, such as testosterone, are typically higher in men and can contribute to insulin resistance. In both sexes, different human body types affect the distribution and location of body fat, also influencing the development of diabetes and cardiovascular disease. Insulin resistance is also associated with some neurological and neurogenerative disorders, polycystic ovary syndrome, atherosclerosis, and some of the main neoplastic pathologies. A healthy lifestyle, including regular physical activity, a balanced diet, and self-maintenance, can help to prevent the onset of insulin resistance, regardless of gender, although the different habits between men and women greatly affect the implementation of preventative guidelines that help in fighting the manifestations of this metabolic disorder. This review may help to shed light on gender differences in metabolic diseases by placing a necessary focus on personalized medical management and by inspiring differentiated therapeutic approaches.

Understanding the Relationship between Nonalcoholic Fatty Liver Disease and Thyroid Disease

The prevalence of hypothyroidism in patients with nonalcoholic fatty liver disease (NAFLD) is high (22.4%). Thyroid hormones (THs) regulate many metabolic activities in the liver by promoting the export and oxidation of lipids, as well as de novo lipogenesis. They also control hepatic insulin sensitivity and suppress hepatic gluconeogenesis. Because of its importance in lipid and carbohydrate metabolism, the involvement of thyroid dysfunction in the pathogenesis of NAFLD seems plausible. The mechanisms implicated in this relationship include high thyroid-stimulating hormone (TSH) levels, low TH levels, and chronic inflammation. The activity of the TH receptor (THR)-β in response to THs is essential in the pathogenesis of hypothyroidism-induced NAFLD. Therefore, an orally active selective liver THR-β agonist, Resmetirom (MGL-3196), was developed, and has been shown to reduce liver fat content, and as a secondary end point, to improve nonalcoholic steatohepatitis. The treatment of NAFLD with THR-β agonists seems quite promising, and other agonists are currently under development and investigation. This review aims to shine a light on the pathophysiological and epidemiological evidence regarding this relationship and the effect that treatment with THs and selective liver THR-β agonists have on hepatic lipid metabolism.