Nonalcoholic fatty liver disease (NAFLD) from pathogenesis to treatment concepts in humans

Similar weight loss with semaglutide regardless of diabetes and cardiometabolic risk parameters in individuals with metabolic dysfunction-associated steatotic liver disease: Post hoc analysis of three randomised controlled trials

AIMS

Weight loss mediated by glucagon-like peptide-1 (GLP-1) analogues is lower in patients with type 2 diabetes versus those without. Type 2 diabetes and obesity are risk factors for metabolic dysfunction-associated steatotic liver disease (MASLD) and associated steatohepatitis (MASH). We evaluated weight changes in adults with MASLD/MASH with or without type 2 diabetes receiving the GLP-1 analogue semaglutide.

MATERIALS AND METHODS

This was a post hoc analysis of data from three 48-72-week randomised trials investigating the effect of semaglutide versus placebo in adults with MASLD (NCT03357380) or biopsy-confirmed MASH (NCT02970942 and NCT03987451). Pooled data for semaglutide (0.4 mg once daily and 2.4 mg once weekly [n = 163]) and placebo (n = 137) were analysed at 1 year. Weight changes were analysed by type 2 diabetes status (type 2 diabetes [n = 209], pre-type 2 diabetes [n = 51] and no diabetes [n = 40]) and by other cardiometabolic risk parameters using analysis of covariance and Spearman's rank correlations.

RESULTS

The overall mean weight change was -11.1 kg (-11.7%) and -0.7 kg (-0.6%) with semaglutide and placebo, respectively. While numerically higher for people without type 2 diabetes, estimated treatment differences with semaglutide versus placebo were similar overall for people with type 2 diabetes (-10.2 kg; -10.8%), pre-type 2 diabetes (-9.8 kg; -10.2%) and no diabetes (-11.6 kg; -13.1%). Differences between groups were not statistically significant (p > 0.50 for all). Baseline fasting plasma glucose, glycated haemoglobin, insulin levels, insulin resistance and lipids did not correlate with weight change.

CONCLUSIONS

People with MASLD/MASH had similar semaglutide-mediated weight loss regardless of type 2 diabetes status and other cardiometabolic risk parameters.

Inhibited peroxidase activity of peroxiredoxin 1 by palmitic acid exacerbates nonalcoholic steatohepatitis in male mice

Reactive oxygen species exacerbate nonalcoholic steatohepatitis (NASH) by oxidizing macromolecules; yet how they promote NASH remains poorly understood. Here, we show that peroxidase activity of global hepatic peroxiredoxin (PRDX) is significantly decreased in NASH, and palmitic acid (PA) binds to PRDX1 and inhibits its peroxidase activity. Using three genetic models, we demonstrate that hepatic PRDX1 protects against NASH in male mice. Mechanistically, PRDX1 suppresses STAT signaling and protects mitochondrial function by scavenging hydrogen peroxide, and mitigating the oxidation of protein tyrosine phosphatases and lipid peroxidation. We further identify rosmarinic acid (RA) as a potent agonist of PRDX1. As revealed by the complex crystal structure, RA binds to PRDX1 and stabilizes its peroxidatic cysteine. RA alleviates NASH through specifically activating PRDX1's peroxidase activity. Thus, beyond revealing the molecular mechanism underlying PA promoting oxidative stress and NASH, our study suggests that boosting PRDX1's peroxidase activity is a promising intervention for treating NASH.

Trehalose Ameliorates Nonalcoholic Fatty Liver Disease by Regulating IRE1α-TFEB Signaling Pathway

Nonalcoholic fatty liver disease (NAFLD), characterized by hepatic lipid deposition, is one of the most prevalent chronic metabolic disorders globally, and its pharmaceutical treatments are still limited. Excessive lipid accumulation triggers endoplasmic reticulum (ER) stress and autophagy flux dysfunction, which are important mechanisms for NAFLD. Trehalose (Tre), a natural disaccharide, has been identified to reduce hepatic steatosis and glucose intolerance. However, its underlying mechanisms for NAFLD remain unclear. In this study, a high-fat-diet (HFD)-induced mouse NAFLD model and a saturated fatty acid palmitic acid (PA)-stimulated cell model were constructed. The results indicated that Tre supplementation ameliorated hepatocyte lipid deposition in vitro, as well as hepatic steatosis and hyperlipidemia in vivo. Mechanistically, Tre alleviated both autophagy flux dysfunction and endoplasmic reticulum (ER) stress. Under the stimulation of HFD or PA, Tre remarkably increased the expression and nucleic translocation of the lysosomal master protein transcription factor EB (TFEB), while decreasing the accumulation of p62 and also decreasing the ER stress markers (inositol-requiring enzyme 1 (IRE1α), XBP-1, CHOP, and BIP). Similar results were observed in an ER stressor tunicamycin (TM)-induced in vivo and in vitro models. In addition, the transcriptomic analysis of NAFLD patients revealed significant differences in ER stress-related and autophagy-related biomarkers, including TFEB, ATG7, IRE1α, and CHOP. Molecular docking results demonstrated a strong affinity between Tre and both IRE1α and TFEB. Overall, Tre protected hepatocytes from lipotoxicity-related ER stress and autophagy dysfunction, and its regulatory effect on the IRE1α-TFEB signaling pathway may be a critical mechanism. These findings suggest that Tre, as a bioactive substance with significant medicinal potential, holds considerable promise for drug development and clinical application in treating NAFLD.

Induction of steatosis in primary human hepatocytes recapitulates key pathophysiological aspects of metabolic dysfunction-associated steatotic liver disease

BACKGROUND & AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common cause of chronic liver disease. Owing to limited available treatment options, novel pre-clinical models for target selection and drug validation are warranted. We have established and extensively characterized a primary human steatotic hepatocyte in vitro model system that could guide the development of treatment strategies for MASLD.

METHODS

Cryopreserved primary human hepatocytes from five donors varying in sex and ethnicity were cultured with free fatty acids in a 3D collagen sandwich for 7 days and the development of MASLD was followed by assessing classical hepatocellular functions. As proof of concept, the effects of the drug firsocostat (GS-0976) on in vitro MASLD phenotypes were evaluated.

RESULTS

Incubation with free fatty acids induced steatosis, insulin resistance, mitochondrial dysfunction, inflammation, and alterations in prominent human gene signatures similar to patients with MASLD, indicating the recapitulation of human MASLD in this system. The application of firsocostat rescued clinically observed fatty liver disease pathologies, highlighting the ability of the in vitro system to test the efficacy and potentially characterize the mode of action of drug candidates.

CONCLUSIONS

Altogether, our human MASLD in vitro model system could guide the development and validation of novel targets and drugs for the treatment of MASLD.

IMPACT AND IMPLICATIONS

Due to low drug efficacy and high toxicity, clinical treatment options for metabolic dysfunction-associated steatotic liver disease (MASLD) are currently limited. To facilitate earlier stop-go decisions in drug development, we have established a primary human steatotic hepatocyte in vitro model. As the model recapitulates clinically relevant MASLD characteristics at high phenotypic resolution, it can serve as a pre-screening platform and guide target identification and validation in MASLD therapy.

Exploring Structural and Molecular Features of Sciatic Nerve Lesions in Diabetic Neuropathy: Unveiling Pathogenic Pathways and Targets

Lesioned fascicles (LFs) in the sciatic nerves of individuals with diabetic neuropathy (DN) correlate with clinical symptom severity. This study aimed to characterize the structural and molecular composition of these lesions to better understand DN pathogenesis. Sciatic nerves from amputees with and without type 2 diabetes (T2D) were examined using ex vivo magnetic resonance neurography, in vitro imaging, and proteomic analysis. Lesions were only found in T2D donors and exhibited significant structural abnormalities, including axonal degeneration, demyelination, and impaired blood-nerve barrier (BNB). Although non-LFs from T2D donors showed activation of neuroprotective pathways, LFs lacked this response and instead displayed increased complement activation via the classical pathway. The detection of liver-derived acute-phase proteins suggests that BNB disruption facilitates harmful interorgan communication between the liver and nerves. These findings reveal key molecular mechanisms contributing to DN and highlight potential targets for therapeutic intervention.

ARTICLE HIGHLIGHTS

Mechanisms and therapeutic implications of selective autophagy in nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease worldwide, whereas there is no approved drug therapy due to its complexity. Studies are emerging to discuss the role of selective autophagy in the pathogenesis of NAFLD, because the specificity among the features of selective autophagy makes it a crucial process in mitigating hepatocyte damage caused by aberrant accumulation of dysfunctional organelles, for which no other pathway can compensate.

AIM OF REVIEW

This review aims to summarize the types, functions, and dynamics of selective autophagy that are of particular importance in the initiation and progression of NAFLD. And on this basis, the review outlines the therapeutic strategies against NAFLD, in particular the medications and potential natural products that can modulate selective autophagy in the pathogenesis of this disease.

KEY SCIENTIFIC CONCEPTS OF REVIEW

The critical roles of lipophagy and mitophagy in the pathogenesis of NAFLD are well established, while reticulophagy and pexophagy are still being identified in this disease due to the insufficient understanding of their molecular details. As gradual blockage of autophagic flux reveals the complexity of NAFLD, studies unraveling the underlying mechanisms have made it possible to successfully treat NAFLD with multiple pharmacological compounds that target associated pathways. Overall, it is convinced that the continued research into selective autophagy occurring in NAFLD will further enhance the understanding of the pathogenesis and uncover novel therapeutic targets.

Novel insights into the role of quercetin and kaempferol from Carthamus tinctorius L. in the management of nonalcoholic fatty liver disease via NR1H4-mediated pathways

This study investigates the novel therapeutic potential of quercetin and kaempferol, two bioactive compounds derived from Carthamus tinctorius L., in treating nonalcoholic fatty liver disease (NAFLD) by modulating the bile acid receptor NR1H4 (Nuclear Receptor Subfamily 1 Group H Member 4) and its associated metabolic pathways. A rat model of NAFLD was established, and RNA sequencing and proteomics were carefully employed to identify differential gene expressions associated with the disease. The active components of Carthamus tinctorius L. were screened, followed by the construction of a comprehensive network that maps the interactions between these components, NR1H4 and NAFLD-related pathways. Both in vitro (using HepG2 cells) and in vivo experiments were conducted to evaluate the effects on NR1H4 expression levels through Western blot and RT-qPCR analyses. Our findings identify NR1H4 as a pivotal target in NAFLD. Network pharmacology analysis indicates that quercetin and kaempferol play crucial roles in combating NAFLD, with in vitro and in vivo experiments confirming their ability to mitigate hepatocyte steatosis by enhancing NR1H4 expression. Notably, the protective effects of these compounds were inhibited by the NR1H4 antagonist guggulsterone, highlighting the importance of NR1H4 upregulation. This study demonstrates the novel therapeutic efficacy of quercetin and kaempferol from Carthamus tinctorius L. in treating NAFLD through NR1H4 upregulation. This mechanism contributes to the regulation of lipid metabolism, improvement of liver function, reduction of inflammation, and alleviation of oxidative stress, offering a promising direction for future NAFLD treatment strategies.

Erhong Jiangzhi Decoction Inhibits Lipid Accumulation and Alleviates Nonalcoholic Fatty Liver Disease with Nrf2 Restoration Under Obesity

Background

Nonalcoholic fatty liver disease (NAFLD) refers to the liver pathological changes caused by excessive fat accumulation in hepatocytes owing to various reasons, which has become an emerging health challenge. Erhong Jiangzhi Decoction (EHJD) is a traditional Chinese medicine decoction. This study aims to investigate the therapeutic effect of EHJD on NAFLD.

Methods

NAFLD model was constructed by high-fat diet (HFD)-induced mice and oleic acid-induced HepG2 cells. Mice were intragastrically administered with EHJD and HepG2 cells were treated with EHJD drug-containing serum. The effects of EHJD on NAFLD were explored in vivo and in vitro. Histological assessment was performed by hematoxylin-eosin and oil red O staining. ELISA was exploited to detect the expression of lipid accumulation, liver function, inflammation, and oxidative stress related indicators. The expression of Nrf2/HO-1 pathway was detected by qRT-PCR and Western blot.

Results

In HFD-induced NAFLD mice, the body weight was increased, and liver/weight, inguinal fat/weight, and epididymal fat/weight were higher, while EHJD reduced them. Staining results exhibited that EHJD decreased inflammatory cell infiltration and oil red lipid droplets in HFD-induced mice. In addition, EHJD treatment suppressed TC, TG, ALT and AST levels; TNF-α, IL-1β, IL-6 and MDA levels were inhibited by EHJD, while GSH-Px, CAT and T-AOC levels were increased in NAFLD through the in vivo and in vitro experiments. The suppression of Nrf2 weakened the inhibitory effect of EHJD on lipid metabolism, liver injury, inflammation and oxidative stress.

Conclusion

EHJD had a protective effect on NAFLD by alleviating lipid accumulation and liver injury, inhibiting inflammation, and oxidative stress, which was achieved by the restoration of Nrf2.

The role of dietary modification in the prevention and management of metabolic dysfunction-associated fatty liver disease: An international multidisciplinary expert consensus

Metabolic dysfunction-associated fatty liver disease (MAFLD) or metabolic dysfunction-associated steatotic liver disease (MASLD), has become the leading cause of chronic liver disease worldwide. Optimal dietary intervention strategies for MAFLD are not standardized. This study aimed to achieve consensus on prevention of MAFLD through dietary modification. A multidisciplinary panel of 55 international experts, including specialists in hepatology, gastroenterology, dietetics, endocrinology and other medical specialties from six continents collaborated in a Delphi-based consensus development process. The consensus statements covered aspects ranging from epidemiology to mechanisms, management, and dietary recommendations for MAFLD. The recommended dietary strategies emphasize adherence to a balanced diet with controlled energy intake and personalized nutritional interventions, such as calorie restriction, high-protein, or low-carbohydrate diets. Specific dietary advice encouraged increasing the consumption of whole grains, plant-based proteins, fish, seafood, low-fat or fat-free dairy products, liquid plant oils, and deeply colored fruits and vegetables. Concurrently, it advised reducing the intake of red and processed meats, saturated and trans fats, ultra-processed foods, added sugars, and alcohol. Additionally, maintaining the Mediterranean or DASH diet, minimizing sedentary behavior, and engaging in regular physical activity are recommended. These consensus statements lay the foundation for customized dietary guidelines and proposing avenues for further research on nutrition and MAFLD.

Grape-Seed Proanthocyanidin Extract (GSPE) Modulates Diurnal Rhythms of Hepatic Metabolic Genes and Metabolites, and Reduces Lipid Deposition in Cafeteria-Fed Rats in a Time-of-Day-Dependent Manner

SCOPE

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a global health issue with increasing prevalence. Polyphenols, such as grape seed proanthocyanidin extract (GSPE), are bioactive compounds present in plants and represent an interesting therapeutical approach for MASLD.

METHODS AND RESULTS

This study questioned whether the timing of GSPE administration impacts liver diurnal metabolism and steatosis in a rat obesity model. Results from hepatic lipid profiling and diurnal metabolic gene expression and metabolomics reveal that rats fed with a cafeteria (CAF) diet show impaired glucose homeostasis and enhanced lipogenesis in the liver, contributing to liver steatosis. Chronic consumption of GSPE in the inactive or active phase is associated with beneficial effects as the restoration of rhythms of transcripts and metabolites is observed. However, only when given in the active phase, GSPE treatment decreases hepatic triglyceride levels. Using an in vitro hepatocyte model, the study identifies that catechin, one of the main phenolic compounds found in the GSPE extract, is a potential mediator in ameliorating the effects of CAF-induced liver steatosis.

CONCLUSION

Taken altogether, the findings show that the beneficial effects of GSPE on MASLD development depend on the treatment time.

Integrative Transcriptomics and Proteomics Analysis Reveals THRSP's Role in Lipid Metabolism

Background/Objectives: Abnormalities in lipid metabolism and endoplasmic reticulum (ER) stress are strongly associated with the development of a multitude of pathological conditions, including nonalcoholic fatty liver disease (NAFLD), diabetes mellitus, and obesity. Previous studies have indicated a potential connection between thyroid hormone responsive (THRSP) and lipid metabolism and that ER stress may participate in the synthesis of key regulators of adipogenesis. However, the specific mechanisms remain to be investigated. Methods: In this study, we explored the roles of THRSP in lipid metabolism by interfering with THRSP gene expression in mouse mesenchymal stem cells, comparing the effects on adipogenesis between control and interfered groups, and by combining transcriptomic and proteomic analysis. Results: Our results showed that the number of lipid droplets was significantly reduced after interfering with THRSP, and the expression levels of key regulators of adipogenesis, such as LPL, FABP4, PLIN1, and CIDEC, were significantly downregulated. Both transcriptomic and proteomic results showed that the differential genes (proteins) were enriched in the processes of lipolytic regulation, ER stress, cholesterol metabolism, sphingolipid metabolism, PPAR signaling pathway, and glycerophospholipid metabolism. The ER stress marker gene, ATF6, was the most significantly downregulated transcription factor. In addition, RT-qPCR validation indicated that the expression levels of PPAR signaling pathway gene SCD1; key genes of lipid droplet generation including LIPE, DGAT1, and AGPAT2; and ER stress marker gene ATF6 were significantly downregulated. Conclusions: These suggest that THRSP is involved in regulating ER stress and the PPAR signaling pathway, which is closely related to lipid synthesis and metabolism. Interfering with the expression of THRSP may be helpful in ameliorating the occurrence of diseases related to abnormalities in lipid metabolism.

Metabolic Dysfunction-Associated Steatotic Liver Disease in Chronic Hepatitis C Virus Infection: From Basics to Clinical and Nutritional Management

Metabolic dysfunction-associated steatotic liver disease (MASLD) is closely associated with obesity and other cardiometabolic risk factors. MASLD has rapidly become the most common cause of liver disease worldwide, currently affecting 38% of the global population. Excess weight causes chronic inflammation and the activation of different pathways involved in liver damage. MASLD can progress from simple steatosis to steatohepatitis, giving way to its inflammatory component, metabolic dysfunction-associated steatohepatitis (MASH), previously recognized as non-alcoholic steatosis hepatitis (NASH). Chronic hepatitis C virus (HCV) infection remains a significant challenge to liver health as it triggers hepatic inflammation, metabolic disruption, and hepatic steatosis. The convergence of MASLD and chronic HCV infection can significantly alter the course of liver disease and accelerate the progression to severe liver damage. Currently, HCV treatment has a high cure rate. However, in patients who achieve a sustained virological response after treatment with direct-acting antivirals, weight gain, and excessive calorie intake may contribute to increased liver steatosis and a higher risk of liver disease progression. Therefore, the effective clinical and nutritional management of HCV patients, both before and after viral eradication, is crucial to reducing the risk of death from hepatocellular carcinoma. Understanding the complex interactions between MASLD and HCV infection is crucial for managing these patients appropriately. Herein, host and viral mechanisms inducing liver damage during the coexistence of MASLD and HCV infection are described, and their therapeutic and dietary management are discussed.

Ultrasound evaluation of kidney and liver involvement in Bardet-Biedl syndrome

BACKGROUND

Bardet-Biedl syndrome (BBS) is a rare autosomal-recessive ciliopathy with pathogenic variants in 26 BBS genes. It affects multiple organs, including the kidney and liver, with varying degrees regarding extent and time of first manifestation. Structural renal anomalies are an early feature and end-stage kidney disease (ESKD) cumulates to 25% in adulthood. Early-onset hyperphagia-associated obesity is another major symptom and contributes to liver pathology, presenting as steatosis/fibrosis. Aim of this study is the evaluation of high-end ultrasound (US) technologies in BBS patients regarding their potential to discriminate liver and kidney tissue pathology at an early stage.

MATERIALS AND METHODS

Patients with genetically proven BBS were recruited from the University Children's Hospital of Essen and from BBS patient days hosted in Germany. Acute illness was an exclusion criterion. Clinical and laboratory data were extracted from patients' digital records or medical letters. High-resolution ultrasound (US) imaging was utilized, including attenuation imaging (ATI), shear wave elastography (SWE) and dispersion (SWD) of liver tissue.

RESULTS

49 BBS patients (24/49 male; 1.1-51.0 years, mean 17.8 years) were included in the study. Mean body weight (SDS 2.13 ± 1.33) and BMI (SDS 2.64 ± 1.18) were increased. Structural kidney abnormalities (dysplasia, cysts) were present in 75% (36/48), and persistent fetal lobulation in 44% (21/48). Renal function was impaired in 27% (13/49) of whom 3 had ESKD (kidney transplantation (n = 2), hemodialysis (n = 1)). Elevation of liver enzymes was detected in 38% (16/42). In 51% (25/49) ATI of liver tissue was increased, indicating hepatic steatosis, and correlated with BMI SDS, liver size, and enzymes. SWE was elevated in 61% (30/49), suggesting hepatic fibrosis, and it correlated with BMI and GGT. Patients with pathogenic variants in BBS10 showed a tendency towards higher ATI, reduced GFR, and higher BMI SDS.

CONCLUSIONS

We detected kidney and liver abnormalities in a higher percentage of BBS patients than previously reported, indicating a high sensitivity and diagnostic yield of the evaluated high-end US applications. ATI detected liver pathology early (partially prior to liver enzymes) and revealed differences related to the affected genes. Evidence of tissue pathology at an early stage may improve diagnostics and the evaluation of therapeutic approaches.

Decreasing the burden of non-alcoholic fatty liver disease: From therapeutic targets to drug discovery opportunities

Non-alcoholic fatty liver disease (NAFLD) presents a pervasive global pandemic, affecting approximately 25 % of the world's population. This grave health issue not only demands urgent attention but also stands as a significant economic concern on a global scale. The genesis of NAFLD can be primarily attributed to unhealthy dietary habits and a sedentary lifestyle, albeit certain genetic factors have also been recorded to contribute to its occurrence. NAFLD is characterized by fat accumulation in more than 5 % of hepatocytes according to histological analysis, or >5.6 % of lipid volume fraction in total liver weight in patients. The pathophysiology of NAFLD/non-alcoholic steatohepatitis (NASH) is multifactorial and the mechanisms underlying the progression to advanced forms remain unclear, thereby representing a challenge to disease therapy. Despite the substantial efforts from the scientific community and the large number of pre-clinical and clinical trials performed so far, only one drug was approved by the Food and Drug Administration (FDA) to treat NAFLD/NASH specifically. This review provides an overview of available information concerning emerging molecular targets and drug candidates tested in clinical studies for the treatment of NAFLD/NASH. Improving our understanding of NAFLD pathophysiology and pharmacotherapy is crucial not only to explore new molecular targets, but also to potentiate drug discovery programs to develop new therapeutic strategies. This knowledge endeavours scientific efforts to reduce the time for achieving a specific and effective drug for NAFLD or NASH management and improve patients' quality of life.

Chiglitazar attenuates high-fat diet-induced nonalcoholic fatty liver disease by modulating multiple pathways in mice

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide; however, effective intervention strategies for NAFLD are still unavailable. The present study sought to investigate the efficacy of chiglitazar, a pan-PPAR agonist, in protecting against NAFLD in mice and its underlying molecular mechanism. Male C57BL/6 J mice were fed a high-fat diet (HFD) for 8 weeks to generate NAFLD and the HFD was continued for an additional 10 weeks in the absence or presence of 5 mg/kg/d or 10 mg/kg/d chiglitazar by gavage. Chiglitazar significantly improved dyslipidemia and insulin resistance, ameliorated hepatic steatosis and reduced liver inflammation and oxidative stress in NAFLD mice. RNA-seq revealed that chiglitazar alleviated HFD-induced NAFLD in mice through multiple pathways, including fatty acid metabolism regulation, insulin signaling pathway, and AMPK signaling pathway. This study demonstrated the potential therapeutic effect of chiglitazar on NAFLD. Chiglitazar ameliorated NAFLD by modulating multiple pathways.

Hepatocyte-Specific Casein Kinase 1 Epsilon Ablation Ameliorates Metabolic Dysfunction-Associated Steatohepatitis by Up-Regulating Tumor Necrosis Factor Receptor-Associated Factor 3 in Mice

Casein kinase 1 epsilon (CK1ε), a member of the serine/threonine protein kinase family, phosphorylates a broad range of substrates. However, its role in the development of chronic liver diseases remains elusive. This study aimed to investigate the role of CK1ε in the development and progression of metabolic dysfunction-associated steatohepatitis (MASH). Hepatocyte-specific CK1ε knockout (CK1εΔHEP) mice were generated by crossbreeding mice with floxed CK1ε alleles (CK1εfl/fl) and Cre-expressing albumin mice. Mice were fed either a Western diet (WD) or a methionine- and choline-deficient diet to induce MASH. CK1εΔHEP was associated with a decreased severity of WD- or methionine- and choline-deficient diet-induced MASH, as confirmed by reduced incidence of hepatic lesions and significantly lower levels of alanine aminotransferase, aspartate aminotransferase, and proinflammatory cytokine tumor necrosis factor (TNF)-α. CK1εΔHEP WD-fed mice exhibited significant amelioration of total cholesterol, triglycerides, and de novo lipogenic genes, indicating that CK1ε could influence lipid metabolism. CK1εΔHEP WD-fed mice showed significantly down-regulated TNF receptor-associated factor (TRAF) 3, phosphorylated (p) transforming growth factor-β-activated kinase 1, p-TRAF-associated NF-κB activator (TANK)-binding kinase 1 (TBK1), and p-AKT levels, thereby affecting downstream mitogen-activated protein kinase signaling, indicating a potential mechanism for the observed rescue. Finally, pharmacologic inhibition of CK1ε with PF670462 improved palmitic acid-induced steatohepatitis in vitro and attenuated WD-induced metabolic profile in vivo. In conclusion, CK1ε up-regulates TNF receptor-associated factor 3, which, in turn, causes transforming growth factor-β-activated kinase 1-dependent signaling, amplifies downstream mitogen-activated protein kinase signaling, modifies p-c-Jun levels, and exacerbates inflammation, all of which are factors in WD-induced metabolic dysfunction-associated steatotic liver disease.

MAFLD-related hepatocellular carcinoma: Exploring the potent combination of immunotherapy and molecular targeted therapy

Hepatocellular carcinoma (HCC) is a common cause of cancer-related mortality and morbidity globally, and with the prevalence of metabolic-related diseases, the incidence of metabolic dysfunction-associated fatty liver disease (MAFLD) related hepatocellular carcinoma (MAFLD-HCC) continues to rise with the limited efficacy of conventional treatments, which has created a major challenge for HCC surveillance. Immune checkpoint inhibitors (ICIs) and molecularly targeted drugs offer new hope for advanced MAFLD-HCC, but the evidence for the use of both types of therapy in this type of tumour is still insufficient. Theoretically, the combination of immunotherapy, which awakens the body's anti-tumour immunity, and targeted therapies, which directly block key molecular events driving malignant progression in HCC, is expected to produce synergistic effects. In this review, we will discuss the progress of immunotherapy and molecular targeted therapy in MAFLD-HCC and look forward to the opportunities and challenges of the combination therapy.

Possible protective effect of natural flavanone naringenin-reduced graphene oxide nanosheets on nonalcoholic fatty liver disease

Utilizing naringenin as a safe, natural compound for reducing graphene oxide and to determine whether Nar-RGO more effectively mitigates the harmful effects of HFFD-induced NAFLD compared to crude naringenin. Using a straightforward experimental setup, we utilize the bioactive flavonoid naringenin (NAR) as the reducing agent to synthesize naringenin-reduced graphene oxide nanosheets (Nar-RGO). Naringenin loading on graphene oxide was validated using electroscopic methods (SEM and TEM) and zeta potential measurements. Utilization of reduced graphene oxide for naringenin encapsulation resulted in a significant improvement in hepatic steatosis, insulin resistance, oxidative stress, and signs of inflammation in HFFD-induced NAFLD compared to crude naringenin. This study demonstrates that Nar-RGO exhibits significantly greater efficacy compared to free naringenin. Therefore, it can be used as a promising medicine in counteracting high-fat-fructose diet (HFFD)-induced NAFLD.

Fagopyrum dibotrys extract improves nonalcoholic fatty liver disease via inhibition of lipogenesis and endoplasmic reticulum stress in high-fat diet-fed mice

OBJECTIVE

The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing, presenting a treatment challenge due to limited options. Endoplasmic reticulum (ER) stress and associated lipid metabolism disorders are main causes of NAFLD, making it important to inhibit ER stress for effective treatment. Fagopyrum dibotrys has hypolipidemic, anti-inflammatory and hepatoprotective properties, showing promise in treating NAFLD. However, its effects on ER stress in NAFLD remain unclear. This study used a high-fat diet (HFD) to establish NAFLD mouse models and supplemented with Fagopyrum dibotrys extract (FDE) to evaluate its therapeutic effect and underlying mechanisms.

RESULTS

We showed that FDE supplementation reduced the severity of hepatic steatosis and lowered triglycerides (TG) and total cholesterol (TC) levels in NAFLD mice. At the molecular level, FDE supplementation reduced hepatic lipid deposition by downregulating lipogenic markers (SREBP-1c, SCD1) and upregulating fatty acid oxidase CPT1α expression. Additionally, FDE treatment inhibited the overexpression of ER stress markers (GRP78, CHOP, and P-EIF2α) in NAFLD mice livers, and blocked the activation of the PERK-EIF2α-CHOP pathway, demonstrating its role in maintaining ER homeostasis. Considering that activation of the PERK pathway could exacerbate lipid deposition, our findings suggest that FDE has a protective effect against hepatic steatosis in NAFLD mice by attenuating ER stress, and the potential mechanism is through inhibiting the PERK pathway.

Circulating small non-coding RNAs are associated with the insulin-resistant and obesity-related type 2 diabetes clusters

AIM

To uncover differences in small non-coding RNAs (sncRNAs) in individuals with type 2 diabetes (T2D) categorized into five clusters based on individual characteristics, which may aid in the identification of those prone to rapid progression.

MATERIALS AND METHODS

In the Hoorn Diabetes Care System (DCS) cohort, participants were clustered by age, body mass index (BMI), and glycated haemoglobin, C-peptide and high-density lipoprotein (HDL) cholesterol levels, yielding severe insulin-deficient diabetes, severe insulin-resistant diabetes (SIRD), mild obesity-related diabetes (MOD), mild diabetes, and mild diabetes with high HDL cholesterol clusters (n = 412). Utilizing plasma sncRNA-sequencing, we identified distinct cluster-specific sncRNAs. Validation was performed in a smaller DCS Hoorn dataset (n = 138). To elucidate their potential functions, we examined tissue expression, identified potential targets or (co-)regulated proteins, conducted gene set enrichment analyses on the targets through Reactome, and examined tissue expression of the (co-)regulated proteins.

RESULTS

The insulin-resistant cluster exhibited aberrant expression of 10 sncRNAs, while the high BMI cluster featured eight differentially expressed sncRNAs. Multiple (co-)regulated proteins were identified for sncRNAs associated with both clusters. Proteins associated with both clusters showed enrichment for metabolism. Proteins that specifically and only associated with the SIRD cluster showed enrichment for immune-related signalling. Furthermore, MOD cluster-specific associated proteins showed enrichment for the complement system.

CONCLUSIONS

Our research showed differential sncRNA levels among type 2 diabetes clusters. This may reflect and could deepen our understanding of molecular mechanisms, in development, progression, and risk factors for each cluster.

Impact of silymarin-supplemented cookies on liver enzyme and inflammatory markers in non-alcoholic fatty liver disease patients

Nonalcoholic fatty liver disease (NAFLD) is a growing public health concern characterized by fat accumulation and severe disorders like nonalcoholic steatohepatitis (NASH), which are influenced by obesity, inflammatory processes, and metabolic pathways. This research investigates the potential of silymarin-supplemented cookies in managing NAFLD by evaluating their impact on liver enzyme activity, inflammatory markers, and lipid profiles. A clinical trial in Lahore, Pakistan, involved 64 NAFLD patients. Participants were divided into placebo and three treatment groups, with the latter receiving silymarin-supplemented cookies for 3 months. The study assessed liver enzyme levels and inflammatory markers, at baseline and after the intervention, utilizing statistical analyses to evaluate differences. The lipid profile and renal function test (RFT) were also measured at baseline and after 3 months in each group for safety assessment. After 3 months, the treatment groups indicated more significant decreases in liver enzymes compared to the placebo group (p ≤ .05). Treatment 3 showed significant reductions in alanine aminotransferase (ALT) (64.39-49.38 U/L) and aspartate aminotransferase (AST) (61.53-45.38 U/L). Treatment 3 also showed improvements in alkaline phosphatase (ALP) levels and the AST/ALT ratio. Additionally, the treatment group demonstrated a significant reduction in inflammatory markers. Treatment 3 showed a significant decrease in C-reactive protein (CRP) (6.32-3.39 mg/L) and erythrocyte sedimentation rate (ESR) (38.72-23.86 mm/h), indicating that individuals with NAFLD may benefit from the intervention's potential benefits in lowering inflammation. The study revealed that an intervention significantly improved the inflammatory markers, liver enzymes, and lipid profiles of NAFLD participants, suggesting potential benefits for liver health.

ER-mitochondria contact sites regulate hepatic lipogenesis via Ip3r-Grp75-Vdac complex recruiting Seipin

BACKGROUND

Mitochondria and endoplasmic reticulum (ER) contact sites (MERCS) constitute a functional communication platform for ER and mitochondria, and they play a crucial role in the lipid homeostasis of the liver. However, it remains unclear about the exact effects of MERCs on the neutral lipid synthesis of the liver.

METHODS

In this study, the role and mechanism of MERCS in palmitic acid (PA)-induced neutral lipid imbalance in the liver was explored by constructing a lipid metabolism animal model based on yellow catfish. Given that the structural integrity of MERCS cannot be disrupted by the si-mitochondrial calcium uniporter (si-mcu), the MERCS-mediated Ca2+ signaling in isolated hepatocytes was intercepted by transfecting them with si-mcu in some in vitro experiments.

RESULTS

The key findings were: (1) Hepatocellular MERCs sub-proteome analysis confirmed that, via activating Ip3r-Grp75-voltage-dependent anion channel (Vdac) complexes, excessive dietary PA intake enhanced hepatic MERCs. (2) Dietary PA intake caused hepatic neutral lipid deposition by MERCs recruiting Seipin, which promoted lipid droplet biogenesis. (3) Our findings provide the first proof that MERCs recruited Seipin and controlled hepatic lipid homeostasis, depending on Ip3r-Grp75-Vdac-controlled Ca2+ signaling, apart from MERCs's structural integrity. Noteworthy, our results also confirmed these mechanisms are conservative from fish to mammals.

CONCLUSIONS

The findings of this study provide a new insight into the regulatory role of MERCS-recruited SEIPIN in hepatic lipid synthesis via Ip3r-Grp75-Vdac complex-mediated Ca2+ signaling, highlighting the critical contribution of MERCS in hepatic lipid homeostasis.

Leveraging adrenergic receptor blockade for enhanced nonalcoholic fatty liver disease treatment via a biomimetic nanoplatform

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive lipid accumulation, steatosis and fibrosis. Sympathetic nerves play a critical role in maintaining hepatic lipid homeostasis and regulating fibrotic progression through adrenergic receptors expressed by hepatocytes and hepatic stellate cells; however, the use of sympathetic nerve-focused strategies for the treatment of NAFLD is still in the infancy. Herein, a biomimetic nanoplatform with ROS-responsive and ROS-scavenging properties was developed for the codelivery of retinoic acid (RA) and the adrenoceptor antagonist labetalol (LA). The nanoplatform exhibited improved accumulation and sufficient drug release in the fibrotic liver, thereby achieving precise codelivery of drugs. Integration of adrenergic blockade effectively interrupted the vicious cycle of sympathetic nerves with hepatic stellate cells (HSCs) and hepatocytes, which not only combined with RA to restore HSCs to a quiescent state but also helped to reduce hepatic lipid accumulation. We demonstrated the excellent ability of the biomimetic nanoplatform to ameliorate liver inflammation, fibrosis and steatosis. Our work highlights the tremendous potential of a sympathetic nerve-focused strategy for the management of NAFLD and provides a promising nanoplatform for the treatment of NAFLD.

Glucagon-like peptide-1 receptor: mechanisms and advances in therapy

The glucagon-like peptide-1 (GLP-1) receptor, known as GLP-1R, is a vital component of the G protein-coupled receptor (GPCR) family and is found primarily on the surfaces of various cell types within the human body. This receptor specifically interacts with GLP-1, a key hormone that plays an integral role in regulating blood glucose levels, lipid metabolism, and several other crucial biological functions. In recent years, GLP-1 medications have become a focal point in the medical community due to their innovative treatment mechanisms, significant therapeutic efficacy, and broad development prospects. This article thoroughly traces the developmental milestones of GLP-1 drugs, from their initial discovery to their clinical application, detailing the evolution of diverse GLP-1 medications along with their distinct pharmacological properties. Additionally, this paper explores the potential applications of GLP-1 receptor agonists (GLP-1RAs) in fields such as neuroprotection, anti-infection measures, the reduction of various types of inflammation, and the enhancement of cardiovascular function. It provides an in-depth assessment of the effectiveness of GLP-1RAs across multiple body systems-including the nervous, cardiovascular, musculoskeletal, and digestive systems. This includes integrating the latest clinical trial data and delving into potential signaling pathways and pharmacological mechanisms. The primary goal of this article is to emphasize the extensive benefits of using GLP-1RAs in treating a broad spectrum of diseases, such as obesity, cardiovascular diseases, non-alcoholic fatty liver disease (NAFLD), neurodegenerative diseases, musculoskeletal inflammation, and various forms of cancer. The ongoing development of new indications for GLP-1 drugs offers promising prospects for further expanding therapeutic interventions, showcasing their significant potential in the medical field.

Vaccinium spp. Berries in the Prevention and Treatment of Non-Alcoholic Fatty Liver Disease: A Comprehensive Update of Preclinical and Clinical Research

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disorder marked by the buildup of triacylglycerols (TGs) in the liver. It includes a range of conditions, from simple steatosis to more severe forms like non-alcoholic steatohepatitis (NASH), which can advance to fibrosis, cirrhosis, and hepatocellular carcinoma. NAFLD's prevalence is rising globally, estimated between 10% and 50%. The disease is linked to comorbidities such as obesity, type 2 diabetes, insulin resistance, and cardiovascular diseases and currently lacks effective treatment options. Therefore, researchers are focusing on evaluating the impact of adjunctive herbal therapies in individuals with NAFLD. One herbal therapy showing positive results in animal models and clinical studies is fruits from the Vaccinium spp. genus. This review presents an overview of the association between consuming fruits, juices, and extracts from Vaccinium spp. and NAFLD. The search used the following keywords: ((Vaccinium OR blueberry OR bilberry OR cranberry) AND ("non-alcoholic fatty liver disease" OR "non-alcoholic steatohepatitis")). Exclusion criteria included reviews, research notes, book chapters, case studies, and grants. The review included 20 studies: 2 clinical trials and 18 studies on animals and cell lines. The findings indicate that juices and extracts from Vaccinium fruits and leaves have significant potential in addressing NAFLD by improving lipid and glucose metabolism and boosting antioxidant and anti-inflammatory responses. In conclusion, blueberries appear to have the potential to alleviate NAFLD, but more clinical trials are needed to confirm these benefits.

Dietary patterns in the progression of metabolic dysfunction-associated fatty liver disease to advanced liver disease: a prospective cohort study

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a significant health problem. Dietary intervention plays an important role in patients with MAFLD.

OBJECTIVES

We aimed to provide a reference for dietary patterns in patients with MAFLD.

METHODS

The presence of MAFLD was determined in the United Kingdom Biobank cohort. Nine dietary pattern scores were derived from the dietary records. Multivariable Cox regression models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). The contrast test was employed to calculate the heterogeneity across MAFLD statuses.

RESULTS

We identified 175,300 patients with MAFLD at baseline. Compared with non-MAFLD, MAFLD was significantly associated with chronic liver disease (CLD) (HR: 3.48; 95% CI: 3.15, 3.84), severe liver disease (SLD) (HR: 2.87; 95% CI: 2.63, 3.14), liver cancer (HR: 1.93; 95% CI: 1.67, 2.23), and liver-related death (LRD) (HR: 1.93; 95% CI: 1.67, 2.23). In the overall cohort, the alternate Mediterranean diet (aMED) (HRCLD: 0.53; 95% CI: 0.37, 0.76; HRSLD: 0.52; 95% CI: 0.37, 0.72), planetary health diet (PHD) (HRCLD: 0.62; 95% CI: 0.47, 0.81; HRSLD: 0.65; 95% CI: 0.51, 0.83), plant-based low-carbohydrate diet (pLCD) (HRCLD: 0.65; 95% CI: 0.49, 0.86; HRSLD: 0.66; 95% CI: 0.51, 0.85), and healthful plant-based diet index (hPDI) (HRCLD: 0.63; 95% CI: 0.47, 0.84; HRSLD: 0.61; 95% CI: 0.47, 0.78) were associated with a lower risk of CLD and SLD. Additionally, unhealthful plant-based diet index (uPDI) was associated with increased risk of CLD (HR: 1.42; 95% CI: 1.09,1.85), SLD (HR: 1.50; 95% CI: 1.19, 1.90), and LRD (HR: 1.88; 95% CI: 1.28-2.78). The aforementioned associations remained consistently strong within the MAFLD subgroup while exhibiting less pronounced in the non-MAFLD group. However, no significant heterogeneity was observed across different MAFLD statuses.

CONCLUSIONS

These findings highlight the detrimental effects of MAFLD on the development of subsequent liver diseases and the importance of dietary patterns in managing MAFLD.

Association between urinary polycyclic aromatic hydrocarbons and risk of metabolic associated fatty liver disease

OBJECTIVE

To investigate the effect of urinary PAHs on MAFLD.

METHODS

The study included 3,136 adults from the National Health and Nutrition Examination Survey (NHANES) conducted between 2009 and 2016. Among them, 1,056 participants were diagnosed with MAFLD and were designated as the case group. The analysis of the relationship between monohydroxy metabolites of seven PAHs in urine and MAFLD was carried out using logistic regression and Bayesian kernel regression (BKMR) models.

RESULTS

In single-pollutant models, the concentration of 2-hydroxynaphthalene (2-OHNAP) was positively correlated with MAFLD (OR = 1.47, 95% CI 1.18, 1.84), whereas 3-hydroxyfluorene (3-OHFLU) and 1-hydroxypyrene (1-OHPYR) demonstrated a negative correlation with MAFLD (OR = 0.59, 95% CI 0.48 0.73; OR = 0.70, 95% CI 0.55, 0.89). Conversely, in multi-pollutant models, 2-OHNAP, 2-hydroxyfluorene (2-OHFLU), 2-hydroxyphenanthrene, and 3-hydroxyphenanthrene (2&3-OHPHE) displayed positive correlations with MAFLD (OR = 6.17, 95% CI 3.15, 12.07; OR = 2.59, 95% CI 1.37, 4.89). However, 3-OHFLU and 1-OHPYR continued to exhibit negative correlations with MAFLD (OR = 0.09, 95% CI 0.05, 0.15; OR = 0.62, 95% CI 0.43, 0.88). Notably, the BKMR analysis mixtures approach did not indicate a significant joint effect of multiple PAHs on MAFLD, but identified interactions between 3-OHFLU and 2-OHFLU, 1-OHPYR and 2-OHFLU, and 1-OHPYR and 3-OHFLU.

CONCLUSION

No significant association was found between mixed PAHs exposure and the risk of MAFLD. However, interactions were observed between 3-OHFLU and 2-OHFLU. Both 2-OHFLU and 2&3-OHPHE exposure are significant risk factors for MAFLD, whereas 3-OHFLU is a key protective factor for the disease.

ELOVL1 is upregulated and promotes tumor growth in hepatocellular carcinoma through regulating PI3K-AKT-mTOR signaling

Background

The functions of the ELOVLs are mainly involved in the elongation of saturated and polyunsaturated fatty acids, thus influencing the metabolism of fatty acids. Abnormal lipid metabolism may result in NAFLD and NASH, which may lead to cirrhosis and liver cancer. These results suggest that ELOVLs-mediated metabolism might be involved in the development of HCC. The purpose of this study was to study the expression and function of ELOVL1 in human liver cancer.

Method

Using TCGA, GEPIA and other databases, we analyzed the relationship between the expression of ELOVL1 and liver cancer. The expression of ELOVL1 was detected by immunohistochemical method and Western blot method in hepatic carcinoma and hepatic carcinoma cells. Then, the effects of ELOVL1 on proliferation, apoptosis and invasion in vitro and in vivo were investigated by means of different methods.

Result

Our results indicate that ELOVL1 is more highly expressed in liver cancer than in normal tissues. Survival analysis showed that OS and DSS were shorter in patients with high ELOVL1 expression than in those with low expression. Multivariate Cox analysis further demonstrated that over-expression of ELOVL1 was an independent risk factor for overall survival in HCC. The results of ROC also confirmed the value of ELOVL1 in the diagnosis of liver cancer. The results of KEGG enrichment and GSEA indicate that ELOVL1 is associated with lipid metabolism and NAFLD, as well as PPAR, PI3K-AKT-mTOR. Compared with the control group, it was found that silencing ELOVL1 in Huh7 and HepG2 cells could inhibit the growth of cells, promote the apoptosis and decrease the metastasis and invasion. Changes in ELOVL1 induced cell proliferation and metastasis may be related to PI3K/AKT/mTOR. Low expression of ELOVL1 inhibited the growth of xenograft tumors in hepatocellular carcinoma xenograft model.

Conclusion

Our data indicate that the activation of PI3K/AKT/mTOR pathway in HCC may contribute to the promotion of cancer. Thus, ELOVL1 may be a promising therapeutic target for HCC.

A comprehensive framework for managing metabolic dysfunction-associated steatotic liver disease: analyzing novel risk factors and advances in nanotechnology-based treatments and diagnosis

Metabolic dysfunction-associated steatotic liver disease (MASLD) presents a growing global health challenge requiring innovative approaches for effective management. This comprehensive review examines novel risk factors, including environmental pollutants like heavy metals, and underscores the complexity of personalized medicine tailored to individual patient profiles, influenced by gender and sex differences. Traditional treatments for MASLD, such as glucose- and lipid-lowering agents, show mixed results, highlighting the necessity for larger, long-term studies to establish safety and efficacy. Alternative therapies, including antioxidants, stem cells, and antiplatelets, although promising, demand extensive clinical trials for validation. This review highlights the importance of personalized medicine, considering individual variations and specific factors such as gender and sex, to optimize treatment responses. The shift from metabolic-associated fatty liver disease (MAFLD) to MASLD terminology underscores the metabolic components of the disease, aligning with the multiple-hit theory and highlighting the necessity for comprehensive risk factor management. Our vision advocates for an integrated approach to MASLD, encompassing extensive risk factor analysis and the development of safer, more effective treatments. Primary prevention and awareness initiatives are crucial in addressing the rising prevalence of MASLD. Future research must prioritize larger, long-term studies and personalized medicine principles to ensure the effective use of emerging therapies and technologies. The review underscores the need for continuous exploration and innovation, balancing the benefits and challenges of nanotechnology, to combat MASLD and improve patient outcomes comprehensively.

Obesity and MASLD: Is weight loss the (only) key to treat metabolic liver disease?

Metabolic dysfunction-associated steatotic liver disease (MASLD) closely associates with obesity and type 2 diabetes. Lifestyle intervention and bariatric surgery aiming at substantial weight loss are cornerstones of MASLD treatment by improving histological outcomes and reducing risks of comorbidities. Originally developed as antihyperglycemic drugs, incretin (co-)agonists and SGLT2 inhibitors also reduce steatosis and cardiorenovascular events. Certain incretin agonists effectively improve histological features of MASLD, but not fibrosis. Of note, beneficial effects on MASLD may not necessarily require weight loss. Despite moderate weight gain, one PPARγ agonist improved adipose tissue and MASLD with certain benefit on fibrosis in post-hoc analyses. Likewise, the first THRβ-agonist was recently provisionally approved because of significant improvements of MASLD and fibrosis. We here discuss liver-related and metabolic effects induced by different MASLD treatments and their association with weight loss. Therefore, we compare results from clinical trials on drugs acting via weight loss (incretin (co)agonists, SGLT2 inhibitors) with those exerting no weight loss (pioglitazone; resmetirom). Furthermore, other drugs in development directly targeting hepatic lipid metabolism (lipogenesis inhibitors, FGF21 analogs) are addressed. Although THRβ-agonism may effectively improve hepatic outcomes, MASLD treatment concepts should consider all cardiometabolic risk factors for effective reduction of morbidity and mortality in the affected people.

Post mortem analysis of hepatic volume and lipid content by magnetic resonance imaging and spectroscopy in fixed murine neonates

Maternal obesity and hyperglycemia are linked to an elevated risk for obesity, diabetes, and steatotic liver disease in the adult offspring. To establish and validate a noninvasive workflow for perinatal metabolic phenotyping, fixed neonates of common mouse strains were analyzed postmortem via magnetic resonance imaging (MRI)/magnetic resonance spectroscopy (MRS) to assess liver volume and hepatic lipid (HL) content. The key advantage of nondestructive MRI/MRS analysis is the possibility of further tissue analyses, such as immunohistochemistry, RNA extraction, and even proteomics, maximizing the data that can be gained per individual and therefore facilitating comprehensive correlation analyses. This study employed an MRI and 1H-MRS workflow to measure liver volume and HL content in 65 paraformaldehyde-fixed murine neonates at 11.7 T. Liver volume was obtained using semiautomatic segmentation of MRI acquired by a RARE sequence with 0.5-mm slice thickness. HL content was measured by a STEAM sequence, applied with and without water suppression. T1 and T2 relaxation times of lipids and water were measured for respective correction of signal intensity. The HL content, given as CH2/(CH2 + H2O), was calculated, and the intrasession repeatability of the method was tested. The established workflow yielded robust results with a variation of ~3% in repeated measurements for HL content determination. HL content measurements were further validated by correlation analysis with biochemically assessed triglyceride contents (R2 = 0.795) that were measured in littermates. In addition, image quality also allowed quantification of subcutaneous adipose tissue and stomach diameter. The highest HL content was measured in C57Bl/6N (4.2%) and the largest liver volume and stomach diameter in CBA (53.1 mm3 and 6.73 mm) and NMRI (51.4 mm3 and 5.96 mm) neonates, which also had the most subcutaneous adipose tissue. The observed effects were independent of sex and litter size. In conclusion, we have successfully tested and validated a robust MRI/MRS workflow that allows assessment of morphology and HL content and further enables paraformaldehyde-fixed tissue-compatible subsequent analyses in murine neonates.

Excess cardiovascular mortality in men with non-alcoholic fatty liver disease: A cause for concern!

Non-alcoholic fatty liver disease (NAFLD) has emerged as the commonest cause of chronic liver disease worldwide in recent years. With time, our understanding of NAFLD has evolved from an isolated liver condition to a systemic disease with significant manifestations beyond the liver. Amongst them, cardiovascular diseases (CVDs) are the most important and clinically relevant. Recent research supports a strong independent link between NALFD and CVD beyond the shared risk factors and pathophysiology. Female sex hormones are well known to not only protect against CVD in pre-menopausal females, but also contribute to improved adipose tissue function and preventing its systemic deposition. Recent research highlights the increased risk of major adverse cardiovascular-cerebral events (MACCE) amongst male with NAFLD compared to females. Further, racial variation was observed in MACCE outcomes in NAFLD, with excess mortality in the Native Americans and Asian Pacific Islanders compared to the other races.

PIM1 alleviated liver oxidative stress and NAFLD by regulating the NRF2/HO-1/NQO1 pathway

AIMS

Non-alcoholic fatty liver disease (NAFLD) has risen as a significant global public health issue, for which vertical sleeve gastrectomy (VSG) has become an effective treatment method. The study sought to elucidate the processes through which PIM1 mitigates the advancement of NAFLD. The Pro-viral integration site for Moloney murine leukemia virus 1 (PIM1) functions as a serine/threonine kinase. Bioinformatics analysis revealed that reduced PIM1 expression in NAFLD.

METHODS

To further prove the role of PIM1 in NAFLD, an in-depth in vivo experiment was performed, in which male C57BL/6 mice were randomly grouped to receive a normal or high-fat diet for 24 weeks. They were operated or delivered the loaded adeno-associated virus which the PIM1 was overexpressed (AAV-PIM1). In an in vitro experiment, AML12 cells were treated with palmitic acid to induce hepatic steatosis.

KEY FINDINGS

The results revealed that the VSG surgery and virus delivery of mice alleviated oxidative stress, and apoptosis in vivo. For AML12 cells, the levels of oxidative stress, apoptosis, and lipid metabolism were reduced via PIM1 upregulation. Moreover, ML385 treatment resulted in the downregulation of the NRF2/HO-1/NQO1 signaling cascade, indicating that PIM1 mitigates NAFLD by targeting this pathway.

SIGNIFICANCE

PIM1 alleviated mice liver oxidative stress and NAFLD induced by high-fat diet by regulating the NRF2/HO-1/NQO1 signaling Pathway.

Exploring Fibrosis Pathophysiology in Lean and Obese Metabolic-Associated Fatty Liver Disease: An In-Depth Comparison

While obesity-related nonalcoholic fatty liver disease (NAFLD) is linked with metabolic dysfunctions such as insulin resistance and adipose tissue inflammation, lean NAFLD more often progresses to liver fibrosis even in the absence of metabolic syndrome. This review aims to summarize the current knowledge regarding the mechanisms of liver fibrosis in lean NAFLD. The most commonly used lean NAFLD models include a methionine/choline-deficient (MCD) diet, a high-fat diet with carbon tetrachloride (CCl4), and a high-fructose and high-cholesterol diet. The major pro-fibrogenic mechanisms in lean NAFLD models include increased activation of the extracellular signal-regulated kinase (ERK) pathway, elevated expression of α-smooth muscle actin (α-SMA), collagen type I, and TGF-β, and modulation of fibrogenic markers such as tenascin-X and metalloproteinase inhibitors. Additionally, activation of macrophage signaling pathways promoting hepatic stellate cell (HSC) activation further contributes to fibrosis development. Animal models cannot cover all clinical features that are evident in patients with lean or obese NAFLD, implicating the need for novel models, as well as for deeper comparisons of clinical and experimental studies. Having in mind the prevalence of fibrosis in lean NAFLD patients, by addressing specific pathways, clinical studies can reveal new targeted therapies along with novel biomarkers for early detection and enhancement of clinical management for lean NAFLD patients.

Prolonged Cold Exposure Negatively Impacts Atlantic Salmon (Salmo salar) Liver Metabolism and Function

Large-scale mortality events have occurred during the winter in Atlantic salmon sea cages in Eastern Canada and Iceland. Thus, in salmon held at 3 °C that were apparently healthy (i.e., asymptomatic) and that had 'early' and 'advanced' symptoms of 'winter syndrome'/'winter disease' (WS/WD), we measured hepatic lipid classes and fatty acid levels, and the transcript expression of 34 molecular markers of fatty liver disease (FLD; a clinical sign of WS/WD). In addition, we correlated our results with previously reported characteristics associated with this disease's progression in these same individuals. Total lipid and triacylglycerol (TAG) levels increased by ~50%, and the expression of 32 of the 34 genes was dysregulated, in fish with symptoms of FLD. TAG was positively correlated with markers of inflammation (5loxa, saa5), hepatosomatic index (HSI), and plasma aspartate aminotransferase levels, but negatively correlated with genes related to lipid metabolism (elovl5b, fabp3a, cd36c), oxidative stress (catc), and growth (igf1). Multivariate analyses clearly showed that the three groups of fish were different, and that saa5 was the largest contributor to differences. Our results provide a number of biomarkers for FLD in salmon, and very strong evidence that prolonged cold exposure can trigger FLD in this ecologically and economically important species.

The role and mechanism of pyroptosis and potential therapeutic targets in non-alcoholic fatty liver disease (NAFLD)

Non-alcoholic fatty liver disease (NAFLD) is a clinical pathological syndrome characterized by the excessive accumulation of fat within liver cells, which can progress to end-stage liver disease in severe cases, posing a threat to life. Pyroptosis is a distinct, pro-inflammatory form of cell death, differing from traditional apoptosis. In recent years, there has been growing research interest in the association between pyroptosis and NAFLD, encompassing the mechanisms and functions of pyroptosis in the progression of NAFLD, as well as potential therapeutic targets. Controlled pyroptosis can activate immune cells, eliciting host immune responses to shield the body from harm. However, undue activation of pyroptosis may worsen inflammatory responses, induce cellular or tissue damage, disrupt immune responses, and potentially impact liver function. This review elucidates the involvement of pyroptosis and key molecular players, including NOD-like receptor thermal protein domain associated protein 3(NLRP3) inflammasome, gasdermin D (GSDMD), and the caspase family, in the pathogenesis and progression of NAFLD. It emphasizes the promising prospects of targeting pyroptosis as a therapeutic approach for NAFLD and offers valuable insights into future directions in the field of NAFLD treatment.

Azorella compacta Organic Extracts Exacerbate Metabolic Dysfunction-Associated Fatty Liver Disease in Mice Fed a High-Fat Diet

Azorella compacta (A. compacta) is a shrub of the Andean Altiplano of Bolivia, Chile and Peru, consumed by local communities as a traditional medicine for several maladies such as diabetes, hepatic and inflammatory diseases. A. compacta is rich in mulinane- and azorellane-type diterpenoids. For two of these, acute hypoglycemic effects have been described, but the impact of A. compacta diterpenoids on fatty liver disease has not been investigated. Therefore, A. compacta organic fractions were prepared using petroleum ether, dichloromethane and methanol. Their content was characterized by UHPLC/MS, revealing the presence of ten diterpenoids, mainly mulinic acid, azorellanol and mulin-11,13-diene. Next, mice fed with a high-fat diet (HFD), a model of metabolic dysfunction-associated fatty liver disease (MAFLD), received one of the fractions in drinking water for two weeks. After this treatment, hepatic parameters were evaluated. The A. compacta fractions did not reduce hyperglycemia or body weight in the HFD-fed mice but increased the serum levels of hepatic transaminases (AST and ALT), reduced albumin and increased bilirubin, indicating hepatic damage, while histopathological alterations such as steatosis, inflammation and necrosis generated by the HFD were, overall, not ameliorated by the fractions. These results suggest that organic A. compacta extracts may generate hepatic complications in patients with MAFLD.

PNPLA3 is a triglyceride lipase that mobilizes polyunsaturated fatty acids to facilitate hepatic secretion of large-sized very low-density lipoprotein

The I148M variant of PNPLA3 is closely associated with hepatic steatosis. Recent evidence indicates that the I148M mutant functions as an inhibitor of PNPLA2/ATGL-mediated lipolysis, leaving the role of wild-type PNPLA3 undefined. Despite showing a triglyceride hydrolase activity in vitro, PNPLA3 has yet to be established as a lipase in vivo. Here, we show that PNPLA3 preferentially hydrolyzes polyunsaturated triglycerides, mobilizing polyunsaturated fatty acids for phospholipid desaturation and enhancing hepatic secretion of triglyceride-rich lipoproteins. Under lipogenic conditions, mice with liver-specific knockout or acute knockdown of PNPLA3 exhibit aggravated liver steatosis and reduced plasma VLDL-triglyceride levels. Similarly, I148M-knockin mice show decreased hepatic triglyceride secretion during lipogenic stimulation. Our results highlight a specific context whereby the wild-type PNPLA3 facilitates the balance between hepatic triglyceride storage and secretion, and suggest the potential contribution of a loss-of-function by the I148M variant to the development of fatty liver disease in humans.

Preventing High Fat Diet-Induced Obesity and Related Hepatic Steatosis by Chlorin e6-Mediated Photodynamic Therapy

Obesity and its associated hepatic steatosis have become a global concern, posing numerous health hazards. Photodynamic therapy (PDT) is a unique approach that promotes anti-obesity by releasing intracellular fat. Chlorin e6 (Ce6)-PDT was tested for its anti-obesity properties in male ovariectomized (OVX) beagle dogs, as well as male C57BL/6 and Balb/c mice. The 12 OVX beagles were randomly assigned to one of four groups: high-fat diet (HFD) only, Ce6 only, Ce6 + 10 min of light-emitting diode light (LED) treatment, and Ce6 + 15 min of light treatment. We assessed several parameters, such as body weight, adipose tissue morphology, serum biochemistry, and body fat content analysis by computed tomography (CT) scan in HFD-fed beagle dogs. At the end of the study period, dogs that were treated for 35 days with Ce6 and exposed to LED irradiation (660 nm) either for 10 min (Ce6 + 10 min of light) or for 15 min (Ce6 + 15 min of light) had decreased body weight, including visceral and subcutaneous fats, lower aspartate transaminase (AST)/alanine transaminase (ALT) ratios, and a reduction in the area of individual adipocytes with a concomitant increase in the number of adipocytes. Furthermore, C57BL/6 male mice following an HFD diet were effectively treated by Ce6-PDT treatment through a reduction in weight gain and fat accumulation. Meanwhile, Ce6-PDT attenuated hepatocyte steatosis by decreasing the epididymal adipose tissue and balloon degeneration in hepatocytes in HFD-fed Balb/c mice. Taken together, our results support the idea that Ce6-PDT is a promising therapeutic strategy for the recovery of obesity and obesity-related hepatic steatosis.

Deciphering the molecular pathways of saroglitazar: A dual PPAR α/γ agonist for managing metabolic NAFLD

Saroglitazar (SARO), a dual peroxisome proliferator activated receptor (PPAR)-α/γ agonist, has been used to treat metabolic diseases such as insulin resistance and diabetic dyslipidemia in patients with non-alcoholic fatty liver disease (NAFLD). SARO, administered at a dose of 4 mg/day, has been consistently studied in clinical trials with different time points ranging from 4 to 24 weeks with NAFLD patients. Due to its PPAR-γ agonistic action, SARO prevents adipose tissue-mediated fatty acid delivery to the liver by increasing insulin sensitivity and regulating adiponectin and leptin levels in adipose tissue. In hepatocytes, SARO induces fatty acid β-oxidation in mitochondria and transcriptionally activates lipid metabolizing genes in peroxisomes. SARO inhibits insulin resistance, thereby preventing the activation of sterol regulatory element-binding proteins -1c and carbohydrate response element binding protein in hepatocytes through its PPAR-α agonistic action. SARO treatment reduces lipotoxicity-mediated oxidative stress by activating the nuclear factor erythroid 2-related factor 2 and transcriptionally expressing the antioxidants from the antioxidant response element in the nucleus through its PPAR-γ agonistic action. SARO provides a PPAR-α/γ-mediated anti-inflammatory effect by preventing the phosphorylation of mitogen-activated protein kinases (JNK and ERK) and nuclear factor kappa B in hepatocytes. Additionally, SARO interferes with transforming growth factor-β/Smad downstream signaling, thereby reducing liver fibrosis progression through its PPAR-α/γ agonistic actions. Thus, SARO improves insulin resistance and dyslipidemia in NAFLD, reduces lipid accumulation in the liver, and thereby prevents mitochondrial toxicity, oxidative stress, inflammation, and fibrosis progression. This review summarizes the possible molecular mechanism of SARO in the NAFLD.

Role of lifestyle and glucagon-like peptide-1 receptor agonists for weight loss in obesity, type 2 diabetes and steatotic liver diseases

BACKGROUND

The current obesity pandemic has given rise to associated comorbidities and complications, including type 2 diabetes and metabolic dysfunction-associated steatotic liver disease (MASLD). During the last decade, certain glucagon-like peptide 1 receptor agonists (GLP-1RA), originally developed as antihyperglycemic drugs, also demonstrated efficacy for weight loss.

AIMS

To review shared pathophysiologic features of common metabolic diseases and compare therapeutic strategies to reduce body weight and related complications.

METHODS

We performed an extensive literature research to describe the effects of lifestyle modification, first-generation anti-obesity drugs, and GLP-1RA on weight loss in humans with obesity, type 2 diabetes and MASLD.

RESULTS

Until recently, treatment of obesity has been limited to lifestyle modification, which offer moderate degree and sustainability of weight loss. The few approved first-generation anti-obesity drugs are either limited to short term use or to certain forms of obesity. Some GLP-1RA significantly decrease caloric intake and body weight. Liraglutide and semaglutide have therefore been approved for treating people with obesity. They also lead to a reduction of hepatic fat content and inflammation in people with biopsy-confirmed MASLD. Possible limitations comprise adverse effects, treatment adherence and persistence.

CONCLUSION

Certain GLP-1RA are superior to lifestyle modification and first-generation anti-obesity drugs in inducing weight loss. They have therefore markedly changed the portfolio of obesity treatment with additional beneficial effects on steatotic liver disease.

Milk thistle protects against non-alcoholic fatty liver disease induced by dietary thermally oxidized tallow

Non-alcoholic fatty liver disease (NAFLD) is a chronic condition caused by several factors including thermally oxidized tallow. Various strategies have been considered to ameliorate NAFLD. However, the role of milk thistle (MT) in ameliorating NAFLD caused by thermally oxidized tallow has not been reported. The purpose of this study was to evaluate the ability of milk thistle to protect rabbits from the toxicity of oxidized tallow (OT). The rabbits were given OT and an extract of MT. The composition of MT was analyzed using HPLC-DAD, and tallow samples were studied using GC-MS. The study also examined liver histology, antioxidant levels, liver-related inflammatory markers, and serum lipid profile. The results showed that the major components of the MT extract were silybin B, formononetin-glucuronic acid, proanthocyanidin B1, silychristin B, silydianin, and isosilybin A. The group given OT showed elevated lipid profiles, lower antioxidant status, higher levels of hepatic inflammatory markers, and lower levels of anti-inflammatory markers. This group also had higher fat storage in the liver compared to the control or treatment groups. However, when MT was supplemented, the pro-inflammatory cytokines (IL-1, IL-4, IL-6, and TNF-α) and antioxidant status (CAT, SOD, GSH-Px, GSH, and TBARS) of the liver returned to normal. This suggests that MT extract is an excellent source of hepatoprotective compounds. It protects the liver by increasing antioxidant enzymes, decreasing pro-inflammatory cytokines, and increasing anti-inflammatory markers.

Air pollution, life's essential 8, and risk of severe non-alcoholic fatty liver disease among individuals with type 2 diabetes

BACKGROUND

The impacts of long-term exposure to air pollution on the risk of subsequent non-alcoholic fatty liver disease (NAFLD) among participants with type 2 diabetes (T2D) is ambiguous. The modifying role of Life's Essential 8 (LE8) remains unknown.

METHODS

This study included 23,129 participants with T2D at baseline from the UK Biobank. Annual means of nitrogen dioxide (NO2), nitrogen oxides (NOX), and particulate matter (PM2.5, PM2.5-10, PM10) were estimated using the land-use regression model for each participant. The associations between exposure to air pollution and the risk of severe NAFLD were evaluated using Cox proportional hazard models. The effect modification of LE8 was assessed through stratified analyses.

RESULTS

During a median 13.6 years of follow-up, a total of 1,123 severe NAFLD cases occurred. After fully adjusting for potential covariates, higher levels of PM2.5 (hazard ratio [HR] = 1.12, 95%CI:1.02, 1.23 per interquartile range [IQR] increment), NO2 (HR = 1.15, 95%CI:1.04, 1.27), and NOX (HR = 1.08, 95%CI:1.01, 1.17) were associated with an elevated risk of severe NAFLD. In addition, LE8 score was negatively associated with the risk of NAFLD (HR = 0.97, 95% CI: 0.97, 0.98 per point increment). Compared with those who had low air pollution and high LE8, participants with a high air pollution exposure and low LE8 had a significantly higher risk of severe NAFLD.

CONCLUSIONS

Our findings suggest that long-term exposure to air pollution was associated with an elevated risk of severe NAFLD among participants with T2D. A lower LE8 may increase the adverse impacts of air pollution on NAFLD.

Steatotic Liver Disease: Pathophysiology and Emerging Pharmacotherapies

Steatotic liver disease (SLD) displays a dynamic and complex disease phenotype. Consequently, the metabolic dysfunction-associated steatotic liver disease (MASLD)/metabolic dysfunction-associated steatohepatitis (MASH) therapeutic pipeline is expanding rapidly and in multiple directions. In parallel, noninvasive tools for diagnosing and monitoring responses to therapeutic interventions are being studied, and clinically feasible findings are being explored as primary outcomes in interventional trials. The realization that distinct subgroups exist under the umbrella of SLD should guide more precise and personalized treatment recommendations and facilitate advancements in pharmacotherapeutics. This review summarizes recent updates of pathophysiology-based nomenclature and outlines both effective pharmacotherapeutics and those in the pipeline for MASLD/MASH, detailing their mode of action and the current status of phase 2 and 3 clinical trials. Of the extensive arsenal of pharmacotherapeutics in the MASLD/MASH pipeline, several have been rejected, whereas other, mainly monotherapy options, have shown only marginal benefits and are now being tested as part of combination therapies, yet others are still in development as monotherapies. Although the Food and Drug Administration (FDA) has recently approved resmetirom, additional therapeutic approaches in development will ideally target MASH and fibrosis while improving cardiometabolic risk factors. Due to the urgent need for the development of novel therapeutic strategies and the potential availability of safety and tolerability data, repurposing existing and approved drugs is an appealing option. Finally, it is essential to highlight that SLD and, by extension, MASLD should be recognized and approached as a systemic disease affecting multiple organs, with the vigorous implementation of interdisciplinary and coordinated action plans. SIGNIFICANCE STATEMENT: Steatotic liver disease (SLD), including metabolic dysfunction-associated steatotic liver disease and metabolic dysfunction-associated steatohepatitis, is the most prevalent chronic liver condition, affecting more than one-fourth of the global population. This review aims to provide the most recent information regarding SLD pathophysiology, diagnosis, and management according to the latest advancements in the guidelines and clinical trials. Collectively, it is hoped that the information provided furthers the understanding of the current state of SLD with direct clinical implications and stimulates research initiatives.

Vine tea total flavonoids activate the AMPK/mTOR pathway to amelioration hepatic steatosis in mice fed a high-fat diet

Vine tea (Ampelopsis grossedentata), a traditional Chinese tea, is rich in flavonoids with various biological activities. Our study found that Vine tea total flavonoids (TFs) treatment reduced the body mass and blood lipid levels and improved the hepatic tissue morphology in mice fed the high-fat diet (HFD). In vivo, TF treatment activated the hepatic adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway, initiated autophagy, and regulated the expression levels of proteins for lipid metabolism in those HFD-fed mice. In vitro, TF treatment dramatically reduced the lipid droplets and triacylglycerol content in HepG2 and L02 cells treated with oleic acid (OA). These were associated with the activation of the AMPK/mTOR pathway and autophagy initiation in OA-treated hepatocytes. This phenotype was abolished in the presence of 3-methyladenine, an autophagy inhibitor. Our results indicated that the TF activation of AMPK/mTOR leads to the stimulation of autophagy and a decrease in the buildup of intracellular lipids in hepatocytes, showing the potential of TF as a therapeutic agent for nonalcoholic fatty liver disease. PRACTICAL APPLICATION: Vine tea, a tea drink, has been consumed by Chinese folk for over a thousand years. The result of this study will provide evidence that vine tea total flavonoids have potential use as a functional material for the prevention and amelioration of nonalcoholic fatty liver disease.

Elucidating cuproptosis in metabolic dysfunction-associated steatotic liver disease

Emerging research into metabolic dysfunction-associated steatotic liver disease (MASLD) up until January 2024 has highlighted the critical role of cuproptosis, a unique cell death mechanism triggered by copper overload, in the disease's development. This connection offers new insights into MASLD's complex pathogenesis, pointing to copper accumulation as a key factor that disrupts lipid metabolism and insulin sensitivity. The identification of cuproptosis as a significant contributor to MASLD underscores the potential for targeting copper-mediated pathways for novel therapeutic approaches. This promising avenue suggests that managing copper levels could mitigate MASLD progression, offering a fresh perspective on treatment strategies. Further investigations into how cuproptosis influences MASLD are essential for unraveling the detailed mechanisms at play and for identifying effective interventions. The focus on copper's role in liver health opens up the possibility of developing targeted therapies that address the underlying causes of MASLD, moving beyond symptomatic treatment to tackle the root of the problem. The exploration of cuproptosis in the context of MASLD exemplifies the importance of understanding metal homeostasis in metabolic diseases and represents a significant step forward in the quest for more effective treatments. This research direction lights path for innovative MASLD management and reversal.

Changes in the terminology and diagnostic criteria of non-alcoholic fatty liver disease: Implications and opportunities

Fatty liver disease (FLD) is a highly prevalent pathological liver disorder. It has many and varied etiologies and has heterogeneous clinical course and outcome. Its proper nomenclature and classification have been problematic since its initial recognition. Traditionally, it was divided into two main categories: Alcohol-associated liver disease and nonalcoholic FLD (NAFLD). Among these, the latter condition has been plagued with nomenclature and classification issues. The two main objections to its use have been the use of negative (non-alcoholic) and stigmatizing (fatty) terms in its nomenclature. Numerous attempts were made to address these issues but none achieved universal acceptance. Just recently, NAFLD has received a new nomenclature from an international collaborative effort based on a rigorous scientific methodology. FLD has been renamed steatotic liver disease (SLD), and NAFLD as metabolic dysfunction-associated SLD. Metabolic dysfunction-associated steatohepatitis was chosen as the replacement terminology for non-alcoholic steatohepatitis. This is a significant positive change in the nomenclature and categorization of FLD and will likely have a major impact on research, diagnosis, treatment, and prognosis of the disease in the future.

Ip3r-Grp75-Vdac and Relevant Ca2+ Signaling Regulate Dietary Palmitic Acid-Induced De Novo Lipogenesis by Mitochondria-Associated ER Membrane (MAM) Recruiting Seipin in Yellow Catfish

BACKGROUND

The mitochondria-associated endoplasmic reticulum membrane (MAM) is the central hub for endoplasmic reticulum and mitochondria functional communication. It plays a crucial role in hepatic lipid homeostasis. However, even though MAM has been acknowledged to be rich in enzymes that contribute to lipid biosynthesis, no study has yet investigated the exact role of MAM on hepatic neutral lipid synthesis.

OBJECTIVES

To address these gaps, this study investigated the systemic control mechanisms of MAM on neutral lipids synthesis by recruiting seipin, focusing on the role of the inositol trisphosphate receptor-1,4,5(Ip3r)-75 kDa glucose-regulated protein (Grp75)-voltage-dependent anion channel (Vdac) complex and their relevant Ca2+ signaling in this process.

METHODS

To this end, a model animal for lipid metabolism, yellow catfish (Pelteobagrus fulvidraco), were fed 6 different diets containing a range of palmitic acid (PA) concentrations from 0-150 g/kg in vivo for 10 wk. In vitro, experiments were also conducted to intercept the MAM-mediated Ca2+ signaling in isolated hepatocytes by transfecting them with si-mitochondrial calcium uniporter (mcu). Because mcu was placed in the inner mitochondrial membrane (IMM), si-mcu cannot disrupt MAM's structural integrity.

RESULTS

1. Hepatocellular MAM subproteome analysis indicated excessive dietary PA intake enhanced hepatic MAM structure joined by activating Ip3r-Grp75-Vdac complexes. 2. Dietary PA intake induced hepatic neutral lipid accumulation through MAM recruiting Seipin, which activated lipid droplet biogenesis. Our findings also revealed a previously unidentified mechanism whereby MAM-recruited seipin and controlled hepatic lipid homeostasis, depending on Ip3r-Grp75-Vdac-controlled Ca2+ signaling and not only MAM's structural integrity.

CONCLUSIONS

These results offer a novel insight into the MAM-recruited seipin in controlling hepatic lipid synthesis in a MAM structural integrity-dependent and Ca2+ signaling-dependent manner, highlighting the critical contribution of MAM in maintaining hepatic neutral lipid homeostasis.

Adherence to an antioxidant diet and lifestyle is associated with reduced risk of cardiovascular disease and mortality among adults with nonalcoholic fatty liver disease: evidence from NHANES 1999-2018

Background

Nonalcoholic fatty liver disease (NAFLD) stands a prevalent chronic liver condition significantly influenced by oxidative stress. We investigated the unclear relationship between antioxidant-rich diet and lifestyle and cardiovascular disease (CVD) prevalence rate and mortality in adult patients with NAFLD.

Methods

This study utilized data from the National Health and Nutrition Examination Survey (NHAENS) spanning from 1999 to 2018 to investigate the association between adherence to an antioxidant-rich diet and lifestyle and the cardiovascular disease (CVD) prevalence rate and mortality in adult patients with NAFLD. The study employed the Oxidative Balance Score (OBS) to define antioxidant diet and lifestyle.

Results

Including 8,670 adult patients with NAFLD, the study revealed an inverse association between OBS and the prevalence of most CVD conditions. Fully adjusted models demonstrated that each unit increase in diet OBS, lifestyle OBS, and overall OBS corresponded to a 2, 7, and 2% reduction in all-cause mortality, respectively. In models 2, findings revealed that lifestyle Q2 and Q3 were linked to reduced cancer mortality, whereas diet and overall OBS did not exhibit an association. Additionally, Stratified analysis revealed that age (<45 years) and education level (> high school) significantly influenced the association between the OBS and the prevalence of CVD.

Conclusion

These results underscore the protective link between adherence to an antioxidant diet and lifestyle and a diminished prevalence of CVD and mortality in adults with NAFLD, particularly among younger and higher-educated populations.