Mitochondria, oxidative stress and nonalcoholic fatty liver disease: A complex relationship

Highly sensitive near-infrared fluorescent probe for monitoring peroxynitrite in nonalcoholic fatty liver disease: Toward early diagnosis and therapeutic evaluation

Nonalcoholic fatty liver disease (NAFLD) poses a significant global health concern, necessitating precise diagnostic tools and effective treatment strategies. Peroxynitrite (ONOO-), a reactive oxygen species, plays a pivotal role in NAFLD pathogenesis, highlighting its potential as a biomarker for disease diagnosis and therapeutic evaluation. This study reports on the development of a near-infrared (NIR) fluorescent probe, designated DRP-O, for the selective detection of ONOO- with high sensitivity and photostability. DRP-O exhibits rapid response kinetics (within 2 min) and an impressive detection limit of 2.3 nM, enabling real-time monitoring of ONOO- dynamics in living cells. Notably, DRP-O demonstrates excellent photostability under continuous laser irradiation, ensuring reliable long-term monitoring in complex biological systems. We apply DRP-O to visualize endogenous ONOO- in living cells, demonstrating its potential for diagnosing and monitoring NAFLD-related oxidative stress. Furthermore, DRP-O effectively evaluates the efficacy of therapeutic drugs in NAFLD cell models, underscoring its potential utility in drug screening studies. Moreover, we confirm DRP-O to enable selective identification of fatty liver tissues in a mouse model of NAFLD, indicating its potential for the early diagnosis of NAFLD. Collectively, DRP-O represents a valuable tool for studying ONOO- dynamics, evaluating drug efficacy, and diagnosing NAFLD, offering insights into novel therapeutic strategies for this prevalent liver disorder.

Melatonin prevents glyphosate-induced hepatic lipid accumulation in roosters via activating Nrf2 pathway

BACKGROUND

Glyphosate (GLY) is a widely used herbicide with well-defined hepatotoxic effects, in which oxidative stress has been shown to be involved in the pathogenesis of hepatotoxicity. Melatonin (MET), an effective free radical scavenger, has been revealed to alleviate drug-induced liver damage by inhibiting oxidative stress.

METHODS

In this study, a rooster model with primary chicken embryo hepatocytes was applied to elucidate the therapeutic effects of MET against GLY-induced hepatic damage and the potential mechanism. Histopathological examinations, biochemical tests and immunoblotting analysis were used to monitor the protective effects of MET on GLY-induced hepatic lipid accumulation. Molecular docking analysis was used to reveal the key reason of MET-improved hepatic lipid deposition.

RESULTS

Data firstly showed that MET administration markedly improved GLY-induced hepatic injury, as evidenced by normalized liver enzymes and alleviated pathological changes of liver tissues. Moreover, MET supplementation alleviated GLY-induced hepatic lipid accumulation, which was correlated with improved serum and hepatic lipid profiles and normalized expression of lipolysis- and lipogenesis-related proteins. Notably, MET significantly inhibited vital enzymes involved in stimulating oxidative stress. Moreover, MET enhanced GLY-inhibited Nrf2 nuclear transcription and increased the expressions of its downstream target genes HO1 and NQO1. Further studies revealed that MET may interact with Nrf2 to enhance nuclear translocation of Nrf2.

CONCLUSION

Collectively, our results provide the first direct evidence that MET is a novel regulator of Nrf2, highlighting that Nrf2 may be a potential therapeutic target for GLY-induced lipotoxic liver injury.

Lycorine ameliorates liver steatosis, oxidative stress, ferroptosis and intestinal homeostasis imbalance in MASLD mice

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common liver disease worldwide and few drugs are available for its treatment. Lycorine has effective anti-inflammatory and lipid-lowering effects, but the impact on MASLD is not fully understood. In this study, we intend to test the intervention effect of lycorine on MASLD.

METHODS

A MASLD mouse model was constructed on a high-fat diet for 16 weeks, and low, medium, and high doses of lycorine were given by gavage for the last 4 weeks. Detecting indicators related to liver steatosis, oxidative stress, and ferroptosis. In vivo and in vitro experiments co-validate potential targets identified by network pharmacology, molecular docking and western blot for lycorine intervention in MASLD liver. A combination of pathology, western blot, qRT-PCR, and 16 S rRNA sequencing verified adipose tissue and intestinal alterations.

RESULTS

Lycorine ameliorated hepatic steatosis, oxidative stress and ferroptosis in MASLD mice by inhibiting the expression of phosphorylated EGFR, inhibiting the PI3K/AKT signaling pathway. We also observed a dose-dependent effect of lycorine to improve some of the indicators of MASLD. In vitro, knockdown of EGFR significantly attenuated palmitic acid-induced hepatocyte steatosis. In addition, lycorine promoted WAT browning for thermogenesis and energy consumption, affected the composition of intestinal flora, improved the intestinal barrier, and reduced intestinal inflammation.

CONCLUSIONS

EGFR was the target of lycorine intervention in MASLD. Lycorine ameliorated hepatic steatosis, oxidative stress and ferroptosis by affecting the EGFR/PI3K/AKT signaling pathway in MASLD mice. Furthermore, lycorine promoted WAT browning and ameliorated intestinal homeostatic imbalance. The above effects may also have dose-dependent effects.

A Review on the Protecting Effects and Molecular Mechanisms of Berries Against a Silent Public Health Concern: Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) poses a silent threat to human health, with prevalence rising at an alarming rate. The treatment and prevention of NAFLD depend on novel approaches as no effective treatment options are currently available. Berries are unique sources of phenolic compounds that have proven roles in disease prevention and health promotion. However, a comprehensive review of the effects of different berries on NAFLD and related pathologies is lacking. Thus, the present review aims to summarize the effects of berry extracts, plant parts, and bioactive compounds from twenty-one different berries on NAFLD. The molecular mechanisms involved include the regulation of lipid homeostasis, modulation of oxidative stress and inflammation markers, and activation of different signaling pathways in different in vitro and in vivo NAFLD models. Furthermore, their modulatory effects on the gut microbiota have also been highlighted. Clinical intervention research on the benefits of berries in NAFLD is limited; nonetheless, this paper discusses clinical studies demonstrating the effects of different berries in people with NAFLD. Future research should focus on long-term clinical studies to compare the therapeutic potentials of different berries against NAFLD.

Application and mechanism of Chinese herb medicine in the treatment of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver condition closely associated with metabolic syndrome, with its incidence rate continuously rising globally. Recent studies have shown that the development of NAFLD is associated with insulin resistance, lipid metabolism disorder, oxidative stress and endoplasmic reticulum stress. Therapeutic strategies for NAFLD include lifestyle modifications, pharmacological treatments, and emerging biological therapies; however, there is currently no specific drug to treat NAFLD. However Chinese herb medicine (CHM) has shown potential in the treatment of NAFLD due to its unique therapeutic concepts and methods for centuries in China. This review aims to summarize the pathogenesis of NAFLD and some CHMs that have been shown to have therapeutic effects on NAFLD, thus enriching the scientific connotation of TCM theories and facilitating the exploration of TCM in the treatment of NAFLD.

Elevated serum growth differentiation factor 15 and decorin predict the fibrotic progression of metabolic dysfunction-associated steatotic liver disease

Mitochondrial dysfunction with oxidative stress contributes to metabolic dysfunction-associated steatotic liver disease (MASLD) progression. We aimed to evaluate the fibrosis predictive efficacy of a novel non-invasive diagnostic panel using metabolic stress biomarkers. From a population-based general cohort, 144 subjects with MASLD were recruited in the development group and underwent magnetic resonance imaging-based liver examinations, anthropometric and laboratory tests. As an external validation group, 41 patients enrolled in a biopsy-evaluated MASLD cohort participated in this study. Liver fat content and stiffness were measured by magnetic resonance (MR) imaging-proton density fat fraction and MR elastography (MRE), respectively. Serologic stress biomarkers were quantitated by ELISA. Multivariate regression showed that waist-to-height ratio, growth differentiation factor-15 (GDF15), γ-glutamyltransferase, decorin, and alkaline-phosphatase were independent predictors of hepatic fibrosis (rank-ordered by Wald). The area under receiver-operator characteristics curve [AUROC (95% CI)) of the metabolic stress index for fibrosis (MSI-F) was 0.912 (0.85‒0.98) and 0.977 (0.92‒1.00) in development and validation groups, respectively. MSI-F also had better diagnostic accuracy (82.6‒92.4%) than other fibrosis indices in the both study cohorts. MSI-F consistently differentiated fibrosis severities across cohorts of MRE-evaluated general population and biopsy-proven patients with MASLD, while other indices showed no or less discrimination. MSI-F, as a novel non-invasive index based on a stress-stimulated protective hormone GDF15 and decorin, effectively predicted hepatic fibrosis. Furthermore, MSI-F may serve as pre-screening tool to increase the population that could be excluded from further evaluation, reducing unnecessary invasive investigations more effectively than other indices.

A systematic review of dietary and circulating carotenoids and liver disease

Background: due to the high incidence of liver disease and the severity of adverse outcomes, liver disease has become a serious public health problem, bringing a huge disease burden to individuals, families, and society. Most studies have shown significant differences in serum carotenoid content and dietary carotenoid intake between liver disease patients and non-liver disease patients, but some studies have reported contrary results. This paper aimed to systematically review and analyze all published epidemiological studies on carotenoids and liver disease to quantitatively assess the relationship between serum and dietary carotenoid concentrations and liver disease. Methods: by systematically searching PubMed, Web of Science, Scopus, Embase, and Cochrane databases according to pre-combined search terms from inception to July 23, 2024, 30 studies were found to meet the exclusion criteria. Finally, 3 RCT studies, 6 cohort studies, 11 case-control studies, 9 cross-sectional studies, and 1 RCT-combined cross-sectional study were included in the further analysis. Two reviewers independently scored the literature quality and extracted data, and the results were represented by the standard mean difference (SMD) with a 95% confidence interval. Cochran Q statistics and I2 statistics were used to evaluate statistical heterogeneity (defined as significant when P < 0.05 or I2 > 50%). When there was insignificant heterogeneity, a fixed effects model was selected; otherwise a random effects model was used. Publication bias was assessed by the Egger test. Results: pooled meta-analysis showed that serum α-carotene (SMD = -0.58, 95% CI (-0.83, -0.32), P < 0.001), β-carotene (SMD = -0.81, 95% CI (-1.13, -0.49), P < 0.001), and lycopene (SMD = -1.06, 95% CI (-1.74, -0.38), P < 0.001) were negatively correlated with the risk and severity of liver disease. However, no significant difference was observed between serum β-cryptoxanthin (SMD = 0.02, 95% CI (-0.41, 0.45), P = 0.92) and lutein/zeaxanthin (SMD = 0.62, 95% CI (-1.20, 2.45), P = 0.502). Dietary β-carotene intake (SMD = -0.22, 95% CI (-0.31, -0.13), P < 0.001) was negatively associated with the risk of liver disease. The Egger test showed no publication bias (P > 0.05). An intake of more than 6 mg of carotenoids on an energy-restricted diet can effectively alleviate the symptoms of NAFLD. Conclusion: lower serum concentrations of α-carotene, β-carotene, and lycopene were associated with a higher risk of liver disease. Meanwhile, dietary intake of β-carotene could reduce the incidence of liver disease. However, for malignant diseases such as liver cancer, it did not show the significant effects of carotenoid supplementation.

GTPBP8 mitigates nonalcoholic steatohepatitis (NASH) by depressing hepatic oxidative stress and mitochondrial dysfunction via PGC-1α signaling

Nonalcoholic steatohepatitis (NASH) is emerging as a major cause of liver transplantation and hepatocellular carcinoma (HCC). Regrettably, its pathological mechanisms are still not fully comprehended. GTP-binding protein 8 (GTPBP8), belonging to the GTP-binding protein superfamily, assumes a crucial role in RNA metabolism, cell proliferation, differentiation, and signal transduction. Its aberrant expression is associated with oxidative stress and mitochondrial dysfunctions. Nevertheless, its specific functions and mechanisms of action, particularly in NASH, remain elusive. In our current study, we initially discovered that human hepatocytes L02 displayed evident mitochondrial respiratory anomaly, mitochondrial damage, and dysfunction upon treatment with palmitic acids and oleic acids (PO), accompanied by significantly reduced GTPBP8 expression levels through RNA-Seq, RT-qPCR, western blotting, and immunofluorescence assays. We then demonstrated that GTPBP8 overexpression mediated by adenovirus vector (Ad-GTPBP8) markedly attenuate lipid accumulation, inflammatory response, and mitochondrial impair and dysfunction in hepatocytes stimulated by PO. Conversely, adenovirus vector-mediated GTPBP8 knockdown (Ad-shGTPBP8) significantly accelerated lipid deposition, inflammation and mitochondrial damage in PO-treated hepatocytes in vitro. Furthermore, we constructed an in vivo NASH murine model by giving a 16-week high fat high cholesterol diet (HFHC) diet to hepatocyte specific GTPBP8-knockout (GTPBP8HKO) mice. We firstly found that HFHC feeding led to metabolic disorder in mice, including high body weight, blood glucose and insulin levels, and liver dysfunctions, which were accelerated in these NASH mice with GTPBP8 deficiency in hepatocytes. Consistently, GTPBP8HKO remarkably exacerbated the progression of NASH phenotypes induced by HFHC, as proved by the anabatic lipid accumulation, inflammation, fibrosis and reactive oxygen species (ROS) production in liver tissues, which could be largely attributed to the severe mitochondrial damage and dysfunction. Mechanistically, we further identified that GTPBP8 interacted with peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in hepatocytes. Importantly, the hepaprotective effects of GTPBP8 against mitochondrial dysfunction, oxidative stress and inflammation was largely dependent on PGC-1α expression. Collectively, GTPBP8 may exert a protective role in the progression of NASH, and targeting the GTPBP8/PGC-1α axis may represent a potential strategy for NASH treatment by improving mitochondrial functions.

A new perspective on liver diseases: Focusing on the mitochondria-associated endoplasmic reticulum membranes

The pathogenesis of liver diseases is multifaceted and intricate, posing a persistent global public health challenge with limited therapeutic options. Therefore, further research into liver diseases is imperative for better comprehension and advancement in treatment strategies. Numerous studies have confirmed the endoplasmic reticulum (ER) and mitochondria as key organelles driving liver diseases. Notably, the mitochondrial-associated ER membranes (MAMs) establish a physical and functional connection between the ER and mitochondria, highlighting the importance of inter-organelle communication in maintaining their functional homeostasis. This review delves into the intricate architecture and regulative mechanism of the integrated MAM that facilitate the physiological transfer of signals and substances between organelles. Additionally, we also provide a detailed overview regarding the varied pathogenic roles of malfunctioning MAM in liver diseases, focusing on its involvement in the progression of ER stress and mitochondrial dysfunction, the regulation of mitochondrial dynamics and Ca2+ transfer, as well as the disruption of lipid and glucose homeostasis. Furthermore, the current challenges and prospects associated with MAM in liver disease research are thoroughly discussed. In conclusion, elucidating the specific structure and function of MAM in different liver diseases may pave the way for novel therapeutic strategies.

New insights into the role of mitochondrial dynamics in oxidative stress-induced diseases

The accumulation of excess reactive oxygen species (ROS) can lead to oxidative stress (OS), which can induce gene mutations, protein denaturation, and lipid peroxidation directly or indirectly. The expression is reduced ATP level in cells, increased cytoplasmic Ca2+, inflammation, and so on. Consequently, ROS are recognized as significant risk factors for human aging and various diseases, including diabetes, cardiovascular diseases, and neurodegenerative diseases. Mitochondria are involved in the production of ROS through the respiratory chain. Abnormal mitochondrial characteristics, including mitochondrial OS, mitochondrial fission, mitochondrial fusion, and mitophagy, play an important role in various tissues. However, previous excellent reviews focused on OS-induced diseases. In this review, we focus on the latest progress of OS-induced mitochondrial dynamics, discuss OS-induced mitochondrial damage-related diseases, and summarize the OS-induced mitochondrial dynamics-related signaling pathways. Additionally, it elaborates on potential therapeutic methods aimed at preventing oxidative stress from further exacerbating mitochondrial disorders.

Mettl3-m6A-YTHDF1 axis promotion of mitochondrial dysfunction in metabolic dysfunction-associated steatotic liver disease

BACKGROUND

N6-methyladenosine (m6A) mRNA modification and mitochondrial function hold paramount importance in the advancement of metabolic dysfunction-associated steatotic liver disease (MASLD).

AIM

The aim of this study was to elucidate the impact of m6A on hepatic mitochondrial dysfunction and provide a novel perspective for a more comprehensive understanding of the pathogenesis of MASLD.

METHODS

High-throughput screening methods were used to identify the underlying transcriptome and proteome changes in MASLD model mice. Western blotting, blue native gel electrophoresis (BNGE), dot blot, and Seahorse analyses were conducted to identify and validate the underlying regulatory mechanisms of m6A on mitochondria.

RESULTS

In vivo, abnormal m6A modification in MASLD was attributed to the upregulation of methyltransferase like 3 (Mettl3) and the downregulation of YTH N6-methyladenosine RNA binding protein 1 (YTHDF1) induced by high-fat foods. In vitro, knockdown of Mettl3 inhibited hepatic oxidative phosphorylation (OXPHOS) and the mitochondrial respiratory chain (MRC), while overexpression of Mettl3 promoted these processes. However, knockout of the reader protein YTHDF1, which plays a crucial role in the m6A modification process, counteracted the effect of Mettl3 and suppressed mitochondrial OXPHOS.

CONCLUSIONS

In MASLD, damage to the MRC may be regulated by the Mettl3-m6A-YTHDF1 axis, particularly by the role of YTHDF1. Modulation of the Mettl3-m6A-YTHDF1 axis has the potential to improve mitochondrial function, alleviate MASLD symptoms, and decrease the likelihood of disease progression.

Disturbance in communication between mitochondrial redox processes and the AMPK/PGC-1α/SIRT-1 axis influences diverse organ symptoms in lupus-affected mice

BACKGROUND

Mechanisms behind multiple organ involvement in lupus, is still an enigma for researchers. Mitochondrial dysfunction and oxidative stress are known to be important aspects in lupus etiology however, their role in lupus organ manifestation is yet to be understood. The present study is based on the understanding of interplay between AMPK/PGC-1α/SIRT-1 axis, mitochondrial complexes, and anti-oxidants levels, which might be involved in lupus organ pathology.

METHODOLOGY

Pristane-induced Balb/c mice lupus model (PIL) was utilised and evaluation of anti-oxidants, mitochondrial complexes, pro-inflammatory cytokines levels, biochemical parameters were performed by standard procedures. Tissues were studied by haematoxylin and eosin staining followed by immunohistochemistry. The AMPK/PGC-1α/SIRT-1 expression was analysed by using qPCR and flowcytometry. Analysis of reactive oxygen species (ROS) among WBCs was performed by using various dyes (DCFDA, Mitosox, JC-1) on flowcytometry.

RESULT

Significant presence of immune complexes (Tissue sections), ANA (Serum), and pro-inflammatory cytokines (plasma), diminished anti-oxidants and altered biochemical parameters depict the altered pathology in PIL which was accompanied by dysregulated mitochondrial complex activity. Differential expression of the AMPK/PGC-1α/SIRT-1 axis was detected in tissue and correlation with mitochondrial and antioxidant activity emerged as negative in PIL group while positive in controls. Close association was observed between ROS, mitochondrial membrane potential, and AMPK/PGC-1α/SIRT-1 axis in WBCs.

CONCLUSION

This study concludes that mitochondria play a dual role in lupus organ pathology, contributing to organ damage while also potentially protecting against damage through the regulation of interactions between antioxidants and the AMPK axis expression.

Altered Mitochondrial Function in MASLD: Key Features and Promising Therapeutic Approaches

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease (NAFLD), encompasses a range of liver conditions from steatosis to nonalcoholic steatohepatitis (NASH). Its prevalence, especially among patients with metabolic syndrome, highlights its growing global impact. The pathogenesis of MASLD involves metabolic dysregulation, inflammation, oxidative stress, genetic factors and, notably, mitochondrial dysfunction. Recent studies underscore the critical role of mitochondrial dysfunction in MASLD's progression. Therapeutically, enhancing mitochondrial function has gained interest, along with lifestyle changes and pharmacological interventions targeting mitochondrial processes. The FDA's approval of resmetirom for metabolic-associated steatohepatitis (MASH) with fibrosis marks a significant step. While resmetirom represents progress, further research is essential to understand MASLD-related mitochondrial dysfunction fully. Innovative strategies like gene editing and small-molecule modulators, alongside lifestyle interventions, can potentially improve MASLD treatment. Drug repurposing and new targets will advance MASLD therapy, addressing its increasing global burden. Therefore, this review aims to provide a better understanding of the role of mitochondrial dysfunction in MASLD and identify more effective preventive and treatment strategies.

Korean Red Ginseng Improves Oxidative Stress-Induced Hepatic Insulin Resistance via Enhancing Mitophagy

This study explored the potential of saponins from Korean Red Ginseng to target the PINK1/Parkin mitophagy pathway, aiming to enhance insulin sensitivity in hepatocytes-a key factor in metabolic disorders like metabolic dysfunction-associated steatotic liver disease (MASLD) and type 2 diabetes. Results from both in vitro and in vivo experiments showed increased expression of PINK1 and Parkin, activating mitophagy and reducing oxidative stress through reduction in mitochondrial and total reactive oxygen species. Additionally, improvements in insulin signaling were observed, including the upregulation of phosphorylated IRS and AKT, and downregulation of gluconeogenic enzymes, underscoring the saponins' efficacy in boosting insulin sensitivity. The findings highlighted Korean Red Ginseng-derived saponins as potential treatments for insulin resistance and related metabolic conditions.

Hydrogen-Rich Water (HRW) Reduces Fatty Acid-Induced Lipid Accumulation and Oxidative Stress Damage through Activating AMP-Activated Protein Kinase in HepG2 Cells

Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterized by excessive fat accumulation in the liver. Intracellular oxidative stress induced by lipid accumulation leads to various hepatocellular injuries including fibrosis. However, no effective method for mitigating MASLD without substantial side effects currently exists. Molecular hydrogen (H2) has garnered attention due to its efficiency in neutralizing harmful reactive oxygen species (ROS) and its ability to penetrate cell membranes. Some clinical evidence suggests that H2 may alleviate fatty liver disease, but the precise molecular mechanisms, particularly the regulation of lipid droplet (LD) metabolism, remain unclear. This study utilized an in vitro model of hepatocyte lipid accumulation induced by free fatty acids (FFAs) to replicate MASLD in HepG2 cells. The results demonstrated a significant increase in LD accumulation due to elevated FFA levels. However, the addition of hydrogen-rich water (HRW) effectively reduced LD accumulation. HRW decreased the diameter of LDs and reduced lipid peroxidation and FFA-induced oxidative stress by activating the AMPK/Nrf2/HO-1 pathway. Overall, our findings suggest that HRW has potential as an adjunctive supplement in managing fatty liver disease by reducing LD accumulation and enhancing antioxidant pathways, presenting a novel strategy for impeding MASLD progression.

Chronic unpredictable mild stress increases serum aldosterone without affecting corticosterone levels and induces hepatic steatosis and renal injury in young adult male rats

Stress is often associated with anxiety and depressive symptoms in adolescents. Stress is associated with components of metabolic syndrome and inflammation. The present study hypothesizes that aldosterone, more than corticosterone, promotes chronic stress-hepatic steatosis and fibrosis, as well as renal inflammation and fibrosis in young adult rats. Thirty-two young adult male Wistar rats of 51 days old were divided into four groups (n = 8 per group): Control (C), chronic unpredictable mild stress (CUMS), control plus vehicle (C plus veh), CUMS plus eplerenone, a selective aldosterone blocker (CUMS plus EP). On postnatal day 51, eplerenone was administered orally through a gastric tube two hours before the start of the stress test. The CUMS paradigm was administered once daily at different times, with no repetition of the stressor sequence for four weeks. Renal inflammation and fibrosis were measured, as well as liver glycogen, triacylglycerol, and fibrosis levels. The serum concentrations of corticosterone, aldosterone, sodium, and creatinine were measured in urine and serum. The CUMS group showed a high level of serum aldosterone without affecting the level of corticosterone, increased urinary sodium, tubular atrophy, glomerular sclerosis, the presence of inflammation, and fibrosis, without affecting creatinine, increased glycogen content, triacylglycerol, and moderate fibrosis in the liver, and treatment with eplerenone prevented the inflammation, fibrosis, glycogen, and triacylglycerol. Our results show that chronic stress-induced aldosterone promotes hepatic steatosis and renal injury more than corticosterone. The prevention by eplerenone supports our hypothesis.

Machine learning-based algorithm identifies key mitochondria-related genes in non-alcoholic steatohepatitis

BACKGROUND

Evidence suggests that hepatocyte mitochondrial dysfunction leads to abnormal lipid metabolism, redox imbalance, and programmed cell death, driving the onset and progression of non-alcoholic steatohepatitis (NASH). Identifying hub mitochondrial genes linked to NASH may unveil potential therapeutic targets.

METHODS

Mitochondrial hub genes implicated in NASH were identified via analysis using 134 algorithms.

RESULTS

The Random Forest algorithm (RF), the most effective among the 134 algorithms, identified three genes: Aldo-keto reductase family 1 member B10 (AKR1B10), thymidylate synthase (TYMS), and triggering receptor expressed in myeloid cell 2 (TREM2). They were upregulated and positively associated with genes promoting inflammation, genes involved in lipid synthesis, fibrosis, and nonalcoholic steatohepatitis activity scores in patients with NASH. Moreover, using these three genes, patients with NASH were accurately categorized into cluster 1, exhibiting heightened disease severity, and cluster 2, distinguished by milder disease activity.

CONCLUSION

These three genes are pivotal mitochondrial genes implicated in NASH progression.

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.

Combination of two-photon fluorescent probes for carboxylesterase and ONOO- to visualize the transformation of nonalcoholic fatty liver to nonalcoholic steatohepatitis in liver orthotopic imaging

As the most common cause of liver diseases, nonalcoholic fatty liver disease (NAFLD) can be classified into nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH). While NAFL is generally benign, the transition from NAFL to NASH is a cardinal feature of the non-benign liver disease that leads to cirrhosis and cancer, which indicates that tracking the transformation of NAFL to NASH timely is significant for precision management of liver diseases. Therefore, two fluorescent probes (CNFCl and DRNO) have been developed to visualize this pathological event. α-Fluorochloroacetamide and α-ketoamide was employed as the recognition site for carboxylesterase (CE) in CNFCl and peroxynitrite (ONOO-) in DRNO, respectively. CNFCl (λem = 445 nm) and DRNO (λem = 560 nm) showed high specificity and sensitivity towards CE and ONOO- respectively. By incubating with CE/ONOO- for 0.5 h respectively, both the emission intensity of CNFCl (linear range: 0-0.2 U/mL) and DRNO (linear range: 0-17.5 μM) displayed significant enhancement. As a result, the detection limit of CNFCl and DRNO for CE and ONOO- was calculated as 4.2 mU/L and 0.05 μM respectively. More importantly, the emission spectra of CNFCl and DRNO in the presence of CE and ONOO- respectively were cross-talk free under the two-photon excitation of 720 nm. This greatly facilitated the simultaneous detection of CE and ONOO- at distinctive channel, thus ensuring the high fidelity of the detection. These two probes were combined to image the fluctuation of CE and ONOO- during the conversion of NAFL to NASH in vitro and in vivo. It was found that while CE displayed a tendency to rise and then reduce during the transition from NAFL to NASH, ONOO- increased continuously, confirming that the combined imaging by CNFCl and DRNO might visualize the transformation of NAFL to NASH. The results provide robust visual tool to decipher the relationship between the stage of NAFLD and the level of CE/ONOO-. We anticipate this study may open new avenues to distinguish NASH from NAFL, which may further promote the study of intracellular biological activities of CE and the development of NAFLD diagnostic methods.

Association between metabolic dysfunction-associated fatty liver disease and abdominal aortic aneurysm

BACKGROUND AND AIMS

Abdominal aortic aneurysm (AAA) is the second most common aortic pathological manifestation. Metabolic dysfunction-associated fatty liver disease (MAFLD) has a wide impact on the cardiovascular system and may be a risk factor for AAA. The aim of this study was to investigate whether MAFLD is associated with the risk of AAA.

METHODS AND RESULTS

We used data from the prospective UK Biobank cohort study. MAFLD is defined as hepatic steatosis plus metabolic abnormality, type 2 diabetes, or overweight/obesity. AAA is collected by ICD-10 code. Cox regression was established to analyze the association between MAFLD and AAA. A total of 370203 participants were included; the average age of the participants was 56.7 ± 8.0 years, and 134649 (36.4 %) were diagnosed with MAFLD. During the 12.5 years of follow-up, 1561 (0.4 %) participants developed AAA. After fully adjusting for confounding factors, individuals with MAFLD had a significantly increased risk of AAA (HR 1.521, 95 % CI 1.351-1.712, p < 0.001). Importantly, the risk of AAA increases with the severity of MAFLD as assessed by fibrosis scores. These associations were consistent according to sex, weight, and alcohol consumption but weaker in elderly or diabetics (P for interaction <0.05). The association between the MAFLD phenotype and AAA was independent of the polygenic risk score. Additionally, MAFLD was not associated with thoracic aortic aneurysm or aortic dissection events.

CONCLUSIONS

There was a significant relationship between MAFLD and AAA. These findings strongly recommend early prevention of AAA by intervening in MAFLD.

Inequities in primary liver cancer in Europe: The state of play

Given the increasing burden of liver cancer in Europe, it is crucial to investigate how social determinants of health (SDoH) affect liver cancer risk factors and access to care in order to improve health outcomes equitably. This paper summarises the available evidence on the differential distribution of liver cancer risk factors, incidence, and health outcomes in the European Economic Area and the United Kingdom from an SDoH perspective. Vulnerable and marginalised populations have low socio-economic and educational levels and are the most affected by liver cancer risk factors. Reasons for this include varied access to hepatitis B virus vaccination and limited access to viral hepatitis B and C screening, harm reduction, and treatment. Additionally, alcohol-related liver disease remains highly prevalent among individuals with low education, insecure employment, economic instability, migrants, and deprived populations. Moreover, significant variation exists across Europe in the proportion of adults with steatotic liver disease, overweight/obesity, and diabetes, based on geographical area, gender, socio-economic and educational background, and density of ultra-processed food outlets. Inequities in cirrhosis mortality rates have been reported, with the highest death rates among individuals living in socio-economically disadvantaged areas and those with lower educational levels. Furthermore, insufficient healthcare access for key populations with primary liver cancer is influenced by complex healthcare systems, stigmatisation, discrimination, low education, language barriers, and fear of disclosure. These challenges contribute to inequities in liver cancer care pathways. Future studies are needed to explore the different SDoH-interlinked effects on liver cancer incidence and outcomes in European countries. The ultimate goal is to develop evidence-based multilevel public health interventions that reduce the SDoH impact in precipitating and perpetuating the disproportionate burden of liver cancer in specific populations.

Can mothers consume caffeine? The issue of early life exposure and metabolic changes in offspring

Caffeine is a substance with central and metabolic effects. Although it is recommended that its use be limited during pregnancy, many women continue to consume caffeine. Direct and indirect actions of caffeine in fetuses and newborns promote adaptive changes, according to the Developmental Origins of Health and Diseases (DOHaD) concept. In fact, epidemiological and experimental evidence reveals the impact of early caffeine exposure. Here, we reviewed these findings with an emphasis on experimental models with rodents. The similarity of human and rodent caffeine metabolism allows the comprehension of molecular mechanisms affected by prenatal caffeine exposure. Maternal caffeine intake affects the body weight and endocrine system of offspring at birth and has long-term effects on the endocrine system, liver function, glucose and lipid metabolism, the cardiac system, the reproductive system, and behavior. Interestingly, some of these effects are sex dependent. Thus, the dose of caffeine considered safe for pregnant women may not be adequate for the prenatal period.

Pyridostigmine attenuated high-fat-diet induced liver injury by the reduction of mitochondrial damage and oxidative stress via α7nAChR and M3AChR

Obesity is a major cause of nonalcohol fatty liver disease (NAFLD), which is characterized by hepatic fibrosis, lipotoxicity, inflammation, and apoptosis. Previous studies have shown that an imbalance in the autonomic nervous system is closely related to the pathogenesis of NAFLD. In this study, we investigated the effects of pyridostigmine (PYR), a cholinesterase (AChE) inhibitor, on HFD-induced liver injury and explored the potential mechanisms involving mitochondrial damage and oxidative stress. A murine model of HFD-induced obesity was established using the C57BL/6 mice, and PYR (3 mg/kg/d) or placebo was administered for 20 weeks. PYR reduced the body weight and liver weight of the HFD-fed mice. Additionally, the serum levels of IL-6, TNF-α, cholesterol, and triglyceride were significantly lower in the PYR-treated versus the untreated mice, corresponding to a decrease in hepatic fibrosis, lipid accumulation, and apoptosis in the former. Furthermore, the mitochondrial morphology improved significantly in the PYR-treated group. Consistently, PYR upregulated ATP production and the mRNA level of the mitochondrial dynamic factors OPA1, Drp1 and Fis1, and the mitochondrial unfolded protein response (UPRmt) factors LONP1 and HSP60. Moreover, PYR treatment activated the Keap1/Nrf2 pathway and upregulated HO-1 and NQO-1, which mitigated oxidative injury as indicated by decreased 8-OHDG, MDA and H2 O2 levels, and increased SOD activity. Finally, PYR elevated acetylcholine (ACh) levels by inhibiting AChE, and upregulated the α7nAChR and M3AChR proteins in the HFD-fed mice. PYR alleviated obesity-induced hepatic injury in mice by mitigating mitochondrial damage and oxidative stress via α7nAChR and M3AChR.

Oxidative stress in metabolic dysfunction-associated steatotic liver disease (MASLD): How does the animal model resemble human disease?

Despite decades of research, the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD) is still not completely understood. Based on the evidence from preclinical models, one of the factors proposed as a main driver of disease development is oxidative stress. This study aimed to search for the resemblance between the profiles of oxidative stress and antioxidant defense in the animal model of MASLD and the group of MASLD patients. C57BL/6J mice were fed with the Western diet for up to 24 weeks and served as the animal model of MASLD. The antioxidant profile of mice hepatic tissue was determined by liquid chromatography-MS3 spectrometry (LC-MS/MS). The human cohort consisted of 20 patients, who underwent bariatric surgery, and 6 controls. Based on histological analysis, 4 bariatric patients did not have liver steatosis and as such were also classified as controls. Total antioxidant activity was measured in sera and liver biopsy samples. The hepatic levels of antioxidant enzymes and oxidative damage were determined by Western Blot. The levels of antioxidant enzymes were significantly altered in the hepatic tissue of mice with MASLD. In contrast, there were no significant changes in the antioxidant profile of hepatic tissue of MASLD patients, except for the decreased level of carbonylated proteins. Decreased protein carbonylation together with significant correlations between the thioredoxin system and parameters describing metabolic health suggest alterations in the thiol-redox signaling. Altogether, these data show that even though the phenotype of mice closely resembles human MASLD, the animal-to-human translation of cellular and molecular processes such as oxidative stress may be more challenging.

Comparative role of acetaminophen, carbon tetrachloride and thioacetamide in development of fibrosis in rats

Background

Several hepatotoxicants such as acetaminophen, carbon tetrachloride, and thioacetamide are repeatedly used to develop hepatic fibrosis to mimic the histological and hemodynamic characteristics of human illness. It may be a good idea to establish a better model among these hepatotoxicants to develop hepatic fibrosis.

Aim

The present study evaluated comparative toxic effects of three model hepatotoxicants for experimental progression of fibrosis or cirrhosis.

Materials and methods

Acetaminophen (200 mg/kg), carbon tetrachloride (200 µl/kg) and thioacetamide (200 mg/kg) were administered orally, thrice in a week for 8 weeks in different groups. After 8 weeks of exposure, animals were euthanized, blood and tissues were collected for various hematological, serological, tissue biochemical analysis and histological observations for comparative assessment of toxic consequences.

Results

Significant deviation was noted in liver function tests, lipid peroxidation, glutathione, activities of superoxide dismutase, catalase, and GSH cycle enzymes; aniline hydroxylase, amidopyrine-N-demethylase, DNA fragmentation and level of hydroxyproline when compared with control group. Histology also depicted damage in liver histoarchitecture with exposure to acetaminophen, carbon tetrachloride and thioacetamide. Tukey's HSD post hoc test confirmed that thioacetamide produced severe toxic effects in comparison to carbon tetrachloride and acetaminophen.

Conclusion

In conclusion, toxic effects were noted in ascending order as acetaminophen.

Erchen decoction alleviates the progression of NAFLD by inhibiting lipid accumulation and iron overload through Caveolin-1 signaling

ETHNOPHARMACOLOGICAL RELEVANCE

A combination of 6 different Chinese herbs known as Erchen decoction (ECD) has been traditionally used to treat digestive tract diseases and found to have a protective effect against nonalcoholic fatty liver disease (NAFLD). Despite its efficacy in treating NAFLD, the precise molecular mechanism by which Erchen Decoction regulated iron ion metabolism to prevent disease progression remained poorly understood.

AIM OF STUDY

Our study attempted to confirm the specific mechanism of ECD in reducing lipid and iron in NAFLD from the perspective of regulating the expression of Caveolin-1 (Cav-1).

STUDY DESIGN

In our study, the protective effect of ECD was investigated in Palmitic Acid + Oleic Acid-induced hepatocyte NAFLD model and high-fat diet-induced mice NAFLD model. To investigate the impact of Erchen Decoction (ECD) on lipid metabolism and iron metabolism via mediating Cav-1 in vitro, Cav-1 knockdown cell lines were established using lentivirus-mediated transfection techniques.

MATERIALS AND METHODS

We constructed NAFLD model by feeding with high-fat diet for 12 weeks in vivo and Palmitic Acid + Oleic Acid treatment for 24 h in vitro. The regulation of Lipid and iron metabolism results by ECD were detected by serological diagnosis, immunofluorescent and immunohistochemical staining, and western blotting. The binding ability of 6 small molecules of ECD to Cav-1 was analyzed by molecular docking.

RESULTS

We demonstrated that ECD alleviated the progression of NAFLD by inhibiting lipid accumulation, nitrogen oxygen stress, and iron accumulation in vivo and in vitro experiments. Furthermore, ECD inhibited lipid and iron accumulation in liver by up-regulating the expression of Cav-1, which indicated that Cav-1 was an important target for ECD to exert its curative effect.

CONCLUSIONS

In summary, our study demonstrated that ECD alleviated the accumulation of lipid and iron in NAFLD through promoting the expression of Cav-1, and ECD might serve as a novel Cav-1 agonist to treat NAFLD.

Contributing roles of mitochondrial dysfunction and hepatocyte apoptosis in liver diseases through oxidative stress, post-translational modifications, inflammation, and intestinal barrier dysfunction

This review provides an update on recent findings from basic, translational, and clinical studies on the molecular mechanisms of mitochondrial dysfunction and apoptosis of hepatocytes in multiple liver diseases, including but not limited to alcohol-associated liver disease (ALD), metabolic dysfunction-associated steatotic liver disease (MASLD), and drug-induced liver injury (DILI). While the ethanol-inducible cytochrome P450-2E1 (CYP2E1) is mainly responsible for oxidizing binge alcohol via the microsomal ethanol oxidizing system, it is also responsible for metabolizing many xenobiotics, including pollutants, chemicals, drugs, and specific diets abundant in n-6 fatty acids, into toxic metabolites in many organs, including the liver, causing pathological insults through organelles such as mitochondria and endoplasmic reticula. Oxidative imbalances (oxidative stress) in mitochondria promote the covalent modifications of lipids, proteins, and nucleic acids through enzymatic and non-enzymatic mechanisms. Excessive changes stimulate various post-translational modifications (PTMs) of mitochondrial proteins, transcription factors, and histones. Increased PTMs of mitochondrial proteins inactivate many enzymes involved in the reduction of oxidative species, fatty acid metabolism, and mitophagy pathways, leading to mitochondrial dysfunction, energy depletion, and apoptosis. Unique from other organelles, mitochondria control many signaling cascades involved in bioenergetics (fat metabolism), inflammation, and apoptosis/necrosis of hepatocytes. When mitochondrial homeostasis is shifted, these pathways become altered or shut down, likely contributing to the death of hepatocytes with activation of inflammation and hepatic stellate cells, causing liver fibrosis and cirrhosis. This review will encapsulate how mitochondrial dysfunction contributes to hepatocyte apoptosis in several types of liver diseases in order to provide recommendations for targeted therapeutics.

Exercise intensity impacts the improvement of metabolic dysfunction-associated steatotic liver disease via variations of monoacylglycerol O-acyltransferase 1 expression

BACKGROUND

The involvement of monoacylglycerol O-acyltransferase 1 (MOGAT1) in the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD) has been recognized. While exercise is recommended for the improvement of obesity and MASLD, the impact of exercise intensity remains unclear. This study aimed to examine the influence of exercise intensity on MOGAT1 expression in high-fat diet (HFD)-induced obese mice with MASLD.

METHOD

Male C57BL/6 mice aged 6 weeks were subjected to either a regular or HFD with 60 % fat content for 8 weeks. The mice were categorized into 5 groups based on their diet and exercise intensity: normal diet group (ND), HFD group, low-intensity exercise with HFD group (HFD+LIE), moderate-intensity exercise with HFD group (HFD+MIE), and high-intensity exercise (HIE) with HFD group (HFD+HIE). The duration of running was adjusted to ensure uniform exercise load across groups (total distance = 900 m): HFD+LIE at 12 m/min for 75 min, HFD+MIE at 15 m/min for 60 min, and HFD+HIE at 18 m/min for 50 min.

RESULTS

Lipid droplet size and MASLD activity score were significantly lower in the HFD+HIE group compared to other exercise-intensity groups (p < 0.05). Among the 3 intensity exercise groups, the lowest MOGAT1 protein expression was found in the HFD+HIE group (p < 0.05).

CONCLUSION

This study reveals that high-intensity exercise has the potential to mitigate MASLD development, partly attributed to the downregulation of MOGAT1 expression.

Galectin-3 and Severity of Liver Fibrosis in Metabolic Dysfunction-Associated Fatty Liver Disease

Metabolic dysfunction-associated Fatty Liver Disease (MAFLD) is a chronic liver disease characterized by the accumulation of fat in the liver and hepatic steatosis, which can progress to critical conditions, including Metabolic dysfunction-associated Steatohepatitis (MASH), liver fibrosis, hepatic cirrhosis, and hepatocellular carcinoma. Galectin-3, a member of the galectin family of proteins, has been involved in cascades that are responsible for the pathogenesis and progression of liver fibrosis in MAFLD. This review summarizes the present understanding of the role of galectin-3 in the severity of MAFLD and its associated liver fibrosis. The article assesses the underlying role of galectin-3-mediated fibrogenesis, including the triggering of hepatic stellate cells, the regulation of extracellular degradation, and the modulation of immune reactions and responses. It also highlights the assessments of the potential diagnostic and therapeutic implications of galectin-3 in liver fibrosis during MAFLD. Overall, this review provides insights into the multifaceted interaction between galectin-3 and liver fibrosis in MAFLD, which could lead to the development of novel strategies for diagnosis and treatment of this prevalent liver disease.

Effects of monochromatic light on hepatic glycogen and lipid synthesis in broilers

Animal growth is closely related to glycolipid metabolism, and the liver is the main organ for glycogen storage and fat synthesis in birds, but whether monochromatic light affects glycogen and lipid synthesis in the liver is unclear. Therefore, in this study, a total of 96 Arbor Acre (AA) broilers at posthatching d 0 (P0) were raised under 4 kinds of light-emitting diode (LED) lights, white light (WL), red light (RL), green light (GL), and blue light (BL), to posthatching d 21 (P21) and 35 (P35). The results showed that the liver, abdominal fat, and abdominal fat indices gradually increased with increasing age under monochromatic light treatments. The liver glycogen and triglyceride (TG) contents also showed an increasing trend. Furthermore, compared with those at P21, the mRNA levels of glycogen synthase (GS), glycogen synthase kinase-3β (GSK-3β), and protein kinase B (AKT1) in the liver were increased in the WL and RL groups at P35, and the mRNA levels of acetyl-CoA carboxylase (ACC) and apolipoprotein B (APOB) increased in all groups at P35. At the same time, the total antioxidant capacity (T-AOC) and liver superoxide dismutase (SOD) contents increased in all groups at P35 compared with those at P21. In addition, at P21, compared with WL, GL and BL promoted the serum glucose (GLU) and TG contents by increasing the mRNA levels of GS, GSK-3β, glucose-6-phosphatase (G6PC), ACC, and fatty acid synthase (FAS), but no effect on the proliferative ability and damage of hepatocytes. At P35, RL promoted the hepatic glycogen and TG contents by increasing GSK-3β, AKT1, ACC, and APOB mRNA levels, and the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were increased than in the WL group. These results suggest that the effects of light color on liver glycogen and lipid synthesis in broilers changed with age, and also provide a theoretical guidance for scientific use of color of light information to improve productive performance in broilers.

Mitochondrial Quality Control: Its Role in Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease, is characterized by hepatic steatosis and metabolic dysfunction and is often associated with obesity and insulin resistance. Recent research indicates a rapid escalation in MASLD cases, with projections suggesting a doubling in the United States by 2030. This review focuses on the central role of mitochondria in the pathogenesis of MASLD and explores potential therapeutic interventions. Mitochondria are dynamic organelles that orchestrate hepatic energy production and metabolism and are critically involved in MASLD. Dysfunctional mitochondria contribute to lipid accumulation, inflammation, and liver fibrosis. Genetic associations further underscore the relationship between mitochondrial dynamics and MASLD susceptibility. Although U.S. Food and Drug Administration-approved treatments for MASLD remain elusive, ongoing clinical trials have highlighted promising strategies that target mitochondrial dysfunction, including vitamin E, metformin, and glucagon-like peptide-1 receptor agonists. In preclinical studies, novel therapeutics, including nicotinamide adenine dinucleotide+ precursors, urolithin A, spermidine, and mitoquinone, have shown beneficial effects, such as improving mitochondrial quality control, reducing oxidative stress, and ameliorating hepatic steatosis and inflammation. In conclusion, mitochondrial dysfunction is central to MASLD pathogenesis. The innovative mitochondria-targeted approaches discussed in this review offer a promising avenue for reducing the burden of MASLD and improving global quality of life.

Melatonin Prevents Alcohol- and Metabolic Dysfunction- Associated Steatotic Liver Disease by Mitigating Gut Dysbiosis, Intestinal Barrier Dysfunction, and Endotoxemia

Melatonin (MT) has often been used to support good sleep quality, especially during the COVID-19 pandemic, as many have suffered from stress-related disrupted sleep patterns. It is less known that MT is an antioxidant, anti-inflammatory compound, and modulator of gut barrier dysfunction, which plays a significant role in many disease states. Furthermore, MT is produced at 400-500 times greater concentrations in intestinal enterochromaffin cells, supporting the role of MT in maintaining the functions of the intestines and gut-organ axes. Given this information, the focus of this article is to review the functions of MT and the molecular mechanisms by which it prevents alcohol-associated liver disease (ALD) and metabolic dysfunction-associated steatotic liver disease (MASLD), including its metabolism and interactions with mitochondria to exert its antioxidant and anti-inflammatory activities in the gut-liver axis. We detail various mechanisms by which MT acts as an antioxidant, anti-inflammatory compound, and modulator of intestinal barrier function to prevent the progression of ALD and MASLD via the gut-liver axis, with a focus on how these conditions are modeled in animal studies. Using the mechanisms of MT prevention and animal studies described, we suggest behavioral modifications and several exogenous sources of MT, including food and supplements. Further clinical research should be performed to develop the field of MT in preventing the progression of liver diseases via the gut-liver axis, so we mention a few considerations regarding MT supplementation in the context of clinical trials in order to advance this field of research.

Mitochondrial Dysfunction in Metabolic Dysfunction Fatty Liver Disease (MAFLD)

Nonalcoholic fatty liver disease (NAFLD) has become an increasingly common disease in Western countries and has become the major cause of liver cirrhosis or hepatocellular carcinoma (HCC) in addition to viral hepatitis in recent decades. Furthermore, studies have shown that NAFLD is inextricably linked to the development of extrahepatic diseases. However, there is currently no effective treatment to cure NAFLD. In addition, in 2020, NAFLD was renamed metabolic dysfunction fatty liver disease (MAFLD) to show that its pathogenesis is closely related to metabolic disorders. Recent studies have reported that the development of MAFLD is inextricably associated with mitochondrial dysfunction in hepatocytes and hepatic stellate cells (HSCs). Simultaneously, mitochondrial stress caused by structural and functional disorders stimulates the occurrence and accumulation of fat and lipo-toxicity in hepatocytes and HSCs. In addition, the interaction between mitochondrial dysfunction and the liver-gut axis has also become a new point during the development of MAFLD. In this review, we summarize the effects of several potential treatment strategies for MAFLD, including antioxidants, reagents, and intestinal microorganisms and metabolites.

Mitochondria- and NOX4-dependent antioxidant defense mitigates progression to nonalcoholic steatohepatitis in obesity

Nonalcoholic fatty liver disease (NAFLD) is prevalent in the majority of individuals with obesity, but in a subset of these individuals, it progresses to nonalcoholic steatohepatitis (0NASH) and fibrosis. The mechanisms that prevent NASH and fibrosis in the majority of patients with NAFLD remain unclear. Here, we report that NAD(P)H oxidase 4 (NOX4) and nuclear factor erythroid 2-related factor 2 (NFE2L2) were elevated in hepatocytes early in disease progression to prevent NASH and fibrosis. Mitochondria-derived ROS activated NFE2L2 to induce the expression of NOX4, which in turn generated H2O2 to exacerbate the NFE2L2 antioxidant defense response. The deletion or inhibition of NOX4 in hepatocytes decreased ROS and attenuated antioxidant defense to promote mitochondrial oxidative stress, damage proteins and lipids, diminish insulin signaling, and promote cell death upon oxidant challenge. Hepatocyte NOX4 deletion in high-fat diet-fed obese mice, which otherwise develop steatosis, but not NASH, resulted in hepatic oxidative damage, inflammation, and T cell recruitment to drive NASH and fibrosis, whereas NOX4 overexpression tempered the development of NASH and fibrosis in mice fed a NASH-promoting diet. Thus, mitochondria- and NOX4-derived ROS function in concert to drive a NFE2L2 antioxidant defense response to attenuate oxidative liver damage and progression to NASH and fibrosis in obesity.

A Comprehensive Review on Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD), now known as metabolic dysfunction-associated liver disease (MASLD), is a spectrum of liver disease. It can be identified by the fact that considerable amount of hepatocytes with minimal or no alcohol use have steatosis. Because of its rising incidence along with increasing rates of obesity, metabolic syndromes, and diabetes mellitus type 2, NAFLD is expected to overtake all other causes of cirrhosis over the next decade, necessitating liver transplantation. Nevertheless, heart disease persists as the most prevalent manifestation of mortality, with only a small percentage experiencing fibrosis and complications associated with the liver. Pathologically, NAFLD is linked to lipid toxicity, oxidative stress, lipid deposits, and endoplasmic reticulum stress. A healthy diet, physical exercise, and a decrease in weight are advised by current international guidelines for the treatment of NAFLD, along with a limited number of medicinal therapies, including vitamin E and pioglitazone. Various natural substances have also been identified as NAFLD in vivo and in vitro regulators. The frequency, complexity of the pathophysiology, lack of authorised medications, and difficulty in interpretation of NAFLD have made it a major problem. This article assesses MASLD's pathophysiology, diagnosis, treatment, and epidemiology. This study also reviews a few natural substances that have been shown to have therapeutic advantages for NAFLD.

A classical herbal formula alleviates high-fat diet induced nonalcoholic steatohepatitis (NASH) via targeting mitophagy to rehabilitate dysfunctional mitochondria, validated by UPLC-HRMS identification combined with in vivo experiment

BACKGROUND

Nonalcoholic steatohepatitis (NASH) has caused a significant burden on public health care systems, the economy and society. However, there has still been no officially approved pharmacotherapy for NASH. It has been suggested that oxidative stress and mitochondrial dysfunction play vital roles in NASH pathological progression. Shugan Xiaozhi (SG) formula, as a kind of classical herbal formula, was shown to attenuate NASH.

PURPOSE

This study aimed to explore the potential mechanisms of SG formula treating NASH.

STUDY DESIGN AND METHODS

Ultra-high-performance liquid chromatography-high resolution mass spectrometry combined with bioinformatics analysis was applied to explore the therapeutic targets and main components of SG formula. Moreover, in vivo NASH model was utilized to confirmed the therapeutic effects of SG formula. Molecular docking analysis and further validation experiments were conducted to verify the results of bioinformatics analysis.

RESULTS

The in vivo experiments confirmed SG formula significantly attenuated hepatic pathological progression and relieved oxidative stress in high-fat diet (HFD) induced - NASH model. Ultra-high-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) combined with bioinformatics analysis expounded the components of SG formula and revealed the mitochondrial regulation mechanism of SG formula treating NASH. Further in vivo experiments validated that SG formula could alleviate oxidative stress by rehabilitating the structure and function of mitochondria, which was strongly related to regulating mitophagy.

CONCLUSION

In summary, this study demonstrated that SG formula, which could attenuate NASH by regulating mitochondria and might be a potential pharmacotherapy for NASH.

Novel Role of Molecular Hydrogen: The End of Ophthalmic Diseases?

Molecular hydrogen (H2) is a colorless, odorless, and tasteless gas which displays non-toxic features at high concentrations. H2 can alleviate oxidative damage, reduce inflammatory reactions and inhibit apoptosis cascades, thereby inducing protective and repairing effects on cells. H2 can be transported into the body in the form of H2 gas, hydrogen-rich water (HRW), hydrogen-rich saline (HRS) or H2 produced by intestinal bacteria. Accumulating evidence suggest that H2 is protective against multiple ophthalmic diseases, including cataracts, dry eye disease, diabetic retinopathy (DR) and other fields. In particular, H2 has been tested in the treatment of dry eye disease and corneal endothelial injury in clinical practice. This medical gas has brought hope to patients suffering from blindness. Although H2 has demonstrated promising therapeutic potentials and broad application prospects, further large-scale studies involving more patients are still needed to determine its optimal application mode and dosage. In this paper, we have reviewed the basic characteristics of H2, and its therapeutic effects in ophthalmic diseases. We also focus on the latest progress in the administration approaches and mechanisms underlying these benefits.

Pharmacological effects of mTORC1/C2 inhibitor in a preclinical model of NASH progression

Knowledge of the benefits of mTOR inhibition concerning adipogenesis and inflammation has recently encouraged the investigation of a new generation of mTOR inhibitors for non-alcoholic steatohepatitis (NASH). We investigated whether treatment with a specific mTORC1/C2 inhibitor (Ku-0063794; KU) exerted any beneficial impacts on experimentally-induced NASH in vitro and in vivo. The results indicated that KU decreases palmitic acid-induced lipotoxicity in cultivated primary hepatocytes, thus emerging as a successful candidate for testing in an in vivo NASH dietary model, which adopted the intraperitoneal KU dosing route rather than oral application due to its significantly greater bioavailability in mice. The pharmacodynamics experiments commenced with the feeding of male C57BL/6 mice with a high-fat atherogenic western-type diet (WD) for differing intervals over several weeks aimed at inducing various phases of NASH. In addition to the WD, the mice were treated with KU for 3 weeks or 4 months. Acute and chronic KU treatments were observed to be safe at the given concentrations with no toxicity indications in the mice. KU was found to alleviate NASH-related hepatotoxicity, mitochondrial and oxidative stress, and decrease the liver triglyceride content and TNF-α mRNA in at least one set of in vivo experiments. The KU modulated liver expression of selected metabolic and oxidative stress-related genes depended upon the length and severity of the disease. Although KU failed to completely reverse the histological progression of NASH in the mice, we demonstrated the complexity of mTORC1/C2 signaling regulation and suggest a stratified therapeutic management approach throughout the disease course.

Dietary and lifestyle oxidative balance scores are independently and jointly associated with nonalcoholic fatty liver disease: a 20 years nationally representative cross-sectional study

Background

Oxidative stress is an important contributor to the progression of nonalcoholic fatty liver disease (NAFLD), but whether dietary and lifestyle pro- and antioxidants may have combined or independent effects on NAFLD, and advanced liver fibrosis (AHF) remains unclear. We aimed to elucidate the relationship between a well-established oxidative balance score (OBS) and NAFLD/AHF.

Methods

This was a cross-sectional study. We included adult participants with complete data from the National Health and Nutrition Examination Survey 1999-2018. Survey-weighted adjusted multivariate regression analyses were used to examine the association of all OBS with NAFLD/AHF. A combination of restricted cubic splines, mediation analysis, stratified analysis, and sensitivity analysis were used to further elucidate these associations.

Results

We included 6,341 eligible adult participants with prevalence of NAFLD and AHF of 30.2 and 13.9%, respectively. In the fully adjusted model, the highest quartile of OBS, dietary OBS, and lifestyle OBS were associated with 65, 55, and 77% reduced risk of NAFLD, respectively, compared with the reference population, respectively. However, all OBS were not associated with the risk of AHF. All OBS were nonlinearly associated with risk of NAFLD and had a more pronounced reduced risk for OBS, dietary OBS, and lifestyle OBS after exceeding 26, 21, and 5 points, respectively. OBS may exert a protective effect indirectly through inflammation, oxidative stress, and glycolipid metabolism markers. Stratification and sensitivity analyses demonstrate the robustness of our findings.

Conclusion

All OBS were nonlinearly and negatively associated with NAFLD risk. These effects may exert indirectly through inflammation, oxidative stress, and glycolipid metabolism markers.

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.

Neonatal nicotine exposure affects adult rat hepatic pathways involved in endoplasmic reticulum stress and macroautophagy in a sex-dependent manner

Nonalcoholic fatty liver disease (NAFLD) involves changes in hepatic pathways, as lipogenesis, oxidative stress, endoplasmic reticulum (ER) stress, and macroautophagy. Maternal nicotine exposure exclusively during lactation leads to fatty liver (steatosis) only in the adult male offspring, not in females. Therefore, our hypothesis is that neonatal exposure to nicotine sex-dependently affects the signaling pathways involved in hepatic homeostasis of the offspring, explaining the hepatic lipid accumulation phenotype only in males. For this, between postnatal days 2 and 16, Wistar rat dams were implanted with osmotic minipumps, which released nicotine (NIC; 6 mg/Kg/day) or vehicle. The livers of offspring were evaluated at postnatal day 180. Only the male offspring that had been exposed to nicotine neonatally showed increased protein expression of markers of unfolded protein response (UPR), highlighting the presence of ER stress, as well as disruption of the activation of the macroautophagy repair pathway. These animals also had increased expression of diacylglycerol O-acyltransferase 1 and 4-hydroxynonenal, suggesting increased triglyceride esterification and oxidative stress. These parameters were not altered in the female offspring that had been neonatally exposed to nicotine, however they exhibited increased phospho adenosine monophosphate-activated protein kinase pAMPK expression, possibly as a protective mechanism. Thus, the disturbance in the hepatic homeostasis by UPR, macroautophagy, and oxidative stress modifications seem to be the molecular mechanisms underlying the liver steatosis in the adult male offspring of the nicotine-programming model. This highlights the importance of maternal smoking cessation during breastfeeding to decrease the risk of NAFLD development, especially in males.

MKP1 promotes nonalcoholic steatohepatitis by suppressing AMPK activity through LKB1 nuclear retention

Nonalcoholic steatohepatitis (NASH) is triggered by hepatocyte death through activation of caspase 6, as a result of decreased adenosine monophosphate (AMP)-activated protein kinase-alpha (AMPKα) activity. Increased hepatocellular death promotes inflammation which drives hepatic fibrosis. We show that the nuclear-localized mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP1) is upregulated in NASH patients and in NASH diet fed male mice. The focus of this work is to investigate whether and how MKP1 is involved in the development of NASH. Under NASH conditions increased oxidative stress, induces MKP1 expression leading to nuclear p38 MAPK dephosphorylation and decreases liver kinase B1 (LKB1) phosphorylation at a site required to promote LKB1 nuclear exit. Hepatic deletion of MKP1 in NASH diet fed male mice releases nuclear LKB1 into the cytoplasm to activate AMPKα and prevents hepatocellular death, inflammation and NASH. Hence, nuclear-localized MKP1-p38 MAPK-LKB1 signaling is required to suppress AMPKα which triggers hepatocyte death and the development of NASH.

Kaempferol attenuates nonalcoholic fatty liver disease in type 2 diabetic mice via the Sirt1/AMPK signaling pathway

Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver diseases with limited treatment options. Moreover, its prevalence is doubled in type 2 diabetes mellitus (T2DM). Kaempferol (KAP) is a flavonoid compound that has been suggested to have beneficial effects on NAFLD, but studies on the mechanism are lacking, especially in the diabetic state. Herein, we investigated the effect of KAP on NAFLD associated with T2DM and its underlying mechanism in vitro and in vivo. The results of in vitro studies indicated that KAP treatment (10-8-10-6 M) significantly reduced lipid accumulation in oleic acid-induced HepG2 cells. Moreover, in the T2DM animal model of db/db mice, we confirmed that KAP (50 mg/kg) significantly reduced lipid accumulation and improved liver injury. Mechanistic studies in vitro and in vivo showed that Sirtuin 1 (Sirt1)/AMP-activated protein kinase (AMPK) signal was involved in KAP regulation of hepatic lipid accumulation. KAP treatment activated Sirt1 and AMPK, upregulated the levels of fatty acid oxidation-related protein proliferator activated receptor gamma coactivator 1α (PGC1α); and downregulated lipid synthesis-related proteins, including acetyl-coA carboxylase (ACC), fatty acid synthase (FASN), and sterol regulatory element-binding protein 1 (SREBP1). Furthermore, the curative effect of KAP on lipid accumulation was abolished by siRNA-mediated knockdown of either Sirt1 or AMPK. Collectively, these findings suggest that KAP may be a potential therapeutic agent for NAFLD associated with T2DM by regulating hepatic lipid accumulation through activation of Sirt1/AMPK signaling.

Activation of Kupffer cells in NAFLD and NASH: mechanisms and therapeutic interventions

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are emerging as the leading causes of liver disease worldwide. These conditions can lead to cirrhosis, liver cancer, liver failure, and other related ailments. At present, liver transplantation remains the sole treatment option for end-stage NASH, leading to a rapidly growing socioeconomic burden. Kupffer cells (KCs) are a dominant population of macrophages that reside in the liver, playing a crucial role in innate immunity. Their primary function includes phagocytosing exogenous substances, presenting antigens, and triggering immune responses. Moreover, they interact with other liver cells during the pathogenesis of NAFLD, and this crosstalk may either delay or exacerbate disease progression. Stimulation by endogenous signals triggers the activation of KCs, resulting in the expression of various inflammatory factors and chemokines, such as NLRP3, TNF-α, IL-1B, and IL-6, and contributing to the inflammatory cascade. In the past 5 years, significant advances have been made in understanding the biological properties and immune functions of KCs in NAFLD, including their interactions with tissue molecules, underlying molecular mechanisms, signaling pathways, and relevant therapeutic interventions. Having a comprehensive understanding of these mechanisms and characteristics can have enormous potential in guiding future strategies for the prevention and treatment of NAFLD.

Neuroprotective mechanisms of OXCT1 via the SIRT3-SOD2 pathway after traumatic brain injury

BACKGROUND

Ketones are not only utilized to produce energy but also play a neuroprotective role in many neurodegenerative diseases. However, whether this process has an impact on secondary brain damage after traumatic brain injury (TBI) remains unknown. OXCT1 (3-Oxoacid CoA-Transferase 1) is the rate-limiting enzyme in the intra-neuronal utilization of ketones. In this study, we investigated whether reduced expression of OXCT1 after TBI could impact neuroprotective mechanisms and exacerbate neurological dysfunction.

MATERIALS AND METHODS

Experimental TBI was induced by a modified version of the weight drop model, it is a model of severe head trauma. Expression of OXCT1 in the injured hippocampus of mice was measured at different time points using immunoblotting assays. The release of abnormal mitochondrial cytochrome c from neurons of the mouse injured lateral hippocampus was measured 1 week after TBI using immunoblotting assays. Neuronal death was assessed by Nissl staining and the level of reactive oxygen species (ROS) within the neurons of the injured lateral hippocampus was assessed by Dihydroethidium staining. Results OXCT1 was overexpressed in hippocampal neurons by injection of adeno-associated virus into the lateral ventricle. OXCT1 expression levels decreased significantly 1 week post-TBI. After comparing the data obtained from different groups of mice, OXCT1 was found to significantly increase the expression of SIRT3 and reduce the proportion of acetylated SOD2, thus decreasing the production of ROS in the injured hippocampal neurons, reducing neuronal death, and improving cognitive function. Conclusions OXCT1 has a critical previously unappreciated protective role in neurological impairment following TBI via the SIR3-SOD2 pathway. These findings highlight the potential of OXCT1 as a simple treatment for patients with TBI.

Flavonoids from Scutellaria amoena C. H. Wright alleviate mitochondrial dysfunction and regulate oxidative stress via Keap1/Nrf2/HO-1 axis in rats with high-fat diet-induced nonalcoholic steatohepatitis

BACKGROUND

Nonalcoholic steatohepatitis (NASH) is among the most common liver diseases in the world. Flavonoids from Scutellaria amoena (SAF) are used in the treatment of hepatopathy in China. However, the effect and mechanism against NASH remain unclear. We investigated the alleviating effect of SAF on NASH via regulating mitochondrial dysfunction and oxidative stress.

METHODS

The effects of SAF on NASH were evaluated using in vitro and in vivo methods. L02 cells were induced by fat emulsion to establish an adipocytes model, followed by treatment with SAF for 24 h. NASH rat models were established by the administration of a high-fat diet for 12 weeks and were administered SAF for six weeks. Changes in body weight, organ indexes, lipid levels, inflammatory cytokines, mitochondrial indicators, and fatty acid metabolism were investigated.

RESULTS

SAF significantly improved body weight, organ indexes, lipid levels, liver injury, and inflammatory infiltration in NASH rats. SAF notably regulated interleukin-6, tumor necrotic factor-alpha, superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), kelch-like ECH-associated protein 1 (Keap1), nuclear factor-erythroid factor 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1). Additionally, SAF improved mitochondrial dysfunction, increased the levels of GSH, SOD, ATP synthase, complex I and II, and decreased the level of MDA in liver mitochondria. SAF regulated the expression of β-oxidation genes, including peroxisome proliferator-activated receptor -gamma coactivator-1alpha (PGC-1α), carnitine palmitoyltransferase-1 (CPT1) A, CPT1B, medium-chain acyl-CoA dehydrogenase, long-chain acyl-CoA dehydrogenase, very long-chain acyl-CoA dehydrogenase, and PPARα.

CONCLUSION

SAF can alleviate NASH by regulating mitochondrial function and oxidative stress via the Keap1/Nrf2/HO-1 axis.

Drug-induced mitochondrial toxicity: Risks of developing glucose handling impairments

Mitochondrial impairment has been associated with the development of insulin resistance, the hallmark of type 2 diabetes mellitus (T2DM). However, the relationship between mitochondrial impairment and insulin resistance is not fully elucidated due to insufficient evidence to support the hypothesis. Insulin resistance and insulin deficiency are both characterised by excessive production of reactive oxygen species and mitochondrial coupling. Compelling evidence states that improving the function of the mitochondria may provide a positive therapeutic tool for improving insulin sensitivity. There has been a rapid increase in reports of the toxic effects of drugs and pollutants on the mitochondria in recent decades, interestingly correlating with an increase in insulin resistance prevalence. A variety of drug classes have been reported to potentially induce toxicity in the mitochondria leading to skeletal muscle, liver, central nervous system, and kidney injury. With the increase in diabetes prevalence and mitochondrial toxicity, it is therefore imperative to understand how mitochondrial toxicological agents can potentially compromise insulin sensitivity. This review article aims to explore and summarise the correlation between potential mitochondrial dysfunction caused by selected pharmacological agents and its effect on insulin signalling and glucose handling. Additionally, this review highlights the necessity for further studies aimed to understand drug-induced mitochondrial toxicity and the development of insulin resistance.

Selective disruption of NRF2-KEAP1 interaction leads to NASH resolution and reduction of liver fibrosis in mice

Background & Aims

Oxidative stress is recognized as a major driver of non-alcoholic steatohepatitis (NASH) progression. The transcription factor NRF2 and its negative regulator KEAP1 are master regulators of redox, metabolic and protein homeostasis, as well as detoxification, and thus appear to be attractive targets for the treatment of NASH.

Methods

Molecular modeling and X-ray crystallography were used to design S217879 - a small molecule that could disrupt the KEAP1-NRF2 interaction. S217879 was highly characterized using various molecular and cellular assays. It was then evaluated in two different NASH-relevant preclinical models, namely the methionine and choline-deficient diet (MCDD) and diet-induced obesity NASH (DIO NASH) models.

Results

Molecular and cell-based assays confirmed that S217879 is a highly potent and selective NRF2 activator with marked anti-inflammatory properties, as shown in primary human peripheral blood mononuclear cells. In MCDD mice, S217879 treatment for 2 weeks led to a dose-dependent reduction in NAFLD activity score while significantly increasing liver Nqo1 mRNA levels, a specific NRF2 target engagement biomarker. In DIO NASH mice, S217879 treatment resulted in a significant improvement of established liver injury, with a clear reduction in both NAS and liver fibrosis. αSMA and Col1A1 staining, as well as quantification of liver hydroxyproline levels, confirmed the reduction in liver fibrosis in response to S217879. RNA-sequencing analyses revealed major alterations in the liver transcriptome in response to S217879, with activation of NRF2-dependent gene transcription and marked inhibition of key signaling pathways that drive disease progression.

Conclusions

These results highlight the potential of selective disruption of the NRF2-KEAP1 interaction for the treatment of NASH and liver fibrosis.

Impact and implications

We report the discovery of S217879 - a potent and selective NRF2 activator with good pharmacokinetic properties. By disrupting the KEAP1-NRF2 interaction, S217879 triggers the upregulation of the antioxidant response and the coordinated regulation of a wide spectrum of genes involved in NASH disease progression, leading ultimately to the reduction of both NASH and liver fibrosis progression in mice.

Genetic Variation of SAMM50 Is Not an Independent Risk Factor for Alcoholic Hepatocellular Carcinoma in Caucasian Patients

Hepatocellular carcinoma (HCC) is a severe complication of advanced alcoholic liver disease, which is modulated by genetic predisposition. Identifying new genetic loci might improve screening. Genetic variation of SAMM50 was linked to HCC. We aimed to validate this finding in a large cohort of patients with advanced alcoholic liver disease (ALD). A large, well-characterised cohort of patients with alcoholic cirrhosis without (n = 674) and with (n = 386) HCC, as well as controls with HCC due to viral hepatitis (n = 134), controls with heavy alcohol abuse without liver disease (n = 266) and healthy subjects (n = 237), were genotyped for SAMM50 rs3827385 and rs3761472 and for PNPLA3 rs738409. Genotype frequencies were compared between patients with alcohol-associated cirrhosis with and without HCC by uni- and multivariate analysis. Minor variants in both SAMM50 rs3827385 and rs3761472 were significantly more frequent in patients with alcoholic HCC versus alcoholic cirrhosis and versus the control cohorts. An even stronger association was noted for PNPLA3 rs738409. The univariate analysis resulted in an odds ratio (OR) of 1.8 for carriers of at least one minor variant of SAMM50 rs3827385 and rs3761472 (each p < 0.001), but this association was lost in multivariate analysis with age (OR 1.1/year), male sex (OR 3.2), diabetes (OR 1.9) and carriage of PNPLA3 148M (OR 2.1) remaining in the final model. Although minor variants of both SAMM50 loci are strongly associated with alcoholic HCC, this association is not independent of carriage of the well-known risk variant PNPLA3 148M.

Non-alcoholic fatty liver disease establishment and progression: genetics and epigenetics as relevant modulators of the pathology

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) results from metabolic dysfunctions that affect more than one-third of the world population. Over the last decades, scientific investigations have clarified many details on the pathology establishment and development; however, effective therapeutics approaches are still evasive. In addition, studies demonstrated that NAFLD establishment and progression are related to several etiologies. Recently, genetics and epigenetics backgrounds have emerged as relevant elements to the pathology onset, and, hence, deserve deep investigation to clarify molecular details on NAFLD signaling, which may be correlated with population behavior. Thus, to minimize the global problem, public health and public policies should take advantage of studies on NAFLD over the next following decades.

METHODS

In this context, we have performed a selective literature review focusing on biochemistry of lipid metabolism, genetics, epigenetics, and the ethnicity as strong elements that drive NAFLD establishment.

RESULTS

Considering the etiological agents that acts on NAFLD development and progression, the genetics and the epigenetics emerged as relevant factors. Genetics acts as a powerful element in the establishment and progression of the NAFLD. Over the last decades, details concerning genes and their polymorphisms, as well as epigenetics, have been considered relevant elements in the systems biology of diseases, and their effects on NAFLD should be considered in-depth, as well as the ethnicity, clarifying whether people are susceptible to liver diseases. Moreover, the endemicity and social problems of hepatic disfunction are far to be solved, which require a combined effort of various sectors of society.

CONCLUSION

Hence, the elements presented and discussed in this short review demonstrated their relevance to the physiological control of NAFLD, opening perspectives for research to develop new strategy to treat fatty liver diseases.