Reactive Oxygen Species Induce Fatty Liver and Ischemia-Reperfusion Injury by Promoting Inflammation and Cell Death

Glycogen synthase kinase-3β: A multifaceted player in ischemia-reperfusion injury and its therapeutic prospects

Ischemia-reperfusion injury (IRI) results in irreversible metabolic dysfunction and structural damage to tissues or organs, posing a formidable challenge in the field of organ implantation, cardiothoracic surgery, and general surgery. Glycogen synthase kinase-3β (GSK-3β) a multifunctional serine/threonine kinase, is involved in a variety of biological processes, including cell proliferation, apoptosis, and immune response. Phosphorylation of its tyrosine 216 and serine 9 sites positively and negatively regulates the activation and inactivation of the enzyme. Significantly, inhibition or inactivation of GSK-3β provides protection against IRI, making it a viable target for drug development. Though numerous GSK-3β inhibitors have been identified to date, the development of therapeutic treatments remains a considerable distance away. In light of this, this review summarizes the complicated network of GSK-3β roles in IRI. First, we provide an overview of GSK-3β's basic background. Subsequently, we briefly review the pathological mechanisms of GSK-3β in accelerating IRI, and highlight the latest progress of GSK-3β in multiorgan IRI, encompassing heart, brain, kidney, liver, and intestine. Finally, we discuss the current development of GSK-3β inhibitors in various organ IRI, offering a thorough and insightful reference for GSK-3β as a potential target for future IRI therapy.

Mechanism of Reactive Oxygen/Nitrogen Species in Liver Ischemia-Reperfusion Injury and Preventive Effect of Chinese Medicine

Liver ischemia-reperfusion injury (LIRI) is a pathological process involving multiple injury factors and cell types, with different stages. Currently, protective drugs targeting a single condition are limited in efficacy, and interventions on immune cells will also be accompanied by a series of side effects. In the current bottleneck research stage, the multi-target and obvious clinical efficacy of Chinese medicine (CM) is expected to become a breakthrough point in the research and development of new drugs. In this review, we summarize the roles of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in various stages of hepatic ischemia-reperfusion and on various types of cells. Combined with the current research progress in reducing ROS/RNS with CM, new therapies and mechanisms for the treatment of hepatic ischemia-reperfusion are discussed.

TXNIP knockdown ameliorates hepatic ischemia/reperfusion injury by inhibiting apoptosis and improving mitochondrial dysfunction via HIF-1α

This study aims to investigate whether thioredoxin-interacting protein (TXNIP) regulates cell viability, cell apoptosis and mitochondrial damage in OGD/R-induced hepatocytes and to explore its underlying mechanism. AML12 cells were cultured under oxygen-glucose deprivation/reperfusion (OGD/R) conditions. TXNIP mRNA was detected using qRT-PCR, and the TXNIP protein was analyzed using western blotting. TXNIP-targeted short hairpin RNA (sh-TXNIP) lentivirus was used to infect the AML12 cells. CCK8 and TUNEL assays were applied to detect cell viability and apoptosis, respectively. DCFH-DA probe was used to determine reactive oxygen species (ROS) release level, and JC-1 probe was used to evaluate mitochondrial membrane potential (MMP). The localization of TXNIP and HIF-1α was observed using immunofluorescence. Our results showed that TXNIP markedly increased in AML12 cells treated with OGD/R. TXNIP knockdown increased cell viability and reduced cell apoptosis under OGD/R treatment. Moreover, MMP significantly increased and ROS release decreased in cells after TXNIP knockdown under OGD/R treatment. Additionally, TXNIP knockdown markedly increased the expression of HIF-1α. HIF-1α exhibited nuclear translocation following OGD/R induction, and TXNIP knockdown further promoted it. Compared with the OGD/R + sh-TXNIP group, HIF-1α agonist ML228 inhibited cell apoptosis and ROS release, and increased MMP. However, HIF-1α inhibitor PX478 had the opposite effect. In summary, TXNIP deletion ameliorated AML12 cell injury caused by OGD/R via promoting HIF-1α expression and nuclear translocation, manifested by inhibiting cell apoptosis and alleviating mitochondrial dysfunction.

In Vitro Nonalcoholic Fatty Liver Disease Model Elucidating the Effect of Immune Environment on Disease Progression and Alleviation

Nonalcoholic fatty liver disease (NAFLD), which is a major cause of chronic liver disease, is characterized by fat accumulation in the liver. Existing models struggle to assess medication effects on liver function in the context of NAFLD's unique inflammatory environment. We address this by developing a 3D in vitro NAFLD model using HepG2 and THP-1 cells (mimicking liver and Kupffer cells) cocultured using transwell and hydrogel system. This mimics liver architecture and allows for manipulation of the immune environment. We demonstrate that the model recapitulates key NAFLD features: steatosis (induced by fatty acids), oxidative stress, inflammation, and impaired liver function embodying the interrelationship between NAFLD and the surrounding immune environment. This versatile model offers a valuable tool for preclinical NAFLD research by incorporating a disease-relevant immune environment.

Effect of liver transplants with retrograde reperfusion on early postoperative recovery of liver function and its risk factors

BACKGROUND

The purpose of this study was to investigate effect of liver Transplants (LT) with retrograde reperfusion on early postoperative recovery of liver function and its risk factors.

METHODS

We conducted a retrospective analysis of clinical data from 136 liver transplantation (LT) patients at the 900th Hospital of the Chinese People's Liberation Army Joint Support Army, covering the period from January 2015 to January 2021. All participants provided informed consent, adhering to medical ethics guidelines. Patients were stratified into two groups based on the liver perfusion technique used: retrograde reperfusion (RTR, n = 108) and initial portal reperfusion (IPR, n = 28). Our study focused on a subset of 23 patients from each group to compare postoperative liver function recovery. The final analysis included 86 RTR and 28 IPR cases after excluding 8 RTR patients who underwent initial hepatic artery reperfusion and 14 who received simultaneous hepatic artery and portal vein reperfusion. Further subdivision within the RTR group identified 19 patients with early hepatic allograft dysfunction (EAD) and 67 without, allowing for an assessment of the influence of preoperative and intraoperative parameters, as well as perfusion methods, on EAD incidence post-LT.

RESULTS

Alanine aminotransferase (ALT) was 329 (211 ~ 548) and 176 (98 ~ 282) U/L on the 3rd and 7th day after RTR, respectively, which was significantly lower than 451 (288 ~ 918) and 251 (147 ~ 430) U/L in the IPR group (Z =-1.979, -2.299, P = 0.048, 0.021). Aspartate aminotransferase (AST) on postoperative days 3, 5, and 7 was 252 (193, 522), 105 (79, 163), and 93 (41, 135) U/L in the RTR group, respectively; it was also significantly lower than 328 (251, 724), 179 (129, 306), and 150 (91, 200)U/L in the IPR group (Z=-2.212, -3.221, -2.979; P = 0.027, 0.001, 0.003). Logistic regression analysis showed that MELD score was an independent risk factor for EAD after LT.

CONCLUSION

RTR LT is more favorable for patients' early postoperative liver function recovery. For patients undergoing LT for RTR, preoperative MELD score was an independent risk factor for their postoperative development of EAD.

High-dose sinomenine attenuates ischemia/reperfusion-induced hepatic inflammation and oxidative stress in rats with diabetes mellitus

INTRODUCTION

Ischemia-reperfusion (I/R) injury, resulting from blood flow interruption and its subsequent restoration, is a prevalent complication in liver surgery. The liver, as a crucial organ for carbohydrate and lipid metabolism, exhibits decreased tolerance to hepatic I/R in patients with diabetes mellitus (DM), resulting in a significant increase in hepatic dysfunction following surgery. This may be attributed to elevated oxidative stress and inflammation. Our prior research established sinomenine's (SIN) protective role against hepatic I/R injury. Nevertheless, the impact of SIN on hepatic I/R injury in DM rats remains unexplored.

OBJECTIVE AND METHODS

This study aimed to investigate the therapeutic potential of SIN in hepatic I/R injury in DM rats and elucidate its mechanism. Diabetic and hepatic I/R injury models were established in rats through high-fat/sugar diet, streptozotocin injection, and hepatic blood flow occlusion. Liver function, oxidative stress, inflammatory reaction, histopathology, and Nrf-2/HO-1 signaling pathway were evaluated by using UV spectrophotometry, biochemical assays, enzyme-linked immunosorbent assay, hematoxylin-eosin staining, and Western blot analysis.

RESULTS

High-dose SIN (300 mg/kg) significantly attenuated hepatic I/R injury in DM rats, reducing serum activities of ALT and AST, decreasing the AST/ALT ratio, enhancing tissue contents of SOD and GSH-Px, suppressing the levels of TNF-α and IL-6, improving the liver histopathology, and activating Nrf-2/HO-1 signaling by promoting Nrf-2 trans-location from cytoplasm to nucleus. Low-dose SIN (100 mg/kg) was ineffective.

CONCLUSIONS

This study demonstrates that high-dose sinomenine's mitigates hepatic I/R-induced inflammation and oxidative stress in diabetes mellitus (DM) rats via Nrf-2/HO-1 activation, suggesting its potential as a preventive strategy for hepatic I/R injury in DM patients.

Enzyme-Treated Zizania latifolia Ethanol Extract Improves Liver-Related Outcomes and Fatigability

Long-term hepatic damage is associated with human morbidity and mortality owing to numerous pathogenic factors. A variety of studies have focused on improving liver health using natural products and herbal medicines. We aimed to investigate the effect of enzyme-treated Zizania latifolia ethanol extract (ETZL), which increases the content of tricin via enzymatic hydrolysis, for 8 weeks on liver-related outcomes, lipid metabolism, antioxidant activity, and fatigue compared to a placebo. Healthy Korean adult males aged 19-60 years were randomized into ETZL treatment and placebo groups, and alcohol consumption was 24.96 and 28.64 units/week, respectively. Alanine transaminase, a blood marker associated with liver cell injury, significantly decreased after 8 weeks compared to the baseline in the ETZL treatment group (p = 0.004). After 8 weeks, the treatment group showed significant changes in the levels of high-density lipoprotein and hepatic steatosis index compared to the baseline (p = 0.028 and p = 0.004, respectively). ETZL treatment tended to reduce antioxidant-activity-related factors, total antioxidant status, and malondialdehyde, but there was no significant difference. In the multidimensional fatigue scale, ETZL treatment showed a significant reduction in general fatigue and total-fatigue-related values after 8 weeks compared to the baseline (p = 0.012 and p = 0.032, respectively). Taken together, the 8-week treatment of enzyme-treated Zizania latifolia ethanol extract demonstrated positive effects on liver-related outcomes, lipid metabolism, and mental fatigue without adverse effects on safety-related parameters.

Decreased Hepatic and Serum Levels of IL-10 Concur with Increased Lobular Inflammation in Morbidly Obese Patients

Background and Objectives: Non-alcoholic fatty liver disease (NAFLD) is associated with obesity and ranges from simple steatosis to non-alcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and hepatocellular carcinoma. Accumulating evidence in animal models suggests that loss of interleukin-10 (IL-10) anti-inflammatory actions might contribute to lobular inflammation, considered one of the first steps toward NASH development. However, the role of IL-10 in lobular inflammation remains poorly explored in humans. We examined mRNA and protein levels of IL-10 in liver biopsies and serum samples from morbidly obese patients, investigating the relationship between IL-10 and lobular inflammation degree. Materials and Methods: We prospectively enrolled morbidly obese patients of both sexes, assessing the lobular inflammation grade by the Brunt scoring system to categorize participants into mild (n = 7), moderate (n = 19), or severe (n = 13) lobular inflammation groups. We quantified the hepatic mRNA expression of IL-10 by quantitative polymerase chain reaction and protein IL-10 levels in liver and serum samples by Luminex Assay. We estimated statistical differences by one-way analysis of variance (ANOVA) and Tukey's multiple comparison test. Results: The hepatic expression of IL-10 significantly diminished in patients with severe lobular inflammation compared with the moderate lobular inflammation group (p = 0.01). The hepatic IL-10 protein levels decreased in patients with moderate or severe lobular inflammation compared with the mild lobular inflammation group (p = 0.008 and p = 0.0008, respectively). In circulation, IL-10 also significantly decreased in subjects with moderate or severe lobular inflammation compared with the mild lobular inflammation group (p = 0.005 and p < 0.0001, respectively). Conclusions: In liver biopsies and serum samples of morbidly obese patients, the protein levels of IL-10 progressively decrease as lobular inflammation increases, supporting the hypothesis that lobular inflammation develops because of the loss of the IL-10-mediated anti-inflammatory counterbalance.

Unveiling the role of disulfidptosis-related genes in the pathogenesis of non-alcoholic fatty liver disease

Backgrounds

Non-alcoholic fatty liver disease (NAFLD) presents as a common liver disease characterized by an indistinct pathogenesis. Disulfidptosis is a recently identified mode of cell death. This study aimed to investigate the potential role of disulfidptosis-related genes (DRGs) in the pathogenesis of NAFLD.

Methods

Gene expression profiles were obtained from the bulk RNA dataset GSE126848 and the single-cell RNA dataset GSE136103, both associated with NAFLD. Our study assessed the expression of DRGs in NAFLD and normal tissues. Weighted gene co-expression network analysis (WGCNA) and differential expression analysis were employed to identify the key NAFLD-specific differentially expressed DRGs (DE-DRGs). To explore the biological functions and immune regulatory roles of these key DE-DRGs, we conducted immune infiltration analysis, functional enrichment analysis, consensus clustering analysis, and single-cell differential state analysis. Finally, we validated the expression and biological functions of DRGs in NAFLD patients using histology and RNA-sequencing transcriptomic assays with human liver tissue samples.

Results

Through the intersection of WGCNA, differentially expressed genes, and DRGs, two key DE-DRGs (DSTN and MYL6) were identified. Immune infiltration analysis indicated a higher proportion of macrophages, T cells, and resting dendritic cells in NAFLD compared to control liver samples. Based on the key DE-DRGs, Two disulfidptosis clusters were defined in GSE126848. Cluster 1, with higher expression of the key DE-DRGs, exhibited increased immune infiltration abundance and was closely associated with oxidative stress and immune regulation compared to cluster 2. High-resolution analysis of mononuclear phagocytes highlighted the potential role of MYL6 in intrahepatic M1 phenotype Kupffer cells in NAFLD patients. Our transcriptome data revealed that the expression levels of the majority of DRGs were significantly increased in NAFLD patients. NAFLD patients exhibit elevated MYL6 correlating with inflammation, oxidative stress, and disease severity, offering promising diagnostic specificity.

Conclusion

This comprehensive study provides evidence for the association between NAFLD and disulfidptosis, identifying potential target genes and pathways in NAFLD. The identification of MYL6 as a possible treatment target for NAFLD provided a novel understanding of the disease's development.

Effective antibacterial agents in modern wound dressings: a review

Wound infections are a significant concern in healthcare, leading to long healing times. Traditional approaches for managing wound infections rely heavily on systemic antibiotics, which are associated with the emergence of antibiotic-resistant bacteria. Therefore, the development of alternative antibacterial materials for wound care has gained considerable attention. In today's world, new generations of wound dressing are commonly used to heal wounds. These new dressings keep the wound and the area around it moist to improve wound healing. However, this moist environment can also foster an environment that is favorable for the growth of bacteria. Excessive antibiotic use poses a significant threat to human health and causes bacterial resistance, so new-generation wound dressings must be designed and developed to reduce the risk of infection. Wound dressings using antimicrobial compounds minimize wound bacterial colonization, making them the best way to avoid open wound infection. We aim to provide readers with a comprehensive understanding of the latest advancements in antibacterial materials for wound management.

Identification and validation of potential diagnostic signature and immune cell infiltration for HIRI based on cuproptosis-related genes through bioinformatics analysis and machine learning

Background and aims

Cuproptosis has emerged as a significant contributor in the progression of various diseases. This study aimed to assess the potential impact of cuproptosis-related genes (CRGs) on the development of hepatic ischemia and reperfusion injury (HIRI).

Methods

The datasets related to HIRI were sourced from the Gene Expression Omnibus database. The comparative analysis of differential gene expression involving CRGs was performed between HIRI and normal liver samples. Correlation analysis, function enrichment analyses, and protein-protein interactions were employed to understand the interactions and roles of these genes. Machine learning techniques were used to identify hub genes. Additionally, differences in immune cell infiltration between HIRI patients and controls were analyzed. Quantitative real-time PCR and western blotting were used to verify the expression of the hub genes.

Results

Seventy-five HIRI and 80 control samples from three databases were included in the bioinformatics analysis. Three hub CRGs (NLRP3, ATP7B and NFE2L2) were identified using three machine learning models. Diagnostic accuracy was assessed using a receiver operating characteristic (ROC) curve for the hub genes, which yielded an area under the ROC curve (AUC) of 0.832. Remarkably, in the validation datasets GSE15480 and GSE228782, the three hub genes had AUC reached 0.904. Additional analyses, including nomograms, decision curves, and calibration curves, supported their predictive power for diagnosis. Enrichment analyses indicated the involvement of these genes in multiple pathways associated with HIRI progression. Comparative assessments using CIBERSORT and gene set enrichment analysis suggested elevated expression of these hub genes in activated dendritic cells, neutrophils, activated CD4 memory T cells, and activated mast cells in HIRI samples versus controls. A ceRNA network underscored a complex regulatory interplay among genes. The genes mRNA and protein levels were also verified in HIRI-affected mouse liver tissues.

Conclusion

Our findings have provided a comprehensive understanding of the association between cuproptosis and HIRI, establishing a promising diagnostic pattern and identifying latent therapeutic targets for HIRI treatment. Additionally, our study offers novel insights to delve deeper into the underlying mechanisms of HIRI.

Cow placenta extract ameliorates d-galactose-induced liver damage by regulating BAX/CASP3 and p53/p21/p16 pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Placenta is a kind of traditional Chinese medicine, known as "Ziheche", which has the function of tonifying qi and blood, nourishing liver and kidney. Placenta extract (PE) has been used for delaying organismal aging and treating various liver diseases. Cow placenta is a rich natural resource with large mass. Its composition is similar to that of human placenta, but it has not been effectively utilized. However, little is known about the effect of CPE on the liver of aging mice.

AIM OF THE STUDY

The aim of this study is to explore the protective effect and mechanism of CPE on the liver of d-galactose (D-gal) induced aging mice.

MATERIALS AND METHODS

Statistical methods were used to calculate mouse body weight and liver index. Hematoxylin-eosin (H&E) and transmission electron microscopy (TEM) were used to detect the morphological structure of the liver. Automatic biochemical analyzer was used to measure serum biochemical indicators. Three special staining methods were used to observe hepatocytes apoptosis, senescence and proliferation respectively. Relative kits were used to detect oxidative, inflammatory, and aging markers in the liver. Finally, real-time quantitative polymerase chain reaction and western-blot were used to detect aging related signaling pathways.

RESULTS

CPE significantly improved the morphological damage and dysfunction of liver, restored the activities of liver enzymes in serum, and alleviated liver oxidative stress and inflammatory response in D-gal induced aging mice. Furthermore, CPE inhibited hepatocyte apoptosis and senescence, and promoted hepatocyte proliferation by regulating BAX/CASP3 and p53/p21/p16 signaling pathways, ultimately reduced the effects of aging on the liver.

CONCLUSION

CPE effectively ameliorated the impact of aging on the liver by inhibiting free radical production or scavenging excessive free radicals, and its mechanism is associated to the regulation of apoptosis and proliferation-related factors.

Roles of reactive oxygen species in inflammation and cancer

Reactive oxygen species (ROS) constitute a spectrum of oxygenic metabolites crucial in modulating pathological organism functions. Disruptions in ROS equilibrium span various diseases, and current insights suggest a dual role for ROS in tumorigenesis and the immune response within cancer. This review rigorously examines ROS production and its role in normal cells, elucidating the subsequent regulatory network in inflammation and cancer. Comprehensive synthesis details the documented impacts of ROS on diverse immune cells. Exploring the intricate relationship between ROS and cancer immunity, we highlight its influence on existing immunotherapies, including immune checkpoint blockade, chimeric antigen receptors, and cancer vaccines. Additionally, we underscore the promising prospects of utilizing ROS and targeting ROS modulators as novel immunotherapeutic interventions for cancer. This review discusses the complex interplay between ROS, inflammation, and tumorigenesis, emphasizing the multifaceted functions of ROS in both physiological and pathological conditions. It also underscores the potential implications of ROS in cancer immunotherapy and suggests future research directions, including the development of targeted therapies and precision oncology approaches. In summary, this review emphasizes the significance of understanding ROS-mediated mechanisms for advancing cancer therapy and developing personalized treatments.

Rivaroxaban down-regulates pyroptosis and the TLR4/NF-κB/NLRP3 signaling pathway to promote flap survival

BACKGROUND

Flap placement remains the primary method for wound repair, but postoperative ischemic flap necrosis is of major concern. This study explored whether rivaroxaban, a factor Xa inhibitor, enhanced flap survival.

METHODS

Thirty-six rats were randomly divided into control, low-dose rivaroxaban (3 mg/kg/day), and high-dose rivaroxaban (7 mg/kg/day) groups. On postoperative day 7, the flap survival rate was analyzed and the average survival area calculated. After the rats were euthanized, immunological and molecular biological techniques were employed to assess vascular regeneration, pyroptosis, and inflammation.

RESULTS

Rivaroxaban upregulated VEGF expression, in turn enhancing angiogenesis, and it downregulated IL-1β, IL-6, and TNF-α expression, thereby mitigating inflammation. The drug also suppressed TLR4, NF-κB p65, NLRP3, caspase-1, and IL-18 syntheses, thus inhibiting pyroptosis.

CONCLUSIONS

Rivaroxaban enhanced random flap survival by down-regulating the TLR4/NF-κB/NLRP3 signaling pathway to suppress pyroptosis, promoting vascular regeneration and inhibiting inflammation.

Integrated multi-omic analysis identifies fatty acid binding protein 4 as a biomarker and therapeutic target of ischemia-reperfusion injury in steatotic liver transplantation

BACKGROUND AND AIMS

Due to a lack of donor grafts, steatotic livers are used more often for liver transplantation (LT). However, steatotic donor livers are more sensitive to ischemia-reperfusion (IR) injury and have a worse prognosis after LT. Efforts to optimize steatotic liver grafts by identifying injury targets and interventions have become a hot issue.

METHODS

Mouse LT models were established, and 4D label-free proteome sequencing was performed for four groups: normal control (NC) SHAM, high-fat (HF) SHAM, NC LT, and HF LT to screen molecular targets for aggravating liver injury in steatotic LT. Expression detection of molecular targets was performed based on liver specimens from 110 donors to verify its impact on the overall survival of recipients. Pharmacological intervention using small-molecule inhibitors on an injury-related target was used to evaluate the therapeutic effect. Transcriptomics and metabolomics were performed to explore the regulatory network and further integrated bioinformatics analysis and multiplex immunofluorescence were adopted to assess the regulation of pathways and organelles.

RESULTS

HF LT group represented worse liver function compared with NC LT group, including more apoptotic hepatocytes (P < 0.01) and higher serum transaminase (P < 0.05). Proteomic results revealed that the mitochondrial membrane, endocytosis, and oxidative phosphorylation pathways were upregulated in HF LT group. Fatty acid binding protein 4 (FABP4) was identified as a hypoxia-inducible protein (fold change > 2 and P < 0.05) that sensitized mice to IR injury in steatotic LT. The overall survival of recipients using liver grafts with high expression of FABP4 was significantly worse than low expression of FABP4 (68.5 vs. 87.3%, P < 0.05). Adoption of FABP4 inhibitor could protect the steatotic liver from IR injury during transplantation, including reducing hepatocyte apoptosis, reducing serum transaminase (P < 0.05), and alleviating oxidative stress damage (P < 0.01). According to integrated transcriptomics and metabolomics analysis, cAMP signaling pathway was enriched following FABP4 inhibitor use. The activation of cAMP signaling pathway was validated. Microscopy and immunofluorescence staining results suggested that FABP4 inhibitors could regulate mitochondrial membrane homeostasis in steatotic LT.

CONCLUSIONS

FABP4 was identified as a hypoxia-inducible protein that sensitized steatotic liver grafts to IR injury. The FABP4 inhibitor, BMS-309403, could activate of cAMP signaling pathway thereby modulating mitochondrial membrane homeostasis, reducing oxidative stress injury in steatotic donors.

Exploring the Multifaceted Landscape of MASLD: A Comprehensive Synthesis of Recent Studies, from Pathophysiology to Organoids and Beyond

Non-alcoholic fatty liver disease (NAFLD) is a widespread contributor to chronic liver disease globally. A recent consensus on renaming liver disease was established, and metabolic dysfunction-associated steatotic liver disease, MASLD, was chosen as the replacement for NAFLD. The disease's range extends from the less severe MASLD, previously known as non-alcoholic fatty liver (NAFL), to the more intense metabolic dysfunction-associated steatohepatitis (MASH), previously known as non-alcoholic steatohepatitis (NASH), characterized by inflammation and apoptosis. This research project endeavors to comprehensively synthesize the most recent studies on MASLD, encompassing a wide spectrum of topics such as pathophysiology, risk factors, dietary influences, lifestyle management, genetics, epigenetics, therapeutic approaches, and the prospective trajectory of MASLD, particularly exploring its connection with organoids.

Nobiletin Ameliorates Hepatic Lipid Deposition, Oxidative Stress, and Inflammation by Mechanisms That Involve the Nrf2/NF-κB Axis in Nonalcoholic Fatty Liver Disease

Nobiletin (NOB), a flavonoid with significant antioxidant potential, holds promise for treating nonalcoholic fatty liver disease (NAFLD). In this work, we aim to assess the effects and investigate the molecular mechanisms of NOB on NAFLD. After using a methionine choline-deficient diet to induce C57BL/6J mice, as well as oleic acid to induce HepG2 and L02 cells, we administered NOB as an intervention. The results indicated that the NOB significantly ameliorated lipid deposition, oxidative stress, and inflammation in NAFLD in both models. Its mechanism may involve the Nrf2, SREBP-1c, and NF-κB signaling pathways. Furthermore, Nrf2 is not only a direct target for NOB to improve oxidative damage but also indirectly involved in lipid-lowering and anti-inflammatory processes in NAFLD. By inhibiting Nrf2, we found that the regulatory role of Nrf2 in lipid metabolism is not related to SREBP-1c but is closely associated with NF-κB in terms of inflammation. Our results suggest that Nrf2 is one of the most critical targets for NOB against NAFLD in multiple aspects.

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

BACKGROUND AND AIMS

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

METHODS AND RESULTS

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

CONCLUSIONS

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

Hepatocellular SETDB1 Regulates Hepatic Ischemia-Reperfusion Injury through Targeting Lysine Methylation of ASK1 Signal

Background: Hepatic ischemia-reperfusion injury (HIRI) stands as an unavoidable complication arising from liver surgery, profoundly intertwined with its prognosis. The role of lysine methyltransferase SET domain bifurcated 1 (SETDB1) in HIRI remains elusive, despite its confirmation as a potential therapeutic target for diverse diseases. Here, we investigated the mechanism by which SETDB1 regulated HIRI. Methods: RNA sequencing data were used to identify the expression and potential targets of SETDB1 through bioinformatics analysis. To elucidate the impact of SETDB1 on HIRI, both an in vivo model of HIRI in mice and an in vitro model of hepatocyte hypoxia/reoxygenation were established. Biochemical and histological analyses were used to investigate the influence of SETDB1 on liver damage mediated by HIRI. Chromatin immunoprecipitation and coimmunoprecipitation were implemented to explore the in-depth mechanism of SETDB1 regulating HIRI. Results: We confirmed that hepatocellular SETDB1 was up-regulated during HIRI and had a close correlation with HIRI-related inflammation and apoptosis. Moreover, inhibition of SETDB1 could mitigate HIRI-induced liver damage, inflammation, and apoptosis. Through our comprehensive mechanistic investigation, we revealed that SETDB1 interacts with apoptosis-signal-regulating kinase 1 (ASK1) and facilitates the methylation of its lysine residues. Inhibition of SETDB1 resulted in reduced phosphorylation of ASK1, leading to a marked suppression of downstream c-Jun N-terminal kinase (JNK)/p38 signaling pathway activation. The therapeutic effect on inflammation and apoptosis achieved through SETDB1 inhibition was nullified by the restoration of JNK/p38 signaling activation through ASK1 overexpression. Conclusions: The findings from our study indicate that SETDB1 mediates lysine methylation of ASK1 and modulates the activation of the ASK1-JNK/p38 pathway, thus involved in HIRI-induced inflammation and apoptosis. These results suggest that SETDB1 holds promise as a potential therapeutic target for mitigating HIRI.

Activation of NLRP3 Inflammasome via Drp1 Overexpression in Kupffer Cells Aggravates Ischemia-reperfusion Injury in Hepatic Steatosis

Background and Aims

Donors with fatty livers are considered to address the shortage of livers for transplantation, but those livers are particularly sensitive to ischemia-reperfusion injury (IRI), and an increased incidence of graft failure is observed. Kupffer cells account for 20-35% of liver nonparenchymal cells, and have been shown to participate in the process of IRI and inflammatory reactions of hepatic steatosis. NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) is an intracellular sensor activated by Kupffer cells to promote generation and participates in IRI. Dynamics-associated protein 1 (Drp1) is one of the main proteins regulating mitochondrial division and exacerbates IRI by affecting mitochondrial dynamics. The mechanism of interaction of Kupffer cells with Drp1 and NLRP3 to aggravate IRI has not been clarified.

Methods

A mouse model of hepatic steatosis was established by feeding the mice with a high-fat diet. In vitro experiments were performed using AML12 normal mouse liver cells and RAW264.7 mononuclear macrophage cells cultured in medium with palmitate and oleic acid. Western blotting and immunohistochemical (IHC) staining were used to detect the expression of NLRPP3 and Drp1 in IRI in the control and high-fat diet groups. The expression of F4/80+ cells during IRI in hepatic steatosis was verified by IHC staining, and the role of NLRPP3 and Drp1 in Kupffer-cell mediated IRI was investigated by targeting Drp-1 inhibition.

Results

Drp1 and NLRP3 expression was increased during IRI in hepatic steatosis, and the expression of Drp1 and NLRP3 were decreased after the elimination of Kupffer cells. That indicated Kupffer cells were involved in the process of IRI in hepatic steatosis through the action of Drp1 and NLRP3. After Drp1 inhibition, liver function was restored and NLRP3 expression level was reduced.

Conclusions

Kupffer cells aggravated IRI in hepatic steatosis via NLRP3 and Drp1. Drp1 inhibitors might be useful as specific therapeutics to alleviate IRI in hepatic steatosis and may have promise in case of liver donor shortage.

The Coumarin-Derivative Esculetin Protects against Lipotoxicity in Primary Rat Hepatocytes via Attenuating JNK-Mediated Oxidative Stress and Attenuates Free Fatty Acid-Induced Lipid Accumulation

Coumarin derivates have been proposed as a potential treatment for metabolic-dysfunction-associated fatty liver disease (MAFLD). However, the mechanisms underlying their beneficial effects remain unclear. In the present study, we explored the potential of the coumarin derivate esculetin in MAFLD, focusing on hepatocyte lipotoxicity and lipid accumulation. Primary cultures of rat hepatocytes were exposed to palmitic acid (PA) and palmitic acid plus oleic acid (OA/PA) as models of lipotoxicity and lipid accumulation, respectively. Esculetin significantly reduced oxidative stress in PA-treated hepatocytes, as shown by decreased total reactive oxygen species (ROS) and mitochondrial superoxide production and elevated expression of antioxidant genes, including Nrf2 and Gpx1. In addition, esculetin protects against PA-induced necrosis. Esculetin also improved lipid metabolism in primary hepatocytes exposed to nonlipotoxic OA/PA by decreasing the expression of the lipogenesis-related gene Srebp1c and increasing the expression of the fatty acid β-oxidation-related gene Ppar-α. Moreover, esculetin attenuated lipid accumulation in OA/PA-treated hepatocytes. The protective effects of esculetin against lipotoxicity and lipid accumulation were shown to be dependent on the inhibition of JNK and the activation of AMPK, respectively. We conclude that esculetin is a promising compound to target lipotoxicity and lipid accumulation in the treatment of MAFLD.

Skimmianine attenuates liver ischemia/reperfusion injury by regulating PI3K-AKT signaling pathway-mediated inflammation, apoptosis and oxidative stress

Liver ischemia/reperfusion (I/R) injury is a common injury after liver transplantation and hepatectomy. Skimmianine (Ski) has antibacterial, antiviral pharmacological effects. However, it is not clear whether Ski has a protective effect against liver I/R injury. In the present study, we established a mouse liver I/R model and an AML12 cell hypoxia-reoxygenation (H/R) model, both pretreated with different concentrations of Ski. Serum transaminase levels, necrotic liver area, cell viability, inflammatory factors, oxidative stress and apoptosis-related levels were measured to assess the protective effect of Ski against liver I/R injury. Western blotting was used to detect apoptosis-related proteins and PI3K-AKT pathway-related proteins. Mice and cells were also treated with PI3K inhibitor LY294002 to assess changes in indicators of liver injury. The results showed that Ski significantly reduced transaminase levels, liver necrosis area, oxidative stress, and apoptosis levels in mice with I/R. Ski also inhibited cell injury and apoptosis after H/R. Moreover, Ski activated phosphorylation of PI3K-AKT pathway-related proteins after liver I/R and cell H/R. Importantly, the PI3K inhibitor LY294002 effectively reversed the alleviation of I/R injury caused by Ski. These results confirm that Ski exerts a protective effect against liver I/R injury through activation of the PI3K-AKT pathway.

Chronic inflammation and the hallmarks of aging

BACKGROUND

Recently, the hallmarks of aging were updated to include dysbiosis, disabled macroautophagy, and chronic inflammation. In particular, the low-grade chronic inflammation during aging, without overt infection, is defined as "inflammaging," which is associated with increased morbidity and mortality in the aging population. Emerging evidence suggests a bidirectional and cyclical relationship between chronic inflammation and the development of age-related conditions, such as cardiovascular diseases, neurodegeneration, cancer, and frailty. How the crosstalk between chronic inflammation and other hallmarks of aging underlies biological mechanisms of aging and age-related disease is thus of particular interest to the current geroscience research.

SCOPE OF REVIEW

This review integrates the cellular and molecular mechanisms of age-associated chronic inflammation with the other eleven hallmarks of aging. Extra discussion is dedicated to the hallmark of "altered nutrient sensing," given the scope of Molecular Metabolism. The deregulation of hallmark processes during aging disrupts the delicate balance between pro-inflammatory and anti-inflammatory signaling, leading to a persistent inflammatory state. The resultant chronic inflammation, in turn, further aggravates the dysfunction of each hallmark, thereby driving the progression of aging and age-related diseases.

MAIN CONCLUSIONS

The crosstalk between chronic inflammation and other hallmarks of aging results in a vicious cycle that exacerbates the decline in cellular functions and promotes aging. Understanding this complex interplay will provide new insights into the mechanisms of aging and the development of potential anti-aging interventions. Given their interconnectedness and ability to accentuate the primary elements of aging, drivers of chronic inflammation may be an ideal target with high translational potential to address the pathological conditions associated with aging.

New therapeutic concepts against ischemia-reperfusion injury in organ transplantation

INTRODUCTION

Ischemia-reperfusion injury (IRI) involves a positive amplification feedback loop that stimulates innate immune-driven tissue damage associated with organ procurement from deceased donors and during transplantation surgery. As our appreciation of its basic immune mechanisms has improved in recent years, translating putative biomarkers into therapeutic interventions in clinical transplantation remains challenging.

AREAS COVERED

This review presents advances in translational/clinical studies targeting immune responses to reactive oxygen species in IRI-stressed solid organ transplants, especially livers. Here we focus on novel concepts to rejuvenate suboptimal donor organs and improve transplant function using pharmacologic and machine perfusion (MP) strategies. Cellular damage induced by cold ischemia/warm reperfusion and the latest mechanistic insights into the microenvironment's role that leads to reperfusion-induced sterile inflammation is critically discussed.

EXPERT OPINION

Efforts to improve clinical outcomes and increase the donor organ pool will depend on improving donor management and our better appreciation of the complex mechanisms encompassing organ IRI that govern the innate-adaptive immune interface triggered in the peritransplant period and subsequent allo-Ag challenge. Computational techniques and deep machine learning incorporating the vast cellular and molecular mechanisms will predict which peri-transplant signals and immune interactions are essential for improving access to the long-term function of life-saving transplants.

Oxidative Stress and MicroRNAs in Endothelial Cells under Metabolic Disorders

Reactive oxygen species (ROS) are radical oxygen intermediates that serve as important second messengers in signal transduction. However, when the accumulation of these molecules exceeds the buffering capacity of antioxidant enzymes, oxidative stress and endothelial cell (EC) dysfunction occur. EC dysfunction shifts the vascular system into a pro-coagulative, proinflammatory state, thereby increasing the risk of developing cardiovascular (CV) diseases and metabolic disorders. Studies have turned to the investigation of microRNA treatment for CV risk factors, as these post-transcription regulators are known to co-regulate ROS. In this review, we will discuss ROS pathways and generation, normal endothelial cell physiology and ROS-induced dysfunction, and the current knowledge of common metabolic disorders and their connection to oxidative stress. Therapeutic strategies based on microRNAs in response to oxidative stress and microRNA's regulatory roles in controlling ROS will also be explored. It is important to gain an in-depth comprehension of the mechanisms generating ROS and how manipulating these enzymatic byproducts can protect endothelial cell function from oxidative stress and prevent the development of vascular disorders.

Effect and mechanism of reactive oxygen species-mediated NOD-like receptor family pyrin domain-containing 3 inflammasome activation in hepatic alveolar echinococcosis

BACKGROUND

The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is a significant component of the innate immune system that plays a vital role in the development of various parasitic diseases. However, its role in hepatic alveolar echinococcosis (HAE) remains unclear.

AIM

To investigate the NLRP3 inflammasome and its mechanism of activation in HAE.

METHODS

We assessed the expression of NLRP3, caspase-1, interleukin (IL)-1β, and IL-18 in the marginal zone and corresponding normal liver of 60 patients with HAE. A rat model of HAE was employed to investigate the role of the NLRP3 inflammasome in the marginal zone of HAE. Transwell experiments were conducted to investigate the effect of Echinococcus multilocularis (E. multilocularis) in stimulating Kupffer cells and hepatocytes. Furthermore, immunohistochemistry, Western blotting, and enzyme-linked immunosorbent assay were used to evaluate NLRP3, caspase-1, IL-1β, and IL-18 expression; flow cytometry was used to detect apoptosis and reactive oxygen species (ROS).

RESULTS

NLRP3 inflammasome activation was significantly associated with ROS. Inhibition of ROS production decreased NLRP3-caspase-1-IL-1β pathway activation and mitigated hepatocyte damage and inflammation.

CONCLUSION

E. multilocularis induces hepatocyte damage and inflammation by activating the ROS-mediated NLRP3-caspase-1-IL-1β pathway in Kupffer cells, indicating that ROS may serve as a potential target for the treatment of HAE.

MicroRNA-146a Improved Acute Lung Injury Induced by hepatic Ischemia-reperfusion Injury by Inhibiting PRDX1

Hepatic ischemia-reperfusion injury (HIRI)-induced acute lung injury (ALI) is characterized by high incidence and poor prognosis. The regulatory role of microRNA-146a (miR-146a) in HIRI has been reported, but if miR-146a could affect the progression of HIRI-induced ALI has not been reported. The mice HIRI model was established by ligating left hepatic portal vein and hepatic artery for 60 minutes and then treating with reperfusion for 4 hours. Hypoxia-reoxygenation (HR) was performed to establish cell model. The binding site between miR-146a and Peroxidase 1 (PRDX1) was predicted and validated. The levels of inflammation factors and redox markers were detected with commercial kits. Significant lower expression of miR-146a and higher expression of PRDX1 in HIRI animal model were observed. miR-146a inhibited the liver injury after HIRI induction through targeting PRDX1. miR-146a inhibited the lung injury caused by HIRI via regulating PRDX1. The inhibition of cell apoptosis and inflammation factors by miR-146a were reversed by pcDNA-PRDX1. This research demonstrated that miR-146a improved ALI caused by HIRI by inhibiting apoptosis, inflammation, oxidative condition through targeting PRDX1. This study might provide a novel thought for the prevention and treatment of ALI caused by HIRI by regulating miR-146a/PRDX1 axis.

ADSCs-exo attenuates hepatic ischemia-reperfusion injury after hepatectomy by inhibiting endoplasmic reticulum stress and inflammation

Hepatic ischemia-reperfusion (I/R) injury commonly occurs during liver surgery. Exosomes from adipose-derived stem cells (ADSCs-exo) induce a hepatoprotective effect during hepatic I/R injury. This study aimed to investigate the possible mechanism by which ADSCs-exo attenuates hepatic I/R injury in rats. Rats were randomly divided into four groups: Sham, I30R + PH, ADSCs, and ADSCs-exo groups. Liver tissues were collected immediately after 24 h of reperfusion for further analyses. The content of inflammatory factors in liver tissue was detected using enzyme-linked immunosorbent assay. The pathological changes in liver tissue were analyzed using HE staining. Transmission electron microscopy was used to visualize the ultrastructural changes of hepatocytes. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot analysis were used to detect the expression of endoplasmic reticulum stress (ERS)-related genes and proteins. Liver histomorphology and hepatocyte ultrastructure changes improved after ADSCs-exo treatment. Moreover, ADSCs-exo treatment significantly downregulated tumor necrosis factor-α, interleukin-1β (IL-1β), and IL-6 levels while upregulating IL-10 levels. Western blot analysis suggested that the protein expressions of GRP78, p-PERK, p-eIF2α, p-IRE1α, XBP1s, ATF-6, ATF-4, CHOP, p-JNK, cleaved-Caspase-3, cleaved Caspase-9, and cleaved Caspase-12 significantly decreased after ADSCs-exo treatment. RT-qPCR results demonstrated that mRNA expression of GRP78, IRE1α, XBP1, ATF-6, ATF-4, CHOP, JNK, Caspase-3, Caspase-9, and Caspase-12 markedly reduced after ADSCs-exo treatment. In conclusion, ADSCs-exo protects against hepatic I/R injury after hepatectomy by inhibiting ERS and inflammation. Therefore, ADSCs-exo can be considered as a viable option for the treatment of hepatic I/R injury.

The Role of the NLRP3 Inflammasome and Programmed Cell Death in Acute Liver Injury

Acute liver injury (ALI) is a globally important public health issue that, when severe, rapidly progresses to acute liver failure, seriously compromising the life safety of patients. The pathogenesis of ALI is defined by massive cell death in the liver, which triggers a cascade of immune responses. Studies have shown that the aberrant activation of the nod-like receptor protein 3 (NLRP3) inflammasome plays an important role in various types of ALI and that the activation of the NLRP3 inflammasome causes various types of programmed cell death (PCD), and these cell death effectors can in turn regulate NLRP3 inflammasome activation. This indicates that NLRP3 inflammasome activation is inextricably linked to PCD. In this review, we summarize the role of NLRP3 inflammasome activation and PCD in various types of ALI (APAP, liver ischemia reperfusion, CCl₄, alcohol, Con A, and LPS/D-GalN induced ALI) and analyze the underlying mechanisms to provide references for future relevant studies.

Health-Promoting Activities and Associated Mechanisms of Polygonati Rhizoma Polysaccharides

Polygonati Rhizoma, a typical homology of medicine and food, possesses remarkable anti-fatigue, anti-aging, metabolic regulatory, immunomodulatory, anti-inflammatory, neuroprotective, anti-diabetes, and anti-cancer effects. Among bioactive phytochemicals in Polygonati Rhizoma, polysaccharides play important roles in the health-promoting activities through the mechanisms mentioned above and potential synergistic effects with other bioactives. In this review, we briefly introduce the updated biosynthesis of polysaccharides, the purification method, the structure characterization, and food applications, and discuss in detail the biological activities of Polygonati Rhizoma polysaccharides and associated mechanisms, aiming at broadening the usage of Polygonati Rhizoma as functional food and medicine.

P-21 Activated Kinases in Liver Disorders

The p21 Activated Kinases (PAKs) are serine threonine kinases and play important roles in many biological processes, including cell growth, survival, cytoskeletal organization, migration, and morphology. Recently, PAKs have emerged in the process of liver disorders, including liver cancer, hepatic ischemia-reperfusion injury, hepatitis, and liver fibrosis, owing to their effects in multiple signaling pathways in various cell types. Activation of PAKs promotes liver cancer growth and metastasis and contributes to the resistance of liver cancer to radiotherapy and chemotherapy, leading to poor survival of patients. PAKs also play important roles in the development and progression of hepatitis and other pathological processes of the liver such as fibrosis and ischemia-reperfusion injury. In this review, we have summarized the currently available studies about the role of PAKs in liver disorders and the mechanisms involved, and further explored the potential therapeutic application of PAK inhibitors in liver disorders, with the aim to provide a comprehensive overview on current progress and perspectives of PAKs in liver disorders.

Protective Efficiency Comparison of Direct and Remote Ischemic Preconditioning on Ischemia Reperfusion Injury of the Liver in Patients Undergoing Partial Hepatectomy

Objective

Ischemia reperfusion injury greatly damages liver function and deteriorates the prognosis of patients undergoing partial hepatectomy. This study is to compare the protective efficiency of direct and remote ischemic preconditioning (DIPC and RIPC) on ischemia reperfusion injury of the liver in patients undergoing partial hepatectomy.

Methods

90 patients scheduled for partial hepatectomy were enrolled and randomly divided into control (n = 30), DIPC (n = 30), and RIPC (n = 30) groups. Baseline and surgery characteristics were collected, and ischemic preconditioning methods were carried out. Intraoperative hemodynamics, liver function and liver reserve capacity, oxidative stress, and inflammatory responses were measured, and the incidence of postoperative adverse reactions was calculated finally.

Results

10 patients were excluded from the study, and finally, the eligible patients in three groups were 27, 28, and 25, separately. No significant differences were observed in baseline and surgery characteristics among the three groups. SBP and DBP were significantly higher after hepatic portal vein occlusion while they were significantly lower after surgery in the DIPC and RIPC groups compared with that in the control group, SBP and DBP were of great fluctuation at different time points in the control group while they showed much more stabilization in the DIPC and RIPC groups. ALT, AST, and TBIL were significantly decreased on days 1, 3, and 5 after surgery, and ICG R15 was significantly decreased while ICG K value and EHBF were significantly increased on day 1 after surgery in the DIPC and RIPC groups compared with that in the control group. Moreover, antioxidant enzyme SOD was increased, and inflammatory factors TNF-α and IL-1β were decreased 24 hours after surgery in the DIPC and RIPC groups compared with that in the control group. DIPC and RIPC also decreased hospital stays and the incidence of nausea, vomiting, and hypertension.

Conclusion

DIPC and RIPC both alleviated ischemia reperfusion injury of the liver and reduced perioperative complications with similar protective efficiency in patients undergoing partial hepatectomy.

Vitamin D Receptor Regulates Autophagy to Inhibit Apoptosis and Promote Proliferation in Hepatocyte Injury

BACKGROUND

Oxidative stress is an important mechanism in liver ischemia/reperfusion (I/R) injury. Hepatocyte apoptosis and proliferation occur in parallel with liver I/R injury, and the degree of apoptosis and proliferation determines the effects on hepatocytes. Vitamin D receptor (VDR) can lessen liver I/R injury, but previous studies focused mostly on inflammation and immunity.

METHODS

H₂O₂ was used to induce hepatocyte injury. Before treatment with H₂O₂, Hep-3B cells were pretreated with paricalcitol (PC) and siRNA-VDR. Rapamycin and chloroquine were also applied in the study.

RESULTS

The number of apoptotic cells was measured with an annexin V (AV) -fluorescein isothiocyanate apoptosis detection kit. Expression of proteins was measured by western blotting. As compared with the H₂O₂+Hep-3B group, levels of AV/PI, cleaved caspase-3, and p62 were lower, and expression levels of Bcl-2, proliferating cell nuclear antigen, and VDR were higher, in the PC+H₂O₂+Hep-3B group. When the VDR gene was silenced by siRNA-VDR in the siRNA-VDR+H₂O₂+Hep-3B group, expressions of AV/PI, cleaved caspase-3, and p62 were upregulated, and expressions of Bcl-2, proliferating cell nuclear antigen, and VDR were downregulated, as compared with values for the siRNA-NC+H₂O₂+Hep-3B group. Treatment with rapamycin or chloroquine partially reversed the effect of PC and siRNA-VDR on apoptosis and proliferation.

CONCLUSIONS

VDR mediates hepatocyte apoptosis and proliferation through autophagy.

Role of macrophage scavenger receptor MSR1 in the progression of non-alcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is the progressive form of nonalcoholic fatty liver disease (NAFLD), and the dysregulation of lipid metabolism and oxidative stress are the typical features. Subsequent dyslipidemia and oxygen radical production may render the formation of modified lipids. Macrophage scavenger receptor 1 (MSR1) is responsible for the uptake of modified lipoprotein and is one of the key molecules in atherosclerosis. However, the unrestricted uptake of modified lipoproteins by MSR1 and the formation of cholesterol-rich foamy macrophages also can be observed in NASH patients and mouse models. In this review, we highlight the dysregulation of lipid metabolism and oxidative stress in NASH, the alteration of MSR1 expression in physiological and pathological conditions, the formation of modified lipoproteins, and the role of MSR1 on macrophage foaming and NASH development and progression.

Role of Oxidative Stress and Lipid Peroxidation in the Pathophysiology of NAFLD

Non-alcoholic fatty liver disease (NAFLD) is characterised by an excess of hepatic fat that can progress to steatohepatitis, fibrosis, cirrhosis and hepatocarcinoma. The imbalance between lipid uptake/lipogenesis and lipid oxidation/secretion in the liver is a major feature of NAFLD. Given the lack of a non-invasive and reliable methods for the diagnosis of non-alcoholic steatohepatitis (NASH), it is important to find serum markers that are capable of discriminating or defining patients with this stage of NASH. Blood samples were obtained from 152 Caucasian subjects with biopsy-proven NAFLD due to persistently elevated liver enzyme levels. Metabolites representative of oxidative stress were assessed. The findings derived from this work revealed that NAFLD patients with a NASH score of ≥ 4 showed significantly higher levels of lipid peroxidation (LPO). Indeed, LPO levels above the optimal operating point (OOP) of 315.39 μM are an independent risk factor for presenting a NASH score of ≥ 4 (OR: 4.71; 95% CI: 1.68−13.19; p = 0.003). The area under the curve (AUC = 0.81, 95% CI = 0.73−0.89, p < 0.001) shows a good discrimination ability of the model. Therefore, understanding the molecular mechanisms underlying the basal inflammation present in these patients is postulated as a possible source of biomarkers and therapeutic targets in NASH.

Hepatic macrophage mediated immune response in liver steatosis driven carcinogenesis

Obesity confers an independent risk for carcinogenesis. Classically viewed as a genetic disease, owing to the discovery of tumor suppressors and oncogenes, genetic events alone are not sufficient to explain the progression and development of cancers. Tumor development is often associated with metabolic and immunological changes. In particular, obesity is found to significantly increase the mortality rate of liver cancer. As its role is not defined, a fundamental question is whether and how metabolic changes drive the development of cancer. In this review, we will dissect the current literature demonstrating that liver lipid dysfunction is a critical component driving the progression of cancer. We will discuss the involvement of inflammation in lipid dysfunction driven liver cancer development with a focus on the involvement of liver macrophages. We will first discuss the association of steatosis with liver cancer. This will be followed with a literature summary demonstrating the importance of inflammation and particularly macrophages in the progression of liver steatosis and highlighting the evidence that macrophages and macrophage produced inflammatory mediators are critical for liver cancer development. We will then discuss the specific inflammatory mediators and their roles in steatosis driven liver cancer development. Finally, we will summarize the molecular pattern (PAMP and DAMP) as well as lipid particle signals that are involved in the activation, infiltration and reprogramming of liver macrophages. We will also discuss some of the therapies that may interfere with lipid metabolism and also affect liver cancer development.

Histopathological Evaluation of Annona muricata in TAA-Induced Liver Injury in Rats

This research in vivo assessed the impact of the ethanolic extract of Annona muricata (A. muricata) on the histopathology, immunohistochemistry, and biochemistry of thioacetamide (TAA)-induced liver cirrhosis in Sprague Dawley rats. The rats, gavaged precisely with two doses of A. muricata (250 mg/kg and 500 mg/kg) with TAA, presented a substantial reduction in the liver index and hepatocyte propagation, with much lower cell injury. These groups showed meaningfully down-regulated proliferating cell nuclear antigen (PCNA) in the liver and spleen, α-smooth muscle actin (α-SMA), and transforming growth factor-beta 1 (TGF-β1) in liver parenchymal tissue. The liver homogenate displayed enhanced antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT) activity, along with a decrease in malondialdehyde (MDA) levels. The serum levels of bilirubin, total protein, albumin, and liver enzymes alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were returned to normal and were similar to that of the normal control and silymarin with TAA-treated groups. Oral acute toxicity revealed no evidence of any toxic symbols or mortality in rats, indicating the safety of A. muricata. Therefore, the normal microanatomy of hepatocytes, the clampdown of PCNA, α-SMA, TGF-β, improved antioxidant enzymes (SOD and CAT), and condensed MDA with repairs of liver biomarkers validate the hepatoprotective effect of A. muricata.