Decreased Hepatocyte Autophagy Leads to Synergistic IL-1β and TNF Mouse Liver Injury and Inflammation

Role of formyl peptide receptor 2 in steatosis of L02 cells exposed to Mono-(2-ethylhexyl) phthalate

Mono-(2-ethylhexyl) phthalate (MEHP) can accumulate in the liver and then lead to hepatic steatosis, while the underlying mechanism remains unclear. Inflammation plays an important role in the disorder of hepatic lipid metabolism. This study aims to clarify the role of the inflammatory response mediated by formyl peptide receptor 2 (FPR2) in steatosis of L02 cells exposed to MEHP. L02 cells were exposed to MEHP of different concentrations and different time. A steatosis model of L02 cells was induced with oleic acid and the cells were exposed to MEHP simultaneously. In addition, L02 cells were incubated with FPR2 antagonist and then exposed to MEHP. Lipid accumulation was determined by oil red O staining and extraction assay. The indicators related to lipid metabolism and inflammatory response were measured with appropriate kits. The relative expression levels of FPR2 and its ligand were determined by Western blot, and the interaction of them was detected by co-immunoprecipitation. As a result, MEHP exposure could promote the occurrence and progression of steatosis and the secretion of chemokines and inflammatory factors in L02 cells. MEHP could also affect the expression and activation of FPR2 and the secretion of FPR2 ligands. In addition, the promotion effect of MEHP on the secretion of total cholesterol and interleukin 1β in L02 cells could be significantly inhibited by the FPR2 antagonist. We concluded that FPR2 might affect the promotion effect of MEHP on steatosis of L02 cells by mediating inflammatory response.

Aging and Autophagy: Roles in Musculoskeletal System Injury

Aging is a multifactorial process that ultimately leads to a decline in physiological function and a consequent reduction in the health span, and quality of life in elderly population. In musculoskeletal diseases, aging is often associated with a gradual loss of skeletal muscle mass and strength, resulting in reduced functional capacity and an increased risk of chronic metabolic diseases, leading to impaired function and increased mortality. Autophagy is a highly conserved physiological process by which cells, under the regulation of autophagy-related genes, degrade their own organelles and large molecules by lysosomal degradation. This process is unique to eukaryotic cells and is a strict regulator of homeostasis, the maintenance of energy and substance balance. Autophagy plays an important role in a wide range of physiological and pathological processes such as cell homeostasis, aging, immunity, tumorigenesis and neurodegenerative diseases. On the one hand, under mild stress conditions, autophagy mediates the restoration of homeostasis and proliferation, reduction of the rate of aging and delay of the aging process. On the other hand, under more intense stress conditions, an inadequate suppression of autophagy can lead to cellular aging. Conversely, autophagy activity decreases during aging. Due to the interrelationship between aging and autophagy, limited literature exists on this topic. Therefore, the objective of this review is to summarize the current concepts on aging and autophagy in the musculoskeletal system. The aim is to better understand the mechanisms of age-related changes in bone, joint and muscle, as well as the interaction relationship between autophagy and aging. Its goal is to provide a comprehensive perspective for the improvement of diseases of the musculoskeletal system.

Sialyltransferase ST3GAL6 silencing reduces α2,3-sialylated glycans to regulate autophagy by decreasing HSPB8-BAG3 in the brain with hepatic encephalopathy

End-stage liver diseases, such as cirrhosis and liver cancer caused by hepatitis B, are often combined with hepatic encephalopathy (HE); ammonia poisoning is posited as one of its main pathogenesis mechanisms. Ammonia is closely related to autophagy, but the molecular mechanism of ammonia's regulatory effect on autophagy in HE remains unclear. Sialylation is an essential form of glycosylation. In the nervous system, abnormal sialylation affects various physiological processes, such as neural development and synapse formation. ST3 β‍-galactoside α2,‍3-sialyltransferase 6 (ST3GAL6) is one of the significant glycosyltransferases responsible for adding α2,3-linked sialic acid to substrates and generating glycan structures. We found that the expression of ST3GAL6 was upregulated in the brains of mice with HE and in astrocytes after ammonia induction, and the expression levels of α2,3-sialylated glycans and autophagy-related proteins microtubule-associated protein light chain 3 (LC3) and Beclin-1 were upregulated in ammonia-induced astrocytes. These findings suggest that ST3GAL6 is related to autophagy in HE. Therefore, we aimed to determine the regulatory relationship between ST3GAL6 and autophagy. We found that silencing ST3GAL6 and blocking or degrading α2,3-sialylated glycans by way of Maackia amurensis lectin-II (MAL-II) and neuraminidase can inhibit autophagy. In addition, silencing the expression of ST3GAL6 can downregulate the expression of heat shock protein β8 (HSPB8) and Bcl2-associated athanogene 3 (BAG3). Notably, the overexpression of HSPB8 partially restored the reduced autophagy levels caused by silencing ST3GAL6 expression. Our results indicate that ST3GAL6 regulates autophagy through the HSPB8-BAG3 complex.

Litchi pulp-derived gamma-aminobutyric acid (GABA) extract counteracts liver inflammation induced by litchi thaumatin-like protein

Gamma-aminobutyric acid (GABA) is the predominant amino acid in litchi pulp, known for its neuroregulatory effects and anti-inflammatory properties. Although previous research has highlighted the pro-inflammatory characteristics of litchi thaumatin-like protein (LcTLP), interplay between GABA and LcTLP in relation to inflammation remains unclear. This study aims to explore the hepatoprotective effects of the litchi pulp-derived GABA extract (LGE) against LcTLP-induced liver inflammation in mice and LO2 cells. In vivo experiments demonstrated that LGE significantly reduced the levels of aspartate transaminase and alanine transaminase, and protected the liver against infiltration of CD4+ and CD8+ T cells and histological injury induced by LcTLP. Pro-inflammatory cytokines including interleukin-6, interleukin-1β, and tumor necrosis factor-α were also diminished by LGE. The LGE appeared to modulate the mitogen-activated protein kinase (MAPK) signaling pathway to exert its anti-inflammatory effects, as evidenced by a reduction of 47%, 35%, and 31% in phosphorylated p38, JNK, and ERK expressions, respectively, in the liver of the high-dose LGE group. Additionally, LGE effectively improved the translocation of gut microbiota by modulating its microbiological composition and abundance. In vitro studies have shown that LGE effectively counteracts the increase in reactive oxygen species, calcium ions, and pro-inflammatory cytokines induced by LcTLP. These findings may offer new perspectives on the health benefits and safety of litchi consumption.

TRPM2-dependent autophagy inhibition exacerbates oxidative stress-induced CXCL16 secretion by keratinocytes in vitiligo

Vitiligo is a depigmented skin disease due to the destruction of melanocytes. Under oxidative stress, keratinocyte-derived chemokine C-X-C motif ligand 16 (CXCL16) plays a critical role in recruiting CD8+ T cells, which kill melanocytes. Autophagy serves as a protective cell survival mechanism and impairment of autophagy has been linked to increased secretion of the proinflammatory cytokines. However, the role of autophagy in the secretion of CXCL16 under oxidative stress has not been investigated. Herein, we initially found that autophagy was suppressed in both keratinocytes of vitiligo lesions and keratinocytes exposed to oxidative stress in vitro. Autophagy inhibition also promoted CXCL16 secretion. Furthermore, upregulated transient receptor potential cation channel subfamily M member 2 (TRPM2) functioned as an upstream oxidative stress sensor to inhibit autophagy. Moreover, TRPM2-mediated Ca2+ influx activated calpain to shear autophagy related 5 (Atg5) and Atg12-Atg5 conjugate formation was blocked to inhibit autophagy under oxidative stress. More importantly, Atg5 downregulation enhanced the binding of interferon regulatory factor 3 (IRF3) to the CXCL16 promoter region by activating Tank-binding kinase 1 (TBK1), thus promoting CXCL16 secretion. These findings suggested that TRPM2-restrained autophagy promotes CXCL16 secretion via the Atg5-TBK1-IRF3 signaling pathway under oxidative stress. Inhibition of TRPM2 may serve as a potential target for the treatment of vitiligo. © 2024 The Pathological Society of Great Britain and Ireland.

Elimination of intracellular Ca2+ overload by BAPTA‑AM liposome nanoparticles: A promising treatment for acute pancreatitis

Calcium overload, a notable instigator of acute pancreatitis (AP), induces oxidative stress and an inflammatory cascade, subsequently activating both endogenous and exogenous apoptotic pathways. However, there is currently lack of available pharmaceutical interventions to alleviate AP by addressing calcium overload. In the present study, the potential clinical application of liposome nanoparticles (LNs) loaded with 1,2‑bis(2‑aminophenoxy)ethane‑N,N,N',N'‑tetraacetic acid tetrakis (acetoxymethyl ester) (BAPTA‑AM), a cell‑permeant calcium chelator, was investigated as a therapeutic approach for the management of AP. To establish the experimental models in vitro, AR42J cells were exposed to high glucose/sodium oleate (HGO) to induce necrosis, and in vivo, intra‑ductal taurocholate (TC) infusion was used to induce AP. The findings of the present study indicated that the use of BAPTA‑AM‑loaded LN (BLN) effectively and rapidly eliminated excessive Ca2+ and reactive oxygen species, suppressed mononuclear macrophage activation and the release of inflammatory cytokines, and mitigated pancreatic acinar cell apoptosis and necrosis induced by HGO. Furthermore, the systemic administration of BLN demonstrated promising therapeutic potential in the rat model of AP. Notably, BLN significantly enhanced the survival rates of rats subjected to the TC challenge, increasing from 37.5 to 75%. This improvement was attributed to the restoration of pancreatic function, as indicated by improved blood biochemistry indices and alleviation of pancreatic lesions. The potential therapeutic efficacy of BLN in rescuing patients with AP is likely attributed to its capacity to inhibit oxidative stress, prevent premature activation of zymogens and downregulate the expression of TNF‑α, IL‑6 and cathepsin B. Thus, BLN demonstrated promising value as a novel therapeutic approach for promptly alleviating the burden of intracellular Ca2+ overload in patients with AP.

The clinical efficacy and safety of berberine in the treatment of non-alcoholic fatty liver disease: a meta-analysis and systematic review

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is becoming increasingly prevalent worldwide, emerging as a significant health issue on a global scale. Berberine exhibits potential for treating NAFLD, but clinical evidence remains inconclusive. This meta-analysis was conducted to assess the efficacy and safety of berberine for treating NAFLD.

METHODS

This study was registered with PROSPERO (No. CRD42023462338). Identification of randomized controlled trials (RCTs) involved searching 6 databases covering the period from their initiation to 9 September 2023. The primary outcomes comprised liver function markers such as glutamyl transpeptidase (GGT), alanine transaminase (ALT), aspartate transaminase (AST), lipid indices including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), homeostasis model assessment for insulin resistance (HOMA-IR) and body mass index (BMI). Review Manager 5.4 and STATA 17.0 were applied for analysis.

RESULTS

Among 10 RCTs involving 811 patients, berberine demonstrated significant reductions in various parameters: ALT (standardized mean difference (SMD) = - 0.72), 95% confidence interval (Cl) [- 1.01, - 0.44], P < 0.00001), AST (SMD = - 0.79, 95% CI [- 1.17, - 0.40], P < 0.0001), GGT (SMD = - 0.62, 95% CI [- 0.95, - 0.29], P = 0.0002), TG (SMD = - 0.59, 95% CI [- 0.86, - 0.31], P < 0.0001), TC(SMD = - 0.74, 95% CI [- 1.00, - 0.49], P < 0.00001), LDL-C (SMD = - 0.53, 95% CI [- 0.88, - 0.18], P = 0.003), HDL-C (SMD = - 0.51, 95% CI [- 0.12, 1.15], P = 0.11), HOMA-IR (SMD = - 1.56, 95% CI [- 2.54, - 0.58], P = 0.002), and BMI (SMD = - 0.58, 95% CI [- 0.77, - 0.38], P < 0.00001). Importantly, Berberine exhibited a favorable safety profile, with only mild gastrointestinal adverse events reported.

CONCLUSION

This meta-analysis demonstrates berberine's efficacy in improving liver enzymes, lipid profile, and insulin sensitivity in NAFLD patients. These results indicate that berberine shows promise as an adjunct therapy for NAFLD. Trial registration The protocol was registered with PROSPERO (No. CRD42023462338). Registered on September 27, 2023.

Inhibiting Liver Autophagy and Promoting Hepatocyte Apoptosis by Schistosoma Japonicum Infection

We established a mouse model of Schistosoma japonicum infection in order to study the effects of the infection on hepatocyte autophagy and apoptosis. We also stimulated HepG2 cells with soluble egg antigens (SEA) in vitro. At two, four, and six weeks post-infection, quantitative real-time PCR and Western blot (WB) were used to detect liver expression levels of autophagy and apoptosis-related proteins. HepG2 cells were treated with different concentrations of SEA. The changes in the levels of autophagy-related proteins and HepG2 cell apoptosis were detected. The Lc3b, Beclin1, Atg7, and Atg12 mRNA levels were significantly lower at four and six weeks after infection than those in the uninfected group. At four and six weeks following infection, the levels of Beclin1, LC3BII/I, Atg7, and p62 proteins were considerably lower than those in the uninfected group. The protein levels of pro-apoptotic Bax and cleaved caspase 3 and fibrosis-related proteins α-SMA and collagen 3 in the liver post-infection were significantly higher than those in uninfected mice. HepG2 cells stimulated with SEA showed decreased levels of Beclin1, p62, and Atg7 proteins and significantly increased apoptosis rates. The findings demonstrated that following infection with S. japonicum, mice's liver fibrosis worsened, hepatic autophagy was suppressed, and hepatocyte apoptosis was encouraged.

Selenium-Enriched Cardamine violifolia Alleviates LPS-Induced Hepatic Damage and Inflammation by Suppressing TLR4/NODs-Necroptosis Signal Axes in Piglets

Selenium-enriched Cardamine violifolia (SEC), a cruciferous plant, exerts excellent antioxidant and anti-inflammatory capacity, but its effect on hepatic function is unclear. This study investigated the effect and potential mechanism of SEC on hepatic injury induced by lipopolysaccharide (LPS). Twenty-four weaned piglets were randomly allotted to treatment with SEC (0.3 mg/kg Se) and/or LPS (100 μg/kg). After 28 days of the trial, pigs were injected with LPS to induce hepatic injury. These results indicated that SEC supplementation attenuated LPS-induced hepatic morphological injury and reduced aspartate aminotransferase (AST) and alkaline phosphatase (ALP) activities in plasma. SEC also inhibited the expression of pro-inflammatory cytokines such as interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) after the LPS challenge. In addition, SEC improved hepatic antioxidant capacity via enhancing glutathione peroxidase (GSH-Px) activity and decreasing malondialdehyde (MDA) concentration. Moreover, SEC downregulated the mRNA expression of hepatic myeloid differentiation factor 88 (MyD88) and nucleotide-binding oligomerization domain proteins 1 (NOD1) and its adaptor molecule receptor interacting protein kinase 2 (RIPK2). SEC also alleviated LPS-induced hepatic necroptosis by inhibiting RIPK1, RIPK3, and mixed-lineage kinase domain-like (MLKL) expression. These data suggest that SEC potentially mitigates LPS-induced hepatic injury via inhibiting Toll-like receptor 4 (TLR4)/NOD2 and necroptosis signaling pathways in weaned piglets.

Bone Marrow Mesenchymal Stem Cell-Derived Exosomes Ameliorate Aging-Induced BTB Impairment in Porcine Testes by Activating Autophagy and Inhibiting ROS/NLRP3 Inflammasomes via the AMPK/mTOR Signaling Pathway

As a pivotal player in spermatogenesis, the blood-testis barrier (BTB) made from junction apparatus coexisting in Sertoli cells (SCs) is impaired with an increase in age and ultimately induces spermatogenic dysfunction or even infertility. It has been corroborated that bone marrow mesenchymal stem cell (BMSC) transplantation can efficiently repair and regenerate the testicular function. As vital mediators of cell-to-cell communication, MSC-derived exosomes (Exos) can directly serve as therapeutic agents for tissue repair and regeneration. However, the therapeutic value of BMSC-Exos in aging-induced BTB damage remains to be confirmed. In this study, we explored that the old porcine testes had defective autophagy, which aggravated BTB disruption in SCs. BMSC-Exos could decrease ROS production and NLRP3 inflammasome activation but enhanced autophagy and tight junction (TJ) function in D-gal-triggered aging porcine SCs and mouse model testes, according to in vitro and in vivo experiments. Furthermore, rapamycin, NAC, MCC950, and IL-1Ra restored the TJ function in D-gal-stimulated aging porcine SCs, while BMSC-Exos' stimulatory effect on TJ function was inhibited by chloroquine. Moreover, the treatment with BMSC-Exos enhanced autophagy in D-gal-induced aging porcine SCs by means of the AMPK/mTOR signal transduction pathway. These findings uncovered through the present study that BMSC-Exos can enhance the BTB function in aging testes by improving autophagy via the AMPK/mTOR signaling pathway, thereby suppressing ROS production and NLRP3 inflammasome activation.

Research Progress on the Effect of Autophagy and Exosomes on Liver Fibrosis

Chronic liver disease is a known risk factor for the development of liver cancer, and the development of microRNA (miRNA) liver therapies has been hampered by the difficulty of delivering miRNA to damaged tissues. In recent years, numerous studies have shown that hepatic stellate cell (HSC) autophagy and exosomes play an important role in maintaining liver homeostasis and ameliorating liver fibrosis. In addition, the interaction between HSC autophagy and exosomes also affects the progression of liver fibrosis. In this paper, we review the research progress of mesenchymal stem cell-derived exosomes (MSC-EVs) loaded with specific miRNA and autophagy, and their related signaling pathways in liver fibrosis, which will provide a more reliable basis for the use of MSC-EVs for therapeutic delivery of miRNAs targeting the chronic liver disease.

GRP78 improves the therapeutic effect of mesenchymal stem cells on hemorrhagic shock-induced liver injury: Involvement of the NF-кB and HO-1/Nrf-2 pathways

Mesenchymal stem cells (MSCs) are a popular cell source for repairing the liver. Improving the survival rate and colonization time of MSCs may significantly improve the therapeutic outcomes of MSCs. Studies showed that 78-kDa glucose-regulated protein (GRP78) expression improves cell viability and migration. This study aims to examine whether GRP78 overexpression improves the efficacy of rat bone marrow-derived MSCs (rBMSCs) in HS-induced liver damage. Bone marrow was isolated from the femurs and tibias of rats. rBMSCs were transfected with a GFP-labeled GRP78 expression vector. Flow cytometry, transwell invasion assay, scratch assay immunoblotting, TUNEL assay, MTT assay, and ELISA were carried out. The results showed that GRP78 overexpression enhanced the migration and invasion of rBMSCs. Moreover, GRP78-overexpressing rBMSCs relieved liver damage, repressed liver oxidative stress, and inhibited apoptosis. We found that overexpression of GRP78 in rBMSCs inhibited activation of the NLRP3 inflammasome, significantly decreased the levels of inflammatory factors, and decreased the expression of CD68. Notably, GRP78 overexpression activated the Nrf-2/HO-1 pathway and inhibited the NF-κB pathway. High expression of GRP78 efficiently enhanced the effect of rBMSC therapy. GRP78 may be a potential target to improve the therapeutic efficacy of BMSCs.

Dynamic expression analysis of peripheral blood derived small extracellular vesicle miRNAs in sepsis progression

Immune disorders caused by sepsis have recently drawn much attention. We sought to dynamically monitor the expression of small extracellular vesicle (sEV) miRNAs in peripheral blood during sepsis to explore these miRNAs as potential biomarkers for monitoring immune function in sepsis patients. This study included patients with sepsis. Blood samples were obtained from 10 patients on the first through 10th days, the 12th day and the 14th day since sepsis onset, resulting in 120 collected samples. Serum sEVs were extracted from peripheral venous blood, and levels of MIR497HG, miR-195, miR-497, and PD-L1 in serum sEVs were detected by qPCR, and clinical information was recorded. Our study revealed that the levels of MIR497HG, miR-195, miR-497 and PD-L1 in serum sEVs showed periodic changes; the time from peak to trough was approximately 4-5 days. The levels of sEV MIR497HG and miR-195 had a positive linear relationship with SOFA score (r values were -0.181 and -0.189; p values were 0.048 and 0.039, respectively). The recorded quantities of sEV MIR497HG, miR-195 and PD-L1 showed a substantial correlation with ARDS. ROC curve analysis revealed that sEV MIR497HG, miR-195 and miR-497 could predict the 28-day mortality of sepsis patients with an AUC of 0.66, 0.68 and 0.72, respectively. Levels of sEVs MIR497HG, miR-195, miR-497 and PD-L1 showed periodic changes with the immune status of sepsis, which provides a new exploration direction for immune function biomarkers and immunotherapy timing in sepsis patients.

An update: is there a relationship between H. pylori infection and nonalcoholic fatty liver disease? why is this subject of interest?

Helicobacter pylori (H. pylori) infection is thought to impact various extragastric diseases, including nonalcoholic fatty liver disease (NAFLD), the most common chronic liver disease. Meanwhile, the pathogenesis of NAFLD needs further research, and effective treatment for this disease remains elusive. In this mini-review, we enumerate and ponder on the evidence demonstrating an association between H. pylori infection and NAFLD. Primarily, we delve into high-quality meta-analyses and clinical randomized controlled trials focusing on the association studies between the two. We also discuss clinical studies that present opposite conclusions. In addition, we propose a mechanism through which H. pylori infection aggravates NAFLD: inflammatory cytokines and adipocytokines, insulin resistance, lipid metabolism, intestinal barrier and microbiota, H. pylori outer membrane vesicles and H. pylori-infected cell-extracellular vesicles. This mini-review aims to further explore NAFLD pathogenesis and extragastric disease mechanisms caused by H. pylori infection.

Macrophage autophagy contributes to immune liver injury in trichloroethylene sensitized mice: Critical role of TNF-α mediating mTOR pathway

Trichloroethylene (TCE) induces occupational medicamentosa-like dermatitis due to TCE (OMDT) with immune liver injury, and TNF-α plays an important role in macrophage polarization and liver injury. However, TNF-α regulating macrophage polarization in liver injury induced by TCE is still unknown. Thus, on the basis of our previous research, we established the TCE-sensitized BALB/c mouse model with R7050, a specific inhibitor of TNFR1. Then, we observed significant decreases in autophagy related protein and gene levels in M1 macrophage in TCE positive group, and R7050 can relieve M1 macrophage autophagy. We also found the phosphorylated form of mammalian target of Rapamycin (mTOR) was activated and the expression of p-mTOR protein increased induce by TCE. In vitro, we found TNFR1 and CD11c were increased in RAW264.7 cell line with TNF-α. And then we use Zafirlukast (Zaf), an TNFR1 antagonist, CD11c and TNFR1 reduced significantly, we also found p-mTOR expression increased after TNF-α treatment, but decreased in TNF-α + Zaf group. Further, we used Rapamycin (RAP), a mTOR-specific inhibitor, to establish a TCE-sensitized mice model and found the expression levels of p62 and p-mTOR proteins increased and LC3B decreased in the TCE positive group, while RAP treatment reversed the trends of all of these proteins. Rapamycin prevented the TNF-α-induced p-mTOR increase and dramatically downregulated IL-1β expression in the RAW264.7 cell line with TNF-α treatment. The results uncover a novel role for TNF-α/TNFR1, which promotes M1 polarization of macrophage and suppresses macrophage autophagy via the mTOR pathway.

Swertia bimaculata moderated liver damage in mice by regulating intestine microbiota

Swertia bimaculata (SB) is a medicinal herb in China having an array of therapeutic and biological properties. This study aimed to explore the attenuating effect of SB on carbon tetrachloride (CCl4) induced hepato-toxicity by regulation of gut microbiome in ICR mice. For this purpose, CCl4 was injected intraperitoneally in different mice groups (B, C, D and E) every 4th day for a period of 47 days. Additionally, C, D, and E groups received a daily dose (50 mg/kg, 100 mg/kg, and 200 mg/kg respectively) of Ether extract of SB via gavage for the whole study period. The results of serum biochemistry analysis, ELISA, H&E staining, and sequencing of the gut microbiome, indicated that SB significantly alleviates the CCl4-induced liver damage and hepatocyte degeneration. The serum levels of alanine transaminase, aspartate aminotransferase, malondialdehyde, interleukin 1 beta and tumor necrosis factor-alpha were significantly lower in SB treated groups compared to control while levels of glutathione peroxidase were raised. Also, the sequencing data indicate that supplementation with SB could restore the microbiome and its function in CCl4-induced variations in intestinal microbiome of mice by significantly downregulating the abundances of pathogenic intestinal bacteria species including Bacteroides, Enterococcus, Eubacterium, Bifidobacterium while upregulating the levels of beneficial bacteria like Christensenella in the gut. In conclusion, we revealed that SB depicts a beneficial effect against hepatotoxicity induced by CCl4 in mice through the remission of hepatic inflammation and injury, through regulation of oxidative stress, and by restoring gut microbiota dysbiosis.

Insulin reverses impaired alveolar fluid clearance in ARDS by inhibiting LPS-induced autophagy and inflammatory

Until now, acute respiratory distress syndrome (ARDS) has been a difficult clinical condition with a high mortality and morbidity rate, and is characterized by a build-up of alveolar fluid and impaired clearance. The underlying mechanism is not yet fully understood and no effective medications available. Autophagy activation is associated with ARDS caused by different pathogenic factors. It represents a new direction of prevention and treatment of ARDS to restrain autophagy to a reasonable level through pharmacological and molecular genetic methods. Na, K-ATPase is the main gradient driver of pulmonary water clearance in ARDS and could be degraded by the autophagy-lysosome pathway to affect its abundance and enzyme activity. As a normal growth hormone in human body, insulin has been widely used in clinical for a long time. To investigate the association of insulin with Na, K-ATPase, autophagy and inflammatory markers in LPS-treated C57BL/6 mice by survival assessment, proteomic analysis, histologic examination, inflammatory cell counting, myeloperoxidase, TNF-α and IL-1β activity analysis etc. This was also verified on mouse alveolar epithelial type II (AT II) and A549 cells by transmission electron microscopy. We found that insulin restored the expression of Na, K-ATPase, inhibited the activation of autophagy and reduced the release of inflammatory factors caused by alveolar epithelial damage. The regulation mechanism of insulin on Na, K-ATPase by inhibiting autophagy function may provide new drug targets for the treatment of ARDS.

Cross-talk between the RAS-ERK and mTOR signalings-associated autophagy contributes to tripterygium glycosides tablet-induced liver injury

BACKGROUND AND AIMS

Drug-induced liver injury (DILI) remains a critical issue and a hindrance to clinical application of Tripterygium Glycosides Tablet (TGT) despite its favorable therapeutic efficacy in rheumatoid arthritis. Herein, we aimed to elucidate the molecular mechanisms underlying TGT-induced hepatotoxicity.

METHODS

Chemical profiling of TGT was identified by UPLC-Q/TOF-MS/MS and its putative targets were predicted based on chemical structure similarity calculation. Following "DILI-related gene-TGT putative target" interaction network construction, a list of key network targets was screened according to nodes' topological importance and functional relevance. Both in vivo and in vitro experiments were performed to determine drug hepatotoxicity and the underlying mechanisms.

RESULT

A total of 49 chemical components and 914 putative targets of TGTs were identified. Network calculation and functional modularization screened RAS-ERK and mTOR signalings-associated autophagy to be one of the candidate targets of TGT-induced hepatotoxicity. Experimentally, TGT significantly activated RAS-ERK axis, elevated the number of autophagosomes and the expression of LC3II protein, but reduced the expression of p62 protein and suppressed mTOR phosphorylation in the liver tissues of TGT-induced acute liver injury mice and chronic liver injury mice in vivo and AML12 cells in vitro. Moreover, TGT and mL-098 (an activator of RAS) co-treatment reduced AML12 cell viability via regulating autophagy and TGT-induced liver injury-related indicators more dramatically than TGT treatment alone, whereas Salirasib (an inhibitor of RAS) had an opposite effect.

CONCLUSION

RAS-ERK-mTOR cross-talk may play a crucial role in TGT-induced hepatocyte autophagy, offering a promising target for developing novel therapeutics to combat TGT-induced hepatotoxicity.

Endoplasmic reticulum stress regulates autophagic response that is involved in Saikosaponin a-induced liver cell damage

Saikosaponin a (Ssa) is an active ingredient of the Chinese herbal plant Radix Bupleuri (RB) and has severe hepatotoxicity. However, biomolecular mechanisms involved in Ssa-induced hepatotoxicity are not yet entirely clear. Previous studies reported that Ssd (an isomer of Ssa) as a sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA) inhibitor can induce autophagy in apoptotic defective cells, leading to autophagy-dependent cell death. Therefore, we speculate that endoplasmic reticulum (ER) stress and autophagy may also play an important role in Ssa-induced hepatocyte death. This study aimed to explore the connection between ER stress and autophagy and Ssa-induced hepatotoxicity. Experiments in vitro showed that the cell viability of L-02 cells in the Ssa treatment group decreased, the level of autophagy marker LC3-II/LC3-I and Beclin1 increased, the level of p62 decreased, the colocalization of autophagosome and lysosome increased, and the cell viability was significantly increased after the application of autophagy inhibitors 3-MA. In addition, SSa can induce ER stress in L-02 cells in vitro. Further studies demonstrated that SSa activated the PERK/eIF2α/ATF4/CHOP pathway, IRE1-TRAF2 pathway, ATF6 pathway, and AMPK/mTOR pathway associated with ER stress. Application of ER stress inhibitors 4-PBA can significantly down-regulate the level of autophagy and improve cell viability. Results of in vivo experiments showed that treatment with 150 and 300 mg/kg Ssa significantly elevated the liver/body weight ratio and caused histological injury in mice liver. Furthermore, Ssa treatment induced significantly downregulated p62 expression but upregulated LC3-II, CHOP, and GRP78 expression in mice livers. Taken together, our results showed that SSa can activate endoplasmic reticulum stress, promote toxic autophagy, and then induce cell death. We revealed an alternative mechanism involving autophagy and ERs, by which Ssa induced hepatotoxicity.

Autophagy and exosomes coordinately mediate quercetin's protective effects on alcoholic liver disease

Alcoholic liver disease (ALD), a spectrum of liver abnormalities induced by chronic alcohol abuse, continues to be the major cause of life-threatening liver disease in developed countries. Autophagy and exosomes were individually confirmed to be involved in the pathogenesis of ALD. Here, we sought to identify the role of autophagy and exosomes in the liver protective effects of quercetin. We observed decreased hepatic LC3II/LC3I and increased p62 level in ethanol-fed mice, and these changes were alleviated by quercetin. Meanwhile, nanoparticle tracking analysis (NTA) showed elevated serum exosomes numbers in ethanol-fed mice, which was combated by quercetin. Ethanol induced elevated LDH, ALT, and AST in HepG2 supernatant, which was alleviated by cytochalasin D (exosomes uptake inhibitor). Moreover, quercetin reduced ethanol-induced LDH and ALT elevation in vitro, and the effects of quercetin were reversed by Rab27a overexpression (induce exosomes release) or wortmannin treatment (autophagy inhibitor). Transcriptomic analysis supported that quercetin reversed the change of lysosome related genes disturbed by ethanol. Meanwhile, western blot analysis exhibited decreased hepatic expression of LAMP2 and ATPA6V1B2, and active Cathepsin B/Cathepsin B by quercetin treatment, indicating quercetin alleviated lysosome dysfunction in ethanol-fed mice. Baf A treatment or transfection of siTFEB offset quercetin's effects in ethanol-induced LDH and ALT elevation, exosomes release, and autophagy inhibition (LC3II/I and p62 accumulation). Taken together, quercetin coordinately activates autophagy and combats exosomes release by restoring lysosome function, and further mitigates ethanol-induced liver damage.

Hydrogen sulfide alleviates ischemia induced liver injury by repressing the SPHK1/S1P pathway

Background

Ischemia/reperfusion (I/R) induced liver injury is a severe pathological process which frequently occurs during clinical hepatic operations. The current study investigated the protective function and underlying mechanisms of hydrogen sulfide (H₂S) in I/R induced liver injury.

Methods

The effects of H₂S were examined using the fibroblast-like rat liver cell line BRL-3A (the name of normal hepatocytes in rats) cultured under hypoxic conditions and an I/R rat model. The viability of BRL-3A cells was assessed using the methylthiazolyldiphenyl-tetrazolium (MTT) assay and Hoechst analysis. The expression of C/EBP homologous protein (CHOP), sphingosine kinase 1 (SPHK1), and sphingosine 1-phosphate (S1P) were determined in hypoxic BRL-3A cells with or without H₂S treatment. CHOP was overexpressed in hypoxic BRL-3A cells to further evaluate whether H₂S protected the liver against I/R injury by decreasing endoplasmic reticulum (ER) stress. Finally, the inflammation levels in the serum and the histopathological changes of liver were examined in the I/R rat model to evaluate the therapeutic function of H₂S on I/R induced liver injury in vivo.

Results

H₂S alleviated hypoxic damage in BRL-3A cells. In addition, hypoxia increased the expression of CHOP, SPHK1, and S1P in BRL-3A cells, and this was abolished by H₂S pretreatment. Notably, overexpression of CHOP significantly inhibited the effect of H₂S on the viability of BRL-3A cells during hypoxia. Overall, H₂S effectively protected against I/R induced liver injury, decreased the inflammatory responses, and attenuated apoptosis of hepatocyte via inhibiting the ER stress response.

Conclusions

These findings demonstrated that pre-treatment of H₂S protected against I/R induced liver injury by repressing the SPHK1/S1P pathway via inhibition of ER stress, suggesting an effective therapeutic method for the treatment of I/R induced liver injury.

Recent Advances in Understanding of Pathogenesis of Alcohol-Associated Liver Disease

Alcohol-associated liver disease (ALD) is one of the major diseases arising from chronic alcohol consumption and is one of the most common causes of liver-related morbidity and mortality. ALD includes asymptomatic liver steatosis, fibrosis, cirrhosis, and alcohol-associated hepatitis and its complications. The progression of ALD involves complex cell-cell and organ-organ interactions. We focus on the impact of alcohol on dysregulation of homeostatic mechanisms and regulation of injury and repair in the liver. In particular, we discuss recent advances in understanding the disruption of balance between programmed cell death and prosurvival pathways, such as autophagy and membrane trafficking, in the pathogenesis of ALD. We also summarize current understanding of innate immune responses, liver sinusoidal endothelial cell dysfunction and hepatic stellate cell activation, and gut-liver and adipose-liver cross talk in response to ethanol. In addition,we describe the current potential therapeutic targets and clinical trials aimed at alleviating hepatocyte injury, reducing inflammatory responses, and targeting gut microbiota, for the treatment of ALD.

Hepatocytes: A key role in liver inflammation

Hepatocytes, the major parenchymal cells in the liver, are responsible for a variety of cellular functions including carbohydrate, lipid and protein metabolism, detoxification and immune cell activation to maintain liver homeotasis. Recent studies show hepatocytes play a pivotal role in liver inflammation. After receiving liver insults and inflammatory signals, hepatocytes may undergo organelle damage, and further respond by releasing mediators and expressing molecules that can act in the microenvironment as well as initiate a robust inflammatory response. In this review, we summarize how the hepatic organelle damage link to liver inflammation and introduce numerous hepatocyte-derived pro-inflammatory factors in response to chronic liver injury.

Novel tryptanthrin derivatives with benzenesulfonamide substituents: Design, synthesis, and anti-inflammatory evaluation

Herein, two series of tryptanthrin derivatives with benzenesulfonamide substituents were designed and synthesized to discover novel anti-inflammatory agents. The anti-inflammatory activities of all derivatives were screened by evaluating their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells. Among them, compound 8j exhibited the best NO inhibitory activity (IC₅₀ = 1.25 ± 0.21 μM), with no obvious toxicity. Further evaluation showed that 8j could also significantly reduce the levels of pro-inflammatory cytokines interleukin-1β (IL-1β, IC₅₀ = 8.48 ± 0.23 μM) and tumor necrosis factor-α (TNF-α, IC₅₀ = 11.53 ± 0.35 μM) and downregulate the LPS-induced expression of iNOS and COX-2. Reverse docking of 8j suggested p38α as the molecular target, which is a well-known crucial player in the p38 MAPK signaling pathway that controls the transcription of pro-inflammatory mediators. Cellular thermal shift assay showed that 8j efficiently stabilized p38α in LPS-treated RAW264.7 cells. Western blot showed that inflammatory response was inhibited by 8j through inhibiting the phosphorylation of p38α and MK2 in the p38 MAPK signaling pathway. Finally, In vivo studies showed that 8j could significantly ameliorate the degree of foot swelling and knee joint pathology in adjuvant-induced arthritis (AIA) rats and reduce levels of TNF-α and IL-1β in serum, achieving the effect of protecting synovial tissue and ameliorating arthritis. These findings suggested that 8j may be a promising compound for further development of anti-inflammatory agents.

Role of Small Extracellular Vesicles in Liver Diseases: Pathogenesis, Diagnosis, and Treatment

Extracellular vesicles (EVs) are vesicular bodies that bud off from the cell membrane or are secreted virtually by all cell types. Small EVs (sEVs or exosomes) are key mediators of cell-cell communication by delivering their cargo, including proteins, lipids, or RNAs, to the recipient cells where they induce changes in signaling pathways and phenotypic properties. Tangible findings have revealed the pivotal involvement of sEVs in the pathogenesis of various diseases. On the bright side, they are rich sources of biomarkers for diagnosis, prognosis, treatment response, and disease monitoring. sEVs have high stability, biocompatibility, targetability, low toxicity, and are immunogenic in nature. Their intrinsic properties make sEVs an ideal delivery vehicle to be loaded with cargo for therapeutic interventions. Liver diseases are a major global health problem. This review aims to focus on the roles and mechanisms of sEVs in the pathogenesis of liver diseases, liver injury, liver failure, and liver cancer. sEVs are released not only by hepatocytes but also by stromal and immune cells in the microenvironment. Early detection of liver disease determines the chance for curative treatment and high survival of patients. This review focuses on the potential of circulating sEV cargo as specific and sensitive noninvasive biomarkers for the early detection and prognosis of liver diseases. In addition, the therapeutic use of sEVs derived from various cell types is discussed. Although sEVs hold promise for clinical applications, there are still challenges to be overcome by further research to bring utilization of sEVs into clinical practice.

Molecular mechanisms of ferroptosis and relevance to inflammation

INTRODUCTION

Inflammation is a defensive response of the organism to irritation which is manifested by redness, swelling, heat, pain and dysfunction. The inflammatory response underlies the role of various diseases. Ferroptosis, a unique modality of cell death, driven by iron-dependent lipid peroxidation, is regulated by multifarious cellular metabolic pathways, including redox homeostasis, iron processing and metabolism of lipids, as well as various signaling pathways associated with diseases. A growing body of evidence suggests that ferroptosis is involved in inflammatory response, and targeting ferroptosis has great prospects in preventing and treating inflammatory diseases.

MATERIALS AND METHODS

Relevant literatures on ferroptosis, inflammation, inflammatory factors and inflammatory diseases published from January 1, 2010 to now were searched in PubMed database.

CONCLUSION

In this review, we summarize the regulatory mechanisms associated with ferroptosis, discuss the interaction between ferroptosis and inflammation, the role of mitochondria in inflammatory ferroptosis, and the role of targeting ferroptosis in inflammatory diseases. As more and more studies have confirmed the relationship between ferroptosis and inflammation in a wide range of organ damage and degeneration, drug induction and inhibition of ferroptosis has great potential in the treatment of immune and inflammatory diseases.

Shuangyu Tiaozhi decoction alleviates non-alcoholic fatty liver disease by improving lipid deposition, insulin resistance, and inflammation in vitro and in vivo

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. Our previous studies have found that Shuangyu Tiaozhi Decoction (SYTZD) could produce an improvement in NAFLD-related indicators, but the underlying mechanism associated with this improvement remains unclear. The study aimed to investigate the potential mechanism of SYTZD against NAFLD through network pharmacology and experimental verification. The components of SYTZD and SYTZD drug containing serum were analyzed using ultra-performance liquid chromatography to quadrupole/time-of-flight mass spectrometry (UPLC-Q/TOF-MS). Active components and targets of SYTZD were screened by the traditional Chinese medical systems pharmacology (TCMSP) and encyclopedia of traditional Chinese medicine (ETCM) databases. NAFLD-related targets were collected from the GeneCards and DisGeNET databases. The component-disease targets were mapped to identify the common targets of SYTZD against NAFLD. Protein-protein interaction (PPI) network of the common targets was constructed for selecting the core targets. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of the core targets was performed using the database for annotation, visualization, and integrated discovery (DAVID) database. Furthermore, animal and cell models were constructed for validating the predictions of network pharmacology. Lipid accumulation, liver histopathology, insulin resistance, and core gene expression were measured by oil red O staining, hematoxylin and eosin staining, insulin tolerance test, real-time quantitative polymerase chain reaction, and Western blotting, respectively. Two components and 22 targets of SYTZD against NAFLD were identified by UPLC-Q/TOF-MS and relevant databases. PPI analysis found that ESR1, FASN, mTOR, HIF-1α, VEGFA, and GSK-3β might be the core targets of SYTZD against NAFLD, which were mainly enriched in the thyroid hormone pathway, insulin resistance pathway, HIF-1 pathway, mTOR pathway, and AMPK pathway. Experimental results revealed that SYTZD might exert multiple anti-NAFLD mechanisms, including improvements in lipid deposition, inflammation, and insulin resistance. SYTZD treatment led to decreases in the lipid profiles, hepatic enzyme levels, inflammatory cytokines, and homeostatic model assessment for insulin resistance (HOMA-IR). SYTZD treatment affected relative mRNA and protein levels associated with various pathways. Our findings reveal that SYTZD could alleviate NAFLD through a multi-component, multi-target, and multi-pathway mechanism of action.

ACBP/DBI protein neutralization confers autophagy-dependent organ protection through inhibition of cell loss, inflammation, and fibrosis

Acyl-coenzyme A (CoA)-binding protein (ACBP), also known as diazepam-binding inhibitor (DBI), is an extracellular feedback regulator of autophagy. Here, we report that injection of a monoclonal antibody neutralizing ACBP/DBI (α-DBI) protects the murine liver against ischemia/reperfusion damage, intoxication by acetaminophen and concanavalin A, and nonalcoholic steatohepatitis caused by methionine/choline-deficient diet as well as against liver fibrosis induced by bile duct ligation or carbon tetrachloride. α-DBI downregulated proinflammatory and profibrotic genes and upregulated antioxidant defenses and fatty acid oxidation in the liver. The hepatoprotective effects of α-DBI were mimicked by the induction of ACBP/DBI-specific autoantibodies, an inducible Acbp/Dbi knockout or a constitutive Gabrg2^F77I mutation that abolishes ACBP/DBI binding to the GABA_A receptor. Liver-protective α-DBI effects were lost when autophagy was pharmacologically blocked or genetically inhibited by knockout of Atg4b. Of note, α-DBI also reduced myocardium infarction and lung fibrosis, supporting the contention that it mediates broad organ-protective effects against multiple insults.

Lagotis brachystachya maxim attenuates chronic alcoholic liver injury combined with gouty arthritis in rats via its anti-inflammatory activity

Lagotis brachystachya Maxim, a common herb in Tibetan medicine, is mainly used to treat pneumonia, hepatitis, yellow water disease (gouty arthritis). Since long-term heavy drinking is also a risk factor for gouty arthritis, the present study aimed to evaluate the underlying protective role and mechanism of extracts of Lagotis brachystachya (ELB) in chronic alcoholic liver injury combined with gouty arthritis. The rat chronic alcoholic liver injury combined with gouty arthritis model was established by long-term alcohol consumption and monosodium urate (MSU) injection. The therapeutical action of ELB was then evaluated by biochemical measurement, histopathological examination, ankle swelling assessment, and protein detection. According to biochemical measurements and histopathological evaluation, ELB could alleviate the symptoms of alcoholic liver injury combined with gouty arthritis. In addition, chronic alcohol consumption and MSU activated inflammatory-related signaling such as TLR4/MyD88/NF-κB, NLRP3, and JAK2/STAT3 pathways in the liver and synovial tissues, while ELB significantly inhibited the activation of the inflammatory signaling pathway. In conclusion, ELB is protective in rats with chronic alcoholic liver injury and gouty arthritis, possibly mediated by the inhibition of TLR4/MyD88/NF-κB, NLRP3, and JAK2-STAT3 signaling pathways in both the hepatic and synovial tissues.

Chrysophanol-8-O-glucoside protects mice against acute liver injury by inhibiting autophagy in hepatic stellate cells and inflammatory response in liver-resident macrophages

Acute liver failure (ALF) is an unfavorable condition characterized by the rapid loss of liver function and high mortality. Chrysophanol-8-O-glucoside (CPOG) is an anthraquinone derivative isolated from rhubarb. This study aims to evaluate the protective effect of CPOG on lipopolysaccharide (LPS)/D-GalN-induced ALF and its underlying mechanisms. LPS/D-GalN-induced mice ALF model and LPS treatment model in RAW 264.7 and LX2 cells were established. It was found that CPOG ameliorated LPS/D-GalN-induced liver injury and improved mortality as indicated by Hematoxylin-eosin (H&amp;E) staining. Molecularly, qPCR and ELISA results showed that CPOG alleviated LPS/D-GalN-induced release of alanine aminotransferase and aspartate transaminase and the secretion of TNF-α and IL-1β in vivo. LPS/D-GalN-induced intracellular ROS production was also attenuated by CPOG in liver tissue. Further, CPOG attenuated ROS generation and inhibited the expression of p-IκB and p-p65 as well as the expression of TNF-α and IL-1β stimulated by LPS in RAW 264.7 cells. In addition, CPOG alleviated LPS-induced up-regulation of LC3B, p62, ATG5 and Beclin1 by attenuating ROS production and inhibiting MAPK signaling in LX2 cells. Taken together, our data indicated that the CPOG protected against LPS/D-GalN-induced ALF by inhibiting oxidative stress, inflammation response and autophagy. These findings suggest that CPOG could be potential drug for the treatment of ALF in clinic.

Hepatic interleukin-1 receptor type 1 signalling regulates insulin sensitivity in the early phases of nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is associated with hepatic as well as systemic insulin resistance even in the absence of type 2 diabetes. The extent and pathways through which hepatic inflammation modulates insulin sensitivity in NAFLD are only partially understood. We explored the contribution of hepatic interleukin (IL)-1 signalling in a novel conditional knockout mouse model and expand the knowledge on this signalling pathway with regard to its liver-specific functions.

METHODS

A high-fat, high-carbohydrate diet (HFD) over 12 weeks was used in male hepatocyte-specific IL-1 receptor type 1 (IL-1R1) knockout mice (Il1r1Hep-/- ) and wild-type (WT) littermates.

RESULTS

Both genotypes developed an obese phenotype and accompanying macrovesicular hepatic steatosis. In contrast to WT mice, microvesicular steatosis and ballooning injury was less pronounced in HFD-fed Il1r1Hep-/- mice, and alanine aminotransferase remained in the normal range. This was paralleled by the suppression of injurious and proinflammatory hepatic c-Jun N-terminal kinases and extracellular signal-regulated kinases signalling, stable peroxisome proliferator activated receptor gamma coactivator-1alpha and farnesoid X receptor-alpha expression and preservation of mitochondrial function. Strikingly, despite HFD-feeding Il1r1Hep-/- mice remained highly insulin sensitive as indicated by lower insulin levels, homeostatic model assessment for insulin resistance, higher glucose tolerance, more stable hepatic insulin signalling cascade, and less adipose tissue inflammation compared to the WT.

CONCLUSIONS

The current data highlights that hepatocyte IL-1R1 contributes to hepatic and extrahepatic insulin resistance. Future liver-directed therapies in NAFLD could have effects on insulin sensitivity when improving hepatic inflammation and IL-1R1 signalling.

Rare ATG7 genetic variants predispose patients to severe fatty liver disease

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is the leading cause of liver disorders and has a strong heritable component. The aim of this study was to identify new loci that contribute to severe NAFLD by examining rare variants.

METHODS

We performed whole-exome sequencing in individuals with NAFLD and advanced fibrosis or hepatocellular carcinoma (n = 301) and examined the enrichment of likely pathogenic rare variants vs. the general population. This was followed by validation at the gene level.

RESULTS

In patients with severe NAFLD, we observed an enrichment of the p.P426L variant (rs143545741 C>T; odds ratio [OR] 5.26, 95% CI 2.1-12.6; p = 0.003) of autophagy-related 7 (ATG7), which we characterized as a loss-of-function, vs. the general population, and an enrichment in rare variants affecting the catalytic domain (OR 13.9; 95% CI 1.9-612; p = 0.002). In the UK Biobank cohort, loss-of-function ATG7 variants increased the risk of cirrhosis and hepatocellular carcinoma (OR 3.30; 95% CI 1.1-7.5 and OR 12.30, 95% CI 2.6-36, respectively; p <0.001 for both). The low-frequency loss-of-function p.V471A variant (rs36117895 T>C) was also associated with severe NAFLD in the clinical cohort (OR 1.7; 95% CI 1.2-2.5; p = 0.003), predisposed to hepatocellular ballooning (p = 0.007) evolving to fibrosis in the Liver biopsy cohort (n = 2,268), and was associated with liver injury in the UK Biobank (aspartate aminotransferase levels, p <0.001), with a larger effect in severely obese individuals in whom it was linked to hepatocellular carcinoma (p = 0.009). ATG7 protein localized to periportal hepatocytes, particularly in the presence of ballooning. In the Liver Transcriptomic cohort (n = 125), ATG7 expression correlated with suppression of the TNFα pathway, which was conversely upregulated in p.V471A carriers.

CONCLUSIONS

We identified rare and low-frequency ATG7 loss-of-function variants that promote NAFLD progression by impairing autophagy and facilitating ballooning and inflammation.

LAY SUMMARY

We found that rare mutations in a gene called autophagy-related 7 (ATG7) increase the risk of developing severe liver disease in individuals with dysmetabolism. These mutations cause an alteration in protein function and impairment of self-renewal of cellular content, leading to liver damage and inflammation.

Integrated regulation of stress responses, autophagy and survival by altered intracellular iron stores

Iron is a mineral essential for blood production and a variety of critical cellular functions. Altered iron metabolism has been increasingly observed in many diseases and disorders, but a comprehensive and mechanistic understanding of the cellular impact of impaired iron metabolism is still lacking. We examined the effects of iron overload or iron deficiency on cellular stress responses and autophagy which collectively regulate cell homeostasis and survival. Acute iron loading led to increased mitochondrial ROS (mtROS) production and damage, lipid peroxidation, impaired autophagic flux, and ferroptosis. Iron-induced mtROS overproduction is the mechanism of increased lipid peroxidation, impaired autophagy, and the induction of ferroptosis. Iron excess-induced ferroptosis was cell-type dependent and regulated by activating transcription factor 4 (ATF4). Upregulation of ATF4 mitigated iron-induced autophagic dysfunction and ferroptosis, whereas silencing of ATF4 expression impaired autophagy and resulted in increased mtROS production and ferroptosis. Employing autophagy-deficient hepatocytes and different autophagy inhibitors, we further showed that autophagic impairment sensitized cells to iron-induced ferroptosis. In contrast, iron deficiency activated the endoplasmic reticulum (ER) stress response, decreased autophagy, and induced apoptosis. Decreased autophagy associated with iron deficiency was due to ER stress, as reduction of ER stress by 4-phenylbutyric acid (4-PBA) improved autophagic flux. The mechanism of decreased autophagy in iron deficiency is a disruption in lysosomal biogenesis due to impaired posttranslational maturation of lysosomal membrane proteins. In conclusion, iron excess and iron deficiency cause different forms of cell stress and death in part through the common mechanism of impaired autophagic function.

Effects of dietary lysolecithin on growth performance, serum biochemical indexes, antioxidant capacity, lipid metabolism and inflammation-related genes expression of juvenile large yellow croaker (Larimichthys crocea)

A 70-day feeding trial was conducted to investigate effects of dietary lysolecithin on growth performance, serum biochemical indexes, antioxidant capacity, lipid metabolism and inflammation-related genes expression of juvenile large yellow croaker (Larimichthys crocea) with initial weight of 6.04 ± 0.08 g. A formulated diet containing approximately 42% crude protein and 12.5% crude lipid was used as the control diet (CON). The other three experimental diets were formulated with supplementation of 0.2%, 0.4% and 0.6% lysolecithin based on the control diet, respectively. Results showed that weight gain rate (WGR) and specific growth rate (SGR) significantly increased in fish fed diets with lysolecithin compared with those in the control diet (P < 0.05). Fish fed diets with 0.4% and 0.6% lysolecithin had notably higher lipid content in muscle than that in the control diet (P < 0.05). When fish were fed diets with lysolecithin, serum high-density lipoprotein cholesterol (HDL-c) content was notably higher than that in the control diet (P < 0.05), while fish fed the diet with 0.6% lysolecithin had a significant lower serum low-density lipoprotein cholesterol (LDL-c) content than that in the control diet (P < 0.05). Meanwhile, serum aspartate transaminase (AST) and alanine transaminase (ALT) activities in fish fed diets with lysolecithin were remarkably lower than those in the control diet (P < 0.05). With the increase of dietary lysolecithin from 0.2% to 0.6%, mRNA expression of stearoyl-coenzyme A desaturase 1 (scd1), diacylglycerol acyltransferase 2 (dgat2) and sterol-regulatory element binding protein 1 (srebp1) showed decreasing trends. Furthermore, mRNA expression of carnitine palmitoyl transferase 1 (cpt1) and lipoprotein lipase (lpl) among each dietary lysolecithin treatment were significantly higher than those in the control diet (P < 0.05). In terms of inflammation, mRNA expression of tumor necrosis factor α (tnf-α) and interleukin-1 β (il-1β) were significantly down-regulated in fish fed diets with lysolecithin compared with those in the control diet (P < 0.05), while the mRNA expression of interleukin-10 (il-10) was significantly higher than that in the control diet (P < 0.05). In conclusion, dietary lysolecithin could promote the growth performance, improve hepatic lipid metabolism and regulate inflammation response in juvenile large yellow croaker, and the optimal supplement level of lysolecithin was approximately 0.4% in this study.

Serum Nitric Oxide Level Serves as a Potential Prognostic Biomarker in ACLF Patients

Background and Aim

Fewer than 50% of patients with acute-on-chronic liver failure (ACLF) recover spontaneously, and without liver transplantation, ACLF is associated with high death rates. Nitric oxide (NO) has a role in the pathogenesis of various liver disorders. We investigated if serum NO level could be used as a biomarker to predict the severity and prognosis of patients with ACLF.

Methods

Between January 2018 and September 2020, a retrospective cohort of 120 ACLF patients, as well as healthy and cirrhotic controls, was investigated. The serum NO levels were measured using a commercial ELISA kit, and Kaplan-Meier survival analysis was conducted.

Results

ACLF patients had significantly higher serum NO levels than healthy and cirrhotic controls. Multivariate analysis indicated that the serum NO level (HR=1.078, 95% CI 1.031-1.126, P<0.01), as well as the Model for End-stage Liver Disease (MELD) score, may be an affordable, easily available, and significant independent predictive marker for mortality. In ACLF patients, a serum NO level of > 53.5 μmol/L was associated with a significant increase in the risk of mortality or liver transplantation. A combination of serum NO level and MELD score to assess the severity and prognosis of ACLF patients showed enhanced performance.

Conclusion

Based on serum NO levels at the time of hospital admission, ACLF patients may be divided into high-risk and low-risk groups. The combination of serum NO level and MELD score is more closely linked to the patient's outcome than either value alone. This method might be used to evaluate patient prognoses and select candidates for liver transplantation.

Zanthoxylum armatum DC. extract induces liver injury via autophagy suppression and oxidative damage by activation of mTOR/ULK1 pathway

Zanthoxylum armatum DC. (ZADC) has anti-inflammatory, antioxidative, and antibacterial effects. The cytotoxicity of methanol extract of Zanthoxylum armatum DC. (MZADC) has been reported for BRL 3 A cell lines. However, whether MZADC can induce liver damage in vivo remains unclear. Therefore, it is essential to explore whether ZADC causes liver injury and, if the results confirm hepatotoxicity, to further study the potential mechanisms for the in-vitro cytotoxicity of the BRL 3 A cell lines. In vivo, different doses (0.346, 0.519, and 1.038 g/kg/day) of MZADC treatment were given by intragastric administration among male Sprague Dawley rats for 28 days. Levels of serum alanine transaminase (ALT), aspartate transaminase (AST), and alkaline phosphatase (ALP) in the high dose group increased. Steatosis and focal necrosis were found in liver cells in rats in the high dose group. In vitro, BRL 3 A cells were cultivated with MZADC at different concentrations (30, 50, and 70 μg/mL) for 24 h. The cell viability, the number of autophagosomes, and the expression levels of LC3 and Beclin-1 were on a decreasing trend. Besides, proportions of p-mTOR/mTOR and p-ULK1/ULK1 increased. Meanwhile, reactive oxygen species (ROS) accumulation and the content of malondialdehyde (MDA) were on the rise while the activity of superoxide dismutase (SOD) and the content of glutathione (GSH) was on the decline. This research suggests that MZADC may cause rats liver injury and inhibit autophagy in BRL 3 A cells by the mTOR/ULK1 pathway, and further induce intracellular oxidative damage.

Apoptotic bone marrow-derived mononuclear cells accelerate liver regeneration after extended resection

Objective: to compare the efficiency of regenerative processes in the liver using apoptotic bone marrow-derived mononuclear cells (BMMCs) and intact BMMCs from healthy animals on an extended liver resection (ELR) model.

Materials and methods. Male Wistar rats (n = 77) with an ELR model (70–75%) were divided into 3 groups: group 1 (control with a single intraperitoneal injection of saline), group 2 (single intraperitoneal injection of unsorted intact BMMCs at a dose of 30–35 × 106, and group 3 (single intraperitoneal injection of apoptotic BMMCs at the same dose). Restoration of biochemical parameters of liver function and mass, as well as the emerging microstructural changes in hepatocytes in histological preparations, were monitored by assessing hepatocyte mitotic activity (MA) during the first 7–10 days after ELR.

Results. It was found that in groups 2 and 3, as compared with group 1, there was no death after ELR modeling, and that the biochemical parameters of liver function normalized more rapidly (at days 10–14). Hepatocyte MA in group 3 sharply increased as early as on day 1, and mitotic index (MI) averaged 14‰, reaching 20.9‰ in some experiments; MI in the control group remained at the baseline by this time, while in group 2, MI was only 3.2‰. In group 3, liver mass recovered more rapidly after ELR to baseline values already at days 8–10, whereas the recovery was at day 12–14 and day 17–20 in group 2 and group 1, respectively. It was suggested that the more pronounced increase in the efficiency of regenerative processes in the liver after ELR in group 3 after using apoptotic BMMCs was due to the release from these cells of a large spectrum of formed paracrine factors, including various classes of RNA molecules involved in the regeneration process.

Conclusion. Apoptotic BMMNCs have a more effective adaptive and regulatory potential than intact BMMCs because reorganizations are rapidly formed in the damaged liver cells, providing an early and more powerful activation of the targeted regenerative program.

The liver in sepsis: molecular mechanism of liver failure and their potential for clinical translation

Liver failure is a life-threatening complication of infections restricting the host's response to infection. The pivotal role of the liver in metabolic, synthetic, and immunological pathways enforces limits the host's ability to control the immune response appropriately, making it vulnerable to ineffective pathogen resistance and tissue damage. Deregulated networks of liver diseases are gradually uncovered by high-throughput, single-cell resolved OMICS technologies visualizing an astonishing diversity of cell types and regulatory interaction driving tolerogenic signaling in health and inflammation in disease. Therefore, this review elucidates the effects of the dysregulated host response on the liver, consequences for the immune response, and possible avenues for personalized therapeutics.

MHBSt167 induced autophagy promote cell proliferation and EMT by activating the immune response in L02 cells

Background

Hepatitis B virus can induce hepatocellular carcinoma (HCC) by inducing a host immune response against infected hepatocytes. C-terminally truncated middle surface protein (MHBSt) has been reported to contribute to HCC through transcriptional activation in epidemiology studies, while the underlying mechanism of MHBSt-induced HCC is unknown.

Methods

In this study, a premature stop at codon 167 in MHBS (MHBSt¹⁶⁷) was investigated into eukaryotic expression plasmid pcDNA3.1(-). MHBSt¹⁶⁷ expressed plasmid was transfected into the L02 cell line, cell proliferation was analyzed by CCK-8 and high-content screening assays, the cell cycle was analyzed by flow cytometry, and epithelial-to-mesenchymal transition and autophagy were analyzed by immunoblotting and immunofluorescence. NF-κB activation and the MHBSt¹⁶⁷-induced immune response were analyzed by immunoblotting and immunofluorescence. IFN-α, IFN-β and IL-1α expression were analyzed by qPCR. Autophagy inhibitors were used to analyze the relationship between the immune response and autophagy.

Results

The results showed that MHBSt¹⁶⁷ promoted L02 cell proliferation, accelerated cell cycle progression from the S to G2 phase and promoted epithelial-to-mesenchymal transition through ER-stress, leading to autophagy and NF-κB activation and increased immune-related factor expression. The MHBSt¹⁶⁷-induced acceleration of cell proliferation and the cell cycle was abolished by autophagy or NF-κB inhibitors.

Conclusion

In summary, MHBSt¹⁶⁷ could promote cell proliferation, accelerate cell cycle progression, induce EMT and activate autophagy through ER-stress to induce the host immune response, supporting a potential role of MHBSt¹⁶⁷ in contributing to carcinogenesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12985-022-01840-z.

Impacts of conventional and biodegradable microplastics on juvenile Lates calcarifer: Bioaccumulation, antioxidant response, microbiome, and proteome alteration

Discarded plastic bag is a main component of marine debris, posing potential threats to marine biota. This study was conducted to assess the potential effects of microplastics on juvenile Lates calcarifer. Fish were exposed via diet to two microplastic types from conventional polyethylene (PE) and biodegradable (Bio) plastic bags for 21 days. Antioxidative enzymes activity, intestinal microbiome and proteome were determined. PE and Bio microplastics were found to accumulate in gastrointestinal tracts, and no mortality was observed. Microplastics exposure did not induce significant antioxidant response except for the glutathione reductase (GR) modulation. Intestinal microbiome diversity decreased significantly in PE group based on Simpson index. Both types of microplastics induced proteome modulation by down-regulating proteins associated with immune homeostasis. Bio microplastics maintained higher intestinal microbial diversity and induced more proteins alteration than PE microplastics. This study provides toxicological insights into the impacts of conventional and biodegradable microplastics on juvenile L. calcarifer.

Mouse liver injury induces hepatic macrophage FGF23 production

Fibroblast growth factor 23 (FGF23) is a bone marrow cell produced hormone that functions in the intestine and kidney to regulate phosphate homeostasis. Increased serum FGF23 is a well-established predictor of mortality in renal disease, but recent findings linking increased levels to hepatic and cardiac diseases have suggested that other organs are sources of FGF23 or targets of its effects. The potential ability of the liver to produce FGF23 in response to hepatocellular injury was therefore examined. Very low levels of Fgf23 mRNA and FGF23 protein were detected in normal mouse liver, but the amounts increased markedly during acute liver injury from the hepatotoxin carbon tetrachloride. Serum levels of intact FGF23 were elevated during liver injury from carbon tetrachloride. Chronic liver injury induced by a high fat diet or elevated bile acids also increased hepatic FGF23 levels. Stimulation of toll-like receptor (TLR) 4-driven inflammation by gut-derived lipopolysaccharide (LPS) underlies many forms of liver injury, and LPS induced Fgf23 in the liver as well as in other organs. The LPS-inducible cytokines IL-1β and TNF increased hepatic Fgf23 expression as did a TLR2 agonist Pam2CSK3. Analysis of Fgf23 expression and FGF23 secretion in different hepatic cell types involved in liver injury identified the resident liver macrophage or Kupffer cell as a source of hepatic FGF23. LPS and cytokines selectively induced the hormone in these cells but not in hepatocytes or hepatic stellate cells. FGF23 failed to exert any autocrine effect on the inflammatory state of Kupffer cells but did trigger proinflammatory activation of hepatocytes. During liver injury inflammatory factors induce Kupffer cell production of FGF23 that may have a paracrine proinflammatory effect on hepatocytes. Liver-produced FGF23 may have systemic hormonal effects as well that influence diseases in in other organs.

Activation of autophagy during normothermic machine perfusion of discarded livers is associated with improved hepatocellular function

Liver transplantation is hampered by a severe shortage of donor organs. Normothermic machine perfusion (NMP) of donor livers allows dynamic preservation in addition to viability assessment before transplantation. Little is known about the injury and repair mechanisms induced during NMP. To investigate these mechanisms, we examined gene and protein expression changes in a cohort of discarded human livers, stratified by hepatocellular function, during NMP. Six human livers acquired through donation after circulatory death (DCD) underwent 12 h of NMP. Of the six livers, three met predefined criteria for adequate hepatocellular function. We applied transcriptomic profiling and protein analysis to evaluate temporal changes in gene expression during NMP between functional and nonfunctional livers. Principal component analysis segregated the two groups and distinguished the various perfusion time points. Transcriptomic analysis of biopsies from functional livers indicated robust activation of innate immunity after 3 h of NMP followed by enrichment of prorepair and prosurvival mechanisms. Nonfunctional livers demonstrated delayed and persistent enrichment of markers of innate immunity. Functional livers demonstrated effective induction of autophagy, a cellular repair and homeostasis pathway, in contrast to nonfunctional livers. In conclusion, NMP of discarded DCD human livers results in innate immune-mediated injury, while also activating autophagy, a presumed mechanism for support of cellular repair. More pronounced activation of autophagy was seen in livers that demonstrated adequate hepatocellular function.NEW & NOTEWORTHY We demonstrate that ischemia-reperfusion injury occurs in all livers during NMP, though there are notable differences in gene expression between functional and nonfunctional livers. We further demonstrate that activation of the liver's repair and homeostasis mechanisms through autophagy plays a vital role in the graft's response to injury and may impact liver function. These findings indicate that liver autophagy might be a key therapeutic target for rehabilitating the function of severely injured or untransplantable livers.

N-linoleyltyrosine ameliorates high-fat diet-induced obesity in C57BL/6 mice via cannabinoid receptor regulation

OBJECTIVES

N-linoleyltyrosine (NITyr) showed mild effects in preclinical studies. The research discussed the effect of NITyr on a high-fat diet (HFD) induced obese (DIO) mice, and preliminarily explored its mechanism.

METHODS

The DIO mice were established by feeding an HFD for 12 weeks and subsequently administrated orally with NITyr (30, 60 and 100 mg/kg) for four weeks. The indexes of serum and liver samples were determined by ELISA kit. The pathological status of adipose and liver were detected by HE staining. The factors related to energy and lipid metabolism were measured via western blot.

RESULTS

NITyr at 60 and 100 mg/kg/day suppressed the weight gain without affecting water and food intake. Accordingly, NITyr reduced adipose weight and the area of individual adipocytes and increased the number of adipocytes. Moreover, NITyr didn't affect the appetite-related indexes such as ghrelin, peptide YY and brain-derived neurotrophic factor. Besides, NITyr didn't affect other organ coefficients except for the liver. Correspondingly, NITyr reduced alanine aminotransferase and aspartate aminotransferase levels, yet didn't influence IL-1β and TNF-α levels, and the liver injury. The levels of triacylglycerol (TG), total cholesterol (TC), glucose, insulin, adiponectin and leptin in serum were assessed to evaluate the effect of NITyr on glucose and lipid metabolism. NITyr decreased the levels of TG, TC and glucose, and didn't affect insulin, adiponectin and leptin levels. Meanwhile, NITyr up-regulated p-AMPK and the cannabinoid receptor 2 (CB₂) expressions, and down-regulated PPAR, FAS and cannabinoid receptor 1 (CB₁) expressions.Overall, NITyr suppressed lipid accumulation via improving lipid and glucose metabolism involving CB₁ and CB₂ receptors.

RORα Enhances Lysosomal Acidification and Autophagic Flux in the Hepatocytes

Lysosomes are intracellular acidic organelles with catabolic functions that contribute to the activation of autophagy. Although autophagy abnormality is associated with defects in lysosomal acidification during the progression of nonalcoholic fatty liver disease (NAFLD), the mechanisms of control of lysosomal acidification are not well understood at the molecular level. Thus, we aimed to elucidate the role of the orphan nuclear receptor retinoic acid-related orphan receptor α (RORα) in lysosomal acidification and autophagic flux, particularly in nutrition-enriched hepatocytes. First, lysosomal acidity was much lower in the hepatocytes obtained from hepatocyte-specific RORα-deleted (RORα-LKO) mice, whereas the infusion of an adenovirus encoding RORα in wild-type hepatocytes increased lysosomal acidity, as determined by LysoSensor. Second, the lysosomal translocation of the mechanistic target of rapamycin was increased and immature cathepsin D was accumulated in the liver of RORα-LKO mice. Third, the accumulation of LC3-II, p62/sequestosome 1 (SQSTM1), and neighbor of BRCA1 gene 1 (NBR1) was increased in the livers of RORα-LKO mice, indicating an impaired autophagic flux in the livers. Consistently, the number of autolysosomes containing mitochondria and lipid droplets was dramatically reduced in the RORα-deleted hepatocytes. Finally, we found that RORα induced the transcription of genes involved in lysosomal function, such as Atp6v1g1, a vacuolar H+ -ATPase (v-ATPase) subunit, which were largely down-regulated in the livers of mice with high-fat diet-induced NAFLD and patients with hepatitis. Conclusion: Targeting RORα may be a potential therapeutic strategy to restore lysosomal acidification, which inhibits the progression of NAFLD.

Carminic acid mitigates fructose-triggered hepatic steatosis by inhibition of oxidative stress and inflammatory reaction

Excessive fructose (Fru) consumption has been reported to favor nonalcoholic fatty liver disease (NAFLD). However, the molecular mechanism is still elusive, lacking effective therapeutic strategies. Carminic acid (CA), a glucosylated anthraquinone found in scale insects like Dactylopius coccus, exerts anti-tumor and anti-oxidant activities. Nevertheless, its regulatory role in Fru-induced NAFLD is still obscure. Here, the effects of CA on NAFLD in Fru-challenged mice and the underlying molecular mechanisms were explored. We found that Fru intake significantly led to insulin resistance and dyslipidemia in liver of mice, which were considerably attenuated by CA treatment through repressing endoplasmic reticulum (ER) stress. Additionally, inflammatory response induced by Fru was also attenuated by CA via the blockage of nuclear factor-κB (NF-κB), mitogen-activated protein kinases (MAPKs) and tumor necrosis factor α/TNF-α receptor (TNF-α/TNFRs) signaling pathways. Moreover, Fru-provoked oxidative stress in liver tissues was remarkably attenuated by CA mainly through improving the activation of nuclear factor erythroid 2-related factor 2 (Nrf-2). These anti-dyslipidemias, anti-inflammatory and anti-oxidant activities regulated by CA were confirmed in the isolated primary hepatocytes with Fru stimulation. Importantly, the in vitro experiments demonstrated that Fru-induced lipid accumulation was closely associated with inflammatory response and reactive oxygen species (ROS) production regulated by TNF-α and Nrf-2 signaling pathways, respectively. In conclusion, these results demonstrated that CA could be considered as a potential therapeutic strategy to attenuate metabolic disorder and NAFLD in Fru-challenged mice mainly through suppressing inflammatory response and oxidative stress.

Sex-Specific Regulation of Interferon-γ Cytotoxicity in Mouse Liver by Autophagy

BACKGROUND AND AIMS

Interferon-γ (IFNγ) is a central activator of immune responses in the liver and other organs. IFNγ triggers tissue injury and inflammation in immune diseases, which occur predominantly in females for unknown reasons. Recent findings that autophagy regulates hepatotoxicity from proinflammatory cytokines led to an examination of whether defective hepatocyte autophagy underlies sex-specific liver injury and inflammation induced by IFNγ.

APPROACH AND RESULTS

A lentiviral autophagy-related 5 (Atg5) knockdown was performed to decrease autophagy-sensitized alpha mouse liver (AML 12) hepatocytes to death from IFNγ in combination with IL-1β or TNF. Death was necrosis attributable to impaired energy homeostasis and adenosine triphosphate depletion. Male mice with decreased autophagy from a tamoxifen-inducible, hepatocyte-specific Atg5 knockout were resistant to IFNγ hepatotoxicity whereas female knockout mice developed liver injury and inflammation. Female mice had increased IFNγ-induced signal transducer and activator of transcription 1 (STAT1) levels compared to males. Blocking STAT1, but not interferon regulatory factor 1, signaling prevented IFNγ-induced hepatocyte death in autophagy-deficient AML12 cells and female mice. The mechanism of death is STAT1-induced overexpression of nitric oxide synthase 2 (NOS2) as in vitro hepatocyte death and in vivo liver injury were blocked by NOS2 inhibition.

CONCLUSIONS

Decreased hepatocyte autophagy sensitizes mice to IFNγ-induced liver injury and inflammation through overactivation of STAT1 signaling that causes NOS2 overexpression. Hepatotoxicity is restricted to female mice, suggesting that sex-specific effects of defective autophagy may underlie the increased susceptibility of females to IFNγ-mediated immune diseases.

Exosomes in Sepsis

Sepsis is a severe state of infection with high mortality. Pathogen-associated molecular patterns and damage-associated molecular patterns (DAMPs) initiate dysregulated systemic inflammation upon binding to pattern recognition receptors. Exosomes are endosome-derived vesicles, which carry proteins, lipids and nucleic acids, and facilitate intercellular communications. Studies have shown altered contents and function of exosomes during sepsis. In sepsis, exosomes carry increased levels of cytokines and DAMPs to induce inflammation. Exosomal DAMPs include, but are not limited to, high mobility group box 1, heat shock proteins, histones, adenosine triphosphate, and extracellular RNA. Exosomes released during sepsis have impact on multiple organs, including the lungs, kidneys, liver, cardiovascular system, and central nervous system. Here, we review the mechanisms of inflammation caused by exosomes, and their contribution to multiple organ dysfunction in sepsis.