Fatty acid and endotoxin activate inflammasomes in mouse hepatocytes that release danger signals to stimulate immune cells

New Evidence for the Mechanisms of Nanoplastics Amplifying Cadmium Cytotoxicity: Trojan Horse Effect, Inflammatory Response, and Calcium Imbalance

Nanoplastics (NPs) are emerging pollutants worldwide. Particularly worrisome is that although studies have reported that NPs can amplify the biotoxicity of environmental pollutants, the specific mechanism remains unclear. Here, we found that NPs, even without significant toxicity (cell survival: 99.11%), amplified the hepatocyte toxicity of Cd2+. Mechanistically, higher Cd2+ uptake (Δ = 23.80%) combined with crucial intracellular desorption behavior of Cd2+ loaded in NPs (desorption rate: 82.70%) were identified as prerequisites for NPs amplifying Cd2+ cytotoxicity. As for toxigenic pathways, the inflammatory response and calcium (Ca) signaling pathway were identified as the primary molecular events leading to the amplification of Cd2+ cytotoxicity. Further phenotypic monitoring revealed that NPs synergized with Cd2+ to induce more severe pyroptosis and apoptosis by activating the inflammatory caspase-1-dependent and Ca2+-mitochondrial-caspase-3 pathways to a greater extent, respectively. This study reveals and proves for the first time the "Trojan horse" effects of NPs, thus elucidating the actual mechanisms by which NPs act as toxicity amplifiers of pollutants, providing significant insights into accurate risk assessment of NPs in composite pollution.

High uric acid exacerbates nonalcoholic steatohepatitis through NLRP3 inflammasome and Gasdermin D-mediated pyroptosis

Hyperuricemia is independently associated with an increased risk of nonalcoholic steatohepatitis (NASH), but the underlying mechanisms responsible for this association remain unclear. We first analyzed the association between intrahepatic UA levels and gasdermin D (GSDMD)-mediated pyroptosis in vivo and in vitro. We subsequently generated hepatic-specific glucose transporter 9 (GLUT9)-knockout mice and GSDMD knockout (GSDMD-/-) mice to explore the role of intrahepatic UA in GSDMD-induced pyroptosis in NASH. We found that high intrahepatic UA levels were positively related to GSDMD-mediated pyroptosis in NASH mice. The inhibition of hepatic UA production by allopurinol alleviated hepatic inflammation and GSDMD-mediated pyroptosis in NASH mice. Hepatic-specific knockout of Glut9 significantly decreased intrahepatic UA levels, attenuated NOD-like receptor family pyrin domain containing 3 (NLRP3)-Caspase-1-GSDMD-mediated pyroptosis in hepatocytes, and ameliorated hepatic inflammation and fibrosis in different mouse models of NASH. Further experiments revealed that inhibiting the NLRP3/Caspase-1/GSDMD pathway obviously blocked UA-induced pyroptosis and inflammation in hepatocytes. Additionally, GSDMD deficiency markedly reversed hepatic inflammation and fibrosis in NASH mice. In conclusion, our results showed that high UA could induce NLRP3-Caspase1-GSDMD-mediated pyroptosis, thereby aggravating NASH in mice.

Biochemical and hematological reference intervals in rhesus and cynomolgus macaques and implications for vaccine and drug development

Nonhuman primates have a key role in the evaluation of novel therapeutics including vaccine and drug development. Monitoring biochemical and hematological parameters of macaques is critical to understand toxicity and safety, but general reference intervals following standardized guidelines remain to be determined. Here we compiled multiple internal datasets to define normal ranges of classical biochemical and hematological parameters in Indian and Chinese rhesus macaques as well as cynomolgus macaques. Furthermore, the combination of hematological data with phenotypic information of cells obtained by flow cytometry enabled analyses of specific immune cell subsets. We found that vaccination generally induced transient changes at 24 h in cell frequencies accompanied by fluctuation in selected liver enzymes and metabolites. However, most parameters remained within our identified reference intervals. These deviations did not lead to noticeable side effects. Fluctuation in selected biochemical and hematological parameters was accompanied with differentiation of CD14+CD16+ intermediate monocytes and upregulation of genes associated with interleukin-1 signaling. By contrast, two animals with noticeable side effects showed sustained deviations. This study provides insights into baseline and vaccine-induced biochemical and hematological profiles of healthy macaques, facilitating the interpretation of toxicity and safety assessments in preclinical trials of novel therapies.

Dehydrotrametenolic acid methyl ester, a triterpenoid of Poria cocos, alleviates non-alcoholic steatohepatitis by suppressing NLRP3 inflammasome activation via targeting Caspase-1 in mice

Non-alcoholic steatohepatitis (NASH) has emerged as a prevalent chronic liver disease with a huge unmet clinical need. A few studies have reported the beneficial effects of Poria cocos Wolf (P. cocos) extract on NASH mice, but the active components were still unknown. In this study we investigated the therapeutic effects of dehydrotrametenolic acid methyl ester (ZQS5029-1), a lanosterol-7,9(11)-diene triterpenes in P. cocos, in a high-fat diet plus CCl4 induced murine NASH model and a GAN diet induced ob/ob murine NASH model. The NASH mice were treated with ZQS5029-1 (75 mg·kg-1·d-1, i.g.) for 6 and 8 weeks, respectively. We showed that ZQS5029-1 treatment markedly relieved liver injury, inflammation and fibrosis in both the murine NASH models. We found that ZQS5029-1 treatment significantly suppressed hepatic NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome activation in both the NASH murine models, and blocked lipopolysaccharides (LPS)+adenosine 5'-triphosphate (ATP)/Nigericin-induced NLRP3 inflammasome activation in bone marrow-derived macrophages (BMDMs) and Kupffer cells in vitro. We demonstrated that ZQS5029-1 directly bound to the H236 residue of mouse Caspase-1, thereby inhibiting NLRP3 inflammasome activation. The effects of ZQS5029-1 on macrophage-hepatocyte/HSC crosstalk were analyzed using the supernatants from macrophages preconditioned with LPS + ATP introduced into hepatocytes and hepatic stellate cells (HSCs). We found that the conditioned medium from the BMDMs induced injury and death, as well as lipid accumulation in hepatocytes, and activation of HSCs; these effects were blocked by conditioned medium from BMDMs treated with ZQS5029-1. Moreover, the protective effects of ZQS5029-1 on hepatocytes and HSCs were eliminated by H236A-mutation of Caspase-1. We conclude that ZQS5029-1 is a promising lead compound for the treatment of NASH by inhibiting NLRP3 inflammasome activation through targeting Caspase-1 and regulating the macrophage-hepatocyte/HSC crosstalk.

Molecular mechanisms of pyroptosis in non-alcoholic steatohepatitis and feasible diagnosis and treatment strategies

Pyroptosis is a distinct form of cell death that plays a critical role in intensifying inflammatory responses. It primarily occurs via the classical pathway, non-classical pathway, caspase-3/6/7/8/9-mediated pathways, and granzyme-mediated pathways. Key effector proteins involved in the pyroptosis process include gasdermin family proteins and pannexin-1 protein. Pyroptosis is intricately linked to the onset and progression of non-alcoholic steatohepatitis (NASH). During the development of NASH, factors such as pyroptosis, innate immunity, lipotoxicity, endoplasmic reticulum stress, and gut microbiota imbalance interact and interweave, collectively driving disease progression. This review analyzes the molecular mechanisms of pyroptosis and its role in the pathogenesis of NASH. Furthermore, it explores potential diagnostic and therapeutic strategies targeting pyroptosis, offering new avenues for improving the diagnosis and treatment of NASH.

Network Pharmacology and Experimental Validation of the Effects of Shenling Baizhu San, Quzhi Ruangan Fang and Gexia Zhuyu Tang on the Intestinal Flora of Rats with NAFLD

Objective

In this study, we investigated the effect of Shenling Baizhu San(SLBZS), Quzhi Ruangan Fang(QZRGF) and Gexia Zhuyu Tang(GXZYT) on the intestinal flora of NAFLD rats through network pharmacology and experimental validation.

Materials and Methods

Protein-protein interaction, Gene Ontology (GO), and molecular docking were performed. Male Sprague-Dawley (SD) rats were divided into 6 groups: Normal, Model, SLBZS (7.2g/kg), QZRGF (27.72g/kg), GXZYT (28.8 g/kg) and positive control (Fenofibrate, 18mg/kg); the NAFLD model was established by High-fat diet. After one week of acclimatisation feeding consecutively, continuous gavage was given for 8 W and 12 W. Serum, liver and faeces were collected and biochemical and pathological indices were determined. The diversity and abundance of intestinal flora were also analyzed using 16S rDNA amplified sequencing.

Results

A total of 132 active ingredients were obtained from the screening results of SLBZS. A total of 202 active ingredients were obtained from the screening results of GXZYT. The screening results of QZRGF obtained 34 active ingredients. Nine common hub genes were screened from the PPI network. GO functional analysis reported that these targets were mainly closely related to the response to bacterial molecules. The molecular docking results indicated that the 11 core constituents in three compound prescriptions has good binding ability with MAPK1, AKT1, CASP3, FOS, TP53, STAT3, MAPK3.

Conclusion

The Chinese herbal compounds SLBZS, QZRGF and GXZYT may exert lipid-lowering effects through multi-components, multi-targets and multi-methods for the treatment of NAFLD while improving the diversity and abundance of the intestinal flora of the rats, and the best effect was achieved with SLBZS.

NLRP3 inflammasome in health and disease (Review)

Activation of inflammasomes is the activation of inflammation‑related caspase mediated by the assembly signal of multi‑protein complex and the maturity of inflammatory factors, such as IL‑1β and IL‑18. Among them, the Nod‑like receptor family pyrin domain containing 3 (NLRP3) inflammasome is the most thoroughly studied type of inflammatory corpuscle at present, which is involved in the occurrence and development of numerous human diseases. Therefore, targeting the NLRP3 inflammasome has become the focus of drug development for related diseases. In this paper, the research progress of the NLRP3 inflammasome in recent years is summarized, including the activation and regulation of NLRP3 and its association with diseases. A deep understanding of the regulatory mechanism of NLRP3 will be helpful to the discovery of new drug targets and the development of therapeutic drugs.

A guide to pathophysiology, signaling pathways, and preclinical models of liver fibrosis

Liver fibrosis is potentially a reversible form of liver disease that evolved from the early stage of liver scarring as a consequence of chronic liver injuries. Recurrent injuries in the liver without any appropriate medication cause the injuries to get intense and deeper, which gradually leads to the progression of irreversible cirrhosis or carcinoma. Unfortunately, there are no approved treatment strategies for reversing hepatic fibrosis, making it one of the significant risk factors for developing advanced liver disorders and liver disease-associated mortality. Consequently, the interpretation of the fundamental mechanisms, etiology, and pathogenesis is crucial for identifying the potential therapeutic target as well as evaluating novel anti-fibrotic therapy. However, despite innumerable research, the functional mechanism and disease characteristics are still obscure. To accelerate the understanding of underlying disease pathophysiology, molecular pathways and disease progression mechanism, it is crucial to mimic human liver disease through the formation of precise disease models. Although various in vitro and in vivo liver fibrotic models have emerged and developed already, a perfect clinical model replicating human liver diseases is yet to be established, which is one of the major challenges in discovering proper therapeutics. This review paper will shed light on pathophysiology, signaling pathways, preclinical models of liver fibrosis, and their limitations.

CD36-mediated uptake of oxidized LDL induces double-negative regulatory T cell ferroptosis in metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Metabolic alterations have been shown to instigate liver inflammation in metabolic dysfunction-associated steatotic liver disease (MASLD), but the underlying mechanism is not fully elucidated. During MASLD progression, intrahepatic CD3+TCRαβ+CD4-CD8- double negative T regulatory cells (DNT) decrease cell survival and immunosuppressive function, leading to aggravated liver inflammation. In this study, we aim to reveal the underlying mechanisms that cause changes in DNT during MASLD progression.

METHODS

The correlation of serum oxidized low-density lipoprotein (oxLDL) levels and DNT from patients with MASLD and MASLD mouse models were evaluated. The mechanisms of oxLDL affecting DNT survival and function were explored through transcriptome sequencing analysis, flow cytometry, and CUT & TAG experiments.

RESULTS

Serum oxLDL levels are negative correlated with survival and functional molecule expression of circulating DNT in patients with MASLD and intrahepatic DNT in MASLD mouse models. Mechanistically, oxLDL increases DNT CD36 expression through the NF-κB pathway, leading to enhanced uptake of oxLDL and subsequent occurrence of ferroptosis and functional impairment. oxLDL enhances ferroptosis in DNT by upregulating acyl-CoA synthetase long chain family member 4 expression. By transferring CD36-/- DNT into MASLD mice, we observe a significant reduction in ferroptosis and improved immune regulation in CD36-/- DNT compared to wild type DNT. This improvement in DNT results in a notable enhancement of therapeutic efficacy against MASLD.

CONCLUSION

oxLDL induces a decline in the survival and immune regulatory function of DNT, subsequently weakening their role in maintaining liver immune homeostasis in MASLD. Specific targeting of CD36 to prevent ferroptosis in DNT may provide a novel therapeutic approach for the treatment of MASLD.

Ginsenoside Rg1: A bioactive therapeutic agent for diverse liver diseases

Diverse liver diseases are characterised by late diagnosis and rapid progression and have become one of the major threats to human health. To delay the transition from benign tissue lesions to a substantial organ injury, scientists have gradually applied natural compounds derived from plants as a complementary therapy in the field of hepatology. Ginseng (Panax ginseng C. A. Meyer) is a tonic traditional Chinese herbal medicine, and natural products, including ginsenoside Rg1 (G-Rg1), which is a kind of 20(S)-protopanaxatriol saponin with a relatively high biological activity, can be isolated from the roots or stems of ginseng. Given these information, this review aimed to summarise and discuss the metabolic mechanisms of G-Rg1 in the regulation of diverse liver diseases and the measures to improve its bioavailability. As a kind of monomer in Chinese medicine with multitarget pharmacological effects, G-Rg1 can provide significant therapeutic benefits in the alleviation of alcoholic liver disease, nonalcoholic fatty liver disease, liver fibrosis, viral hepatitis, etc., which mainly rely on the inhibition of apoptosis, strengthening endogenous anti-inflammatory and antioxidant mechanisms, activation of immune responses and regulation of efflux transport signals, to improve pathological changes in the liver caused by lipid deposition, inflammation, oxidative stress, accumulation of hepatotoxic product, etc. However, the poor bioavailability of G-Rg1 must be overcome to improve its clinical application value. In summary, focusing on the hepatoprotective benefits of G-Rg1 will provide new insights into the development of natural Chinese medicine resources and their pharmaceutical products to target the treatment of liver diseases.

Smad4 deficiency in hepatocytes attenuates NAFLD progression via inhibition of lipogenesis and macrophage polarization

Nonalcoholic fatty liver disease (NAFLD), a major cause of chronic liver disorders, has become a serious public health issue. Although the Smad4 signaling pathway has been implicated in the progression of NAFLD, the specific role of Smad4 in hepatocytes in NAFLD pathogenesis remains unclear. Hepatocyte-specific knockout Smad4 mice (AlbSmad4-/-) were first constructed using the Cre-Loxp recombinant system to establish a high-fat diet induced NAFLD model. The role of Smad4 in the occurrence and development of NAFLD was determined by monitoring the body weight of mice, detecting triglycerides and free fatty acids in serum and liver tissue homogenates, staining the tissue sections to observe the accumulation of liver fat, and RT-qPCR detecting the expression of genes related to lipogenesis, fatty acid intake, and fatty acid β oxidation. The molecular mechanism of Smad4 in hepatocytes affecting NAFLD was therefore investigated through combining in vitro and in vivo experiments. Smad4 deficiency in hepatocytes mitigated NAFLD progression and decreased inflammatory cell infiltration. Moreover, Smad4 deficiency inhibited CXCL1 secretion by suppressing the activation of the ASK1/P38/JNK signaling pathway. Furthermore, targeting CXCL1 using CXCR2 inhibitors diminished hepatocyte lipogenesis and inhibited the polarization of M1-type macrophages. Collectively, these results suggested that Smad4 plays a vital role in exacerbating NAFLD and may be a promising candidate for anti-NAFLD therapy.

Dual role of pyroptosis in liver diseases: mechanisms, implications, and therapeutic perspectives

Pyroptosis, a form of programmed cell death induced by inflammasome with a mechanism distinct from that of apoptosis, occurs via one of the three pathway types: classical, non-classical, and granzyme A/B-dependent pyroptosis pathways. Pyroptosis is implicated in various diseases, notably exhibiting a dual role in liver diseases. It facilitates the clearance of damaged hepatocytes, preventing secondary injury, and triggers immune responses to eliminate pathogens and damaged cells. Conversely, excessive pyroptosis intensifies inflammatory responses, exacerbates hepatocyte damage and promotes the activation and proliferation of hepatic stellate cells, accelerating liver fibrosis. Furthermore, by sustaining an inflammatory state, impacts the survival and proliferation of cancer cells. This review comprehensively summarizes the dual role of pyroptosis in liver diseases and its therapeutic strategies, offering new theoretical foundations and practical guidance for preventing and treating of liver diseases.

Hepatocellular CMPK2 promotes the development of metabolic dysfunction-associated steatohepatitis

BACKGROUND & AIMS

There are limited pharmacological treatment options for metabolic dysfunction-associated steatohepatitis (MASH), the progressive form of metabolic dysfunction-associated steatotic liver disease (MASLD). Therefore, we aimed to identify novel therapeutic targets.

METHODS

The Gene Expression Omnibus database and human liver tissues obtained from patients with MASH were used to identify differentially expressed genes in MASH. The functional role of cytidine/uridine monophosphate kinase 2 (CMPK2) was assessed in mice with hepatocyte-specific overexpression, conditional knockout mice, and several murine MASH models. CMPK2 inhibitors were discovered through surface plasmon resonance imaging coupled with indirect enzyme activity detection.

RESULTS

CMPK2, a critical enzyme involved in mitochondrial DNA synthesis, exhibited significant upregulation in the livers of obese individuals with MASH and mice with diet-induced MASH. Hepatocyte-specific Cmpk2 deletion substantially mitigated liver injury, inflammation, and fibrosis in mice. Inhibition of CMPK2, either through genetic manipulation or pharmacological intervention with nordihydroguaiaretic acid, suppressed Nlrp3 (NOD-like receptor family pyrin domain containing 3) inflammasome activation and subsequent hepatic pyroptosis. Furthermore, nordihydroguaiaretic acid alleviated diet-induced metabolic disorders, inflammation, and fibrosis in vivo.

CONCLUSIONS

These findings establish CMPK2 as a critical mediator in the progression from metabolic dysfunction-associated steatotic liver to MASH and highlight its potential as a therapeutic target for metabolic diseases.

IMPACT AND IMPLICATIONS

Cytidine/uridine monophosphate kinase 2 (CMPK2) is upregulated in the metabolic dysfunction-associated steatohepatitis (MASH) stage but not in the early stages of metabolic dysfunction-associated steatotic liver disease. Our study demonstrated that diet-induced MASH phenotypes, including liver injury, inflammation, and fibrosis were alleviated in hepatocyte-specific Cmpk2-knockout mice. These findings suggest that CMPK2 serves as a critical link in the progression of steatotic liver to steatohepatitis, offering novel mechanistic insights into MASH development. Furthermore, this discovery identified CMPK2 as a promising target for the development of therapeutic drugs for MASH.

Progress in the Study of Intratumoral Microorganisms in Hepatocellular Carcinoma

The intratumoral microbiota, an integral part of liver tumors, has garnered significant attention from researchers due to its role in tumor development regulation and impact on cancer treatment. Intratumoral microorganism not only influences tumorigenesis and progression, but also serves as potential biomarkers and targets for tumor therapy. Targeted manipulation of these microorganisms holds great promise for personalized liver cancer treatment. However, there is a lack of systematic summaries and reports on the study of intratumoral microorganism in hepatocellular carcinoma. This comprehensive review aims to address this gap by summarizing research progress related to in the field of hepatocellular carcinoma intratumoral bacteria, including their sources, types, distribution characteristics within tumors, impact on tumor development, underlying mechanisms, and application prospects. Through the analysis, it is proposed that intratumor organisms can be used as markers for liver cancer diagnosis and treatment, drug carrier materials for targeting liver cancer tissues, and the research prospects of developing new combination therapies based on the in-depth understanding of the interactions between intratumor microorganisms and the tumor microenvironment, immune cells, liver cancer cells, etc. as well as exploring the prospects of developing new combination therapies based on these interactions. It is hoped that from the perspective of intratumoral microbiota, potential theoretical support can be provided for future research on targeted cancer therapy for liver cancer intratumoral microbiota, and new insights and ideas can be provided for targeting points and research methods in tumor research.

Exposure to triphenyl phosphate during pregnancy: The role of gut-bile acids-liver axis on lipid metabolism in male offspring

The widespread use of Triphenyl phosphate (TPhP) as a substitute flame retardant in various commercial products has raised global concerns for its health risks. Previously, we found that gestational and lactational TPhP exposure disturbed lipid metabolism and gut microbiota in offspring sex-dependently. In this study, we further explored the prenatal TPhP exposure on lipid metabolism in male offspring, and the role of gut-bile acids-liver axis in it. The results showed that gestational TPhP exposure would induce hyperlipidemia in male offspring, it dose-dependently increased the weight of body and liver, levels of serum lipid, and enlarged lipid droplets in white adipose tissue. The expression of lipid metabolism-related genes was significantly changed in the liver and adipose tissue. The gut microbiome of male offspring was also altered, with different profiles between the low and high dose treatment group. Target bile acids (BAs) metabolites analysis revealed a significant increased levels of primary BAs cholic acid (CA), but decreased levels of chenodeoxycholic acid (CDCA), and decreased levels of the secondary BAs deoxycholic acid (DCA), hyodeoxycholic acid (HDCA), ursodeoxycholic acid (UDCA), and lithocholic acid (LCA) in TPhP treatment group. Measurements of gene expression along the gut-BAs-liver axis showed that the TPhP treatment group had an increase in cholesterol-7alpha-hydroxylase (CYP7A1) and a decrease in apical sodium-dependent bile acid transporter (ASBT), with only the low-dose group exhibiting an increase in carbohydrate response element binding protein (ChREBP). Correlation and mediation analysis highlighted associations of Burkholderiaceae in low-dose treatment group and Erysipelotrichaceae in high dose group with lipid metabolism and BAs metabolites. No consistent correlations were observed in two treatment group. Additionally, Mantel tests did not reveal a consistent correlation between the microbiome network community and lipid metabolism or the gut-bile acids-liver axis. Overall, our findings indicate that gestational TPhP exposure induces hyperlipidemia in male offspring, and while the gut-BAs-liver axis plays a role, other mechanisms warrant further investigation.

Benzo(a)pyrene and Gut Microbiome Crosstalk: Health Risk Implications

This review delves into the impact of benzo(a)pyrene (B(a)P), which is a toxic and pervasive polycyclic aromatic hydrocarbon (PAH) and known carcinogen, on the human health risk from a gut microbiome perspective. We retrieved the relevant articles on each PAH and summarized the reporting to date, with a particular focus on benzo(a)pyrene, which has been reported to have a high risk of gut microbiome-related harm. B(a)P exposure can compromise the homeostasis of the gut microbiota, leading to dysbiosis, a state of microbial imbalance. The consequences of B(a)P-induced gut dysbiosis can be far-reaching, potentially contributing to inflammation, metabolic disorders, and an increased risk of various diseases. Additionally, due to the strong coupling between B(a)P and microparticles, the toxicity of B(a)P may be further compounded by its reaction with strong gut disruptors such as micro-/nanoplastics, which have recently become a serious environmental concern. This review summarizes current research on the impact of B(a)P on the gut microbiome, highlighting the intricate relationship between environmental exposure, gut health, and human disease. Further research is necessary to elucidate the underlying mechanisms and develop effective strategies to mitigate the adverse health effects of B(a)P exposure.

Fanlian Huazhuo Formula: A promising herbal preparation for metabolic liver disease

The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) has increased significantly in recent decades and is projected to increase further due to the rising obesity rates. MASLD patients are at higher risk of developing advanced liver diseases "cirrhosis and hepatocellular carcinoma" as well as liver- or cardiovascular-related mortality. Existing lipid-lowering therapies failed to reduce the risk of mortality in these patients. Therefore, there is an urgent need for pharmacotherapies that can control and even reverse this disease. Fanlian Huazhuo Formula (FLHZF) is a combination herbal preparation, and its various individual constituents regulate hepatic lipid metabolism, adipose tissue inflammation, and gut microbiota. Despite, these useful effects, limited information is available on its benefits in diet-induced hepatosteatosis. In this article, we discuss the research findings recently published about the therapeutic effects of FLHZF in suppressing MASLD development and underlying mechanisms. Utilizing a series of in vitro and in vivo experiments, the authors demonstrated for the first time that FLHZF suppresses MASLD in male mice possibly by inhibiting hepatic de novo lipogenesis pathways and reducing hepatocyte death. This study paves the way for future investigations aimed at investigating FLHZF's role in inhibiting lipogenesis particularly using radioactively-labeled glucose and acetate, and governing hepatocyte mitochondrial function, gut microbiome profile, and its effects in other models of MASLD, and female mice.

Immunological dynamics in MASH: from landscape analysis to therapeutic intervention

Metabolic dysfunction-associated steatohepatitis (MASH), previously known as nonalcoholic steatohepatitis (NASH), is a multifaceted liver disease characterized by inflammation and fibrosis that develops from simple steatosis. Immune and inflammatory pathways have a central role in the pathogenesis of MASH, yet, how to target immune pathways to treat MASH remains perplexed. This review emphasizes the intricate role that immune cells play in the etiology and pathophysiology of MASH and highlights their significance as targets for therapeutic approaches. It discusses both current strategies and novel therapies aimed at modulating the immune response in MASH. It also highlights challenges in liver-specific drug delivery, potential off-target effects, and difficulties in targeting diverse immune cell populations within the liver. This review is a comprehensive resource that integrates current knowledge with future perspectives in the evolving field of MASH, with the goal of driving forward progress in medical therapies designed to treat this complex liver disease.

Targeting gut microbiota and metabolism profiles with coated sodium butyrate to ameliorate high-energy and low-protein diet-induced intestinal barrier dysfunction in laying hens

High energy diets are a risk factor for intestinal barrier damage. Butyrate, a major energy source for intestinal epithelial cells, has been shown to improve barrier dysfunction and modulate the gut microbiota. In this trial, we examined the preventative effect of coated sodium butyrate (CSB) on high-energy and low-protein (HELP)-induced intestinal barrier injury in laying hens, and also worked to determine the underlying mechanisms by an integrative analysis of gut microbiota and the metabolome. A total of 216 healthy 28-week-old Huafeng laying hens were randomly assigned to 3 groups with 6 replicates each: the CON group (normal diet), HELP group (HELP diet) and CH500 group (500 mg/kg CSB added to HELP diet). The duration of the trial encompassed a period of 10 weeks. The results revealed that CSB treatment improved the laying rate and mitigated the detrimental effects on intestinal barrier function and the inflammatory response induced by the HELP diet in laying hens (P < 0.05). Microbial profiling analysis revealed that the CSB treatment reshaped the HELP-perturbed gut microbiota and promoted the growth of beneficial bacteria (P < 0.05). Untargeted metabolomics analysis revealed that CSB reduced the metabolites associated with intestinal inflammation (P < 0.05). In conclusion, CSB did not merely modulate alterations in the gut microbiota composition and microbial metabolites but also yielded increased egg production, while mitigating intestinal barrier dysfunction and inflammatory responses induced by HELP in laying hens.

Azithromycin induces liver injury in mice by targeting the AMPK/Nrf2 pathway

BACKGROUND

Azithromycin is an antibacterial and anti-inflammatory drug widely used for the treatment of various diseases, including those caused by atypical pathogens, bacterial or viral infections, chronic sinusitis, and bronchial asthma, particularly in pediatric patients. However, concerns have emerged regarding its hepatotoxicity and its precise mechanism of action remains unclear.

OBJECTIVE

To investigate the molecular mechanisms responsible for azithromycin-induced acute liver injury to advance our understanding of the progression and pathogenesis of antibiotic-induced liver damage, and to improve prevention and treatment strategies.

MATERIALS AND METHODS

C57BL/6 mice, Nrf2-/- mice, and primary hepatocytes were used. Primary hepatocytes from mice were isolated using a two-step perfusion method and cultured in vitro via the 'sandwich' culture model.

RESULTS

The exposure to azithromycin resulted in increased apoptosis and reactive oxygen species (ROS) levels. In mouse models, intraperitoneal administration of azithromycin at varying concentrations and time points substantially induced hepatic disarray, swelling, and dysfunction. Azithromycin markedly upregulated the mRNA and protein levels of phosphorylated adenosine-activated protein kinase (AMPK) while downregulating nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), and NADPH: quinone oxidoreductase 1 (NQO-1). Moreover, HO-1 and NQO-1 protein levels remained largely unaffected in primary hepatocytes co-cultured with azithromycin in Nrf2-/- mice.

CONCLUSIONS

Our findings suggest that azithromycin-induced acute liver injury is mediated by suppression of Nrf2 activation and ROS production. This sheds light on the potential mechanisms involved in azithromycin-induced liver damage, underscoring the importance of exploring targeted interventions to mitigate the hepatotoxic effects.

Novel Choline-Deficient and 0.1%-Methionine-Added High-Fat Diet Induces Burned-Out Metabolic-Dysfunction-Associated Steatohepatitis with Inflammation by Rapid Immune Cell Infiltration on Male Mice

Background: Metabolic-dysfunction-associated steatotic liver disease (MASLD) is a progressive liver disorder that possesses metabolic dysfunction and shows steatohepatitis. Although the number of patients is globally increasing and many clinical studies have developed medicine for MASLD, most of the studies have failed due to low efficacy. One reason for this failure is the lack of appropriate animal disease models that reflect human MASLD to evaluate the potency of candidate drugs. Methods: We developed a novel choline-deficient and 0.11%-methionine-added high-fat diet (CDAHFD)-based (MASH) diet that can induce murine metabolic-dysfunction-associated steatohepatitis (MASH) without severe body weight loss. We performed kinetic analyses post-feeding and proposed an appropriate timing of MASH pathogenesis by quantitatively analyzing steatosis, inflammation, and fibrosis. Results: This MASH diet induced liver fibrosis earlier than the conventional CDAHFD model. In brief, lipid accumulation, inflammation, and fibrosis started after 1 week from feeding. Lipid accumulation increased until 8 weeks and declined thereafter; on the other hand, liver fibrosis showed continuous progression. Additionally, immune cells, especially myeloid cells, specifically accumulated and induced inflammation in the initiation stage of MASH. Conclusions: The novel MASH diet promotes the dynamics of lipid deposition and fibrosis in the liver, similar to human MASH pathophysiology. Furthermore, immune-cell-derived inflammation possibly contributes to the initiation of MASH pathogenesis. We propose this model can be the new pre-clinical MASH model to discover the drugs against human MASH by evaluating the interaction between parenchymal and non-parenchymal cells.

Microbiota-derived succinic acid mediates attenuating effect of dietary tomato juice supplementation on steatohepatitis through enhancing intestinal barrier

The hepatoprotective potential of tomato juice (TJ) has been reported in chronic liver models, and its potential prebiotic properties may be key to its preventative effects. However, the mechanistic role of the gut microbiota and its derived metabolites in ameliorating nonalcoholic steatohepatitis (NASH) via TJ remains unclear. In this study, we explored how TJ regulates gut microbiota and succinic acid (SA) to restore intestinal barrier function and thus suppress NASH progression. TJ supplementation effectively reduced serum lipid concentrations, alleviated endotoxin levels, and suppressed activation of the endotoxin-TLR4-NF-κB pathway in methionine-choline-deficient (MCD) diet-induced NASH mice. TJ restored the MCD diet-induced gut microbiota dysbiosis, increased the abundance of short-chain fatty acid and SA-producing bacteria (Bifidobacterium, Ileibacterium, Odoribacter, and Parasutterella) and enhanced the expression of intestinal barrier-associated proteins (E-cadherin, Claudin-1, MUC-2, and ZO-1). The hepatoprotective and enteroprotective effects of TJ were abolished in an antibiotic-treated mouse model, underscoring the pivotal role of the gut microbiota in the beneficial effects of TJ on NASH. Fecal metabolomics demonstrated that TJ significantly upregulated the tricarboxylic acid cycle, pyruvate metabolism, and butanoate metabolism pathways, increasing levels of butyric acid (BA) and SA-metabolites associated with reduced hepatic steatosis and intestinal damage. We further found that the physiological concentration of SA, rather than BA, could reduce pro-inflammatory cytokines (TNF-α and IL-6) levels and enhance mucin proteins and tight junction markers in the LPS-induced colon cell line LS174T. This study uncovers new mechanisms by which TJ prevents NASH, highlighting the potential of TJ and SA as effective dietary supplements for patients with chronic liver diseases.

Inflammasomes in chronic liver disease: Hepatic injury, fibrosis progression and systemic inflammation

Chronic liver disease leads to hepatocellular injury that triggers a pro-inflammatory state in several parenchymal and non-parenchymal hepatic cell types, ultimately resulting in liver fibrosis, cirrhosis, portal hypertension and liver failure. Thus, an improved understanding of inflammasomes - as key molecular drivers of liver injury - may result in the development of novel diagnostic or prognostic biomarkers and effective therapeutics. In liver disease, innate immune cells respond to hepatic insults by activating cell-intrinsic inflammasomes via toll-like receptors and NF-κB, and by releasing pro-inflammatory cytokines (such as IL-1β, IL-18, TNF-α and IL-6). Subsequently, cells of the adaptive immune system are recruited to fuel hepatic inflammation and hepatic parenchymal cells may undergo gasdermin D-mediated programmed cell death, termed pyroptosis. With liver disease progression, there is a shift towards a type 2 inflammatory response, which promotes tissue repair but also fibrogenesis. Inflammasome activation may also occur at extrahepatic sites, such as the white adipose tissue in MASH (metabolic dysfunction-associated steatohepatitis). In end-stage liver disease, flares of inflammation (e.g., in severe alcohol-related hepatitis) that spark on a dysfunctional immune system, contribute to inflammasome-mediated liver injury and potentially result in organ dysfunction/failure, as seen in ACLF (acute-on-chronic liver failure). This review provides an overview of current concepts regarding inflammasome activation in liver disease progression, with a focus on related biomarkers and therapeutic approaches that are being developed for patients with liver disease.

Co-exposure to different bacterial species' lipopolysaccharides with the NASH diet exacerbates NASH and liver fibrosis progression in mice

BACKGROUND AND AIM

With the obesity epidemic, nonalcoholic fatty liver disease (NAFLD) has become a public health concern, but its progression mechanism remains unclear. Experimental models mimicking human NAFLD/steatohepatitis (NASH) are crucial. This study simulates gut microbiota imbalance effects on NASH and liver fibrosis.

METHODS

We used different bacterial sources of lipopolysaccharide (LPS), including Escherichia coli (GEC) and Salmonella abortus equi (GSE), combined with a Gubra Amylin NASH (GAN) diet to induce NASH and liver fibrosis.

RESULTS

The GSE group showed significantly higher serum alanine aminotransferase, hydroxyproline, CD68-positive cells, α-smooth muscle actin, glial fibrillary acidic protein, and TNF-α, COL1A1, TGF-β, and NLRP3 expressions compared to the the GAN group. The GSE group also had higher Erysipelotrichaceae, Akkermansiaceae, and Bacteroidaceae family numbers.

CONCLUSIONS

The GAN diet with LPS treatment successfully induced NASH and fibrosis making this model useful for preclinical NASH drug testing.

Liver Transplantation: A Test of Cellular Physiology, Preservation, and Injury

Liver transplantation has evolved into a mature clinical field, but scarcity of usable organs poses a unique challenge. Expanding the donor pool requires novel approaches for protecting hepatic physiology and cellular homeostasis. Here we define hepatocellular injury during transplantation, with an emphasis on modifiable cell death pathways as future therapeutics.

Role of MMP-2 and MMP-9 in the Relationship between Inflammation, Fibrosis, and Apoptosis during Progression of Non-Alcoholic Fatty Liver Disease and Diagnostic Significance of Plasma Levels of Their Active Forms

MMP-2 and MMP-9 play an important role in pathogenesis of chronic liver diseases, participating in the processes of inflammation and fibrosis. Their role in progression of non-alcoholic fatty liver disease (NAFLD) is poorly understood. Analysis of MMP-2, -9 levels in the blood plasma of patients with different forms of NAFLD [liver steatosis (LS) and non-alcoholic steatohepatitis (NASH) of weak (-WA), moderate (MA), high (-HA) activity without pronounced fibrosis] was performed. Correlations between the levels of MMP-2, -9 and mRNA of the genes MMP2, MMP9, ADAM17, NLRP3, caspase 3 activity in peripheral blood leukocytes (PBL), TNFα, IL-6, sIL-6R, cytokeratin-18 fragments in plasma were assessed. In steatosis, the levels of MMP2 gene mRNA in PBL and MMP-2 in plasma are lower than in the control, and expression of the NLRP3 gene in PBL is increased relative to other groups. In the NASH-WA, the level of MMP-9 is higher than in the control, in LS, and in NASH-MA, which could be associated with activation of inflammation during transformation of LS into NASH. The plasma level of MMP-9 over 389.50 pg/ml has been shown to be diagnostically significant for identification of NASH-WA among the patients with steatosis (AUC ROC = 0.818, 95% CI = 0.689-0.948, p < 0.001). In NAFLD, the level of MMP-9 could be associated not only with inflammation, but also with apoptosis. ADAM17 probably plays a certain role in this regard. In the advanced NASH, hepatocyte apoptosis is increased, the level of caspase 3 activity in PBL is increased, the level of MMP-9 in the blood is reduced to the level of the control and LS. In the NASH-HA, the level of mRNA of the ADAM17 gene in PBL is increased compared to the control, NASH-WA, and NASH-MA. Thus, MMP-2 and MMP-9 are involved in pathogenesis of NAFLD already at the early stages and their level in blood could be associated with the presence and severity of inflammation in the liver parenchyma.

The beneficial impact of curcumin on cardiac lipotoxicity

Lipotoxicity is defined as a prolonged metabolic imbalance of lipids that results in ectopic fat distribution in peripheral organs such as the liver, heart, and kidney. The harmful consequences of excessive lipid accumulation in cardiomyocytes cause cardiac lipotoxicity, which alters the structure and function of the heart. Obesity and diabetes are linked to lipotoxic cardiomyopathy. These anomalies might be caused by a harmful metabolic shift that accumulates toxic lipids and shifts glucose oxidation to less fatty acid oxidation. Research has linked fatty acids, fatty acyl coenzyme A, diacylglycerol, and ceramide to lipotoxic stress in cells. This stress can be brought on by apoptosis, impaired insulin signaling, endoplasmic reticulum stress, protein kinase C activation, p38 Ras-mitogen-activated protein kinase (MAPK) activation, or modification of peroxisome proliferator-activated receptors (PPARs) family members. Curcuma longa is used to extract curcumin, a hydrophobic polyphenol derivative with a variety of pharmacological characteristics. Throughout the years, curcumin has been utilized as an anti-inflammatory, antioxidant, anticancer, hepatoprotective, cardioprotective, anti-diabetic, and anti-obesity drug. Curcumin reduces cardiac lipotoxicity by inhibiting apoptosis and decreasing the expression of apoptosis-related proteins, reducing the expression of inflammatory cytokines, activating the autophagy signaling pathway, and inhibiting the expression of endoplasmic reticulum stress marker proteins.

Hepatic stearoyl-CoA desaturase-1 deficiency induces fibrosis and hepatocellular carcinoma-related gene activation under a high carbohydrate low fat diet

Stearoyl-CoA desaturase-1 (SCD1) is a pivotal enzyme in lipogenesis, which catalyzes the synthesis of monounsaturated fatty acids (MUFA) from saturated fatty acids, whose ablation downregulates lipid synthesis, preventing steatosis and obesity. Yet deletion of SCD1 promotes hepatic inflammation and endoplasmic reticulum stress, raising the question of whether hepatic SCD1 deficiency promotes further liver damage, including fibrosis. To delineate whether SCD1 deficiency predisposes the liver to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC), we employed in vivo SCD1 deficient global and liver-specific mouse models fed a high carbohydrate low-fat diet and in vitro established AML12 mouse cells. The absence of liver SCD1 remarkably increased the saturation of liver lipid species, as indicated by lipidomic analysis, and led to hepatic fibrosis. Consistently, SCD1 deficiency promoted hepatic gene expression related to fibrosis, cirrhosis, and HCC. Deletion of SCD1 increased the circulating levels of Osteopontin, known to be increased in fibrosis, and alpha-fetoprotein, often used as an early marker and a prognostic marker for patients with HCC. De novo lipogenesis or dietary supplementation of oleate, an SCD1-generated MUFA, restored the gene expression related to fibrosis, cirrhosis, and HCC. Although SCD1 deficient mice are protected against obesity and fatty liver, our results show that MUFA deprivation results in liver injury, including fibrosis, thus providing novel insights between MUFA insufficiency and pathways leading to fibrosis, cirrhosis, and HCC under lean non-steatotic conditions.

The pharmacological management of alcohol-related cirrhosis: what's new?

INTRODUCTION

Alcohol use disorder (AUD) is present in the majority of patients with alcohol-associated liver disease (ALD), which leads to about 50% of cirrhosis-related hospitalizations and over 25% of deaths worldwide. Patients with ALD often present at an advanced stage, like cirrhosis with its complications and alcohol-associated hepatitis (AH), which has high short-term mortality. Current treatments are limited, with the limited benefit of glucocorticoids only in the short-term among patients with AH, highlighting an urgent need for novel therapies.

AREAS COVERED

This review applies the PIRO (Predisposition, Injury, Response, Organ dysfunction) concept to ALD, understanding an ongoing process of liver damage, and opportunities to address and halt the progression. We also highlight the significance of treating AUD to improve long-term outcomes in ALD.

EXPERT OPINION

Personalized therapies targeting specific genetic profiles and multiple pathogenic pathways are crucial in managing ALD. Emerging therapies like gut-liver-brain axis modulators like fecal microbiota transplant and probiotics, interleukin-22, granulocyte-colony stimulating factor (G-CSF) and stem cells, epigenetic regulators of inflammation and regeneration are encouraging with the potential of efficacy in patients with ALD. Liver transplantation (LT) is a definitive therapy for advanced cirrhosis with increasing impetus on early LT select patients with active alcohol use.

Targeting cell death in NAFLD: mechanisms and targeted therapies

Nonalcoholic fatty liver disease (NAFLD) is a group of chronic liver disease which ranges from simple steatosis (NAFL) to non-alcoholic steatohepatitis (NASH) and is characterized by lipid accumulation, inflammation activation, fibrosis, and cell death. To date, a number of preclinical studies or clinical trials associated with therapies targeting fatty acid metabolism, inflammatory factors and liver fibrosis are performed to develop effective drugs for NAFLD/NASH. However, few therapies are cell death signaling-targeted even though the various cell death modes are present throughout the progression of NAFLD/NASH. Here we summarize the four types of cell death including apoptosis, necroptosis, pyroptosis, and ferroptosis in the NAFLD and the underlying molecular mechanisms by which the pathogenic factors such as free fatty acid and LPS induce cell death in the pathogenesis of NAFLD. In addition, we also review the effects of cell death-targeted therapies on NAFLD. In summary, our review provides comprehensive insight into the roles of various cell death modes in the progression of NAFLD, which we hope will open new avenues for therapeutic intervention.

Association of systemic immune biomarkers with metabolic dysfunction-associated steatotic liver disease: a cross-sectional study of NHANES 2007-2018

Objective

Numerous studies emphasize the pivotal role of inflammation in metabolic dysfunction-associated steatotic liver disease (MASLD) development. Some link specific systemic immune biomarkers (e.g., systemic immuno-inflammatory index [SII], neutrophil-to-albumin ratio [NPAR] and neutrophil-to-lymphocyte ratio [NLR]) to hepatic steatosis risk. However, the relevance of other markers like systemic immune-inflammation index [SIRI], platelet-to-lymphocyte ratio [PLR] and lymphocyte/monocyte ratio [LMR] in MASLD remains unclear. Limited literature covers all six markers together. This study aims to investigate the association between SII, SIRI, LMR, NLR, PLR, and NPAR and MASLD, assessing their predictive value.

Methods

In this cross-sectional analysis of adults from NHANES (2007-2018), we investigated the relationship between six systemic immune biomarkers, stratified by quartiles: quartile1 (Q1), quartile2 (Q2), quartile3 (Q3) and quartile4 (Q4), and the outcome of MASLD assessed by Fatty Liver Index (FLI) and United States Fatty Liver Index (USFLI). Logistic regression and restricted cubic splines (RCS) were employed to assess the association between systemic immune biomarkers and MASLD risks. Propensity score matching controlled for potential confounders, and receiver operating characteristic (ROC) curve analysis evaluated the biomarkers' predictive performances for MASLD. Subgroup and interaction analysis were conducted to explore the effects of systemic immune biomarkers on MASLD risks. Multicollinearity was quantified using the variance inflation factor.

Results

In total, 14,413 participants were included and 6,518 had MASLD. Compared with non-MASLD, participants with MASLD had higher SII, SIRI, NLR, PLR, and NPAR (p < 0.001). SII, SIRI, NLR, and NPAR were further validated in the restricted cubic splines (RCS) regression model and identified as positive linear relationships (p for nonlinear >0.05). The prevalence of MASLD increased with the Q4 of SII [OR = 1.47, 95%CI (1.24, 1.74)], SIRI [OR = 1.30, 95%CI (1.09, 1.54)], NLR [OR = 1.25, 95%CI (1.04, 1.49)], PLR [OR = 1.29, 95%CI (1.09, 1.53)] and NPAR [OR = 1.29, 95%CI (1.09, 1.54)] compared to the Q1 after adjusting for the bias caused by potential confounders. However, the propensity score matching analysis only supported an association between the highest SII, SIRI, NLR NPAR and the risk of MASLD. The results of the subgroup analysis showed considerable robustness in the relationship.

Conclusion

Higher SII, SIRI, NLR and NPAR were positively associated with a heightened risk of MASLD. NPAR showed the superior predictive value, followed by SII, SIRI and NLR. This needs to be validated in additional longitudinal studies and clinical trials.

Immune infiltration analysis based on pyroptosis-related gene in metabolic dysfunction-associated fatty liver disease

Introduction

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a prevalent chronic disease that can involve pyroptosis. The primary objective of this study was to conduct a thorough and comprehensive analysis the pyroptosis-related genes in MAFLD.

Methods

We identified pyroptosis-related differentially expressed genes (PRDEGs) in both healthy individuals and MAFLD patients. Using various bioinformatic approaches, we conducted an immune infiltration analysis from multiple perspectives.

Results

A total of 20 pyroptosis-related LASSO genes were obtained, and 10 hub genes were used to do immune infiltration analysis. The hub genes were utilized in the construction of interaction networks between mRNA-miRNA and mRNA-TF. Immune characteristics analysis revealed multiple immune cell types significantly related to PRDEG expression, particularly genes HSP90AA1, TSLP, CDK9, and BRD4.

Conclusion

Pyroptosis-related immune infiltration might be a mechanism of MAFLD progression and offers a research direction for potential treatment techniques.

Nanoformulations for the diagnosis and treatment of metabolic dysfunction-associated steatohepatitis

Metabolic dysfunction-associated steatohepatitis (MASH) is a progressive phase of metabolic dysfunction-associated steatotic liver disease (MASLD) that develops into irreversible liver cirrhosis and hepatocellular carcinoma, ultimately necessitating liver transplantation as the sole life-saving option. However, given the drawbacks of liver transplantation, including invasiveness, chronic immunosuppression, and a lack of donor livers, prompt diagnosis and effective treatment are indispensable. Due to the limitations of liver biopsy and conventional imaging modalities in diagnosing MASH, as well as the potential hazards associated with liver-protecting medicines, numerous nanoformulations have been created for MASH theranostics. Particularly, there has been significant study interest in artificial nanoparticles, natural biomaterials, and bionic nanoparticles that exhibit exceptional biocompatibility and bioavailability. In this review, we summarized extracellular vesicles (EVs)-based omics analysis and Fe3O4-based functional magnetic nanoparticles as magnetic resonance imaging (MRI) contrast agents for MASH diagnosis. Additionally, artificial nanoparticles such as organic and inorganic nanoparticles, as well as natural biomaterials such as cells and cell-derived EVs and bionic nanoparticles including cell membrane-coated nanoparticles, have also been reported for MASH treatment owing to their specific targeting and superior therapeutic effect. This review has the potential to stimulate advancements in nanoformulation fabrication techniques. By exploring their compatibility with cell biology, it could lead to the creation of innovative material systems for efficient theragnostic uses for MASH. STATEMENT OF SIGNIFICANCE: People with metabolic dysfunction-associated steatohepatitis (MASH) will progress to fibrosis, cirrhosis, or even liver cancer. It is imperative to establish effective theragnostic techniques to stop MASH from progressing into a lethal condition. In our review, we summarize the advancement of artificial, natural, and bionic nanoparticles applied in MASH theragnosis. Furthermore, the issues that need to be resolved for these cutting-edge techniques are summarized to realize a more significant clinical impact. We forecast the key fields that will advance further as nanotechnology and MASH research progress. Generally, our discovery has significant implications for the advancement of nanoformulation fabrication techniques, and their potential to be compatible with cell biology could lead to the creation of innovative materials systems for effective MASH theragnostic.

Honey vesicle-like nanoparticles protect aged liver from non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH), an advanced form of non-alcoholic fatty liver disease (NAFLD), has emerged as the leading cause of liver failure and related death. Currently, no medication is specifically approved to treat NAFLD or NASH. Here we report that oral administration of honey vesicle-like nanoparticles (H-VLNs) to naturally aged mice protects the liver from NASH development. H-VLNs are dominantly taken up by Kupffer cells in the liver and suppress hepatic chronic inflammation and further development of fibrosis and nodule formation in aged mice. Besides their reported anti-inflammasome function, H-VLNs are found to inhibit the transcriptional activities of C-JUN and nuclear factor-kappa B (NF-κB). MicroRNAs miR5119 and miR5108 and phenolic compound luteolin in H-VLNs are identified in suppressing both the C-JUN and NF-κB pathways. Collectively, oral intake of H-VLNs represents a promising new user-friendly modality to prevent the development of NASH.

The Coptidis Rhizoma and Bovis Calculus herb pair attenuates NASH and inhibits the NLRP3 inflammasome activation

The Coptidis Rhizoma and Bovis Calculus herb pair possesses clearing heat and detoxifying effects. The aim of this study was to reveal the effects and mechanisms of the herb pair in the treatment of NASH by network pharmacology and experimental verification. A network pharmacology-based approach was employed to predict the putative mechanism of the herb pair against NASH. The high-fat diet (HFD) and methionine/choline deficient (MCD) diet induced NASH models were used to evaluate efficacy and mechanism of the herb pair. Network pharmacological analysis showed that the herb pair modulated NOD-like receptor pathway. In the HFD mice, herb pair reduced body weight, blood sugar, serum ALT, AST, TBA, TC, TG and LDL-C contents, also improved the general morphology and pathological manifestations. Hepatic transcriptomics study showed that herb pair attenuated NASH by regulating NOD-like receptor signaling pathway. Western blotting showed that herb pair reduced the protein expression levels of NLRP3, cleaved Caspase-1 and cleaved IL-1β. In the MCD mice, herb pair also reduced serum ALT, ALT and TBA levels, improved liver pathological manifestations, inhibited the protein expression levels of NLRP3, cleaved Caspase-1 and cleaved IL-1β. Our findings proved that the Coptidis Rhizoma and Bovis Calculus herb pair attenuates NASH through suppression of NLRP3 inflammasome activation. This will demonstrate effective pharmacological evidence for the clinical application of herb pair.

Dietary inflammatory index and the risks of non-alcoholic fatty liver disease: a systematic review and meta-analysis

Background

Previous studies have suggested a correlation between dietary inflammatory potential and non-alcoholic fatty liver disease (NAFLD). Therefore, the study aimed to investigate the association between dietary inflammatory potential, measured by the dietary inflammation index (DII), and NAFLD.

Methods

From establishing the database to June 2023, a systematic search of PubMed, Web of Science, Embase and Cochrane Library were performed to identify relevant observational studies. These studies reported a correlation between DII and NAFLD. The meta-analysis used odds ratio (OR) with 95% confidence intervals (CI) to evaluate the relationship between DII and NAFLD.

Results

Eight studies were included in this meta-analysis after excluding irrelevant records. A summary of the results from the included studies showed that the risk of NAFLD was higher in those exposed to higher DII (OR = 1.26, 95%CI 1.12 to 1.40, p < 0.001), with a high degree of heterogeneity (I2 = 85.7%, p < 0.001). When DII was divided into 3 tertiles from low to high for comparison, the results showed that the risk of NAFLD was higher in Tertile 2 (T2) population compared to the Tertile 1 (T1) population (OR = 1.75, 95%CI 1.20 to 2.54, p < 0.005). The risk of NAFLD was significantly higher in Tertile 3 (T3) compared to the T1 population (OR = 3.07, 95%CI 1.63 to 5.77, p = 0.001).

Conclusion

The results suggest that high DII is associated with an increased risk of NAFLD, and conversely, low DII is associated with a decreased risk of NAFLD.

Systematic Review Registration

The study complies with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and is registered on PROSPERO (CRD42023455013).

Suppression of STK39 weakens the MASLD/MASH process by protecting the intestinal barrier

STK39 is reportedly a critical negative regulator of intestinal barrier. Pharmacological targeting of STK39 is expected to protect the intestinal barrier and thereby weaken metabolic dysfunction-associated steatohepatitis (MASH); Proximal colon biopsy tissues from patients with metabolic dysfunction-associated steatotic liver disease (MASLD) and those without MASLD were analyzed for STK39 expression. Wildtype (WT) mice and systemic STK39 gene knockout (STK39-/-) male mice were fed a normal diet or a high-fat methionine-choline deficient diet (HFMCD) for 8 weeks. The MASH mice were grouped and treated with ZT-1a (a STK39 inhibitor) or vehicle intraperitoneal injection during the procedure of HFMCD induction. Liver and intestinal tissues were collected for further examination; Colon tissues from patients with MASLD exhibited higher levels of STK39 than those from subjects without MASLD. Knockout of STK39 diminished CD68+ Kupffer cells and α-SMA+ hepatic stellate cells infiltration in mouse MASH model. Treatment with ZT-1a also prevented severe steatohepatitis in a mouse MASH model, including milder histological and pathological manifestations (lobular inflammation and fibrosis) in the liver. Interestingly, Inhibition of STK39 had minimal effects on hepatic lipid metabolism. The reduced liver injury observed in mice with STK39 inhibition was linked to significant decreases in mucosal inflammation, tight junction disruption and intestinal epithelial permeability to bacterial endotoxins; Collectively, we have revealed that inhibiting STK39 prevents the progression of MASH by protecting the intestinal epithelial barrier.

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

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

NLRP3 inflammasome: a key player in the pathogenesis of life-style disorders

Proinflammatory cytokines and chemokines play a crucial role in regulating the inflammatory response, which is essential for the proper functioning of our immune system. When infections or threats to the body's defense mechanisms are detected, the innate immune system takes the lead. However, an excessive inflammatory response can lead to the production of high concentrations of cytotoxic molecules, resulting in tissue damage. Inflammasomes are significant contributors to innate immunity, and one of the most extensively studied inflammasome complexes is NOD-like receptor 3 (NLRP3). NLRP3 has a wide range of recognition mechanisms that streamline immune activation and eliminate pathogens. These cytosolic multiprotein complexes are composed of effector, adaptor, and sensor proteins, which are crucial for identifying intracellular bacterial breakdown products and initiating an innate immune cascade. To understand the diverse behavior of NLRP3 activation and its significance in the development of lifestyle-related diseases, one must delve into the study of the immune response and apoptosis mediated by the release of proinflammatory cytokines. In this review, we briefly explore the immune response in the context of lifestyle associated disorders such as obesity, hyperlipidemia, diabetes, chronic respiratory disease, oral disease, and cardiovascular disease.

Protective effects of dopamine against non-alcoholic steatohepatitis via inhibiting p65 pathways in vivo and in vitro

Introduction

Currently, the role and mechanism of dopamine in non-alcoholic steatohepatitis (NASH) remains unclear.

Methods

In vitro experiments utilized FFA and LPS to establish NASH cell models, while a fibrotic cell model was created using TGFβ1 to investigate the impact of dopamine on cellular lipid metabolism, inflammation, and fibrosis. In vivo experiments involved the use of MCD and HFD diets to induce NASH in mouse models for observing the effects of dopamine on NASH disease progression.

Results

Our study showed that dopamine significantly downregulated the expression levels of Caspase 1, IL-1β and IL18 in the HepG2 NASH cell model. In addition, dopamine could inhibit the TGF-β1-induced accumulation of collagen I and α-SMA in LX2 cells. In vivo experiments have shown that dopamine attenuation in mice is associated with MCD diet-induced and HFD-induced steatohepatitis. Mechanically, dopamine inhibits the p65 signaling pathway in NASH.

Conclusion

In conclusion, the present study demonstrates the role of dopamine in ameliorating the symptoms of NASH and provides a direction for future research on the application of the dopaminergic system to liver disease.

Association Between Bowel Wall Thickening and Long-Term Outcomes in Decompensated Liver Cirrhosis

INTRODUCTION

Bowel wall thickening is commonly observed in liver cirrhosis, but few studies have explored its impact on the long-term outcomes of patients with cirrhosis.

METHODS

Overall, 118 patients with decompensated cirrhosis were retrospectively enrolled, in whom maximum wall thickness of small bowel, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum could be measured in computed tomography (CT) images. X-tile software was employed to determine the best cut-off values of each segment of bowel wall thickness for predicting the risk of further decompensation and death. Cumulative rates of further decompensation and death were calculated by Nelson-Aalen cumulative risk curve analyses. Predictors of further decompensation and death were evaluated by competing risk analyses. Sub-distribution hazard ratios (sHRs) were calculated.

RESULTS

Cumulative rates of further decompensation were significantly higher in patients with wall thickness of ascending colon ≥ 11.7 mm (P = 0.014), transverse colon ≥ 3.2 mm (P = 0.043), descending colon ≥ 9.8 mm (P = 0.035), and rectum ≥ 7.2 mm (P = 0.045), but not those with wall thickness of small bowel ≥ 8.5 mm (P = 0.312) or sigmoid colon ≥ 7.1 mm (P = 0.237). Wall thickness of ascending colon ≥ 11.7 mm (sHR = 1.70, P = 0.030), transverse colon ≥ 3.2 mm (sHR = 2.15, P = 0.038), and rectum ≥ 7.2 mm (sHR = 2.38, P = 0.045) were independent predictors of further decompensation, but not wall thickness of small bowel ≥ 8.5 mm (sHR = 1.19, P = 0.490), descending colon ≥ 9.8 mm (sHR = 1.53, P = 0.093) or sigmoid colon ≥ 7.1 mm (sHR = 0.63, P = 0.076). Small bowel, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum wall thickness were not significantly associated with death.

CONCLUSIONS

Colorectal wall thickening, but not small bowel wall, may be considered for the prediction of further decompensation in cirrhosis.

Dietary milk polar lipids modulate gut barrier integrity and lipid metabolism in C57BL/6J mice during systemic inflammation induced by Escherichia coli lipopolysaccharide

The focus of this work is the role milk polar lipids play in affecting gut permeability, systemic inflammation, and lipid metabolism during acute and chronic inflammation induced by a single subcutaneous injection of lipopolysaccharide. Three groups of C57BL/6J mice were fed: modified AIN-93G diet with moderate level of fat (CO); CO with milk gangliosides (GG); CO with milk phospholipids (MPL). The MPL did not prevent a gut permeability increase upon LPS stress but increased the expression of tight junction proteins zonula occludens-1 and occludin in colon mucosa. The GG prevented the gut permeability increase upon LPS stress. The MPL decreased absolute and relative liver mass and decreased hepatic gene expression of acetyl-CoA carboxylase 2 and 3-hydroxy-3-methylglutaryl-CoA reductase. The GG increased hepatic gene expression of acetyl-CoA acyltransferase 2. In conclusion, milk GG protected the intestinal barrier integrity but had little effect on systemic inflammation and lipid metabolism; milk MPL, conversely, had complex effects on gut permeability, did not affect systemic inflammation, and had beneficial effect on hepatic lipid metabolism.

Gut microbiota in MAFLD: therapeutic and diagnostic implications

Metabolic dysfunction-associated fatty liver disease (MAFLD), formerly known as nonalcoholic fatty liver disease, is becoming a significant contributor to chronic liver disease globally, surpassing other etiologies, such as viral hepatitis. Prevention and early treatment strategies to curb its growing prevalence are urgently required. Recent evidence suggests that targeting the gut microbiota may help treat and alleviate disease progression in patients with MAFLD. This review aims to explore the complex relationship between MAFLD and the gut microbiota in relation to disease pathogenesis. Additionally, it delves into the therapeutic strategies targeting the gut microbiota, such as diet, exercise, antibiotics, probiotics, synbiotics, glucagon-like peptide-1 receptor agonists, and fecal microbiota transplantation, and discusses novel biomarkers, such as microbiota-derived testing and liquid biopsy, for their diagnostic and staging potential. Overall, the review emphasizes the urgent need for preventive and therapeutic strategies to address the devastating consequences of MAFLD at both individual and societal levels and recognizes that further exploration of the gut microbiota may open avenues for managing MAFLD effectively in the future.

The effect of microbiome therapy on COVID-19-induced gut dysbiosis: A narrative and systematic review

AIMS

Emerging evidence highlights the role of COVID-19 in instigating gut dysbiosis, with repercussions on disease severity and bidirectional gut-organ communication involving the lung, heart, brain, and liver. This study aims to evaluate the efficacy of probiotics, prebiotics, synbiotics, and fecal microbiota transplantation (FMT) in addressing gut dysbiosis associated with COVID-19, as well as their impact on related disease severity and clinical outcomes.

MATERIALS AND METHODS

We systematically review 27 studies exploring the efficacy of different microbiome-modulating therapies: probiotics, prebiotics, synbiotics, and fecal microbiota transplantation as potential interventions for COVID-19.

KEY FINDINGS

The probiotics and synbiotics investigated encompassed a spectrum of eight bacterial and fungal genera, namely Lactobacillus, Bifidobacterium, Streptococcus, Enterococcus, Pediococcus, Bacillus, Saccharomyces, and Kluyveromyces. Noteworthy prebiotics employed in these studies included chestnut tannin, galactooligosaccharides, fructooligosaccharides, xylooligosaccharide, and resistant dextrin. The majority of the investigated biotics exhibited positive effects on COVID-19 patients, manifesting in symptom alleviation, inflammation reduction, and notable decreases in mortality rates. Five studies reported death rates, showing an average mortality ranging from 0 % to 11 % in the intervention groups, as compared to 3 % to 30 % in the control groups. Specifically, probiotics, prebiotics, and synbiotics demonstrated efficacy in diminishing the duration and severity of symptoms while significantly accelerating viral and symptomatic remission. FMT emerged as a particularly effective strategy, successfully restoring gut microbiota and ameliorating gastrointestinal disorders.

SIGNIFICANCE

The insights gleaned from this review significantly contribute to our broader comprehension of the therapeutic potential of biotics in addressing COVID-19-related gut dysbiosis and mitigating secondary multi-organ complications.

Hedan tablet ameliorated non-alcoholic steatohepatitis by moderating NF-κB and lipid metabolism-related pathways via regulating hepatic metabolites

Non-alcoholic steatohepatitis (NASH) is a severe form of fatty liver disease. If not treated, it can lead to liver damage, cirrhosis and even liver cancer. However, advances in treatment have remained relatively slow, and there is thus an urgent need to develop appropriate treatments. Hedan tablet (HDP) is used to treat metabolic syndrome. However, scientific understanding of the therapeutic effect of HDP on NASH remains limited. We used HDP to treat a methionine/choline-deficient diet-induced model of NASH in rats to elucidate the therapeutic effects of HDP on liver injury. In addition, we used untargeted metabolomics to investigate the effects of HDP on metabolites in liver of NASH rats, and further validated its effects on inflammation and lipid metabolism following screening for potential target pathways. HDP had considerable therapeutic, anti-oxidant, and anti-inflammatory effects on NASH. HDP could also alter the hepatic metabolites changed by NASH. Moreover, HDP considerable moderated NF-κB and lipid metabolism-related pathways. The present study found that HDP had remarkable therapeutic effects in NASH rats. The therapeutic efficacy of HDP in NASH mainly associated with regulation of NF-κB and lipid metabolism-related pathways via arachidonic acid metabolism, glycine-serine-threonine metabolism, as well as steroid hormone biosynthesis.

Linking fatty liver diseases to hepatocellular carcinoma by hepatic stellate cells

Hepatic stellate cells (HSCs), a distinct category of non-parenchymal cells in the liver, are critical for liver homeostasis. In healthy livers, HSCs remain non-proliferative and quiescent. However, under conditions of acute or chronic liver damage, HSCs are activated and participate in the progression and regulation of liver diseases such as liver fibrosis, cirrhosis, and liver cancer. Fatty liver diseases (FLD), including nonalcoholic (NAFLD) and alcohol-related (ALD), are common chronic inflammatory conditions of the liver. These diseases, often resulting from multiple metabolic disorders, can progress through a sequence of inflammation, fibrosis, and ultimately, cancer. In this review, we focused on the activation and regulatory mechanism of HSCs in the context of FLD. We summarized the molecular pathways of activated HSCs (aHSCs) in mediating FLD and their role in promoting liver tumor development from the perspectives of cell proliferation, invasion, metastasis, angiogenesis, immunosuppression, and chemo-resistance. We aimed to offer an in-depth discussion on the reciprocal regulatory interactions between FLD and HSC activation, providing new insights for researchers in this field.

Lipotoxicity and immunometabolism in ischemic acute kidney injury: current perspectives and future directions

Dysregulated lipid metabolism is implicated in the pathophysiology of a range of kidney diseases. The specific mechanisms through which lipotoxicity contributes to acute kidney injury (AKI) remain poorly understood. Herein we review the cardinal features of lipotoxic injury in ischemic kidney injury; lipid accumulation and mitochondrial lipotoxicity. We then explore a new mechanism of lipotoxicity, what we define as "immunometabolic" lipotoxicity, and discuss the potential therapeutic implications of targeting this lipotoxicity using lipid lowering medications.