Hepatocyte Inflammation Research Articles

Rosehip (Rosa rugosa Thunb.) ethanol extract ameliorates liver fibrosis through upregulation of the PPAR signaling pathway

The objective of this study was to examine the effect of rosehip (Rosa rugosa Thunb.) ethanol extract (RRE) on liver fibrosis in mice and the underlying molecular mechanisms. RRE has no acute oral toxicity, and the MTD in mice is 46.14 g/kg. Histopathological analysis showed that RRE significantly ameliorated inflammation, necrosis, and apoptosis of hepatocytes and collagen deposition caused by CCl4. Further assays indicated that RRE significantly suppressed the production of MDA while markedly increasing the levels of SOD and GSH in the liver. The AST, ALT, IL-6, IL-1β, TNF-α, HA, LN, PCIII, and IVC levels in serum were decreased by RRE. Transcriptome analysis shows that RRE significantly upregulates the PPAR signaling pathway. The RT-q PCR results further confirmed the RRE up-regulating Pparγ, Rxrα, and Plin5 in the PPAR signaling pathway. The Western blot and immunohistochemical results indicate that RRE upregulated PPARγ, RXRα, and Perilipin 5 while downregulating α-SMA and COL1A1 expression. The results indicate that RRE can ameliorate liver fibrosis in mice by upregulating the PPAR signaling pathway.

Diammonium glycyrrhizinate ameliorates alcohol-induced liver injury by reducing oxidative stress, steatosis, and inflammation

Alcohol-induced liver injury (ALI) is a serious global health issue. Diammonium glycyrrhizinate (DG), a pharmaceutical form of glycyrrhizic acid, has been reported to have anti-inflammatory and anti-oxidative stress properties. We investigated the potential hepatoprotective effects of DG against ALI and explored the mechanisms of it. In vivo, C57BL/6J mice were used to investigate the protective effect of DG on ALI induced by chronic plus binge alcohol exposure. In vitro, AML-12 cells were applied to evaluate the role of DDX5 in the hepatic protection of DG and explore the possible mechanism of STAT1 activation regulated by DDX5. The results showed that DG significantly alleviated liver injury, inflammation, and lipid deposition in hepatocytes. It also beneficially influenced oxidative stress dysregulation. RNA-seq expression in mouse liver tissue indicated that Dead-box helicase 5 (DDX5) might be a potential target of DG. Compared with the control group, the expression of DDX5 decreased significantly in the ethanol-fed group, while DDX5 was restored in the DG treatment group. In addition, the protective effects of DG against ALI were impaired by DDX5 deficiency. DDX5 inhibited the phosphorylation of signal transducer and activator of transcription 1 (STAT1) by recruiting the protein inhibitor of activated STAT1 (PIAS1) to STAT1. The protective effect of DG against ALI associated with oxidative stress, steatosis, and inflammation was probably via regulating the DDX5/STAT1 axis.

Thyroid Hormone-Mediated Selective Autophagy and Its Implications in Countering Metabolic Dysfunction-Associated Steatotic Liver Disease.

The influence of thyroid hormone (TH) on liver metabolism has attracted the attention of pharmacologists seeking new treatments for metabolic dysfunction-associated steatotic liver disease (MASLD), an increasingly common metabolic disorder. In this context, the selective induction of autophagy by TH in preclinical models has been identified as a promising mechanism. In this process, TH clears intrahepatic fat through lipophagy while protecting against inflammation and mitochondrial damage in hepatocytes via mitophagy. Furthermore, TH-induced aggrephagy may represent a protective mechanism to mitigate the development of MASLD-associated hepatocellular carcinoma. Considering the defects in autophagy observed during the progression of human MASLD, the induction of autophagy by TH, its metabolites, and its analogs represent a novel strategy to combat hepatic damage across the MASLD spectrum.

Loss of adipose ATF3 promotes adipose tissue lipolysis and the development of MASH

The crosstalk between adipose tissue and the liver is finely controlled to maintain metabolic health. Yet, how adipose tissue controls toxic free fatty acid overflow into the liver remains incompletely understood. Here, we show that adipocyte activating transcription factor 3 (ATF3) was induced in human or mouse obesity. Adipocyte Atf3−/− (Atf3Adi−/−) mice developed obesity, glucose intolerance, and metabolic dysfunction-associated steatohepatitis (MASH) in chow diet, high-fat diet, or Western diet-fed mice. Blocking fatty acid flux by inhibiting hepatocyte CD36, but not the restoration of hepatic AMPK signaling, prevented the aggravation of MASH in Atf3Adi−/− mice. Further studies show that the loss of adipocyte ATF3 increased lipolysis via inducing adipose triglyceride lipase, which in turn induced lipogenesis and inflammation in hepatocytes. Moreover, Atf3Adi−/− mice had reduced energy expenditure and increased adipose lipogenesis and inflammation. Our data demonstrate that adipocyte ATF3 is a gatekeeper in counteracting MASH development under physiological and pathological conditions.

Interactions between feed protein source and feeding frequency on growth performance and health status of largemouth bass (Micropterus salmoides).

In order to evaluate the effects of the interaction between different proteins and feeding frequency on largemouth bass (Micropterus salmoides) and to provide scientific guidance for the application of novel proteins and the corresponding optimal feeding strategy, a two-factorial design (5 × 3) with five protein feeds (fishmeal (FM), Clostridium autoethanogenum protein (CAP), Tenebrio molitor (TM), Chlorella meal (ChM), cottonseed protein concentrate (CPC)), and three feeding frequency (1, 2, and 3 times/d; FF1, FF2, FF3) was designed in culturing largemouth bass (initial weight, 2.98 ± 0.22g/fish) for 8weeks. Z-score combined with cluster analysis was used to analyze and compare the effects of different treatments on different indicators, such as growth performance, feed utilization, antioxidant capacity, and immune response to draw a general picture of the relationship among all these massive biomarkers. The results showed that different protein sources and feeding frequencies had significant interactive effects on growth performance, feed utilization efficiency, body lipid, and health status of largemouth bass. Fish fed with ChM feed showed similar performance to that in FM group, implying its potential for complete replacement of fishmeal in largemouth bass. Fish fed with CAP, TM, and CPC feeds showed worse performance compared to FM and ChM groups, characterized by poor growth and feed utilization, enhanced stress, chronic inflammation, and varying symptoms of histological changes in the liver and intestine, which demonstrated the adverse effects of the complete replacement of fishmeal by these three proteins. In terms of feeding frequency, fish fed with FM feed in FF3 group led to liver hypertrophy, fat accumulation, and the risk of fatty liver, while inducing liver inflammation. In addition, the TM and CAP group had the higher expression levels of inflammatory factors at FF3 group, which displayed that the interactions between FM, CAP, TM feeds and feeding frequency at FF3 might aggravate the occurrence of liver inflammation and oxidative damage of hepatocytes. Overall, FF2 had higher feed efficiency, protein efficiency, antioxidant enzyme and lysozyme activities, lower MDA content, and lower gene expression of inflammatory cytokines and could be considered as the optimum feeding frequency for largemouth bass fed with different protein feeds.

Palmitic acid causes hepatocyte inflammation by suppressing the BMAL1-NAD+-SIRT2 axis.

Palmitic acid is the most abundant saturated fatty acid in circulation and causes hepatocyte toxicity and inflammation. As saturated fatty acid can also disrupt the circadian rhythm, the present work evaluated the connection between clock genes and NAD+ dependent Sirtuins in protecting hepatocytes from lipid-induced damage. Hepatocytes (immortal cells PH5CH8, hepatoma cells HepG2) treated with higher doses of palmitic acid (400-600μM) showed typical features of steatosis accompanied with growth inhibition and increased level of inflammatory markers (IL-6 IL-8, IL-1α and IL-1β) together with decline in NAD+ levels. Palmitic acid treated hepatocytes showed significant decline in not only the protein levels of SIRT2 but also its activity as revealed by the acetylation status of its downstream targets (Tubulin and NF-ƙB). Additionally, the circadian expression of both SIRT2 and BMAL1 was inhibited in presence of palmitic acid in only the non-cancerous hepatocytes, PH5CH8 cells. Clinical specimens obtained from subjects with NASH-associated fibrosis, ranging from absent (F0) to cirrhosis (F4), showed a significant decline in levels of SIRT2 and BMAL1, especially in the cirrhotic liver. Ectopic expression of BMAL1 or activating SIRT2 by supplementation with nicotinamide riboside (precursor of NAD+) dampened the palmitic acid induced lipoinflammation and lipotoxicity more effectively in PH5CH8 cells as compared to HepG2 cells. Mechanistically, palmitic acid caused transcriptional suppression of SIRT2 by disrupting the chromatin occupancy of BMAL1 at its promoter site. Overall, the work suggested that SIRT2 is a clock-controlled gene that is transcriptionally regulated by BMAL1. In conclusion the activation of the BMAL1-NAD+-SIRT2 axis shows hepatoprotective effects by preventing lipotoxicity and dampening inflammation.

Overexpression of DTX1 inhibits D-GalN/TNF-α-induced pyroptosis and inflammation in hepatocytes by regulating NLRP3 ubiquitination.

Acute liver injury (ALI) is characterized by massive hepatocyte death and has high mortality and poor prognosis. Hepatocyte pyroptosis plays a key role in the pathophysiology of ALI and is involved in the inflammatory response mediated by NOD-like receptor protein 3 (NLRP3) inflammasome activation. Deltex 1 (DTX1) is a single transmembrane protein with ubiquitin E3 ligase activity and is closely involved in cell growth, differentiation, and apoptosis, as well as intracellular signal transduction. However, little is known about the influence of DTX1 on ALI. This study aimed to investigate the role of DTX1 in pyroptosis and inflammation induced by D-galactosamine (D-GalN) and tumor necrosis factoralpha (TNF-α) in human hepatocytes (LO2 cells) in vitro. Cell pyroptosis was measured by flow cytometry. The levels of DTX1, pyroptosis-associated proteins, and inflammatory cytokines were detected by quantitative real-time polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay. Immunofluorescence staining, co-immunoprecipitation, ubiquitination, and luciferase reporter and chromatin immunoprecipitation assays were performed to detect the regulation between DTX1 and NLRP3 or hepatocyte nuclear factor 4 alpha (HNF4α). Analysis of variance was performed to compare groups. We found that DTX1 was decreased in D-GalN/TNF-α-induced LO2 cells. DTX1 overexpression significantly inhibited D-GalN/TNF-α-induced cell pyroptosis and inflammation. DTX1 interacted with NLRP3 and induced NLRP3 ubiquitination and degradation. Furthermore, by targeting NLRP3, DTX1 knockdown significantly induced cell pyroptosis and inflammation. In addition, HNF4α promoted DTX1 transcription by binding with its promoter. Our study revealed that DTX1 suppressed D-GalN/TNF-α-induced hepatocyte pyroptosis and inflammation by regulating NLRP3 ubiquitination.

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

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

Detecting altered hepatic lipid oxidation by MRI in an animal model of MASLD

Metabolic dysfunction-associated steatotic liver disease (MASLD) prevalence is increasing annually and affects over a third of US adults. MASLD can progress to metabolic dysfunction-associated steatohepatitis (MASH), characterized by severe hepatocyte injury, inflammation, and eventual advanced fibrosis or cirrhosis. MASH is predicted to become the primary cause of liver transplant by 2030. Although the etiology of MASLD/MASH is incompletely understood, dysregulated fatty acid oxidation is implicated in disease pathogenesis. Here, we develop a method for estimating hepatic β-oxidation from the metabolism of [D15]octanoate to deuterated water and detection with deuterium magnetic resonance methods. Perfused livers from a mouse model of MASLD reveal dysregulated hepatic β-oxidation, findings that corroborate invivo imaging. The high-fat-diet-induced MASLD mouse studies indicate that decreased β-oxidative efficiency in the fatty liver could serve as an indicator of MASLD progression. Furthermore, our method provides a clinically translatable imaging approach for determining hepatic β-oxidation efficiency.

Deacetylation of HnRNP U mediated by sirtuin1 ameliorates aged rat with liver fibrosis via inhibiting p53-related senescence and NLRP3-related inflammation

Senescence represents a major risk factor promoting liver fibrosis progression. Sirtuin 1 (SIRT1), an essential regulator of cellular senescence, may be involved in developing liver fibrosis. However, the role and mechanism of SIRT1 in liver fibrosis development were largely unknown. We constructed the liver fibrosis in aged rats induced by carbon tetrachloride (CCl4) and then transfected with GFP-SIRT1 adenoviral vectors. After that, we performed acetylomic analysis of liver tissue in aged rats to identify potential substrates of SIRT1. Furthermore, replicative senescent rat hepatocytes were pretreated with siRNA HnRNP U, SIRT1 adenoviral vectors, resveratrol, and siRNA SIRT1, following stimulation with H2O2. We found that the protein levels of SIRT1 and HnRNP U were down-regulation in aged rat liver fibrotic tissues, with an accumulation of NLRP3 inflammasome and activation of the p53/p21 pathway in liver tissue, as well as an increased level of plasma IL-1β secretion. In comparison, these effects were reversed by overexpressing SIRT1 with adenoviral vectors. Acetylation of HnRNP U and its sites at K28 and K787 might be potential targets for SIRT1-mediated liver fibrosis in aged rats. Silencing HnRNP U reduced H2O2-induced up-regulation expression of p53, p21, and NLRP3 inflammasome at protein levels. Additionally, H2O2 induced high acetylation of HnRNP U in senescent hepatocytes, whereas overexpressing SIRT1 with adenoviral vectors and resveratrol deacetylate HnRNP U to inhibit NLRP3 inflammasome and the p53/p21 pathway. Besides, the silence of SIRT1 aggravated H2O2-induced p53-related senescence and NLRP3-related inflammation in senescent hepatocytes. Our findings suggested that deacetylation of HnRNPU mediated by SIRT1 attenuated liver fibrosis in the elderly by inhibiting p53/p21 pathway and NLRP3-related inflammation.

MicroRNA 29a alleviates mitochondrial stress in diet-induced NAFLD by inhibiting the MAVS pathway

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder characterized by fat accumulation in the liver. This leads to aggravated hepatocyte inflammation due to impaired mitochondrial function, mitochondrial double-stranded RNA (mt-dsRNA) release, elevated oxidative stress, and reactive oxygen species (ROS) production.MicroRNA-29a (miR-29a) is used to reduce hepatic fibrosis in cases of cholestatic liver damage and lessen the severity of non-alcoholic steatohepatitis in animal studies by influencing mitochondrial protein balance. However, the effectiveness of miR-29a in diminishing mt-dsRNA-induced exacerbation of NAFLD remains poorly understood, particularly in the context of a Western diet (WD). Our results have found that mice with increased miR-29a levels and fed a WD showed notably decreased serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol, and low-density lipoprotein cholesterol levels. They also experienced less weight gain and lower final body and liver weights. In addition, overexpression of miR-29a reduced the severity of fibrosis, alleviated hepatic oxidative stress, misfolded protein aggregates, and the release of mt-dsRNA. Moreover, miR-29a attenuated the innate immune mitochondrial antiviral-signaling protein (MAVS) pathway response. In vitro, the research using HepG2 cells confirmed that miR-29a reduces MAVS expression and decreases the release of mt-dsRNA and superoxide initiated by palmitic acid (PA). Analysis of luciferase activity further established that the specific binding of miR-29a to the 3′UTR of MAVS led to a repression of its expression. In conclusion, these groundbreaking findings underscore the potential of miR-29a in improving the treatment of NAFLD and liver steatofibrosis by inhibiting the MAVS signaling pathway.

Repurposing of the analgesic Neurotropin for MASLD/MASH treatment.

The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) has increased in recent decades. Approximately 25% of patients with MASLD progress to metabolic dysfunction-associated steatohepatitis, which is characterized by hepatic steatosis plus hepatocyte damage, inflammation, and fibrosis. We previously reported that Neurotropin (NTP), a drug used for relieving pain in Japan and China, inhibits lipid accumulation in hepatocytes by preventing mitochondrial dysfunction. We hypothesized that inhibiting hepatic steatosis and inflammation by NTP can be an effective strategy for treating MASLD and tested this hypothesis in a MASLD mouse model. Six-week-old C57BL/6NJ male mice were fed a normal diet and normal drinking water or a high-fat diet with high fructose/glucose water for 12 weeks. During the last 6 weeks, the mice were also given high-dose NTP, low-dose NTP, or control treatment. Histologic, biochemical, and functional tests were conducted. MitoPlex, a new proteomic platform, was used to measure mitochondrial proteins, as mitochondrial dysfunction was previously reported to be associated with MASLD progression. NTP inhibited the development of hepatic steatosis, injury, inflammation, and fibrosis induced by feeding a high-fat diet plus high fructose/glucose in drinking water. NTP also inhibited HSC activation. MitoPlex analysis revealed that NTP upregulated the expression of mitochondrial proteins related to oxidative phosphorylation, the tricarboxylic acid cycle, mitochondrial dynamics, and fatty acid transport. Our results indicate that NTP prevents the development of hepatic steatosis, injury, and inflammation by preserving mitochondrial function in the liver and inhibits liver fibrosis by suppressing HSC activation. Thus, repurposing NTP may be a beneficial option for treating MASLD/metabolic dysfunction-associated steatohepatitis.

Sub-chronic Hepatotoxicity Assessment of Ghana Cleanser® in Exposed Wistar Rats

This study evaluated the toxicity of a polyherbal Formulation (Ghana Cleanser®) on liver function markers of exposed albino rats. Thirty (30) male and female rats of the Wistar strain were randomly allotted into six (6) groups with n=5. 10.0 mL/kg distilled water was given to control groups 1 and 4. Polyherbal formulation doses of 374.0 mg/kg and 187.0 mg/kg were administered to groups 2-3 and 5-6, respectively. A modified Lorke's approach was used to compute acute toxicity. Animals were euthanized after 60 days under diethyl ether. Blood was collected for biochemical analyses through cardiac puncture. The liver was excised from each animal and was fixed in 10% buffered formaldehyde and prepared for histological assessment. LD50 of the polyherbal preparation was calculated as 3740 mg/kg (oral). The results indicated an appreciable increase (p<0.05) in ALT activity at 374.0 mg/kg in female rats; while there was no increase recorded at 187.0mg/kg in male rats. A significant increase in ALT activity was recorded at 374 mg/kg in male rats as well and increased AST activities were recorded at 187mg/kg in female rats. In the treated animals of both sexes, ALP activities were significantly elevated. Histopathology assessment of the hepatocytes showed no significant damage at 187 mg/kg in rats of both sexes when compared with their respective controls while some degrees of pathologies such as hepatocyte inflammation, hyperplasia, and congestion were recorded at 374 mg/kg in rats of both sexes. Results suggest caution on the long-term use of the polyherbal mixture due to its hepatotoxic potential.

CXCL9, IL2RB, and SPP1, potential diagnostic biomarkers in the co-morbidity pattern of atherosclerosis and non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is a hepatocyte inflammation based on hepatocellular steatosis, yet there is no effective drug treatment. Atherosclerosis (AS) is caused by lipid deposition in the endothelium, which can lead to various cardiovascular diseases. NASH and AS share common risk factors, and NASH can also elevate the risk of AS, causing a higher morbidity and mortality rate for atherosclerotic heart disease. Therefore, timely detection and diagnosis of NASH and AS are particularly important. In this study, differential gene expression analysis and weighted gene co-expression network analysis were performed on the AS (GSE100927) and NASH (GSE89632) datasets to obtain common crosstalk genes, respectively. Then, candidate Hub genes were screened using four topological algorithms and externally validated in the GSE43292 and GSE63067 datasets to obtain Hub genes. Furthermore, immune infiltration analysis and gene set variation analysis were performed on the Hub genes to explore the underlying mechanisms. The DGIbd database was used to screen candidate drugs for AS and NASH. Finally, a NASH model was constructed using free fatty acid-induced human L02 cells, an AS model was constructed using lipopolysaccharide-induced HUVECs, and a co-morbidity model was constructed using L02 cells and HUVECs to verify Hub gene expression. The result showed that a total of 113 genes common to both AS and NASH were identified as crosstalk genes, and enrichment analysis indicated that these genes were mainly involved in the regulation of immune and metabolism-related pathways. 28 candidate Hub genes were screened according to four topological algorithms, and CXCL9, IL2RB, and SPP1 were identified as Hub genes after in vitro experiments and external dataset validation. The ROC curves and SVM modeling demonstrated the good diagnostic efficacy of these three Hub genes. In addition, the Hub genes are strongly associated with immune cell infiltration, especially macrophages and γ–δ T cell infiltration. Finally, five potential therapeutic drugs were identified. has-miR-185 and hsa-miR-335 were closely related to AS and NASH. This study demonstrates that CXCL9, IL2RB, and SPP1 may serve as potential biomarkers for the diagnosis of the co-morbidity patterns of AS and NASH and as potential targets for drug therapy.

Mitochondria at the Crossroads of Cholestatic Liver Injury: Targeting Novel Therapeutic Avenues.

Bile acids are byproducts of cholesterol metabolism in the liver and constitute the primary components of bile. Disruption of bile flow leads to cholestasis, characterized by the accumulation of hydrophobic bile acids in the liver and bloodstream. Such accumulation can exacerbate liver impairment. This review discussed recent developments in understanding how bile acids contribute to liver damage, including disturbances in mitochondrial function, endoplasmic reticulum stress, inflammation, and autophagy dysfunction. Mitochondria play a pivotal role in cholestatic liver injury by influencing hepatocyte apoptosis and inflammation. Recent findings linking bile acids to liver damage highlight new potential treatment targets for cholestatic liver injury.

Treatment of NAFLD: Diet, Physical Activity, and Potential Pharmacological Options

Introduction and purpose Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the world, and according to current data, it affects 38% of the global population. NAFLD includes non-alcoholic fatty liver and the progressive form called non-alcoholic steatohepatitis, which is characterized by damage, inflammation of hepatocytes, and fibrosis. NASH can lead to cirrhosis and hepatocellular carcinoma. Moreover, it increases the risk of diabetes mellitus type 2, lipid disorders, and death due to cardiovascular causes. Currently, no cure is aimed at reducing the severity of NALFD and liver fibrosis. The aim of this study was to provide a total review of the current state of knowledge regarding NAFLD treatment and to identify potential areas for further evaluation. Materials and method The PubMed and Google Scholar databases were thoroughly searched to select appropriate sources for this article. A brief description of the state of knowledge Diet, weight management, and physical activity constitute fundamental elements of every treatment regimen for NAFLD. Regarding pharmacological treatment, European guidelines recommend the use of vitamin E or pioglitazone in certain patients. Recently, the topic of NAFLD treatment has been a popular subject among scientists who are striving to discover new therapeutic options. A lot of recent research has exhibited promising outcomes for GLP-1 agonists, metformin, SGLT2 inhibitors, FXR, and PPAR ligands. Summary The findings of the conducted studies so far are encouraging and offer promise for novel pharmacological interventions in the treatment of NAFLD. Nonetheless, before implementation, further research in this area will be imperative to comprehensively evaluate the efficacy and safety profiles of these pharmaceuticals.

Gut microbial metabolites in MASLD: Implications of mitochondrial dysfunction in the pathogenesis and treatment.

With an increasing prevalence, metabolic dysfunction-associated steatotic liver disease (MASLD) has become a major global health problem. MASLD is well-known as a multifactorial disease. Mitochondrial dysfunction and alterations in the gut bacteria are 2 vital events in MASLD. Recent studies have highlighted the cross-talk between microbiota and mitochondria, and mitochondria are recognized as pivotal targets of the gut microbiota to modulate the host's physiological state. Mitochondrial dysfunction plays a vital role in MASLD and is associated with multiple pathological changes, including hepatocyte steatosis, oxidative stress, inflammation, and fibrosis. Metabolites are crucial mediators of the gut microbiota that influence extraintestinal organs. Additionally, regulation of the composition of gut bacteria may serve as a promising therapeutic strategy for MASLD. This study reviewed the potential roles of several common metabolites in MASLD, emphasizing their impact on mitochondrial function. Finally, we discuss the current treatments for MASLD, including probiotics, prebiotics, antibiotics, and fecal microbiota transplantation. These methods concentrate on restoring the gut microbiota to promote host health.

Diosgenin attenuates nonalcoholic hepatic steatosis through the hepatic SIRT1/PGC-1α pathway

The prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing worldwide in recent years, causing severe economic and social burdens. Therefore, the lack of currently approved drugs for anti-NAFLD has gradually gained attention. SIRT1, as a member of the sirtuins family, is now the most widely studied in the pathophysiology of many metabolic diseases, and has great potential for preventing and treating NAFLD. Natural products such as Diosgenin (DG) have the potential to be developed as clinical drugs for the treatment of NAFLD due to their excellent multi-target therapeutic effects. In this study, we found that DG can activate the SIRT1/PGC-1α pathway and upregulate the expression of its downstream targets nuclear respiratory factor 1 (NRF1), complex IV (COX IV), mitofusin-2 (MFN2), and PPARα (perox-isome proliferator-activated receptor α) in SD rats induced by high-fat diet (HFD) and HepG2 cells caused by free fatty acids (FFAs, sodium oleate: sodium palmitate = 2:1). Conversely, the levels of dynamin-related protein 1 (DRP1) and inflammatory factors, including NF-κB p65, IL6, and TNFα, were downregulated both in vitro and in vivo. This improved mitochondrial dysfunction, fatty acid oxidation (FAO), lipid accumulation, steatosis, oxidative stress, and hepatocyte inflammation. Subsequently, we applied SIRT1 inhibitor EX527 and SIRT1 agonist SRT1720 to confirm further the necessity of activating SIRT1 for DG to exert therapeutic effects on NAFLD. In summary, these results further demonstrate the potential therapeutic role of DG as a SIRT1 natural agonist for NAFLD. (Graphical Abstracts)

Association of Circulating Markers of Microbial Translocation and Hepatic Inflammation with Liver Injury in Patients with Type 2 Diabetes.

Virtually the entire spectrum of liver disease is observed in association with type 2 diabetes mellitus (T2DM); indeed, T2DM is now the most common cause of liver disease in the U.S. We conducted a pilot study to investigate the relevance of increased microbial translocation and systemic inflammation in the development of liver injury in patients with T2DM. Patients with T2DM (n = 17) and non-diabetic controls (NDC; n = 11) aged 25-80 yrs. participated in this study. Serum levels of endotoxin, calprotectin, soluble CD14 and CD163, and several inflammatory cytokines were measured. In addition to standard liver injury markers, ALT and AST, novel serum markers of liver injury, keratin 18 (K-18) M30 (apoptosis-associated caspase-cleaved keratin 18), and M65 (soluble keratin 18) were evaluated. Statistical analyses were performed using the Mann-Whitney test to assess differences between study groups. Pearson's correlation analysis was performed to determine the strength of association between two variables using GraphPad Prism 9.5.0 software. Patients with T2DM had significantly higher levels of sCD14 in comparison to NDC, suggesting an increase in gut permeability, microbial translocation, and monocyte/macrophage activation. Importantly, relevant to the ensuing inflammatory responses, the increase in sCD14 in patients with T2DM was accompanied by a significant increase in sCD163, a marker of hepatic Kupffer cell activation and inflammation. Further, a positive correlation was observed between sCD163 and endotoxin and sCD14 in T2DM patients but not in NDC. In association with these changes, keratin 18 (K-18)-based serum markers (M65 and M30) that reflect hepatocyte death were significantly higher in the T2DM group indicating ongoing liver injury. Notably, both M65 and M30 levels correlated with sCD14 and sCD163, suggesting that immune cell activation and hepatic inflammation may be linked to the development of liver injury in T2DM. These findings suggest that the pathogenic changes in the gut-liver axis, marked by increased microbial translocation, may be a major component in the etiology of hepatocyte inflammation and injury in patients with T2DM. However, larger longitudinal studies, including histological evidence, are needed to confirm these observations.

The Influence of Emodin Succinyl Ethyl Ester on Non-alcoholic Steatohepatitis Induced by a Diet High in Fructose, Cholesterol, and Fat in Mice.

Nonalcoholic steatohepatitis (NASH) is a subtype of nonalcoholic fatty liver disease (NAFLD) characterized by hepatic steatosis and evidence of hepatocyte injury (ballooning) and inflammation, with or without liver fibrosis. In this study, after 12 weeks of induction, the mice were treated with emodin succinyl ethyl ester (ESEE) for four weeks at doses of 10/30/90 mg/kg/d. The blood analysis of experimental endpoints showed that ESEE exhibited significant therapeutic effects on the progression of disorders of glycolipid metabolism and the induced liver injury in the model animals. Histopathological diagnosis of the liver and total triglyceride measurements revealed that ESEE had a significant therapeutic effect on the histopathological features of nonalcoholic fatty liver disease/hepatitis, such as cellular steatosis and activation of intrahepatic inflammation. Additionally, ESEE was able to improve hepatocyte fat deposition, steatosis, and the course of intrahepatic inflammatory activity. Furthermore, it showed some inhibitory effect on liver fibrosis in the model animals. In summary, this study confirms the therapeutic effects of ESEE on the NAFLD/NASH model in C57BL/6J mice induced by a high-fat, high cholesterol, and fructose diet. These effects were observed through improvements in liver function, inhibition of fibrosis, and inflammatory responses. Changes in blood glucose levels, blood lipid metabolism, liver histopathological staining, liver fibrosis staining, and related pathological scores further supported the therapeutic effects of ESEE. Therefore, this study has important implications for the exploration of novel drugs for nonalcoholic fatty liver disease.