PI3K/AKT inhibitors aggravate death receptor-mediated hepatocyte apoptosis and liver injury

TJ0113-induced mitophagy in acute liver failure detected by Raman microspectroscopy

Impaired mitophagy underlies the pathophysiology of acute liver failure (ALF) and is closely associated with tissue damage and dysfunction. A novel mitophagy inducer, TJ0113, was used for treatment during ALF pathogenesis. In this study, we used a novel mitophagy inducer, TJ0113, to investigate the effects and mechanisms of TAA-induced ALF mice. The results showed that TJ0113 could enhance mitophagy through Parkin/PINK1 and ATG5 pathways, which in turn attenuated mitochondrial damage, hepatocyte apoptosis, nuclear factor (NF)-κB/NLRP3 signaling activation and inflammatory responses after TAA. Metabolomics results showed that TJ0113 mainly regulated lipid metabolism, amino acid metabolism and nucleotide metabolism in the livers of ALF mice. RNA sequencing (RNA-seq) analysis yielded that TJ0113 was involved in the development of ALF by regulating the P13K/AKT signaling pathway. The key highlight of this work is the use of an aberration-free line-scanning confocal Raman imager (AFLSCRI) to study the molecular changes in blood, liver tissue, gastrocnemius muscle, and mitochondrial extracts in ALF mice after TJ0113 treatment. Compared to the measurement with conventional assays, Raman microspectroscopy (micro-Raman) offers the benefits of being rapid, non-invasive, label-free and real-time. Our results found good agreement between Raman signals and histopathologic findings. The system has good performance with a spatial resolution of 2 μm, a spectral resolution of 4 cm-1 and a fast detection speed improved by 2 orders. Innovations in this test contribute to clinical diagnosis of disease, personalized treatment, effective intraoperative guidance and accurate prognosis. The data may help in the development of a non-invasive clinical device for mitochondrial damage using bedside micro-Raman.

FAS mediates apoptosis, inflammation, and treatment of pathogen infection

The FAS cell surface death receptor, a member of the tumor necrosis factor receptor family, activates both apoptotic and non-apoptotic signaling upon interaction with its ligand FASL. It is critical in cell migration, invasion, immune responses, and carcinogenesis. Pathogen infection can influence host cells' behavior by modulating the FAS/FASL pathway, thereby influencing disease progression. Understanding the role of FAS signaling in the context of pathogen interactions is therefore crucial. This review examines FAS-mediated apoptotic and non-apoptotic signaling pathways, with particular emphasis on the mechanisms of apoptosis and inflammation induced by bacterial and viral infections. Additionally, it highlights therapeutic strategies, including drug, cytokine, antibody, and FASL recombinant protein therapies, providing new directions for treating pathogenic infections and cancers, as well as insights into developing novel therapeutic approaches.

Indole-3-propionic acid promotes hepatic stellate cells inactivation

BACKGROUND & AIMS

We have previously reported that the serum levels of gut-derived tryptophan metabolite indole-3-propionic acid (IPA) are lower in individuals with liver fibrosis. Now, we explored the transcriptome and DNA methylome associated with serum IPA levels in human liver from obese individuals together with IPA effects on shifting the hepatic stellate cell (HSC) phenotype to inactivation in vitro.

METHODS

A total of 116 obese individuals without type 2 diabetes (T2D) (age 46.8 ± 9.3 years; BMI: 42.7 ± 5.0 kg/m2) from the Kuopio OBesity Surgery (KOBS) study undergoing bariatric surgery were included. Circulating IPA levels were measured using LC-MS, liver transcriptomics with total RNA-sequencing and DNA methylation with Infinium HumanMethylation450 BeadChip. Human hepatic stellate cells (LX-2) where used for in vitro experiments.

RESULTS

Serum IPA levels were associated with the expression of liver genes enriched for apoptosis, mitophagy and longevity pathways in the liver. AKT serine/threonine kinase 1 (AKT1) was the shared and topmost interactive gene from the liver transcript and DNA methylation profile. IPA treatment induced apoptosis, reduced mitochondrial respiration as well as modified cell morphology, and mitochondrial dynamics by modulating the expression of genes known to regulate fibrosis, apoptosis, and survival in LX-2 cells.

CONCLUSION

In conclusion, these data support that IPA has a plausible therapeutic effect and may induce apoptosis and the HSC phenotype towards the inactivation state, extending the possibilities to suppress hepatic fibrogenesis by interfering with HSC activation and mitochondrial metabolism.

Integrated multiomics approach and pathological analyses provide new insights into hepatic injury and metabolic alterations in Saanen goats after dietary exposure to aflatoxin B1

Exploring the toxicity and metabolic mechanisms of aflatoxin B1 (AFB1) in ruminants can help to develop strategies to prevent or reduce the transfer of the toxin and its metabolites to milk and meat. This study aimed to explore the effects of 3 concentrations of dietary AFB1 (0, 50, and 500 μg/kg) on hepatic injury and metabolism in Saanen goats via histological examination, western blot analysis, as well as integrated multiomics techniques. Eighteen Saanen goats were assigned to 1 of 3 treatments and the AFB1 challenge lasted for 14 d. Results showed that the liver tissue was enlarged and the relative organ index of the liver was linearly increased with elevated AFB1 levels. The hepatocyte apoptosis rate was significantly increased after AFB1 exposure, and the western blotting results revealed that both the external apoptotic pathway and mitochondrial-mediated intrinsic apoptotic pathway might be involved in AFB1-induced hepatocyte apoptosis. We identified 251, 269, and 154 significant differentially expressed genes (DEG) and 340, 596, and 127 significant differential metabolites in comparisons between the control (CON; 0 μg/kg) and low-dose (LO; 50 μg/kg) groups, the CON and high-dose (HI; 500 μg/kg) groups, and the LO and HI groups, respectively. The DEG annotated were mainly involved in the cell part, cell, single-organism process, cellular process, binding, and other functional categories. The identified metabolites primarily belonged to glycerophospholipids, prenol lipids, carboxylic acids, and derivatives. Integrative analysis of transcriptomics and metabolomics revealed that glycerophospholipids metabolism and choline metabolism in cancer were the most affected pathways related to AFB1 exposure. The identified differential metabolites, DEG, and pathways might have played a crucial role in the hepatic injury induced by AFB1 in goats.

Akkermansia muciniphila Mediated the Preventive Effect of Disulfiram on Acute Liver Injury via PI3K/Akt Pathway

Acetaminophen induced acute liver injury (ALI) has a high incidence and is a serious medical problem, but there is a lack of effective treatment. The enterohepatic axis is one of the targets of recent attention due to its important role in liver diseases. Disulfiram (DSF) is a multitarget drug that has been proven to play a role in a variety of liver diseases and can affect intestinal flora, but whether it can alleviate ALI is not clear. We utilised bacterial 16S rRNA gene profiling, antimicrobial treatments, and faecal microbiota transplantation tests to explore whether DSF therapy for ALI is dependent on gut microbiota. Our findings indicate that DSF primarily restores intestinal microbiome balance by modulating the abundance of Akkermansia muciniphila (A. muciniphila), leading to significant alleviation of ALI symptoms in a gut microbiota dependent manner. We also found that A. muciniphila can promote the activation of PI3K/Akt pathway, correct the Bcl-2/Bax ratio, and further inhibit hepatocyte apoptosis. In conclusion, DSF ameliorates ALI by modulating the intestinal microbiome and activating the PI3K/AKT pathway through A. muciniphila.

Dexpanthenol exhibits antiapoptotic and anti-inflammatory effects against nicotine-induced liver damage by modulating Bax/Bcl-xL, Caspase-3/9, and Akt/NF-κB pathways

Chronic tobacco use can lead to liver damage and inflammation due to the accumulation of various toxins in the body. This study aimed to investigate the correlation between the molecular mechanisms of nicotine-induced liver injury, the caspase cascade, and the Akt/NF-κB signaling pathway, as well as the protective effects of dexpanthenol (DEX). Male rats were subjected to intraperitoneal injections of nicotine at a concentration of 0.5 mg/kg/day and/or DEX at a concentration of 500 mg/kg/day for 8 weeks. After the treatment period, liver function tests were conducted on serum samples, and tissue samples were analyzed for protein levels of Akt, NF-κB, Bax, Bcl-xL, Caspase-3, and Caspase-9, along with histopathological changes. Additionally, assessments of oxidative stress markers and proinflammatory cytokines were carried out. Nicotine administration led to elevated levels of IL-6, IL-1β, MDA, TOS, and oxidative stress index, accompanied by decreased TAS levels. Moreover, nicotine exposure reduced the p-Akt/Akt ratio, increased NF-κB, Bax, Caspase-3, and Caspase-9 protein levels, and decreased the antiapoptotic protein Bcl-xL levels. DEX treatment significantly mitigated these effects, restoring the parameters to levels comparable to those of the control group. Nicotine-induced liver injury resulted in oxidative stress, inflammation, and apoptosis, mediated by Bax/Bcl-xL, Caspase-3, Caspase-9, and Akt/NF-κB pathways. Conversely, DEX effectively attenuated nicotine-induced liver injury by modulating apoptosis through NF-κB, Caspase-3, Caspase-9, Bax inhibition, and Bcl-xL activation.

A novel small molecule, CU05-1189, targeting the pleckstrin homology domain of PDK1 suppresses VEGF-mediated angiogenesis and tumor growth by blocking the Akt signaling pathway

Inhibition of angiogenesis is considered a promising therapeutic approach for cancer treatment. Our previous genetic research showed that the use of a cell-penetrating peptide to inhibit the pleckstrin homology (PH) domain of 3-phosphoinositide-dependent kinase 1 (PDK1) was a viable approach to suppress pathological angiogenesis. Herein, we synthesized and characterized a novel small molecule, CU05-1189, based on our prior study and present evidence for the first time that this compound possesses antiangiogenic properties both in vitro and in vivo. The computational analysis showed that CU05-1189 can interact with the PH domain of PDK1, and it significantly inhibited vascular endothelial growth factor (VEGF)-induced proliferation, migration, invasion, and tube formation in human umbilical vein endothelial cells without apparent toxicity. Western blot analysis revealed that the Akt signaling pathway was specifically inhibited by CU05-1189 upon VEGF stimulation, without affecting other VEGF receptor 2 downstream molecules or cytosolic substrates of PDK1, by preventing translocation of PDK1 to the plasma membrane. We also found that CU05-1189 suppressed VEGF-mediated vascular network formation in a Matrigel plug assay. More importantly, CU05-1189 had a good pharmacokinetic profile with a bioavailability of 68%. These results led to the oral administration of CU05-1189, which resulted in reduced tumor microvessel density and growth in a xenograft mouse model. Taken together, our data suggest that CU05-1189 may have great potential and be a promising lead as a novel antiangiogenic agent for cancer treatment.

The diagnostic or prognostic values of FADD in cancers based on pan‑cancer analysis

Previous studies have determined that aberrant expression of the fas-associated death domain (FADD) contributes to the development of cancer. However, no pan-cancer analysis has been reported to explore the relationship between FADD and various cancers. Multiple databases were screened to identify cancer datasets for the present study and to validate the expression of FADD in various tumors. The association of FADD alteration with cancer prognosis, clinical features and tumor immunity was also evaluated. Reverse transcription-quantitative PCR (RT-qPCR) was utilized to confirm the expression of FADD in breast, colon, liver and gastric cancer cells. Analysis of Gene Expression Omnibus database and The Cancer Genome Atlas database indicated that FADD was highly expressed in breast invasive carcinoma (BRCA), cervical squamous cell carcinoma and endocervical adenocarcinoma, cholangiocarcinoma, colon adenocarcinoma (COAD), esophageal carcinoma (ESCA), kidney renal clear cell carcinoma, kidney renal papillary cell carcinoma, liver hepatocellular carcinoma (LIHC), lung adenocarcinoma (LUAD) and prostate adenocarcinoma, whereas RT-qPCR results revealed that FADD was highly expressed in breast cancer and colon cancer. Further analyses demonstrated that FADD expression was significantly altered in ESCA, head and neck squamous cell carcinoma (HNSC), lung squamous cell carcinoma and BRCA. FADD expression was observed to be a risk factor of the overall survival in patients with HNSC, LIHC and LUAD as demonstrated by Kaplan-Meier and Cox regression analyses. The results of the present study demonstrated that FADD is highly expressed in numerous malignancies and can be utilized as a biomarker for the diagnosis of BRCA, COAD, LIHC and stomach adenocarcinoma. Moreover, FADD expression is a predictive risk factor for the development of HNSC, LIHC and LUAD and can potentially be used as a prognostic marker for these cancers.

Ube4A maintains metabolic homeostasis and facilitates insulin signaling in vivo

OBJECTIVE

Defining the regulators of cell metabolism and signaling is essential to design new therapeutic strategies in obesity and NAFLD/NASH. E3 ubiquitin ligases control diverse cellular functions by ubiquitination-mediated regulation of protein targets, and thus their functional aberration is associated with many diseases. The E3 ligase Ube4A has been implicated in human obesity, inflammation, and cancer. However, its in vivo function is unknown, and no animal models are available to study this novel protein.

METHODS

A whole-body Ube4A knockout (UKO) mouse model was generated, and various metabolic parameters were compared in chow- and high fat diet (HFD)-fed WT and UKO mice, and in their liver, adipose tissue, and serum. Lipidomics and RNA-Seq studies were performed in the liver samples of HFD-fed WT and UKO mice. Proteomic studies were conducted to identify Ube4A's targets in metabolism. Furthermore, a mechanism by which Ube4A regulates metabolism was identified.

RESULTS

Although the body weight and composition of young, chow-fed WT and UKO mice are similar, the knockouts exhibit mild hyperinsulinemia and insulin resistance. HFD feeding substantially augments obesity, hyperinsulinemia, and insulin resistance in both sexes of UKO mice. HFD-fed white and brown adipose tissue depots of UKO mice have increased insulin resistance and inflammation and reduced energy metabolism. Moreover, Ube4A deletion exacerbates hepatic steatosis, inflammation, and liver injury in HFD-fed mice with increased lipid uptake and lipogenesis in hepatocytes. Acute insulin treatment resulted in impaired activation of the insulin effector protein kinase Akt in liver and adipose tissue of chow-fed UKO mice. We identified the Akt activator protein APPL1 as a Ube4A interactor. The K63-linked ubiquitination (K63-Ub) of Akt and APPL1, known to facilitate insulin-induced Akt activation, is impaired in UKO mice. Furthermore, Ube4A K63-ubiquitinates Akt in vitro.

CONCLUSION

Ube4A is a novel regulator of obesity, insulin resistance, adipose tissue dysfunction and NAFLD, and preventing its downregulation may ameliorate these diseases.

Emerging roles of tyrosine kinases in hepatic inflammatory diseases and therapeutic opportunities

Inflammation has been convicted of causing and worsening many liver diseases like acute liver failure, fibrosis, cirrhosis, fatty liver and liver cancer. Pattern recognition receptors (PRRs) like TLRs 4 and 9 localized on resident or recruited immune cells are well known cellular detectors of pathogen and damage-associated molecular patterns (PAMPs/DAMPs). Stimulation of these receptors generates the sterile and non-sterile inflammatory responses in the liver. When these responses are repeated, there will be a sustained liver injury that may progress to fibrosis and its outcomes. Crosstalk between inflammatory/fibrogenic-dependent streams and certain tyrosine kinases (TKs) has recently evolved in the context of hepatic diseases. Because of TKs increasing importance, their role should be elucidated to highlight effective approaches to manage the diverse liver disorders. This review will give a brief overview of types and functions of some TKs like BTK, JAKs, Syk, PI3K, Src and c-Abl, as well as receptors for TAM, PDGF, EGF, VEGF and HGF. It will then move to discuss the roles of these TKs in the regulation of the proinflammatory, fibrogenic and tumorigenic responses in the liver. Lastly, the therapeutic opportunities for targeting TKs in hepatic inflammatory disorders will be addressed. Overall, this review sheds light on the diverse TKs that have substantial roles in hepatic disorders and potential therapeutics modulating their activity.

Ginseng polysaccharide reduces autoimmune hepatitis inflammatory response by inhibiting PI3K/AKT and TLRs/NF-κB signaling pathways

BACKGROUND

Ginseng polysaccharides (GP) have been found to exhibit significant immune regulatory effects, making them a promising candidate for treating immune-related diseases. However, their mechanism of action in immune liver injury is not yet clear. The innovation of this study lies in exploring the mechanism of action of ginseng polysaccharides (GP) in immune liver injury. While GP has been previously identified for its immune regulatory effects, this study aims to provide a clearer understanding of its therapeutic potential for immune-related liver diseases.

PURPOSE

The purpose of this study is to characterize low molecular weight gingeng polysaccharides (LGP), investigate their effect on ConA-induced autoimmune hepatitis (AIH), and identify their potential molecular mechanisms.

METHODS

LGP was extracted and purified using water-alcohol precipitation, DEAE-52 cellulose column, and Sephadex G200. And its structure was analyzed. It was then evaluated for anti-inflammatory and hepatoprotective effects in ConA-induced cells and mice, assessing cellular viability and inflammation with Cell Counting Kit-8 (CCK-8), Reverse Transcription-polymerase Chain Reaction (RT-PCR), and Western Blot, and hepatic injury, inflammation, and apoptosis with various biochemical and staining methods.

RESULTS

LGP is a polysaccharide composed of glucose (Glu), galactose (Gal), and arabinose (Ara), with a molar ratio of 12.9:1.6:1.0. LGP has a low crystallinity amorphous powder structure and is free from impurities. LGP enhances cell viability and reduces inflammatory factors in ConA-induced RAW264.7 cells and inhibits inflammation and hepatocyte apoptosis in ConA-induced mice. LGP inhibits Phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) and Toll-like receptors/Nuclear factor kappa B (TLRs/NF-κB) signaling pathways in vitro and in vivo to treat AIH.

CONCLUSIONS

LGP was successfully extracted and purified, exhibiting potential as a treatment for ConA-induced autoimmune hepatitis due to its ability to inhibit the PI3K/AKT and TLRs/NF-κB signaling pathways and protect liver cells from damage.

PI3K/AKT pathway promotes keloid fibroblasts proliferation by enhancing glycolysis under hypoxia

Our previous study demonstrated altered glucose metabolism and enhanced phosphorylation of the PI3K/AKT pathway in keloid fibroblasts (KFb) under hypoxic conditions. However, whether the PI3K/AKT pathway influences KFb cell function by regulating glucose metabolism under hypoxic conditions remains unclear. Here, we show that when PI3K/AKT pathway was inactivated with LY294002, the protein expression of glycolytic enzymes decreased, while the amount of mitochondria and mitochondrial membrane potential increased. The key parameters of extracellular acidification rate markedly diminished, and those of oxygen consumption rate significantly increased after inhibition of the PI3K/AKT pathway. When the PI3K/AKT pathway was suppressed, the levels of reactive oxygen species (ROS) and mitochondrial ROS (mitoROS) were significantly increased. Meanwhile, cell proliferation, migration and invasion were inhibited, and apoptosis was increased when the PI3K/AKT pathway was blocked. Additionally, cell proliferation was compromised when KFb were treated with both SC79 (an activator of the PI3K/AKT pathway) and 2-deoxy-d-glucose (an inhibitor of glycolysis), compared with the SC79 group. Moreover, a positive feedback mechanism was demonstrated between the PI3K/AKT pathway and hypoxia-inducible factor-1α (HIF-1α). Our data collectively demonstrated that the PI3K/AKT pathway promotes proliferation and inhibits apoptosis in KFb under hypoxia by regulating glycolysis, indicating that the PI3K/AKT signalling pathway could be a therapeutic target for keloids.

Cardiac Hepatopathy: New Perspectives on Old Problems through a Prism of Endogenous Metabolic Regulations by Hepatokines

Cardiac hepatopathy refers to acute or chronic liver damage caused by cardiac dysfunction in the absence of any other possible causative reasons of liver injury. There is a large number of evidence of the fact that cardiac hepatopathy is associated with poor clinical outcomes in patients with acute or actually decompensated heart failure (HF). However, the currently dominated pathophysiological background does not explain a role of metabolic regulative proteins secreted by hepatocytes in progression of HF, including adverse cardiac remodeling, kidney injury, skeletal muscle dysfunction, osteopenia, sarcopenia and cardiac cachexia. The aim of this narrative review was to accumulate knowledge of hepatokines (adropin; fetuin-A, selenoprotein P, fibroblast growth factor-21, and alpha-1-microglobulin) as adaptive regulators of metabolic homeostasis in patients with HF. It is suggested that hepatokines play a crucial, causative role in inter-organ interactions and mediate tissue protective effects counteracting oxidative stress, inflammation, mitochondrial dysfunction, apoptosis and necrosis. The discriminative potencies of hepatokines for HF and damage of target organs in patients with known HF is under on-going scientific discussion and requires more investigations in the future.

Combined Docetaxel/Pictilisib-Loaded mPEGylated Nanocarriers with Dual HER2 Targeting Antibodies for Synergistic Chemotherapy of Breast Cancer

Introduction

Approximately 15%~30% of breast cancers have gene amplification or overexpression of the human epidermal growth factor receptor 2 (HER2), resulting in the chemotherapy resistance, a more-aggressive phenotype and poor prognosis.

Methods

We propose a strategy of nanocarriers co-loaded with docetaxel (DTX) and pictilisib (PIC) at a synergistic ratio and non-covalently bound with dual anti-HER2 epitopes bispecific antibodies (BsAbs: anti-HER2-IV/methoxy-polyethylene glycol (mPEG) and anti-HER2-II/methoxy-PEG) for synergistic targeting to overcome the therapeutic dilemmas of the resistance for HER2-targetable chemodrugs. DTX/PIC-loaded nanocarriers (D/P_NCs) were prepared with single emulsion methods and characterized using dynamic light scattering analysis, and the drug content was assayed by high-performance liquid chromatographic method. The integrity and function of BsABs were evaluated using sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked immunosorbent assay (ELISA). The in vitro cell studies and in vivo breast tumor-bearing mice model were used to evaluate the anti-cancer effect and biosafety of formulations.

Results

D/P_NCs optimally prepared exhibited a spherical morphology with small particle sizes (~140 nm), high drug loading (~5.5%), and good colloidal stability. The synergistic tumor cytotoxicity of loading DTX and PIC at 2:1 ratio in D/P_NCs was discovered. The BsAbs are successfully decorated on mPEGylated DTX/PIC-loaded nanocarriers via anti-mPEG moiety. In vitro studies revealed that non-covalent decoration with dual BsAbs on D_P-NCs significantly and synergistically increased cellular uptake, while with loading DTX and PIC at a synergistic ratio of 2:1 in D/P_NCs further resulted in synergistic cytotoxicity. In vivo tumor inhibition studies showed the comparable results for synergistic antitumor efficacy while minimizing systemic toxicity of chemodrugs.

Conclusion

Non-covalent modification with dual distinct epitopes BsAbs on the nanocarriers loaded with dual chemodrugs at a synergistic ratio was expected to be a promising therapeutic platform to overcome the chemoresistance of various cancers and warrants further development for future therapy in the clinical.

The construction of preclinical evidence for the treatment of liver fibrosis with quercetin: A systematic review and meta-analysis

Quercetin (3,3',4',5,7-pentahydroxyflavone), a flavonoid, is widely found in fruits and vegetables and exerts broad-spectrum pharmacological effects in the liver. Many studies have explored the bioactivity of quercetin in the treatment of liver fibrosis. Hence, through a systematic review and biological mechanism evaluation, this study aimed to construct a body of preclinical evidence for the treatment of liver fibrosis using quercetin. The literature used in this study was mainly obtained from four databases, and the SYRCLE list (10 items) was used to evaluate the quality of the included literature. A meta-analysis of HA, LN, and other indicators was performed via STATA 15.0 software. Subgroup analyses based on animal species and model protocol were performed to further obtain detailed results. Moreover, the therapeutic mechanism of quercetin was summarized in a directed network form based on a comprehensive search of the literature. After screening, a total of 14 articles (comprising 15 studies) involving 254 animals were included. The results from the analysis showed that the corresponding liver function indexes, such as the levels of HA and LN, were significantly improved in the quercetin group compared with the model group, and liver function, such as the levels of AST and ALT, were also improved in the quercetin group. The species- and model-based subgroup analyses of AST and ALT revealed that quercetin exerts a significant effect. The therapeutic mechanism of quercetin was shown to be related to multiple pathways involving anti-inflammatory and antioxidant activities and lipid accumulation, including regulation of the TGF-β, α-SMA, ROS, and P-AMPK pathways. The results showed that quercetin exerts an obvious effect on liver fibrosis, and more prominent improvement effects on liver function and liver fibrosis indicators were obtained with a dose of 5-200 mg during a treatment course ranging from 4 to 8 weeks. Quercetin might be a promising therapeutic for liver fibrosis.

Activation of natural killer T cells contributes to Th1 bias in the murine liver after 14 d of ethinylestradiol exposure

BACKGROUND

As the main component of oral contraceptives (OCs), ethinylestradiol (EE) has been widely applied as a model drug to induce murine intrahepatic cholestasis. The clinical counterpart of EE-induced cholestasis includes women who are taking OCs, sex hormone replacement therapy, and susceptible pregnant women. Taking intrahepatic cholestasis of pregnancy (ICP) as an example, ICP consumes the medical system due to its high-risk fetal burden and the impotency of ursodeoxycholic acid in reducing adverse perinatal outcomes.

AIM

To explore the mechanisms and therapeutic strategies of EE-induced cholestasis based on the liver immune microenvironment.

METHODS

Male C57BL/6J mice or invariant natural killer T (iNKT) cell deficiency (Jα18-/- mice) were administered with EE (10 mg/kg, subcutaneous) for 14 d.

RESULTS

Both Th1 and Th2 cytokines produced by NKT cells increased in the liver skewing toward a Th1 bias. The expression of the chemokine/chemokine receptor Cxcr6/Cxcl16, toll-like receptors, Ras/Rad, and PI3K/Bad signaling was upregulated after EE administration. EE also influenced bile acid synthase Cyp7a1, Cyp8b1, and tight junctions ZO-1 and Occludin, which might be associated with EE-induced cholestasis. iNKT cell deficiency (Jα18-/- mice) robustly alleviated cholestatic liver damage and lowered the expression of the abovementioned signaling pathways.

CONCLUSION

Hepatic NKT cells play a pathogenic role in EE-induced intrahepatic cholestasis. Our research improves the understanding of intrahepatic cholestasis by revealing the hepatic immune microenvironment and also provides a potential clinical treatment by regulating iNKT cells.

6,8-(1,3-Diaminoguanidine) luteolin and its Cr complex show hypoglycemic activities and alter intestinal microbiota composition in type 2 diabetes mice

Flavonoid compounds such as luteolin exhibit hypolipidemic effects, and there are few reports on the hypoglycemic activity of luteolin derivatives. In this research, 6,8-(1,3-diaminoguanidine) luteolin (DAGL) and its Cr complex (DAGL·Cr) were obtained as a result of structural modifications to luteolin, and the hypoglycemic activities and the composition of intestinal microbiota in T2DM mice were investigated. This study found that DAGL and DAGL·Cr could significantly restore body weight, FBG, OGTT, AUC, and GSP in T2DM mice. Moreover, the pancreatic islet function index and the biochemical indicators of serum and the liver were also significantly improved. The histopathological results also showed that DAGL and DAGL·Cr had a stronger repair ability in the liver and the pancreas. It was also revealed that the potential hypoglycemic mechanism of DAGL and DAGL·Cr was involved in the simultaneous regulation of PI3K/AKT-1/GSK-3β/GLUT-4 and PI3K/AKT-1/mTOR/S6K1/IRS-1. Furthermore, DAGL and DAGL·Cr could also regulate the structure of the intestinal microbiota and increase the content of SCFA to relieve the symptoms of hyperglycemia in T2DM mice. This included a significant reduction in the ratio of Firmicutes and Bacteroidetes (F/B), and at the genus level, an increase in the relative abundance of Alistipe and Ruminiclostridium, and improvement in the content of SCFA in the feces of T2DM mice. In conclusion, in this study, DAGL and DAGL·Cr were found to improve hyperglycemia in T2DM mice by improving the pancreatic islet function index, regulating the biochemical indicators of serum and the liver, repairing damaged tissues, and regulating the PI3K/AKT-1 signaling pathway as well as reducing F/B, increasing the relative abundance of intestinal beneficial microbiota, and the content of SCFA in the feces. The hypoglycemic effect of DAGL·Cr on the body weight, serum IL-10, serum IL-6, and pancreatic islet function index was significantly better than that of DAGL.

Integrating Network Analysis and Metabolomics to Reveal Mechanism of Huaganjian Decoction in Treatment of Cholestatic Hepatic Injury

Huaganjian decoction (HGJD) was first recorded in the classic "Jing Yue Quan Shu" during the Ming dynasty, and it has been extensively applied in clinical practice to treat liver diseases for over 300 years in China. However, its bioactive constituents and relevant pharmacological mechanism are still unclear. In this study, a strategy integrating network analysis and metabolomics was applied to reveal mechanism of HGJD in treating cholestatic hepatic injury (CHI). Firstly, we observed the therapeutic effect of HGJD against CHI with an alpha-naphthylisothiocyanate (ANIT) induced CHI rat model. Then, we utilized UPLC-Q-Exactive MS/MS method to analyze the serum migrant compounds of HGJD in CHI rats. Based on these compounds, network analysis was conducted to screen for potential active components, and key signaling pathways interrelated to therapeutic effect of HGJD. Meanwhile, serum metabolomics was utilized to investigate the underlying metabolic mechanism of HGJD against CHI. Finally, the predicted key pathway was verified by western blot and biochemical analysis using rat liver tissue from in vivo efficacy experiment. Our results showed that HGJD significantly alleviated ANIT induced CHI. Totally, 31 compounds originated from HGJD have been identified in the serum sample. PI3K/Akt/Nrf2 signaling pathway related to GSH synthesis was demonstrated as one of the major pathways interrelated to therapeutic effect of HGJD against CHI. This research supplied a helpful strategy to determine the potential bioactive compounds and mechanism of traditional Chinese medicine.

HK2 is associated with the Warburg effect and proliferation in liver cancer: Targets for effective therapy with glycyrrhizin

Glycyrrhizin (GA) is the most essential active ingredient in licorice root, and has a wide range of biological and pharmacological activities. The present study aimed to conduct a detailed analysis of the effects of GA on liver cancer (LC) cell proliferation and the Warburg effect. Hexokinase‑2 (HK2) is a glycolytic enzyme that catalyzes the Warburg effect. To this end, the LC HepG2 cell line was transfected with small interfering RNA‑HK2 or pCDNA3.1‑HK2, followed by GA treatment. A Cell Counting Kit‑8 assay and EdU staining were employed to evaluate the proliferation rate of LC cells. The expression levels of HK2 and the phosphorylation level of AKT were measured by reverse transcription‑quantitative PCR and western blotting, respectively. Furthermore, the glucose uptake capacity and lactic acid content were assessed by kits, and the glycolysis level was evaluated by assessing the extracellular acidification rate (ECAR) and the oxygen consumption rate (OCR). A pronounced increase in the OCR, and decreases in the cell proliferation, glucose uptake capacity, lactic acid content, ECAR and HK2 expression were detected in LC cells subjected to GA treatment or HK2‑knockdown. Conversely, overexpression of HK2 reversed these trends, indicating that glycyrrhizin may inhibit LC cell proliferation and the Warburg effect through suppression of HK2. In addition, it was revealed that the PI3K/AKT signaling pathway was associated with LC cell proliferation and the Warburg effect; notably, treatment of LC cells with the AKT agonist SC79 induced elevation of the ECAR, cell proliferation, glucose uptake capacity, lactic acid content, phosphorylated‑AKT and HK2 expression, and suppressed the OCR. In conclusion, GA may inhibit the Warburg effect and cell proliferation in LC by suppressing HK2 through blockade of the PI3K/AKT signaling pathway.

Visualization of Apoptosis in Three-Dimensional Cell Aggregates Based on Molecular Beacon Imaging

The objective of this study is to visualize cell apoptosis in three-dimensional (3D) cell aggregates based on molecular beacons (MB). Two types of MB for messenger RNA were used: caspase-3 MB as a target for apoptosis and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) MB as a control of stable fluorescence in cells. To enhance the MB internalization into cells, caspase-3 and GAPDH MB were incorporated in cationized gelatin nanospheres (cGNS), respectively (cGNS_{casp3 MB} and cGNS_{GAP MB}). In addition, cGNS co-incorporating caspase-3 and GAPDH MB (cGNS_{dual MB}) were prepared to perform the dual-color imaging for the same cell aggregate. The cGNS_MB were incubated with mouse mesenchymal stem cells to label with MB in the two-dimensional culture. The cell apoptosis mediated by the addition of antibody for a death receptor Fas was ratiometrically detected by the cGNS_{dual MB} to the same extent as single MB. The cell aggregates were prepared from MB-labeled cells, and the MB fluorescence was detected from almost all the cells even in the 3D aggregates to show the homogenous distribution. In addition to the Fas-mediated apoptosis, the aggregates were treated with camptothecin of a low-molecular weight apoptosis inducer. The fluorescence of caspase-3 MB was mainly distributed at the surface surrounding site of Fas-mediated apoptotic aggregates rather than the center site, while that of GAPDH MB was detected even in the interior site. On the other hand, in the camptothecin-induced apoptotic aggregates, both caspae-3 and GAPDH MB fluorescence were detected from the interior site of aggregates as well as the surrounding site. It is likely that the MB fluorescence reflected the localization of apoptotic position caused by the different molecular sizes of apoptosis inducer and the consequent penetration into the aggregates. It is concluded that the cGMS_MB are a promising system to visualize cell apoptosis in 3D cell aggregates without the destruction of aggregates.

Scutellarin Inhibits the Growth and EMT of Gastric Cancer Cells through Regulating PTEN/PI3K Pathway

Gastric cancer is one of the most common malignancies with a high mortality rate world. This study intends to make clear the role and mechanism of the Scutellarin (Scu), a flavonoid isolated from Erigeron breviscapus (Vant.) Hand.-Mazz, in regulating the evolvement of gastric cancer. We selected different doses of Scu to treat gastric cancer cells (MGC-803 and AGS). Then, cell counting kit-8 (CCK8) assay was conducted to verify the proliferation of tumor cells, while flow cytometry was adopted to test the apoptosis rate. Meanwhile, Western blot was conducted to examine epithelial-mesenchymal transition (EMT) markers and the expression of phosphatase and tensin homolog (PTEN)/phosphatidylinositol 3-kinase (PI3K) and apoptosis-related proteins (Bax, Bcl2 and Caspase3). Moreover, xenograft tumor experiment in nude mice was established to verify the effect of Scu on tumor growth. Furthermore, the knockdown model of PTEN was constructed, and the influence of PTEN on the anti-tumor effect of Scu was investigated. As a result, Scu inhibited cell proliferation, EMT and promoted the apoptosis in gastric cancer dose-dependently. Additionally, Scu attenuated tumor cell growth in vivo. Besides, Scu enhanced the expression of PTEN while reduced the phosphorylated level of PI3K. Moreover, the mechanistic study proved that Scu inactivated PI3K by up-regulating PTEN, thus dampening tumor progression. In conclusion, Scu dampened the growth and EMT of gastric cancer by regulating the PTEN/PI3K pathway.

REV-ERBα Agonist GSK4112 attenuates Fas-induced Acute Hepatic Damage in Mice

Fas-induced apoptosis is a central mechanism of hepatocyte damage during acute and chronic hepatic disorders. Increasing evidence suggests that circadian clock plays critical roles in the regulation of cell fates. In the present study, the potential significance of REV-ERBα, a core ingredient of circadian clock, in Fas-induced acute liver injury has been investigated. The anti-Fas antibody Jo2 was injected intraperitoneally in mice to induce acute liver injury and the REV-ERBα agonist GSK4112 was administered. The results indicated that treatment of GSK4112 decreased the level of plasma ALT and AST, attenuated the liver histological changes, and promoted the survival rate in Jo2-insulted mice. Treatment with GSK4112 also downregulated the activities of caspase-3 and caspase-8, suppressed hepatocyte apoptosis. In addition, treatment with GSK4112 decreased the level of Fas and enhanced the phosphorylation of Akt. In conclusion, treatment with GSK4112 alleviated Fas-induced apoptotic liver damage in mice, suggesting that REV-ERBα agonist might have potential value in pharmacological intervention of Fas-associated liver injury.

Kaempferol Inhibits Zearalenone-Induced Oxidative Stress and Apoptosis via the PI3K/Akt-Mediated Nrf2 Signaling Pathway: In Vitro and In Vivo Studies

In this study, kaempferol (KFL) shows hepatoprotective activity against zearalenone (ZEA)-induced oxidative stress and its underlying mechanisms in in vitro and in vivo models were investigated. Oxidative stress plays a critical role in the pathophysiology of various hepatic ailments and is normally regulated by reactive oxygen species (ROS). ZEA is a mycotoxin known to exert toxicity via inflammation and ROS accumulation. This study aims to explore the protective role of KFL against ZEA-triggered hepatic injury via the PI3K/Akt-regulated Nrf2 pathway. KFL augmented the phosphorylation of PI3K and Akt, which may stimulate antioxidative and antiapoptotic signaling in hepatic cells. KFL upregulated Nrf2 phosphorylation and the expression of antioxidant genes HO-1 and NQO-1 in a dose-dependent manner under ZEA-induced oxidative stress. Nrf2 knockdown via small-interfering RNA (siRNA) inhibited the KFL-mediated defence against ZEA-induced hepatotoxicity. In vivo studies showed that KFL decreased inflammation and lipid peroxidation and increased H₂O₂ scavenging and biochemical marker enzyme expression. KFL was able to normalize the expression of liver antioxidant enzymes SOD, CAT and GSH and showed a protective effect against ZEA-induced pathophysiology in the livers of mice. These outcomes demonstrate that KFL possesses notable hepatoprotective roles against ZEA-induced damage in vivo and in vitro. These protective properties of KFL may occur through the stimulation of Nrf2/HO-1 cascades and PI3K/Akt signaling.

Study on the protective effect and mechanism of Dicliptera chinensis (L.) Juss (Acanthaceae) polysaccharide on immune liver injury induced by LPS

The purpose of this study is to use Dicliptera chinensis (L.) Juss (Acanthaceae) polysaccharide (DCP) to act on the NF-κB inflammatory pathway and Fas/FasL ligand system, in order to find a new method to improve immune liver injury. Lipopolysaccharide (LPS) was used to establish an injury model in vivo (Kunming mice) and in vitro (LO2 cells). In this experiment, hematoxylin-eosin (H&E) staining and related biochemical indicators were used to observe the pathological changes of liver tissues, oxidative stress and inflammatory reactions. Immunohistochemistry, ELISA, RT-PCR and Western blot were used to detect protein or mRNA expressions associated with inflammation response and apoptosis. The experimental results show that the model group has obvious liver cell damage and inflammatory infiltration. After DCP intervention, it could significantly reduce the levels of ALT, AST, ALP, TBIL and MDA in serum, and increase the content of SOD and GSH-Px. In addition, DCP can reduce the expression level of NF-κB in the liver and reduce the release of downstream inflammatory factors TNF-α, IL-6 and IL-1β, thereby reducing the inflammation. At the same time, DCP can significantly inhibit the expression of Fas/FasL ligand system and apoptosis related-proteins and mRNA, which in turn can reduce cell apoptosis. In conclusion, DCP can alleviate liver injury by inhibiting liver inflammation and apoptosis, which provides a new strategy for clinical treatment of immune liver injury.

Cadmium-induced oxidative stress promotes apoptosis and necrosis through the regulation of the miR-216a-PI3K/AKT axis in common carp lymphocytes and antagonized by selenium

Cadmium (Cd) is a primary environmental pollutant which causes the immune dysfunction of aquatic animals. MicroRNAs (miRNAs) play a key role in programmed necrosis and apoptosis of immune organs. Selenium (Se), known as an important element, can antagonize Cd toxicity in birds, but the impact of Se on common carps (Cyprinus carpio) has not been reported. To investigate the Cd-induced immunotoxicity mechanism mediated by miR-216a in splenic lymphocytes of common carp and antagonized by Se, we extracted lymphocytes from the spleen and divided them into control group, Se group (10^-6 mol/L of Na₂SeO₃), Se + Cd group and Cd group (4 × 10^-5 mol/L of CdCl₂). After 6 h of incubation, AO/EB staining, Flow cytometry, qPCR and Western blot were performed. The results showed that Cd exposure caused the apoptosis (BAX, Bcl-2, Caspase 3, Caspase 9) and programmed necrosis (RIP, RIP3, MLKL) in lymphocytes, increased the expression of CYP enzymes, glycometabolism-related enzymes and production of ROS, while irritated the oxidative stress (MDA, SOD, CAT and GSH-PX), upregulated the expression of miR-216a which attenuated the levels of PI3K. However, those variations were apparently mitigated in the Se + Cd group. In short, we have proven that Cd activates oxidative stress and miR-216a-PI3K/AKT axis disorder, thus promoting apoptosis and necrosis in lymphocytes. Moreover, Se can antagonize Cd-triggered apoptosis and necrosis in lymphocytes.

Taxifolin ameliorates iron overload-induced hepatocellular injury: Modulating PI3K/AKT and p38 MAPK signaling, inflammatory response, and hepatocellular regeneration

Although physiological levels of iron are essential for numerous biological processes, excess iron causes critical tissue injury. Under iron overload conditions, non-chelated iron generates reactive oxygen species that mediate iron-induced tissue injury with subsequent induction of apoptosis, necrosis, and inflammatory responses. Because liver is a central player in iron metabolism and storage, it is vulnerable to iron-induced tissue injury. Taxifolin is naturally occurring compound that has shown potent antioxidant and potential iron chelation competency. The aim of the current study was to investigate the potential protective effects of taxifolin against iron-induced hepatocellular injury and to elucidate the underlining mechanisms using rats as a mammalian model. The results of the current work indicated that taxifolin inhibited iron-induced apoptosis and enhanced hepatocellular survival as demonstrated by decreased activity of caspase-3 and activation of the pro-survival signaling PI3K/AKT, respectively. Western blotting analysis revealed that taxifolin enhanced liver regeneration as indicated by increased PCNA protein abundance. Taxifolin mitigated the iron-induced histopathological aberration and reduced serum activity of liver enzymes (ALT and AST), highlighting enhanced liver cell integrity. Mechanistically, taxifolin modulated the redox-sensitive MAPK signaling (p38/c-Fos) and improved redox status of the liver tissues as indicated by decreased lipid peroxidation and protein oxidation along with enhanced total antioxidant capacity. Interestingly, it decreased liver iron content and down-regulated the pro-inflammatory cytokines TNF-α, IL-6, and IL-1β. Collectively, these data highlight, for the first time, the ameliorating effects of taxifolin against iron overload-induced hepatocellular injury that is potentially mediated through anti-inflammatory, antioxidant, and potential iron chelation activities.

Exogenous Therapeutics of Microrna-29a Attenuates Development of Hepatic Fibrosis in Cholestatic Animal Model through Regulation of Phosphoinositide 3-Kinase p85 Alpha

Recent studies have found that microRNA-29a (miR-29a) levels are significantly lower in fibrotic livers, as shown with human liver cirrhosis. Such downregulation influences the activation of hepatic stellate cells (HSC). Phosphoinositide 3-kinase p85 alpha (PI3KP85α) is implicated in the regulation of proteostasis mitochondrial integrity and unfolded protein response (UPR) and apoptosis in hepatocytes. This study aimed to investigate the potential therapeutic role of miR-29a in a murine bile duct ligation (BDL)-cholestatic injury and liver fibrosis model. Mice were assigned to four groups: sham, BDL, BDL + scramble miRs, and BDL + miR-29a-mimic. Liver fibrosis and inflammation were assessed by histological staining and mRNA/protein expression of representative markers. Exogenous therapeutics of miR-29a in BDL-stressed mice significantly attenuated glutamic oxaloacetic transaminase (GOT)/glutamic-pyruvic transaminase (GPT) and liver fibrosis, and caused a significant downregulation in markers related to inflammation (IL-1β), fibrogenesis (TGF-β1, α-SMA, and COL1α1), autophagy (p62 and LC3B II), mitochondrial unfolded protein response (UPR^mt; C/EBP homologous protein (CHOP), heat shock protein 60 (HSP60), and Lon protease-1 (LONP1, a mitochondrial protease), and PI3KP85α within the liver tissue. An in vitro luciferase reporter assay further confirmed that miR-29a mimic directly targets mRNA 3′ untranslated region (UTR) of PI3KP85α to suppress its expression in HepG2 cell line. Our data provide new insights that therapeutic miR-29a improves cholestasis-induced hepatic inflammation and fibrosis and proteotstasis via blocking PI3KP85α, highlighting the potential of miR-29a targeted therapy for liver injury.