No causal association between serum vitamin D levels and diabetes retinopathy: A Mendelian randomization analysis.

BACKGROUND AND AIM: Diabetes retinopathy (DR) is a common microvascular complication of diabetes, and it is the main cause of global vision loss. The current observational research results show that the causal relationship between Vitamin D and DR is still controversial. Therefore, we conducted a Mendelian randomization study to determine the potential causal relationship between serum 25-hydroxyvitamin D 25(OH)D and DR. METHODS AND RESULTS: In this study, we selected aggregated data on serum 25(OH)D levels (GWAS ID: ebi-a-GCST90000615) and DR (GWAS ID: finn-b-DM_RETINOPATHY) from a large-scale GWAS database. Then use MR analysis to evaluate the possible causal relationship between them. We mainly use inverse variance weighted (IVW), supplemented by MR Egger and weighted median methods. Sensitivity analysis is also used to ensure the stability of the results, such as Cochran's Q-test, MR-PRESSO, MR-Egger interception test, and retention method. The MR analysis results showed that there was no significant causal relationship between 25(OH)D and DR (OR = 1.0128, 95%CI=(0.9593,1.0693), P = 0.6447); Similarly, there was no significant causal relationship between DR and serum 25 (OH) D levels (OR = 0.9900, 95% CI=(0.9758,1.0045), P = 0.1771). CONCLUSION: Our study found no significant causal relationship between serum 25(OH)D levels and DR, and vice versa. A larger sample size randomized controlled trial is needed to further reveal its potential causal relationship.

EGR1 is crucial for the chlorogenic acid-provided promotion on liver regeneration and repair after APAP-induced liver injury.

Improper use of acetaminophen (APAP) will induce acute liver failure. This study is designed to investigate whether early growth response-1 (EGR1) participated in the promotion on liver repair and regeneration after APAP-induced hepatotoxicity provided by natural compound chlorogenic acid (CGA). APAP induced the nuclear accumulation of EGR1 in hepatocytes regulated by extracellular-regulated protein kinase (ERK)1/2. In Egr1 knockout (KO) mice, the liver damage caused by APAP (300 mg/kg) was more severe than in wild-type (WT) mice. Results of chromatin immunoprecipitation and sequencing (ChIP-Seq) manifested that EGR1 could bind to the promoter region in Becn1, Ccnd1, and Sqstm1 (p62) or the catalytic/modify subunit of glutamate-cysteine ligase (Gclc/Gclm). Autophagy formation and APAP-cysteine adduct (APAP-CYS) clearance were decreased in Egr1 KO mice administered with APAP. The EGR1 deletion reduced hepatic cyclin D1 expression at 6, 12, or 18 h post APAP administration. Meanwhile, the EGR1 deletion also decreased hepatic p62, Gclc and Gclm expression, GCL enzymatic activity, and glutathione (GSH) content and decreased nuclear factor erythroid 2-related factor 2 (Nrf2) activation and thus aggravated oxidative liver injury induced by APAP. CGA increased EGR1 nuclear accumulation; enhanced hepatic Ccnd1, p62, Gclc, and Gclm expression; and accelerated the liver regeneration and repair in APAP-intoxicated mice. In conclusion, EGR1 deficiency aggravated liver injury and obviously delayed liver regeneration post APAP-induced hepatotoxicity through inhibiting autophagy, enhancing liver oxidative injury, and retarding cell cycle progression, but CGA promoted the liver regeneration and repair in APAP-intoxicated mice via inducing EGR1 transcriptional activation.

[Discovery of miRNA and target signal molecules involved in inhibition of chlorogenic acid on N-acetyl-p-aminophenol-induced hepatotoxicity based on microRNA array].

This study aims to observe the effect of chlorogenic acid(CGA) on microRNA(miRNA) in the process of protecting against N-acetyl-p-aminophenol(APAP)-induced liver injury. Eighteen C57BL/6 mice were randomly assigned into a normal group, a model group(APAP, 300 mg·kg~(-1)), and a CGA(40 mg·kg~(-1)) group. Hepatotoxicity of mice was induced by intragastric administration of APAP(300 mg·kg~(-1)). The mice in the CGA group were administrated with CGA(40 mg·kg~(-1)) by gavage 1 h after APAP administration. The mice were sacrificed 6 h after APAP administration, and plasma and liver tissue samples were collected for the determination of serum alanine/aspartate aminotransferase(ALT/AST) level and observation of liver histopathology, respectively. MiRNA array combined with real-time PCR was employed to discover important miRNAs. The target genes of miRNAs were predicted via miRWalk and TargetScan 7.2, verified by real-time PCR, and then subjected to functional annotation and signaling pathway enrichment. The results showed that CGA administration lowered the serum ALT/AST level elevated by APAP and alleviate the liver injury. Nine potential miRNAs were screened out from the microarray. The expression of miR-2137 and miR-451a in the liver tissue was verified by real-time PCR. The expression of miR-2137 and miR-451a was significantly up-regulated after APAP administration, and such up-regulated expression was significantly down-regulated after CGA administration, consistent with the array results. The target genes of miR-2137 and miR-451a were predicted and verified. Eleven target genes were involved in the process of CGA protecting against APAP-induced liver injury. Gene Ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment with DAVID and R language showed that the 11 target genes were enriched in Rho protein-related signal transduction, vascular patterning-related biological processes, binding to transcription factors, and Rho guanyl-nucleotide exchange factor activity. The results indicated that miR-2137 and miR-451a played an important role in the inhibition of CGA on APAP-induced hepatotoxicity.

Diosbulbin B induced G2/M cell cycle arrest in hepatocytes by miRNA-186-3p and miRNA-378a-5p-mediated the decreased expression of CDK1.

Diosbulbin B (DB) is the main hepatotoxic compound in Airpotato yam, which is traditionally used for treating thyroid disease and cancer in China, and its hepatotoxic mechanism still remains unclear. This study aims to investigate its hepatotoxic mechanism by focusing on regulating microRNA (miRNA). DB induced hepatotoxicity both in vivo and in vitro. Results of miRNA chip analysis showed that the expression of eleven miRNAs was up-regulated and twelve miRNAs was down-regulated in livers from DB-treated mice. The altered expression of seven miRNAs was further validated by using real-time polymerase chain reaction (RT-PCR) assay. DB induced G2/M arrest in L-02/cytochrome P450 3A4 (CYP3A4) cells in both concentration- and time-dependent manner. A total of eleven predicted target genes was related with cell cycle regulation of those above seven miRNAs, among which the mRNA and protein expression of cyclin-dependent kinase 1 (CDK1) decreased both in vivo and in vitro. Both miR-378a-5p and miR-186-3p have binding sites in the 3'-untranslated region (UTR) of CDK1. With the use of CDK1 3'-UTR luciferase reporter assay, miR-378a-5p and miR-186-3p was found to down-regulate the luciferase activity. The mimics of miR-378a-5p or miR-186-3p reduced CDK1 expression in L-02/CYP3A4 cells, but their inhibitors reversed the decreased CDK1 expression induced by DB. Moreover, overexpression of miR-186-3p inhibitor reversed the G2/M cell cycle arrest induced by DB in L-02/CYP3A4 cells. Taken together, our results showed that DB induced hepatotoxicity by inducing G2/M cell cycle arrest in hepatocytes via miR-186-3p or miR-378a-5p-mediated the reduced CDK1 expression.

Exploring the efficacy and mechanism of Glycyrrhizae Radix et Rhizoma in improving collagen-induced arthritis in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Rheumatoid arthritis (RA), a chronic auto-immune disease, will cause serious joint damage and disability. Glycyrrhizae Radix et Rhizoma (GRR) is commonly included in many anti-RA formulas used in the clinical practice in China. AIM OF THE STUDY: To elucidate the alleviation of GRR and its active compounds on RA and the possible engaged mechanism. MATERIALS AND METHODS: The clinical score, paw swelling degree and pain threshold were detected in the collagen-induced arthritis (CIA) in DBA/1 mice. The ankle joints of mice were observed by using X-Ray, hematoxylin-eosin (H&E), masson's trichrome (Masson), and safranin O and fast green (Safranin O) staining. The potential targets of GRR were predicted by network pharmacology and further verified by using enzyme-linked immunosorbent assay (ELISA) and western-blot. Real-time polymerase chain reaction (Real-time PCR) and wound healing assay were conducted in synovial MH7A cells. The interaction between active compounds and potential targets predicted by molecular docking was confirmed by using cellular thermal shift assay (CETSA). RESULTS: GRR (615 mg/kg) obviously alleviated CIA in mice. Network pharmacology implied that GRR might affect angiogenesis and inflammation, among which vascular endothelial growth factor-A (VEGF-A), tumor necrosis factor-α (TNFα), interleukin-1ß (IL-1ß), IL-6 and phosphorylated protein kinase B (AKT) might be the key targets involved in this process. GRR decreased AKT phosphorylation and reduced the elevated levels of TNFα, VEGF-A, IL-1ß and IL-6. Next, in vitro results demonstrated that glycyrrhetinic acid (GA) and isoliquiritigenin (ISL) were two active compounds that inhibited TNFα-induced synovial cell angiogenesis and inflammation. Moreover, GA and ISL actually improved RA in CIA mice. The results of molecular docking and CETSA displayed that ISL and GA might interact with TNF receptor-1 (TNFR1), toll-like receptor-4 (TLR4) and VEGF receptor-2 (VEGFR2), thereby contributing to their inhibition on angiogenesis and inflammation. CONCLUSION: GRR and two active compounds, including ISL and GA, alleviated RA via inhibiting angiogenesis and inflammation.

2,3,5,4'-tetrahydroxy-stilbene-2-O-ß-D-glucoside promotes liver regeneration after partial hepatectomy in mice: the potential involvement of PPARα-mediated fatty acid metabolism.

ETHNOPHARMACOLOGICAL RELEVANCE: 2,3,5,4'-tetrahydroxy-stilbene-2-O-ß-D-glucoside (TSG) is the principal bioactive compound contained in Polygonum multiflorum Thunb. (PMT), which is traditionally recorded to possess tonic and anti-aging efficacy. AIM OF THE STUDY: To identify the TSG-provided promotion on liver regeneration (LR) following partial hepatectomy (PHx) in mice and to explicate its involved mechanism. MATERIALS AND METHODS: The promotion of TSG on LR was evaluated by hematoxylin and eosin (H&E), 5-bromodeoxyuridinc (BrdU) and Ki-67 staining, and measuring the level of proliferating cell nuclear antigen (PCNA) and Cyclin D1 in mice with PHx at different time points. Gene Expression Omnibus (GEO, GSE15239) database and the label-free quantitative proteomics from liver of mice at 24 h after PHx were integrated to identify potential involved critical proteins, which were verified by Western-blot, Real-time polymerase chain reaction (RT-PCR), molecular docking and luciferase activity assay. Primary hepatocytes isolated from mice were used to investigate the TSG-provided promotion on proliferation in vitro. RESULTS: TSG (20 mg/kg) promoted LR in mice after PHx. Results from RNA expression data from clinical samples and proteomic analysis from liver tissues indicated that peroxisome proliferator-activated receptor α (PPARα)-mediated fatty acid metabolism pathway were crucially associated with the TSG-provided promotion on LR. TSG enhanced the nuclear translocation of PPARα and the mRNA expression of a series of PPARα-regulated downstream genes. In addition, TSG lowered hepatic triglyceride (TG) and non-esterified fatty acid (NEFA) amounts and increased hepatic adenosine triphosphate (ATP) level in mice after PHx. TSG up-regulated the transcriptional activity of PPARα in vitro. Next results displayed that TSG promoted cell proliferation as well as ATP level in mice primary hepatocytes, which were abolished when PPARα was suppressed. Meanwhile, the cell viability was also elevated in mice primary hepatocytes treated with ATP. CONCLUSION: Activating PPARα-mediated fatty acid ß-oxidation (FAO) pathway led to the production of ATP, which contributed to the TSG-provided promotion on LR after PHx in mice.

Forsythiaside-A improved bile-duct-ligation-induced liver fibrosis in mice: The involvement of alleviating mitochondrial damage and ferroptosis in hepatocytes via activating Nrf2.

Liver fibrosis is a key and reversible stage in the progression of many chronic liver diseases to cirrhosis or hepatocellular carcinoma. Forsythiaside-A (FTA), a main compound isolated from Forsythiae Fructus, has an excellent liver protective activity. This study aims to investigate the efficacy of FTA in improving cholestatic liver fibrosis. Bile-duct-ligation (BDL) was conducted to induce liver fibrosis in mice. Hepatic collagen deposition was evaluated by Masson and Sirus red staining. The bile acid spectrum in the liver and serum was analyzed by mass spectrometry. Liver oxidative stress injury and mitochondria damage were observed by using Mito-Tracker Red fluorescence staining, transmission electron microscopy, etc. The level of ferrous iron (Fe2+) and the expression of ferroptosis-associated molecules were detected. The binding between FTA and its target protein was confirmed by Co-immunoprecipitation (Co-IP), cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) and surface plasmon resonance (SPR). Our results demonstrated that FTA alleviated BDL-induced liver fibrosis in mice. FTA did not decrease the elevated amount of bile acids in BDL-treated mice, but reduced the bile acid-induced mitochondrial damage, oxidative stress and ferroptosis in hepatocytes, and also induced nuclear factor erythroid 2-related factor-2 (Nrf2) activation. In Nrf2 knock-out mice, the FTA-provided protection against BDL-induced liver fibrosis was disappeared, and FTA's inhibition on mitochondrial damage, oxidative stress and ferroptosis were lowered. Further results displayed that FTA could directly bind to Kelch-like ECH-associated protein-1 (Keap1), thereby activating Nrf2. Moreover, the BDL-induced liver fibrosis was markedly weakened in liver-specific Keap1 knockout mice. Hence, this study suggests that FTA alleviated the BDL-induced liver fibrosis through attenuating mitochondrial damage and ferroptosis in hepatocytes by activating Nrf2 via directly binding to Keap1.

Identifying potential ferroptosis key genes for diagnosis and treatment of postmenopausal osteoporosis through competitive endogenous RNA network analysis.

Objective: Postmenopausal osteoporosis (PMOP) is a common systemic metabolic bone disorder that is owing to the reduced estrogen secretion and imbalance of bone absorption and bone formation in postmenopausal women. Ferroptosis has been identified as a novel modulatory mechanism of osteoporosis. Nevertheless, the particular modulatory mechanism between ferroptosis and PMOP is still unclear. The objective of the current investigation was to detect potential biomarkers connected to ferroptosis in PMOP and discover its probable mechanism through bioinformatics. Methods: We downloaded PMOP-related microarray datasets from the database of Gene Expression Omnibus (GEO) and obtained the differentially expressed genes (DEGs). Utilizing bioinformatics analysis, the DEGs were intersected with the ferroptosis dataset to obtain ferroptosis-connected mRNAs. Enrichment analysis employing KOBAS 3.0 was conducted to comprehend the biological functions and enrichment pathways of the DEGs. The generation of the protein-protein interaction (PPI) network was conducted with the aim of identifying central genes. Lastly, the coexpression and competitive endogenous RNA (ceRNA) networks were built using Cytoscape. With the help of external datasets GSE56815 to verify the reliability of the hub genes by plotting ROC curves. Results: We identified 178 DE microRNAs (miRNAs), 138 DE circular RNAs (circRNAs), and 86 ferroptosis-related mRNAs. Enrichment analysis exhibited that mRNAs were primarily connected with the signaling pathways of PI3K/Akt, metabolism, mTOR, FoxO, HIF-1, AMPK, MAPK, ferroptosis, VEGF, and NOD-like receptors. Generation of the PPI network detected eight hub genes. The circRNA/miR-23b-3p/PTEN axis may relieve PMOP by inhibiting ferroptosis through targeting the pathway of PI3K/Akt signaling, which is a vital modulatory pathway for PMOP progression. Moreover, the ROC curves ultimately indicates that the four hub genes have greater diagnostic importance in PMOP samples in contrast to the normal group samples, which may be possible markers for PMOP diagnosis. Conclusions: Bioinformatics analysis identified four hub genes, namely, PTEN, SIRT1, VEGFA, and KRAS, as potential biomarkers for PMOP diagnosis and management. Moreover, the circRNA/miR-23b-3p/PTEN axis may relieve PMOP by suppressing ferroptosis through targeting the pathway of PI3K/Akt signaling, providing a new avenue to explore the pathogenesis of PMOP.

Chlorogenic acids: A pharmacological systematic review on their hepatoprotective effects.

BACKGROUND: Liver diseases have a negative impact on global health and are a leading cause of death worldwide. Chlorogenic acids (CGAs), a family of esters formed between certain trans-cinnamic acids and quinic acid, are natural polyphenols abundant in coffee, tea, and a variety of traditional Chinese medicines (TCMs). They are reported to have good hepatoprotective effects against various liver diseases. PURPOSE: This review aims to analyze the available literature on the hepatoprotective effect of CGAs, with particular emphasis on their mechanisms. METHODS: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. PubMed and Web of Science databases were adopted to retrieve all relevant literature on CGAs for liver disease from 2013 to March 2023. RESULTS: Research has indicated that CGAs play a crucial role in improving different types of liver diseases, including drug-induced liver injury (DILI), alcoholic liver disease (ALD), metabolic (dysfunction)-associated fatty liver disease (MAFLD), cholestatic liver disease (CLD), liver fibrosis, and liver cancer. CGAs display remarkable antioxidant and anti-inflammatory effects by activating erythroid 2-related factor 2 (Nrf2) and inhibiting toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) signaling pathways. Some important molecules such as AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinases 1 and 2 (ERK1/2), and other key physiological processes like intestinal barrier and gut microbiota have also been discovered to participate in CGAs-provided amelioration on various liver diseases. CONCLUSION: In this review, different studies indicate that CGAs have an excellent protective effect against various liver diseases associated with various signaling pathways.

Research progress on the circRNA­mediated regulation of tumor angiogenesis through ceRNA mechanisms (Review).

Tumors are one of the most common fatal diseases worldwide and pose a severe threat to human health. Effective tumor prevention and treatment strategies are persistent challenges in the medical community. Angiogenesis plays a critical role in and is the basis for tumor development and metastasis. Circular RNAs (circRNAs) are novel single­stranded covalently closed RNA molecules that are widely expressed in tumors due to their structural specificity and conservation. circRNAs affect angiogenesis by functioning as microRNA sponges to regulate vascular endothelial growth factor­related pathways, thereby participating in various stages of tumor growth, invasion and proliferation. The present review summarizes the involvement of circRNAs in the regulation of tumor angiogenesis through competing endogenous RNA mechanisms, with a particular focus on the regulatory role of circRNAs in tumor angiogenesis in various systems. It is considered that circRNAs have great potential for use as tumor diagnostic markers and anti­angiogenic therapies, and are thus worthy of further research and exploration.

Chlorogenic acid ameliorated non-alcoholic steatohepatitis via alleviating hepatic inflammation initiated by LPS/TLR4/MyD88 signaling pathway.

Non-alcoholic steatohepatitis (NASH) is a severe pathological stage in non-alcoholic fatty liver disease (NAFLD) and is generally recognized to be induced by chronic inflammation. Natural compound chlorogenic acid (CGA) is well-known for its anti-inflammatory capacity. This study aimed at evaluating the alleviation of CGA on NASH and further exploring its engaged mechanism via focusing on abrogating hepatic inflammation. Our results showed that CGA had a good amelioration on NASH in vivo. CGA alleviated liver oxidative injury by inducing nuclear factor erythroid 2-related factor 2 (Nrf2) activation and reduced liver steatosis via up-regulating peroxisome proliferator-activated receptor-alpha (PPARα). CGA attenuated hepatic inflammation in vivo, but didn't decrease the elevated lipopolysaccharide (LPS) content. CGA blocked the activation of nuclear factor kappa-B (NFκB) or inflammasome both in MCDD-fed mice and in LPS-stimulated macrophages. CGA was found to directly bind to myeloid differentiation primary response 88 (MyD88), and thus competitively blocked the interaction between toll-like receptor 4 (TLR4) and MyD88, thereby abrogating hepatic inflammation initiated by LPS-TLR4-MyD88. Moreover, the CGA-provided anti-inflammatory effect was obviously disappeared in macrophages overexpressed MyD88. Hence, CGA has an excellent efficacy in improving NASH. CGA alleviated liver inflammation during NASH progression through blocking LPS-TLR4-MyD88 signaling pathway via directly binding to MyD88.

Erianin alleviated liver steatosis by enhancing Nrf2-mediated VE-cadherin expression in vascular endothelium.

Non-alcoholic fatty liver disease (NAFLD) is emerging as the most common chronic liver disease and is closely associated with metabolic syndrome. Endothelial dysfunction was involved in many metabolic diseases, but the concrete participation of hepatic vascular endothelial dysfunction in liver steatosis that is an early stage of NAFLD is still unclear. In this study, the formation of liver steatosis and the elevation of serum insulin content were observed accompanying with the decreased vascular endothelial cadherin (VE-cadherin) expression in hepatic vessels from db/db mice, Goto-Kakizaki (GK) and high-fat diet (HFD)-fed rats. Liver steatosis was obviously enhanced in mice after the application of VE-cadherin neutralizing antibody. In vitro results showed that insulin decreased VE-cadherin expression and caused endothelial barrier breakdown. Furthermore, the alteration of VE-cadherin expression was found to be positively related with the transcriptional activation of nuclear erythroid 2-related factor 2 (Nrf2), and chromatin immunoprecipitation (ChIP) assay displayed that Nrf2 could directly regulate VE-cadherin expression. Insulin reduced Nrf2 activation by decreasing sequestosome-1 (p62/SQSTM1) expression downstream of insulin receptor. Moreover, the p300-mediated Nrf2 acetylation was weakened by enhancing the competitive binding of transcription factor GATA-binding protein 4 (GATA4) to p300. Finally, we found that erianin, a natural compound, could promote VE-cadherin expression by inducing Nrf2 activation, thereby alleviating liver steatosis in GK rats. Our results suggest that hepatic vascular endothelial dysfunction owing to the VE-cadherin deficiency dependent on the reduced Nrf2 activation promoted liver steatosis, and erianin alleviated liver steatosis through enhancing Nrf2-mediated VE-cadherin expression.

Chlorogenic acid alleviated liver fibrosis in methionine and choline deficient diet-induced nonalcoholic steatohepatitis in mice and its mechanism.

Nonalcoholic steatohepatitis, one of the most common chronic liver diseases, is a progressive form of nonalcoholic fatty liver disease accompanied by the development of liver fibrosis. Chlorogenic acid (CGA) is a natural polyphenolic compound. This study aims to observe the CGA-provided alleviation on liver fibrosis in methionine and choline deficient (MCD) diet-induced nonalcoholic steatohepatitis in mice and to elucidate its engaged mechanism. CGA attenuated hepatocellular injury, decreased the elevated hepatic lipids accumulation and attenuated liver fibrosis by reducing hepatic collagen deposition in mice fed with MCD diet. CGA abrogated the activation of hepatic stellate cells (HSCs) and promoted mitochondrial biogenesis both in vivo and in vitro. Moreover, the CGA-provided inhibition on HSCs activation in vitro was obviously disappeared after the application of peroxisome proliferator-activated receptor gamma, coactivator 1alpha (PGC1α) siRNA. CGA reduced the enhanced hepatic extracellular matrix (ECM) expression and the elevated serum high-mobility group box 1 (HMGB1) content in mice fed with MCD diet. CGA decreased the HMGB1-induced ECM production in both human liver sinusoidal endothelial cells and human umbilical vein endothelial cells. CGA also weakly promoted mitochondrial biogenesis in both liver sinusoidal endothelial cells and human umbilical vein endothelial cells incubated with HMGB1. Hence, CGA ameliorated hepatic fibrosis in mice fed with MCD diet through inhibiting HSCs activation via promoting mitochondrial biogenesis and reducing the HMGB1-initiated ECM production in hepatic vascular endothelial cells.

HMGB1 induced endothelial to mesenchymal transition in liver fibrosis: The key regulation of early growth response factor 1.

BACKGROUND: Liver fibrosis has been the focus and difficulty of medical research in the world and its concrete pathogenesis remains unclear. This study aims to observe the high-mobility group box 1 (HMGB1)-induced hepatic endothelial to mesenchymal transition (EndoMT) during the development of hepatic fibrosis, and further to explore the crucial involvement of Egr1 in this process. METHODS: Carbon tetrachloride (CCl4), diosbulbin B (DB), N-acetyl-p-aminophenol (APAP) and bile duct ligation (BDL) were used to induce liver fibrosis in mice. Serum HMGB1 content, the occurrence of EndoMT and the production of extracellular matrix (ECM) in vitro and in vivo were detected by Western-blot. RESULTS: The elevated serum HMGB1 content, the occurrence of EndoMT, the production of ECM and the activation of Egr1 were observed in mice with liver fibrosis induced by CCl4, DB, APAP or BDL. HMGB1 induced EndoMT and ECM production in human hepatic sinusoidal endothelial cells (HHSECs), and then HHSECs lost the ability to inhibit the activation of hepatic stellate cells (HSCs). The hepatic deposition of collagen, the increased serum HMGB1 content and hepatic EndoMT were further aggravated in Egr1 knockout mice. Natural compound silymarin attenuated liver fibrosis in mice induced by CCl4 via increasing Egr1 nuclear accumulation, decreasing serum HMGB1 content and inhibiting hepatic EndoMT. CONCLUSION: Egr1 regulated the expression of HMGB1 that induced hepatic EndoMT, which plays an important role in the development of liver fibrosis. GENERAL SIGNIFICANCE: This study provides a novel therapeutic strategy for the treatment of liver fibrosis in clinic.

Integrating network pharmacology approach and experimental validation to reveal the alleviation of Shenkangning capsule on chronic nephritis.

ETHNOPHARMACOLOGICAL RELEVANCE: Shenkangning (SKN), a Chinese patent medicine composed by eight Chinese medicinal herbs, is commonly applied to treat chronic glomerulonephritis (CGN) in clinic. However, its mechanism is still not clear now. AIM OF THE STUDY: This study is designed to evaluate the SKN-provided alleviation on adriamycin (ADR)-induced nephropathy, to reveal its mechanism by integrating network pharmacology analysis and experimental evidences, and to further find the main drug that makes a major contribution to its efficacy. MATERIALS AND METHODS: ADR was intravenously injected to mice to induce focal segmental glomerulosclerosis (FSGS). Renal histological evaluation was conducted. The level of urinary protein, and serum amounts of creatinine, urea nitrogen (BUN) and albumin were detected. The potential mechanisms were predicted by network pharmacology analysis and further validated by Real-time polymerase chain reaction (RT-PCR), Western-blot and enzyme-linked immunosorbent assay (ELISA). RESULTS: SKN (1, 10 g/kg) improved ADR-induced nephropathy in mice. Network pharmacology results predicted that inflammation and oxidative stress were crucially involved in the SKN-provided amelioration on nephropathy. SKN reduced the activation of nuclear factor-κB (NF-κB) and the expression of some pro-inflammatory cytokines, and increased the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) and the expression of its downstream genes in ADR-induced nephropathy in mice. Furthermore, SKN also restored the reduced expression of both podocin and synaptopodin, which are podocyte-associated proteins. Further results showed that the toxic drug Danfupian (DFP) had no contribution to the SKN-provided alleviation on ADR-induced nephropathy in mice. After integrating the results from evaluating anti-inflammation, anti-oxidant and anti-injury of podocytes in vitro and from comparing the activity of the whole SKN and SKN without Astragali Radix (Huangqi, HQ) in vivo, we found that HQ played a crucial contribution to the SKN-provided amelioration on ADR-induced nephropathy in mice. CONCLUSION: SKN improved ADR-induced nephropathy through suppressing renal inflammation and oxidative stress injury via abrogating NF-κB activation and activating Nrf2 signaling pathway. HQ played a main contribution to the SKN-provided amelioration on ADR-induced nephropathy.

The water extract of Sophorae tonkinensis Radix et Rhizoma alleviates non-alcoholic fatty liver disease and its mechanism.

BACKGROUND: Sophorae tonkinensis Radix et Rhizoma is traditionally used for clearing away heat and toxic materials in China. PURPOSE: This study aims to observe the amelioration of Sophorae tonkinensis water extract (STR) against non-alcoholic fatty liver disease (NAFLD) and the engaged mechanism. METHODS: NAFLD was induced in mice fed by methionine and choline deficient (MCD) diet. Liver histological observation, Oil Red O, Masson's trichrome and F4/80 immunohistochemical staining were performed. Serum and liver biochemical parameters, hepatic gene and protein expression were detected. Cellular lipids accumulation in human normal liver l-02 and hepatoma HepRG cells were induced by 0.5 mM nonestesterified fatty acid (NEFA). The contents of matrine (MT) and oxymatrine (OMT) in STR were detected by using high-performance liquid chromatography (HPLC). Carnitine palmitoyltransferase 1A (CPT1A) expression and enzymatic activity were detected both in vivo and in vitro. RESULTS: Serum alanine/aspartate aminotransferase (ALT/AST) activity, hepatic malondialdehyde (MDA) content and liver histological observation showed that STR alleviated hepatocellular damage in mice fed with MCD diet. Hepatic triglyceride (TG), total cholesterol (TC) and NEFA amounts, and Oil Red O staining showed that STR reduced hepatic lipids accumulation in mice fed with MCD diet. STR and its main compounds including MT and OMT decreased NEFA-induced cellular lipids accumulation in hepatocytes. STR enhanced CPT1A activity both in vivo and in vitro. MT and OMT also enhanced cellular CPT1A activity in l-02 hepatocytes treated with NEFA. Moreover, the CTP1A inhibitor etomoxir (ETO) reduced the lipid-lowering activity provided by STR, MT or OMT in vitro. Liver myeloperoxidase (MPO) activity and hydroxyproline content, Masson's trichrome and F4/80 immunohistochemical staining, and hepatic mRNA expression of some molecules involved in regulating inflammation or fibrosis demonstrated that STR alleviated hepatic inflammation and liver fibrosis in mice fed with MCD diet. CONCLUSION: STR alleviated NAFLD by inhibiting hepatic inflammation and liver fibrosis, and reducing hepatic lipids accumulation through promoting fatty acids ß-oxidation by enhancing liver CPT1A activity. MT and OMT may be the main active compounds contributing to the lipid-lowering activity provided by STR.

Chlorogenic acid alleviates acetaminophen-induced liver injury in mice via regulating Nrf2-mediated HSP60-initiated liver inflammation.

Acetaminophen (APAP)-induced acute liver failure is a serious clinic issue. Our previous study showed that chlorogenic acid (CGA) alleviated APAP-induced liver inflammatory injury, but its concrete mechanism is still not clear. This study aims to elucidate the engaged mechanism involved in the CGA-provided alleviation on APAP-induced liver inflammation. CGA reduced the increased hepatic infiltration of immune cells and the elevated serum contents of high mobility group box 1 (HMGB1) and heat shock protein 60 (HSP60) in mice treated with APAP. CGA decreased the enhanced hepatic mRNA expression of some pro-inflammatory molecules in mice treated with APAP and in RAW264.7 cells stimulated with HMGB1 or HSP60. CGA attenuated liver mitochondrial injury, rescued the decreased lon protease homolog (Lon) protein expression, and reduced mitochondrial HSP60 release in mice treated with APAP. Moreover, the CGA-provided alleviation on APAP-induced liver inflammatory injury was diminished in mice treated with anti-HSP60 antibody. Further results showed that the CGA-provided alleviation on APAP-induced liver inflammation was also diminished in nuclear factor erythroid 2-related factor 2 (Nrf2) knock-out mice. Meanwhile, the CGA-provided reduce on serum HSP60 content and restore of mitochondrial Lon protein expression were all diminished in Nrf2 knock-out mice treated with APAP. In conclusion, our study revealed that CGA alleviated APAP-induced liver inflammatory injury initiated by HSP60 or HMGB1, and Nrf2 was critical for regulating the mitochondrial HSP60 release via rescuing the reduced mitochondrial Lon protein expression.

Baicalin promotes liver regeneration after acetaminophen-induced liver injury by inducing NLRP3 inflammasome activation.

Liver regeneration has become a new hotspot in the study of drug-induced liver injury (DILI). Baicalin has already been reported to alleviate acetaminophen (APAP)-induced acute liver injury in our previous study. This study aims to observe whether baicalin also promotes liver regeneration after APAP-induced liver injury and to elucidate its engaged mechanism. Baicalin alleviated APAP-induced hepatic parenchymal cells injury and enhanced the number of mitotic and proliferating cell nuclear antigen (PCNA)-positive hepatocytes in APAP-intoxicated mice. Baicalin increased hepatic PCNA and cyclinD1 expression in APAP-intoxicated mice. Baicalin induced the activation of NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome, leading to the increased hepatic expression of interleukin-18 (IL-18) and IL-1ß in APAP-intoxicated mice. The results in vitro demonstrated that IL-18 promoted the proliferation of human normal liver L-02 cells. Moreover, the baicalin-provided promotion on liver regeneration in APAP-intoxicated mice was diminished after the application of NLRP3 inhibitor MCC950 and the recombinant mouse IL-18 binding protein (rmIL-18BP). Baicalin induced the cytosolic accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2), and increased the interaction between Nrf2 with Nlrp3, ASC and pro-caspase-1 in livers from APAP-intoxicated mice. Furthermore, the baicalin-provided NLRP3 inflammasome activation and promotion on liver regeneration after APAP-induced liver injury in wild-type mice were diminished in Nrf2 knockout mice. In conclusion, baicalin promoted liver regeneration after APAP-induced acute liver injury in mice via inducing Nrf2 accumulation in cytoplasm that led to NLRP3 inflammasome activation, and then caused the increased expression of IL-18, which induced hepatocytes proliferation.

Liver Inflammatory Injury Initiated by DAMPs-TLR4-MyD88/TRIF-NFκB Signaling Pathway Is Involved in Monocrotaline-Induced HSOS.

Hepatic sinusoidal obstruction syndrome (HSOS) causes considerable morbidity and mortality in clinic. Up to now, the molecular mechanisms involved in the development of HSOS still remain unclear. Here, we report that hepatic inflammation initiated by damage-associated molecular patterns (DAMPs) plays a critical role in the development of HSOS. Monocrotaline (MCT) belongs to pyrrolizidine alkaloids. Monocrotaline-induced HSOS in mice and rats was evidenced by the increased serum alanine/aspartate aminotransferase (ALT/AST) activities, the elevated hepatic metalloproteinase 9 (MMP9) expression, and results from liver histological evaluation and scanning electron microscope observation. However, MCT-induced HSOS was markedly attenuated in myeloid differentiation primary response gene 88 (MyD88), TIR-domain-containing adapter-inducing interferon-ß (TRIF) and toll like receptor 4 (TLR4) knock-out mice. Monocrotaline increased liver myeloperoxidase activity, serum contents of proinflammatory cytokines, hepatic aggregation of immune cells, and nuclear accumulation of nuclear factor κB (NFκB). However, these inflammatory responses induced by MCT were all diminished in MyD88, TRIF, and TLR4 knock-out mice. Monocrotaline elevated serum contents of DAMPs including high mobility group box 1 (HMGB1) and heat shock protein 60 (HSP60) both in mice and in rats. HSOS was markedly exacerbated and serum contents of HMGB1 and HSP60 were elevated in nuclear factor erythroid 2-related factor 2 (Nrf2) knock-out mice treated with MCT. Our findings indicate that hepatic inflammatory injury mediated by DAMPs-initiated TLR4-MyD88/TRIF-NFκB inflammatory signal pathway plays an important role in HSOS development.

Identification of serum microRNAs as potential toxicological biomarkers for toosendanin-induced liver injury in mice.

BACKGROUND: Toosendan Fructus is traditionally used as an insecticide or digestive tract parasiticide for treating digestive parasites in China. It is recorded to have little toxicity in Chinese Pharmacopoeia and has been found to cause severe liver injury during clinical practice. PURPOSE: This study aims to identify candidate serum microRNAs (miRNAs) as potential toxicological biomarkers for reflecting the hepatotoxicity induced by toosendanin (TSN), which is the main toxic compound isolated from Toosendan Fructus METHODS: Alanine/aspartate aminotransferase (ALT/AST) activities detection and liver histological observation were performed to evaluate the liver injury induced by TSN or other hepatotoxicants in mice. miRNAs chip analysis and Real-time PCR assay were conducted to identify the altered miRNAs in serum from TSN-treated mice RESULTS: The results of serum ALT/AST and liver histological evaluation showed that TSN (10 mg/kg) induced hepatotoxicity in mice. The results of miRNAs chip showed that the expression of 81 serum miRNAs was obviously altered in mice treated with TSN for 12 h, and 22 of them have passed the further validation in serum from mice treated with TSN for both 6 h and 12 h. These 22 miRNAs were supposed to be the candidate toxicological biomarkers for TSN-induced hepatotoxicity with more sensitivity as compared to the alteration of AST or ALT activity. Moreover, the expression of miRNA-122-3p and mcmv-miRNA-m01-4-3p was not only increased in TSN-treated mice, but also increased in mice treated with other hepatotoxicants including acetaminophen (APAP), monocrotaline (MCT) and diosbuibin B (DB). Only the expression of serum miRNA-367-3p was increased in TSN-treated mice but not changed in the liver injury induced by APAP, MCT or DB CONCLUSION: miR-122-3p and mcmv-miRNA-m01-4-3p may be two commonly sensitive biomarkers for reflecting the hepatotoxicity induced by exogenous hepatotoxicants, and miR-367-3p may be a specific biomarker for reflecting the liver injury induced by TSN.