Dioscin Activates Endoplasmic Reticulum Unfolded Protein Response for Defense Against Pathogenic Bacteria in Caenorhabditis elegans via IRE-1/XBP-1 Pathway

The unfolded protein response (UPR) is an evolutionarily conserved pathway that senses and responds to the accumulation of misfolded proteins in the endoplasmic reticulum (ER) lumen during bacterial infection. The IRE-1/XBP-1 pathway is a major branch of the UPRER that has been conserved from yeast to human. Dioscin, a steroidal saponin exhibits a broad spectrum of properties. However, whether dioscin influences the immune response and the underlying molecular mechanisms remain obscure. We find that dioscin increases resistance to Gram-negative pathogen Pseudomonas aeruginosa. Furthermore, dioscin also inhibits the growth of pathogenic bacteria. Meanwhile, dioscin enhances the resistance to pathogens by reducing bacterial burden in the intestine. Through genetic screening, we find that dioscin activates the UPRER to promote innate immunity via IRE-1/XBP-1 pathway. Intriguingly, dioscin requires the neural XBP-1 for immune response. Our findings suggest that dioscin may be a viable candidate for the treatment of infectious diseases.

Dioscin integrates regulation of monosaturated fatty acid metabolism to extend the life span through XBP-1/SBP-1 dependent manner

Delay aging, especially in healthy life extension, brought the most interest to the medical field. Searching for anti-aging drugs with relative safety profiles bring natural products in hotspot. In this study, we find that dioscin promotes the health span extension in wild-type Caenorhabditis elegans. Through the genetic screening in C. elegans, we further reveal that dioscin activates the transcription factor SBP-1/SREBP by the UPR^ER transcription factor XBP-1 to upregulate transcription of the Δ9 desaturase FAT-5 and FAT-7, resulting in increased monounsaturated fatty acid content which requires for healthy life span extension. Intriguingly, through tissue-specific knockdown, we find that dioscin modulates the health span by activating SBP-1 in the intestine. Unexpectedly, dietary supplementation of POA and OA rescues XBP-1, SBP-1 mutants-induced shortened life span phenotype. Considering the conservation of MUFAs metabolism, dioscin may promote health span in other species, including mammals. Our work suggests that dioscin might be a promising candidate for developing anti-aging agent.

Viscosity-sensitive NIR probe for in vivo imaging of early-stage hepatic fibrosis

A viscosity-sensitive and liver-targeted NIR fluorescent probe has been developed for early diagnosis of hepatic fibrosis.

Identification of NLRP3 as a covalent target of 1,6-O,O-diacetylbritannilactone against neuroinflammation by quantitative thiol reactivity profiling (QTRP)

Neuroinflammation plays a key etiological role in the progressive neuronal damage of neurodegenerative diseases. Our phenotypic-based screening discovered 1,6-O,O-diacetylbritannilactone (OABL, 1) from Inula britannica exhibited the potential anti-neuroinflammatory activity as well as a favorable blood-brain barrier penetration. 1 and its active derivative Br-OABL (2) with insert of Br at the C-14 position both modulated TLR4/NF-kB/MAPK pathways. However, proteome-wide identification of 1 binding proteins remains unclear. Here, we employed an adapted isoTOP-ABPP, quantitative thiol reactivity profiling (QTRP) approach, to identify and quantify thiol reactivity binding proteins in murine microglia BV-2 cells. We screened out 15 proteins co-targeted by 1 and 2, which are involved in cellular response to oxidative stress and negative regulation NF-κB transcription factor in biological processes. In site-specific profiling, NLRP3 was identified as a covalent target of 1 and 2 for the first time, and the Cys⁴⁸³ of NLRP3 NACHT domain was identified as one active-site of NLRP3 cysteine residues that can be covalently modified by the α-methylene-γ-lactone moiety. Furthermore, NLRP3 was validated to be directly binded by 1 and 2 by cellular thermo shift assay (CETSA) and activity-based protein profiling (ABPP), and NLRP3 functions were also verified by small interfering RNA approach. Notably, OABL treatment (i.p., 20 mg/kg/day) for 21 days reduced inflammation in 5XFAD mice brain. Together, we applied the QTRP to uncover the binding proteins of OABL in BV-2 cells, among which NLRP3 was revealed as a new covalent target of 1 and 2 against neuroinflammation.

Cytoskeleton Reorganization in EndMT-The Role in Cancer and Fibrotic Diseases

Chronic inflammation promotes endothelial plasticity, leading to the development of several diseases, including fibrosis and cancer in numerous organs. The basis of those processes is a phenomenon called the endothelial–mesenchymal transition (EndMT), which results in the delamination of tightly connected endothelial cells that acquire a mesenchymal phenotype. EndMT-derived cells, known as the myofibroblasts or cancer-associated fibroblasts (CAFs), are characterized by the loss of cell–cell junctions, loss of endothelial markers, and gain in mesenchymal ones. As a result, the endothelium ceases its primary ability to maintain patent and functional capillaries and induce new blood vessels. At the same time, it acquires the migration and invasion potential typical of mesenchymal cells. The observed modulation of cell shape, increasedcell movement, and invasion abilities are connected with cytoskeleton reorganization. This paper focuses on the review of current knowledge about the molecular pathways involved in the modulation of each cytoskeleton element (microfilaments, microtubule, and intermediate filaments) during EndMT and their role as the potential targets for cancer and fibrosis treatment.

Proteomic and molecular evidences of Il1rl2, Ric8a, Krt18 and Hsp90b1 modulation during experimental hepatic fibrosis and pomegranate supplementation

The inspection of variations in the proteomic aspects conspire the biomarker discovery in diagnostics of peculiar diseases. Recent developments in high-throughput proteomic techniques have provided leverage in the discovery of biomarkers during the etiology of various diseases. We identified potential biomarkers by utilizing proteomics, bioinformatics and gene expression studies. Meticulous assessment of collagen and hydroxyproline levels along with the glycogen and protein carbonyl levels exhibited deterioration in the N' - Nitrosodiethylamine (NDEA) administered rat livers and subsequent salubrious effect of pomegranate juice. The immunohistochemical inspection of iNOS and nitrite estimation indicated the peccant fibrotic alterations. 2D proteome profiling and MALDI-TOF MS/MS furthered the significant biomarkers to be analyzed for the gene ontology by PANTHER, cluster analysis by DAVID and network simulation by STRING 10.0. Several genes found relevant after MALDI analysis were evaluated by real-time PCR (RTPCR). Our data revealed CYP2b15, HSP70, TRFE, HPT, Il1rl2, Ric8a, Krt18, Hsp90b1 and iNOS as novel biomarkers for the mechanism of pomegranate against liver fibrosis. It can be inferred that NDEA-induced liver fibrosis actuates various biological pathways by the identified biomarkers and pomegranate juice modifies them.

Oridonin ameliorates carbon tetrachloride-induced liver fibrosis in mice through inhibition of the NLRP3 inflammasome

Liver fibrosis is characterized by the activation of hepatic stellate cells (HSCs) and accumulation of the extracellular matrix. There are limitations in the current therapies for liver fibrosis. Recently, oridonin was shown to induce apoptosis in HSCs. Thus, we aimed to determine the roles of oridonin in chronic liver injury and fibrosis. Liver fibrosis was induced by CCl4 in mice injected intraperitoneally with oridonin for 6 weeks. The administration of oridonin significantly attenuated liver injury and reduced ALT levels. In addition, Sirius Red staining and the expression of α-smooth muscle actin (α-SMA) were significantly reduced by oridonin in murine livers with fibrosis. The expression of NLRP3, caspase-1, and IL-1β was downregulated with the oridonin treatment. Furthermore, the expression of F4/80 in liver tissues was also decreased by oridonin treatment. These results demonstrate that oridonin ameliorates chronic liver injury and fibrosis. Mechanically, oridonin may inhibit the activity of the NLRP3 inflammasome and inflammation in the liver. These results highlight the potential of oridonin as a therapeutic agent for liver fibrosis.

Metabolic Signature of Hepatic Fibrosis: From Individual Pathways to Systems Biology

Hepatic fibrosis is a major cause of morbidity and mortality worldwide, as it ultimately leads to cirrhosis, which is estimated to affect up to 2% of the global population. Hepatic fibrosis is confirmed by liver biopsy, and the erroneous nature of this technique necessitates the search for noninvasive alternatives. However, current biomarker algorithms for hepatic fibrosis have many limitations. Given that the liver is the largest organ and a major metabolic hub in the body, probing the metabolic signature of hepatic fibrosis holds promise for the discovery of new markers and therapeutic targets. Regarding individual metabolic pathways, accumulating evidence shows that hepatic fibrosis leads to alterations in carbohydrate metabolism, as aerobic glycolysis is aggravated in activated hepatic stellate cells (HSCs) and the whole fibrotic liver; in amino acid metabolism, as Fischer’s ratio (branched-chain amino acids/aromatic amino acids) decreases in patients with hepatic fibrosis; and in lipid metabolism, as HSCs lose vitamin A-containing lipid droplets during transdifferentiation, and cirrhotic patients have decreased serum lipids. The current review also summarizes recent findings of metabolic alterations relevant to hepatic fibrosis based on systems biology approaches, including transcriptomics, proteomics, and metabolomics in vitro, in animal models and in humans.

Morin Hydrate Inhibits TREM-1/TLR4-Mediated Inflammatory Response in Macrophages and Protects Against Carbon Tetrachloride-Induced Acute Liver Injury in Mice

This study aims to investigate the protective effects of morin hydrate (MH) against acute liver injury induced by carbon tetrachloride (CCl₄) in mice and to elucidate the possible molecular mechanism of action. Mice were pretreated with MH (50 mg/kg body weight) or vehicle by oral gavage once daily for 5 days, followed by intraperitoneal injection of a single dose of CCl₄ (1 ml/kg in olive oil). Mice were sacrificed 24 h later; the blood and liver samples were harvested for analysis. We also used the model of lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages in vitro and examined the effects of MH and its mechanism of action on the inflammatory response. Our results revealed that MH remarkably attenuated liver histopathological alterations, serum transaminases, hepatocytes death, and inflammatory response induced by CCl₄. Importantly, MH reduced expression of the triggering receptor expressed on myeloid cells-1 (TREM-1) and toll-like receptor 4 (TLR4) both in vivo and in vitro experiments. This inhibitory effect MH on expression of the TREM-1 and TLR4 in cell culture was further heightened after TREM-1 knockdown with small interfering RNA (siRNA). Moreover, MH dramatically suppressed the inhibitor of kappa B α (IκBα) degradation and subsequent nuclear factor-kappa B (NF-κB) p65 translocation into the nucleus and NF-κB-mediated cytokines, such as tumor necrosis factor α (TNF-α), interleukin (IL)-1β, and IL-6. Additionally, MH also ameliorated CCl₄-induced oxidative stress by enhancing the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression in the injured livers. Taken together, MH has hepatoprotective activity, and this effect may be elicited by attenuating macrophage-mediated inflammatory responses via inhibition TREM-1/TLR4/NF-κB signaling and by regulating hepatic oxidative stress via enhancement Nrf2/HO-1 antioxidant pathway.

Protective Effects of Dioscin Against Doxorubicin-Induced Hepatotoxicity Via Regulation of Sirt1/FOXO1/NF-κb Signal

Doxorubicin (Dox), an antitumor antibiotic, has therapeutic effects on many kinds of tumors. However, Dox can produce some serious side effects that limit its clinical application. Thus, exploration of effective drug targets or active lead compounds against Dox-induced organ damage is necessary. Dioscin, one natural product, has potent effects against Dox-induced renal injury and cardiotoxicity. However, the effects of dioscin on Dox-induced hepatotoxicity have not been reported. In this study, the results showed that dioscin significantly ameliorated Dox-induced cell injury, reduced reactive oxygen species (ROS) level, and suppressed cell apoptosis in alpha mouse liver 12 (AML-12) cells caused by Dox. In vivo, dioscin evidently decreased the levels of alanine transaminase (ALT), aspartate transaminase (AST), malondialdehyde (MDA); increased the levels of superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GSH-Px); and alleviated liver injury. Mechanism study showed that dioscin remarkably up-regulated the expression levels of silent information regulator 1 (Sirt1) and heme oxygenase-1 (HO-1) via increase of the nuclear translocation of NF-E2-related factor 2 (Nrf2) and suppressed the expression levels of forkhead box protein O1 (FOXO1) and kelch-like ECH-associated protein-1 (Keap1) to inhibit oxidative stress. Furthermore, dioscin obviously decreased the nuclear translocation of nuclear factor κB (NF-κB) and the mRNA levels of tumor necrosis factor alpha (TNF-α), interleukin 1β (IL-1β), and interleukin 6 (IL-6) to suppress inflammation. Meanwhile, dioscin significantly regulated tumor suppressor P53 (P53) expression level and BCL-2-associated X (BAX)/BCL-2 apoptosis regulator (BCL-2) ratio to inhibit cell apoptosis. These results were further validated by knockdown of Sirt1 using siRNA silencing in AML-12 cells, which confirmed that the target of dioscin against Dox-induced hepatotoxicity was Sirt1/FOXO1/NF-κB signal. In short, our findings showed that dioscin exhibited protective effects against Dox-induced liver damage via suppression of oxidative stress, inflammation, and apoptosis, which should be developed as one new candidate for the prevention of Dox-induced liver injury in the future.

Recent Advances in the Pharmacological Activities of Dioscin

Dioscin is a typical saponin with multiple pharmacological activities. The past few years have seen an emerging interest in and growing research on this pleiotropic saponin. Here, we review the emerging pharmacological activities reported recently, with foci on its antitumor, antimicrobial, anti-inflammatory, antioxidative, and tissue-protective properties. The potential use of dioscin in therapies of diverse clinical disorders is also discussed.

Potent effects of dioscin against hepatocellular carcinoma through regulating TP53-induced glycolysis and apoptosis regulator (TIGAR)-mediated apoptosis, autophagy, and DNA damage

BACKGROUND AND PURPOSE

Dioscin shows potent effects against cancers. We aimed to elucidate its pharmacological effects and mechanisms of action on hepatocellular carcinoma (HCC) in vivo and in vitro.

EXPERIMENTAL APPROACH

Effects of dioscin were investigated in SMMC7721 and HepG2 cells, diethylnitrosamine-induced primary liver cancer in rats, and cell xenografts in nude mice. Isobaric tags for relative and absolution quantitation (iTRAQ)-based proteomics was used to find dioscin's targets and investigate its mechanism.

KEY RESULTS

In SMMC7721 and HepG2 cells dioscin markedly inhibited cell proliferation and migration, induced apoptosis, autophagy, and DNA damage. It inhibited DEN-induced primary liver cancer in rats, markedly changed body weights and restored levels of α fetoprotein, alanine transaminase, aspartate transaminase, γ-glutamyltransferase, alkaline phosphatase, and Ki67. It also inhibited growth of xenografts in mice. In SMMC7721 cells, 191 differentially expressed proteins were found after dioscin, based on iTRAQ-based assay. TP53-inducible glycolysis and apoptosis regulator (TIGAR) was identified as being significantly down-regulated by dioscin. Dioscin induced cell apoptosis, autophagy, and DNA damage via increasing expression levels of p53, cleaved PARP, Bax, cleaved caspase-3/9, Beclin-1, and LC3 and suppressing those of Bcl-2, p-Akt, p-mammalian target of rapamycin (mTOR), CDK5, p-ataxia telangiectasia-mutated gene (ATM). The transfection of TIGAR siRNA into SMMC7721 cells and xenografts in nude mice further confirmed that the potent activity of dioscin against HCC is evoked by adjusting TIGAR-mediated inhibition of p53, Akt/mTOR, and CDK5/ATM pathways.

CONCLUSIONS AND IMPLICATIONS

The data suggest that dioscin has potential as a therapeutic, and TIGAR as a drug target for treating HCC.

Proteome variation of the rat liver after static cold storage assayed in an ex vivo model

Cold storage is a common procedure for liver preservation in a transplant setting. However, during cold ischemia, the liver suffers molecular alterations that can affect its performance. Also, deleterious mechanisms set forth in the storage phase are exacerbated during reperfusion. This study aimed to identify liver proteins associated with injury during cold storage and/or normothermic reperfusion using the isolated perfused rat liver model. Livers from male rats were subjected to either (1) cold storage for 24 h, (2) ex vivo normothermic reperfusion for 90 min or (3) cold storage for 24 h followed by ex vivo normothermic reperfusion for 90 min. Then, the livers were homogenized and proteins were extracted. Protein expression between each experimental group and the control (freshly resected livers) was compared by two-dimensional (2D) gel electrophoresis. Protein identification was carried out by matrix-assisted laser desorption/ionization time-of-flight spectrometry (MALDI-TOF/TOF) using MASCOT as the search engine. 23 proteins were detected with significantly altered levels of expression among the different treatments, including molecular chaperones, antioxidant enzymes, and proteins involved in energy metabolism. Some of them have been postulated as biomarkers for liver damage while others had been identified in other organs subjected to ischemia and reperfusion injury. The whole data set will be a useful resource for studying deleterious molecular mechanisms that result in diminished liver function during storage and subsequent reperfusion.

Protective effects of combined Losartan and Nilotinib on carbon tetrachloride (CCl4)-induced liver fibrosis in rats

Tyrosine kinase inhibitors (TKIs) have been developed as therapeutic compounds for inhibiting the progression of liver fibrosis. In the present study, the simultaneous treatment of Nilotinib (TKIs) and Losartan was studied. Forty rats were divided into eight groups of fibrosis induced by carbon tetrachloride (CCl₄) and therapeutics (Nilotinib, Losartan, and combination therapy). In the end, serum parameters of the liver and gene expression analysis of transforming growth factor-β₁, its receptors (TβRII), platelet-derived growth factor, its receptors (PDGFR_β), matrix metalloproteinases (MMP-2 and MMP-9), tumor necrosis factor-α, cytochrome P450 2E1, and collagen1 type 1 were performed. The oxidant/antioxidant factors were also analyzed. Histopathology analysis along with α-SMA immunohistochemistry and hydroxyproline evaluation was also conducted for a more in-depth study. The overall results indicated a better therapeutic effect of co-treatment of Nilotinib-Losartan in comparison with the treatment of each of them alone. Interestingly, some gene and protein factors and fibrotic indices were reduced even to the normal levels of the control group. The results of this study suggest that co-administration of these two combinations, strengthens their anti-fibrotic properties and, due to the routine use of these compounds against AML and blood pressure, these compounds can be used with caution against human liver fibrosis.

Protective effect of dioscin against doxorubicin-induced cardiotoxicity via adjusting microRNA-140-5p-mediated myocardial oxidative stress

Clinical application of doxorubicin (DOX) is limited because of its cardiotoxicity. Thus, exploration of effective lead compounds against DOX-induced cardiotoxicity is necessary. The aim of the present study was to investigate the effects and possible mechanisms of dioscin against DOX-induced cardiotoxicity. The in vitro model of DOX- treated H9C2 cells and the in vivo models of DOX-treated rats and mice were used in this study. The results showed that discoin markedly increased H9C2 cell viability, decreased the levels of CK, LDH, and improved histopathological and electrocardio- gram changes in rats and mice to protect DOX-induced cardiotoxicity. Furthermore, dioscin significantly inhibited myocardial oxidative insult through adjusting the levels of intracellular ROS, MDA, SOD, GSH and GSH-Px in vitro and in vivo. Our data also indicated that dioscin activated Nrf2 and Sirt2 signaling pathways, and thereby affected the expression levels of HO-1, NQO1, Gst, GCLM, Keap1 and FOXO3a through decreasing miR-140-5p expression level. In addition, the level of intracellular ROS was significantly increased in H9C2 cells treated by DOX after miR-140-5p mimic transfection, as well as the down-regulated expression levels of Nrf2 and Sirt2, which were markedly reversed by dioscin. In conclusion, our data suggested that dioscin alleviated DOX-induced cardiotoxicity through modulating miR-140-5p-mediated myocardial oxidative stress. This natural product should be developed as a new candidate to alleviate cardiotoxicity caused by DOX in the future.

Protective effect of dioscin against doxorubicin-induced cardiotoxicity via adjusting microRNA-140-5p-mediated myocardial oxidative stress

Clinical application of doxorubicin (DOX) is limited because of its cardiotoxicity. Thus, exploration of effective lead compounds against DOX-induced cardiotoxicity is necessary. The aim of the present study was to investigate the effects and possible mechanisms of dioscin against DOX-induced cardiotoxicity. The in vitro model of DOX- treated H9C2 cells and the in vivo models of DOX-treated rats and mice were used in this study. The results showed that discoin markedly increased H9C2 cell viability, decreased the levels of CK, LDH, and improved histopathological and electrocardio- gram changes in rats and mice to protect DOX-induced cardiotoxicity. Furthermore, dioscin significantly inhibited myocardial oxidative insult through adjusting the levels of intracellular ROS, MDA, SOD, GSH and GSH-Px in vitro and in vivo. Our data also indicated that dioscin activated Nrf2 and Sirt2 signaling pathways, and thereby affected the expression levels of HO-1, NQO1, Gst, GCLM, Keap1 and FOXO3a through decreasing miR-140-5p expression level. In addition, the level of intracellular ROS was significantly increased in H9C2 cells treated by DOX after miR-140-5p mimic transfection, as well as the down-regulated expression levels of Nrf2 and Sirt2, which were markedly reversed by dioscin. In conclusion, our data suggested that dioscin alleviated DOX-induced cardiotoxicity through modulating miR-140-5p-mediated myocardial oxidative stress. This natural product should be developed as a new candidate to alleviate cardiotoxicity caused by DOX in the future.

Isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics for the investigation of the effect of Hugan Qingzhi on non-alcoholic fatty liver disease in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Hugan Qingzhi tablet (HQT), a traditional Chinese medicine formula has been adopted for preventing and treating nonalcoholic fatty liver disease (NAFLD).

AIM

In order to explore the anti-NAFLD mechanisms of HQT, iTRAQ-based proteomic was employed to investigate the expression profiles of proteins in NAFLD rats induced by high-fat diet after HQT treatment.

MATERIALS AND METHODS

The NAFLD rat model was administrated with high-fat diet (HFD) for 12weeks. HQT was administrated in a daily basis to the HFD groups. Biochemical markers, liver histology, pro-inflammatory cytokines, and oxidative stress/antioxidant biomarkers were assayed to evaluate HQT effects in HFD-induced NAFLD rats. Furthermore, the combined strategy of iTRAQ labeling with strong cation exchange-non-liquid chromatography-tandem mass spectrometry (SCX-non-LC-MS/MS) analysis were employed to explore the mechanisms of HQT's protective effect against NAFLD in rats. Western blotting was performed to verify the proteomic results.

RESULTS

The histopathologic characteristics and biochemical data showed that HQT exhibited protective effects on HFD-induced NAFLD rats. After being analyzed by the combined strategy of iTRAQ with LC-MS/MS and subsequent investigation, we identified 275 differentially expressed proteins in the HFD group, compared to the control; 207 altered proteins in the HQT high dose + HFD group, compared to the HFD group; and 316 altered proteins in the HQT high dose + HFD group, compared to the control. Based on the Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway mapping, the conclusion has reached that several pathways including microbial metabolism in diverse environments, fatty acid metabolism, inflammatory response, oxidative stress, bile secretion, and peroxisome proliferator activated receptor (PPAR) signaling pathway were closely related to the effects of HQT in HFD-induced NAFLD in rats. Furthermore, several differentially expressed proteins, including phytanoyl-CoA 2-hydroxylase (PHYH), acyl-CoA synthetase 1 long chain (ACSL1), hemopexin, Alpha-1-acid glycoprotein (ORM1), fatty acid binding protein 4 (FABP4), soluble sulphotransferase 2a1 (Sult2a1), and argininosuccinate synthase 1 (ASS1) were verified by the western blotting analysis and these results were consistent with the data obtained from the proteomics analysis.

CONCLUSIONS

Our results not only confirm that Hugan Qingzhi exhibits a significant protective effect in HFD-induced NAFLD rats but also provide a better understanding for the treatments of NAFLD.

Effect of dioscin on promoting liver regeneration via activating Notch1/Jagged1 signal pathway

BACKGROUND

Development of novel candidates to promote liver regeneration is critical important after partial hepatectomy (PH). Dioscin, a natural product, shows potent effect on liver protection in our previous works.

PURPOSE

This work aimed to investigate the effect and underlying mechanisms of dioscin on liver regeneration.

METHODS

The promoting proliferation effects of dioscin on mouse hepatocytem AML12 cells, rat primary hepatocytes, rats and mice after 70% PH were evaluated.

RESULTS

Dioscin significantly promoted proliferation of rat primary hepatocytes and AML12 cells through MTT, BrdU and PCNA staining assays. Meanwhile, dioscin rapidly recovered the liver to body weight ratios, declined ALT and AST levels, and relieved hepatocytes necrosis compared with 70% PH operation groups in rats and mice. Mechanistic test showed that dioscin significantly increased Notch1 and Jagged1 levels, and accelerated γ-secretase activity by up-regulating PS1 expression, leading to nuclear translocation of Notch1 intracellular domain (NICD1). Subsequently, the significant activation of Notch-dependent target genes (Hey1, Hes1, EGFR, VEGF), and cell-cycle regulatory proteins (CyclinD1, CyclinE1, CDK4 and CDK2) were all recognized. In addition, these results were further confirmed by Notch1 siRNA silencing and inhibition of γ-secretase by DAPT (a well-characterized γ-secretase inhibitor) in vitro.

CONCLUSIONS

Dioscin, as a novel efficient γ-secretase activator, NICD1 nucleus translocation promoter and cell cycle regulator, markedly activated Notch1/Jagged1 pathway to promote hepato-proliferation. Our findings provide novel insights into dioscin as a natural product with facilitating liver regeneration after PH.

Chlorogenic Acid Inhibits Liver Fibrosis by Blocking the miR-21-Regulated TGF-β1/Smad7 Signaling Pathway in Vitro and in Vivo

Aims: Chlorogenic acid (CGA) is a phenolic acid that has a wide range of pharmacological effects. However, the protective effects and mechanisms of CGA on liver fibrosis are not clear. This study explored the effects of CGA on miR-21-regulated TGF-β1/Smad7 liver fibrosis in the hepatic stellate LX2 cell line and in CCl4-induced liver fibrosis in Sprague-Dawley rats.

Methods: The mRNA expression of miR-21, Smad7, connective tissue growth factor (CTGF), α-smooth muscle actin (α-SMA), tissue inhibitor of metalloproteinase 1 (TIMP-1), matrix metalloproteinase-9 (MMP-9), and transforming growth factor-β1 (TGF-β1) and the protein levels of Smad2, p-Smad2, Smad3, p-Smad3, Smad2/3, p-Smad2/3, Smad7, CTGF, α-SMA, TIMP-1, MMP-9 and TGF-β1 were assayed in LX2 cells and liver tissue. The effects of CGA after miR-21 knockdown or overexpression were analyzed in LX2 cells. The liver tissue and serum were collected for histopathological examination, immunohistochemistry (IHC) and ELISA.

Results: The mRNA expression of miR-21, CTGF, α-SMA, TIMP-1, and TGF-β1 and the protein expression of p-Smad2, p-Smad3, p-Smad2/3, CTGF, α-SMA, TIMP-1, and TGF-β1 were inhibited by CGA both in vitro and in vivo. Meanwhile, CGA elevated the mRNA and protein expression of Smad7 and MMP-9. After miR-21 knockdown and overexpression, the downstream molecules also changed accordingly. CGA also lessened the degree of liver fibrosis in the pathological manifestation and reduced α-SMA and collagen I expression in liver tissue and TGF-β1 in serum. Conclusion: CGA might relieve liver fibrosis through the miR-21-regulated TGF-β1/Smad7 signaling pathway, which suggests that CGA might be a new anti-fibrosis agent that improves liver fibrosis.

Discovery of a Potential Plasma Protein Biomarker Panel for Acute-on-Chronic Liver Failure Induced by Hepatitis B Virus

Hepatitis B virus (HBV)-associated acute-on-chronic liver failure (HBV-ACLF), characterized by an acute deterioration of liver function in the patients with chronic hepatitis B (CHB), is lack of predicting biomarkers for prognosis. Plasma is an ideal sample for biomarker discovery due to inexpensive and minimally invasive sampling and good reproducibility. In this study, immuno-depletion of high-abundance plasma proteins followed by iTRAQ-based quantitative proteomic approach was employed to analyze plasma samples from 20 healthy control people, 20 CHB patients and 20 HBV-ACLF patients, respectively. As a result, a total of 427 proteins were identified from these samples, and 42 proteins were differentially expressed in HBV-ACLF patients as compared to both CHB patients and healthy controls. According to bioinformatics analysis results, 6 proteins related to immune response (MMR), inflammatory response (OPN, HPX), blood coagulation (ATIII) and lipid metabolism (APO-CII, GP73) were selected as biomarker candidates. Further ELISA analysis confirmed the significant up-regulation of GP73, MMR, OPN and down-regulation of ATIII, HPX, APO-CII in HBV-ACLF plasma samples (p < 0.01). Moreover, receiver operating characteristic (ROC) curve analysis revealed high diagnostic value of these candidates in assessing HBV-ACLF. In conclusion, present quantitative proteomic study identified 6 novel HBV-ACLF biomarker candidates and might provide fundamental information for development of HBV-ACLF biomarker.

Drugs and Targets in Fibrosis

Fibrosis contributes to the development of many diseases and many target molecules are involved in fibrosis. Currently, the majority of fibrosis treatment strategies are limited to specific diseases or organs. However, accumulating evidence demonstrates great similarities among fibroproliferative diseases, and more and more drugs are proved to be effective anti-fibrotic therapies across different diseases and organs. Here we comprehensively review the current knowledge on the pathological mechanisms of fibrosis, and divide factors mediating fibrosis progression into extracellular and intracellular groups. Furthermore, we systematically summarize both single and multiple component drugs that target fibrosis. Future directions of fibrosis drug discovery are also proposed.

Dioscin induces prostate cancer cell apoptosis through activation of estrogen receptor-β

Recent researches have shown that estrogen receptor-β (ERβ) activator may be a potent anticancer agent for prostate cancer (PCa), and our previous study also indicated that dioscin can upregulate the expression of ERβ in MC3T3-E1 cell. In the present work, the activity and mechanism of dioscin, a natural product, against PCa were investigated. The results showed that dioscin markedly inhibited cell viability, colony formation, motility and induced apoptosis in PC3 cells. Moreover, dioscin disrupted the formation of PC3 cell-derived mammospheres and reduced aldehyde dehydrogenase (ALDH) level and the CD133⁺/CD44⁺ cells, indicating that dioscin had a potent inhibitory activity on prostate cancer stem cells (PCSCs). In vivo results also showed that dioscin significantly suppressed the tumor growth of PC3 cell xenografts in nude mice. Furthermore, mechanism investigation showed that dioscin markedly upregulated ERβ expression level, subsequently increased prolyl hydroxylase 2 level, decreased the levels of hypoxia-inducible factor-1α, vascular endothelial growth factor A and BMI-1, and thus induced cell apoptosis by regulating the expression levels of caspase-3 and Bcl-2 family proteins. In addition, transfection experiment of ERβ-siRNA further indicated that diosicn showed excellent activity against PCa in vitro and in vivo by increasing ERβ expression level. The co-immunoprecipitation (Co-IP) results further suggested that dioscin promoted the interaction of c-ABL and ERβ, but did not change c-ABL expression. Moreover, the molecular docking assay showed that dioscin processed powerful affinity toward to ERβ mainly through the strong hydrogen bonding and hydrophobic effects, and the actions of dioscin on ERβ activation and tumor cells inhibition were significantly weakened in the mutational (Phe-336, Phe-468) PC3 cells. Collectively, these findings proved that dioscin exerted efficient anti-PCa activity via activation of ERβ, which should be developed as an efficient candidate in clinical for treating this cancer in the future.

Diosmin attenuates radiation-induced hepatic fibrosis by boosting PPAR-γ expression and hampering miR-17-5p-activated canonical Wnt-β-catenin signaling

BACKGROUND

Liver fibrosis is one of the major complications from upper right quadrant radiotherapy. MicroRNA-17-5p (miR-17-5p) is hypothesized to act as a regulator of hepatic stellate cell (HSCs) activation by activation of the canonical Wnt-β-catenin pathway. Diosmin (Dios), a citrus bioflavonoid, is known to possess potent antioxidant, anti-inflammatory, and anti-apoptotic properties.

PURPOSE

To explore the molecular mechanisms that underlie radiation-induced liver fibrosis, and to evaluate the possible influence of Dios on the miR-17-5p-Wnt-β-catenin signaling axis during fibrogenesis provoked by irradiation (IRR) in rats. Also, the effect of Dios on hepatic peroxisome proliferator activated receptor-γ (PPAR-γ) expression as a regulator for HSC activation was considered.

METHODS

We administered 100 mg·(kg body mass)^-1·day^-1 (per oral) of Dios were administered to IRR-exposed rats (overall dose of 12 Gy on 6 fractions of 2 Gy each) for 6 successive weeks.

RESULTS

Data analysis revealed that Dios treatment mitigated oxidative stress, enhanced antioxidant defenses, alleviated hepatic inflammatory responses, abrogated pro-fibrogenic cytokines, and stimulated PPAR-γ expression. Dios treatment repressed the miR-17-5p activated Wnt-β-catenin signaling induced by IRR. Moreover, Dios treatment restored the normal hepatic architecture and reversed pathological alterations induced by IRR.

CONCLUSION

We hypothesize that the stimulation of PPAR-γ expression and interference with miR-17-5p activated Wnt-β-catenin signaling mediates the antifibrotic properties of Dios.

Personalized Medicine in Ocular Fibrosis: Myth or Future Biomarkers

Significance: Fibrosis-related events play a part in the pathogenesis or failure of treatment of virtually all the blinding diseases around the world, and also account for over 40% of all deaths. It is well established that the eye and other tissues of some group of patients, for example Afro-Caribbean people, scar worse than others. However, there is a current lack of reliable biomarkers to stratify the risk of scarring and postsurgical fibrosis in the eye.

Recent Advances: Recent studies using genomics, proteomics, metabolomics, clinical phenotyping, and high-resolution in vivo imaging techniques have revealed potential novel biomarkers to identify and stratify patients at risk of scarring in different fibrotic eye diseases.

Critical Issues: Most of the studies, to date, have been done in animals or small cohorts of patients and future research is needed to validate these results in large longitudinal human studies. Detailed clinical phenotyping and effective biobanking of patient tissues will also be critical for future biomarker research in ocular fibrosis.

Future Directions: The ability to predict the risk of scarring and to tailor the antifibrotic treatment regimen to each individual patient will be an extremely useful tool clinically to prevent undertreating, or exposing patients to unnecessary treatments with potential side effects. An exciting future prospect will be to use new advances in genotyping, namely next-generation whole genome sequencing like RNA-Seq, to develop a customized gene chip in ocular fibrosis. Successful translation of future biomarkers to benefit patient care will also ultimately require a strong collaboration between academics, pharmaceutical, and biotech companies.

Dioscin reduces ovariectomy-induced bone loss by enhancing osteoblastogenesis and inhibiting osteoclastogenesis

Our previous studies showed that dioscin can promote osteoblasts proliferation and differentiation in vitro, but its anti-osteoporosis effect in vivo and the underlying mechanisms remain unclear. In the present work, the results showed that dioscin significantly increased the viability of MC3T3-E1 cells, ALP level and alizarin red S staining area, markedly decreased the numbers of RANKL-induced TRAP-positive multinucleated cells and bone resorption pits formation, enhanced the levels of some osteogenic markers including COL1A2, ALP and OC, which suggested that dioscin clearly promoted osteoblasts proliferation and suppressed osteoclasts formation. In vivo experiments demonstrated that dioscin obviously reduced OVX-induced body weight increase, and improved the biochemical indexes including ALP, StrACP, OC, DPD/Cr, HOP/Cr, BMD, biomechanics and microarchitecture. Moreover, H&E, TB, TRAP staining, and fluorescent double labeling tests indicated that dioscin enhanced osteoblastogenesis and inhibited osteoclastogenesis. Further researches demonstrated that dioscin promoted osteoblastogenesis through up-regulating OPG/RANKL ratio, and inhibited osteoclastogenesis through down-regulating the levels of RANKL induced TRAF6 and the downstream signal molecules including MAPKs, Akt, NF-κB, AP-1, cathepsin K and NFATc1. In addition, dioscin also inhibited TLR4/MyD88 pathway to decrease the levels of TRAF6 and the related proteins. These findings provide new insights to elucidate the effects of dioscin against OVX-induced bone loss, which should be developed as a potential candidate for treating postmenopausal osteoporosis in the future.

iTRAQ-based quantitative proteomic analysis for identification of biomarkers associated with emodin against severe acute pancreatitis in rats

Emodin has potent actions against SAP injury by inhibiting the HTRA1/TGF-β1 signaling pathway and subsequent inflammatory responses.