A therapeutic strategy of parthenolide in improving imiquimod-induced psoriasis-like skin inflammation targeting IL-36/NETs through skin transdermal therapeutic system

BACKGROUND

Psoriasis is an inflammatory skin disease that occurs repeatedly over time. The natural product of sesquiterpene lactones, Parthenolide (Par), is isolated from Tanacetum parthenium L. (feverfew) which has significant effects on anti-inflammatory. The therapeutic effect of the medication itself is crucial, but different routes of administration of the same drug can also produce different effects.

PURPOSE

The aim of our research sought to investigate the ameliorating effects of Par in psoriasis-like skin inflammation and its related mechanism of action.

RESULTS

In the IMQ-induced model, intragastric administration of Par reduced the Psoriasis Area and Severity Index (PASI) score, improved skin erythema, scaling, and other symptoms. And Par decreased the expression of Ki67, keratin14, keratin16 and keratin17, and increased the expression of keratin1. Par could reduce IL-36 protein expressions, meanwhile the expression of Il1b, Cxcl1 and Cxcl2 mRNA were also decreased. Par regulated the expression levels of F4/80, MPO and NE. However, skin transdermal administration of Par was more effective. Similarly, Par attenuated IL-36γ, IL-1β and caspase-1 activated by Poly(I:C) in in vitro and ex vivo. In addition, Par also reduced NE, PR3, and Cathepsin G levels in explant skin tissues.

CONCLUSION

Par ameliorated psoriasis-like skin inflammation in both in vivo and in vitro, especially after treatment with transdermal drug delivery, possibly by inhibiting neutrophil extracellular traps and thus by interfering IL-36 signaling pathway. It indicated that Par provides a new research strategy for the treatment of psoriasis-like skin inflammation and is expected to be a promising drug.

Synthesis and anti-liver fibrosis activity of imidazole and thiazole compounds containing amino acids

Four series of imidazoles (15a-g, 20c, and 20d) and thiazoles (18a-g, 22a, and 22b) possessing various amino acids were synthesized and evaluated for activin receptor-like kinase 5 (ALK5) inhibitory activities in an enzymatic assay. Among them, compounds 15g and 18c showed the highest inhibitory activity against ALK5, with IC50 values of 0.017 and 0.025 μM, respectively. Compounds 15g and 18c efficiently inhibited extracellular matrix (ECM) deposition in TGF-β-induced hepatic stellate cells (HSCs), and eventually suppressed HSC activation. Moreover, compound 15g showed a good pharmacokinetic (PK) profile with a favorable half-life (t1/2 = 9.14 h). The results indicated that these compounds exhibited activity targeting ALK5 and may have potential in the treatment of liver fibrosis; thus they are worthy of further study.

Angelica dahurica extract and its effective component bergapten alleviated hepatic fibrosis by activating FXR signaling pathway

Angelica dahurica (A. dahurica) has a wide range of pharmacological effects, including analgesic, anti-inflammatory and hepatoprotective effects. In this study, we investigated the effect of A. dahurica extract (AD) and its effective component bergapten (BG) on hepatic fibrosis and potential mechanisms. Hepatic fibrosis was induced by intraperitoneal injection with carbon tetrachloride (CCl4) for 1 week, and mice were administrated with AD or BG by gavage for 1 week before CCl4 injection. Hepatic stellate cells (HSCs) were stimulated by transforming growth factor-β (TGF-β) and cultured with AD, BG, GW4064 (FXR agonist) or Guggulsterone (FXR inhibitor). In CCl4-induced mice, AD significantly decreased serum aminotransferase, reduced excess accumulation of extracellular matrix (ECM), inhibited caspase-1 and IL-1β, and increased FXR expressions. In activated HSCs, AD suppressed the expressions of α-SMA, collagen I, and TIMP-1/MMP-13 ratio and inflammatory factors, functioning as FXR agonist. In CCl4-induced mice, BG significantly improved serum transaminase and histopathological changes, reduced ECM excessive deposition, inflammatory response, and activated FXR expression. BG increased FXR expression and inhibited α-SMA and IL-1β expressions in activated HSCs, functioning as GW4064. FXR deficiency significantly attenuated the decreasing effect of BG on α-SMA and IL-1β expressions in LX-2 cells. In conclusion, AD could regulate hepatic fibrosis by regulating ECM excessive deposition and inflammation. Activating FXR signaling by BG might be the potential mechanism of AD against hepatic fibrosis.

Targeting RXFP1 by Ligustilide: A novel therapeutic approach for alcoholic hepatic steatosis

BACKGROUND

Ligustilide (Lig) is the main active ingredient of Umbelliferae Angelicae Sinensis Radix (Chinese Angelica) and Chuanxiong Rhizoma (Sichuan lovase rhizome). Lig possesses various pharmacological properties and could treat obesity by regulating energy metabolism. However, the impact and regulatory mechanism of Lig on alcoholic hepatic steatosis remains unclear.

PURPOSE

This study aimed to explore the therapeutic effect of Lig on alcoholic hepatic steatosis and its related pharmacological mechanism.

RESULTS

With chronic and binge ethanol feeding, liver tissue damage and lipid accumulation in mice suffering alcoholic hepatic steatosis were significantly improved after Lig treatment. Lig effectively regulated the expression levels of lipid metabolism-related proteins in alcoholic hepatic steatosis. In addition, Lig reduced RXFP1 expression, inhibited the activation of NLRP3 inflammasome, and blocked NET formation. Lig reduced the infiltration of immune cells to the liver and the further prevented the occurrence of alcohol-stimulated inflammatory response in liver. Lig significantly regulated lipid accumulation in alcohol exposed AML12 cells via modulating PPARα and SREBP1. In MPMs, Lig decreased the expression of RXFP1, inhibited the activation of NLRP3 in macrophages stimulated by LPS/ATP, and slowed down the occurrence of inflammatory response.

CONCLUSION

Lig sustained lipid metabolism homeostasis in alcoholic hepatic steatosis, through inhibiting the activation of NLRP3 inflammasomes and the formation of NETs, especially targeting RXFP1 in macrophages.

Sesamol as a potential candidate for the treatment of hepatic fibrosis, based on its regulation of FXR/LXR axis-mediated inhibition of autophagy through crosstalk between hepatic cells and macrophage

BACKGROUND

Sesamol (SEM), a natural lignan compound isolated from sesame, has strong anti-oxidant property, regulating lipid metabolism, decreasing cholesterol and hepatoprotection. However, its anti-hepatic fibrosis effect and mechanisms have not been comprehensively elucidated.

HYPOTHESIS/PURPOSE

This study aims to investigate the anti-hepatic fibrosis of SEM and its underlying mechanisms.

METHOD

C57BL/6 mice with hepatic fibrosis were induced by TAA, then administrated with SEM or curcumin, respectively. HSCs were stimulated by TGF-β or conditioned medium, and then cultured with SEM, GW4064, GW3965, Rapamycin (RA) or 3-methyladenine (3-MA), respectively. Mice with hepatic fibrosis also were administrated with SEM, RA or 3-MA to estimate the effect of SEM on autophagy.

RESULTS

In vitro, SEM significantly inhibited extracellular matrix deposition, P2 × 7r-NLRP3, and inflammatory cytokines. SEM increased FXR and LXRα/β expressions and decreased MAPLC3α/β and P62 expressions, functioning as 3-MA (autophagy inhibitor). In vivo, SEM reduced serum transaminase, histopathology changes, fibrogenesis, autophagy markers and inflammatory cytokines caused by TAA. LX-2 were activated with conditioned medium from LPS-primed THP-1, which resulted in significant enhance of autophagy markers and inflammatory cytokines and decrease of FXR and LXRα/β expressions. SEM could reverse above these changes and function as 3-MA, GW4064, or GW3965. Deficiency of FXR or LXR attenuated the regulation of SEM on α-SMA, MAPLC3α/β, P62 and IL-1β in activated LX-2. In activated THP-1, deficiency of FXR could decrease the expression of LXR, and vice versa. Deficiency of FXR or LXR in activated MΦ decreased the expressions of FXR and LXR in activated LX-2. Deficiency FXR or LXR in activated MΦ also attenuated the regulation of SEM on α-SMA, MAPLC3α/β, P62, caspase-1 and IL-1β. In vivo, SEM significantly reversed hepatic fibrosis via FXR/LXR and autophagy.

CONCLUSION

SEM could regulate hepatic fibrosis by inhibiting fibrogenesis, autophagy and inflammation. FXR/LXR axis-mediated inhibition of autophagy contributed to the regulation of SEM against hepatic fibrosis, especially based on involving in the crosstalk of HSCs-macrophage. SEM might be a prospective therapeutic candidate, and its mechanism would be a new direction or strategy for hepatic fibrosis treatment.

Synthesis of and anti-fibrotic effect of pyrazole derivative J-1048: Inhibition of ALK5 as a novel approach to liver fibrosis targeting inflammation

Liver fibrosis is a worldwide challenge of health issue. Developing effective new drugs for treating liver fibrosis is of great importance. In recent years, chemically synthesized drugs have significant advantages in treating liver fibrosis. Small molecule pyrazole derivatives as activin receptor-like kinase 5 (ALK5) inhibitors have also shown anti-fibrotic and tumor growth inhibitory effects. To develop the candidate with anti-fibrotic effect, we synthesized a novel pyrazole derivative, J-1048. The inhibitory effect of J-1048 on ALK5 and p38α mitogen-activated protein (MAP) kinase activity was assessed by enzymatic assays. We established an in vivo liver fibrosis model by injecting thioacetamide (TAA) into mice and in vitro model of TGF-β stimulated hepatic stellated cells to explore the inhibition mechanisms and therapeutic potential of J-1048 as an ALK5 inhibitor in liver fibrosis. Our data showed that J-1048 inhibited TAA-induced liver fibrosis in mice by explicitly blocking the TGF-β/Smad signaling pathway. Additionally, J-1048 inhibited the production of inflammatory cytokine Interleukin-1β (IL-1β) by inhibiting the purinergic ligand-gated ion channel 7 receptor (P2X7r) -Nucleotide-binding domain-(NOD-)like receptor protein 3 (NLRP3) axis, thereby alleviating liver fibrosis. Our findings demonstrated that a novel small molecule ALK5 inhibitor, J-1048, exhibited strong potential as a clinical therapeutic candidate for liver fibrosis.

Potential skin health promoting benefits of costunolide: a therapeutic strategy to improve skin inflammation in imiquimod-induced psoriasis

Psoriasis is a recurrent inflammatory skin disease. IL-36-related cytokines are overexpressed in psoriasis, but the mechanism is not yet clear. Costunolide (Cos) is a sesquiterpenoid compound derived from the root of the traditional Chinese medicine Aucklandia lappa Decne. This study aimed to explore the mechanism of Cos on improving psoriasis-like skin inflammation. An in vivo model was established by applying imiquimod treatment to the back skin of mice, and an in vitro model was established by using polyinosinic-polycytidylic acid (Poly(I:C)) stimulated-mouse primary dermal fibroblasts to induce inflammation. The results showed that Cos improved the pathological changes of psoriasis-like skin inflammation. In addition, Cos could inhibit epidermal damage and inflammation-related expression and improve the occurrence of skin-related inflammation in both in vivo and in vitro experiments. The improvement of psoriasis-like skin inflammatory response might be through the P2X7R/IL-36 signaling pathway. Collectively, Cos has an inhibitory effect on the expression of psoriasis-like skin inflammation. This showed that Cos has potential skin health promoting benefits by preventing psoriasis-like skin inflammation.

Carnosic acid suppressed the formation of NETs in alcoholic hepatosteatosis based on P2X7R-NLRP3 axis

BACKGROUND

Alcoholic liver disease (ALD) is accompanied by a disruption of lipid metabolism and an inflammatory response in the liver during the process of disease. Carnosic acid (CA), a natural diterpene extracted from Rosmarinus officinalis (rosemary) and Salvia officinalis (sage), has more pharmacological activities, which is known to be useful in the treatment of obesity and acts by regulating energy metabolism. However, the role and regulation mechanism of CA against ALD remain unclear.

HYPOTHESIS

We hypothesized that CA might improve alcoholic-induced hepatosteatosis.

STUDY DESIGN AND METHODS

The alcoholic liver disease model was established a mouse chronic ethanol feeding by Lieber-DeCarli control liquid feed (10 d) plus a single binge with or without CA administration. AML12 cells were exposed to ethanol for 24 h. Murine peritoneal macrophages (MPM) were stimulated with LPS and ATP.

RESULTS

CA ameliorated lipid accumulation in the liver of mice in the NIAAA model, acting by inhibiting the expression of genes related to lipid synthesis. CA reduced alcohol-induced immune cell infiltration in the liver, and inhibited the activation of P2X7R-NLRP3 inflammasome, meanwhile blocked the formation of NETs in mouse livers tissue. In AML12 cells, CA attenuated the lipid accumulation triggered by ethanol stimulation, which was achieved by inhibiting the expression of SREBP1 and CA reduced the release of inflammatory factor IL-1β by inhibiting the activation of P2X7R-NLRP3. In MPM, IL-1β and HMGB1 were reduced after LPS/ATP stimulation in CA-treated cells and supernatant.

CONCLUSIONS

CA attenuated alcohol-induced fat accumulation, suppressed the formation of NETs based on P2X7R-NLRP3 axis in mouse livers. Our data indicated that CA exerted hepatoprotective effects, which might be a promising candidate.

Acanthoic acid, unique potential pimaradiene diterpene isolated from Acanthopanax koreanum Nakai (Araliaceae): A review on its pharmacology, molecular mechanism, and structural modification

Acanthoic acid (AA) is a pimaradiene diterpene isolated from the root bark of Acanthopanax koreanum Nakai (Araliaceae) with a wide range of pharmacological activities, including anti-cancer, anti-inflammatory, anti-diabetes, liver protection, gastrointestinal protection, and cardiovascular protection. In addition, AA promotes its pharmacological effects by targeting liver X receptors (LXRs), nuclear factor-kappa B (NF-κB), Toll-Like Receptor 4 (TLR4) and IL-1 receptor-associated kinase (IRAK) signaling pathways, or AMP-activated protein kinase (AMPK) signaling pathway, etc. Also, some studies focus on the structural modification of AA to improve its pharmacological activities. The review summarizes the pharmacological activities, molecular mechanism, and the structural modification of AA, which might supply information for the development of AA in the future.

Taxifolin blocks monosodium urate crystal-induced gouty inflammation by regulating phagocytosis and autophagy

Gout is a chronic disease caused by monosodium urate (MSU) crystal deposition in the joints and surrounding tissues. We examined the effects of Taxifolin, a natural flavonoid mainly existing in vegetables and fruits, on MSU-induced gout. Pretreatment with Taxifolin significantly reduced IL-1β, Caspase-1 and HMGB1 levels, upregulation of autophagy-related protein, LC3, as well as improved phagocytosis of macrophages. This study indicated that Taxifolin-attenuated inflammatory response in MSU-induced acute gout model by decreasing pro-inflammatory cytokine production and promoting the autophagy and phagocytic capacity of macrophages. Dietary supplementation with Taxifolin induces the autophagy and attenuated inflammatory response, which in consequence modulates acute gout. A preventive strategy combining dietary interventions with Taxifolin may offer a potential therapeutic alternative to pharmacological treatment to reduce inflammatory response to gout.

Modulation of IL-36-based inflammatory feedback loop through hepatocytes-derived IL-36R-P2X7R axis improves steatosis in alcoholic steatohepatitis

BACKGROUND AND PURPOSE

IL-36 is induced by proinflammatory cytokines and itself promotes inflammatory responses, shaping an IL-36-based inflammation loop. Although, hepatocytes, as "epithelial cell-like" hepatic parenchymal cells, produce IL-36 responses to drug-induced liver injury, little is known about the mechanistic role of the IL-36 signalling during the progression of alcoholic steatohepatitis (ASH). Regarding IL-36/IL-36R and P2X7R coregulates the inflammatory response, we elucidated the modulation of IL-36R-P2X7R-TLRs axis affected hepatocytes steatosis and IL-36-based inflammatory feedback loop that accompanies the onset of ASH.

EXPERIMENTAL APPROACH

C57BL/6J mice were subjected to chronic-plus-binge ethanol feeding or acute gavage with multiple doses of ethanol to establish ASH, followed by pharmacological inhibition or genetic silencing of IL-36R and P2X7R. AML12 cells or mouse primary hepatocytes were stimulated with alcohol, LPS plus ATP or Poly(I:C) plus ATP, followed by silencing of IL-36γ, IL-36R or P2X7R.

KEY RESULTS

P2X7R and IL-36R deficiency blocked the inflammatory loop, especially made by IL-36 cytokines, in hepatocytes of mice suffering from ASH. Pharmacological inhibition to P2X7R or IL-36R alleviated lipid accumulation and inflammatory response in ASH. IL-36R was indispensable for P2X7R modulated NLRP3 inflammasome activation in ASH and IL-36 led to a vicious cycle of P2X7R-driven inflammation in alcohol-exposed hepatocytes. TLR ligands promoted IL-36γ production in hepatocytes based on the synergism of P2X7R.

CONCLUSIONS AND IMPLICATIONS

Blockade of IL-36-based inflammatory feedback loop via IL-36R-P2X7R-TLRs-modulated NLRP3 inflammasome activation circumvented the steatosis and inflammation that accompanies the onset of ASH, suggesting that targeting IL-36 might serve as a novel therapeutic approach to combat ASH.

Protective role of Siberian onions against toxin-induced liver dysfunction: an insight into health-promoting effects

Siberian onions (SOs) are delicious wild vegetables. Their taste is most unique, not only like scallions but also like leeks or garlic. They also have a traditional medicinal value for anti-inflammation, anti-oxidation, and anti-pyretic analgesia, particularly facilitating hepatoprotective effects. The current study investigates the potential mechanism of SOs against toxin-induced liver dysfunction. BALB/c mice were administrated with SO or silymarin by oral gavage for one week, followed by injecting carbon tetrachloride (CCl₄) to induce hepatic fibrosis. The effect of SO against hepatic fibrosis was evaluated by examining the liver tissue for serum transaminase, oxidative stress, extracellular matrix, histological alterations, cytokine levels, and apoptosis. In vitro, HSC-T6 cells were cultured with the supernatant from Raw 264.7 cells stimulated with lipopolysaccharides, followed by SO extracts or Niclosamide (Signal Transducer and Activator of Transcription 3 (STAT3) inhibitor) at indicated time periods and doses. SO decreased serum transaminase levels and oxidative stress, and regulated the balance of ECM in CCl₄-induced mice, including α-SMA, collagen-I and TIMP-1. SO reduced the release of inflammatory factors and regulated apoptosis-associated proteins, which is related to the inhibition of STAT3 phosphorylation. Moreover, SO reduced the positive expressions of α-SMA and NLRP3 by inhibiting STAT3 phosphorylation in activated HSCs. SO could show health-promoting effects for liver dysfunction by alleviating hepatic fibrogenesis, apoptosis and inflammation in the development of hepatic fibrosis potential depending on the STAT3 signaling pathway.

Inhibition of HMGB1/TLR4 Signaling Pathway by Digitoflavone: A Potential Therapeutic Role in Alcohol-Associated Liver Disease

Digitoflavone (DG) is a natural flavonoid abundant in many fruits, vegetables, and medicinal plants. We investigated whether DG inhibits lipid accumulation and inflammatory responses in alcoholic liver disease (ALD) in vivo and in vitro. The mouse ALD model was established by chronically feeding male C57BL/6 mice an ethanol-containing Lieber-DeCarli liquid diet. In vitro, mouse peritoneal macrophages (MPMs) and mouse bone marrow-derived macrophages (BMDMs) were stimulated with LPS/ATP, whereas HepG2 cells and mouse primary hepatocytes were treated with ethanol. DG reduced the serum levels of transaminase and serum and hepatic levels of triglycerides and malondialdehyde in ALD mice. DG downregulated SREBP1 and its target genes and upregulated PPARα and its target genes in the liver of mice with ALD. DG inhibited TLR4-mediated NLRP3 inflammasome activation, consequently reversing the inflammatory response, including the production of HMGB1, IL-1β, and IL-36γ, as well as the infiltration of macrophages and neutrophils. DG blocked NLRP3/ASC/caspase-1 inflammasome activation and HMGB1 release in LPS/ATP-stimulated MPMs. When Tlr4 was knocked in LPS/ATP-stimulated BMDMs, HMGB1 production and release were blocked, and NLRP3-mediated cleavage and release of IL-1β was suppressed in Hmgb1-silenced BMDMs. DG amplified these inhibitory effects in Tlr4 or Hmgb1 knockdown BMDMs. In ethanol-exposed hepatocytes, DG reduced lipogenesis and promoted lipid oxidation by inhibiting the HMGB1-TLR4 signaling pathway while suppressing the inflammatory response induced by ethanol exposure. Our data demonstrated that DG inhibited the occurrence of lipid accumulation and the inflammatory response via the HMGB1-TLR4 axis, underscoring a promising approach and utility of DG for the treatment of ALD.

Betulin Targets Lipin1/2-Meidated P2X7 Receptor as a Therapeutic Approach to Attenuate Lipid Accumulation and Metaflammation

The present study focused on the potential mechanism of betulin (BT), a pentacyclic triterpenoid isolated from the bark of white birch (Betula pubescens), against chronic alcohol-induced lipid accumulation and metaflammation. AML-12 and RAW 264.7 cells were administered ethanol (EtOH), lipopolysaccharide (LPS) or BT. Male C57BL/6 mice were fed Lieber-DeCarli liquid diets containing 5% EtOH for 4 weeks, followed by single EtOH gavage on the last day and simultaneous treatment with BT (20 or 50 mg/kg) by oral gavage once per day. In vitro, MTT showed that 0-25 mM EtOH and 0-25 μM BT had no toxic effect on AML-12 cells. BT could regulate sterolregulatory-element-binding protein 1 (SREBP1), lipin1/2, P2X7 receptor (P2X7r) and NOD-like receptor family, pyrin domains-containing protein 3 (NLRP3) expressions again EtOH-stimulation. Oil Red O staining also indicated that BT significantly reduced lipid accumulation in EtOH-stimulated AML-12 cells. Lipin1/2 deficiency indicated that BT might mediate lipin1/2 to regulate SREBP1 and P2X7r expression and further alleviate lipid accumulation and inflammation. In vivo, BT significantly alleviated histopathological changes, reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and triglyceride (TG) levels, and regulated lipin1/2, SREBP1, peroxisome proliferator activated receptor α/γ (PPARα/γ) and PGC-1α expression compared with the EtOH group. BT reduced the secretion of inflammatory factors and blocked the P2X7r-NLRP3 signaling pathway. Collectively, BT attenuated lipid accumulation and metaflammation by regulating the lipin1/2-mediated P2X7r signaling pathway.

Luteolin attenuates hepatic injury in septic mice by regulating P2X7R-based HMGB1 release

P2X7 receptor (P2X7R) and NLRP3 cooperatively participate in inflammation and hepatocyte damage during hepatic injury induced by lipopolysaccharides (LPS). High-mobility group box 1 (HMGB1) released from immune cells in response to such stimuli plays a vital role in mediating inflammation via TLR4 and the receptor for advanced glycation end products (RAGE), a receptor for HMGB1. However, the correlation among P2X7R, RAGE and TLR4 in regulating the release of HMGB1 has not been elucidated. Increasing the number of daily foods is found to be beneficial for hepatocyte damage in septic hepatic injury. Hence, we investigated the effects of luteolin, a natural flavonoid mainly existing in vegetables and fruits, on liver injury, focusing on how luteolin participates in hepatitis based on the P2X7R-RAGE-TLR4 axis by regulating the release of HMGB1. The results demonstrated that the indicators of hepatic injury such as increased ALT, AST in the serum and infiltration of immune cells were attenuated after luteolin treatment in LPS-induced mice. Luteolin could also suppress the production and release of HMGB1 and the activation of caspase 1 both in LPS-induced mice and LPS/ATP-stimulated HepG2 cells. Collectively, luteolin reversed LPS-induced hepatic injury, especially inflammation, likely by regulating the release of HMGB1 through the P2X7R-RAGE-TLR4 axis.

Allium victorialis L. Extracts Promote Activity of FXR to Ameliorate Alcoholic Liver Disease: Targeting Liver Lipid Deposition and Inflammation

Allium victorialis L. (AVL) is a traditional medicinal plant recorded in the Compendium of Materia Medica (the Ming Dynasty). In general, it is used for hemostasis, analgesia, anti-inflammation, antioxidation, and to especially facilitate hepatoprotective effect. In recent years, it has received more and more attention due to its special nutritional and medicinal value. The present study investigates the effect and potential mechanism of AVL against alcoholic liver disease (ALD). C57BL/6 mice were fed Lieber-DeCarli liquid diet containing 5% ethanol plus a single ethanol gavage (5 g/kg), and followed up with the administration of AVL or silymarin. AML12 cells were stimulated with ethanol and incubated with AVL. AVL significantly reduced serum transaminase and triglycerides in the liver and attenuated histopathological changes caused by ethanol. AVL significantly inhibited SREBP1 and its target genes, regulated lipin 1/2, increased PPARα and its target genes, and decreased PPARγ expression caused by ethanol. In addition, AVL significantly enhanced FXR, LXRs, Sirt1, and AMPK expressions compared with the EtOH group. AVL also inhibited inflammatory factors, NLRP3, and F4/80 and MPO, macrophage and neutrophil markers. In vitro, AVL significantly reduced lipid droplets, lipid metabolism enzymes, and inflammatory factors depending on FXR activation. AVL could ameliorate alcoholic steatohepatitis, lipid deposition and inflammation in ALD by targeting FXR activation.

Modulation of HMGB1 Release in APAP-Induced Liver Injury: A Possible Strategy of Chikusetsusaponin V Targeting NETs Formation

Acetaminophen (APAP), one of the most common antipyretic analgesics, which is safe at therapeutic dose, cause acute liver injury and even death at overdose. However, the mechanism of APAP-induced inflammation in liver injury is still controversial. Therefore, effective drug intervention is urgently needed. The aim of this study was to explore the inflammatory exact mechanism of APAP, especially on neutrophils, and to study the intervention effect of Chikusetsusaponin V (CKV) derived from Panax japonicus. Establishment of hepatotoxicity model of APAP in vitro and in vivo. In vitro, HepG2 cells, AML12 cells, primary mouse hepatocytes and neutrophils were used to mimic APAP-affected hepatocytes and neutrophil. In vivo, C57BL/6 mice were administrated overdose of APAP with or without neutrophil depletion or abolishing neutrophil extracellular traps (NETs) formation. In this study, APAP stimulation increased the level of HMGB1, IL-1β and Caspase-1 in mouse liver, especially hepatocytes, which had a synergistic effect with LPS/ATP combination. NETs were formatted at early stage of APAP or HMGB1-stimulated neutrophils’ damage. Conditioned mediums from APAP-treated hepatocytes induced more significant NETs than direct APAP stimulation. Neutrophil depletion or abolishing NETs formation decreased HMGB1 level, eventually blocked hepatocytes necrosis. CKV pretreatment interfered Caspase-1 activation and HMGB1 release in APAP-damaged hepatocytes. CKV also prevented NETs formation. These results indicate that the production of HMGB1 may depend on the activation of Caspase-1 and play a key role in liver inflammation caused by APAP. The cross-dialogue between hepatocytes and neutrophils can be mediated by HMGB1. Therefore, CKV has a positive intervention effect on NETs-related inflammation in APAP-damaged liver, targeting Caspase-1-HMGB1.

Parthenolide, bioactive compound of Chrysanthemum parthenium L., ameliorates fibrogenesis and inflammation in hepatic fibrosis via regulating the crosstalk of TLR4 and STAT3 signaling pathway

The current study focused on the regulatory effects of parthenolide (PNL), a bioactive component derived from Chrysanthemum parthenium L., against hepatic fibrosis via regulating the crosstalk of toll-like receptor 4 (TLR4) and signal transducer and activator of transcription 3 (STAT3) in activated hepatic stellate cells (HSCs). HSCs or Raw 264.7 macrophages were activated by TGF-β or LPS for 1 hr, respectively, and then treated with PNL, CLI-095 (TLR4 inhibitor), or Niclosamide (STAT3 inhibitor) for the indicated time to detect the crosstalk of TLR4 and STAT3. PNL significantly decreased the expressions of α-SMA, collagen I, and the ratio of TIMP1 and MMP13 in TGF-β-activated HSCs. PNL significantly reduced the releases of pro-inflammatory cytokines, including IL-6, IL-1β, IL-1α, IL-18, and regulated signaling P2X7r/NLRP3 axis activation. PNL obviously induced the apoptosis of activated HSCs by regulating bcl-2 and caspases family. PNL significantly inhibited the expressions of TLR4 and STAT3, including their downstream signaling. PNL could regulate the crosstalk of TLR4 and STAT3, which were verified by their inhibitors in activated HSCs or Raw 264.7 cell macrophages. Thus, PNL could decrease the expressions of fibrosis markers, reduce the releases of inflammatory cytokines, and also induce the apoptosis of activated HSCs. In conclusion, PNL could bi-directionally inhibit TLR4 and STAT3 signaling pathway, suggesting that blocking the crosstalk of TLR4 and STAT3 might be the potential mechanism of PNL against hepatic fibrosis.

Genus Gentiana: A review on phytochemistry, pharmacology and molecular mechanism

ETHNOPHARMACOLOGICAL RELEVANCE

As the largest genus of Gentianaceae family, the Gentiana genus harbors over 400 species, widely distributed in the alpine areas of temperate regions worldwide. Plants from Gentiana genus are traditionally used to treat a wide variety of diseases including easing pain dispelling rheumatism, and treating liver jaundice, chronic pharyngitis and arthritis in China since ancient times. In this review, a systematic and constructive overview of the traditional uses, phytochemistry, molecular mechanisms, toxicology and pharmacological activities of the researched species of genus Gentiana is provided.

MATERIALS AND METHODS

The used information in this review is based on various databases (PubMed, Science Direct, Wiley online library, Wanfang Data, Web of Science) through a search using the keyword "Gentiana" in the period of 1981-2019. Besides, other ethnopharmacological information was acquired from Chinese herbal classic books and Chinese pharmacopoeia 2015 edition.

RESULTS

The plants from Gentiana genus have a long tradition of various medicinal uses in Europe and Asia. Phytochemical studies showed that the main bioactive components isolated from this genus includes iridoids xanthones and flavonoids. These compounds and extracts isolated from this genus show a wide range of protective activities including hepatic protection, gastrointestinal protection, cardiovascular protection, immunomodulation, joint protection, pulmonary protection, bone protection and reproductive protection. Molecular mechanism studies also indicated several potential therapeutic targets in the treatment of certain diseases by plants from this genus. Besides, natural products from this plant show no significant animal toxicity, cytotoxicity or genotoxicity.

CONCLUSION

This review summarized the traditional medicinal uses, phytochemistry, pharmacology, toxicology and molecular mechanism of genus Gentiana, providing references and research tendency for plant-based drug development and further clinical studies.

Taxifolin ameliorate high-fat-diet feeding plus acute ethanol binge-induced steatohepatitis through inhibiting inflammatory caspase-1-dependent pyroptosis

Excessive alcohol drinking and a high-fat diet (HFD) promote steatohepatitis in the comorbidity of NAFLD and AFLD. Taxifolin (TAX) is a rich dihydroxyflavone compound found in onions, milk thistle and Douglas fir. We aimed to explore the intervention mechanism of TAX on chronic steatohepatitis induced by HFD feeding plus acute ethanol binge. We established an in vivo model by HFD feeding plus a single dose of ethanol binge, and established an in vitro model by oleic acid or palmitic acid on HepG2 cells to induce lipid accumulation. TAX regulated lipid synthesis by inhibiting the expression of SREBP1 and upregulating the PPARγ level. In addition, TAX inhibited the expression of P2X7R, IL-1β, and caspase-1. Moreover, TAX reduced the expression of caspase-1 activation; thereby inhibiting the recruitment of macrophages and neutrophils. TAX also improved the inflammatory response caused by caspase-1 activation in steatotic hepatocytes. TAX exhibited an inhibitory effect on lipid accumulation and caspase-1-related pyroptosis. Collectively, TAX has therapeutic potential as an intervention of steatohepatitis induced by alcohol combined with HFD and for preventing non-alcoholic fatty liver degeneration targeting caspase-1-dependent pyroptosis.

Severe fundus lesions induced by ocular jellyfish stings: A case report

BACKGROUND

Globally, although the jellyfish population has increased in recent years, ocular jellyfish stings remain an uncommon ophthalmic emergency, and have been rarely reported. According to a few previous reports, ocular jellyfish stings may cause anterior segment disorders, and most of these injuries were self-limited and spontaneously resolved within 24 to 48 h.

CASE SUMMARY

A brother and sister both presented with severe fundus complications several years after ocular jellyfish stings and both had prolonged blurred vision. To our knowledge, such fundus lesions induced by jellyfish stings have not been reported previously.

CONCLUSION

The fundus status of patients following ocular jellyfish stings should be carefully monitored in cases of irreversible ocular damage.

20S-Protopanaxatriol Ameliorates Hepatic Fibrosis, Potentially Involving FXR-Mediated Inflammatory Signaling Cascades

Ginseng has been used as a functional food and tonic for enhancing immune power. Here, the potential protective effect of 20S-protopanaxatriol (M4), the metabolite of protopanaxatriol, against hepatic fibrosis is investigated, which could provide nutritional interventions for disease treatment. M4 could inhibit extracellular matrix (ECM) deposition and reduce the levels of proinflammatory cytokines such as caspase 1, interleukin 1 β (IL-1β), interleukin 1 receptor type 1 (IL1R1), and interleukin 6 (IL-6). M4 also significantly increased the expression of farnesoid X receptor (FXR), suppressed the purinergic ligand-gated ion channel 7 receptor (P2X7r) signaling pathway, and works as an FXR agonist, GW4064. In thioacetamide (TAA)-induced mice, M4 could attenuate the histopathological changes and significantly regulate the expression levels of FXR and P2X7r. M4 ameliorated TAA-induced hepatic fibrosis due to the reduction of P2X7r secretion, inhibition of hepatic stellate cell (HSCs) activation, and inflammation, which were all associated with FXR activation. Hence, M4 might be useful a nutritional preventive approach in antihepatic fibrosis and antihepatic inflammation.

P2X7R orchestrates the progression of murine hepatic fibrosis by making a feedback loop from macrophage to hepatic stellate cells

HSCs (hepatic stellate cells) contribute to the excessive extracellular matrix (ECM) deposition, inflammatory pathways and crucial cell-cell interactions in hepatic disease leading to fibrosis. P2x7R is considered a potential orchestrater in liver fibrosis. For this reason, this work explored the role of P2x7R in liver fibrosis and the mechanism by which P2x7R in macrophages promotes fibrogenesis. In a model of liver fibrosis induced by administration of thioacetamide (TAA), inhibition of P2x7R with its selective inhibitor A438079 reversed TAA-induced liver damage and fibrosis. The mechanism was linked to inhibition of P2x7R-NLRP3 inflammasome activation and thereby infiltration of macrophages and neutrophils into the liver. This result indicated that the P2x7R-TLR4-NLRP3 axis is involved in the process of TGF-β-mediated ECM deposition in HSCs. Ectopic overexpression of P2x7R lowered the threshold of extracellular matrix (ECM) deposition and maintained HSCs in an activated state. The culture medium of THP-1 macrophages stimulated by LPS/ATP aggravated ECM deposition in HSCs by activating P2x7R. Additionally, IL-1β secreted by LPS / ATP activated macrophages amplified fibrosis. These data indicate that P2x7R plays a key regulative role in the activation and maintenance of HSCs promoted by macrophages. Thus, pharmacological inhibition of P2x7R could be a potential therapeutic mechanism to treat human liver fibrosis.

Gentiopicroside Ameliorates the Progression from Hepatic Steatosis to Fibrosis Induced by Chronic Alcohol Intake

In current study, we aimed to investigate whether the gentiopicroside (GPS) derived from Gentiana manshurica Kitagawa could block the progression of alcoholic hepatic steatosis to fibrosis induced by chronic ethanol intake. C57BL/6 mice were fed an ethanol-containing Lieber-DeCarli diet for 4 weeks. LX-2 human hepatic stellate cells were treated with GPS 1 h prior to transforming growth factor-β (TGF-β) stimulation, and murine hepatocyte AML12 cells were pretreated by GPS 1 h prior to ethanol treatment. GPS inhibited the expression of type I collagen (collagen I), α-smooth muscle actin (α-SMA) and tissue inhibitor of metal protease 1 in ethanol-fed mouse livers with mild fibrosis. In addition, the imbalanced lipid metabolism induced by chronic ethanol-feeding was ameliorated by GPS pretreatment, characterized by the modulation of lipid accumulation. Consistently, GPS inhibited the expression of collagen I and α-SMA in LX-2 cells stimulated by TGF-β. Inhibition of lipid synthesis and promotion of oxidation by GPS were also confirmed in ethanol-treated AML12 cells. GPS could prevent hepatic steatosis advancing to the inception of a mild fibrosis caused by chronic alcohol exposure, suggesting GPS might be a promising therapy for targeting the early stage of alcoholic liver disease.

P2X7 receptor-targeted regulation by tetrahydroxystilbene glucoside in alcoholic hepatosteatosis: A new strategy towards macrophage-hepatocyte crosstalk

BACKGROUND AND PURPOSE

Regulating macrophage-hepatocyte crosstalk through P2X7 receptors has led to new pharmacological strategies to reverse alcoholic hepatosteatosis. We investigated how tetrahydroxystilbene glucoside (2354glu), isolated from Polygonum multiflorum, modulates macrophage-hepatocyte crosstalk during alcoholic hepatosteatosis.

EXPERIMENTAL APPROACH

A model of alcoholic hepatosteatosis was established by giving ethanol intragastrically to C57BL/6 mice. HepG2 cells were incubated in conditioned medium from LPS+ATP-activated THP-1 human macrophages with silenced or overexpressed P2X7 receptors. THP-1 macrophages or mouse peritoneal macrophages were pretreated with 2354glu for 1 hr prior to LPS+ATP stimulation. Western blots, RT-PCR and immunohistochemical analysis were used, along with over-expression and silencing of P2X7 receptors.

KEY RESULTS

Knockdown or overexpression of P2X7 receptors in THP-1 macrophages affected release of mature IL-1β and, subsequently, modulated lipid metabolism in HepG2 cells via the LKB-AMPK pathway. 2354glu ameliorated alcoholic hepatosteatosis in mice by regulating LKB1-AMPK-SREBP1 pathway and its target genes. Suppression of P2X7 receptor activation by 2354glu inhibited IL-1β release and reduced macrophage and neutrophil infiltration. In macrophages stimulated with LPS+ATP, expression of P2X7 receptors, caspase-1 and NF-κB, release of IL-1β, calcium influx and PI uptake were reduced by 2354glu. SIRT1-LKB1-AMPK-SREBP1 axis-mediated lipid accumulation in HepG2 cells was reduced when they were cultured with conditioned media from LPS+ATP-activated THP-1 macrophages pretreated with 2354glu.

CONCLUSION AND IMPLICATIONS

Modulation of P2X7 receptors in macrophages regulated lipid accumulation in hepatocytes during alcoholic hepatosteatosis. 2354glu might be a promising candidate that targets P2X7 receptors in macrophages interacting with hepatocytes during alcoholic hepatosteatosis.

Thymoquinone Attenuates Acetaminophen Overdose-Induced Acute Liver Injury and Inflammation Via Regulation of JNK and AMPK Signaling Pathway

Thymoquinone (TQ) is a main aromatic component of Nigella sativa L. seeds or Agastache rugosa (Fisch. & C.A.Mey.) Kuntze. The protective mechanism of TQ against acute liver injury induced by acetaminophen (APAP), however, remains unclear. We aimed to investigated the hepato-protective mechanism of TQ on the development of APAP-induced acute liver injury. Male kunming mice were pretreated with TQ or N-acetylcysteine (NAC) before a single APAP injection. Human Chang liver cells were incubated with TQ, SP600125 or AICAR in presence of APAP for 24 h. TQ pretreatment reduced levels of serum aminotransferases and increased hepatic glutathione and glutathione peroxidase activities via inhibiting CYP2E1 expression. TQ inhibited JNK, ERK and P38 phosphorylation induced by APAP. Meanwhile, TQ inhibited PI3K/mTOR signaling activation and activated AMPK phosphorylation. Moreover, TQ prevented APAP-induced hepatocytes apoptosis regulated by Bcl-2 and Bax. Furthermore, TQ inhibited STAT3 phosphorylation on APAP-induced acute liver injury. In addition, TQ significantly inhibited P2X7R protein expression and IL-1 β release. APAP-enhanced JNK phosphorylation and APAP-suppressed AMPK phosphorylation were also observed in Chang liver cells, and these changes were recovered by pretreatment with TQ, SP600125 and AICAR. Our findings suggest that TQ may actively prevent APAP-induced acute liver injury, and the effect may be mediated by JNK and AMPK signaling pathways.

Inhibition of P2X7R-NLRP3 Inflammasome Activation by Pleurotus citrinopileatus: A Possible Protective Role in Alcoholic Hepatosteatosis

Pleurotus citrinopileatus (golden oyster mushroom) is a widely used edible mushroom. We investigated the inhibitory effect of P. citrinopileatus aqueous extract against alcoholic steatohepatitis and its underlying mechanism. Acute and chronic ethanol-feeding murine models were established by intragastrically administering ethanol or feeding an ethanol-containing Lieber-DeCarli liquid diet to male C57BL/6 mice. In both models, P. citrinopileatus decreased serum alanine aminotransferase (ALT), aspartate transaminase (AST), triglyceride (TG), and hepatic TG levels. Hematoxylin and eosin (HE) and Oil Red O staining confirmed that P. citrinopileatus ameliorated both acute and chronic alcoholic hepatosteatosis, characterized by regulation of lipid-metabolism-related proteins, including sirtuin 1 (SIRT1), AMP-activated kinase (AMPK), and sterol regulatory element-binding protein (SREBP1). P. citrinopileatus reversed inflammatory response via modulating purinergic receptor P2X ligand-gated ion channel 7 (P2X7R)-NOD-like receptor pyrin domain 3 (NLRP3) inflammasome. P. citrinopileatus restored the expressions of those proteins to a normal level. In addition, HepG2 cells were incubated with P. citrinopileatus prior to ethanol stimulation. P. citrinopileatus reduced ethanol exposure-induced lipid deposition. Concomitantly, P. citrinopileatus increased AMPK and SIRT1 expressions, which were reduced by ethanol treatment. P. citrinopileatus ameliorated alcoholic hepatic steatosis and accompanied inflammatory response via regulating SIRT1-AMPK and P2X7R-NLRP3 inflammasome activation, highlighting a promising strategy and utility of P. citrinopileatus for alcoholic steatohepatitis as dietary health supplements.

Leucodin attenuates inflammatory response in macrophages and lipid accumulation in steatotic hepatocytes via P2x7 receptor pathway: A potential role in alcoholic liver disease

The current study was aimed to reveal that leucodin, a sesquiterpene lactone from Artemisia capillaris could inhibit the inflammatory response in macrophages and the lipid accumulation in hepatocytes via P2x7R-NLRP3 inflammasome activation. Several types of macrophages including mouse peritoneal macrophages, mouse bone marrow-derived macrophages and human macrophages THP-1 cells were pretreated with different concentrations of leucodin for 1 h and then stimulated with LPS and ATP. LPS plus ATP initiated IL-1β cleavage and release in mouse peritoneal macrophages and peaked at 4 h. Leucodin did not show significant toxicity within 200 μM and effectively inhibited pro-IL-1β cleavage and release of mature-IL-1β in macrophages. Also, P2x7R antagonist and caspase-1 inhibitor also decreased IL-1β release and cleavage. Additionally, leucodin suppressed P2x7R, TLR4 and NLRP3 expression in LPS/ATP-stimulated macrophages. HepG2 cells were pretreated with different concentrations of leucodin for 1 h and then exposed to ethanol for 24 h. Leucodin suppressed lipid accumulation and enhanced phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) in HepG2 cells exposed to ethanol. In addition, leucodin inhibited the expression of sterol regulatory element binding protein-1 (SREBP1) and ACC in ethanol-treated HepG2 cells. Leucodin possessed the capacity for inhibiting inflammatory response in macrophages and suppressing lipid accumulation in hepatocytes, suggesting a promising therapeutic potential targeting inflammation and lipid metabolism in alcoholic liver disease.

Ginsenoside 25-OCH3-PPD Promotes Activity of LXRs To Ameliorate P2X7R-Mediated NLRP3 Inflammasome in the Development of Hepatic Fibrosis

Ginseng is widely used in energy drinks, dietary supplements, and herbal medicines, and its pharmacological actions are related with energy metabolism. As an important modulating energy metabolism pathway, liver X receptors (LXRs) can promote the resolving of hepatic fibrosis and inflammation. The present study aims to evaluate the regulation of 25-OCH₃-PPD, a ginsenoside isolated from Panax ginseng, against hepatic fibrosis and inflammation in thioacetamide (TAA)-stimulated mice by activating the LXRs pathway. 25-OCH₃-PPD decreases serum ALT/AST levels and improves the histological pathology of liver in TAA-induced mice; attenuates transcripts of pro-fibrogenic markers associated with hepatic stellate cell activation; attenuates the levels of pro-Inflammatory cytokines and blocks apoptosis happened in liver; inhibits NLRP3 inflammasome by affecting P2X7R activation; and regulates PI3K/Akt and LKB1/AMPK-SIRT1. 25-OCH₃-PPD also facilitates LX25Rs and FXR activities decreased by TAA stimulation. 25-OCH₃-PPD also decreases α-SMA via regulation of LXRs and P2X7R-NLRP3 in vitro. Our data suggest the possibility that 25-OCH₃-PPD promotes activity of LXRs to ameliorate P2X7R-mediated NLRP3 inflammasome in the development of hepatic fibrosis.

Amelioration of Alcoholic Liver Steatosis by Dihydroquercetin through the Modulation of AMPK-Dependent Lipogenesis Mediated by P2X7R-NLRP3-Inflammasome Activation

Dihydroquercetin (TAX) is the most abundant dihydroflavone found in onions, milk thistle, and Douglas fir bark. We investigated whether TAX could inhibit lipid accumulation in alcoholic liver steatosis in vivo and in vitro. An in vivo model was established by intragastrically treating mice with ethanol, and an in vitro model was created by treating HepG2 cells with ethanol. TAX regulated SREBP1 and ACC expression by elevating LKB1 and AMPK phosphorylation. Also, TAX upregulated SIRT1 expression, which was suppressed by ethanol intake. Decreased expression of P2X7R and NLRP3 and suppressed cleavage of caspase-1 by TAX resulted in the inhibition of IL-1β production and release. Additionally, TAX reduced lipogenesis and promoted lipid oxidation via the regulation of AMPK and ACC in ethanol-treated steatotic HepG2 cells. TAX downregulated IL-1β cleavage responses to LPS and ATP stimulation in HepG2 cells. P2X7R deficiency attenuated lipid accumulation, characterized by increased AMPK activity and decreased SREBP1 expression in ethanol-treated HepG2 cells. Our data showed that TAX exhibited the ability to inhibit lipogenesis and a hepatoprotective capacity, indicating that TAX has therapeutic potential for preventing alcoholic liver steatosis.

Liver kinase B1/AMP-activated protein kinase-mediated regulation by gentiopicroside ameliorates P2X7 receptor-dependent alcoholic hepatosteatosis

BACKGROUND AND PURPOSE

Regulating P2X7 receptor-mediated activation of NLRP3 inflammasomes could be a therapeutic strategy to treat alcoholic hepatosteatosis. We investigated whether this process was modulated by gentiopicroside, the main active secoiridoid glycoside from Gentiana manshurica Kitagawa.

EXPERIMENTAL APPROACH

In vivo models of acute and chronic alcoholic hepatosteatosis were established by intragastrically administered ethanol or using chronic plus binge ethanol feeding of Lieber-DeCarli liquid diet to male C57BL/6 mice. In vitro, HepG2 cells were treated with ethanol. RAW 264.7 macrophages and murine bone marrow-derived macrophages (BMDMs) were stimulated with LPS and ATP.

KEY RESULTS

In both the acute and chronic alcohol-induced mouse hepatosteatosis models, gentiopicroside decreased serum aminotransferases and triglyceride accumulation. Up-regulated SREBP1, down-regulated PPARα and phosphorylated acetyl-CoA carboxylase caused by acute and chronic alcohol feeding were modulated by gentiopicroside, through the elevation of LKB1 and AMPK. Suppression of P2X7 receptor-NLRP3 activation by gentiopicroside inhibited IL-1β production. In ethanol-exposed HepG2 cells, gentiopicroside reduced lipogenesis and promoted lipid oxidation via activation of P2X7 receptor-NLRP3 inflammasomes. Genetic or pharmacological blockade of P2X7 receptors enhanced AMPK activity and reduced SREBP1 expression in ethanol-treated HepG2 cells. Gentiopicroside down-regulated P2X7 receptor-mediated inflammatory responses in LPS/ATP-stimulated RAW 264.7 macrophages and BMDMs. IL-1β from macrophages accelerated lipid accumulation in hepatocytes. Depleting macrophages by clodronate liposomes ameliorated alcoholic hepatosteatosis, and it was further alleviated by gentiopicroside.

CONCLUSIONS AND IMPLICATIONS

Activation of LKB1/AMPK signalling by gentiopicroside was mediated by the P2X7 receptor-NLRP3 inflammasome, suggesting the therapeutic value of blocking P2X7 receptors in the treatment of alcoholic hepatosteatosis.

Acanthoic acid suppresses lipin1/2 via TLR4 and IRAK4 signalling pathways in EtOH- and lipopolysaccharide-induced hepatic lipogenesis

Objectives

In alcoholic liver disease, alcohol and lipopolysaccharide (LPS) are major stimulation factors of hepatic lipogenesis. Our objective was to determine the protective mechanism of acanthoic acid (AA) in EtOH- and LPS-induced hepatic lipogenesis.

Methods

HSC-T6 cells were treated with ethanol (200 mm) plus LPS (1 μg/ml) for 1 h, followed by AA (10 or 20 μm) for another 6 h. C57BL/6 mice were pretreated with of AA (20 and 40 mg/kg) or equal volume of saline and then exposed to three doses of ethanol (5 g/kg body weight) within 24 h. The mice were sacrificed at 6 h after the last ethanol dosing.

Key findings

Acanthoic acid significantly decreased the expressions of α-SMA, collagen-I, SREBP-1, and lipin1/2 induced, also decreased fat droplets caused by EtOH/LPS. AA treatment decreased the protein expressions of TLR4, CD14, IRAK4, TRAF3, p-TAK1 and NF-κB increased by EtOH/LPS on HSC cells. Results in vivo were consistent with results in vitro.

Conclusions

Our data demonstrated that AA might modulate hepatic fibrosis and lipid deposition in HSC-T6 cell stimulated with ethanol combined with LPS by decreasing lipin1/2 via TLR4 and IRAK4 signalling pathways, and AA might be considered as a potential therapeutic candidate for alcoholic liver disease.

Acanthoic Acid Can Partially Prevent Alcohol Exposure-Induced Liver Lipid Deposition and Inflammation

Aims: The present study aims to detect the effect of acanthoic acid (AA) on alcohol exposure-induced liver lipid deposition and inflammation, and to explore the mechanisms. Methods: C57BL/6 mice were pretreated with single dose of AA (20 and 40 mg/kg) by oral gavage or equal volume of saline, and then exposed to three doses of ethanol (5 g/kg body weight, 25%, w/v) by gavage within 24 h. The mice were sacrificed at 6 h after the last ethanol dosing. Serum and hepatic indexes were detected by western blot, RT-PCR, and histopathological assay. AML-12 cells were pretreated with AA (5, 10, 20 μM), or AICAR (500 μM), GW3965 (1 μM), SRT1720 (6 μM), Nicotinamide (20 mM) for 2 h, respectively, and then following treated with EtOH (200 mM) and lipopolysaccharide (LPS) (10 ng/ml) for additional 48 h. Cell protein and mRNA were collected for western blot and RT-PCR. Cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) release were detected by ELISA assay. Results: It was found that AA significantly decreased acute ethanol-induced increasing of the serum ALT/AST, LDH, ALP levels, and hepatic and serum triglyceride levels, and reduced fat droplets accumulation in mice liver. AA significantly suppressed the levels of sterol regulatory element binding protein 1 (SREBP-1), cytochrome P4502E1 (CYP2E1), IL-1β, and caspase-1 induced by ethanol. Furthermore, a significant decline of sirtuin 1 (Sirt1) and liver X receptors (LXRs) levels was observed in EtOH group, compared with normal group mice. And AA pretreatment increased the Sirt1 and LXRs levels, and also ameliorated phosphorylation of liver kinase B-1 (LKB-1), adenosine monophosphate-activated protein kinase (AMPK), acetyl CoA carboxylase (ACC) proteins, compared with EtOH group. However, the levels of peroxisome proliferator activated receptor -α or -γ (PPAR-α or PPAR-γ) induced by acute ethanol were reversed by AA. In EtOH/LPS cultivated AML-12 cells, AA decreased IL-1β and TNF-α levels, lipid droplets, and SREBP-1 and CYP2E1 expressions, compared with EtOH/LPS treatment. AA also significantly increased protein expressions of Sirt1, p-LKB1, p-ACC, PPARα, and decreased protein expression of PPARγ, compared with EtOH/LPS treatment. Conclusion: Acanthoic acid can partially prevent alcohol exposure-induced liver lipid deposition and inflammation via regulation of LKB1/Sirt1/AMPK/ACC and LXRs pathways.

Protective effects of Chinese traditional medicine against liver injury and liver fibrosis and mechanisms involved

Liver injury and liver fibrosis are clinically common, and there is currently a lack of ideal drugs for these conditions. Recent studies have indicated that the effective components of traditional Chinese medicine show certain efficacy in prevention and treatment of liver injury and liver fibrosis, and the mechanisms are related to the protection of liver cells, anti-oxidation and anti-inflammation. This paper discusses the protective effects of the effective components of traditional Chinese medicine against liver injury and liver fibrosis and the mechanisms involved, with an aim to promote the development of therapeutic drugs for liver injury and liver fibrosis.

Thymoquinone, a bioactive component of Nigella sativa Linn seeds or traditional spice, attenuates acute hepatic failure and blocks apoptosis via the MAPK signaling pathway in mice

This study is the first report on hepatoprotective effect of thymoquinone induced byd-GalN/LPS. Thymoquinone alleviated the progress ofd-GalN/LPS induced acute hepatic failure via attenuating hepatocytes apoptosis and MAPK signaling pathway.

Association between EGF and VEGF functional polymorphisms and sporadic colorectal cancer in the Malaysian population

Growth factors are polypeptides that are critical for the initiation, progression, and metastasis of cancer. Most tumor cells are capable of synthesizing particular growth factors leading to constitutive pathway activation in these cells through autocrine signaling. Epidermal growth factor (EGF) is a potent mitogenic peptide that exerts direct effects on the proliferation and differentiation of tumor cells in carcinogenesis. By contrast, vascular endothelial growth factor (VEGF) is vital for the invasion and metastasis of neoplasms through the formation of new blood vessels from mature endothelial cells. In this study, we investigated the association between functional polymorphisms of both the EGF and VEGF genes and colorectal cancer (CRC) susceptibility. A total of 130 CRC patients and 212 healthy controls were recruited for this case-control study. Genotyping of genetic variants was conducted via real-time polymerase chain reaction (PCR) amplification with allele-specific TaqMan probes. None of the genotypes of the EGF +61 A>G and VEGF +936 C>T variants was significantly associated with CRC susceptibility among the Malaysian subjects evaluated (P > 0.05). The observed frequency distributions of the EGF +61 A>G polymorphism genotypes showed ethnic heterogeneity, which was not the case for the VEGF +936 C>T genotypes. In conclusion, no positive correlation between these functional polymorphisms and CRC risk was found in this Malaysian population. Studies of the EGF and VEGF genes and CRC susceptibility are scarce, and the results reported thus far differ from one population to another. Hence, more replication studies are warranted before any firm conclusions can be made.

NOD2/CARD15 variants in Malaysian patients with sporadic colorectal cancer

Colorectal cancer (CRC) is one of the most common types of cancer in both developed and developing countries. This disease is triggered by and progresses via the sequential accumulation of multiple genetic alterations. In addition, the interaction between low-penetrance genes and environmental factors can also increase the risk of developing CRC. Since inflammatory bowel diseases (IBDs) are one of the predisposing factors for CRC, IBD-related genes might, to a certain extent, be associated with cancer initiation. The nucleotide oligomerization domain 2/caspase activating recruitment domain 15 gene (NOD2/CARD15) is the most well-established gene to be associated with increased susceptibility to Crohn's disease. Thus, various studies have been performed to investigate the potential contribution of this gene to CRC risk. In this study, we aimed to determine the frequency of the Arg702Trp, Gly908Arg, 3020insC, Pro268Ser, and JW1 variants of NOD2/CARD15, and to investigate their association with CRC susceptibility. A total of 130 CRC patients and 212 healthy controls were recruited for this study. Subsequently, real-time polymerase chain reaction with TaqMan was performed for the genotyping of these NOD2/ CARD15 variants. None of the NOD2/CARD15 variants was statistically associated to CRC susceptibility in our Malaysian population. Our findings were remarkably similar to those of other Asian cohorts, which indicated that these NOD2/CARD15 variants exhibit genetic heterogeneity between Caucasian and Asian populations.

Thymoquinone alleviates thioacetamide-induced hepatic fibrosis and inflammation by activating LKB1-AMPK signaling pathway in mice

The current study was conducted to investigate the anti-fibrotic effect and its possible underlying mechanisms of thymoquinone (TQ) against hepatic fibrosis in vivo. TQ is the major active compound derived from the medicinal Nigella sativa. Liver fibrosis was induced in male Kunming mice by intraperitoneal injections of thioacetamide (TAA, 200 mg/kg). Mice were treated concurrently with TAA alone or TAA plus TQ (20 mg/kg or 40 mg/kg) given daily by oral gavage. Our data demonstrated that TQ treatment obviously reversed liver tissue damage compared with TAA alone group, characterized by less inflammatory infiltration and accumulation of extracellular matrix (ECM) proteins. TQ significantly attenuated TAA-induced liver fibrosis, accompanied by reduced protein and mRNA expression of α-smooth muscle actin (α-SMA), collagen-І and tissue inhibitor of metalloproteinase-1 (TIMP-1). TQ downregulated the expression of toll-like receptor 4 (TLR4) and remarkably decreased proinflammatory cytokine levels as well. TQ also significantly inhibited phosphatidylinositol 3-kinase (PI3K) phosphorylation. Furthermore, TQ enhanced the phosphorylation adenosine monophosphate-activated protein kinase (AMPK) and liver kinase B (LKB)-1. In conclusion, TQ may reduce ECM accumulation, and it may be at least regulated by phosphorylation of AMPK signaling pathways, suggesting that TQ may be a potential candidate for the therapy of hepatic fibrosis.

Hepatoprotective effect of cryptotanshinone from Salvia miltiorrhiza in D-galactosamine/lipopolysaccharide-induced fulminant hepatic failure

Cryptotanshinone from Salvia miltiorrhiza Bunge was investigated for hepatoprotective effects in d-galactosamine (GalN)/lipopolysaccharide (LPS)-induced fulminant hepatic failure. Cryptotanshinone (20 or 40 mg/kg) was orally administered 12 and 1h prior to GalN (700 mg/kg)/LPS (10 μg/kg) injection. The increased mortality and TNF-α levels by GalN/LPS were declined by cryptotanshinone pretreatment. In addition, cryptotanshinone attenuated GalN/LPS-induced apoptosis, characterized by the blockade of caspase-3, -8, and -9 activation, as well as the release of cytochrome c from the mitochondria. In addition, cryptotanshinone significantly suppressed JNK, ERK and p38 phosphorylation induced by GalN/LPS, and phosphorylation of TAK1 as well. Furthermore, cryptotanshinone significantly inhibited the activation of NF-κB and suppressed the production of proinflammatory cytokines. These findings suggested that hepatoprotective effect of cryptotanshinone is likely associated with its anti-apoptotic activity and the down-regulation of MAPKs and NF-κB associated at least in part with suppressing TAK1 phosphorylation.

Lack of association between TYK2 and STAT3 genes and Crohn's disease in the Malaysian population

This study aimed to investigate the potential association of TYK2 and STAT3 genes with the susceptibility to Crohn's disease (CD) among Malaysians. DNA samples were obtained from 80 CD patients and 100 healthy controls. Polymerase chain reaction-restriction fragment length polymorphism methods were employed for genotyping, followed by statistical analysis. In our current study, none of the single nucleotide polymorphisms of either TYK2 or STAT3 was statistically associated with the susceptibility to CD in our local population (P > 0.05). In contrast, there was a statistically significant association between the G/G homozygotes of the STAT3 rs2293152 and the healthy control group (χ(2) = 6.229, P < 0.05). In conclusion, our study does not support the role of the TYK2 and STAT3 genes influencing CD susceptibility.