BACKGROUND C23,an oligo-peptide derived from cold-inducible RNA-binding protein(CIRP),has been reported to inhibit tissue inflammation,apoptosis and fibrosis by binding to the CIRP receptor;however,there are few repor...BACKGROUND C23,an oligo-peptide derived from cold-inducible RNA-binding protein(CIRP),has been reported to inhibit tissue inflammation,apoptosis and fibrosis by binding to the CIRP receptor;however,there are few reports on its role in liver fibrosis and the underlying mechanism is unknown.AIM To explore whether C23 plays a significant role in carbon tetrachloride(CCl4)-induced liver fibrosis.METHODS CCl4 was injected for 6 weeks to induce liver fibrosis and C23 was used beginning in the second week.Masson and Sirius red staining were used to examine changes in fiber levels.Inflammatory factors in the liver were detected and changes inα-smooth muscle actin(α-SMA)and collagen I expression were detected via immu-nohistochemical staining to evaluate the activation of hematopoietic stellate cells(HSCs).Western blotting was used to detect the activation status of the trans-forming growth factor-beta(TGF-β)/Smad3 axis after C23 treatment.RESULTS CCl4 successfully induced liver fibrosis in mice,while tumor necrosis factor-alpha(TNF-α),IL(interleukin)-1β,and IL-6 levels increased significantly and the IL-10 level decreased significantly.Interestingly,C23 inhibited this process.On the other hand,C23 significantly inhibited the activation of HSCs induced by CCl4,which inhibited the expression ofα-SMA and the synthesis of collagen I.In terms of mechanism,C23 can block Smad3 phosphorylation significantly and inhibits INTRODUCTION At present there is no specific and effective drug for treating liver fibrosis caused by acute or chronic injury.Although preclinical research has made breakthroughs,their suitability as clinical treatments is still unknown.The activation of hepatic stellate cells(HSCs)caused by chronic inflammation is a key process in the development of liver fibrosis and activated HSCs expressα-smooth muscle actin(α-SMA)and transdifferentiate into myofibroblasts with proliferation,migration and secretion abilities,synthesizing the extracellular matrix to deposit in the hepatocyte space and subse-quently forming liver fibrosis[1].Although therapeutic strategies have improved due to past few efforts there is no ideal treatment for hepatic fibrosis[2].Extracellular cold inducible RNA binding protein(CIRP)has been shown to play a role in various acute and chronic inflammatory diseases by promoting tissue inflammation and apoptosis and inducing fibrosis through its receptor Toll-like receptor 4(TLR4)[3].C23 is a recognized competitive inhibitor of CIRP that can competitively bind to CIRP receptors and reduce tissue damage in inflammatory diseases[4].C23 has been shown to significantly reduce serum tumor necrosis factor-alpha(TNF-α),IL(interleukin)-6 and IL-1βlevels.In addition,it can reduce tissue TLR4,TNF-α,IL-6 and IL-1βlevels and inhibit the colocalization of CIRP and TLR4,which plays a significant role in systemic inflammation[5].Re-search has shown that CIRP induces the inflammatory phenotype of lung fibroblasts in a TLR4-dependent manner[6].On the other hand,CIRP is associated with markers of fibrosis andα-SMA is significantly positively correlated with CIRP.Cirp-/-mice exhibit attenuated expression ofα-SMA and collagen(COL1A1 and COL3A1),decreased hydroxyproline content,decreased histological fibrosis scores,and improved pulmonary hypertension[7].C23 inhibited the release of TNF-α,the degradation of IκB and the nuclear translocation of NF-κB in CIRP-stimulated macrophages in a dose-dependent manner and C23 treatment significantly increased the serum levels of lactic dehydrogenase,alanine ami-notransferase,IL-6,TNF-αand IL-1βin septic CLP mice[8].Based on previous research we hypothesized that C23 might alleviate liver fibrosis by inhibiting acute and chronic inflammation.As a selective hepatotoxic chemical carbon tetrachloride(CCl4).can induce inflammation and activate HSCs,promoting liver fibrosis.This study reveals the role and mechanism of C23 in CCl4-induced liver fibrosis in mice.at room temperature for 30 minutes.The gray value of each group was calculated after chemiluminescence.展开更多
基金Supported by The Panzhihua Science and Technology Planning Project of China,No.2023ZD-S-57.
文摘BACKGROUND C23,an oligo-peptide derived from cold-inducible RNA-binding protein(CIRP),has been reported to inhibit tissue inflammation,apoptosis and fibrosis by binding to the CIRP receptor;however,there are few reports on its role in liver fibrosis and the underlying mechanism is unknown.AIM To explore whether C23 plays a significant role in carbon tetrachloride(CCl4)-induced liver fibrosis.METHODS CCl4 was injected for 6 weeks to induce liver fibrosis and C23 was used beginning in the second week.Masson and Sirius red staining were used to examine changes in fiber levels.Inflammatory factors in the liver were detected and changes inα-smooth muscle actin(α-SMA)and collagen I expression were detected via immu-nohistochemical staining to evaluate the activation of hematopoietic stellate cells(HSCs).Western blotting was used to detect the activation status of the trans-forming growth factor-beta(TGF-β)/Smad3 axis after C23 treatment.RESULTS CCl4 successfully induced liver fibrosis in mice,while tumor necrosis factor-alpha(TNF-α),IL(interleukin)-1β,and IL-6 levels increased significantly and the IL-10 level decreased significantly.Interestingly,C23 inhibited this process.On the other hand,C23 significantly inhibited the activation of HSCs induced by CCl4,which inhibited the expression ofα-SMA and the synthesis of collagen I.In terms of mechanism,C23 can block Smad3 phosphorylation significantly and inhibits INTRODUCTION At present there is no specific and effective drug for treating liver fibrosis caused by acute or chronic injury.Although preclinical research has made breakthroughs,their suitability as clinical treatments is still unknown.The activation of hepatic stellate cells(HSCs)caused by chronic inflammation is a key process in the development of liver fibrosis and activated HSCs expressα-smooth muscle actin(α-SMA)and transdifferentiate into myofibroblasts with proliferation,migration and secretion abilities,synthesizing the extracellular matrix to deposit in the hepatocyte space and subse-quently forming liver fibrosis[1].Although therapeutic strategies have improved due to past few efforts there is no ideal treatment for hepatic fibrosis[2].Extracellular cold inducible RNA binding protein(CIRP)has been shown to play a role in various acute and chronic inflammatory diseases by promoting tissue inflammation and apoptosis and inducing fibrosis through its receptor Toll-like receptor 4(TLR4)[3].C23 is a recognized competitive inhibitor of CIRP that can competitively bind to CIRP receptors and reduce tissue damage in inflammatory diseases[4].C23 has been shown to significantly reduce serum tumor necrosis factor-alpha(TNF-α),IL(interleukin)-6 and IL-1βlevels.In addition,it can reduce tissue TLR4,TNF-α,IL-6 and IL-1βlevels and inhibit the colocalization of CIRP and TLR4,which plays a significant role in systemic inflammation[5].Re-search has shown that CIRP induces the inflammatory phenotype of lung fibroblasts in a TLR4-dependent manner[6].On the other hand,CIRP is associated with markers of fibrosis andα-SMA is significantly positively correlated with CIRP.Cirp-/-mice exhibit attenuated expression ofα-SMA and collagen(COL1A1 and COL3A1),decreased hydroxyproline content,decreased histological fibrosis scores,and improved pulmonary hypertension[7].C23 inhibited the release of TNF-α,the degradation of IκB and the nuclear translocation of NF-κB in CIRP-stimulated macrophages in a dose-dependent manner and C23 treatment significantly increased the serum levels of lactic dehydrogenase,alanine ami-notransferase,IL-6,TNF-αand IL-1βin septic CLP mice[8].Based on previous research we hypothesized that C23 might alleviate liver fibrosis by inhibiting acute and chronic inflammation.As a selective hepatotoxic chemical carbon tetrachloride(CCl4).can induce inflammation and activate HSCs,promoting liver fibrosis.This study reveals the role and mechanism of C23 in CCl4-induced liver fibrosis in mice.at room temperature for 30 minutes.The gray value of each group was calculated after chemiluminescence.
