Background:Liver regeneration is a fundamental process for sustained body homeostasis and liver function recovery after injury.Emerging evidence demonstrates that myeloid cells play a critical role in liver regenerati...Background:Liver regeneration is a fundamental process for sustained body homeostasis and liver function recovery after injury.Emerging evidence demonstrates that myeloid cells play a critical role in liver regeneration by secreting cytokines and growth factors.Peroxisome proliferator-activated receptorα(PPARα),the target of clinical lipid-lowering fibrate drugs,regulates cell metabolism,proliferation,and survival.However,the role of myeloid PPARαin partial hepatectomy(PHx)-induced liver regeneration remains unknown.Methods:Myeloid-specific PPARa-deficient(Ppara^(Mye−/−))mice and the littermate controls(Ppara^(fl/fl))were subjected to sham or 2/3 PHx to induce liver regeneration.Hepatocyte proliferation and mitosis were assessed by immunohistochemical(IHC)staining for 5-bromo-2'-deoxyuridine(BrdU)and Ki67 as well as hematoxylin and eosin(H&E)staining.Macrophage and neutrophil infiltration into livers were reflected by IHC staining for galectin-3 and myeloperoxidase(MPO)as well as flow cytometry analysis.Macrophage migration ability was evaluated by transwell assay.The mRNA levels for cell cycle or inflammation-related genes were measured by quantitative real-time RT-PCR(qPCR).The protein levels of cell proliferation related protein and phosphorylated signal transducer and activator of transcription 3(STAT3)were detected by Western blotting.Results:Ppara^(Mye−/−)mice showed enhanced hepatocyte proliferation and mitosis at 32 h after PHx compared with Ppara^(fl/fl)mice,which was consistent with increased proliferating cell nuclear antigen(Pcna)mRNA and cyclinD1(CYCD1)protein levels in Ppara^(Mye−/−)mice at 32 h after PHx,indicating an accelerated liver regeneration in Ppara^(Mye−/−)mice.IHC staining showed that macrophages and neutrophils were increased in Ppara^(Mye−/−)liver at 32 h after PHx.Livers of Ppara^(Mye−/−)mice also showed an enhanced infiltration of M1 macrophages at 32 h after PHx.In vitro,Ppara-deficient bone marrow-derived macrophages(BMDMs)exhibited markedly enhanced migra展开更多
Signal transducer and activator of transcription 3（STAT3） is a dual functional transcription factor with the functions of signal transduction and transcription regulation. It is reported that the expression of STAT3...Signal transducer and activator of transcription 3（STAT3） is a dual functional transcription factor with the functions of signal transduction and transcription regulation. It is reported that the expression of STAT3 in ovarian cancer is significantly higher and STAT3 can facilitate ovarian cancer growth and metastasis. To clarify the definite effect and molecular mechanism of STAT3 involved in ovarian cancer growth and metastasis, STAT3 expression was significantly downregulated by transfecting ovarian cancer model SK-OV-3 cells with the plasmid vector which express specific RNAi that targets human STAT3. The downregulated STAT3 not only decreased the invasion and migration but also inhibited the proliferation of SK-OV-3 cells. Western blot assay shows that the expression of vascular endothelial growth factor（VEGF） and that of Survivin were reduced in the cells with the plasma vector expressing specific RNAi that targets human STAT3. These results demonstrate that STAT3 involved in the invasion and migration of SK-OV-3 regulates the expression of VEGF and Survivin. In addition, VEGF and Survivin could play an important role in ovarian cancer growth and metastasis.展开更多
The Janus kinase(JAK)/signal transducer and activator of transcription 3(STAT3)regulates the expression of various critical mediators of cancer and is considered as one of the central communication nodes in cell growt...The Janus kinase(JAK)/signal transducer and activator of transcription 3(STAT3)regulates the expression of various critical mediators of cancer and is considered as one of the central communication nodes in cell growth and survival.Marine natural products(MNP)represent great resources for discovery of bioactive lead compounds,especially anti-cancer agents.Through the medium-throughput screening of our in-house MNP library,Pretrichodermamide B,an epidithiodiketopiperazine,was identified as a JAK/STAT3 signaling inhibitor.Further studies identified that Pretrichodermamide B directly binds to STAT3,preventing phosphorylation and thus inhibiting JAK/STAT3 signaling.Moreover,it suppressed cancer cell growth,in vitro,at low micromolar concentrations and demonstrated efficacy in vivo by decreasing tumor growth in a xenograft mouse model.In addition,it was shown that Pretrichodermamide B was able to induce cell cycle arrest and promote cell apoptosis.This study demonstrated that Pretrichodermamide B is a novel STAT3 inhibitor,which should be considered for further exploration as a promising anti-cancer therapy.展开更多
Interleukin(IL)-22,a member of the IL-10 cytokine family,plays critical roles in tissue repair and host defense.IL-22 binds to its hetereodimeric receptor(R)composed of IL-22R1 and IL-10R2 and activates downstream sig...Interleukin(IL)-22,a member of the IL-10 cytokine family,plays critical roles in tissue repair and host defense.IL-22 binds to its hetereodimeric receptor(R)composed of IL-22R1 and IL-10R2 and activates downstream signaling,including Signal transducer and activator of transcription 3(STAT3)pathways.IL-22 promotes the expression of survival genes in a STAT3-dependent manner.IL-22R1 expression is restricted mainly in epithelial cells while IL-10R2 is ubiquitously expressed in almost all cell types.In the liver,IL-22R1 is expressed in hepatocytes,liver progenitor cells,hepatic stellate cells and liver cancer cells.IL-22 protects the liver in various liver damage models and promotes liver regeneration after liver injury.IL-22 also helps to resolve liver fibrosis by inducing hepatic stellate cell senescence.IL-22 is considered a pro-inflammatory cytokine in viral hepatitis although it does not directly act on immune cells.IL-22 is reported to be involved in the development of liver cancer and in regulating energy metabolism.Studies on IL-22 in liver inflammation,injury and repair will provide valuable information to clarify IL-22 as a potential candidate for treating liver injury and fibrosis.展开更多
[Objectives]To study the effect of total flavonoids extracted from Polygonum perfoliatum L.(TFP)on immune-mediated liver injury induced by bacillus Calmette-Guerin plus lipopolysaccharide(BCG+LPS)in mice,and to explor...[Objectives]To study the effect of total flavonoids extracted from Polygonum perfoliatum L.(TFP)on immune-mediated liver injury induced by bacillus Calmette-Guerin plus lipopolysaccharide(BCG+LPS)in mice,and to explore its action mechanism.[Methods]60 Kunming mice were divided into normal group,model group,control group(bifendate)and TFP low,medium and high dose groups according to random number table method,with 10 mice in each group.On the first day of modeling,mice were injected with 0.2 mL of BCG solution(12.5 mg/mL)through the tail vein,and on the eleventh day,0.2 mL of LPS(37.5μg/mL)were injected into the tail vein to prepare a mouse model of immune-mediated liver injury;from the first day of modeling,the normal group and the model group were administered intragastrically with the corresponding volume of distilled water,and the bifendate group and the TFP high,medium,and low dose groups were administered intragastrically with the corresponding doses once a day for 11 d.After the last time administration,fasting but giving water for 16 h,took blood from eyes,then collected the liver tissue.The levels of alanine transaminase(ALT)and aspartate transaminase(AST)in serum were detected by biochemical method;transforming growth factor-β1(TGF-β1),intercellular adhesion molecule-1(ICAM-1),interleukin-6(IL-6)and interleukin-1β(IL-1β)expression levels in liver tissue were detected by enzyme-linked immunosorbent assay(ELISA);phosphorylated protein tyrosine kinase JAK-2(p-JAK2),phosphorylated signal transducer and activator of transcription 3(p-STAT3)protein expression levels were detected by Western Blot method;the degree of liver tissue lesions was detected by HE staining.[Results]Compared with the model group,the levels of ALT and AST in the serum of mice in each dose group of TFP(high dose 600 mg/kg,medium dose 400 mg/kg,and low dose 200 mg/kg)were reduced,and the activities of T-SOD and GSH-Px were increased;the content or expression ofβ1,ICAM-1,IL-6,IL-1βdecreased,and the expression of p-JAK2 and p-STAT3 pr展开更多
信号转导和转录活化因子3(signal transducers and activators of transcription 3,STAT3)是参与一些细胞因子以及生长因子介导的信号转导的转录因子,在正常细胞内调控生长、增殖、分化以及凋亡等一系列生理活动.已有研究表明,JAK/STAT...信号转导和转录活化因子3(signal transducers and activators of transcription 3,STAT3)是参与一些细胞因子以及生长因子介导的信号转导的转录因子,在正常细胞内调控生长、增殖、分化以及凋亡等一系列生理活动.已有研究表明,JAK/STAT、MAPK、mTOR途径均可激活STAT3,持续的STAT3活化与肿瘤细胞的增殖、抗凋亡、侵袭、转移、血管形成及免疫逃逸密切相关;导致靶向抑制STAT3信号途径的寡核苷酸、小分子抑制剂、肽适配子在抗肿瘤治疗中的应用被广泛地开展.实验表明,它们具有抑制肿瘤的效果.本文重点综述了近几年STAT3在抗肿瘤进程中的功能及其在抗肿瘤治疗中的应用研究进展,并对相关问题进行讨论.展开更多
基金supported by National Natural Science Foundation of China(81370521,81670400,and 91739120)National Key R&D Program of China(2017YFC0211600)+1 种基金Support Project of High-level Teachers in Beijing Municipal Universities in the Period of 13th Five-year Plan(CIT&TCD20190332)The Key Science and Technology Project of Beijing Municipal Institutions(KZ202010025032).
文摘Background:Liver regeneration is a fundamental process for sustained body homeostasis and liver function recovery after injury.Emerging evidence demonstrates that myeloid cells play a critical role in liver regeneration by secreting cytokines and growth factors.Peroxisome proliferator-activated receptorα(PPARα),the target of clinical lipid-lowering fibrate drugs,regulates cell metabolism,proliferation,and survival.However,the role of myeloid PPARαin partial hepatectomy(PHx)-induced liver regeneration remains unknown.Methods:Myeloid-specific PPARa-deficient(Ppara^(Mye−/−))mice and the littermate controls(Ppara^(fl/fl))were subjected to sham or 2/3 PHx to induce liver regeneration.Hepatocyte proliferation and mitosis were assessed by immunohistochemical(IHC)staining for 5-bromo-2'-deoxyuridine(BrdU)and Ki67 as well as hematoxylin and eosin(H&E)staining.Macrophage and neutrophil infiltration into livers were reflected by IHC staining for galectin-3 and myeloperoxidase(MPO)as well as flow cytometry analysis.Macrophage migration ability was evaluated by transwell assay.The mRNA levels for cell cycle or inflammation-related genes were measured by quantitative real-time RT-PCR(qPCR).The protein levels of cell proliferation related protein and phosphorylated signal transducer and activator of transcription 3(STAT3)were detected by Western blotting.Results:Ppara^(Mye−/−)mice showed enhanced hepatocyte proliferation and mitosis at 32 h after PHx compared with Ppara^(fl/fl)mice,which was consistent with increased proliferating cell nuclear antigen(Pcna)mRNA and cyclinD1(CYCD1)protein levels in Ppara^(Mye−/−)mice at 32 h after PHx,indicating an accelerated liver regeneration in Ppara^(Mye−/−)mice.IHC staining showed that macrophages and neutrophils were increased in Ppara^(Mye−/−)liver at 32 h after PHx.Livers of Ppara^(Mye−/−)mice also showed an enhanced infiltration of M1 macrophages at 32 h after PHx.In vitro,Ppara-deficient bone marrow-derived macrophages(BMDMs)exhibited markedly enhanced migra
基金Supported by the Basis of Bethune Medical Research Fund of Jilin Province of China(No.200705114)
文摘Signal transducer and activator of transcription 3（STAT3） is a dual functional transcription factor with the functions of signal transduction and transcription regulation. It is reported that the expression of STAT3 in ovarian cancer is significantly higher and STAT3 can facilitate ovarian cancer growth and metastasis. To clarify the definite effect and molecular mechanism of STAT3 involved in ovarian cancer growth and metastasis, STAT3 expression was significantly downregulated by transfecting ovarian cancer model SK-OV-3 cells with the plasmid vector which express specific RNAi that targets human STAT3. The downregulated STAT3 not only decreased the invasion and migration but also inhibited the proliferation of SK-OV-3 cells. Western blot assay shows that the expression of vascular endothelial growth factor（VEGF） and that of Survivin were reduced in the cells with the plasma vector expressing specific RNAi that targets human STAT3. These results demonstrate that STAT3 involved in the invasion and migration of SK-OV-3 regulates the expression of VEGF and Survivin. In addition, VEGF and Survivin could play an important role in ovarian cancer growth and metastasis.
基金This work was supported by National Natural Science Foundation of China(NOs.81874300,41830535,81991525,and 42176109)Key R&D Program of Shandong Province(NO.2020CXGC010503)+2 种基金Shandong Provincial Natural Science Foundation(Major Basic Research Projects,NO.ZR2019ZD18)the Fundamental Research Funds for the Central Universities(NO.202241008)Taishan Scholars Foundation of Shandong Province,China.
文摘The Janus kinase(JAK)/signal transducer and activator of transcription 3(STAT3)regulates the expression of various critical mediators of cancer and is considered as one of the central communication nodes in cell growth and survival.Marine natural products(MNP)represent great resources for discovery of bioactive lead compounds,especially anti-cancer agents.Through the medium-throughput screening of our in-house MNP library,Pretrichodermamide B,an epidithiodiketopiperazine,was identified as a JAK/STAT3 signaling inhibitor.Further studies identified that Pretrichodermamide B directly binds to STAT3,preventing phosphorylation and thus inhibiting JAK/STAT3 signaling.Moreover,it suppressed cancer cell growth,in vitro,at low micromolar concentrations and demonstrated efficacy in vivo by decreasing tumor growth in a xenograft mouse model.In addition,it was shown that Pretrichodermamide B was able to induce cell cycle arrest and promote cell apoptosis.This study demonstrated that Pretrichodermamide B is a novel STAT3 inhibitor,which should be considered for further exploration as a promising anti-cancer therapy.
基金This work was in supported by the National Natural Science Foundation of China(grant number:81100311,81470879/H0318 to S.Yin)and intramural program of USA National Institute on Alcohol Abuse and Alcoholism(NIAAA),National Institutes of Health(NIH).
文摘Interleukin(IL)-22,a member of the IL-10 cytokine family,plays critical roles in tissue repair and host defense.IL-22 binds to its hetereodimeric receptor(R)composed of IL-22R1 and IL-10R2 and activates downstream signaling,including Signal transducer and activator of transcription 3(STAT3)pathways.IL-22 promotes the expression of survival genes in a STAT3-dependent manner.IL-22R1 expression is restricted mainly in epithelial cells while IL-10R2 is ubiquitously expressed in almost all cell types.In the liver,IL-22R1 is expressed in hepatocytes,liver progenitor cells,hepatic stellate cells and liver cancer cells.IL-22 protects the liver in various liver damage models and promotes liver regeneration after liver injury.IL-22 also helps to resolve liver fibrosis by inducing hepatic stellate cell senescence.IL-22 is considered a pro-inflammatory cytokine in viral hepatitis although it does not directly act on immune cells.IL-22 is reported to be involved in the development of liver cancer and in regulating energy metabolism.Studies on IL-22 in liver inflammation,injury and repair will provide valuable information to clarify IL-22 as a potential candidate for treating liver injury and fibrosis.
基金Natural Science Foundation Project of Guangxi(2017GXNSFAA 198326)。
文摘[Objectives]To study the effect of total flavonoids extracted from Polygonum perfoliatum L.(TFP)on immune-mediated liver injury induced by bacillus Calmette-Guerin plus lipopolysaccharide(BCG+LPS)in mice,and to explore its action mechanism.[Methods]60 Kunming mice were divided into normal group,model group,control group(bifendate)and TFP low,medium and high dose groups according to random number table method,with 10 mice in each group.On the first day of modeling,mice were injected with 0.2 mL of BCG solution(12.5 mg/mL)through the tail vein,and on the eleventh day,0.2 mL of LPS(37.5μg/mL)were injected into the tail vein to prepare a mouse model of immune-mediated liver injury;from the first day of modeling,the normal group and the model group were administered intragastrically with the corresponding volume of distilled water,and the bifendate group and the TFP high,medium,and low dose groups were administered intragastrically with the corresponding doses once a day for 11 d.After the last time administration,fasting but giving water for 16 h,took blood from eyes,then collected the liver tissue.The levels of alanine transaminase(ALT)and aspartate transaminase(AST)in serum were detected by biochemical method;transforming growth factor-β1(TGF-β1),intercellular adhesion molecule-1(ICAM-1),interleukin-6(IL-6)and interleukin-1β(IL-1β)expression levels in liver tissue were detected by enzyme-linked immunosorbent assay(ELISA);phosphorylated protein tyrosine kinase JAK-2(p-JAK2),phosphorylated signal transducer and activator of transcription 3(p-STAT3)protein expression levels were detected by Western Blot method;the degree of liver tissue lesions was detected by HE staining.[Results]Compared with the model group,the levels of ALT and AST in the serum of mice in each dose group of TFP(high dose 600 mg/kg,medium dose 400 mg/kg,and low dose 200 mg/kg)were reduced,and the activities of T-SOD and GSH-Px were increased;the content or expression ofβ1,ICAM-1,IL-6,IL-1βdecreased,and the expression of p-JAK2 and p-STAT3 pr
文摘信号转导和转录活化因子3(signal transducers and activators of transcription 3,STAT3)是参与一些细胞因子以及生长因子介导的信号转导的转录因子,在正常细胞内调控生长、增殖、分化以及凋亡等一系列生理活动.已有研究表明,JAK/STAT、MAPK、mTOR途径均可激活STAT3,持续的STAT3活化与肿瘤细胞的增殖、抗凋亡、侵袭、转移、血管形成及免疫逃逸密切相关;导致靶向抑制STAT3信号途径的寡核苷酸、小分子抑制剂、肽适配子在抗肿瘤治疗中的应用被广泛地开展.实验表明,它们具有抑制肿瘤的效果.本文重点综述了近几年STAT3在抗肿瘤进程中的功能及其在抗肿瘤治疗中的应用研究进展,并对相关问题进行讨论.
