Exploring the mechanism of electroacupuncture at different acupoints on acute colitis rats based on JAK2/STAT3/SOCS1 signaling pathway

Objective:To investigate the mechanism of JAK2/STAT3/SOCS1 signaling pathway in electroacupuncture of different acupoints on acute colitis rats.Methods:36 SPF SD rats were randomly divided into 6 groups,with 6 rats in each group.The rat model of acute colitis was prepared by enema with glacial acetic acid solution.After the model was established,electroacupuncture was given to each acupoint group,with density wave,frequency 2Hz-50 Hz,intensity 2 mA,muscle tremor as the degree 20 min/time,1 time/day,for 3 consecutive days.Observe the general condition of rats;the pathological changes of colonic mucosa in rats were observed by HE method.The contents of serum interleukin-4(IL-4)and interleukin-8(IL-8)were detected by ELISA.Western blot and RT-PCR were used to detect the expression of JAK2,STAT3,SOCS1 protein and mRNA in rat colon tissue.Results:In contrast to the normal group,the overall condition of the model group was worse,the colonic mucosa was severely damaged,even necrotic,and the ulcer surface was obvious.The content of IL-4 in serum was obviously reduced,and the content of IL-8 was obviously go up(P<0.01).The protein content of JAK2,STAT3 and the expression of JAK2,STAT3 mRNA in colon tissue of rats were obviously go up,while the protein content of SOCS1 and the expression of SOCS1 mRNA were obviously reduced(P<0.01).In contrast to the model group,the general condition of rats in each acupoint group was significantly improved,the damage and necrosis of colonic mucosa and ulcer surface were obviously alleviated,the content of IL-4 in serum was obviously go up,and the content of IL-8 was significantly decreased(P<0.01).The protein content of JAK2,STAT3 and the expression of JAK2,STAT3 mRNA in colon tissue of rats were obviously reduced,while the protein content of SOCS1 and the expression of SOCS1 mRNA were obviously go up(P<0.05,P<0.01).Comparison of different acupoint groups,the colonic mucosal injury in the Zusanli group was significantly reduced,the content of serum IL-4 was significantly increased,and the content of IL-8 was significantly decreased(P<0.05,P<0.01).The protein content and mRNA expression of JAK2 and STAT3 in colon tissue were significantly down-regulated,while the protein content and mRNA expression of SOCS1 were significantly go up(P<0.05,P<0.01).Conclusion:Electroacupuncture at each acupoint can improve the damage of colonic mucosa and reduce the inflammatory response.The therapeutic effect of Zusanli(ST36)is better than that of Tianshu(ST25),Dachangshu(BL25)and Shangjuxu(ST37).The mechanism may be related to the regulation of JAK2/STAT3/SOCS1 signaling pathway related proteins and inflammatory cytokines IL-4 and IL-8.

Argatroban promotes recovery of spinal cord injury by inhibiting the PAR1/JAK2/STAT3 signaling pathway

Argatroban is a synthetic thrombin inhibitor approved by U.S.Food and Drug Administration for the treatment of thrombosis.However,whether it plays a role in the repair of spinal cord injury is unknown.In this study,we established a rat model of T10 moderate spinal cord injury using an NYU Impactor ModerⅢand performed intraperitoneal injection of argatroban for 3 consecutive days.Our results showed that argatroban effectively promoted neurological function recovery after spinal cord injury and decreased thrombin expression and activity in the local injured spinal cord.RNA sequencing transcriptomic analysis revealed that the differentially expressed genes in the argatroban-treated group were enriched in the JAK2/STAT3 pathway,which is involved in astrogliosis and glial scar formation.Western blotting and immunofluorescence results showed that argatroban downregulated the expression of the thrombin receptor PAR1 in the injured spinal cord and the JAK2/STAT3 signal pathway.Argatroban also inhibited the activation and proliferation of astrocytes and reduced glial scar formation in the spinal cord.Taken together,these findings suggest that argatroban may inhibit astrogliosis by inhibiting the thrombin-mediated PAR1/JAK2/STAT3 signal pathway,thereby promoting the recovery of neurological function after spinal cord injury.

Oleanolic acid inhibits colon cancer cell stemness and reverses chemoresistance by suppressing JAK2/STAT3 signaling pathway

Background:Oleanolic acid(OA),a pentacyclic triterpenoid exhibiting specific anti-cancer properties and highly effective antioxidant activity,was isolated from traditional Chinese medicinal herbs.Conversely,the OA that impacts colon cancer(CC)cells and its underlying mechanisms remain poorly understood.Methods:The cytotoxic effect of OA alone or OA-5-Fluorouracil(5-FU)combination on normal and CC cells was analyzed by methyl thiazolyl diphenyl-tetrazolium bromide(MTT).Then,the impact of OA on CC cell lines(LoVo and HT-29)proliferation and stemness were measured using colon formation and tumorsphere formation assays.Octamer-binding transcription factor 4(Oct4),Prominin-1(CD133),Nanog,and transcription factor SOX-2(SOX2)are cell stemness-related indicators whose expression was assessed usingfluorescence qPCR assay,Western blotting,and immunohistochemistry.The effect of OA on the proliferative potency of CC cells was evaluated using an in vivo model.Results:The stem-like characteristics and clone production of colon cancer cells were markedly reduced by OA alone or in combination with OA-5-FU.Moreover,OA increases the susceptibility of CC cells to 5-FU by blocking the cell stemness-related markers(CD133,Nanog,SOX2,and Oct4)expression levels both in vitro and in vivo,as well as by inactivating the activator of transcription 3(STAT3 signaling)and Janus kinase 2/signal transducer(JAK2).Conclusion:Thesefindings imply that oleanolic acid,both in vitro and in vivo,suppresses the JAK2/STAT3 pathway,which in turn reverses chemoresistance and decreases colon cancer cell stemness.Therefore,by reducing the recommended amount of 5-FU,this strategy may improve chemotherapeutic effectiveness and minimize undesired side effects.

Effects of plumbagin on migration and invasion of human hepatoma cell line via JAK2/STAT3 signaling pathway

Objective:To study the effect of plumbagin(PL)on the migration and invasion of human hepatocellular carcinoma(HCC)cells and its possible mechanism.Methods:The cell counting kit(CCK-8)was used to detect the effects of different concentrations of plumbagin on the proliferation of human hepatocellular carcinoma Huh-7 and LM3 cells.The effect of plumbagin on the migration ability of Huh-7 and LM3 cells was detected by scratch test and Transwell migration test,and the effect of on the invasion ability of Huh-7 and LM3 cells was detected by Transwell invasion test.Western Blot was used to detect the expression of E-cadherin,N-cadherin,matrix metalloproteinase-2 and related proteins in JAK2/STAT3 signaling pathway in Huh-7 and LM3 cells.Results:Plumbagin could inhibit the proliferation of Huh-7 and LM3 cells in a time-and concentration-dependent manner.Plumbagin inhibited the migration and invasion of Huh-7 and LM3 cells in a concentration dependent manner,and it can down-regulate the expression of N-cadherin and MMP-2 protein,up-regulate the expression of E-cadherin protein,and inhibit the activation of JAK2/STAT3 signaling pathway.Conclusion:Plumbagin can inhibit the migration and invasion of human hepatocellular carcinoma Huh-7 and LM3 cells,and the molecular mechanism of this process may be related to the inhibition of JAK2/STAT3 signaling pathway activation.

To explore the mechanism of Dahuang Lingxian Formula in relieving inflammatory response of bile duct cells based on IL-6/JAK/STAT3 signaling pathway

Objective:To explore the mechanism of action of Dahuang Lingxian Formula in alleviating the inflammatory response of bile duct cells in LPS-induced intrahepatic bile duct inflammation model rats based on IL-6/JAK/STAT3 signaling pathway.Methods:Fifty SD rats were randomly divided into five groups,blank group,model group,choling tablets(0.5 g/kg),and low and high concentration groups(2.4 g/kg and 4.8 g/kg)of Dahuang Lingxian Formula,ten rats in each group.Except for the blank group,the rats in each group were injected with 1.25 mg/kg LPS at the common bile duct at one time to construct an animal model of intrahepatic bile duct infection.After gavage on day 8,liver tissues were taken from rats at the hepatic hilum,and the histopathological changes of the hepatic hilum and biliary tree were observed by HE staining.The expression levels of serum glutamic alanine transaminase(ALT),glutamic oxalacetic transaminase(AST),malondialdehyde(MDA)and superoxide dismutase(SOD)were measured by biochemical method.The expression levels of interleukin 6(IL-6),Janus protein tyrosine kinase 2(JAK2),signal transducer and activator of transcription 3(STAT3)in rat serum were measured by enzyme-linked immunosorbent assay(ELISA).Protein immunoblotting(WB)and real-time fluorescence quantitative PCR(RT-qPCR)were used to detect the expression levels of IL-6,JAK2,STAT3 protein and mRNA in biliary tree tissues.Results:①Compared with the blank group,the structures such as interlobular bile ducts in the hepatic sinusoids and portal duct area of the model rats were destroyed,and inflammatory cells infiltrated around them.The expression of ALT,AST,MDA,IL-6,JAK2 and STAT3 in the serum increased significantly,the expression level of SOD decreased,and the expression levels of IL-6,JAK2 and STAT3 proteins and mRNA increased.②Compared with the model group,the degree of liver pathological damage in rats in the Chiling Ning tablet group and the low and high concentration groups of Dahuang Lingxian Formula were improved,which could significantly reduce the expression levels of ALT,AST,MDA,IL-6,JAK2,STAT3 and up-regulate SOD in serum,and down-regulate the expression of IL-6,JAK2,STAT3 protein and mRNA,with the best effect in the high concentration group of Dahuang Lingxian Formula.③Compared with the choling tablet group,the rats in the low and high concentration groups of Dahuang Lingxian Formula tended to normalize the degree of liver pathological damage,without obvious inflammatory cell infiltration,and the expression levels of ALT,AST,MDA,IL-6,JAK2,STAT3 and the expression levels of IL-6,JAK2,STAT3 protein and mRNA in serum were reduced,and the expression levels of SOD were increased,with the best effect of Dahuang Lingxian Formula The treatment effect was best in the high concentration group.Conclusion:The mechanism may be related to the down-regulation of IL-6/JAK/STAT3 signaling pathway activation,and the best therapeutic effect was achieved by the high concentration group of Dahuang Lingxian Formula.

Elevated retinol binding protein 4 levels are associated with atherosclerosis in diabetic rats via JAK2/STAT3 signaling pathway

BACKGROUND Atherosclerosis is a major cause of mortality worldwide and is driven by multiple risk factors,including diabetes,which results in an increased atherosclerotic burden,but the precise mechanisms for the occurrence and development of diabetic atheroscerosis have not been fully elucidated.AIM To summarize the potential role of retinol binding protein 4(RBP4) in the pathogenesis of diabetic atheroscerosis,particularly in relation to the RBP4-Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)signaling pathway.METHODS Male Wistar rats were randomly divided into three groups,including a control group(NC group),diabetic rat group(DM group),and diabetic atherosclerotic rat group(DA group).The contents of total cholesterol(TC), high-density lipoprotein cholesterol(HDL-c), triglycerides(TG), low-density lipoprotein cholesterol(LDLc), fasting insulin(FINS),fasting plasma glucose,and hemoglobin A1 c(HbA1 c)were measured.Moreover,the adipose and serum levels of RBP4,along with the expression levels of JAK2, phosphorylated JAK2(p-JAK2), STAT3,phosphorylated STAT3(p-STAT3), B-cell lymphoma-2(Bcl-2), and Cyclin D1 in aortic tissues were also measured.Besides,homeostasis model assessment of insulin resistance(HOMA-IR) and atherogenic indexes(AI) were calculated.RESULTS Compared with the NC and DM groups,the levels LDL-c,TG,TC,FINS,HOMAIR,RBP4,and AI were upregulated,whereas that of HDL-c was downregulated in the DA group(P <0.05);the mRNA levels of JAK2,STAT3,Cyclin D1,and Bcl-2 in the DA group were significantly increased compared with the NC group and the DM group;P-JAK2,p-JAK2/JAK2 ratio,p-STAT3,p-STAT3/STAT3 ratio,Cyclin D1,and Bcl-2 at protein levels were significantly upregulated in the DA group compared with the NC group and DM group.In addition,as shown by Pearson analysis,serum RBP4 had a positive correlation with TG,TC,LDL-c,FINS,HbA1 C,p-JAK2,p-STAT3,Bcl-2,Cyclin D1,AI,and HOMA-IR but a negative correlation with HDL-c.In addition,multivariable logistic regression analysis showed that serum RBP4,p-JAK2,p-STAT3,and LDL-c were predictors of the presence of diabetic atherosclerosis.CONCLUSION RBP4 could be involved in the initiation or progression of diabetic atherosclerosis by regulating the JAK2/STAT3 signaling pathway.

Hepatocellular carcinoma-derived exosomal miRNA-761 regulates the tumor microenvironment by targeting the SOCS2/JAK2/STAT3 pathway

BACKGROUND:Exosomes and exosomal microRNAs have been implicated in tumor occurrence and metastasis.Our previous study showed that microRNA-761(miR-761)is overexpressed in hepatocellular carcinoma(HCC)tissues and that its inhibition affects mitochondrial function and inhibits HCC metastasis.The mechanism by which exosomal miR-761 modulates the tumor microenvironment has not been elucidated.METHODS:Exosomal miR-761 was detected in six cell lines.Cell counting kit-8(CCK-8)and transwell migration assays were performed to determine the function of exosomal miR-761 in HCC cells.The luciferase reporter assay was used to analyze miR-761 target genes in normal fi broblasts(NFs).The inhibitors AZD1480 and C188-9 were employed to determine the role of the Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)signaling pathway in the transformation of cancer-associated fi broblasts(CAFs).RESULTS:In this study,we characterized the mechanism by which miR-761 reprogrammed the tumor microenvironment.We found that HCC-derived exosomal miR-761 was taken up by NFs.Moreover,HCC exosomes aff ected the tumor microenvironment by activating NFs via suppressor of cytokine signaling 2(SOCS2)and the JAK2/STAT3 signaling pathway.CONCLUSIONS:These results demonstrated that exosomal miR-761 modulated the tumor microenvironment via SOCS2/JAK2/STAT3 pathway-dependent activation of CAFs.Our fi ndings may inspire new strategies for HCC prevention and therapy.

3-epi-bufotalin suppresses the proliferation in colorectal cancer cells through the inhibition of the JAK1/STAT3 signaling pathway

Traditional Chinese medicine(TCM)has been increasingly employed in the last decades in China for both preventing and treating a variety of cancers.3-epi-bufotalin is an active ingredient of TCM“Chanpi”with anti-tumor potential.However,the effect and mechanism of 3-epi-bufotalin on colorectal cancers were not well disclosed.The present study demonstrated that 3-epi-bufotalin could reduce viability,trigger apoptosis,and block the cell cycle at the G2/M stage in colorectal cancer cell lines HT29,RKO,and COLO205 in vitro.Moreover,3-epi-bufotalin inhibited the JAK1/STAT3 signaling pathway.These results indicated the anti-proliferation ability of 3-epi-bufotalin in colorectal cancer cells.

Value of spiral CT perfusion parameters for evaluating acute pancreatitis and their correlation with inflammatory factor and JAK2/STAT3 signaling pathway

Objective: To study the value of spiral CT perfusion parameters for evaluating acute pancreatitis and their correlation with inflammatory factor and JAK2/STAT3 signaling pathway. Methods: Patients with acute pancreatitis and patients with pancreatic trauma who underwent surgical resection in Liaocheng Dongchangfu People's Hospital between May 2014 and March 2017 were selected and enrolled in the AP group and the control group of the research respectively;spiral CT perfusion scanning was conducted before surgery to measure the blood flow (BF), blood volume (BV), and mean transit time (MTT), and the serum was collected to determine the contents of inflammatory factors;pancreatitis tissue and normal pancreatic tissue were collected after surgical resection to determine the expression of JAK2/STAT3 signal molecules. Results: pancreatic tissue BF and BV levels of AP group were significantly lower than those of control group while MTT level was not different from that of control group;CRP, PCT, HMGB-1, Ghrelin and sTREM-1 contents in serum as well as JAK2, STAT3, Bcl-2 and Bcl-xL mRNA expression in pancreatic tissue of AP group were significantly higher than those of control group and negatively correlated with BF and BV levels in pancreatic tissue. Conclusion: Spiral CT perfusion parameters BF and BV can reflect the microcirculatory disorder of acute pancreatitis and are associated with the increased secretion of inflammatory factors and the activation of JAK2/STAT3 signaling pathway in the course of disease.

复方鱼腥草对糖尿病小鼠肾损伤和JAK/STAT-SOCS-1负反馈调节研究

目的研究复方鱼腥草3种提取部位及其完整成分对db/db小鼠肾损害的保护作用,通过研究各提取物对JAK2/STAT3通路及其下游蛋白的影响探讨复方鱼腥草防治糖尿病肾病的可能机制。方法 1、提取复方鱼腥草水提物、醇提物、挥发油成分,并将3种成分按照所得质量比配制得到复方鱼腥草完整成分。2、选取8只db/m小鼠为正常组;将56只db/db小鼠分为模型组、盐酸二甲双胍组、AG490组、复方鱼腥草水提物组、复方鱼腥草醇提物组、复方鱼腥草挥发油组以及复方鱼腥草完整成分组,每组8只,给药8周,酶联免疫试剂盒法检测血浆转化生长因子-β1(TGF-β1)、纤连蛋白(FN)、胰高血糖素样肽-1(GLP-1)、抑胃肽(GIP)水平,HE染色观察小鼠肾脏病理变化。3、以RT-PCR法检测各组小鼠肾组织中的JAK2 mRNA、STAT3mRNA、SOCS-1 mRNA表达的变化情况;以Western Blot法检测肾组织中的JAK2、p-JAK2、STAT3、pSTAT3、SOCS-1、c-fos及c-jun蛋白表达变化,运用免疫荧光法检测肾组织c-fos、c-jun蛋白的表达。结果给药8周后,与正常组比较,模型组血浆中TGF-β1、FN、GIP水平升高(P <0.05),GLP-1水平下降(P <0.05);与模型组比较,治疗组小鼠血浆中TGF-β1、FN、GIP、GLP-1水平及肾组织病理改变均有所改善。模型组小鼠肾组织p-JAK2、p-STAT3蛋白表达及JAK2、STAT3 mRNA表达均比正常组增高(P <0.05);与模型组相比,各给药组小鼠肾组织p-JAK2,p-STAT3蛋白表达均有降低,醇提物组、挥发油组及完整成分组小鼠肾组织SOCS-1蛋白显著升高(P <0.05);各给药组的JAK2、STAT3基因表达变化不显著(P> 0.05)。AG490组及完整成分组的c-fos、c-jun在肾小管及肾间质的表达均有不同程度下降(P <0.05)。结论复方鱼腥草对糖尿病肾损伤具有改善作用,其保护肾脏的作用可能与调节GLP-1、GIP水平,降低FN、TGF-β1的分泌,减少ECM聚积,维持肾脏结构、功能的完整性有关。其改善糖尿病肾损伤的分子机制可能通过SOCS负反馈调节JAK/STAT信号转导通路相关基因及蛋白表达,从而抑制降低下游原癌基因c-fos、c-jun的表达,减少炎症因子的活化有关。

Differential regulation of JAK/STAT-signaling in patients with ulcerative colitis and Crohn’s disease

In 2018,the pan-Janus kinase(JAK)inhibitor tofacitinib was launched for the treatment of ulcerative colitis(UC).Although tofacitinib has proven efficacious in patients with active UC,it failed in patients with Crohn’s disease(CD).This finding strongly hints at a different contribution of JAK signaling in both entities.Here,we review the current knowledge on the interplay between the JAK/signal transducer and activator of transcription(STAT)pathway and inflammatory bowel diseases(IBD).In particular,we provide a detailed overview of the differences and similarities of JAK/STAT-signaling in UC and CD,highlight the impact of the JAK/STAT pathway in experimental colitis models and summarize the published evidence on JAK/STAT-signaling in immune cells of IBD as well as the genetic association between the JAK/STAT pathway and IBD.Finally,we describe novel treatment strategies targeting JAK/STAT inhibition in UC and CD and comment on the limitations and challenges of the new drug class.

JAK/STAT signaling regulates tissue outgrowth and male germline stem cell fate in Drosophila

In multicellular organisms, biological activities are regulated by cell signaling. The various signal transduction path- ways regulate cell fate, proliferation, migration, and polarity. Miscoordination of the communicative signals will lead to disasters like cancer and other fatal diseases. The JAK/STAT signal transduction pathway is one of the pathways, which was first identified in vertebrates and is highly conserved throughout evolution. Studying the JAK/STAT signal transduc- tion pathway in Drosophila provides an excellent opportunity to understand the molecular mechanism of the cell regu- lation during development and tumor formation. In this review, we discuss the general overview of JAK/STAT signaling in Drosophila with respect to its functions in the eye development and stem cell fate determination.

Research progress on signaling pathways in cirrhotic portal hypertension

Portal hypertension(PHT) is an important consequence of liver cirrhosis, which can lead to complications that adversely affect a patient's quality of life and survival, such as upper gastrointestinal bleeding, ascites, and portosystemic encephalopathy. In recent years, advances in molecular biology have led to major discoveries in the pathological processes of PHT, including the signaling pathways that may be involved: PI3 K-AKT-mTOR, RhoA/Rho-kinase, JAK2/STAT3, and farnesoid X receptor. However, the pathogenesis of PHT is complex and there are numerous pathways involved. Therefore, the targeting of signaling pathways for medical management is lagging. This article summarizes the progress that has been made in understanding the signaling pathways in PHT, and provides ideas for treatment of the disorder.

HBP1 inhibits chicken preadipocyte differentiation by activating the STAT3 signaling via directly enhancing JAK2 expression

Obesity presents a serious threat to human health and broiler performance.The expansion of adipose tissue is mainly regulated by the differentiation of preadipocytes.The differentiation of preadipocytes is a complex biological process regulated by a variety of transcription factors and signaling pathways.Previous studies have shown that the transcription factor HMG-box protein 1(HBP1)can regulate the differentiation of mouse 3T3-L1 preadipocytes by activating the Wnt/β-catenin signaling pathway.However,it is unclear whether HBP1 involved in chicken preadipocyte differentiation and which signaling pathways it regulates.The aim of the current study was to explore the biological function and molecular regulatory mechanism of HBP1 in the differentiation of chicken preadipocytes.The expression patterns of chicken HBP1 in abdominal adipose tissue and during preadipocyte differentiation were analyzed by RT-qPCR and Western blot.The preadipocyte stably overexpressing HBP1 or knockout HBP1 and their control cell line were used to analyze the effect of HBP1 on preadipocyte differentiation by oil red O staining,RT-qPCR and Western blot.Cignal 45-Pathway Reporter Array was used to screen the signal pathways that HBP1 regulates in the differentiation of chicken preadipocytes.Chemical inhibitor and siRNA for signal transducer and activator of transcription 3(STAT3)were used to analyze the effect of STAT3 on preadipocyte differentiation.The preadipocyte stably overexpressing HBP1 was transfected by the siRNA of STAT3 or treated with a chemical inhibitor of STAT3 for the rescue experiment.The results of gene expression analysis showed that the expression of HBP1 was related to abdominal fat deposition and preadipocyte differentiation in chickens.The results of function gain and loss experiments indicated that overexpression/knockout of HBP1 in chicken preadipocytes could inhibit/promote(P<0.05)lipid droplet deposition and the expression of adipogenesis-related genes.Mechanismlly,HBP1 activates(P<0.05)the signal transducer and activator of transcription 3(STAT3)signaling pathway by targeting janus kinase 2(JAK2)transcription.The results of functional rescue experiments indicated that STAT3 signaling mediated the regulation of HBP1 on chicken preadipocyte differentiation.In conclusion,HBP1 inhibits chicken preadipocyte differentiation by activating the STAT3 signaling pathway via directly enhancing JAK2 expression.Our findings provided new insights for further analysis of the molecular genetic basis of chicken adipose tissue growth and development.

基于JAK/STAT信号通路的中药治疗慢性萎缩性胃炎药理机制研究进展

现关于中医药干预慢性萎缩性胃炎(chronic atrophic gastritis,CAG)的临床研究和基础实验研究已成为消化系统疾病中的研究热点。Janus蛋白酪氨酸激酶(Janus protein tyrosine kinase,JAK)/信号转导子与激活子(signal transducer and activator of transcription,STAT)信号通路的状态与消化道疾病的发生与进展十分密切。诸多研究表明中药可通过多种机制调控该信号通路干预CAG的进展,大致可分为以下几个方面:通过抑制JAK2/STAT3、核转录因子-κB/STAT1通路激活或促使白介素-4(interleukin-4,IL-4)/STAT6激活达到干预CAG的目的;同时降低IL-6、IL-1β等相关炎症因子表达,不仅可抑制相关通路激活,亦可起到减轻胃黏膜炎症的作用;再者上调抑癌基因p21、下调原癌基因表达防止受损的胃黏膜进一步恶化;最后还可调节生存素、B淋巴细胞瘤2家族调控细胞凋亡/增殖平衡机制逆转胃黏膜萎缩及肠化生。

Antiproliferation Effects of Curcumin on the STAT5 Signaling Parthway in K562 Cells

OBJECTIVE Curcumin is the major component of the spice turmeric and the yellow pigment in curry powder. Many studies have shown that curcumin （diferuloylmethane） has significant antiproliferative and apoptotic effects in cancer cells by several mechanisms. Signal transducers and activators of transcription （STAT） proteins are critical in mediating a response in hematopoietic cells. This study was designed to investigate whether curcumin is associated with proteins involved in signal transduction and activation of transcription （STAT） and to investigate the expression of signal transducers and activators of transcription and the significance of the STAT5 signaling pathway of by treating k562 cells and cells from CML patients with curcumin. METHODS The study was divided into the following groups： normal control cells （human bone marrow cells）, untreated K562 cells, curcumin treated K562 cells, IFN-γ treated K562 cells, curcumin plus IFN-γ treated K562 cells, and CML patient cells with and without curcumin treatment. Cell proliferation was measured by the MTT assay. The expression of STAT5 mRNA was determined by RT-PCR. The expression of the STAT5 protein was assayed by Western-blotting and the expression of STAT5 in K562 cells was examined under confocal laser-scanning microscopy. The expression of STAT5 mRNA of K562 cells was determined with in situ hybridization. EMSA was used to assess the change in binding of STAT5 with DNA in CML patient cells. RESULTS The proliferation of the K562 cells and CML primary cells was decreased in the curcumin-treated group and/or IFN-γ group. The expression of STAT5 mRNA and protein were decreased the curcumin-treated group as compared with the K562 untreated group （P〈0.01）. STAT5 mRNA and protein expression was decreased in the IFN-γ group compared to the untreated K562 group （P〈0.01）. Combined use of curcumin with IFN-γ inhibited the proliferation of K562 cells and decreased the expression of STAT5 mRNA and protein of the K562 cells. For the CML patient cells, the OD value of STAT5-DNA binding in the curcumin treated cells was less than that compared to untreated cells. CONCLUSION The antiproliferation effects of curcumin may partly be mediated through signal transduction and activation of transcription and may involve the STAT5 signaling pathway.

SOCS-3在肝脏疾病中的作用研究进展

细胞因子信号转导抑制蛋白-3(suppressor of cytokine signaling,SOCS-3)是一种细胞因子信号转导阻抑蛋白,参与体内多种信号转导通路的调节。研究发现,SOCS-3与肝纤维化、病毒性肝炎和肝肿瘤的发生发展均存在一定的关系,并且干扰素的抗病毒疗效与SOCS-3的遗传学表达改变密切相关。本综述将对SOCS-3的结构、分子功能及近年来在肝疾病中的相关研究进行简要总结。

SOCS的免疫调节机制及其在慢性肝病中的作用

细胞因子转导抑制因子(SOCS)是细胞外信号引起的信号转导过程中关键的负调控因子,SOCS家族通过一系列机制负调控Janus激酶/信号转导子和转录激活子(JAK/STAT)信号通路,从而调节靶基因的表达而发挥生物学作用,在免疫相关疾病、肿瘤疾病中扮演重要角色。目前越来越多的研究证明,在各种慢性肝病(CLD),包括慢性病毒性肝炎、非酒精性脂肪肝、肝纤维化、肝癌等疾病中存在SOCS蛋白表达异常,研究SOCS在慢性肝病中的作用机制,可能为相关肝病的治疗提供新的策略。本文简要介绍了SOCS的免疫调节机制,重点阐述了其在各种慢性肝病中的作用。

Influence of overexpression of SOCS2 on cells of DN rat

Objective: To explore the influence and mechanism of overexpression of SOCS2 on diabetic nephropathy(DN) rats and cells. Methods: STZ was used to induce male SD rats and SOCS2 was injected into left renal vein. Rats were divided into DN group, DN-Ad-null group and DNAd-SOCS2 group. Glucose with high and normal concentration was used to culture HBZY-1 cells and then transfect Ad-SOCS2. HG group, HG-Ad-null group, HG-Ad-SOCS2 group, CG group, CG-Ad-null group, and CG-Ad-SOCS2 group were created. The expression of inflammatory cytokines(MCP-1, TNF-α and IL-6) in kidney tissue of rats, fibrosis related protein(FN, Collagen Ⅳ and TGF-β) in kidney tissue and cells of rats, and JAK/STAT signaling pathway related proteins(p-JAK2 and p-STAT3) were tested by western blot. ELISA was used to test the expression of inflammatory cytokines(TNF-α and IL-6) in cells. Results: The expression of inflammatory cytokines in DN rats(MCP-1, TNF-α and IL-6) and cell(TNF-α and IL-6) were increased(P<0.01) significantly. However, SOCS2 could decrease the overexpression of mediated inflammatory cytokines in DN animal models and cell models(P<0.01). The expression of fibrosis related protein in DN rats and cells increased while SOCS2 decreased the overexpression of mediated fibrosis related protein in DN model rats and cells(P<0.01). The expression of JAK/STAT pathway related protein in both DN rats and cells increased and the JAK/STAT signaling pathway was activated. Yet, SOCS2 obviously suppressed the expression of the JAK/STAT signaling pathway as well as the related proteins(p-JAK2 and p-STAT3) in both DN rats and cells. Conclusions: The overexpression of SOCS2 can decrease the expression of inflammatory cytokines and fibrosis related proteins in DN rats and cells, and meanwhile suppress the activation of JAK/STAT signaling pathway mediated by DN.

3C^(pro)of FMDV inhibits type II interferon-stimulated JAK-STAT signaling pathway by blocking STAT1 nuclear translocation

Foot-and-mouth disease virus(FMDV)has developed various strategies to antagonize the host innate immunity.FMDV Lpro and 3Cpro interfere with type I IFNs through different mechanisms.The structural protein VP3 of FMDV degrades Janus kinase 1 to suppress IFN-γsignaling transduction.Whether non-structural proteins of FMDV are involved in restraining type II IFN signaling pathways is unknown.In this study,it was shown that FMDV replication was resistant to IFN-γtreatment after the infection was established and FMDV inhibited type II IFN induced expression of IFN-γ-stimulated genes(ISGs).We also showed for the first time that FMDV non-structural protein 3C antagonized IFN-γ-stimulated JAK-STAT signaling pathway by blocking STAT1 nuclear translocation.3C^(pro)expression significantly reduced the ISGs transcript levels and palindromic gamma-activated sequences(GAS)promoter activity,without affecting the protein level,tyrosine phosphorylation,and homodimerization of STAT1.Finally,we provided evidence that 3C protease activity played an essential role in degrading KPNA1 and thus inhibited ISGs mRNA and GAS promoter activities.Our results reveal a novel mechanism by which an FMDV non-structural protein antagonizes host type II IFN signaling.