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.

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.

Morroniside ameliorates lipopolysaccharide-induced inflammatory damage in iris pigment epithelial cells through inhibition of TLR4/JAK2/STAT3 pathway

AIM:To investigate the effect of morroniside(Mor)on lipopolysaccharide(LPS)-treated iris pigment epithelial cells(IPE).METHODS:IPE cells were induced by LPS and treated with Mor.Cell proliferation was detected by cell counting kit(CCK)-8,apoptosis was detected by flow cytometry,the levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,and IL-8 were measured by enzyme-linked immunosorbent assay(ELISA)kits,and the protein expression of TLR4,JAK2,p-JAK2,STAT3,and p-STAT3 was analyzed by Western blotting.In addition,overexpression of TLR4 and Mor treatment of LPS-stimulated IPE cells were also tested for the above indices.RESULTS:Mor effectively promoted the proliferation and inhibited the apoptosis of LPS-treated IPE cells.In addition,Mor significantly reduced the levels of TNF-α,IL-6,and IL-8 and significantly inhibited the expression of TLR4,p-JAK2,and p-STAT3 in LPS-treated IPE cells.The effect of Mor on LPS-treated IPE cells was markedly attenuated after overexpression of TLR4.CONCLUSION:These findings suggest that Mor may ameliorate LPS-induced inflammatory damage and apoptosis in IPE through inhibition of TLR4/JAK2/STAT3 pathway.

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.

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.

Inhibition of cerebral ischemia/reperfusion injuryinduced apoptosis:nicotiflorin and JAK2/STAT3 pathway

Nicotiflorin is a flavonoid extracted from Carthamus tinctorius.Previous studies have shown its cerebral protective effect,but the mechanism is undefined.In this study,we aimed to determine whether nicotiflorin protects against cerebral ischemia/reperfusion injury-induced apoptosis through the JAK2/STAT3 pathway.The cerebral ischemia/reperfusion injury model was established by middle cerebral artery occlusion/reperfusion.Nicotiflorin（10 mg/kg） was administered by tail vein injection.Cell apoptosis in the ischemic cerebral cortex was examined by hematoxylin-eosin staining and terminal deoxynucleotidyl transferase d UTP nick end labeling assay.Bcl-2 and Bax expression levels in ischemic cerebral cortex were examined by immunohistochemial staining.Additionally,p-JAK2,p-STAT3,Bcl-2,Bax,and caspase-3 levels in ischemic cerebral cortex were examined by western blot assay.Nicotiflorin altered the shape and structure of injured neurons,decreased the number of apoptotic cells,down-regulates expression of p-JAK2,p-STAT3,caspase-3,and Bax,decreased Bax immunoredactivity,and increased Bcl-2 protein expression and immunoreactivity.These results suggest that nicotiflorin protects against cerebral ischemia/reperfusion injury-induced apoptosis via the JAK2/STAT3 pathway.

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.

The Influence of Gastrodin on Expression of IL-10, STAT3 and JAK2 in Epileptic Rats’ Hippocampus

Objective: To explore the influence of gastrodin on IL-10, JAK2 and STAT3 in hippocampus of epileptic rats induced by pentylenetetrazol and the role of the IL-10 pathway in epilepsy. Methods: 50 adult male Wistar rats were randomly divided into 5 groups: normal control group (NC Group), epilepsy model group (EP Group), low doses of gastrodin + EP Group (GE1 Group), medium doses of gastrodin + EP Group (GE2 Group), high doses of gastrodin + EP Group (GE3 Group). EP group and GE Groups were injected subthreshold doses of pentylenetetrazole (PTZ) by intraperitoneal once a day until reaching the ignited standards. GE groups were respectively injected 4, 6, 8 mg/kg gastrodin by intraperitoneal. All groups were administered for 28 consecutive days. The behavioral changes of the rats were observed and recorded daily 1 hour after the injection. mRNAs of IL-10, STAT3 and JAK2 in hippocampus were measured by RT-qPCR, and proteins by Western blot. Results: Compared GE2 group with EP group, the incubation of seizure was significantly prolonged (P Conclusions: Gastrodin can increase the expression of IL-10, and reduce the expression of STAT3 and JAK2, which may play an antiepileptic effect through regulating JAK2/STAT3 signaling pathways by IL-10.

Blocking the JAK2/STAT3 and ERK pathways suppresses the proliferation of gastrointestinal cancers by inducing apoptosis

Dysregulated crosstalk between different signaling pathways contributes to tumor development,including resistance to cancer therapy.In the present study,we found that the mitogen-activated extracellular signal-regulated kinase(MEK)inhibitor trametinib failed to suppress the proliferation of PANC-1 and MGC803 cells by activating the Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)signaling pathway,while the JAK2 inhibitor fedratinib failed to inhibit the growth of the PANC-1 cells upon stimulation of extracellular signal-regulated kinase(ERK)signaling.In particular,the most prominent enhancement of the anti-proliferative effect resulted from the concurrent blockage of the JAK2/STAT3 and ERK signaling pathways.Furthermore,the combination of the two inhibitors resulted in a reduced tumor burden in mice.Our evidence suggests novel crosstalk between JAK2/STAT3 and ERK signaling in gastric cancer(GC)and pancreatic ductal adenocarcinoma(PDAC)cells and provides a therapeutic strategy to overcome potential resistance in gastrointestinal cancer.

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.

Scutellarin protects human cardiac microvascular endothelial cells with hypoxia-reoxygenation injury via JAK2/STAT3 signal pathway

Objective: To investigate the antagonistic cell injury effect and molecular mechanism of scutellarin(SCU)in hypoxia reoxygenation(HR) treated human cardiac microvascular endothelial cells(HCMECs).Methods: The method of 12 h hypoxia following by 12 h reoxygenation was used to culture HCMECs in vitro to built cell injury model. The groups were divided into control group, model(HR) group, and HR + SCU(0.1 μmol/L, 1 μmol/L, and 10 μmol/L) group. The cell viability was determined by MTT, and oxidative stress was detected by malondialdehyde(MDA) levels by biochemical assay kit. Protein expression of JAK2/p-JAK2 and STAT3/p-STAT3 were evaluated by Western blot.Results: The results of MTT and MDA showed that HR decreased the cell viability(P < 0.05) and increased MDA level significantly(P < 0.05), SCU played a contrary role in these processes. Western blot analysis indicates that, the expression of JAK2 and p-JAK2, STAT3, and p-STAT3 were increased in model group when compared with control group(P < 0.05); Compared with model group, their expression were reduced by SCU(P < 0.05).Conclusion: SCU took a protective effect on HR-treated HCMECs, and the molecular mechanism may be associated with the inhibition of JAK2/STAT3 signal transduction pathway.

Effect of electroacupuncture on JAK2/STAT3 pathway in synovial tissues of rats with rheumatoid arthritis

Objective: To observe the effect of electroacupuncture (EA) on Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway in knee joint synovial tissues of rats with rheumatoid arthritis (RA) and to explore the action mechanism of EA on RA. Methods: Twelve of the 48 SPF male Sprague-Dawley (SD) rats were assigned to a normal group by the random number table method. The remaining 36 rats were subjected to RA model preparation by intradermal injection of the Freund's complete adjuvant into the right hind foot pad of each rat under sterile conditions. After the model was successfully prepared, rats were then divided into a model group, a drug group and an EA group according to a random number table method (n=12). Rats in the drug group were treated with 2 mL aqueous solution of tripterygium glycosides [8.1 mg/(kg?bw)];rats in the EA group were treated with EA at bilateral Yanglingquan (GB 34) and Zusanli (ST 36), for 30 min each time;rats in the normal group and the model group were placed in a special rat fixation tank for 30 min each time, and received the same dose of normal saline as those in the drug group. Rats in all groups received intervention once a day for 4 weeks. Diameter of rat ankle joint and rat arthritis index were measured before and after the intervention. At the end of the experiment, the expressions of phospho-JAK2 and phospho-STAT3 were determined by immunohistochemistry. Quantitative real-time polymerase chain reaction (RT-qPCR) was used to detect JAK2 and STAT3 mRNAs expressions. Results: After the model was produced, the arthritis index >2 was considered successful in model preparation. Compared with the model group, the ankle joint diameters and arthritis indexes of rats in the drug group and the EA group were significantly lower (all P<0.01);immunohistochemical staining cells with phospho-JAK2 and phospho-STAT3 were significantly decreased (all P<0.01);the expression levels of JAK2 and STAT3 mRNAs were decreased with statistical differences (all P<0.01). There were no significant differences between the EA group and the drug group (all P>0.05). Conclusion: EA can alleviate the inflammatory response of RA rats, improve their pathological conditions, reduce the expressions of phospho-JAK2 and phospho-STAT3 in the synovial tissue of knee joint, and decrease the expressions of JAK2 and STAT3 mRNAs. The therapeutic effect of EA is comparable to that of the tripterygium glycosides. The mechanism of EA treatment may be related to the inactivation of the JAK2/STAT3 pathway.

The spirocyclopiperazinium salt compound LXM-15 alleviates chronic inflammatory and neuropathic pain in mice and rats

In the present study,we aimed to evaluate the effect of the spirocyclopiperazinium salt compound LXM-15 on chronic inflammatory pain and chronic neuropathic pain induced by complete Freund’s adjuvant(CFA)or chronic constriction injury(CCI)in mice and rats.The results showed that administration with LXM-15 significantly reduced paw edema and ankle swelling and increased the mechanical withdrawal threshold and paw withdrawal latency after CFA injection in mice.LXM-15 significantly alleviated the mechanical allodynia and thermal hyperalgesia in CCI rats.The effect was abolished by pretreatment with hexamethonium(a peripheral nAChR antagonist)or methyllycaconitine citrate(anα7 nAChR antagonist).Furthermore,LXM-15 significantly inhibited the phosphorylation of JAK2 and STAT3,and suppressed the expressions of TNF-αand c-fos in dorsal root ganglia of CCI rats.Collectively,we reported that LXM-15 relieved chronic inflammatory pain in CFA mice and chronic neuropathic pain in CCI rats.The underlying mechanism might be related to the activation of peripheralα7 nicotinic receptor,further inhibiting JAK2/STAT3 signaling pathway,and eventually suppressing the expressions of TNF-αand c-fos.