Effects of interleukin-10 treated macrophages on bone marrow mesenchymal stem cells via signal transducer and activator of transcription 3 pathway

BACKGROUND Alveolar bone defects caused by inflammation are an urgent issue in oral implant surgery that must be solved.Regulating the various phenotypes of macrophages to enhance the inflammatory environment can significantly affect the progression of diseases and tissue engineering repair process.AIM To assess the influence of interleukin-10(IL-10)on the osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)following their interaction with macrophages in an inflammatory environment.METHODS IL-10 modulates the differentiation of peritoneal macrophages in Wistar rats in an inflammatory environment.In this study,we investigated its impact on the proliferation,migration,and osteogenesis of BMSCs.The expression levels of signal transducer and activator of transcription 3(STAT3)and its activated form,phos-phorylated-STAT3,were examined in IL-10-stimulated macrophages.Subsequently,a specific STAT3 signaling inhibitor was used to impede STAT3 signal activation to further investigate the role of STAT3 signaling.RESULTS IL-10-stimulated macrophages underwent polarization to the M2 type through substitution,and these M2 macrophages actively facilitated the osteogenic differentiation of BMSCs.Mechanistically,STAT3 signaling plays a crucial role in the process by which IL-10 influences macrophages.Specifically,IL-10 stimulated the activation of the STAT3 signaling pathway and reduced the macrophage inflammatory response,as evidenced by its diminished impact on the osteogenic differentiation of BMSCs.CONCLUSION Stimulating macrophages with IL-10 proved effective in improving the inflammatory environment and promoting the osteogenic differentiation of BMSCs.The IL-10/STAT3 signaling pathway has emerged as a key regulator in the macrophage-mediated control of BMSCs’osteogenic differentiation.

STAT3-Dependent Effects of Polymeric Immunoglobulin Receptor in Regulating Interleukin-17 Signaling and Preventing Autoimmune Hepatitis

One-third of patients with autoimmune hepatitis(AIH)have cirrhosis at the time of diagnosis.The relevance of these variables,although unknown,is believed to be critical in AIH because of suspected interactions between the gut microbiome and genetic factors.Dysbiosis of the gut flora and elevated polymeric immunoglobulin receptor(pIgR)levels have been observed in both patients and mouse models.Moreover,there is a direct relationship between pIgR expression and transaminase levels in patients with AIH.In this study,we aimed to explore how pIgR influences the secretion of regenerating islet-derived 3 beta(Reg3b)and the flora composition in AIH using in vivo experiments involving patients with AIH and a concanavalin A-induced mouse model of AIH.Reg3b expression was reduced in pIgR gene(Pigr)-knockout mice compared to that in wild-type mice,leading to increased microbiota disruption.Conversely,exogenous pIgR supplementation increased Reg3b expression and maintained microbiota homeostasis.RNA sequencing revealed the participation of the interleukin(IL)-17 signaling pathway in the regulation of Reg3b through pIgR.Furthermore,the introduction of external pIgR could not restore the imbalance in gut microbiota in AIH,and the decrease in Reg3b expression was not apparent following the inhibition of signal transducer and activator of transcription 3(STAT3).In this study,pIgR facilitated the upregulation of Reg3b via the STAT3 pathway,which plays a crucial role in preserving the balance of the intestinal microbiota in AIH.Through this research,we discovered new molecular targets that can be used for the diagnosis and treatment of AIH.

Mechanism of Yanghe Pingchaun granules on airway remodeling in asthmatic rats based on IL-6/JAK2/STAT3 signaling axis

Objective: To investigate the effects of Yanghe Pingchuan Granules on airway remodeling in asthmatic rats, and to explore the mechanism of Interleukin-6/Janus kinase 2/ Signal transducing activator of transcription 3(IL-6/JAK2/STAT3) signal axis. Methods: We separated 42 healthy male SD rats into two groups, a control group (7) and a model group (35).The model group was sensitized with a combination of ovalbumin (OVA) and aluminum hydroxide for 2 weeks, while the control group was given an equal amount of physiological saline.After 2 weeks, the modeling group was randomly divided into Model group, Yanghe Pingchuan Granules high, medium and low dose groups and Dexamethasone group, each group consisted of 7 animals. After 4 weeks, OVA atomization and gavage were used for stimulation and treatment. Yanghe Pingchuan Granules high, middle and low groups were given 15.48, 7.74, 3.87 g∙kg-1 Yanghe Pingchuan Granules daily, dexamethasone group was given 0.0625 mg∙kg-1 dexamethasone daily, and the other groups were given the same amount of normal saline. HE, PAS and Masson staining were used to observe the lung histopathological changes in rats. The levels of interleukin-6, IL-23 and IL-17A were detected by ELISA. The expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 in lung tissues were detected by Western blot. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the mRNA expression levels of IL-6, JAK2 and STAT3 in rat lung tissue. Results: The lung tissue structure of the model group was severely damaged compared to the control group, accompanied by a great many of inflammatory cell infiltration, goblet cell hyperplasia, subepithelial collagen fiber deposition and airway epithelial thickening were more obvious. The expressions of IL-6, IL- 23 and IL-17A in serum were significantly increased (P<0.01), the protein expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 and the mRNA expression levels of IL-6, JAK2 and STAT3 in lung tissue were significantly increased (P<0.01);Compared with the model group, inflammatory cell infiltration, goblet cell proliferation, subepithelial collagen fiber deposition and airway epithelial thickening were significantly reduced in each administration group, and the expressions of IL-6, IL-23 and IL-17A in serum were significantly decreased (P< 0.01). The protein expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 and mRNA expression levels of IL-6, JAK2 and STAT3 in lung tissue were significantly decreased (P<0.01). Conclusion: Yanghe Pingchuan Granules can significantly alleviate airway remodeling in asthmatic rats, and its mechanism may be through inhibiting the IL-6/JAK2/STAT3 signal axis.

Gossypol acetic acid regulates leukemia stem cells by degrading LRPPRC via inhibiting IL-6/JAK1/STAT3 signaling or resulting mitochondrial dysfunction

BACKGROUND Leukemia stem cells(LSCs)are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia(AML),as they are protected by the bone marrow microenvironment(BMM)against conventional therapies.Gossypol acetic acid(GAA),which is extracted from the seeds of cotton plants,exerts anti-tumor roles in several types of cancer and has been reported to induce apoptosis of LSCs by inhibiting Bcl2.AIM To investigate the exact roles of GAA in regulating LSCs under different microenvironments and the exact mechanism.METHODS In this study,LSCs were magnetically sorted from AML cell lines and the CD34+CD38-population was obtained.The expression of leucine-rich pentatricopeptide repeat-containing protein(LRPPRC)and forkhead box M1(FOXM1)was evaluated in LSCs,and the effects of GAA on malignancies and mitochondrial RESULTS LRPPRC was found to be upregulated,and GAA inhibited cell proliferation by degrading LRPPRC.GAA induced LRPPRC degradation and inhibited the activation of interleukin 6(IL-6)/janus kinase(JAK)1/signal transducer and activator of transcription(STAT)3 signaling,enhancing chemosensitivity in LSCs against conventional chemotherapies,including L-Asparaginase,Dexamethasone,and cytarabine.GAA was also found to downregulate FOXM1 indirectly by regulating LRPPRC.Furthermore,GAA induced reactive oxygen species accumulation,disturbed mitochondrial homeostasis,and caused mitochondrial dysfunction.By inhibiting IL-6/JAK1/STAT3 signaling via degrading LRPPRC,GAA resulted in the elimination of LSCs.Meanwhile,GAA induced oxidative stress and subsequent cell damage by causing mitochondrial damage.CONCLUSION Taken together,the results indicate that GAA might overcome the BMM protective effect and be considered as a novel and effective combination therapy for AML.

Galectin 2 regulates JAK/STAT3 signaling activity to modulate oral squamous cell carcinoma proliferation and migration in vitro

Background:Galectin 2(LGALS2)is a protein previously reported to serve as a mediator of disease progression in a range of cancers.The function of LGALS2 in oral squamous cell carcinoma(OSCC),however,has yet to be explored,prompting the present study to address this literature gap.Methods:Overall,144 paired malignant tumor tissues and paracancerous OSCC patient samples were harvested and the LGALS2 expression levels were examined through qPCR and western immunoblotting.The LGALS2 coding sequence was introduced into the pcDNA3.0 vector,to enable the overexpression of this gene,while an LGALS2-specific shRNA and corresponding controls were also obtained.The functionality of LGALS2 as a regulator of the ability of OSCC cells to grow and undergo apoptotic death in vitro was assessed through EdU uptake and CCK-8 assays,and flow cytometer,whereas a Transwell system was used to assess migratory activity and invasivity.An agonist of the Janus Kinase 2(JAK2)/Signal Transducer and Activator of Transcription 3(STAT3)pathway was also used to assess the role of this pathway in the context of LGALS2 signaling.Results:Here,we found that lower LGALS2 protein and mRNA expression were evident in OSCC tumor tissue samples,and these expression levels were associated with clinicopathological characteristics and patient survival outcomes.Silencing LGALS2 enhanced proliferation in OSCC cells while rendering these cells better able to resist apoptosis.The opposite was instead observed after LGALS2 was overexpressed.Mechanistically,the ability of LGALS2 to suppress the progression of OSCC was related to its ability to activate the JAK/STAT3 signaling axis.Conclusion:Those results suggest a role for LGALS2 as a suppressor of OSCC progression through its ability to modulate JAK/STAT3 signaling,supporting the potential utility of LGALS2 as a target for efforts aimed at treating OSCC patients.

18β-glycyrrhetinic acid promotes gastric cancer cell autophagy and inhibits proliferation by regulating miR-328-3p/signal transducer and activator of transcription 3

BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GRA)has a variety of pharmacological effects.The aim of this study was to explore the effective target of 18β-GRA in the treatment of GC,in order to provide effective ideas for the clinical prevention and treatment of GC.AIM To investigate the mechanism of 18β-GRA in inhibiting cell proliferation and promoting autophagy flux in GC cells.METHODS Whole transcriptomic analyses were used to analyze and screen differentially expressed microRNAs(miRNAs)in GC cells after 18β-GRA intervention.Lentivirus-transfected GC cells and the Cell Counting Kit-8 were used to detect cell proliferation ability,cell colony formation ability was detected by the clone formation assay,and flow cytometry was used to detect the cell cycle and apoptosis.A nude mouse transplantation tumor model of GC cells was constructed to verify the effect of miR-328-3p overexpression on the tumorigenicity of GC cells.Tumor tissue morphology was observed by hematoxylin and eosin staining,and microtubule-associated protein light chain 3(LC3)expression was detected by immunohistochemistry.TransmiR,STRING,and miRWalk databases were used to predict the relationship between miR-328-3p and signal transducer and activator of transcription 3(STAT3)-related information.Expression of STAT3 mRNA and miR-328-3p was detected by quantitative polymerase chain reaction(qPCR)and the expression levels of STAT3,phosphorylated STAT3(p-STAT3),and LC3 were detected by western blot analysis.The targeted relationship between miR-328-3p and STAT3 was detected using the dual-luciferase reporter gene system.AGS cells were infected with monomeric red fluorescent protein-green fluorescent protein-LC3 adenovirus double label.LC3 was labeled and autophagy flow was observed under a confocal laser microscope.RESULTS The expression of miR-328-3p was significantly upregulated after 18β-GRA intervention in AGS cells(P=4.51E-06).Overexpression of miR-328-3p inhibited GC cell proliferation and colony formation ability,arrested the cell cycle in the G0/G1 phase,promoted cell apoptosis,and inhibited the growth of subcutaneous tumors in BALB/c nude mice(P<0.01).No obvious necrosis was observed in the tumor tissue in the negative control group(no drug intervention or lentivirus transfection)and vector group(the blank vector for lentivirus transfection),and more cells were loose and necrotic in the miR-328-3p group.Bioinformatics tools predicted that miR-328-3p has a targeting relationship with STAT3,and STAT3 was closely related to autophagy markers such as p62.After overexpressing miR-328-3p,the expression level of STAT3 mRNA was significantly decreased(P<0.01)and p-STAT3 was downregulated(P<0.05).The dual-luciferase reporter gene assay showed that the luciferase activity of miR-328-3p and STAT33’untranslated regions of the wild-type reporter vector group was significantly decreased(P<0.001).Overexpressed miR-328-3p combined with bafilomycin A1(Baf A1)was used to detect the expression of LC3 II.Compared with the vector group,the expression level of LC3 II in the overexpressed miR-328-3p group was downregulated(P<0.05),and compared with the Baf A1 group,the expression level of LC3 II in the overexpressed miR-328-3p+Baf A1 group was upregulated(P<0.01).The expression of LC3 II was detected after intervention of 18β-GRA in GC cells,and the results were consistent with the results of miR-328-3p overexpression(P<0.05).Additional studies showed that 18β-GRA promoted autophagy flow by promoting autophagosome synthesis(P<0.001).qPCR showed that the expression of STAT3 mRNA was downregulated after drug intervention(P<0.05).Western blot analysis showed that the expression levels of STAT3 and p-STAT3 were significantly downregulated after drug intervention(P<0.05).CONCLUSION 18β-GRA promotes the synthesis of autophagosomes and inhibits GC cell proliferation by regulating the miR-328-3p/STAT3 signaling pathway.

Apigenin ameliorates imiquimod-induced psoriasis in C57BL/6J mice by inactivating STAT3 and NF-κB

Psoriasis is a chronic autoimmune disease featured by patches on the skin.It is caused by malfunction of immune cells and keratinocytes with inflammation as one of its key features.Apigenin(API)is a natural flavonoid with anti-inflammatory and immunoregulatory properties.Therefore,we speculated that API can ameliorate psoriasis,and determined its effect on the development of psoriasis by using imiquimod(IMQ)-induced psoriasis mouse model.Our results showed that API attenuated IMQ-induced phenotypic changes,such as erythema,scaling and epidermal thickening,and improved splenic hyperplasia.Abnormal differentiation of immune cells was restored in API-treated mice.Mechanistically,we revealed that API is a key regulator of signal transducer activator of transcription 3(STAT3).API regulated immune responses by reducing interleukin-23(IL-23)/STAT3/IL-17A axis.Moreover,it suppressed IMQ-caused cell hyperproliferation by inactivating STAT3 through regulation of extracellular signal-regulated kinase 1/2 and nuclear factor-κB(NF-κB)pathway.Furthermore,API reduced expression of inflammatory cytokines through inactivation of NF-κB.Taken together,our study demonstrates that API can ameliorate psoriasis and may be considered as a strategy for psoriasis treatment.

神经肌肉电刺激通过调控白细胞介素6/信号转导子及转录激活子3信号通路促进脊髓损伤后小鼠运动功能恢复

目的观察神经肌肉电刺激(NMES)对脊髓损伤后小鼠白细胞介素6(IL-6)/STAT3信号通路的影响,探讨其对运动功能恢复的机制。方法选取SPF级小鼠72只随机分成假手术(sham)组、脊髓损伤组(SCI)和NMES组。利用BMS评分、斜坡实验与电生理(EMG)评估小鼠脊髓损伤后肢体运动恢复情况。Western blotting和Real-time PCR检测各组小鼠脊髓组织中相关炎症因子、IL-6/STAT3信号通路与胶质纤维酸性蛋白(GFAP)和脑源性神经营养因子(BDNF)的表达。HE染色观察各组小鼠脊髓形态结构。结果NMES组BMS评分和小鼠斜坡实验均高于SCI组(P<0.05);NMES组小鼠运动诱发电位(MEP)最大振幅高于SCI组(P<0.05);NMES组脊髓组织TNF-α、IL-12A与GFAP表达量均低于SCI组(P<0.05),TGF-β、IL-10与BDNF表达量均高于SCI组(P<0.05);与SCI组相比,NMES组小鼠脊髓空洞较少,脊髓形态修复较好;与SCI组相比,NMES组IL-6/STAT3信号通路蛋白表达均低于SCI组(P<0.05)。结论神经肌肉电刺激通过抑制IL-6/STAT3信号通路发挥抗炎作用,从而促进脊髓损伤后小鼠后肢运动功能的恢复。

化瘀止痛贴膏调节IL-6/STAT3信号通路对急性软组织损伤大鼠炎症反应的影响

目的探讨化瘀止痛贴膏调节白细胞介素-6(IL-6)/信号转导与转录激活子3(STAT3)信号通路对急性软组织损伤(ASTI)大鼠炎症反应的影响。方法将SPF级SD大鼠随机分为对照组、模型组、化瘀止痛贴膏低、中、高剂量组、精制狗皮膏组。利用机械冲击挫伤法建立ASTI动物模型,建模成功后,各组贴敷相应药物,1次/d,每次给药8 h,连续7 d。对大鼠进行ASTI损伤评分;采用血液流变检测仪检测血液流变学指标;苏木精和伊红(HE)染色法观察大鼠损伤部位肌肉组织病理变化;酶联免疫吸附法(ELISA)检测各组大鼠损伤部位肌肉组织中IL-6、IL-β、肿瘤坏死因子-α(TNF-α)水平;实时荧光定量PCR(qRT-PCR)法检测损伤部位肌肉组织中IL-6与STAT3 mRNA表达;蛋白免疫印迹(Western blot)法检测大鼠损伤部位肌肉组织中IL-6/STAT3信号通路蛋白表达。结果与对照组比较,模型组大鼠软组织损伤评分、全血黏度、血浆黏度、红细胞压积、肌肉组织病理学评分、IL-6、IL-β、TNF-α水平、IL-6与STAT3 mRNA表达水平及IL-6、p-STAT3/STAT3蛋白表达水平升高(均P<0.05);与模型组比较,化瘀止痛贴膏低、中、高剂量组和狗皮膏药组大鼠软组织损伤评分、全血黏度、血浆黏度、红细胞压积、肌肉组织病理学评分、IL-6、IL-β、TNF-α水平、IL-6与STAT3 mRNA表达水平及IL-6、p-STAT3/STAT3蛋白表达水平降低(均P<0.05);化瘀止痛贴膏高剂量组与精制狗皮膏组大鼠以上指标差异均无统计学意义(P>0.05)。结论化瘀止痛贴膏可能通过下调IL-6/STAT3信号通路缓解ASTI大鼠的炎症反应。

Regulation and function of signal transducer and activator of transcription 3

Signal transducer and activator of transcription 3(STAT3), a member of the STAT family, is a key regulator of many physiological and pathological processes. Significant progress has been made in understanding the transcriptional control, posttranslational modification, cellular localization and functional regulation of STAT3. STAT3 can translocate into the nucleus and bind to specific promoter sequences, thereby exerting transcriptional regulation. Recent studies have shown that STAT3 can also translocate into mitochondria, participating in aerobic respiration and apoptosis. In addition, STAT3 plays an important role in inflammation and tumorigenesis by regulating cell proliferation, differentiation and metabolism. Conditional knockout mouse models make it possible to study the physiological function of STAT3 in specific tissues and organs. This review summarizes the latest advances in the understanding of the expression, regulation and function of STAT3 in physiological and tumorigenic processes.

Inhibition of signal transducer and activator of transcription 3 expression by RNA interference suppresses invasion through inducing anoikis in human colon cancer cells

AIM:To investigate the roles and mechanism of signal transducer and activator of transcription 3 (STAT3) in invasion of human colon cancer cells by RNA interference. METHODS: Small interfering RNA (siRNA) targeting Signal transducer and activator of transcription 3 (STAT3) was transfected into HT29 colon cancer cells. STAT3 protein level and DNA-binding activity of STAT3 was evaluated by western blotting and electrophoretic mobility shift assay (EMSA), respectively. We studied the anchorage-independent growth using colony formation in soft agar, and invasion using the boyden chamber model, anoikis using DNA fragmentation assay and terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL), respectively. Western blot assay was used to observe the protein expression of Bcl-xL and survivin in colon cancer HT29 cells. RESULTS: RNA interference (RNAi) mediated by siRNA leads to suppression of STAT3 expression in colon cancer cell lines. Suppression of STAT3 expression by siRNA could inhibit anchorage-independent growth, and invasion ability, and induces anoikis in the colon cancer cell line HT29. It has been shown that knockdown of STAT3 expression by siRNA results in a reduction in expression of Bcl-xL and survivin in HT29 cells. CONCLUSION: These results suggest that STAT3 siRNA can inhibit the invasion ability of colon cancer cells through inducing anoikis, which antiapoptotic genes survivin and Bcl-xL contribute to regulation of anoikis.These studies indicate STAT3 siRNA could be a useful therapeutic tool for the treatment of colon cancer.

Signal transducer and activator of transcription 3 promotes the Warburg effect possibly by inducing pyruvate kinase M2 phosphorylation in liver precancerous lesions

BACKGROUND Study shows that signal transducer and activator of transcription 3(STAT3) can increase the Warburg effect by stimulating hexokinase 2 in breast cancer and upregulate lactate dehydrogenase A and pyruvate dehydrogenase kinase 1 in myeloma. STAT3 and pyruvate kinase M2(PKM2) can also be activated and enhance the Warburg effect in hepatocellular carcinoma. Precancerous lesions are critical to human and rodent hepatocarcinogenesis. However, the underlying molecular mechanism for the development of liver precancerous lesions remains unknown. We hypothesized that STAT3 promotes the Warburg effect possibly by upregulating p-PKM2 in liver precancerous lesions in rats.AIM To investigate the mechanism of the Warburg effect in liver precancerous lesions in rats.METHODS A model of liver precancerous lesions was established by a modified Solt-Farber method. The liver pathological changes were observed by HE staining and immunohistochemistry. The transformation of WB-F344 cells induced with Nmethyl-N'-nitro-N-nitrosoguanidine and hydrogen peroxide was evaluated by the soft agar assay and aneuploidy. The levels of glucose and lactate in the tissue and culture medium were detected with a spectrophotometer. The protein levels of glutathione S-transferase-π, proliferating cell nuclear antigen(PCNA), STAT3,and PKM2 were examined by Western blot and immunofluorescence.RESULTS We found that the Warburg effect was increased in liver precancerous lesions in rats. PKM2 and p-STAT3 were upregulated in activated oval cells in liverprecancerous lesions in rats. The Warburg effect, p-PKM2, and p-STAT3 expression were also increased in transformed WB-F344 cells. STAT3 activation promoted the clonal formation rate, aneuploidy, alpha-fetoprotein expression,PCNA expression, G1/S phase transition, the Warburg effect, PKM2 phosphorylation, and nuclear translocation in transformed WB-F344 cells.Moreover, the Warburg effect was inhibited by stattic, a specific inhibitor of STAT3, and further reduced in transformed WB-F344 cells after the intervention for PKM2.CONCLUSION The Warburg effect is initiated in liver precancerous lesions in rats. STAT3 activation promotes the Warburg effect by enhancing the phosphorylation of PKM2 in transformed WB-F344 cells.

Silencing of signal transducer and activator of transcription 3 expression by RNA interference suppresses growth of human hepatocellular carcinoma in tumor-bearing nude mice

AIM： To explore the effect of silencing of signal transducer and activator of transcription 3 （STAT3） expression by RNA interference （RNAi） on growth of human hepatocellular carcinoma （HCC） in tumorbearing nude mice in vivo.METHODS： To construct the recombinant plasmid of pSilencer 3.0-H1-STAT3-siRNA-GFP （pSHI-siRNA- STAT3） and establish the tumor-bearing nude mouse model of the HCC cell line SMMC7721, we used intratumoral injection together with electroblotting to transfect the recombinant plasmid pSHI-siRNA- STAT3 into the transplanted tumor. The weight of the nude mice and tumor volumes were recorded. STAT3 gene transcription was detected by semi-quantitative reverse transcription polymerase chain reaction （RT- PCR）. Level of protein expression and location of STAT3 were determined by Western blotting and immunohistochemical staining. STAT3-related genes such as survivin, c-myc, VEGF, p53 and caspase3 mRNA and protein expression were detected in tumor tissues at the same time. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） assay was used to detect apoptosis of tumor cells.RESULTS： The weight of the treated nude mice increased, and the tumor volume decreased markedly compared with those of the mock-treated and negative control groups （P 〈 0.01）. The results of RT-PCR and Western blotting showed that mRNA and protein levels of STAT3 declined markedly in the treated group. The change in STAT3-related gene expression in tumor tissues at the mRNA and protein level also varied, the expression of survivin, VEGF and c-myc were obviously reduced, and expression of p53 and caspase3 increased （P 〈 0.01）. Most of the tumor tissue ceils in the treated group developed apoptosis that was detected by TUNEL assay.CONCLUSION： Silencing of STAT3 expression by RNAi significantly inhibits expression of STAT3 mRNA and protein, and suppresses growth of human HCC in tumor-bearing nude mice. The mechanism may be related to down-regulation of survivin, VEGF and c-myc and up-regulation of p53 and caspase3 expression. Accordingly, the STAT3 gene may act as an important and effective target in gene therapy of HCC.

Downregulation of signal transducer and activator of transcription 3 by sorafenib:A novel mechanism for hepatocellular carcinoma therapy

Hepatocellular carcinoma is one of the most common cancers worldwide,and a leading cause of cancer-related death.Owing to unsatisfactory clinical outcomes under the current standard of care,there is a need to search for and identify novel and potent therapeutic targets to improve patient outcomes.Sorafenib is the first and only approved targeted therapy for the treatment of hepatocellular carcinoma.Besides functioning as a multiple tyrosine kinase,sorafenib also acts via a kinase-independent mechanism to target signal transducer and activator of transcription 3(STAT3) signaling in hepatocellular carcinoma cells.STAT3 is a key regulator of inflammation,cell survival,and tumorigenesis of liver cells,and the high percentage of hepatocellular carcinoma cells with constitutively active STAT3 justifies targeting it for the development of novel therapeutics.Sorafenib inactivates STAT3 and STAT3-related signaling by inducing a conformational change in and releasing the autoinhibition of Src homology region 2 domaincontaining phosphatase-1.This phosphatase negatively regulates STAT3 activity,which leads to the subsequent apoptosis of cancer cells.The novel anti-cancer property of sorafenib will be discussed in this review,not only adding information regarding its mechanism of action but also providing an innovative approach for the development of cancer therapeutics in the future.

Diffusion-weighted magnetic resonance imaging reflects activation of signal transducer and activator of transcription 3 during focal cerebral ischemia/reperfusion

Signal transducer and activator of transcription（STAT）is a unique protein family that binds to DNA,coupled with tyrosine phosphorylation signaling pathways,acting as a transcriptional regulator to mediate a variety of biological effects.Cerebral ischemia and reperfusion can activate STATs signaling pathway,but no studies have confirmed whether STAT activation can be verified by diffusion-weighted magnetic resonance imaging（DWI）in rats after cerebral ischemia/reperfusion.Here,we established a rat model of focal cerebral ischemia injury using the modified Longa method.DWI revealed hyperintensity in parts of the left hemisphere before reperfusion and a low apparent diffusion coefficient.STAT3 protein expression showed no significant change after reperfusion,but phosphorylated STAT3 expression began to increase after 30 minutes of reperfusion and peaked at 24 hours.Pearson correlation analysis showed that STAT3 activation was correlated positively with the relative apparent diffusion coefficient and negatively with the DWI abnormal signal area.These results indicate that DWI is a reliable representation of the infarct area and reflects STAT phosphorylation in rat brain following focal cerebral ischemia/reperfusion.

Caprylic Acid Improves Lipid Metabolism, Suppresses the Inflammatory Response and Activates the ABCA1/p-JAK2/pSTAT3 Signaling Pathway in C57BL/6J Mice and RAW264.7 Cells

Objective This study aimed to investigate the effects of caprylic acid(C8:0)on lipid metabolism and inflammation,and examine the mechanisms underlying these effects in mice and cells.Methods Fifty-six 6-week-old male C57BL/6J mice were randomly allocated to four groups fed a highfat diet(HFD)without or with 2%C8:0,palmitic acid(C16:0)or eicosapentaenoic acid(EPA).RAW246.7 cells were randomly divided into five groups:normal,lipopolysaccharide(LPS),LPS+C8:0,LPS+EPA and LPS+cAMP.The serum lipid profiles,inflammatory biomolecules,and ABCA1 and JAK2/STAT3 mRNA and protein expression were measured.Results C8:0 decreased TC and LDL-C,and increased the HDL-C/LDL-C ratio after injection of LPS.Without LPS,it decreased TC in mice(P<0.05).Moreover,C8:0 decreased the inflammatory response after LPS treatment in both mice and cells(P<0.05).Mechanistic investigations in C57BL/6J mouse aortas after injection of LPS indicated that C8:0 resulted in higher ABCA1 and JAK2/STAT3 expression than that with HFD,C16:0 and EPA,and resulted in lower TNF-α,NF-κB mRNA expression than that with HFD(P<0.05).In RAW 264.7 cells,C8:0 resulted in lower expression of pNF-κBP65 than that in the LPS group,and higher protein expression of ABCA1,p-JAK2 and p-STAT3 than that in the LPS and LPS+cAMP groups(P<0.05).Conclusion Our studies demonstrated that C8:0 may play an important role in lipid metabolism and the inflammatory response,and the mechanism may be associated with ABCA1 and the p-JAK2/p-STAT3 signaling pathway.

基于IL-6/JAK2/STAT3信号通路探讨灰树花提取物对溃疡性结肠炎大鼠结肠组织炎症反应的影响

目的:探讨灰树花提取物通过调控白细胞介素6(IL-6)/蛋白酪氨酸激酶2(JAK2)/信号转导和激活因子3(STAT3)信号通路,对溃疡性结肠炎(UC)大鼠结肠组织炎症反应的影响及作用机制。方法:将40只SD大鼠随机分为空白对照组、UC模型组、灰树花治疗组、西药治疗组、联合治疗组,每组8只。采用3%DSS自由饮用法7 d建立UC大鼠模型后,治疗组分别灌胃灰树花提取物10 mg/(kg·d)、柳氮磺吡啶0.3 g/(kg·d)及等量两种药物,连续14 d。实验期间观察大鼠一般状态,计算疾病活动指数(DAI)评分;采用HE染色法观察大鼠结肠组织病理改变;Western blot检测大鼠结肠组织IL-6、JAK2、STAT3、pSTAT3蛋白表达水平;ELISA检测大鼠血清中IL-6含量;免疫组化法测定大鼠结肠组织中IL-6R、MPO蛋白含量及表达情况。结果:与空白对照组比较,UC模型组大鼠一般状态欠佳,DAI评分升高,HE染色可见明显的组织黏膜损伤与炎症细胞浸润;结肠组织IL-6、JAK2、STAT3、p-STAT3蛋白表达水平及IL-6R、MPO含量均显著升高(P<0.01);血清中IL-6含量显著升高(P<0.01),差异有统计学意义。与UC模型组比较,各治疗组大鼠的一般状态均有所改善,DAI评分降低,HE染色可见黏膜损伤有不同程度改善,偶见炎症细胞浸润;结肠组织IL-6、JAK2、STAT3、p-STAT3蛋白表达水平显著降低(P<0.01),结肠组织IL-6R和MPO含量及血清中IL-6含量均明显减少(P<0.01或P<0.05),差异有统计学意义。结论:灰树花提取物可通过调控IL-6/JAK2/STAT3信号通路相关因子表达,减轻UC大鼠结肠组织炎症反应。

基于IL-6/JAK2/STAT3信号轴研究阳和平喘颗粒调控哮喘大鼠气道重塑作用机制

目的:研究阳和平喘颗粒对哮喘大鼠气道重塑及白细胞介素-6(IL-6)/Janus蛋白酪氨酸激酶2(JAK2)/信号转导和转录活化因子3(STAT3)信号轴在其中的作用机制。方法:选取健康雄性SD大鼠42只,随机数字法分为正常对照组7只与造模组35只,造模组采用卵清蛋白(OVA)联合氢氧化铝腹腔注射2周的方式进行致敏,正常对照组采用等量的生理盐水;2周后将造模组随机分为模型组、阳和平喘高、中、低剂量组和地塞米松组,每组7只;后4周采用OVA雾化+灌胃的方式进行激发和治疗,阳和平喘高中低组每日分别予以15.48、7.74、3.87 g/kg阳和平喘颗粒灌胃,地塞米松组予以0.0625 mg/kg地塞米松进行灌胃,其余组灌胃等量生理盐水。HE、PAS、Masson染色观察大鼠肺组织病理学变化;ELISA检测大鼠血清中IL-6、IL-23、IL-17A水平;Western blot检测肺组织中JAK-2、P-JAK2、STAT3、P-STAT3蛋白表达量;qRT-PCR检测大鼠肺组织中IL-6、JAK2、STAT3的mRNA水平。结果:与正常对照组比较,模型组大鼠肺组织有大量炎性细胞浸润,杯状细胞增生、上皮下胶原纤维沉积、气道上皮增厚较为明显;血清中IL-6、IL-23、IL-17A水平显著升高(P<0.01),肺组织JAK-2、P-JAK2、STAT3、P-STAT3的蛋白表达量和IL-6、JAK2、STAT3的mRNA表达水平显著升高(P<0.01);与模型组比较,各给药组炎性细胞浸润、杯状细胞增生、上皮下胶原纤维沉积、气道上皮增厚程度明显减轻,血清中IL-6、IL-23、IL-17A水平显著降低(P<0.01),肺组织JAK-2、P-JAK2、STAT3、P-STAT3的蛋白表达量和IL-6、JAK2、STAT3的mRNA水平显著降低(P<0.01)。结论:阳和平喘颗粒可明显缓解哮喘大鼠气道重塑,其机制可能是通过抑制IL-6/JAK2/STAT3信号轴发挥作用。

基于IL-6/STAT3信号通路探讨miR-34a-5p过表达对溃疡性结肠炎的影响及小檗碱的干预作用

目的基于白细胞介素6(IL-6)/信号转导和转录激活因子3(STAT3)信号通路探讨微小RNA-34a-5p(miR-34a-5p)过表达对溃疡性结肠炎(UC)的影响及小檗碱(BBR)的干预作用。方法体外传代培养人结肠癌HT-29细胞。取传3代、对数生长期、生长状态良好的HT-29细胞,随机分为空白对照组、NC mimics组、miR-34a-5p mimics组,NC mimics组和miR-34a-5p mimics组分别转染NC mimics、miR-34a-5p mimics,空白对照组不予转染。转染6 h更换新鲜培养基继续培养48 h,收集细胞,采用RT-qPCR法验证转染效率。收集三组转染后细胞,采用CCK-8法检测细胞活力;分离三组培养上清液,采用ELISA法检测IL-6、IL-1β、TNF-α含量;收集三组转染后细胞,分别采用RT-qPCR法、Western blotting法检测IL-6、STAT3 mRNA和蛋白表达。取HT-29细胞,加入LPS刺激48 h,建立UC细胞模型。取UC细胞,分别加入0、2.5、5、10、20、40、80、160、320μg/mL BBR干预24 h,采用CCK-8法检测细胞活力。随机将UC细胞分为模型组和BBR组,BBR组予BBR干预24 h,模型组不予BBR干预。分离两组培养上清液,采用ELISA法检测IL-6、IL-1β、TNF-α含量;取两组干预24 h细胞,采用RT-qPCR法检测miR-34a-5p以及IL-6、STAT3mRNA表达。结果miR-34a-5p mimics组miR-34a-5p相对表达量高于NC mimics组和空白对照组(P均<0.05),NC mimics组与空白对照组比较差异无统计学意义(P>0.05)。miR-34a-5p mimics组细胞活力低于NC mimics组和空白对照组(P均<0.05),NC mimics组与空白对照组比较差异无统计学意义(P>0.05)。miR-34a-5p mimics组培养上清液IL-6、IL-1β、TNF-α含量均低于NC mimics组和空白对照组(P均<0.05),NC mimics组与空白对照组比较差异均无统计学意义(P均>0.05)。miR-34a-5p mimics组IL-6、STAT3 mRNA以及IL-6蛋白相对表达量均低于NC mimics组和空白对照组(P均<0.05),NC mimics组与空白对照组比较差异均无统计学意义(P均>0.05)。40、80、160、320μg/mL BBR干预24 h UC细胞活力均高于0、2.5、5、10、20μg/mL BBR干预24 h UC细胞(P均<0.05),故选择20μg/mL BBR进行后续实验。BBR组培养上清液IL-6、IL-1β、TNF-α含量均低于模型组(P均<0.05);BBR组miR-34a-5p相对表达量高于模型组,IL-6、STAT3 mRNA相对表达量均低于模型组(P均<0.05)。结论miR-34a-5p过表达能够通过抑制IL-6/STAT3信号通路减轻UC炎症反应;BBR则能通过上调miR-34a-5p表达和抑制IL-6/STAT3信号通路,减轻UC炎症反应,阻延UC癌变。

中医药靶向调控IL-6/JAK/STAT3通路的抗消化系统肿瘤研究进展

就近年来白细胞介素6/非受体酪氨酸蛋白激酶/信号转导和转录激活因子3(interleukin-6/janus activated kinase/signal transducer and activator of transcription 3,IL-6/JAK/STAT3)信号通路在多种消化系统肿瘤中发挥的效应、中药单体及其活性成分、中药复方对与IL-6/JAK/STAT3信号通路调控有关的消化系统肿瘤中的防治作用进行综述,探究中医药在延缓、阻抑甚至逆转炎-癌转化中发挥的作用,为防治肿瘤提供更有力的理论指导。