The aim of this paper was to investigate the effect and mechanism of paeonol on peritoneal macrophage M1 polarization in mice, explore whether the intervention action is related to the down-regulation of miR-155 and the inhibition of downstream JAK1-STAT1 pathway, and provide a new idea for the molecular mechanism of paeonol against atherosclerosis(AS). Lipopolysaccharide(LPS) and interferon-γ(IFN-γ) were used to stimulate macrophages for 24 hours to establish the M1 polarization model, and paeonol was given 24 hours before co-stimulation to provide a pre-protective effect on cells. CCK-8 assay was used to detect the cells damage induced by LPS and IFN-γ co-stimulation; flow cytometry was used to detect the expression of M1 surface markers F4/80 and CD86. ELISA was used to detect the secretion of interleukin 6(IL-6) and tumor necrosis factor-α(TNF-α) in supernatant. RT-qPCR was used to detect the expression of miR-155, and Western blot was used to detect the protein expression at JAK1-STAT1-SOCS1 pathway. The results showed that LPS and IFN-γ had no obvious damage to the cells at the optimal concentration, but they induced macrophages polarized to M1, resulted in high expression of M1 type marker factors F4/80 and CD86 on the cell surface, and increased secretion of IL-6 and TNF-α on the cell surface(P<0.05 or P<0.01). Paeonol significantly reduced the LPS and IFN-γ-induced high expression of F4/80 and CD86, the secretion of inflammatory factors IL-6 and TNF-α(P<0.05 or P<0.01), decreased the expression level of miR-155, significantly down-regulated the protein phosphorylation level of JAK1-STAT1 and up-regulated the protein expression of SOCS1(P<0.01) in RAW264.7 cells. The results showed that paeonol could inhibit M1 polarization of macrophages by down-regulating cell surface marker factors and inflammatory factors secreted by cells, which may be related to the down-regulation of miR-155 expression and the inhibition JAK1-STAT1 pathway activation.
Acetophenones ; Animals ; Macrophage Activation ; Macrophages ; Mice ; MicroRNAs ; STAT1 Transcription Factor

OBJECTIVETo investigate the roles of STAT1 and STAT2 in growth inhibition induced by phosphatidylethanolamine (PE) in human hepatoma HepG2 cells.

METHODSThe growth of HepG2 cells exposed to 0.125, 0.25, 0.5 and 1.0 mmol/L PE was assessed by MTT assay, and the expressions of STAT1 and STAT2 were analyzed using immunocytochemical assay.

RESULTSPE inhibited the growth of HepG2 cells in a dose-dependent manner and increased the expression of STAT1 and STAT2 in comparison with those in the control group. AG490, an inhibitor of JAKs, partially reversed PE-induced growth inhibition of HepG2 cells.

CONCLUSIONSTAT1 and STAT2 are involved in the growth inhibition of human hepatoma HepG2 cells induced by PE.

Apoptosis ; drug effects ; Cell Proliferation ; Hep G2 Cells ; Humans ; Phosphatidylethanolamines ; pharmacology ; STAT1 Transcription Factor ; metabolism ; STAT2 Transcription Factor ; metabolism

OBJECTIVE: To analyze the relationships between expression levels of serum microRNA-146a, STAT1 protein and clinical characteristics in children with acute lymphoblastic leukemia (ALL). METHODS: A total of 102 children diagnosed as ALL in our hospital from June 2014 to June 2016 were enrolled, and were compared by into groups according to clinical characteristics including sex, age, lymphocyte type, disease risk, chemotherapy stage and gene mutation. Fifty healthy children were chosen as control group. The relative expression of microRNA-146a and STAT1 gene was detected by real-time RT-PCR and the relative level of STAT1 protein was detected by Western blot. The difference of microRNA-146a and STAT1 protein levels between clinical factors and laboratory indexs were compared. Followed-up for 3 years, The difference of overall survival (OS) rates between ALL children with different microRNA-146a and STAT1 protein were compared. RESULTS: The levels of microRNA-146a, STAT1 mRNA and protein in ALL children were significantly higher than those in control group (P＜0.05), but there were no significantly differences in sex, age and lymphocyte type grouping in ALL children (P＞0.05). There were significantly differences in different disease risk, chemotherapy stage and gene mutation groups in ALL children (P＜0.05). Followed-up for 3 years, the OS rate of ALL children with high microRNA-146a and STAT1 protein levels were better than those with low microRNA-146a and STAT1 protein levels (P＜0.05). CONCLUSION The up-regulation of microRNA-146a and STAT1 protein may be involved in occurrence and development of ALL, which closely relates to clinical characteristics in ALL children, such as disease risk, chemotherapy stage and gene mutation.
Child ; Humans ; MicroRNAs ; genetics ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; RNA, Messenger ; STAT1 Transcription Factor ; genetics ; Up-Regulation

OBJECTIVETo investigate the role of Janus kinase-signal transducer and transcription activator (JAK-STAT) pathway in the regulation of synthesis and release of lipopolysaccharide-induced high mobility group box-1 protein (HMGB1).

METHODSPeritoneal macrophages harvested from male Wistar rats were incubated for 3 days before the experiment. The activation of Janus kinase-2 (JAK2), signal transducer and activator of transcription-1 (STAT1) and STAT3 was observed before and 10, 30, 60 and 120 mins after LPS stimulation (4 determinations at each time point) and it was expressed as A value (absorption). In addition, the cells were divided into normal control, LPS stimulation, JAK2 inhibition (with AG490 treatment 2 hours before LPS stimulation), STAT1 inhibition (with fludarabine treatment 2 hours before LPS stimulation) and STAT3 inhibition (with rapamycin treatment 2 hours before LPS stimulation) groups. The cells in all groups except control group were stimulated with LPS 3 days after culture. The expression of HMGB1 gene and its protein release in each group were determined for 4 times and were expressed as A value.

RESULTSLPS could activate JAK2, STAT1 and STAT3 within 2 hours, especially the activation of STAT3 appeared more quickly, peaking at 10 minutes after LPS stimulation (7.47 +/- 0.56). Pretreatment with the inhibitors of JAK-STAT pathway could markedly reduce the expression of HMGB1 mRNA (P < 0.01), but exerted no effect on HMGB1 release.

CONCLUSIONJAK-STAT pathway can be activated early during endotoxin challenge, and it may play a role in the regulation of HMGB1 synthesis.

Animals ; Cell Culture Techniques ; HMGB1 Protein ; biosynthesis ; Janus Kinase 2 ; metabolism ; Lipopolysaccharides ; Macrophages, Peritoneal ; metabolism ; Male ; Rats ; Rats, Wistar ; STAT1 Transcription Factor ; metabolism ; STAT3 Transcription Factor ; metabolism

OBJECTIVETo establish a new method for studying the mechanism of nuclear localization signal (NLS)-mediated nuclear translocation in living cells.

METHODSThe cells were treated with 67 mg/L 3-[(3-Cholamidopropyl)dimethylammonio]propanesulfonate (CHAPS), followed by incubation with 1 g/L wheat germ agglutinin (WGA), and their effects on interferon- γ (IFN-γ)-induced nuclear translocation of signal transducer and activator of transcription 1 (STAT1) were observed.

RESULTSTreatment with CHAPS alone had no effect on IFN-γ-induced nuclear translocation of STAT1, while this process was blocked by further WGA incubation.

CONCLUSIONWe established a new, simple but effective method for studying the mechanism of NLS-mediated nuclear translocation in living cells by perforating the cell membrane with CHAPS treatment.

Active Transport, Cell Nucleus ; Cell Nucleus ; metabolism ; Cholic Acids ; Cytological Techniques ; HeLa Cells ; Humans ; Interferon-gamma ; metabolism ; Nuclear Localization Signals ; metabolism ; STAT1 Transcription Factor ; metabolism ; Signal Transduction

OBJECTIVETo explore the effect of rosiglitazone on the activity of signal transducer and activator of transcription 1 in rats with severe acute pancreatitis.

METHODSFifty-four male Wistar rats were randomly allocated into three groups (n = 18). SO group: sham-operated animals served as control, operation was executed and sodium chloride but not sodium taurocholate was injected. SAP group: SAP was induced by the retrograde injection of 5% sodium taurocholate into the biliopancreatic duct. ROSI group: same as SAP group, but rosiglitazone (6 mg/kg) was administered intravenously 30 min before operation. Rats in each group were sacrificed at 3,6 and 12 h after operation. The levels of serum amylase and histologic scores of pancreatic tissue were measured. The expression of TNF-alpha mRNA in pancreatic tissue were determined by reverse transcription-polymerase chain reaction (RT-PCR). The expression of phosphorylated STAT1 in pancreatic tissue was assayed by immunohistochemistry.

RESULTSCompared to SO group, the levels of serum amylase and phosphorylated STAT1, TNF-alpha mRNA and histologic scores of pancreatic tissue were significantly elevated at the same time points after SAP (P < 0.01). The levels of these detection in ROSI group were lower than those of the SAP group at the same time points (P < 0.05), but higher than SO group (P < 0.05).

CONCLUSIONSSTAT1 was activated in severe acute pancreatitis. Rosiglitazone has a protective effects in rats with severe acute pancreatitis. The mechanism of its protective effects maybe that it inhibits the activation of JAK/STAT pathway, which can down-regulate the expression of TNF-alpha mRNA and block the the inflammatory cascade partially.

Acute Disease ; Animals ; Disease Models, Animal ; Male ; Pancreas ; metabolism ; pathology ; Pancreatitis ; drug therapy ; metabolism ; pathology ; Random Allocation ; Rats ; Rats, Wistar ; STAT1 Transcription Factor ; metabolism ; Thiazolidinediones ; pharmacology

CARD Signaling Adaptor Proteins ; physiology ; Candidiasis ; genetics ; Genetic Predisposition to Disease ; Humans ; Interleukin-17 ; genetics ; Mutation ; STAT1 Transcription Factor ; genetics ; Toll-Like Receptor 3 ; genetics

Interferon response is the first line of host defense against virus infection. Recent years have witnessed tremendous progress in understanding of fish innate response to virus infection, especially in fish interferon antiviral response. A line of fish genes involved in interferon antiviral response have been identified and functional studies further reveal that fish possess an IFN antiviral system similar to mammals. However, fish virus-induced interferon genes contain introns similar to mammalian type III interferon genes although they encode proteins similar to type I interferons, which makes it hard to understand the evolution of vertebrate interferon genes directly resulting in a debate on nomenclature of fish interferon genes. Actually, fish display some unique mechanisms underlying interferon antiviral response. This review documents the recent progress on fish interferon response and its molecular mechanism.
Animals ; Fish Diseases ; immunology ; virology ; Fish Proteins ; genetics ; metabolism ; Fishes ; immunology ; virology ; Gene Expression Regulation ; Interferons ; genetics ; immunology ; STAT1 Transcription Factor ; metabolism ; Virus Diseases ; immunology ; veterinary

Fucoidan, a sulfated polysaccharide is found in several types of edible brown algae. It has shown numerous biological activities; however, the molecular mechanisms on the activity against atopic dermatitis have not been reported yet. We now examined the effects of fucoidan on chemokine production co-induced by TNF-alpha/IFN-gamma, and the possible mechanisms underlying these biological effects. Our data showed that fucoidan inhibited the TNF-alpha/IFN-gamma-induced production of thymus and activation-regulated chemokine (TARC) and macrophagederived chemokine (MDC) mRNA in human keratinocytes HaCaT cells. Also, fucoidan suppressed phosphorylation of nuclear factor kappa B (NF-kappaB) and activation of signal transducer and activator of transcription (STAT)1 in a dose-dependent manner. In addition, fucoidan significantly inhibited activation of extracellular-signal-regulated kinases (ERK) phosphorylation. These data indicate that fucoidan shows anti-inflammatory effects by suppressing the expression of TNF-alpha/IFN-gamma-induced chemokines by blocking NF-kappaB, STAT1, and ERK1/2 activation, suggestive of as used as a therapeutic application in inflammatory skin diseases, such as atopic dermatitis.
Chemokine CCL17 ; Chemokines ; Dermatitis, Atopic ; Humans* ; Keratinocytes* ; NF-kappa B* ; Phaeophyta ; Phosphorylation ; Phosphotransferases ; RNA, Messenger ; Skin Diseases ; STAT1 Transcription Factor ; Transducers

It was widely known that retinoic acid inducible gene I (RIG-I) functions as a cytosolic pattern recognition receptor that initiates innate antiviral immunity by detecting exogenous viral RNAs. However, recent studies showed that RIG-I participates in other various cellular activities by sensing endogenous RNAs under different circumstances. For example, RIG-I facilitates the therapy resistance and expansion of breast cancer cells and promotes T cell-independent B cell activation through interferon signaling activation by recognizing non-coding RNAs and endogenous retroviruses in certain situations. While in hepatocellular carcinoma and acute myeloid leukemia, RIG-I acts as a tumor suppressor through either augmenting STAT1 activation by competitively binding STAT1 against its negative regulator SHP1 or inhibiting AKT-mTOR signaling pathway by directly interacting with Src respectively. These new findings suggest that RIG-I plays more diverse roles in various cellular life activities, such as cell proliferation and differentiation, than previously known. Taken together, the function of RIG-I exceeds far beyond that of a pattern recognition receptor.
Animals ; DEAD Box Protein 58 ; genetics ; metabolism ; Mice ; RNA, Viral ; genetics ; metabolism ; STAT1 Transcription Factor ; genetics ; metabolism ; Signal Transduction ; genetics ; physiology