OBJECTIVETo explore the feasibility of regulated expansion and committed differentiation potential of JAK2 gene modified hematopoietic stem/progenitor cells in vitro.

METHODSA murine stem cell virus (MSCV) based retroviral vector MGI-F2Jak2, which encodes a green fluorescent protein (GFP) and a fusion protein containing two copies of modified FK506 binding protein (F36v) linked tyrosine kinase JAK2 was cloned. F36v served as a high-affinity binding site for dimerizer AP20187. GpE + 86 packaging cell was transfected with this vector. Bone marrow cells from C57BL/6 mice were transduced by co-cultured with irradiated (1500 cGy) GpE + 86 producer clone for 48 h. Transduced marrow cells were expanded in X-VIVO 15 and divided into four groups as follows: (1) control group; (2) AP20187 alone group; (3) SCF alone group and (4) AP20187 + SCF group. The phenotypes of the expanded cells were analyzed by directly phycoerythrin-labeled anti-Sca1, c-kit, CD(34), Gr1, CD(11b), TER119, CD(41), B220 and CD(3) monoclonal antibodies for flow cytometry. Committed differentiation, progenitor colony assay and spleen colony forming units (CFU-S) were further evaluated.

RESULTSA significant sustained outgrowth of transduced marrow cells was obtained only in the AP20187 + SCF group. Cells expanded up to 10(14)-fold after 80 days culture. The doubling time was about 30 hs. The phenotypes of the expanded cells were homogeneously strong positive for CD(34), c-kit and Sca1, while were almost negative for Gr1, CD(11b), TER119, CD(41), B220 and CD(3). Functional assay demonstrated that the expanded cells had multipotential to differentiate into granulocyte, macrophage, erythrocyte, or B-cells under different cytokines combinations. A prominent megakaryocytic differentiation was observed when cultured with SCF/Tpo/IL-11 combination. The expanded cells were also capable of forming BFU-E, CFU-GM and CFU-Mix in methylcellulose colony assay. The expanded cells over three months could still form CFU-S.

CONCLUSIONSAP20187 combined SCF mediated activation of JAK2 signaling domain can dramatically expand hematopoietic stem/progenitor cells, and the expanded cells can be regulated and committed to differentiate into multilineage cells. This system may provide important insights into stem cell biology and may be promising for gene and cell therapy.

Animals ; Cell Differentiation ; Female ; Hematopoietic Stem Cells ; cytology ; Janus Kinase 2 ; Mice ; Mice, Inbred C57BL ; Protein-Tyrosine Kinases ; genetics ; physiology ; Proto-Oncogene Proteins ; Tacrolimus ; analogs & derivatives ; pharmacology ; Transfection

Objective To explore the therapeutic effect of ethambutol tablets (EMB) on pulmonary tuberculosis (PTB) in rats and whether the action mechanism of EMB is related to Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway. Methods Sixty SD rats were assigned into a control group,a PTB group,a PTB+EMB group (30 mg/kg),and a PTB+EMB+Colivelin (JAK/STAT pathway activator) group (30 mg/kg+1 mg/kg) via the random number table method,with 15 rats in each group.The rats in other groups except the control group were injected with 0.2 ml of 5 mg/ml Mycobacterium tuberculosis suspension to establish the PTB model.After the modeling,the rats were administrated with corresponding drugs for 4 consecutive weeks (once a day).On days 1,14,and 28 of administration,the body weights of rats were measured and the Mycobacterium tuberculosis colonies were counted.Hematoxylin-eosin staining was carried out to detect the pathological changes in the lung tissue.Enzyme-linked immunosorbent assay was employed to measure the levels of interleukin(IL)-6,tumor necrosis factor-α (TNF-α),IL-1β,and interferon-γ (IFN-γ) in the serum.Flow cytometry was used to determine the levels of T lymphocyte subsets CD3+,CD4+,CD8+,and CD4+/CD8+.The 16S rRNA sequencing was performed to detect the relative abundance of the intestinal microorganisms.Western blotting was employed to determine the expression of the proteins in the JAK/STAT pathway. Results Compared with the control group,the modeling of PTB reduced the rat body weight (on days 14 and 28),increased Mycobacterium tuberculosis colonies,caused severe pathological changes in the lung tissue,and elevated the levels of IL-6,TNF-α,and IL-1β in serum and CD8+.Moreover,the modeling increased the relative abundance of Bacteroides,Peptococcus,Clostridium,Actinomyces,Lactobacillus,Verrucomicrobium,and Veillonella in the intestine,up-regulated the protein levels of phosphorylated JAK2 and phosphorylated STAT3 in the lung tissue,and lowered the levels of CD3+,CD4+,CD4+/CD8+,and IFN-γ levels (all P<0.001).Compared with the PTB group,PTB+EMB increased the rat body weight (on days 14 and 28),reduced Mycobacterium tuberculosis colonies,alleviated the pathological damage in lung tissue,lowered the levels of IL-6,TNF-α,and IL-1β in serum and CD8+.Moreover,the treatment decreased the relative abundance of Bacteroides,Peptococcus,Clostridium,Actinomyces,Lactobacillus,Verrucomicrobium,Veillonella in the intestine,down-regulated the protein levels of phosphorylated JAK2 and phosphorylated STAT3 in the lung tissue,and elevated the levels of CD3+,CD4+,CD4+/CD8+,and IFN-γ (all P<0.001).Colivelin weakened the alleviation effect of EMB on PTB (all P<0.001). Conclusion EMB can inhibit the JAK/STAT signaling pathway to alleviate the PTB in rat.
Animals ; Body Weight ; Ethambutol/pharmacology* ; Interferon-gamma/pharmacology* ; Interleukin-6/metabolism* ; Janus Kinases/pharmacology* ; Mycobacterium tuberculosis/metabolism* ; RNA, Ribosomal, 16S ; Rats ; Rats, Sprague-Dawley ; STAT Transcription Factors/pharmacology* ; Signal Transduction ; Tablets/pharmacology* ; Tuberculosis, Pulmonary/metabolism* ; Tumor Necrosis Factor-alpha/metabolism*

OBJECTIVETo elucidate the roles of JAK/STATs signal pathway on anti-proliferative effects induced by IFN-alpha in MHCC97.

METHODSAn IRF9 expression vector was transfected into MHCC97 with Dosper. The expression of IRF9, cycle regulating proteins and the forming of ISGF3 complex were detected using Western blot and EMSA, respectively. Cell proliferation and distribution were monitored using MTT and flow cytometry.

RESULTSHigh expression of IRF9 restored the anti-proliferative response of MHCC97 on IFN-alpha treatment and delayed the cell transition from S phase to G2 phase induced by IFN-alpha.

CONCLUSIONThe integrity and functions of JAK/STATs signal pathway played an important role in mediating the anti-proliferative effects of IFN-alpha in MHCC97.

Carcinoma, Hepatocellular ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Interferon-Stimulated Gene Factor 3, gamma Subunit ; genetics ; Interferon-alpha ; metabolism ; pharmacology ; Janus Kinases ; genetics ; physiology ; Liver Neoplasms ; genetics ; metabolism ; pathology ; STAT Transcription Factors ; genetics ; physiology ; Signal Transduction ; Transfection

OBJECTIVETo evaluate the effect of JAK/STAT signaling pathway activation on the transdifferentiation and secretion of transforming growth factor-beta1 (TGF-beta1) induced by high glucose in renal proximal tubular epithelial cells.

METHODSHuman kidney cells (HKC) were cultured and then divided into four groups: low glucose (LG) group, high glucose (HG) group, high mannitol (LG + M) group, and HG + AG490 group. Immunoprecipitation and Western blot analysis were used to determine the expression of tryosine phosphorylated Janus kinase 2 ( p-JAK2). The protein expressions of STAT1, STAT3, p-STAT1, and p-STAT3 and the expressions of alpha-SMA and E-Cadherin were observed by Western blot. The contents of TGF-B1, fibronectin and type I collagen in the supernatants of the cultured HKC were detected by enzyme-linked immunosorbent assay (ELISA). The expression of TGF-beta1 mRNA was measured by reverse transcription and polymerase chain reaction (RT-PCR).

RESULTSCompared with LG group, the expressions of JAK2, p-STAT1, p-STAT3, and TGF-beta1, mRNA were significantly increased in HG group from 6 to 72 hours. Meanwhile, the contents of TGF-beta1 and collagen I in the supernatants and the expression of alpha-SMA increased and the expression of E-Cadherin decreased. The expressions of JAK2, p-STAT1, p-STAT3, and TGF-beta mRNA as well as the levels of TGF-beta1 and collagen I in the supernatant s in HG + AG490 group were significantly lower than in the HG group. The expressions of alpha-SMA and E-Cadherin were also decreased in HG + AG490 group.

CONCLUSIONActivation of JAK/STAT signaling pathway may be involved in the high glucose-induced transdifferentiation and overproduction of TGF-beta1, and ECM proteins in HKCs.

Cell Line ; Cell Transdifferentiation ; Epithelial Cells ; cytology ; metabolism ; Glucose ; metabolism ; pharmacology ; Humans ; Janus Kinases ; physiology ; Kidney Tubules, Proximal ; cytology ; metabolism ; STAT Transcription Factors ; physiology ; Signal Transduction ; Transforming Growth Factor beta1 ; biosynthesis ; secretion ; Urothelium ; cytology ; metabolism

This study was aimed to determine the in vivo signal transduction pathway responsible for isoproterenol (ISO)-induced cardiac hypertrophy or remodeling. Mice were treated with ISO (15 mg/kg body weight) or vehicle by intraperitoneal injection (i.p.). Activation of mitogen-activted protein kinase (MAPK), NF-kappaB and JAK/STAT pathway in the left ventricular myocardium was measured by Western blot analysis. ISO significantly activated MAPK (ERK1/2 and p38) at early phase (5 min); biphasic activation of NF-kappaB was observed in our in vivo study; and ISO caused a delayed STAT3 activation (at 60 to 240 min) in mouse myocardium. Taken together, these results indicate that ISO activates these signal transduction pathways in different time course.
Animals ; Heart ; drug effects ; Isoproterenol ; pharmacology ; Janus Kinase 1 ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Mitogen-Activated Protein Kinases ; metabolism ; Myocardium ; metabolism ; NF-kappa B ; metabolism ; STAT3 Transcription Factor ; metabolism ; Signal Transduction ; Time Factors

OBJECTIVETo investigate the effects of simvastatin (SIM) on in vivo and in vitro cardiac hypertrophy models and changes on JAK/STAT signal pathways.

METHODSMyocardial hypertrophy was induced by Cardiotrophin-1 (CT-1) in neonatal cardiomyocytes and by abdominal aortic constriction (AC) for 4 weeks in adult SD rats. In vitro study groups were as follows (n = 3 each): (1) control, (2) CT-1 (10(-10) mol/L), (3) CT-1 + SIM (10(-6) mol/L), (4) CT-1 + AG490(JAK inhibitor, 10(-4) mol/L), (5)SIM (10(-6) mol/L), (6) AG490 (10(-4) mol/L). In vivo study groups were as follows (n = 8 each): (1) sham group, (2) AC group, (3) AC + SIM group, (4) AC + captopril group. Total protein content was measured by Lowry's method and the cell surface area was measured by phase contrast microscope. The expression of AGT mRNA and c-fos mRNA were detected by RT-PCR. Systolic blood pressure (SBP), heart weight/body weight (HW/BW) and left ventricle weight/body weight (LVW/BW) were measured. The expressions of p-JAK2 and p-STAT3 were detected by Western blot.

RESULTSThe total protein content and cardiomyocytes size were significantly increased in CT-1 treated cells and which could be blocked by SIM. The expressions of p-JAK2 and p-STAT3 as well as the expression of AGT mRNA and c-fos mRNA significantly activated by CT-1, which could be inhibited by SIM or Janus Kinase-selective inhibitor AG490. Similar as captopril, SIM also attenuated cardiac hypertrophy in AC rats as shown on reduced systolic blood pressure, heart weight to body weight, left ventricular weight to body weight ratios as well as cross sectional area of cardiomyocytes.

CONCLUSIONSIM prevented CT-1 and AC induced cardiomyocyte hypertrophy via inhibiting JAK/STAT pathways.

Animals ; Cardiomegaly ; metabolism ; prevention & control ; Cytokines ; metabolism ; Disease Models, Animal ; Hydroxymethylglutaryl-CoA Reductase Inhibitors ; metabolism ; Janus Kinases ; metabolism ; Male ; Myocardium ; metabolism ; Rats ; Rats, Sprague-Dawley ; STAT Transcription Factors ; metabolism ; Signal Transduction ; drug effects ; Simvastatin ; pharmacology

The effect of curcumin on JAK-STAT signaling pathway was investigated in hepatoma cell lines Huh7 and Hep3B. Curcumin inhibited cell proliferation and induced apoptosis of both cell lines, but Huh7 cells were more sensitive to curcumin than Hep3B cells. Curcumin (50 micromol x L(-1)) significantly increased phosphorylations of p38 (T180/Y182) and STAT-1 (S727) in Huh7 and Hep3B cells, and caused relocalization of phosphorylated-STAT-1 (Y701) from cytoplasm to nucleus in Hep3B cells. In addition, curcumin (25 and 50 micromol x L(-1)) dramatically suppressed the phosphorylation level of STAT-1 (Y701) and resulted in a significant reduction of nuclear phosphorylated-STAT-1 (Y701) in Huh7 cells.
Antineoplastic Agents, Phytogenic ; isolation & purification ; pharmacology ; Apoptosis ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; Curcuma ; chemistry ; Curcumin ; isolation & purification ; pharmacology ; Humans ; Janus Kinases ; metabolism ; Liver Neoplasms ; metabolism ; pathology ; Phosphorylation ; Plants, Medicinal ; chemistry ; STAT1 Transcription Factor ; metabolism ; Signal Transduction ; p38 Mitogen-Activated Protein Kinases ; metabolism

OBJECTIVETo examine how the thymidine phosphorylase (TP) gene expression is upregulated by interferon-alpha (IFN-alpha) in human hepatocellular carcinoma SMMC-7721 cells.

METHODSTP mRNA levels were determined by RT-PCR. Whether the JAK-STAT cascade mediates IFN-alpha-induced TP mRNA expression was studied by pretreatment with Janus Kinase (JAK) inhibitor, AG-490. Effects of IFN-alpha on TP mRNA stability were detected with additional actinomycin D.

RESULTSThe expression of TP mRNA was induced by IFN-alpha in a dose- and time-dependent manner in SMMC-7721 (human hepatocellular carcinoma) cells. TP mRNA levels rose at 8 h, reached the peak value at 12 h, and remained at a high level up to 72 h in SMMC-7721 cells treated with IFN-alpha 10000 U/ml. IFN-alpha at a dose of 5000 or 10000 U/ml up-regulated TP expression about 3 fold compared with that of non-treated cells (P < 0.05). Induction of TP mRNA expression by IFN-alpha was significantly inhibited in SMMC-7721 cells by pretreatment with AG-490, in comparison with that treated with IFN-alpha alone. Pretreatment of SMMC-7721 cells with IFN-alpha 10000 U/ml for 24 h caused a substantial stabilization of TP mRNA, with a half-live of 35.8 h, compared with 8.5 hr in the control SMMC-7721 cells.

CONCLUSIONIFN-alpha at certain doses upregulates TP mRNA expression via both JAK-STAT transcriptional activation and post-transcriptional mRNA stabilization in human hepatocellular carcinoma SMMC-7721 cells.

Carcinoma, Hepatocellular ; enzymology ; pathology ; Cell Line, Tumor ; Dose-Response Relationship, Drug ; Enzyme Inhibitors ; pharmacology ; Gene Expression Regulation, Neoplastic ; Humans ; Interferon-alpha ; administration & dosage ; pharmacology ; Janus Kinases ; metabolism ; Liver Neoplasms ; enzymology ; pathology ; RNA, Messenger ; metabolism ; STAT1 Transcription Factor ; metabolism ; Thymidine Phosphorylase ; biosynthesis ; genetics ; Transcriptional Activation ; drug effects ; Tyrphostins ; pharmacology

AIMTo discover new drugs which may be applied to diseases of the immune system, hemogenesis system diseases and tumors, several high-throughput drug screening cell models based on JAK-STAT signal pathway have been established.

METHODSFour repeats of STAT DNA binding conserved sequences were synthesized, subcloned into pGL-Luc reporter vector and stably transfected into cell lines in vitro. Cell clones with high copy numbers of STAT binding sites and reporter genes were chosen as high-throughput drug screening cell models. The cell models were tested with known anti-allergic drugs and anti-tumor drugs by determining luciferase activity. The reaction was performed in 96 well micro-plates with a final volume of 50 microL.

RESULTSThe cell models by performing rapid fluorescence assay were shown to be highly sensitive and stable after testing with cytokine and drugs. The modification of the expression plasmid simplified this method and made it more practical. It also provided good linear correlation, wide range of assay, highly sensitive and good reproducibility.

CONCLUSIONThe method can be performed by high-throughput drug screening for effective extraction of Chinese traditional herbs.

Anti-Allergic Agents ; isolation & purification ; pharmacology ; Antineoplastic Agents ; isolation & purification ; pharmacology ; Carcinoma, Hepatocellular ; pathology ; DNA-Binding Proteins ; genetics ; metabolism ; Drug Evaluation, Preclinical ; methods ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Humans ; Janus Kinase 2 ; Jurkat Cells ; metabolism ; Liver Neoplasms ; pathology ; Luciferases ; metabolism ; Protein-Tyrosine Kinases ; genetics ; metabolism ; Proto-Oncogene Proteins ; STAT3 Transcription Factor ; Signal Transduction ; Trans-Activators ; genetics ; metabolism ; Tumor Cells, Cultured

Inflammation is a part of the complex biological responses of a tissue to injury that protect the organ by removing injurious stimuli and initiating the healing process, and is considered as a mechanism of innate immunity. To identify biologically active compounds against pathogenic inflammatory and immune responses, we fractionated water, aqueous methanol and n-hexane layers from nine kinds of leguminosae and examined anti-inflammatory activity of the fractions in human keratinocytes and mouse skin. Among the fractions, rf3 and rf4, isolated from the aqueous methanol layer of Astragalus sinicus L., exhibited the strongest reactive oxygen species (ROS)-scavenging and anti-inflammatory activities as measured by inhibition of the intracellular ROS production, nuclear factor-kappaB (NF-kappaB), janus kinase (JAK)/signal transducer and activator of transcription (STAT), and phosphatidylinositol 3-kinase/Akt signaling in cytokine-stimulated human keratinocytes, as well as by effects on T-cell differentiation in mouse CD4+ T cells. In addition, topical application of rf3 and rf4 suppressed the progression of psoriasis-like dermatitis and expression of pro-inflammatory mediators in interleukin (IL)-23-injected mouse ears. Our results suggest that Astragalus sinicus L. may ameliorate chronic inflammatory skin diseases due to its antioxidant and anti-inflammatory activities via regulation of the intracellular ROS production, NF-kappaB, JAK/STAT and PI3/Akt signaling cascades as well as immune responses, and these results are the first report that Astragalus sinicus L. exhibits pharmacological activity.
Animals ; Anti-Inflammatory Agents/isolation & purification/*pharmacology/therapeutic use ; Astragalus Plant/*chemistry ; Cell Line ; Dermatitis/drug therapy ; Humans ; Interleukin-23/pharmacology ; Janus Kinases/metabolism ; Keratinocytes/*drug effects/metabolism ; Mice ; Mice, Inbred C57BL ; NF-kappa B/metabolism ; Phosphatidylinositol 3-Kinases/metabolism ; Plant Extracts/isolation & purification/*pharmacology/therapeutic use ; Proto-Oncogene Proteins c-akt/metabolism ; Reactive Oxygen Species/metabolism ; STAT Transcription Factors/metabolism ; Skin/*drug effects/metabolism