Objective To investigate the regulatory effect of suppressor of cytokine signaling 1 (SOCS1) on the proliferation and apoptosis of myelodysplastic syndrome (MDS) cells SKM-1 and its potential mechanisms. Methods SOCS1 was overexpressed in SKM-1 cells by transfection with exogenous SOCS1-overexpressing plasmid. Cell viability, cell cycle and apoptosis were analyzed with CCK-8 and flow cytometry assays, respectively. Western blot was used to evaluate the expression of proteins related to the Janus kinase 2/signal transducer and activator of transcription (JAK2/STAT) signaling pathway. Additionally, a NOD/SCID mouse model of MDS was established to record mouse body weight and survival time, assessing the impact of the SOCS1 gene on the growth of SKM-1 cells in vivo. Results Transfection of the SOCS1-overexpressing plasmid significantly increased the mRNA and protein expression levels of SOCS1 in the MDS cell line SKM-1. Overexpression of SOCS1 remarkably reduced cell viability, inhibited cell proliferation, and promoted apoptosis of SKM-1 cells, which also decreased the expression of phosphorylated-JAK2 (p-JAK2), phosphorylated-STAT3 (p-STAT3), and p-STAT5 proteins. Furthermore, in vivo experiment results showed that the body weight and survival time of mice in the SOCS1 overexpression group were significantly better than those in the MDS model group, and the number of CD45⁺ SKM-1 cells in the peripheral blood was significantly lower than that in the MDS model group, indicating that SOCS1 overexpression could inhibit the activity of SKM-1 cells in mice. Western blot results verified the protein expression level of SOCS1 in the bone marrow of mice in the SOCS1 overexpression group was significantly higher than that in the MDS model group, while the protein expression levels of p-JAK2, p-STAT3, and p-STAT5 were significantly lower than those in the MDS model group. Conclusion SOCS1 inhibits the proliferation of MDS cell line SKM-1 and promotes its apoptosis by negatively regulating the JAK2/STAT signaling pathway, making it a potential therapeutic target for myelodysplastic syndromes.
Animals ; Humans ; Mice ; Apoptosis ; Body Weight ; Bone Marrow/metabolism* ; Janus Kinase 2/metabolism* ; Mice, Inbred NOD ; Mice, SCID ; Myelodysplastic Syndromes/metabolism* ; Phosphorylation ; STAT3 Transcription Factor/metabolism* ; STAT5 Transcription Factor/metabolism* ; Suppressor of Cytokine Signaling 1 Protein/metabolism* ; Cell Proliferation

Triptolide( TP) is isolated from the traditional Chinese medicine Tripterygium wilfordii,which exhibits notable immuneregulative effect. Th17 cells involve in inflammatory response and Treg cells contribute to immune tolerance. They both play an important role in immune response. Previous studies have investigated that TP induced hepatic Th17/Treg imbalance. However,the effect of TP on spleen Th17/Treg cells remains unclear. Therefore,the aim of present study was to investigate the effect of TP on Th17/Treg cells in spleen. In this study,the effect of TP on the proliferation of splenic lymphocyte was detected by cytotoxicity test in vitro. After different concentrations of TP( 2. 5,5,20,40 nmol·L~(-1)) were given to splenic lymphocyte,cytokines secreted from the supernatant of splenic lymphocyte were detected by cytometric bead array,and the expression of suppressor of cytokine signaling( SOCS) mRNA was detected by qRT-PCR. Female C57 BL/6 mice were continuously observed for 24 h after treatment of 500 μg·kg-1 TP. The effects of TP on the splenic tissue structure and the percentage of Th17/Treg cells were examined. The results showed that the IC50 of TP was19. 6 nmol·L~(-1) in spleen lymphocytes. TP inhibited the secretion of IL-2 and IL-10 and induced the expression of SOCS-1/3 mRNA in spleen lymphocytes at the dosage of 2. 5 and 5 nmol·L~(-1) after 24 h in vitro. Administration of TP at dosage of 500 μg·kg-1 had no significant spleen toxicity in vivo. TP treatment increased the percentage of Th17 cells after 12 h and inhibited the proportion of Treg cells after 12 and 24 h. In conclusion,TP reduced the secretion of IL-2 and IL-10 through SOCS-1/3 signaling pathway,thereby induced the percentage of Th17 cells and inhibited the percentage of Treg cells.
Animals ; Cytokines ; metabolism ; Diterpenes ; pharmacology ; Epoxy Compounds ; pharmacology ; Female ; Mice ; Mice, Inbred C57BL ; Phenanthrenes ; pharmacology ; Signal Transduction ; Spleen ; cytology ; drug effects ; Suppressor of Cytokine Signaling 1 Protein ; metabolism ; Suppressor of Cytokine Signaling 3 Protein ; metabolism ; T-Lymphocytes, Regulatory ; cytology ; Th17 Cells ; cytology

OBJECTIVETo investigate the effect of DNA methyhransferase l (DNMT1) gene silencing on methylation of suppressor of cytokine signaling (SOCS-1) in multiple myeloma RPMI 8226 cells.

METHODSRecombinant plasmid pshRNA-DNMTl was transfected into multiple myeloma RPMI 8226 cells by lipofectamine 2000. RT-PCR and Western blot were used to detect the mRNA and protein expression of DNMTl in RPMI 8226 cells respectively before and after transfection. Methylation-specific polymerase chain reaction was used to detect the methylation level change of SOCS-1 gene in RPMI8226 cells transfected.

RESULTSDNMTl targeted short hairpin RNA(shRNA) was successfully inserted into the plasmid vector pshRNA. RT-PCR results showed that the relative mRNA expression level of DNMTI gene in RPMI 8226 cells transfected with pshRNA was 0.176±0.004 which was significantly lower than that in cells transfected by empty vector (0.956±0.033, P<0.01). Western blot analysis showed that the relative expression level of DNMT1 protein of RPMI 8226 cells transfected by pshRNA was 0.065±0.014, which was significantly lower than that in transfected cells by empty vector(0.415±0.027) (P<0.05). These results indicated that the recombinant plasmid pshRNA could effectively knock down the expression of DNMT1 gene in RPMI 8226 cells. Methylation analysis showed that the methylation level of SOCS-1 gene was obviously reduced after transfection.

CONCLUSIONDNMT1 gene in RPMI 8226 cell can be silenced by shRNA. DNMT1 gene silencing can significantly induce SOCS-1 gene hypomethylation, which indicates that DNMT1 may play an important role in the process of SOCS-1 hypermethylation.

Cell Line, Tumor ; DNA Methylation ; Gene Silencing ; Genetic Vectors ; Humans ; Multiple Myeloma ; RNA, Messenger ; RNA, Small Interfering ; Repressor Proteins ; Suppressor of Cytokine Signaling 1 Protein ; Suppressor of Cytokine Signaling Proteins ; Transfection

BACKGROUNDIdiopathic pulmonary fibrosis (IPF) is a progressive diffuse parenchymal disease with a poor prognosis. A variety of cytokines and chemokines are involved in its pathophysiology. The aim of this study was to evaluate the clinical features in IPF patients with the expression of suppressor of cytokine signaling 1 (SOCS-1), which acts as a negative regulator of cytokine signaling.

METHODSIPF patients (n = 20) and healthy controls (n = 16) were included in this study. The expression of SOCS-1 was analyzed in peripheral blood mononuclear cells (PBMC) of subjects using RT-PCR. Interleukin 4 (IL-4), transforming growth factor β1 (TGF-β1) and type I collagen expression were also analyzed in each individual using enzyme-linked immunosorbent assay (ELISA). The clinical characteristics of IPF patients were delineated. These results were analyzed by SPSS13.0 statistics software.

RESULTSSOCS-1 mRNA expression was significantly decreased in the PBMC of IPF patients compared with healthy controls; serum levels of IL-4 and TGF-β1 were higher in IPF patients. The patients with lower expression of SOCS-1 developed lower percentage of forced vital capacity (FVC%) and DLCO/VA. A patients' SOCS-1 mRNA level was negatively correlated with serum levels of IL-4, and negatively correlated with their high-resolution computed tomography (HRCT) scores.

CONCLUSIONSSOCS-1 mRNA can be detected in PBMC, and it is down-regulated in IPF patients. The expression of SOCS-1 is associated with the severity of IPF patients' symptoms, so it might be the predictor of disease severity. SOCS-1 might play an important role in IPF by reducing the expression of the T helper type 2 (Th2) cell-related cytokine IL-4.

Adult ; Aged ; Aged, 80 and over ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Idiopathic Pulmonary Fibrosis ; metabolism ; Interleukin-4 ; metabolism ; Leukocytes, Mononuclear ; metabolism ; Male ; Middle Aged ; Suppressor of Cytokine Signaling 1 Protein ; Suppressor of Cytokine Signaling Proteins ; genetics ; metabolism ; Transforming Growth Factor beta1 ; metabolism

OBJECTIVETo investigate the regulation trend of Jinxin Oral Liquid (JXOL) on the expression of negative regulatory factor of TLR3 signaling pathway SOCS1 in the lung tissue of RSV infected BALB/c mice at different time points.

METHODSTotally 75 BALB/c mice were randomly divided into 5 groups, i.e., the normal control group, the model group, the ribavirin group, the high dose JXOL group, and the equivalent dose JXOL group, 15 in each group. Each group had 3 intervention ways (I, II, and III) with 5 mice treated in each group. BALB/c mice were nasally infected with respiratory syncytial virus (RSV), and treated by different intervention ways. After intervention, mice were killed and their lung tissues were sampled, mRNA expression levels of RSV-M, SOCS1, and IFN-β were detected by Real time PCR. The expression of SOCSl at the protein level was detected by Western blot.

RESULTSCompared with the normal control group, the mRNA expression level of SOCS1 and IFN-β, and the protein expression level of SOCS1 increased significantly in the model group intervened by intervention I and II (all P < 0.01), but the mRNA expression level of IFN-β decreased significantly in model group intervened by intervention III (P < 0.01). Compared with the model group, the mRNA expression level of RSV-M all significantly decreased in the high dose JXOL group and the equivalent dose JXOL group intervened by 3 intervention ways (all P < 0.01). The mRNA expression level of SOCS1 significantly decreased in the high dose JXOL group intervened by intervention I and III and the equivalent dose JXOL group intervened by 3 intervention ways (all P < 0.01). The mRNA expression level of IFN-β significantly decreased in the high dose JXOL group intervened by intervention I and II and the equivalent dose JXOL group intervened by intervention I (all P < 0.01), while it significantly increased in the high dose JXOL group intervened by intervention III and the equivalent dose JXOL group intervened by intervention III (all P < 0.01). The protein expression level of SOCS1 significantly decreased in the high dose JXOL group intervened by intervention I and the equivalent dose JXOL group intervened by 3 intervention ways (all P < 0.01), while it significantly increased in the high dose JXOL group intervened by intervention III (all P < 0.01). Compared with the high dose JXOL group, the mRNA expression level of RSV-M decreased significantly in the equivalent dose JXOL group intervened by intervention I and II (P < 0.01). The mRNA expression level of SOCS1 and IFN-β decreased significantly in the equivalent dose JXOL group intervened by intervention I (P < 0.01), but the mRNA expression level of IFN-β increased significantly in the equivalent dose JXOL group intervened by intervention II and III (all P < 0.01). The protein expression level of SOCS1 decreased significantly in the equivalent dose JXOL group intervened by 3 intervention ways (all P < 0.01).

CONCLUSIONSJXOL could inhibit the expression of SOCS1 in the lung tissue of RSV infected BALB/c mice at different time points. Its regulatory effect might be associated with promoting the expression of interferon type I and further fighting against RSV.

Animals ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Lung ; metabolism ; Mice ; Mice, Inbred BALB C ; RNA, Messenger ; Respiratory Syncytial Virus Infections ; drug therapy ; metabolism ; Respiratory Syncytial Viruses ; Ribavirin ; Signal Transduction ; Suppressor of Cytokine Signaling 1 Protein ; Suppressor of Cytokine Signaling Proteins ; metabolism ; Toll-Like Receptor 3 ; metabolism

OBJECTIVE: To investigate the expression pattern of adapter protein with a Src-homology 2 domain (SH2B1), the suppressor of cytokine signaling-3 (SOCS3), protein-tyrosine phosphatase 1B (PTP1B) and neturopetide Y (NPY) in obese and normal mice hypothalamus and its relation with serum leptin and insulin levels. METHODS: The obesity animal model was prepared with healthy C57/bl6 mice. Lee's index and Homeostasis model assessment-insulin resistance (HOMA-IR) were calculated. The mRNA levels of SH2B1, SOCS3, PTP1B and NPY were measured by fluorescent quantitation RT-PCR. The SH2B1 and NPY protein expressions were detected by Western blot. RESULTS: Compared with the normal mice of the same age, SH2B1 mRNA expression in the obese mice hypothalamus decreased. SOCS3 and PTP1B mRNA expression increased. Western blot showed that SH2B1 protein expression decreased, while NPY protein expression increased in the obese mice. Linear correlation analysis showed that the serum leptin and fasting insulin levels were negatively correlated with SH2B1mRNA expression and positively correlated with SOCS3 and PTP1B mRNA expression. CONCLUSION SH2B1, SOCS3, PTP1B and NPY are key factors for obesity development.
Adaptor Proteins, Signal Transducing ; metabolism ; Animals ; Hypothalamus ; metabolism ; Insulin ; blood ; Insulin Resistance ; Leptin ; blood ; Mice ; Mice, Inbred C57BL ; Neuropeptide Y ; metabolism ; Obesity ; metabolism ; Protein Tyrosine Phosphatase, Non-Receptor Type 1 ; metabolism ; RNA, Messenger ; Suppressor of Cytokine Signaling 3 Protein ; Suppressor of Cytokine Signaling Proteins ; metabolism

This study was purposed to investigate the effect of mutation and single nucleotide polymorphism (SNP) of suppressor of cytokine signaling (SOCS) on the typical myeloproliferative neoplasms (MPN) and its mechanism. The mutation and SNP of SOCS1, SOCS2, SOCS3 genes in 100 MPN patients were detected by RT-PCR and direct sequencing. The results showed that among 100 cases there were 21 cases with A→C polymorphism in the 63th site nucleotide of the 15 SOCS3 exon (SNP library no reported), 18 cases with A→C polymorphism in the 1779th site nucleotide of the 15 SOCS3 exon, 49 cases with A→G polymorphism in the 2249th site nucleotide of the 15 SOCS3 exon (SNP library no reported), 39 cases with T→C polymorphism in the 2366th site nucleotide of the 15 SOCS3 exon (SNP library no reported), 9 cases with T→C polymorphism in the exon of 15 SOCS2 gene (SNP library no reported). SOCS3 SNP was found in patients with significantly advanced age at diagnosis, the leukocyte count and platelet level were higher than those in patients with wild type, JAK2V617 mutations was found in 87.65% SOCS3 SNP. It is concluded that the SOCS may be an important target for anticancer therapy, the single nucleotide polymorphism of SOCS may involve to pathogenesis of MPN.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Exons ; Female ; Humans ; Male ; Middle Aged ; Mutation ; Myeloproliferative Disorders ; genetics ; Polymorphism, Single Nucleotide ; Suppressor of Cytokine Signaling 1 Protein ; Suppressor of Cytokine Signaling 3 Protein ; Suppressor of Cytokine Signaling Proteins ; genetics ; Young Adult

OBJECTIVETo investigate the effect of hepatitis B virus-encoded X protein (HBx) on the expression of host-encoded suppressor of cytokine signaling-1 (SOCS-1) and to explore the possibility of an underlying mechanism involving modulation of CpG island methylation in the SOCS-1 gene promoter.

METHODSThe immortalized human derived non-tumor liver cell line QSG7701 was transfected with a recombinant HBx plasmid (pcDNA-X) or an empty vector control plasmid (pcDNA3.0) and stably transfected clones were selected by G418 resistance screening. Untransfected cells served as negative controls. Expression of SOCS-1 mRNA and protein was detected by real-time quantitative PCR and western blotting. The methylation status of SOCS-1 was detected by methylation-specific PCR (MSP). The significance of intergroup differences was analyzed by one-way ANOVA or pairwise comparison with post-hoc LSD test.

RESULTSSOCS-1 mRNA level was significantly lower in the pcDNA-X/QSG7701 cells compared to that in the pcDNA3.0/QSG7701 and untransfected cells (0.3249+/-0.0536 vs. 1.0543+/-0.1937 and 1.00; F = 19.6, P = 0.042). SOCS-1 protein level was similarly lower in the pcDNA-X/QSG7701 cells (0.1496+/-0.0106 vs. 0.1984+/-0.0438 and 0.2152+/-0.0816; F = 19.4, P = 0.048). The SOCS-1 promoter region showed methylation only in the pcDNA-X/QSG7701 cells.

CONCLUSIONHBx-expressing human hepatocytes have down-regulated SOCS-1 expression, both at the mRNA and protein levels, and this effect corresponds to increased methylation in the SOCS-1 promoter region harboring CpG islands.

Cell Line ; CpG Islands ; DNA Methylation ; Humans ; Plasmids ; Promoter Regions, Genetic ; RNA, Messenger ; genetics ; Suppressor of Cytokine Signaling 1 Protein ; Suppressor of Cytokine Signaling Proteins ; metabolism ; Trans-Activators ; genetics ; metabolism ; Transfection

BACKGROUNDSuppressor of cytokine signaling (SOCS) proteins are inhibitors of cytokine signaling pathway involved in negative feedback loops. Although SOCS1 is an important intracellular suppressor of apoptosis in a variety of cell types, its role in cytokine-induced pancreatic β-cell apoptosis remains unclear. The present study investigated potential effects of SOCS1 on the cytokine-induced pancreatic β-cell apoptosis.

METHODSAfter successfully transfected with SOCS1/pEGFP-C1 or pEGFP-C1 plasmids to overexpress SOCS1, RINm5F (rat insulinoma cell line) cells were exposed to cytokines, interferon (IFN)-γ alone, IFN-γ+interleukin (IL)-1β, IFN-β+IL-1β+tumor necrosis factor (TNF)-α respectively. Pancreatic β-cell apoptosis was assessed by using MTT, FACS, and caspase-3 activity assays. Protein phosphorylation of Janus kinase 2 (JAK2) and signal transducers and activators of transcription 1 (STAT1) were verified by Western blotting and mRNA expression of inducible nitric oxide synthase (iNOS), NF-κB and Fas were analyzed by RT-PCR.

RESULTSOverexpression of SOCS1 in RINm5F cells was shown to attenuate IFN-γ alone, IFN-γ+IL-1β and IFN-γ+TNF-α+IL-1β mediated apoptosis. Phosphorylation of JAK2 and STAT1 significantly decreased in RINm5F cells which overexpressed SOCS1 protein. Overexpression of SOCS1 significantly suppressed cytokine-induced iNOS mRNA levels.

CONCLUSIONOverexpression of SOCS1 protects pancreatic islets from cytokine-induced cell apoptosis via the JAK2/STAT1 pathway.

Animals ; Apoptosis ; drug effects ; genetics ; Blotting, Western ; Cell Line ; Cytokines ; pharmacology ; Interferon-gamma ; pharmacology ; Interleukin-1 ; pharmacology ; Islets of Langerhans ; cytology ; drug effects ; Janus Kinase 2 ; metabolism ; Phosphorylation ; drug effects ; Rats ; Reverse Transcriptase Polymerase Chain Reaction ; STAT1 Transcription Factor ; genetics ; metabolism ; Signal Transduction ; drug effects ; Suppressor of Cytokine Signaling 1 Protein ; Suppressor of Cytokine Signaling Proteins ; genetics ; metabolism ; Tumor Necrosis Factor-alpha ; pharmacology

OBJECTIVESuppressors of cytokine signaling (SOCS) have been shown to play an important role in regulating cytokines, such as intracellular interferon (IFN) and interleukin (IL), in the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway. At present, the association between SOCS and asthma is still under study. The aim of this study is to explore the relationship of SOCS-1 and SOCS-3 mRNA expression in peripheral blood mononuclear cells (PBMCs) with the intracellular IFN-'/IL-4 ratio in CD4+ T cells and specific IgE (sIgE) level in children with asthma.

METHODSBMCs were collected from 44 children with allergic asthma (4-14 years) and 30 healthy children. The intracellular IFN-'/IL-4 ratio in CD4+ T cells was measured by flow cytometry. Total RNAs were extracted from the PBMCs and SOCS-1 and SOCS-3 mRNA expression was measured by SYBR Green I quantitative RT-PCR.

RESULTSCompared with the healthy children, children with allergic asthma showed a lower level of intracellular IFN-' in peripheral blood [(15.7±2.0)% vs (19.1±2.7)%] and IFN-'/IL-4 ratio (3.4±1.5 vs 4.8±2.9) and higher SOCS-1 mRNA expression (-Ct, 11.1±1.9 vs 12.6±2.8). There was a negative relationship between SOCS-1 mRNA expression and the percentage of IFN-'-producing CD4+ T cells in peripheral blood in both asthmatic and healthy children (P<0.05). No correlation was found between SOCS-1 and SOCS-3 expression and sIgE level.

CONCLUSIONSChildren with allergic asthma have elevated levels of SOCS-1 mRNA in PBMCs, which is associated with Th2-skewed immune response.

Adolescent ; Asthma ; immunology ; Child ; Child, Preschool ; Cytokines ; genetics ; Female ; Gene Expression Regulation ; Humans ; Interferon-gamma ; genetics ; Interleukin-4 ; genetics ; Male ; RNA, Messenger ; analysis ; Signal Transduction ; Suppressor of Cytokine Signaling 1 Protein ; Suppressor of Cytokine Signaling 3 Protein ; Suppressor of Cytokine Signaling Proteins ; genetics ; Th1 Cells ; immunology ; Th2 Cells ; immunology