Effects of starvation, diabetesand obese conditions on mouse hepatic SOCS2 gene expression / 基础医学与临床

Objective To determine the expression levels of SOCS2 in the mouse livers under starvation, diabetes and obese conditions and to study the effect of SOCS2 on gluconeogenesis.Methods Animals were divided into 3 groups: C57BL/6J mice, the control group was fed ad libtum and the experimental group was fasted for 24 h.Diabetes model db/db and the control db/m mice were fed ad libitum.Obese model ob/ob and the control C57BL/6J mice were fed ad libitum.All the mice above were sacrificed and total RNA was isolated from mouse livers and reverse transcribed to cDNA.The expression of SOCS2 and gluconeogenesis genes in the mouse livers in the 3 groups above were detected by real-time quantitative PCR.SOCS2 was overexpressed in the primary C57BL/6J mouse hepatocytes by the adenovirus system.The effect of SOCS2 on glucose production was measured by glucose output assay.Results C57BL/6J mouse hepatic SOCS2 expression was suppressed by starvation status.The expression of SOCS2 was decreased in the livers of db/db and ob/ob mice.In contrast, the key regulators of gluconeogenesis, PGC-1α, PEPCK and G6Pase exhibited the opposite expression pattern as SOCS2 in the livers underidentical starvation, diabetes and obese conditions.The protein was Mr 23 000 and glucose production was inhibited after SOCS2 being overexpressed in the primary C57BL/6J mouse hepatocytes by adenovirus system.Conclusions SOCS2 may inhibit gluconeogenesis in the C57BL/6J mouse primary hepatocytes, and SOCS2 may be a potential target for the treatment of type Ⅱ diabetes.

Função das células dendríticas durante a infecção experimental por Trypanosoma cruzi: papel de SOCS2 / Dendritic cell function during experimental Trypanosoma cruzi infection: role of SOCS2

A infecção por Trypanosoma cruzi (T. cruzi), causador da doença de Chagas, induz uma reação inflamatória e a eficiência da resposta imune (RI) do hospedeiro é importante para que a infecção persista ou seja eliminada. A expressão de SOCS2 (Supressor de Sinalização de Citocinas)2, uma proteína intracelular, é parcialmente mediada por lipoxinas (LXA4, eicosanoide anti-inflamatório) em células dendríticas (DCs), a principal célula apresentadora de antígeno (APC). Demonstramos que SOCS2 é fundamental durante a infecção por T. cruzi modulando a geração/expansão de células Th1, Treg e de memória e no controle da função cardíaca. No presente trabalho, nós pesquisamos o papel de SOCS2 na função de DCs e na indução/manutenção da RI durante a infecção experimental por T. cruzi. Camundongos CD11cDTR transgênicos (depleção de DCs), selvagens (WT) e deficientes de SOCS2 (knockout/KO) foram infectados com a cepa Y de T. cruzi. Nossos resultados demonstraram um aumento da parasitemia nos animais depletados de DCs, ressaltando que DCs são cruciais no controle da infecção por T. cruzi. Durante a RI inata a ausência de SOCS2 resultou na redução da frequência de DCs produtoras de citocinas inflamatórias (IL-12 e TNF-α), mas não de IL-10, sem alterar a expressão dos receptores do tipo Toll (TLR2 e TLR4) e de MHC II. Em contraste, uma diminuição na expressão da molécula co-estimuladora CD80 foi observada em DCs deficientes de SOCS2. Durante a RI adaptativa a ausência de SOCS2 em DCs resultou no aumento dos níveis de expressão de TLR2 e TLR4 e na redução da frequência de DCs expressando MHCII. A transferência adotiva de DCs deficientes de SOCS2 ocasionou aumento da parasitemia e mudanças do perfil da RI frente a infecção por T. cruzi, principalmente: i) reduzindo a frequência de células NK produtoras de IFN-γ e de IL17; ii) diminuindo a frequência de células T CD8 produtoras de IFN-γ e de T CD4 produtoras de IL-17, apesar de aumentar células T CD4 produtoras de IFN-γ; ausência de SOCS2 em DCs também resultou em redução de células produtoras de IL-10, como T CD4 e CD19, além das células Treg. Nossos resultados também demonstraram que SOCS2 é importante na modulação da apoptose durante a infecção por T. cruzi, onde a deficiência de SOCS2 leva a um aumento da apoptose de neutrófilos durante a RI inata, de macrófagos nas RI inata e adaptativa e de linfócitos na RI adaptativa. Nossos resultados in vitro demonstraram um aumento de caspase 3 total e clivada em neutrófilos deficientes em SOCS2. Em conjunto, nossos resultados demonstraram que SOCS2 é crucial na modulação das funções de DCs durante a geração e regulação da RI inata e adaptativa durante a infecção por T. cruzi.

The infection by Trypanosoma cruzi (T. cruzi), which causes Chagas' disease, induces an inflammatory reaction and the efficacy of the host immune response (IR) is important to persist or eliminate the infection. SOCS2 (supressor of cytokine signaling)2 expression, an intracellular protein, is partially mediated by lipoxins (LXA4, anti-inflammatory eicosanoid) in dendritic cells (DCs), the main antigen-presenting cell (APC). We demonstrated that SOCS2 is fundamental during T. cruzi infection by modulating the generation/expansion of Th1, Treg and memory cells and in the control of heart function. In the present work, we investigated the role of SOCS2 in DCs function and induction/maintenance of IR during experimental T. cruzi infection. CD11cDTR transgenic mice (DCs depletion), wild type (WT) and SOCS2 (knockout/KO) were infected with Y strain of T. cruzi. Our results demonstrated an increased parasitemia in depleted DCs animals, emphasizing that DCs are crucial in control of T. cruzi infection. During innate IR, absence of SOCS2 resulted in decreased frequency of inflammatory cytokines (IL-12 and TNF-α), but not IL-10 by DCs, without change the Tolllike receptor expression (TLR2 and TLR4) and MHCII. In contrast, a decreased expression of CD80 costimulatory molecule was observed in SOCS2 deficient DCs. During adaptive IR, absence of SOCS2 in DCs resulted in increased levels of TLR2 and TLR4 expression and reduced frequency of DCs expressing MHCII. Adoptive transfer of SOCS2 deficient DCs caused increased parasitemia and changes in IR profile against T. cruzi infection, specifically: i) reducing the frequency of NK cells producing IFN-γ and IL-17; ii) reducing the frequency of CD8 T cells producing IFN-γ and CD4 T cells producing IL-17, despite increasing CD4 T cells producing IFN-γ; absence of SOCS2 in DCs also resulted in reduction of cells producing IL-10 such as CD4 and CD19, besides Treg cells. Our results also demonstrated that SOCS2 is important in apoptosis modulation during T. cruzi infection, where absence of SOCS2 leads to increased apoptosis in neutrophils during innate IR, macrophages in innate and adaptive IR and lymphocytes in adaptive IR. Our in vitro results demonstrated an increase in cleaved and total caspase 3 in SOCS2 deficient neutrophils. Together, our results demonstrated that SOCS2 is crucial in the modulation of DCs' function during generation/regulation of innate and adaptive IR during T. cruzi infection

Characterization of variation in the canine suppressor of cytokine signaling-2 (SOCS2) gene

Suppressor of cytokine signaling 2 (SOCS2) is a negative regulator of growth hormone signaling. The deletion of SOCS2 in mice results in a 30-50% increase in post-natal growth. In an effort to identify polymorphisms in the SOCS2 gene that may be associated with body size in dogs, we characterized the canine SOCS2 gene and analyzed its genetic diversity among small and large dog breeds. The study was carried out on a total of 520 dogs from 66 different breeds. Dogs were classified as large or small based on height and weight as determined by their respective American Kennel Club breed standards. The SH2 and SOCS domains of the canine SOCS2 gene were sequenced in 32 dogs from different breeds. Only one non-synonymous sequence variant (DQ415457:g.326G>T) was detected which corresponds to an amino acid change (Asp127Tyr). All samples were genotyped by PCR/RFLP and the allele frequencies were determined for each dog breed. The T allele was distributed primarily among European large dog breeds with a gene frequency ranging from 0.72 to 0.04. The nature of the nucleotide change and the effect on the protein together with the finding of a QTL related to body size in the same CFA15 region by other researchers suggest canine SOCS2 as a potential candidate gene for body size in dogs. Future studies will be needed to clarify the role of the 326G>T polymorphism and its interaction with genes like growth hormone and insulin-like growth factor 1

Mechanisms and Effect of Ginkgolide B on the Differentiation of Neuron Stem Cells / 中国康复理论与实践

@#Objective To observe the effect of Ginkgolide B of various consistency on the differentiation of neuron stem cells (NSCs).MethodsNSCs were cultured in differentiation medium containing Ginkgolide B of various consistency for 3 and 7 days, the neurites length and cell body area were measured by inverted phase-contrast micrograph, then neurofilament-200 (NF-200), glial fibrillary acidic protein (GFAP), adenomatus polyposis coli (CC-1) expression were detected and counted by fluorescence microscope. The suppressor of cytokine signaling-2 (SOCS2), inhibitor of DNA binding-2 (Id2) were alsoimmunostained. The percentage of positive cells were counted respectively.ResultsThe neurites length and cell body area in Ginkgolide B groups were obviously larger than that in the control group. The percentage of NF, GFAP positive cells in Ginkgolide B groups increased with dosage increasing of Ginkgolide B. Compared with the normal control group, the percentage of SOCS2 positive cells increased significantly ( P<0.01) and the percentage of Id2 positive cells decreased significantly ( P<0.01) in Ginkgolide B groups.ConclusionGinkgolide B can promote NSCs to differentiate into neuron and astrocyte, the percentage of astrocyte is increased with a dosage-dependent relationship with Ginkgolide B.