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Objective To explore the effects of long-term low-protein intake on nonspecific inflammatory responses in the liver and T lymphocytes in the spleen in middle-aged and older mice and underlying mechanisms.Methods Fourteen month-old female KM(Kunming)mice were randomly divided into the control group,the low-protein group,the high-protein group and the high-protein + rapamycin group.Additionally,Two month-old female KM mice served as the adult group and were fed regular chow.Animals in the high-protein + rapamycin group received injections of rapamycin intraperitoneally once every two days.Animals were sacrificed at the end of 3 months.Liver histology slices were prepared for the examination of pathological changes and detection of the expression of CD68 and mTOR(the mechanistic target of rapamycin).Spleen lymphocyte suspensions were prepared to count the percentages of CD4+ T and CD8+ T cells.Results Compared with the control group,the low-protein group and the high-protein-+-rapamycin group in histology slides showed regularly arranged hepatocytes,no obvious sinus hepaticus expansion and only mild time-related changes.Moreover,compared with the control group,the low-protein and high-protein + rapamycin groups were associated with increased percentages of CD4+T and CD8 + T cells in the spleen(all P＜ 0.05)and decreased expression of CD68 in the liver(P＜0.05),though the levels of mTOR were similar among the groups.Conclusions Long-term low-protein intake has beneficial effects in mitigating the reduction of T lymphocytes in the spleen and slowing age-related structural and nonspecific inflammatory changes in the liver,possibly through downregulation of the expression of the mTOR protein.
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Objective:To study the influence of proteasome inhibitor lactacystin (LAC) and carboplatin in proliferation and apoptosis of the human ovarian cancer SKOV3 cells in vitro ,and to clarify the mechanisms. Methods:The SKOV3 ovarian cancer cells were cultured in vitro ;0,2.5,5.0,10.0 and 20.0 μmol· L-1 LAC were used to intervent the SKOV3 cells for 48 h;5 μmol·L-1 LAC was used to intervent the SKOV3 cells for 0, 24,48,and 72 h;the SKOV3 cells were divided into control group (treated without medical intervention),LAC group (treated with 5 μmol · L-1 LAC), carboplatin group (treated with 10, 20, 40 and 80 μmol · L-1 carboplatin),LAC and carboplatin group (treated with 5 μmol· L-1 LAC and 10,20,40,and 80 μmol· L-1 carboplatin,respectively).MTT method and FCM were used to detect the inhibitory rates of proliferation and apoptotic rates of the SKOV3 cells in various groups.Results:The MTT test results showed that the proliferation of the SKOV3 cells were inhibited with the prolongation of time and increasing of LAC concentration;the half inhibitory concentration (IC50 )of LAC at 48 h was 5.36 μmol · L-1 ;compared with carboplatin group,the inhibitory rates of proliferation of SKOV3 cells in LAC and carboplatin groups were significantly increased (P <0.05).The IC50 of carboplatin was dropped from 58.08 μmol·L-1 to 18.37 μmol·L-1 .The FCM results showed that with the prolongation of treated time of LAC,the apoptotic rates of SKOV3 cells were increased;compared with carboplatin group and LAC group,the apoptotic rate of cells in LAC and carboplatin group was increased (P <0.05).Conclusion:LAC can inhibit the proliferation of the ovarian cancer SKOV3 cells and induce the apoptosis, and LAC can enhance the inhibitory effect of proliferation of carboplatin on the ovarian cancer SKOV3 cells.
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Objective To over-express human trefoil factor 2 (hTFF2) by Escherichia coli system and an-alyze its activities in promoting migration and anchorage-independent growth in SW480 colonic cancer cells. Meth-ods hTFF2 gene encoding mature peptide was obtained by RT-PCR, and the recombinant expression vector pET32a-hTFF2 was constructed. Then pET32a-hTFF2 was transformed into E. coli BL21-32a and TrxA-hTFF2 fu-sion protein was induced to over-express. The expressed product was isolated by Ni-NTA affinity chromatography, purified by dialysis and identified by Western blotting. The activities of the recombinant hTFF2 in promoting SW480 cells migration and anchorage-independent growth were analyzed by MicroChemotaxis Chamber migration assay and Soft-agar assay,respectively. Results The TrxA-hTFF2 fusion protein was expressed to 220 mg/L at high purity. In vitro model demonstrated that recombinant hTFF2 obviously enhanced SW480 cell migration activity and anchor-age-independent growth. Conclusion The recombinant hTFF2 can be expressed in E. coli with high production, purity and biological activities. And its roles in cell migration and anchorage-independent growth suggest that up-regulation of TFF2 in colonic cancer might be involved in cancer invasion and metastases.