1.Role and Clinical Significance of Myeloid Differentiation Protein-2 in Endotoxin Signal Transduction
xi-hua, YUAN ; chang-hui, CHEN
Journal of Applied Clinical Pediatrics 1992;0(06):-
Myeloid differentiation protein-2(MD-2)can separately and simultaneously bind lipopolysaccharide(LPS)and toll-like receptor 4(TLR4)has been shown to play critical roles in mediated recognition responses to LPS by TLR4 and signal transduction induced by LPS.MD-2 can be bound by LPS,not TLR4.The cells have no responsiveness or weak responsiveness to LPS without MD-2.MD-2 can be secreted into blood plasma,formed soluble MD-2 and remotely regulated cells that contained TLR4 without MD-2.MD-2 has been shown to play important roles in endotoxin signal transduction.MD-2 is a small molecular,short nucleic acid fragment,easily regulated should become a new potential anti-inflammatory target.
2.Effects of fibrogenetic growth factors on migration of hepatic stellate cells
Chang-Qing YANG ; Yi-Zhong CHANG ; Xi-Mei CHEN ;
Chinese Journal of Digestion 2001;0(12):-
Objective To investigate the impact of alterations within the space of Disse micro- environment on the migration of hepatic stellate cells(HSC) during the process of liver fibrosis,and to ex plore the novel mechanism of liver fibrosis from the view of cell migration.Methods A modified in vitro Boyden chamber system to partially mimic in vivo microenvironment of Disse space of normal and liver fibrosis was employed.The effects of fibrogenetic growth factors on the migration of HSC in liver fibrosis were observed via cell migration and cell proliferation experiments.Results Enhanced platelet-derived growth factor(PDGF)-BB,transforming growth factor(TGF)-?1 and/or epithelial growth factor(EGF) in liver fibrosis resulted in an increase in migratory capacity of activated HSC.The enhanced migration of HSCs induced by PDGF-BB was partially associated with their increased proliferation,while,TGF-?1 or EGF-induced migration was proliferation independent.The elevation of basic fibroblast growth factor (bFGF) or vascular endothelial growth factor(VEGF)during liver fibrosis had no effect on the migration of HSCs.Conclusions The study provides valuable insights into the role of space of Disse microenvironment in regulating HSC migratory behavior.TGF-?1,PDGF-BB and EGF,which increased in liver fibrosis, could induce the migration of activated HSC.However,bFGF or VEGF has no such kind of effect,al- though they also increased during liver fibrosis.
4.Application of Plasma Exchange Therapy on Critical Diseases in Children
xi-yu, HE ; ping, CHANG ; hui, CHEN ; zhi-chun, FENG
Journal of Applied Clinical Pediatrics 2006;0(18):-
Objective To explore continuous renal replacement therapy(CRRT) machine for plasma exchange in critical disease in children.Methods Retrospective study of 8 patients(8 month to 14 years,mean 5.7 years) and 32 plasma exchange treatments,after(adowble) lumen catheter inserted into the subclayian venous,using the Baxter BM25 machine with commercially available plasma filters.Results Five patients(3 ABO-incompatibility in bone marrow transplantation,1 thrombotic thrombocytopaenic purpura TTP,1 sepsis) gained full recovery.One systemic lupus erythematosus(SLE) and 1 sepsis experienced moderate improvement while 1 case of acute disseminated encephalomyelitis failed PE treatment.The average total exchange volume was 80-100 mL/kg,achieved at a blood flow rate of 5-10 mL/(kg?min) and a turnover rate of 60-120 mL/(kg?h) over a 3-hours duration.Thirty-one PE treatments were finished smoothly,one of which experienced the serious complication involving plasma filter.Conclusion Plasma exchange therapy is a safe and effective procedure for severe autoimmune abnormalities and pathogen removal in children.
5.Protective effects of IGF-1 on cell injuries and tau hyperphosphorylation induced by okadaic acid.
Zhou CHEN ; Bin CHEN ; Chang-xi YU
Chinese Journal of Applied Physiology 2010;26(2):202-205
OBJECTIVETo investigate the effects of insulin-like growth factor-1 (IGF-1) on cell injuries and tau hyperphosphorylation induced by okadaic acid (OA).
METHODSThe experimental groups were designed as follows: (1) SH-SY5Y culture (control group); (2) SH-SY5Y exposed to 40 nmol/L OA for 24 hours (OA group); (3) SH-SY5Y exposed to OA for 24 hours in the presence of 2 hour pretreatment with 100, 200 and 400 ng/ml IGF-1 (IGF-1 pretreatment groups). The changes of cell morphology were observed by inverted microscope. The viability of cells was detected by MTT. The injuries of cells were examined by Hoechst 33258 staining and the activity of caspase-3. Western-blot was applied to determine the expression of phosphorylation of tau protein.
RESULTSIn IGF-1 pretreatment group, the cell morphology was improved, the viability of cells was increased, and caspase-3 activation and hyperphosphorylation of tau (Ser396) were reduced.
CONCLUSIONIGF-1 can protect the SH-SY5Y cells from cell injuries induced by OA by inhibiting tau hyperphosphorylation.
Cell Line, Tumor ; Humans ; Insulin-Like Growth Factor I ; pharmacology ; Neuroblastoma ; pathology ; Neuroprotective Agents ; pharmacology ; Okadaic Acid ; antagonists & inhibitors ; toxicity ; Phosphorylation ; drug effects ; tau Proteins ; chemistry
6.The hepatic stellate cells protection for homotransplanted islet cells
Xi CHEN ; Yao WEI ; Qiang ZHANG ; Chang SU ; Zhengyun ZHANG ; Mingjun ZHANG ; Guangwen ZHOU
Chinese Journal of General Surgery 2010;25(5):401-404
Objective To analyze the protection supplied by HSCs in vivo after islet cells homotransplantation. Method Diabetic mice were randomly divided into three groups as diabetic group,islet-transplant group and co-transplant group. 300 islets alone or mixed with HSCs were transplanted under the capsule of the kidney of the diabetic recipients respectively. Blood glucose and the length of normal blood glucose level were recorded and we collected the blood and tissue of islet graft 7 days after transplantation in each group. Blood concentration of TGF-β, TNF-α, IL-1β and IFN-γ were detected by ELISA. The infiltration of lymphocytes was observed by HE staining and immunohistochemieal examination.Result Co-transplant group had a prolonged islet allograft survival for (23.75 ± 8. 96) days, compared with the islet alone of (11.9 ± 6. 92) days. Blood concentration of TGF-β in co-transplant group was (2292.31 ± 5.87) pg/ml, significantly higher than those in simple transplant group (1246.55 ±38.91) pg/ml(P <0.05), there was no differentence in the two groups for TNF-α,IL-1β and IFN-γ.Conclusion HSCs may prolong the islet graft survival by expressing higher level of TGF-β and form a capsule around the graft.
7.The protection of xenotransplanted murine pancreatic islets by induced expression of heme oxygenase-1
Yao WEI ; Xi CHEN ; Zhengjun ZHANG ; Chang SU ; Mingjun ZHANG ; Weiqiong GU ; Xiaoying LI ; Guangwen ZHOU
Chinese Journal of General Surgery 2009;24(12):1019-1023
Objectlve To explore the mechanism of the protection in high expression of HO-1 induced by CoPP on murine islet xenografts. Method An islet transplantation of a SD rat-to-C57 BL/6 mouse model was established.Mice were randomized into five groups i.e.control,CoPP-induction in vivo,CoPP+ZnPP in vivo.CoPP-induction in vitro and CoPP+ZnPP in vitro and the islet xenografts were transplanted into the subrenal capsule.Normoglycemia time was recorded and insulin-releasing test was performed.IL-10、TNF-α、IL-1β and INF-γ in serum and their cytokine mRNA and HO-1 in xenografts were measured by RT-PCR and Western-blotting.The pathological examination was done to observe the lymphocyte infiltration. Results There Was significant difference in the normoglycemia time between CoPP-induction in vivo and in vitro and other three groups.The results of insulin-releasing stimulated by low level glucose were identical among groups,but that of insulin-releasing stimulated by high-glucose in in vivo group were the hiishest as in CoPP-induction in vivo and in vitro and control group were 187.68 ±19.93、137.22±11.73,91.25±12.64 μIU·ml~(-1)·10islets~(-1)·45 min~(-1),(P<0.05).The IL-10 in serum in CoPP-induction in vivo and in vitro(in vivo:72.97±9.74 pg/ml;in vitro:70.84±3.56 pg/ml)was significantly hisher than other three groups(control:30.57±3.93 pg/ml;CoPP+ZnPP in vivo:39.78±3.00 pg/ml;CoPP+ZnPP in vitro:35.42±4.30 pg/ml).The expression tendency of IL-10 mRNA was similar to that of insulin secretion.There was no significant difieFence in TNF-α、IL-1β and INF-γ.The expression of HO-1 by PCR and Western-blot analysis in CoPP-induction in vivo and vitro was higher than other three groups.The pathological examination showed that fewer lymphocytes infiltrated into the islet xenografts from CoPP-treated in comparison with xenografts from other three groups. Conclusion HO-1 could improve the survival of islet xenograft:the induetion of HO-1 expression in vivo was much mole efficient than in vitro.The CoPP-induction could be related to immune modulation of IL-10.
8.Protective effect of cobalt protoporphyrin-induced the strong expression of heme oxygenase-1 on islet xenotransplant
Zhengyun ZHANG ; Xi CHEN ; Chang SU ; Weiqiong GU ; Hongwei LI ; Guangwen ZHOU
Chinese Journal of Organ Transplantation 2008;29(6):343-345
Objective To analyze the dose-effect relationship between cobalt protoporphyrin (CoPP) and heme oxygenase-1 (HO-1) expression in islets and to investigate the protective effect of strongly expression of HO-1 in islet xenotransplantation. Methods Donor islets isolated and purified from SD rats were randomly divided into 5 groups and incubated with different doses of CoPP for 24 h.Group A: 0 mmol/L; Group B: 5 mmol/L; Group C: 25 mmol/L; Group D: 50 mmol/L; Group E:75 mmol/L. The expression of HO-1 mRNA and protein in islets was detected by RT-PCR and Western blot respectively. Glucose of low and high concentrations was added to islets in vitro to test insulin-releasing function. The optimal dose of CoPP which could induce the strongest HO-1 expression was chosen according to the results. Recipients were randomly divided into 2 groups. Control group received untreated xeno-islets, and the experimental group received islets incubated with optimal CoPP close in vitro. Glycemia and rejection were observed after transplantation daily. Results The expression of HO-1 mRNA and protein in xeno-islets of group D was significantly higher than in other groups (P<0.05). After stimulation of glucose, the insulin concentration in group D was significantly higher than in other groups (P<0.05). The optimal dose of CoPP which could induce the strongest HO-1 expression was 50 mmol/L. The time for normoglyeemia in experimental group was (14.63±1.19) days, significantly longer than that in control group (9.88±2.17)days (P<0.01). Conclusion The strongest expression of HO-1 induced by CoPP in vitro promotes the glucose-stimulated insulin secretion of islets and prolonged the survival of xeno-islet grafts by protecting them from rejection.
9.CoPP induces Ho-1 upregulation in rat islet cells
Chang SU ; Zhengyun ZHANG ; Xi CHEN ; Weiqiong GU ; Mingjun ZHANG ; Qiang ZHANG ; Guangwen ZHOU ; Hongwei LI
Chinese Journal of General Surgery 2008;23(5):372-375
Objective To investigate the effects of peritoneal injection of cobaltic protoporphyrin Ⅸ chloride(CoPP)to induce heme oxygenase-1(Ho-1)upregulation in rat islet cells.Mthods Forty rats were divided into 5 groups by management 24 h before islets isolation:group A received inlzaporitoneal injection with 2.5 ms/ks CoPP,group B with 5 ms/ks CoPP,group C with 7.5 ms/kg CoPP,and group D with 10 mg/kg CoPP.In control group NS was used instead.A modified Goth approach was used for islet isolation.the yield and purity of the islets were assessed.The expression of Ho-1 mRNA and protein were detected by real time-PCR and Western blotting respectively.Islet function was tested by glucose stimulation test.Result Severe damage was found in tlle rats in group C and D.There was no difference in islet yield and purity for group A、B、C and control(P>0.05).Group B had the highest Ho-1 mRNA and protein expression among the 4 groups.Though there was no difference in insulin secretion by low glucose challenge for group A、B and control's islets(P>0.05),when challenged by hish level of glucose,significant deviation was observed.The imulin secretion level was(172.37±16.4)、(187.68±19.93)and(91.25±Conclusion Peritoneal iajection of 5 mg/kg CoPP can significantly enhance the expression of Ho-1 mRNA and protein in tat islet safely and enhance the function of islet when challenged by hish concentration of glucose.