Human dendritic cells transfected with MUC1 mRNA induce lethal effect of cytotoxic T-lymphocytes on non-small cell lung cancer in vitro

AIM：To investigate the specific anti-tumor effects of mature dendritic cells (DCs) transfected with amplified mucin 1 (MUC1) mRNA in vitro. METHODS：DCs separated and purified from the peripheral blood mononuclear cells were induced in vitro and then identified by flow cytometry. pcDNA3.1（+）-MUC1 plasmid was constructed and was able to transcribe MUC1 mRNA in vitro. The MUC1 mRNA was transfected into DCs by electroporation. MUC1-transfected DCs were used to induce T cells to be cytotoxic T-lymphocytes. Quantitative real-time PCR was performed to assess MUC1 mRNA expression in transfected DCs. The proliferation of T cells was examined by MTT assay. The proportion of CD8+ cells in the T cells was determined by flow cytometry and the specific cytotoxicity was measured by LDH assay. The secretion of IFN-γ was detected by ELISA. RESULTS：The marker gene expression in the DCs transfected with MUC1 mRNA was significantly increased compared with control group, peaking at 24 h. The transfection group showed the higher capacity to stimulate the proliferation of T cells compared with control group when the ratio of DCs to T cells was 1∶10. The proportion of CD8+ cells in transfection group was higher than that in control group. The lethal effect of special cytotoxic T-lymphocytes on target cells in transfection group was stronger than that in control group. The level of IFN-γ in the cell supernatant of transfection group was higher than that in control group. CONCLUSION：DCs plus MUC1 mRNA by electrical transfection induces specific anti-tumor effects, which provides an experiment evidence of using MUC1 as a target for immunotherapeutic strategy against non-small cell lung cancer.     

Effects of cannabinoids WIN and O-1602 on expression of HSPs in mice with colitis or acute pancreatitis

AIM: To investigate the effects of cannabinoids WIN55, 212-2 (WIN) and O-1602 on the expression of heat-shock proteins (HSPs), such as HSP27, HSP60 and HSP70, in the inflammatory tissues of mice with experimental colitis or acute pancreatitis (AP). METHODS: Mouse colitis was induced by feeding the C57/BL with 4% dextran sulfate sodium (DSS) for 7 d, and AP was induced by intraperitoneal injection of ceruline in the mice (50 μg/kg hourly, with a total of 6 times). The mice were intraperitoneally administered with WIN or O-1602 for the therapeutic evaluation by observing the following parameters: pathological changes of the tissues, plasma activity of amylase, plasma levels of IL-6 and cytokine-induced neutrophil chemoattractant-1 (CINC-1), and HSP expression in the colonic and pancreatic tissues. RESULTS: Compared with normal control mice, the colonic tissues from colitis mice and the pancreatic tissues from AP mice appeared obvious signs of inflammation and injury. The plasma levels of IL-6 and CINC-1 significantly increased in colitis mice and AP mice. In DSS group of colitis mice, HSP27 expression increased, but HSP60 and HSP70 were reduced in the colonic tissues. WIN showed anti-inflammatory effects on the pathological changes of colonic tissues and the plasma cytokine levels. WIN also improved the expression of HSP70 (P<0.05). In AP group, the expression of HSP27 and HSP70 in pancreatic tissues increased, and HSP60 decreased. O-1602 also showed some anti-inflammatory effects on the changes of the pathological tissues and the plasma parameters, but had no obvious effects on the HSP expression (P>0.05). CONCLUSION: The experimental colitis and acute pancreatitis in mice were induced by feeding DSS and injection of cerulein, respectively. The changes of HSP expression were different in the inflammatory tissues. WIN and O-1602 show anti-inflammatory effects and increase the expression of several HSPs to some extent.     

Effect of mesalazine on Th1, Th17 and Treg cells in mice with DSS-induced ulcerative colitis

AIM: To investigate the effect of mesalazine treatment on regulation of Th1, Th17 and Treg cells in mice with dextran sulfate sodium (DSS)-induced ulcerative colitis (UC). METHODS: The expression of IL-17, IFN-gamma and Foxp3 in the peripheral blood mononuclear cells (PBMC) and intestinal mucosa lamina propria mononuclear cells (LPMC) of DSS-induced UC mice was detected by flow cytometry analysis. The effect of mesalazine treatment on regulaiton of Th1, Th17 and Treg cells in the mice with DSS-induced ulcerative colitis was examined.RESULTS: The expression of IL-17, IFN-γ and Foxp3 on CD4+T cells were significantly higher in the PBMC of DSS-induced mice than those in control group. CD4+ IFN-γ+T cells and CD4+ Foxp3+T cells were higher in LPMC than those in control group, except CD4+IL-17+T cells. Moreover, the Th1, Th17 and Treg cells were higher in DSS group than those in control group in LPMC. However, only Tregs was higher in PBMC. Pre-treatment with mesalazine significantly decreased the number of Th17, Th1 and Treg cells of UC model mice both in PBMC and LPMC.CONCLUSION: The Th1, Th17 and Tregs cells in DSS-induced mice were significantly higher than those in control mice, suggesting that CD4+T cell subsets play an important role in the pathogenesis of UC. Mesalazine may play a role in the treatment of UC by regulating the Th1, Th17 and Tregs cells.     

Change of ICAM-1 expression in intestine tissue of mice induced by LPS and role of p38 MAPK in its expression

AIM: To study the change of intercellular adhesion molecule-1(ICAM-1) expression in intestine tissues of mice induced by LPS and regulatory effect of p38 mitogen-activated protein kinase(p38 MAPK) on ICAM-1 expression. METHODS: Protein and mRNA of ICAM-1 were measured using Western blotting and RT-PCR respectively in intestine tissue of BALB/c mice treated by lipopolysaccharide(LPS) or LPS plus SB203580, a specific inhibitor of p38 MAPK. RESULTS: Compared with control group, the expression of ICAM-1 protein and mRNA was increased significantly by LPS stimulation in dose- and time-dependent manner. ICAM-1 expression reached peak value at 12-36 h after LPS stimulation. 20.0 mg/kg of LPS could induce the maximum of ICAM-1 expression. Pretreatment of mice with SB203580 for 30 min could inhibit significantly LPS-induced expression of ICAM-1 protein and mRNA expression in mouse intestine tissues. CONCLUSIONS: These data highlight that LPS could up-regulate ICAM-1 protein and mRNA expression in intestine tissue of mice in dose- and time-dependent manner, and p38 MAPK signal pathway plays an important role in ICAM-1 expression induced by LPS. It suggests that inhibition of p38 MAPK might be a useful principle for the prevention and treatment of intestine damage of endotoxic shock.     

Protective effect of low dose of hydrocortisone on the liver in LPS attack rats

AIM:To study the effect of different dosage of hydrocortisone on the liver in lipopolysaccharides(LPS) attack rats.METHODS:The model of LPS attack rats was established,and different doses of hydrocortisone were given to the rats. ALT and AST levels in rat plasma were tested,and the histology of rat liver was observed by microscope. RESULTS:ALT and AST levels were high in LPS group and had significant difference compared with the normal control group. ALT level in low dose(LD) group had no significant difference compared with the normal control group. The pathological change in the liver was obviously congested in high dose(HD) group and LPS group,many inflammatory cells were infiltrated. The change of liver in LD group was slight. CONCLUSION:Low dose hydrocortisone may have the protectiive effect on liver in LPS attack rats. High dose and middle dose of hydrocortisone have no effects.     

Effects of cholecystokinin octapeptide on expression of IL-1β, IL-6, IL-4 and IL-10 in lipopolysaccharide-attacked mice

AIM:To observe the effects of cholecystokinin octapeptide (CCK-8) on the expression of proinflammatory cytokines IL-1β, IL-6 and anti-inflammatory cytokines IL-10, IL-4 in LPS- attacked mice. METHODS:Kunming mice were randomly assigned and injected intraperitoneally with LPS alone or/and CCK-8 at different time points. The expression of IL-1β, IL-6, IL-10 and IL-4 in the serum and lung tissues were assayed by ELISA and RT-PCR. RESULTS:The expression of IL-1β, IL-6, IL-10 and IL-4 were upregulated in LPS-attacked mice. Pre-treatment of CCK-8 decreased both IL-1β and IL-6 expression and augmented IL-10 and IL-4 expression in LPS-attacked mice. CONCLUSIONS:CCK-8 exerts an anti-inflammatory effect by inhibiting the expression of IL-1β, IL-6 and increasing the expression of IL-10, IL-4 in LPS-attacked mice, which could alleviate the inflammatory response in lung tissue.     

Inhibitory effect of proanthocyanidins B1 and B2 on inflammation of BV-2 cells induced by lipopolysaccharide

AIM: To investigate the different inhibitory effects of proanthocyanidins B1 and B2, which are isomers, on the inflammatory response of BV-2 cells induced by lipopolysaccharide (LPS). METHODS: MTT assay was used to detect the effects of proanthocyanidins B1 and B2 on the viability of BV-2 cells. LPS (1 mg/L) was used to promote BV-2 cells to secrete inflammatory factors. ELISA, chemotaxis assay and Western blot were used to detect the influence of proanthocyanidins B1 and B2 on the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), cell chemotaxis and phosphorylation of NF-κB. RESULTS: Proanthocyanidins B1 and B2 did not show cytotoxicity effect on BV-2 cells. Proanthocyanidin B1 and B2 inhibited the cell chemotaxis, phosphorylation of NF-κB, and releases of TNF-α and IL-1β. CONCLUSION: Proanthocyanidins B1 and B2 inhibit the inflammatory response of BV-2 cells induced by LPS, and their action intensity didn't show significant difference.     

Effects of Ginsenosides on LPS-induced TF and PAI-1 expression in vascular endothelial cells

AIM: To study the effect of ginsenosides on lipopolysaccharide-induced expression of tissue factor (TF) and plasminogen activator inhibitor type-1 (PAI-1) in vascular endothelial cells (EC), and to investigate the mechanism of ginsenosides in the healthy protection and treatment of cardiovascular diseases. METHODS: Human umbilical vein endothelial cells (HUVEC) were cultured by trypsin digestion method. PAI-1 was measured in the conditioned medium of HUVEC by a specific enzyme-linked immunosorbent assay (ELISA), whereas TF activity was measured in the lysates of these cells by a single step clotting assay. Specific mRNA expressions were determined by Northern blotting. RESULTS: Treatment of HUVEC with LPS resulted in a significant increase in PAI-1 antigen and TF activity. Ginsenosides inhibited this LPS-induced upregulation of PAI-1 protein and TF activity in HUVEC. These effects were also confirmed on the level of specific PAI-1 and TF mRNA expression by Northern blotting. CONCLUSION: Ginsenosides counteract endothelial cell activation by inhibition LPS-induced PAI-1 and TF expression in these cells. This ability of ginsenosides might explain its efficacy in the healthy protection and the treatment of cardiovascular diseases.     

Protective effect of HSF1 on mice with LPS-induced acute lung injury and screening of relevant differentially-expressed genes

AIM: To study the protective effect of heat shock factor1 (HSF1) on the mice with lipopolysaccharide (LPS)-induced acute lung injury (ALI), and to screen the relevant differentially-expressed genes. METHODS: ALI mouse model was established by LPS intracheal instillation. The macroscopic and pathological changes of the lung tissue were observed, and the concentrations of total protein, TNF-α, IL-β, IL-6 and VEGF in the bronchoalveolar lavage fluid (BALF) were analyzed. Differentially-expressed genes in the lung tissues of HSF1^+/+ mice and HSF1^-/- mice with ALI induced by LPS were screened by gene chips. The key gene was verified by real-time qPCR. RESULTS: The macroscopic and pathological changes of the lung injury in HSF1^-/-+LPS mice were more serious than those in HSF1^+/++LPS mice. The concentrations of total protein, VEGF, TNF-α, IL-1β and IL-6 in the BALF of HSF1^-/-+LPS mice were significantly higher than those of HSF1^+/++LPS mice (P<0.05). Compared with the HSF1^+/+ mice, a total of 918 differentially-expressed genes were indentified in the HSF1^-/- mice, among which the expression levels of 65 genes had obvious diffe-rence, with 28 genes up-regulated, including Atg7, ccr1, cxcr2, Tbl1xr1, Mmp9, Pparg, Plcb2, Arrb2, Cntn1, Col4a6, etc, and 37 genes down-regulated, including Fgfr1, Fgfr2, Map4k4, Ddx58, Tfg, Stat3, Smad4, Lamc1, Sdc3, etc. The results of real-time qPCR showed that the mRNA level of CXCR2 in HSF1^-/-+ LPS mice was significantly higher than that in HSF1^+/++ LPS mice, which was consistent with the results of gene chips. CONCLUSION: HSF1 has protective effect on the mice with LPS-induced ALI. CXCR2 may be involved in the protective effect of HSF1 on this process.     

LPS induced B7-H1 expression in pancreatic carcinoma Panc-1 cells

AIM: To explore the mechanism of lipopolysaccharide (LPS)-induced B7-H1 expression in pancreatic carcinoma cell line Panc-1. METHODS: The levels of phosphorylated p38 mitogen-activated protein kinase (p-p38), phosphorylated extracellular signal-regulated kinase (p-ERK) and phosphorylated c-Jun N-terminal kinase (p-JNK) after stimulated with LPS or treated with mitogen-activated protein kinases (MAPKs) inhibitors were detected by Western blotting. The expression of B7-H1 in Panc-1 cells after LPS stimulation or MAPKs inhibitor treatment was measured by real-time PCR and Western blotting. RESULTS: The levels of B7-H1, p-p38, p-ERK and p-JNK were up-regulated with LPS stimulation. The promoted p-p38, p-ERK and p-JNK levels induced by LPS were inhibited by the corresponding MAPKs inhibitors. Furthermore, the inhibitors of p38 and ERK attenuated LPS-induced B7-H1 expression. However, JNK inhibitor had very little effect on LPS-induced B7-H1 expression. CONCLUSION: LPS induces B7-H1 expression in pancreatic carcinoma cell line Panc-1. ERK and p38 are involved in this regulation as the inhibitors of ERK and p38 attenuate LPS-induced B7-H1 expression.     

Protective effect of panaxadiols against brain injury induced by LPS through inhibiting NOS activity and p38 expression

AIM: To explore the protective effect of panaxadiols (PDS) on brain injury induced by endotoxin and its mechanism. METHODS: Rats were divided into control,LPS,LPS+dexamethasone (DEX) and LPS+PDS group, respectively. NOS activity, NO content and phosphorylated p38 expression in brain cortex were assayed 4 h after intravenous injection of LPS. RESULTS: NOS activity, NO content and phosphorylated p38 expression in brain cortex in LPS group were obviously higher than those in LPS group. NOS activity, NO content and phosphorylated p38 expression in brain cortex in LPS+DEX and LPS +PDS groups were obviously lower than those in LPS group. CONCLUSION: The protective effects of PDS against brain injury induced endotoxin may be related to decreasing NOS activity, NO content in the brain tissue, and this process is involved in p38MAPKs signal transduction.     

Protective effect of paeoniflorin on nerve cells in APP/PS1 mice and its mechanism

AIM: To investigate the therapeutic and preventive effects of paeoniflorin (PF) on APP/PS1 mice, and to explore the possible mechanism. METHODS: Fifteen male 5-month-old APP/PS1 non-dominant mice were chosen as normal control group, 15 male 5-month-old APP/PS1 double transgenic mice were used as model group, and 15 male 5-month-old APP/PS1 double transgenic mice treated with 5 mg/kg PF by intraperitoneal injection were allocated in administation group. The learning and memory ability of the mice in each group was detected by Morris water maze. The apoptosis was assessed by TUNEL fluorescence staining. The protein expression of PI3K, Akt, p-PI3K, p-Akt, caspase-3, caspase-9, Bcl-2 and Bax in cerebral cortex and hippocampus was detected by Western Blot. The protein expression levels and distribution of caspase-3 and caspase-9 were detected by immunohistochemistry. RESULTS: (1) Compared with normal control group, the learning and memory ability declined in APP/PS1 model group. Compared with APP/PS1 model group, PF obviously improve the ability of learning and memory in mice. (2) Compared with normal control group, the apoptosis of nerve cells in APP/PS1 model group significantly increased and distributed in wider areas, while that in PF group was reduced (P<0.05). (3) Compared with APP/PS1 model group, PF could significantly lower pro-apoptotic factors, caspase-3, caspase-9 and Bax (P<0.05), and increase the expression of anti-apoptotic factors, p-PI3K, p-Akt and Bcl-2 (P<0.05). CONCLUSION: PF can up-regulate the expression of Bcl-2 and down-regulate the expression levels of caspase-9, caspase-3 and Bax via the activation of PI3K/Akt pathway, thereby inhibiting the nerve cell apoptosis and protecting the nerve cells, so as to treat neurodegenerative diseases.     

Protective effect of Zhenrenyangzang decoction on intestinal mucosal barrier function in ulcerative colitis rats

AIM: To investigate the protective effect of Zhenrenyangzang decoction (ZRYZ) on the intestinal mucosal barrier function and the expression of tight junction proteins, zonula occludens-1 (ZO-1) and occludin, in the colon of rats with trinitrobenzenesulfonic acid (TNBS)-induced ulcerative colitis in order to explore the possible mechanism involved. METHODS: Male Wistar rats were randomly divided into normal group, model group, salazosulfapyridine (SASP) positive control group, high-dose ZRYZ (ZRYZ-H) group and low-dose ZRYZ (ZRYZ-L) group. Except the normal group, the rats in other groups were given the TNBS/50% ethanol mixed solution by enema to make the ulcerative colitis model. The rats in positive control group were given SASP suspension liquid. The rats in ZRYZ-H group and ZRYZ-L group were orally administered with ZRYZ at doses of 30.4 g/kg and 15.2 g/kg, respectively, while the rats in normal group and model group were orally administered with saline. All the drugs were administered to the rats for consecutive 21 d. Disease activity index (DAI) was investigated during the drug treatment, and colon samples were collected after drug administration for evaluating morphological damage score. Intestinal mucosal permeability was measured by detection of lactulose/mannitol (L/M) in urine. Colonic myeloperoxidase (MPO) activity and goblet cell number, serum diamine oxidase (DAO) and D-lactic acid (D-LA) levels, and the colonic expression of ZO-1 and occludin were also measured. RESULTS: Compared with normal group, DAI, morphological damage score, L/M value, colonic MPO activity as well as serum D-LA and DAO levels in model group significantly increased (P<0.05), while goblet cell number as well as the expression levels of ZO-1 and occludin in model group were significantly reduced (P<0.05). Compared with model group, DAI, morphological damage score, L/M value, colonic MPO activity as well as serum DAO and D-LA levels in ZRYZ-H group and ZRYZ-L group were reduced significantly (P<0.05), while goblet cell number as well as the expression of ZO-1 and occludin in ZRYZ-H group and ZRYZ-L group increased significantly (P<0.05). CONCLUSION: ZRYZ protects the intestinal mucosal barrier function in ulcerative colitis rats by reducing intestinal mucosal permeability, and its mechanisms may be related to increasing the expression of ZO-1 and occludin.     

Protective effect of dexmedetomidine-ulinastatin combination on lipopolysaccharide-induced acute lung injury in rats

AIM：To investigate the effects of dexmedetomidine-ulinastatin combination on acute lung injury induced by lipopolysaccharide (LPS) in rats. METHODS：Male Wistar rats were randomly divided into 5 groups: saline control group (NS group) was given saline (5 mL/kg, iv) alone; LPS group (L group) was given LPS (10 mg/kg, over 10 min); dexmedetomidine+LPS group (L+D group) was treated with the additional administration of dexmedetomidine (1 μg·kg -1·h -1) immediately after LPS injection; ulinastatin+LPS group (L+U group) was treated with the addi-tional administration of ulinastatin (50 000 U/kg, ip) immediately after LPS injection; dexmedetomidine+ulinastatin+LPS group (L+D+U group) received dexmedetomidine (1 μg·kg -1·h -1) and ulinastatin (50 000 U/kg) immediately after LPS injection. The animals were sacrificed at 6 h after LPS or NS administration. Partial pressure of arterial oxygen (PaO 2), pH and base excess (BE) were measured, and the lungs were removed for evaluation of histological characteristics and determining the concentrations of TNF-α, IL-1β, macrophage inflammatory protein 2 (MIP-2), malondialdehyde (MDA), nitric oxide (NO), prostaglandin E 2 (PGE 2) and myeloperoxidase (MPO) in lung tissues, lung wet/dry weight ratio (W/D), and albumin in brochoalveolar lavage fluid (BLAF). The pulmonary expression of nuclear factor kappa B (NF-κB) p65 was evaluated by Western blotting. RESULTS：Compared with NS group, PaO 2, pH and BE was lower in L group, which was increased by treatment with dexmedetomidine-ulinastatin combination but not by dexmedetomidine or ulinastatin alone. Compared with NS group, LPS induced marked lung histological injury, which was less pronounced in the animals treated with dexmedetomidine-ulinastatin combination but not dexmedetomidine or ulinastatin alone. The levels of IL-1β, IL-6, MIP-2, MDA, NO and PGE 2 in the lung tissues increased in L group compared with NS group, which were reduced by dexmedetomidine-ulinastatin combination but not by dexmedetomidine or ulinastatin alone. The MPO activity, MDA level and W/D increased in the lung tissues in L group compared with NS group, which was reduced by dexmedetomidine-ulinastatin combination but not by dexmedetomidine or ulinastatin alone. Compared with NS group, the albumin concentration in the BLAF increased, which was reduced by dexmedetomidine-ulinastatin combination but not by dexmedetomidine or ulinastatin alone. Compared with NS group, the expression of NF-κB p65 increased in L group, which was reduced by dexmedetomidine-ulinastatin combination but not by dexmedetomidine or ulinastatin alone.CONCLUSION：Dexmedetomidine-ulinastatin combination has a protective effect on LPS-induced acute lung injury in the rats.     

Lipoxin A4 reduces lipopolysaccharide-induced expression of cyclooxygenase 2 and prostaglandin E2 in human bronchial epithelial cells

AIM: To explore the effects of lipoxin A₄ on the expression of cyclooxygenase 2 (COX-2) in human bronchial epithelial cells (HBECs). METHODS: HBECs were incubated with various concentrations (0.1, 1 and 10 mg/L) of lipopolysaccharide(LPS) for 9 h, or 1 mg/L LPS for different time (3 h, 6 h and 9 h). The levels of COX-2 mRNA in HBECs and prostaglandin E₂ (PGE₂) in the culture supernatant were measured. In addition, the HBECs were exposed to lipoxin A₄ at concentration of 0, 100 and 400 μmol/L after stimulated with LPS at concentration of 1 mg/L for 9 h, and the supernatant of the culture cells was collected for determining the content of PGE₂ by ELISA. The cells were also harvested, and the mRNA and protein levels of COX-2 were analyzed by RT-PCR and Western blotting, respectively. RESULTS: LPS increased the mRNA expression of COX-2 and production of PGE₂ in a dose and time dependent manners in HBECs. Induction of COX-2 mRNA and protein by LPS were inhibited by lipoxin A₄ in a dose-dependent manner. Lipoxin A₄ also significantly decreased LPS-induced production of PGE₂. CONCLUSION: Lipoxin A₄ down-regulates LPS-induced expression of COX-2 and consequently inhibits the production of PGE₂ in HBECs.     

Protective effect of N-acetylcysteine on mice with acute lung injury induced by H9N2 swine influenza virus

AIM: To investigate the effects of N-acetylcysteine (NAC) on acute lung injury induced by H9N2 swine influenza virus (SIV) in mice. METHODS: BALB/c mice were used to establish the animal model of acute lung injury by nasal inoculation of H9N2 SIV. The mice were divided into control group (without SIV infection), H9N2 SIV group (inoculation of H9N2 SIV) and NAC group (inoculation of H9N2 SIV plus pretreatment with NAC). The pulmonary edema was evaluated by determining the lung wet weight/dry weight (W/D) ratio. The pathological changes of the lung tissues were observed. The concontrations of TNF-α, IL-1β and IL-6 in bronchoalveolar lavage fluid (BALF) were measured.The virus titer, T-SOD activity, MPO activity and MDA content in the homogenate of the lung tissues were detected. RESULTS: Treatment with NAC decreased the morality of infected mice, and significantly prolonged the survival time of infected mice. The pathological changes of the lung tissues, the lung W/D ratio and the lung index were relieved when SIV infected the mice treated with NAC. Treatment with NAC significantly decreased the infiltration of inflammatory cells including macrophages, lymphocytes and neutrophils in the BALF. The levels of TNF-α, IL-6, IL-1β and MDA and the activity of MPO were also decreased. Treatment with NAC also significantly increased the T-SOD activity. CONCLUSION: The protective effect of NAC on the acute lung injury mouse model is related to suppression of the oxidative stress and inflammatory responses.     

Protective effect and the possible mechanism of Nano-Se on myocardium of experimental diabetes mice

AIM: To observe the protective effect of Nano-Se on myocardium of experimental diabetes mice. METHODS: Sixty healthy male KM mice were chosen, ten of which were selected randomly as the normal control group. After fasted for 24 h, the rest 50 mice were injected with streptozotocin (STZ, 50 mg/kg) intraperitoneally for 5 d. At 7th d, the blood-sugar was measured from vena caudalis, 40 mice, of which blood-sugar exceeded 16.65mmol/L, were selected and randomized into 4 groups: the positive control group, low dose (25 μg/kg) Nano-Se group, mid dose (50 μg/kg) Nano-Se group, high dose (50 μg/kg) Nano-Se group. All mice were given intragastric administration of 0.2 mL normal saline and corresponding dose of Nano-Se. The body weights were measured every week, and the dose of which was adjusted according to the change of the body weights. 8 weeks later, the mice were killed and cardiac muscle of the left ventricle was taken. The myocardium was prepared to 10% homogenate for measuring SOD, GSH-Px activity and MDA content. The myocardial cell apoptosis was measured by TUNEL. The expressions of Bc1-2 and Bax proteins were determined by immunohistochemistry. RESULTS: Compared to normal group, the SOD and GSH-Px activities in positive control group decreased, MDA level increased, the rate of myocardial cell apoptosis increased significantly, Bc1-2 protein expression deceased and Bax protein expression increased. Compared to positive control group, the SOD and GSH-Px activities in low and mid dose Nano-Se groups expression increased, MDA level decreased, myocardial cell apoptosis rate decreased, Bc1-2 protein expression increased and Bax protein expression decreased. Moreover, the SOD and GSH-Px activities in high dose Nano-Se group decreased obviously compared to those in mid dose Nano-Se group. MDA level and myocardial cell apoptosis rate increased, Bc1-2 protein expression decreased and Bax protein expression increased, no significant difference in SOD, GSH- Px activity, MDA level and myocardial cell apoptosis rate was observed compared with positive control group. CONCLUSION: The damage of cardiac muscle is alleviated when a certain dose of Nano-Se is supplied to diabetes mice. The protective mechanism may be related to antioxidation, blood-sugar adjustment and the increase of Bc1-2 expressing.     

Adipophilin induces expression of inflammatory factors through ERK1/2-AP-1 signaling pathway

AIM: To observe the effects of adipose differentiation-related protein (adipophilin) on the expression of inflammatory factors in RAW264.7 macrophage and to clarify the related mechanism. METHODS: The cell models with high expression and low expression of adipophilin were constructed by transfecting PA317 packaging cells with stable high or low expression adipophilin retroviral vectors into the RAW264.7 cells. The concentrations of IL-6, MCP-1 and TNF-α in the cell culture medium were detected by ELISA. The protein levels of AP-1, p-AP-1, ERK1/2 and p-ERK1/2 were measured by Western blot. The protein levels of adipophilin, p-ERK1/2 and p-AP-1 and the releases of the inflammatory factors in the RAW264.7 cells treated with or without ERK1/2 inhibitor PD98059 or AP-1 inhibitor curcumin were determined. RESULTS: The RAW264.7 cells with high expression of adipophilin had higher levels of IL-6, MCP-1 and TNF-α, and higher protein levels of p-AP-1 and p-ERK1/2 than those in the cells with low expression of adipophilin. ERK1/2 inhibitor had no significant effect on the expression of adipophilin, but the protein expression of ERK1/2 and AP-1 was significantly inhibited (P<0.05). The administration of AP-1 inhibitor curcumin had no significant effect on the protein expression of adipophilin and ERK1/2, but the protein expression of AP-1 was significantly inhibited (P<0.05). At the same time, the releases of inflammatory factors IL-6, MCP-1 and TNF-α were significantly decreased. CONCLUSION: Adipophilin may regulate the expression of inflammatory factors through ERK1/2-AP-1 pathway in RAW264.7 macrophages.