ABSTRACT
In order to study the distribution of virulence genes of Listeria monocytogenes (Lm) in Hebei Province,29 virulence genes of Lm,including Listeria monocytogenes pathogenicity islands Ⅰ (LIPI-Ⅰ:prfA,plcA,plcB,hlyA,mpl and actA),10 internalins genes (inlA,inlB,inlC,inlD,inlE,inlF,inlG,inlH /C2,inlI and inlJ) and the other 13 virulence-associated genes (bsh,srtA,iap,sigB,virR,mprF,dltA,dltB,dltC,dltD,srtB,fbpA and hpt) were detected by PCR.Results showed that in the 91 Lm strains,the detection rate of 23 virulence genes were 100％.The 29 virulence genes of 26 Lm strains were all detected,and 65 Lm strains had different deletion of 6 virulence genes inlD,inlF,inlG,inlH /C2,inlJ and mpl.The deletion rate of inlG and inlF were 60.44％ and 54.95％,respectively,following by mpl gene,with a deletion rate of 19.78％.According to the absence of virulence genes,91 strains could be divided into 10 subtypes,and the dominant virulence subtypes was type Ⅰ with all 23 virulence genes.The deletion rate of virulent genes in Shijiazhuang was higher than that in northern Hebei.It is suggested that the rate of virulence gene of food-borne Lm in Hebei Province is high,and the virulence gene deletion patterns has diversity and regional differences.
ABSTRACT
AIM:To investigate the neuroprotective effect of progesterone against adenosine triphosphate (ATP)-injured human neuroblastoma SH-SY5Y cells.METHODS:The SH-SY5Y cells in the logarithmic phase were divided into different groups according to the progesterone and ATP concentrations.The cell viability was measured by CCK-8 assay.The membrane permeability was detected using fluorescent dye YO-PRO-1.Cytosolic Ca2+ concentration was measured with fluorescent dye Fluo-3/AM.The expression of purinergic P2X7 receptor was assessed by Western blot.RESULTS:The viability of the SH-SY5Y cells was significantly decreased (P ＜ 0.05) and YO-PRO-1 uptake was obviously increased (P ＜ 0.05) in a concentration-dependent manner compared with control group when SH-SY5Y cells were treated with ATP at 1,3,5 and 7 mmol/L for 2 h.The viability reduction of the SH-SY5Y cells induced by ATP was obviously counteracted by treatment with progesterone at 3,10 and 30 nmol/L for 30 min (P ＜ 0.05) as compared with ATP group.YO-PRO-1 fluorescence enhancement induced by ATP in SH-SY5Y cells was significantly reduced (P ＜ 0.05) by progesterone (30 nmol/L) or P2X7 receptor antagonist KN-62 (500 nmol/L) pretreatment for 30 min,and no obvious difference between treatments with progesterone and KN-62 was observed.Cytosolic Ca2+ fluorescence intensity in normal group was a little,but that in ATP group was increased (P ＜ 0.05).Progesterone or KN-62 pretreatment significantly decreased the cytosolic fluorescence intensity of Ca2+ induced by ATP (P ＜ 0.05).However,no obvious difference between treatments with progesterone and KN-62 was found.The expression of P2X7 receptor in ATP group was significantly higher than that in control group (P ＜ 0.05),and progesterone inhibited ATP-induced P2X7 receptor expression (P ＜ 0.05).CONCLUSION:Progesterone inhibits P2X7 receptor expression,membrane pore formation,intracellular Ca2+ increase and cell death induced by ATP,so progesterone may protect SH-SY5Y cells against ATP-induced injuries.
ABSTRACT
AIM:To investigate the neuroprotective effect of progesterone against adenosine triphosphate (ATP)-injured human neuroblastoma SH-SY5Y cells.METHODS:The SH-SY5Y cells in the logarithmic phase were divided into different groups according to the progesterone and ATP concentrations.The cell viability was measured by CCK-8 assay.The membrane permeability was detected using fluorescent dye YO-PRO-1.Cytosolic Ca2+ concentration was measured with fluorescent dye Fluo-3/AM.The expression of purinergic P2X7 receptor was assessed by Western blot.RESULTS:The viability of the SH-SY5Y cells was significantly decreased (P ＜ 0.05) and YO-PRO-1 uptake was obviously increased (P ＜ 0.05) in a concentration-dependent manner compared with control group when SH-SY5Y cells were treated with ATP at 1,3,5 and 7 mmol/L for 2 h.The viability reduction of the SH-SY5Y cells induced by ATP was obviously counteracted by treatment with progesterone at 3,10 and 30 nmol/L for 30 min (P ＜ 0.05) as compared with ATP group.YO-PRO-1 fluorescence enhancement induced by ATP in SH-SY5Y cells was significantly reduced (P ＜ 0.05) by progesterone (30 nmol/L) or P2X7 receptor antagonist KN-62 (500 nmol/L) pretreatment for 30 min,and no obvious difference between treatments with progesterone and KN-62 was observed.Cytosolic Ca2+ fluorescence intensity in normal group was a little,but that in ATP group was increased (P ＜ 0.05).Progesterone or KN-62 pretreatment significantly decreased the cytosolic fluorescence intensity of Ca2+ induced by ATP (P ＜ 0.05).However,no obvious difference between treatments with progesterone and KN-62 was found.The expression of P2X7 receptor in ATP group was significantly higher than that in control group (P ＜ 0.05),and progesterone inhibited ATP-induced P2X7 receptor expression (P ＜ 0.05).CONCLUSION:Progesterone inhibits P2X7 receptor expression,membrane pore formation,intracellular Ca2+ increase and cell death induced by ATP,so progesterone may protect SH-SY5Y cells against ATP-induced injuries.