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Objective To investigate the expression of the hypoxia-inducible factor (HIF)-1α in rat brain neurons and the intervention of β-sodium aescinate after restoration of spontaneous circulation (ROSC).Methods Sixty SD adult rats were randomly (random number) divided into 3 groups (n =20),namely experiment group,control group and sham operation group.(1) The rats of experiment group were injected intraperitoneally with β-sodium aescinate (5 mg/kg) immediately after ROSC.(2) The rats of control group received normal saline injected intraperitoneally instead of β-sodium aescinate solution.(3)The rats of sham operation group did not have cardiac arrest and β-sodium aescinate intervention.Cardiac arrest rat model was established by using asphyxiation and intra-venous potassium chloride solution.Blood samples were taken 1 h,6 h,12 h and 24 h after ROSC,and subsequently rats were sacrificed and their brain tissues were harvested.The expressions of HIF-1 α mRNA,vascular endothelial growth factor (VEGF)mRNA and erythropoitin (EPO) mRNA and their protein levels in rat brain neurons were detected by using RT-PCR and immunohistochemistry,and the levels of serum neuron-specific enolase (NSE) and S100β proteins were determined by using enzyme-linked immunosorbent assay.The t test or one-way ANOVA was used to assess overall differences among groups for each of the variables,followed by Bonferroni test for multiple comparisons.Pearson method was used for correlation analysis.Results Compared with the sham operation group at intervals of 1 h,6 h,12 h and 24 h after ROSC,levels of serum S100β and NSE proteins were significantly increased in rats of the control group (P ＜ 0.05).Meanwhile,the expressions of HIF-1 α mRNA,VEGF mRNA and EPO mRNA and their protein levels in rat brain neurons were significantly increased in the control rats (P ＜0.05).Compared with the control group at intervals of 1 h,6 h,12 h and 24 h after ROSC,levels of serum NSE and S100β proteins were significantly decreased in rats of the experiment group (P ＜ 0.05).Whereas,the expressions of HIF-1 α mRNA,VEGF mRNA and EPO mRNA and their protein levels in rat brain neurons were significantly increased in rats of the experiment group (P ＜0.05).HIF-1 α mRNA was positively correlated with EPO mRNA and VEGF mRNAs (r =O.866,P ＜0.05 ; r =0.952,P ＜ O.01).Conclusions The expression of hypoxia-inducible factor-1 α is increased in rat brain cells after ROSC,and β-sodium aescinate up-regulates the expression of hypoxia-inducible factor1 α mRNA and protein levels.The up-regulated expression of hypoxia-inducible factor-1α improves the resistance of brain cells to ischemia and hypoxia contributing neuronal protection,which might be due to upregulated EPO and VEGF expressions induced by hypoxia-inducible factor-1α.
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Objective To investigate the neutrophil elastase (NE) in patients with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS).Methods Thirty-six patients of ALI/ARDS and 16 healthy volunteers(control group)were involved in the study.The patients of ALI/ARDS were divided into three groups:group A (the oxygenation index was 201-300 mm Hg,1 mm Hg=0.133 kPa),group B (150-200 mm Hg),and group C (<150 mm Hg).The NE in serum and bronchoalveolar Lavage fluid (BALF) were measured.Results The NE in the serum and BALF in group A [(1.76±0.63)nmol/L and (1.67±0.59)nmol/L],group B [(3.26±0.51)nmol/L and (3.64±0.56)nmol/L] and group C [(4.56 ±0.68)nmol/L and (4.62±0.39)nmol/L] were much higher than that in control group [(0.67±0.54)nmol/L and (0.62±0.48)nmol/L].The NE in the serum and BALF of dead patients were higher than that in patients who were alive.Moreover,the NE in the patients of ALI/ARDS was inversely related to the oxygenation index (r=-0.901,P＜0.01). Conclusion The NE in patients of ALI/ARDS is higher than that in healthy people,and it is significantly related to the severity and the prognosis of ALI/ARDS.