ABSTRACT
Objective To study the effect of the promoter methylation of coagulation factor Ⅶ (FⅦ) on the coagulation factor Ⅶ activity (FⅦa) in traumatic brain injury (TBI) patients,and the correlation between the promoter methylation in FⅦ and intracranial progressive hemorrhagic injury (PHI).Methods A prospective analysis was conducted on 79 patients with moderate-severe TBI admitted to emergency department from August 2010 to August 2014.The peripheral venous blood samples were collected at admission and then were delivered for measurement of FⅦa.Genomic DNA was isolated from patient blood,and the promoter methylation in FⅦ (CpG2,CpG3,CpG4,CpG5,and CpG6) were analyzed.According to the level of plasma FⅦa,the patients were divided into FⅦa ≥90％ group and FⅦa ＜ 90％ group.Based on the presence of PHI,the patients were divided into PHI group and non-PHI group.The FⅦ promoter methylation,age,gender,systolic blood pressure,Glasgow Coma Scale (GCS),length of stay and mortality between FⅦa≥90％ group and FⅦa ＜ 90％ group,PHI group and non-PHI group were compared.Results There were no significant differences in age,gender,systolic blood pressure,GCS,LOS,and mortality between FⅦa ≥90％ group and FⅦa ＜90％,PHI group and non-PHI group (P ＞ 0.05).The methylation of CpG3 in FⅦa ≥90％ group was less than that in FⅦa ＜90％ group (0.83 ±0.05 vs.0.85 ±0.03) (P＜0.05),while there were no significant differences in other CpG sites between these two groups (P ＞ 0.05).No significant differences in all of methylation levels of the CpG sites between PHI group and non-PHI group were found (P ＞0.05).Conclusions The promoter methylation of FⅦ affects plasma FⅦa concentrations,and higher methylation results in lower FⅦa.The promoter methylation of FⅦ is not associated with PHI in TBI patients.
ABSTRACT
Objective To study the correlation between the coagulation factor Ⅶ (F Ⅶ) and progressive hemorrhage after brain contusion in mice and provide the experimental evidence for the clinical application of recombinant human FⅦa.Methods Twelve male BALB/c mice were given liposomeencapsulated FⅦsiRNA via tail vein at doses of 1,3,5 and 10 mg/kg with 3 mice per dosage.The other 3 mice received equivalent volume of normal saline as controls.Two days after the injection,mice blood sampling was used to detect FⅦ mRNA expression in liver using real-time PCR,level of plasma FⅦ using ELISA method,and activity of plasma FⅦ using chromogenic substrate assay.The optimal dose at which F Ⅶ expression was inhibited was determined.Thirty BALB/c male mice were assigned to two groups (n =15 per group) according to the random number table:FⅦ-suppressing group,mice were injected with FⅦsiRNA at the optimal dose and control group,mice were injected with same volume of negative control vector.The model of brain contusion was established in both groups.Volume of hemorrhage following brain contusion was measured at 3,24 and 72 h postinjury,and hematoma volume at 24 and 48 h postinjury.Results Liposome-encapsulated siRNA delivery down-regulated FⅦ expression in the mouse liver.Level and activity of plasma FⅦ were also reduced significantly.The optimal siRNA dose was 3 mg/kg.At 3,24 and 72 h postinjury,relative volume of brain hemorrhage in FⅦ-suppressing group was 1.46 ± 0.10,1.82 ± 0.23 and 2.28 ± 0.15 respectively,significantly higher than that in control group (1.00 ± 0.25,1.20 ± 0.31 and 1.20 ± 0.22 respectively) (P ＜ 0.05).At 24 and 48 h postinju-ry,volume of hematoma in FⅦ-suppressing group was (6.7 ± 1.5)mm3 and (9.8 ± 1.0) mm3,significantly higher than that in control group [(5.2 ± 1.2) mm3 and (5.5 ± 1.5) mm3] (P ＜0.01).Conclusions Level of FⅦ in vivo relates closely to the progressive hemorrhage of brain contusion in mice.Administration of FⅦ is effective to reduce the incidence of progressive hemorrhage.