Expression And Clinical Significance Of BNDF In Hippocampi Tissues Resected From Children With Temporal Lobe Epilepsy

ObjectivesEpilepsy is a common kind of chronic disease of the nervous system among children.Even with standard drug treatment,20to30%of the cases become intractable epilepsy,34%of which is temporal lobe epilepsy(TLE). Operation is satisfactory for60%-70%ofthe children with intractable epilepsy. The histopathology of the hippocampi tissuesindicates the pullulation of mossy fibre and the remodeling of the synapses whichrecombinate the neural networks. Recombination of the neural networks is one of theimportant pathogenesis of intractable epilepsy in children. Recent researches find out thatthe over expression of brain derived neurotrophic factor(BDNF) may be the importantmolecular pathogenesis of the recombination of the neural networks. The study will try tofind out the importance of the over expression of BDNF in the pathogenesis of TLE bystudying the difference of the expression of BDNF between trial groups (TLE cases) andcontrol groups(chlidren without epilepsy) and by studying the relationship between theexpression of BDNF and the clinical feature of children with TLE and the satisfactorydegree of operation.Materials and MethodsThe trial group is hippocampi tissues of16children with temporal lobe epilepsy fromthe department of neurosurgery of Fuzou general hospital of Nanjing military region datedfrom March2012to March2013. And the control group is the tissues form8childrenwithout epilepsy from the same department dated from September2011to March2013.Immunohistochemistry were used to test the expression of BDNF in the hippocampi tissues,and the results are observed under the micorscope and analysised with the Ridit test. Bothgroups are followed up from half to one year after operation and the relationship betweenthe expression of BDNF and the clinical feature and the satisfactory degree of operation are recorded and analysised.Results1.Trial group:16cases of TLE, gender:8boys (50%),8girls (50%). Age:7～17（13.3±4.2）Years old. Course:2～14（5.5±2.0）years. The expression of BDNF in thehippocampi tissues: weakly positive1case, positive2cases, strongly positive13cases.Control group:8cases of non-epilepsy, gender:5boys (62.5%),3girls (37.5%). Age:5～18（12.5±5.3）Year-old. The expression of BDNF in the hippocampi tissues: weaklypositive7cases, positive1case. The result of Ridit test analysis indicates there isstatistical significance (Hc=9.2472，P=0.0024). so the Expression of BDNF protein weresignificantly inscresed in the hippocampi tissues resected from trial group compared withthat of control group.2.The relationship between the clinical feature of trial group and the expression ofBDNF: strike type: generalized epilepsy:12cases(the expression of BNDF stronglypositive:12cases), complex partial epilepsy:1case strongly positive of the expression ofBNDF1case), absence epilepsy2cases(weakly positive1case, positive1case)automatism1case(positive1case). Frequecy of strike＞10times/month:13cases (theexpression of BNDF weakly positive1case, positive2cases, strongly positive10cases);＜10times/month3cases (positive3cases). Probable cause: craniocerebral trauma7cases(positive1case, strongly positive6cases) febrile convulsion2cases(strongly positive2cases) intracranial infection3cases(weakly positive1case, strongly positive2cases),idiopathic4cases(positive1case, strongly positive3cases).3.The relationship between the expression of the BDNF and the satisfactory degreeof operation in trial group: the16cases of the trial group were followed up after operationfor half to one year. Grade I (according to Engel classification)3cases (the expression ofthe BDNF strongly positive3cases), Grade II7cases (the expression of the BDNFstrongly positive7cases) Grade III5cases(the expression of the BDNF strongly positive2cases, positive2cases, weakly positive1case), Grade IV1case (the expression of theBDNF strongly positive1case). Satisfaction evaluation of the operation: satisfactory10cases(the expression of the BDNF strongly positive10cases), unsatisfactory6cases (theexpression of the BDNF strongly positive3cases, positive2cases, weakly positive1case).The satisfactory degree of operation is positive correlated with the degree of expression ofthe BDNF according to the result of Spearman rank correlation analysis（r=0.6172， P=0.0109）. It is thought that with the increase of the expression of the BNDF, thesatisfactory degree of operation increas.Conclusions1.The result indicate the increase of the expression of BDNF protein in hippocampustissue may play an inportant role in the development of temporal lobe epilepsy forchildren.2.The relationship between the expression level of BDNF with the clinicalcharacteristics relate to many factors.3.The remove of the tissues with high expression of BDNF is the theoretical basis ofthe effectiveness of operation in the therapy of epilepsy for children.