The Expression Of TRPC3and TRPC6in The Epileptic Cortex In Patients With Tuberous Sclerosis Complex

BackgroundThe tuberous sclerosis complex (TSC) is autosomal dominant inherited disease.Themain clinical manifestations are epilepsy, mental retardation and sebaceous adenoma (Vogttriad).And more than a third of the patients suffer from medically intractable epilepsygradually.TSC epilepsy patients with cortical dysplasia lesions and cortical nodules districtappears characteristic of Malformed neuron（sMNs）,such as dysmorphic neurons (DNs) andgiant cell (Giant cells, GCs), which is the most typical pathological signs for braindamage.Clinical electrophysiology study found that these two cell types might attack as theTSC lesions epilepsy pacemaker in the past.However the main mechanism involved in theseizures has not been elucidated.TRPC（Canonical TRP） as a class of non-selective cationchannels of intracellular calcium concentration which can be adjusted is much moreconcern about the function study. The TRPC has high expression in the mammalian centralnervous system involved in the cell membrane receptor to activate phospholipaseC-mediated calcium influx, and studies have found that cells of epileptogenic lesions inTSC existence of the calcium influx caused by abnormal electrical activity of neurons.Preliminary studies have found that part of the subtypes of TRPC（TRPC3、TRPC6）expression in FCD（Focal cortical dysplasia）the epileptogenic lesion was significantlyupregulated,and mainly distributed in FCD epilepsy seizures characteristic of neurons–“Malformed neurons”. TCS and FCD have similar histopathological features, namelyMalformed neurons (MNs), including dysmorphic neurons (DNs) and giant-cells (GCs).SoTRPC3and TRPC6may be the abnormal expression of TSC epileptogenic lesions,and maybe due to seizures and TSC which is closely related to, but little research has been rarelyreported. In the present study, we use Western blot, immunohistochemistry andimmunofluorescence double-labeled detection TRPC3and TRPC6expression in the braintissue of patients with tuberous sclerosis epilepsy lesions skin, and explore the possible role of TRPC channels in seizures, to reveal the relationship between TRPC channels and TSCepileptogenic and provide important theoretical basis.ObjectiveTo detect the expression and disposition of TRPC3and TRPC6in the cortical lesions ofpatients with epilepsy from tuberous sclerosis complex,and explore the TRPC3and TPC6which are involved in the possible mechanisms of seizures resulted from tuberoussclerosis complex.Methods26clinical cases of TSC and10cases of non-epileptic brain tissues were enrolled instudy, and the expression pattern of TRPC3and TRPC6were observed by western blotanalysis and immunohistochemistry.Results1. Western-blot analysis showed that TRPC3and TRPC6expression issignificantly higher in TSC group compared with control group (P <0.05）;2. Immunohistochemistry analysis showed that the expression of TRPC3andTRPC6is significantly higher in TSC group compared with that of controlgroup (P <0.05）.The expression of TRPC3and TRPC6were stronger inmisshapen cells, including dysmorphic neurons （DNs） and giant cells （GCs）than in other cell;3. Double labeling experiments indicated that TRPC3+and TRPC6+MNs wereco-localized with the IR of the neuronal markers NeuN and NF-200. However,we observed no TRPC3+and TRPC6+MNs that expressed GFAP and Vimentin,Vimentin+astrocytes were co-localized with TRPC3+and TRPC6+.ConclusionThe increased expression of TRPC3and TRPC6in epileptic cortex of patientswith TSC, as well as the specific cellular distribution pattern, suggesting that TRPC3and TRPC6may be closely involved in the pathogenesis of epilepsy in patient withTSC.