ABSTRACT
Proline-rich transmembrane protein 2 (PRRT2) is the leading cause of paroxysmal kinesigenic dyskinesia (PKD), benign familial infantile epilepsy (BFIE), and infantile convulsions with choreoathetosis (ICCA). Reduced penetrance of PRRT2 has been observed in previous studies, whereas the exact penetrance has not been evaluated well. The objective of this study was to estimate the penetrance of PRRT2 and determine its influencing factors. We screened 222 PKD index patients and their available relatives, identified 39 families with pathogenic or likely pathogenic (P/LP) PRRT2 variants via Sanger sequencing, and obtained 184 PKD/BFIE/ICCA families with P/LP PRRT2 variants from the literature. Penetrance was estimated as the proportion of affected variant carriers. PRRT2 penetrance estimate was 77.6% (95% confidence interval (CI) 74.5%-80.7%) in relatives and 74.5% (95% CI 70.2%-78.8%) in obligate carriers. In addition, we first observed that penetrance was higher in truncated than in non-truncated variants (75.8% versus 50.0%, P = 0.01), higher in Asian than in Caucasian carriers (81.5% versus 68.5%, P = 0.004), and exhibited no difference in gender or parental transmission. Our results are meaningful for genetic counseling, implying that approximately three-quarters of PRRT2 variant carriers will develop PRRT2-related disorders, with patients from Asia or carrying truncated variants at a higher risk.
Subject(s)
Humans , Dystonia , Epilepsy, Benign Neonatal/genetics , Membrane Proteins/genetics , Mutation , Nerve Tissue Proteins/genetics , Pedigree , Penetrance , Seizures/geneticsABSTRACT
Objective: To investigate the electroencephalogram (EEG) characteristics, cerebral blood fl ow, glucose metabolism, and pathological characteristics in cats kindled by pentylenetetrazol (PTZ). Methods: Ten adult male cats received intramuscular injections of PTZ at a sub-convulsive dose of 25 mg/kg once daily. Cats were considered to be kindled when a class V or above seizure was observed. Subsequently, scalp EEG, 99mTc-ECD-single-photon emission computed tomography (SPECT), 18FDG-positron emission tomography (PET), and Cresyl violet staining were employed to evaluate brain activity, cerebral blood fl ow, glucose metabolism, and pathological characteristics representing epileptic foci during interictal stages. Results: The EEG data revealed bilateral dissymmetry paroxysmal activity in the form of δ and θ waves, as well as paroxysmal spikes and sharp waves instead of symmetric highamplitude rhythm of 8-12 Hz in cats kindled by PTZ compared to controls. In addition, low blood perfusion and low glucose metabolism unilaterally in the temporal lobe were observed in PTZ-kindled cats, in contrast to the bilateral symmetrical blood perfusion and high glucose metabolism observed in control cats. Pathological examinations showed a thickening of white matter in the ipsilateral temporal region and a thinning of gray matter in PTZ-kindled cats. Microscopically, we observed a structure disturbance of hippocampal CA3 area in PTZ-kindled cats. Conclusion: Epileptic foci of PTZ-kindled cats were localized to the unilateral temporal lobe, in a manner highly similar to the pathophysiology of human temporal lobe epilepsy.
ABSTRACT
Objective To explore the role of inositol requiring enzyme 1 α (IRE1α) mediated endoplasmic reticulum stress associated apoptotic molecules in hippocampal neuronal injury in rats with status epilepsy following lithium-pilocarpine.Methods All 96 Wistar rats were randomly divided into control group and status epilepsy (SE) group.The SE group was further divided into 5 subgroups (3,6,12,24,48 h) according to different time points.pmmunofluorescence was used to observe the expressions of endoplasmic reticulum stress (ERS) markers glucose-regulating protein 78 kd (GRP78) and phosphoIRE1α (active form of endoplasmic reticulum resident protein IRE1α) at the CA3 area of rats in each group.Then,the expressions of IRElα mediated downstream apoptotie markers phospho-c-JunN-terminalkinase (JNK) and caspase12 were detected.Finally,TUNEL assay was used to observe neuronal apoptosis of hippocampal CA3 area at different time points after SE in rats.Results Immunofluorescence showed that GRP78 and phospho-IRE1α positive neurons were significantly increased in the SE subgroups compared with control group (6.90％ ± 0.96％,4.60％ ± 1.12％,respectively) and 12 h subgroup reached the peak (GRP78:87.45％ ±3.63％,F =356.82,P ＜0.05; phospho-IRE1α:86.90％ ±3.82％,F =300.80,P ＜ 0.05).Immunohistochemistry and Western blot demonstrated that the levels of phospho-JNK and caspase12 in the SE subgroups were significantly higher than that in the control group which reached the peak at 12 h after SE.The changes were in accord with phospho-IRE1α.Simultaneously,hippocampal neuronal apoptosis was detected in each SE subgroup and was most severe at 12 h after SE,which showed similar changes to the expressions of phospho-IRE1α,phospho-JNK and caspase12.Conclusions ERS was induced in rats following SE evidenced by increasing the expression of GRP78.IRE1α may promote hippocampal neuron apoptosis in rats following SE through activating JNK and caspase12.
ABSTRACT
ObjectiveConstruction and identification of wild-type and mutant human o-synuclein (SNCA) gene lentiviral expression vector, and its stable transfection into the rat pheochromocytoma cells.MethodsThe genes were synthesized with particular primer, amplified by PCR and cloned into the lentiviral vector expression plasmid pGC-FU ( with green fluorescent protein (GFP) gene) to construct a lentiviral vector expression plasmid pGC-FU-SNCA-GFP and pGC-FU-SNCA-GFP.After digestion and sequencing,pGC-FU-SNCA-GFP,pGC-FU-SNCA-GFP plasmidandpackaging plasmidpHelper1. 0,pHelper2. 0 were co-transfected into rat pheochromocytoma cells (PC12 cells).A stable transfection was established in the PC12 cells. Results By detecting the level of tagged protein of GFP and the target protein, the pGC-FU-SNCA-GFP and pGC-FU-SNCA-GFP expression in target cells was verified. MTT assay was employed to detect cell apoptosis in lentiviral pGC-FU-SNCA-GFP transfected group, lentiviral pGC-FU-SNCAmu-GFP transfected group ( experimental groups), without virus group ( control group) and empty vector group( total four groups cells). After transfection, at different timepoints ( 1, 2, 3, 4 and 5 d) the proliferation of cells was slowed ( the F value was 4. 534, 196. 285, 411. 829, 1282. 049, 3135. 559, all P ＜0.05). PI single staining was used to examine the cell cycle. The percentages of G1 phase, G2 phase,M phase cells were all statistically significant ( the F value was 885.79, 45.03,207.11 ,all P ＜0. 05). The percentage of G1 phase cells in the four groups cells increased significantly (CON group:59. 10 ±0. 35, NC group:68.24 ±0.60, OE group:71.73 ±0. 11, OE group:74.66 ±0.35). Conclusion This study constructs a foundation for further investigation on the basic function of SNCA and apoptosis related diseases.