α2δ1-NMDA Receptor Complex And PINK1 Regulate The Mechanism Of Brain Injury After Intracerebral Hemorrhage In Mice And The Interventional Effect Of Pregabalin

Objective: Intracerebral hemorrhage(ICH)is a serious cerebrovascular disease that accounts for about 10-15% of all strokes,has a high mortality rate,is prone to serious secondary injuries and has a significant impact on human public health.The main pathological factors in cerebral haemorrhage are chronically high systolic blood pressure leading to hypertension and cerebral amyloid angiopathy.Cerebral haemorrhage can lead to abnormal release of neurotransmitters,cerebral ischaemia,cell membrane depolarisation,mitochondrial dysfunction and predispose to neurological dysfunction.It has been reported that there are still limitations in the treatment of cerebral haemorrhage.α2δ-1 is a subunit of voltage-gated Ca2+ channels(VGCCs)that acts on glutamate receptors(N-methyl-D-aspartate receptors(NMDARs))and provides relief from neuropathic pain.PTEN-induced kinase 1(PINK1)is protective against mitochondrial apoptosis and dysregulated mitochondrial quality control by activating the mitochondrial damage response pathway.The relationship between the α2δ-1-NMDA receptor complex and PINK1 and the mechanisms of brain loss after cerebral haemorrhage is not yet fully understood.The site of action of widely used clinical analgesics,such as gabapentin and pregabalin,targets α2δ1.By inhibiting the activity of α2δ1,a significant reduction in NMDA receptor activity is achieved and brain damage after cerebral haemorrhage is reduced.The effectiveness of pregabalin analogues in the treatment of post-cerebral haemorrhage is also unclear at present.Methods:1.Firstly,WT mice and α2δ-1 knockout mice were established for ICH model.The expression levels of Glu N1 and α2δ-1 were measured by Western blot and RT-PCR,and the interaction between them was detected by immunoprecipitation.neuronal apoptosis was detected by TUNEL,and the expression of inflammatory factors was detected by ELISA.The forelimbs were selected to detect neurological deficits in mice using two neurofunctional behavioural assays: the asymmetry and the corner test.Cerebral haematomas were detected using the brain water content and lesion volume assay.2.PINK1 mRNA was upregulated but its protein was downregulated in patients with ICH;PINK1 reduction occurred mainly in microglia in a mouse ICH model;PINK1 overexpression attenuated ICH-induced neurobehavioral deficits;PINK1 attenuated ICH-induced brain damage by promoting mitochondrial autophagy in microglia.3.The National Institutes of Health Stroke Scale(NIHSS)was applied to assess the neurological function of the patients.Patients’ quality of life was assessed by the Activities of Daily Living Scale(ADL).Clinical outcomes were analysed using the Glasgow Outcome Scale(GOS).Matrix metalloproteinase 2(MMP2)and matrix metalloproteinase 9(MMP9)levels were assessed by ELISA.Results:1.ICH upregulates the expression levels of α2δ-1 and Glu N1.Knockdown of the α2δ1 gene significantly reduced apoptosis caused by loss of cerebral haemorrhage,and gabapentin treatment acting on the α2δ-1 gene also significantly reduced the occurrence of apoptosis.Knockdown of theα2δ-1 gene also reduced the expression levels of inflammatory factors caused by cerebral haemorrhage,resulting in improved behaviour of neurological function as well.2.PINK1 mRNA is upregulated but its protein is downregulated in patients with ICH.reduction of PINK1 occurs mainly in microglia in the ICH model.overexpression of PINK1 rescues ICH-induced behavioural deficits.PINK1 protects against ICH-induced brain damage by promoting mitochondrial autophagy in microglia.After 2 weeks of treatment,the haematoma volume and the levels of MMP2 and MMP9 were significantly smaller in the observation group than in the control group.After 12 weeks of follow-up,the observation group had a better prognosis.After 2 weeks of treatment,the NIHSS score in the observation group was significantly lower than that in the control group and the AD L score was significantly higher than that in the control group.Conclusion:1.Knockdown of α2δ-1 gene reduced the expression of inflammatory factors induced by cerebral haemorrhage and improved neurofunctional behaviour in mice.α2δ-1 knockdown alleviated cerebral haematoma in mice with cerebral haemorrhage,had significant modulatory effects on secondary damage including neuronal apoptosis and inflammation,and significantly improved neurological function in mice with cerebral haemorrhage.It indicates that the deletion of α2δ-1 gene could provide useful therapeutic clues for the treatment of cerebral haemorrhage.2.PINK1 is neuroprotective and may reduce the harmful effects of brain injury after ICH by promoting mitochondrial autophagy,which may provide an effective approach for ICH treatment.3.In the treatment of acute cerebral haemorrhage,Prevacid reduces brain damage in patients with cerebral haemorrhage and has a prognostic boost for patients.