Molecular Mechanism Of KLKB1 Alleviates Vascular Dementia Via Inhibiting Ferroptosis

Objective: Many studies have demonstrated that ferroptosis is involved in the pathogenesis of vascular dementia(VaD),but the specific mechanism of action is unclear.This study aims to explore the specific mechanism of action between ferroptosis and vascular dementia(VaD),in order to find effective therapeutic targets for treating VaD.Methods: 1.Ligation of bilateral common carotid artery stenosis(BCAS)in rats to induce chronic cerebral hypoperfusion to establish a VaD animal model.After 2 months of ligation,foot dysfunction test and Morris water maze were used to assess the behavioral and cognitive abilities of the rats,TTC staining was used to assess the infarct volume of the rat brain tissue,HE staining was used to observe the pathological changes in the rat hippocampus,and the levels of ferroptosis related markers in the hippocampus were detected,respectively,Evaluate the correlation between VaD and ferroptosis;2.Take two groups of hippocampal tissue for transcriptomic sequencing,select a significantly differentially expressed target gene KLKB1 related to iron death,and verify its correlation with VaD in cells.KLKB1 is a gene encoding plasma prekallikrein(PK).Design and synthesize SiRNAs targeting KLKB1 knockdown,and transfect them into PC12 cells,A cell model using oxygen and glucose deprivation(OGD)to treat cells to induce VaD was divided into four groups: Blank group,OGD group,siCtrl+OGD group,and siKLKB1-3+OGD group.The levels of ferroptosis related markers in each group were measured: iron,reactive oxygen species(ROS),lipid peroxide(LPO)Glutathione Peroxidase 4(GPX4)and long chain acyl CoA synthase 4(ACSL4)were compared.Result:1.In the hippocampal tissue of the rat model,compared to the sham-operated group,the VaD group had significant changes in ferroptosis related markers,with significant increases in iron,ROS,LPO,and ACSL4 content,and significant decreases in GPX4content;2.Transcriptomic sequencing revealed that KLKB1 was significantly elevated in the hippocampus of the VaD rat model and correlated with ferroptosis;3.In the PC12 cell model,compared to the Blank group,the contents of iron,ROS,LPO,and ACSL4 in the OGD group and the siCtrl+OGD group increased significantly,while the activity of GPx enzyme and the content of GPX4 decreased significantly.There was no significant change in the levels of ferroptosis related markers in the siKLKB1-3+OGD group.The knockdown KLKB1 inhibited iron accumulation,oxidative stress,lipid peroxidation,and peroxidase reduction In the PC12 cell model.Conclusion:1.Ferroptosis is involved in the pathogenesis of VaD rat models;2.Significantly elevated KLKB1 induces ferroptosis in VaD rat models;3.Knock Down KLKB1 inhibits ferroptosis in PC12 cells,and KLKB1 may be a promising target for the treatment of VaD.