Death-associated protein kinase 1 is associated with cognitive dysfunction in major depressive disorder

We previously showed that death-associated protein kinase 1(DAPK1)expression is increased in hippocampal tissue in a mouse model of major depressive disorde and is related to cognitive dysfunction in Alzheimer's disease.In addition,depression is a risk factor for developing Alzheimer's disease,as well as an early clinical manifestation of Alzheimer's disease.Meanwhile,cognitive dysfunction is a distinctive feature of major depressive disorder.Therefore,DAPK1 may be related to cognitive dysfunction in major depressive disorder.In this study,we established a mouse model of major depressive disorder by housing mice individually and exposing them to chronic,mild,unpredictable stressors.We found that DAPK1 and tau protein levels were increased in the hippocampal CA3 area,and tau was hyperphosphorylated at Thr231,Ser262,and Ser396 in these mice.Furthermore,DAPK1 shifted from axonal expression to overexpression on the cell membrane.Exercise and treatment with the antidepressant drug citalopram decreased DAPK1 expression and tau protein phosphorylation in hippocampal tissue and improved both depressive symptoms and cognitive dysfunction.These results indicate that DAPK1 may be a potential reason and therapeutic target of cognitive dysfunction in major depressive disorder.

Hypidone hydrochloride(YL-0919)ameliorates functional deficits after traumatic brain injury in mice by activating the sigma-1 receptor for antioxidation

Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury.