Alterations In GABA And Glutamate Pathways In The Prefrontal Cortex In Depressed Patients

Background:Depressionis very common and has serious consequences.Suicidal behavior is one of the typical depressive symptoms,it can happen throughout the entire stage of the depression.Depression also affects up to 50%of patients with Alzheimer's disease(AD).Previous study which were focused on the depression patients showed the neurotransmitter ?-aminobutyricacid(GABA)and glutamic acid(glutamate)and their associated pathways in the prefrontal cortex are related to the pathogenesis of depression.However,these studies with depression patients did not group the patients in a more detailed and better way according to the depressive symptoms,we still know very little about how the GABA and glutamate pathways affected in the different group of depression.Objective:To study the alterations in GABA and glutamate pathways in the prefrontal cortex in mood disorder patients.Methods:The expression of molecules of GABA and glutamate pathways by qPCR in the postmortem anterior cingulate cortex(ACC)and/or dorsolateral prefrontal cortex(DLPFC),in three different dataset,were detected:1)the non-suicidal elder depression patients with their matched control subjects;2)the suicidal depression,non-suicidal depression and their matched controls;3)depressed AD,non-depressed AD and their matched controls.Results:33 target genes were detected in the DLPFC and ACC separately,only GABRB2 and PSD-95 mRNA levels were significantly lower in the non-suicide elder depressed patients compared to control group in the ACC,but no change of any level of gene transcription in the DLPFC.In the suicidal depression patients,the transcription levels of 13 target genes were significantly increased compared to control subjects.In depressed AD patients,GABRA5 mRNA level was significantly decreased,VGluT1 mRNA levels were positively correlated to the Cornell score for depression severity.Conclusion:The different symptoms of depression,prefrontal GABA and glutamate pathway presents a completely different performance dysfunction,and GABA and glutamate alterations seem thus to be related to suicide rather than to depression...