Authors: Liu Aihua, Wang Liming, Lyu Yingjuan, Liu Wei, Li Xiaorong, Dong Lijie
To analyze the changes of protein expression in aqueous humor of patients with primary open angle glaucoma (POAG), and to explore the biological markers and potential therapeutic targets associated with disease occurrence.
A retrospective case-control study was adopted.Ten patients with age-related cataract and 10 patients with POAG combined with cataract.were collected at the Tianjin Medical University Eye Hospital from October 2016 to December 2017.In the process of surgery, 100 μl of aqueous humor were collected with 1 ml syringe and No.1 needle through the surgical access.Those proteins extracted from aqueous humor were analyzed by quantitative proteomic mass spectrometry.The differential significance test was performed by Maxquant significances A. The differential proteins of the two groups were screened and determined with the conditions of P<0.05 and difference multiple>2.The biological big data was annotated by the function of GO and KEGG.The study was approved by the Ethics Committee of the Tianjin Medical University Eye Hospital (No.2013KY[L]-10). Patients and their guardians all signed the informed consent.
Ninty-seven differential proteins were detected in this proteomic analysis, including 48 up-regulated proteins and 49 down-regulated proteins.GO analysis significantly differs in protein function involved in many aspects, some different proteins including lipopolysaccharide-binding protein (LBP), cluster of Differentiation 163(CD163), C-reactive protein (CRP), annexin A1 (ANXA1) were involved in inflammation; redox-related proteins were glutathione S-transferase P (GSTP1), thioredoxin (TXN), some different proteins related with cell adhesion movement were cartilage oligomeric matrix protein (COMP), desmocollin-2 (DSC2) and laminin subunit beta-2 (LAMB2); procollagen-lysine, 2-oxoglutarate 5-dioxygenase 1 (PLOD1), solid protein (tenascin, TNC) are associated with fibrosis; some different proteins related to nerve growth were reelin (RELN), semaphorin-3F(SEMA3F), semaphorin-4B(SEMA4B). Metabolism-related proteins included pyruvate kinase (PKM), carb oxypeptidase N subunit 2 (CPN2) and so on.KEGG analysis indicated that the expression of NrF2/ERK signaling pathway and TGF-β/NF-κB signaling pathway were different between the two groups.
The expression of GSTP1 and TXN in the aqueous humor of POAG is significantly decreased, which may regulate cell adhesion and activity and expression of extracellular matrix by regulating NrF2/ERK1/2 and TGF-β/NF-κB signaling pathways.GSTP1 and TXN may serve as a potential biomarker and therapeutic target of POAG.