Proteomic study of aqueous humour in diabetic patients with cataracts by TMT combined with HPLC-MS/MS

Comparative Proteomic Analysis of Aqueous Humor Reveals Biochemical Disparities in the Eyes of High Myopic Patients

Myopia accounts for a significant proportion of visual lesions worldwide and has the potential to progress toward pathological myopia. This study aims to reveal the difference in protein content in aqueous humor between high myopic and nonhigh myopic patients, as well as better understand the dysregulation of proteins in myopic eyes. Aqueous humor was collected for liquid chromatograph mass spectrometer (LC/MS) analysis from 30 individual eyes that underwent phacoemulsification and intraocular lens (IOL) implantation. Results showed that a total of 190 differentially expressed proteins were identified, which revealed their involvement in cell metabolism, immune and inflammatory response, and system and anatomical structure. Further analysis focused on 15 intensively interacted hub proteins, encompassing functions related to complement cascades, lipoprotein metabolism, and fibrin biological function. Subsequent validations demonstrated elevated levels of APOE (apolipoprotein E), C3 (complement 3), and AHSG (α-2-HS-glycoprotein) in the high myopia group (31 eyes of cataracts and 45 eyes of high myopia with cataracts). AHSG had a significant positive correlation with axial length in high myopic patients, with good efficacy in distinguishing between myopic and nonmyopic groups. AHSG may be a potential indicator of the pathological severity and participator in the pathological progress of high myopia. This study depicted differential expression characteristics of aqueous humor in patients with high myopia and provided optional information for further experimental research on exploring the molecular mechanisms and potential therapeutic targets for high myopia. Data are available via ProteomeXchange with the identifier PXD047584.

Recurrence of macular edema in patients with branch retinal vein occlusion: a proteomic study

BACKGROUND

Branch retinal vein occlusion (BRVO) is a common retinal vascular disease leading to severe vision loss and blindness. This study aimed to investigate and reveal the pathophysiological mechanisms underlying macular edema (ME) recurrence in patients with BRVO through a proteomic approach.

METHODS

We detected proteins in the aqueous humor of 14 untreated, four refractory, and four post-operative patients with BRVO-ME and 12 age-matched cataract controls using four-dimensional label-free proteomic and bioinformatics analyses.

RESULTS

In total, 84 proteins exhibited significant differential expression between the BRVO and control samples (fold change [FC] ≥ 1.2 and adjusted p-value < 0.05). Compared to the control group, 43 and 41 proteins were upregulated and downregulated, respectively, in the BRVO group. These proteins were involved in cell adhesion, visual perception, retina homeostasis, and platelet activation. Several significantly enriched signaling pathways included complement and coagulation cascades and platelet activation. In the protein-protein interaction networks generated using the search tool for retrieval of interacting genes (STRING), the fibrinogen alpha chain and fibrinogen beta chain constituted a tightly connected cluster. Many common protein expression trends, such as the fibrinogen alpha chain and fibrinogen beta chain, were observed in both the recurrent and refractory groups. Differentially expressed proteins in the two groups were involved in complement activation, acute-phase response, platelet activation, and platelet aggregation. Important signaling pathways include the complement and coagulation cascades, and platelet activation. Protein-protein interaction analysis suggested that the fibrinogen alpha chain and fibrinogen beta chain constituted a tightly connected cluster. The expression of some differentially expressed proteins shared by the BRVO and the recurrent and refractory groups was reversed in the post-operative group.

CONCLUSIONS

Our study is the first to analyze the proteomics of recurrent, refractory, and post-operative groups treated for BRVO-ME, and may potentially provide novel therapeutic interventions for the recurrence of ME.