Liyan Chen

Institute of Molecular and Cell Biology · Functional Proteomics Laboratory

Metabolomics, the identification and quantitation of metabolites in a system, have been applied to identify new biomarkers or elucidate disease mechanism. In this review, we discussed the application of metabolomics in several ocular diseases and recent developments in metabolomics regarding tear fluids analysis, data acquisition and processing.

Data independent acquisition mass spectrometry (DIA-MS) coupled with liquid chromatography is a promising approach for rapid, automatic sampling of MS/MS data in untargeted metabolomics. However, during DIA-MS the wide isolation window generates spectra containing a mixed population of fragment ions together with their precursor ions. This precurso...

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes and the leading cause of visual impairment in working-age adults. Diabetic patients often develop DR despite appropriate control of systemic risk factors, suggesting the involvement of other pathogenic factors. We hypothesize a plasma metabolic signature of DR that...

Bacterial infection following implantation of an artificial corneal scaffold is a serious complication. Conventional antibiotic prophylaxis, which includes topical vancomycin application, is limited by low bioavailability, high dosing requirement, and poor patient compliance. The ideal option to overcome these issues is an antibiotic-eluting cornea...

Artificial cornea transplantation, keratoprosthesis, improves vision for patients at high risk of failure with human cadaveric cornea. However, post-operative infection can cause visual loss and implant extrusion in 3.2–17% of eyes. Long-term vancomycin drops are recommended following keratoprosthesis to prevent bacterial keratitis. Evidence, thoug...

"Dry eye" is a multi-factorial inflammatory disease affecting ocular surface caused by hyperosmolarity. Recent research efforts on dry eye have been directed towards biomarker discovery for diagnosis, response to treatment and disease mechanisms. This study employed a spontaneously immortalised normal human conjunctival cell line, IOBA-NHC as a mod...

The tears, a critical body fluid of the surface of the eye, contain an unknown number of molecules including proteins/peptides, lipids, small molecule metabolites, and electrolytes. There have been continued efforts for exploring the human tear proteome to develop biomarkers of disease. In this study, we used the high speed TripleTOF 5600 system as...

The tear film overlying the epithelial cells of the eye's surface is vital to visual function, and its composition is reflective of ocular surface health. The ultrasmall volume of tears poses challenges in its analysis, contributing to the limited number of reports on the tear metabolome. In addition, using a standard clinical method of tear collec...

Understanding the molecular mechanisms of antimicrobial peptide-membrane interactions is crucial in predicting the design of useful synthetic antimicrobial peptide analogues. Defensins are small (3-5 kDa) cysteine-rich cationic proteins which constitute the front line of host innate immunity. In this study, a series of eight 10 AA C-terminal analog...

The purpose of this study was to examine the effects of structural parameters of peptides on their oxidation by DMSO, including location of cysteine, effect of adjunct group participation, molecular hydrophobicity, steric hindrance or the accessibility of thiol group and peptide conformation, on oxidation rates, dimer formation and associated side...