AIM:To find out the pathogenesis of dry eye disease(DED)and the possible mechanisms of available effective treatments.

METHOD:Here we employed a non-targeted technology, ultra-high performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry(UHPLC-Q-TOF-MS), to investigate metabolic characterizations for tear samples from 18 patients with DED upon drug or acupuncture treatment.

RESULTS:A total of 190 named metabolites were identified, which presented so far the broadest tear metabolome. Further analysis indicated a significantly distinct metabolomics profile among all patients, but very subtle metabolic differences upon drug or acupuncture treatment. On one hand, only six significantly changed metabolites were determined after drug treatment, five of which including inosine, monopalmitin, urate, propionylcarnitine, and nicotinamide were all increased and involved in inflammatory responses. On the other hand, merely four metabolites including alanine, serine, and homoserine were found to be significantly different. Further pathway analysis of those six and four significantly changed metabolites revealed that only one pathway, aminoacyl-tRNA biosynthesis was significantly influenced in acupuncture-treated patients, which were highly associated with the cause of the disease. The results here indicated acupuncture treatment may address the cause rather than the symptoms for dry eye disease, displaying partially better compared with drug treatment.

CONCLUSION: Collectively, this work extended our understanding on the key regulatory elements or pathways involved in the potential mechanisms of available effective treatments, and would be useful for providing novel potential targets and therapeutic strategies for DED.