Table 9.

Metabolite differences in the tears of dry eye tears in comparison to control subjects.

Metabolites	Change in dry eye tears	Reference
Cholesterol/lipids	↓	Galbis-Estrada et al., 2014 [530]
N-Acetylglucosamine	↓	Galbis-Estrada et al., 2014 [530]
Glutamate	↓	Galbis-Estrada et al., 2014 [530]
Carnitine	↓	Galbis-Estrada et al., 2014 [542]
Taurine	↓	Nakatsukasa et al., 2011 [537]
Methionine	↓	Nakatsukasa et al., 2011 [537]
Arginine	↓	Nakatsukasa et al., 2011 [537]
Serotonin	↑	Chhadva et al., 2015 [549]
Total creatine	↑	Galbis-Estrada et al., 2014 [530]
Arginine + phosphoetanolamine	↑	Galbis-Estrada et al., 2014 [530]
Phenylalanine	↑	Galbis-Estrada et al., 2014 [530]
Choline/acetylcholine	↑	Galbis-Estrada et al., 2014 [530]
Choline	↑	Galbis-Estrada et al., 2014 [530]
Glucose	↑	Galbis-Estrada et al., 2014 [530]
Amino-n-butyrate	↑	Galbis-Estrada et al., 2014 [530]
Diadenosine polyphosphates (Ap4A and Ap5A)	↑	Carracedo et al., 2010 [547] Peral et al., 2006 [548]