Abstract
Purpose : To compare the degree of saturation and fatty acid chain length of major lipid classes of meibum and tears in symptomatic versus asymptomatic contact lens wearers.
Methods : Tears and meibum were collected from 42 contact lens wearers (18 male; 24 female) with a median age of 24 years. Participants were classified as symptomatic or asymptomatic contact lens wearers based on CLDEQ-8 questionnaire scores. Lipid analysis was performed using chip-based nanoelectrospray ionization source coupled with hybrid linear ion trap-triple quadruple mass-spectrometry. Lipids (236 species) from wax esters (WE), cholesterol esters (CE), triacyl glycerides (TAG), (O-acyl)-ω-hydroxy fatty acids (OAHFA), phosphatidylcholines (PC), phosphatidylethanolamines (PE), phosphatidylserines (PS), sphingomyelins (SM), lysophosphatidylcholines (LPC) and lysophosphatidylethanolamines (LPE) were compared between symptomatic and asymptomatic contact lens wearers. Lipids were classified as saturated (SFA), mono-unsaturated (MUFA) or poly-unsaturated (PUFA) fatty acids and long-chain fatty acids (LCFA) or short-chain fatty acids (SCFA).
Results : Fifty percent (n=21) of the study subjects were symptomatic contact lens wearers. In comparison to asymptomatic contact lens wearers, meibum of symptomatic wearers had higher concentrations of PUFA in CE (7.2 ± 4.2%; p<0.05) and TAG (14.4 ± 5.9%; p< 0.05); while the tears had higher concentrations of PUFA in CE (14.7 ± 4.2%; p<0.05), TAG (5.8 ± 0.0%; p< 0.05), LPE (6.1 ± 8.7%; p<0.05), and OAHFA (27.4 ± 0.4%, p<0.001). The meibum of symptomatic contact lens wearers also had higher concentrations of LCFA in WE (7.5 ± 6.4%; p<0.05), CE (13.8 ± 0.6%; p<0.05) and LPE (5.6 ± 0.6%, p<0.05). Greater concentrations of LCFA in WE (12.2% ± 6.7%; p<0.05), CE (25.6 ± 1.6%; p<0.001) and OAHFA (24.1 ± 0.7%; p<0.001) were observed in the tears of symptomatic lens wearers.
Conclusions : Symptomatic lens wearers had higher levels of PUFA and LCFA in meibum and tears, that could potentially alter tear film viscoelasticity and increase tear evaporation. PUFAs are susceptible to peroxidation. Metabolism of PUFAs such as arachidonic acid act as precursors of inflammatory mediators which may also influence symptomatology.
Methods : Tears and meibum were collected from 42 contact lens wearers (18 male; 24 female) with a median age of 24 years. Participants were classified as symptomatic or asymptomatic contact lens wearers based on CLDEQ-8 questionnaire scores. Lipid analysis was performed using chip-based nanoelectrospray ionization source coupled with hybrid linear ion trap-triple quadruple mass-spectrometry. Lipids (236 species) from wax esters (WE), cholesterol esters (CE), triacyl glycerides (TAG), (O-acyl)-ω-hydroxy fatty acids (OAHFA), phosphatidylcholines (PC), phosphatidylethanolamines (PE), phosphatidylserines (PS), sphingomyelins (SM), lysophosphatidylcholines (LPC) and lysophosphatidylethanolamines (LPE) were compared between symptomatic and asymptomatic contact lens wearers. Lipids were classified as saturated (SFA), mono-unsaturated (MUFA) or poly-unsaturated (PUFA) fatty acids and long-chain fatty acids (LCFA) or short-chain fatty acids (SCFA).
Results : Fifty percent (n=21) of the study subjects were symptomatic contact lens wearers. In comparison to asymptomatic contact lens wearers, meibum of symptomatic wearers had higher concentrations of PUFA in CE (7.2 ± 4.2%; p<0.05) and TAG (14.4 ± 5.9%; p< 0.05); while the tears had higher concentrations of PUFA in CE (14.7 ± 4.2%; p<0.05), TAG (5.8 ± 0.0%; p< 0.05), LPE (6.1 ± 8.7%; p<0.05), and OAHFA (27.4 ± 0.4%, p<0.001). The meibum of symptomatic contact lens wearers also had higher concentrations of LCFA in WE (7.5 ± 6.4%; p<0.05), CE (13.8 ± 0.6%; p<0.05) and LPE (5.6 ± 0.6%, p<0.05). Greater concentrations of LCFA in WE (12.2% ± 6.7%; p<0.05), CE (25.6 ± 1.6%; p<0.001) and OAHFA (24.1 ± 0.7%; p<0.001) were observed in the tears of symptomatic lens wearers.
Conclusions : Symptomatic lens wearers had higher levels of PUFA and LCFA in meibum and tears, that could potentially alter tear film viscoelasticity and increase tear evaporation. PUFAs are susceptible to peroxidation. Metabolism of PUFAs such as arachidonic acid act as precursors of inflammatory mediators which may also influence symptomatology.
| Original language | English |
|---|---|
| Pages | 1-1 |
| Number of pages | 1 |
| Publication status | Published - 13 Jul 2018 |
| Externally published | Yes |