Rohit Athira, Willcox Mark D P, Stapleton Fiona
*PhD, FAAOSchool of Optometry and Vision Science, the University of New South Wales, Sydney, New South Wales (AR, MDPW, FS); and Brien Holden Vision Institute, Sydney, New South Wales, Australia (AR).
Optom Vis Sci. 2016 Oct;93(10):1203-1209. doi: 10.1097/OPX.0000000000000947.
To establish the effect of lipid supplements on tear lipid biochemistry and their influence on lens wear comfort in habitual lens wearers.
Forty habitual soft contact lens wearers were recruited to a double-masked, randomized crossover trial. An emulsion drop containing phosphatidylglycerol (Systane Balance; Alcon) and a liposomal spray containing phosphatidylcholine (Tears again; BioRevive) along with saline placebos were used three times a day for 14 days with 48 hours of washout between each intervention. The Contact Lens Dry Eye Questionnaire categorized participants into symptomatic and asymptomatic wearers. Ocular comfort was measured using the Ocular Comfort Index. Basal tears (15 μl from each eye) were collected with lenses in situ and assayed for the concentration and activity of phospholipase (sPLA2) and the concentration of a malondialdehyde (MDA). Electrospray ionization mass spectrometry characterized the tear lipidome.
Neither of the lipid supplements improved lens wear comfort compared to baseline. The spray treatment did not affect the concentration of the majority of lipid classes either at day 1 or at day 14. Both the lipid and placebo drops resulted in increased concentration of several lipid classes after day 1 of use, but by day 14, the concentration of most of the lipid classes had returned to baseline levels. With the lipid spray, sPLA2 activity (0.38 ± 0.2 vs. 0.73 ± 0.6 mmol/min/ml, p = 0.03) and lysophosphatidylethanolamine (LPE) (1.3 ± 0.5 vs. 2.7 ± 0.07 pmol/μl, p = 0.02) were higher in the symptomatic group compared to asymptomatic group at day 1 but not at day 14. The lipid drop resulted in increased LPE concentration in symptomatic wearers at day 1 (1.7 ± 0.3 vs. 2.4 ± 0.3 pmol/μl, p = 0.01) and at day 14 (1.7 ± 0.4 vs. 2.5 ± 0.5 pmol/μl, p = 0.04). Ocular comfort was inversely proportional to the level (r = -0.21, p = 0.007) and activity of sPLA2 (r = -0.20, p = 0.01). There was an association between sPLA2 and LPC (r = 0.41, p < 0.001) and LPE (r = 0.40, p = 0.001), and a negative association with (O-acyl)-ω-hydroxy fatty acids (OAHFAs) (r = -0.30, p = 0.03) in tears.
Contact lens wear comfort was associated with sPLA2 concentration and activity in tears. Lipid biochemistry was transiently influenced by exogenous supplements. Although the specific supplement formulations tested did not differ from placebo in this study, the results do suggest a potential role for lysophospholipids and OAHFAs in modulating symptoms during contact lens wear.
确定脂质补充剂对泪液脂质生物化学的影响及其对习惯性佩戴隐形眼镜者镜片佩戴舒适度的影响。
招募40名习惯性佩戴软性隐形眼镜者参与一项双盲、随机交叉试验。含磷脂酰甘油的乳剂滴剂（思然平衡；爱尔康）、含磷脂酰胆碱的脂质体喷雾（再润眼；生物复兴）以及生理盐水安慰剂，每天使用3次，持续14天，每次干预之间有48小时的洗脱期。使用隐形眼镜干眼问卷将参与者分为有症状和无症状佩戴者。使用眼舒适度指数测量眼部舒适度。在佩戴镜片的情况下从每只眼睛收集15μl基础泪液，检测磷脂酶（sPLA2）的浓度和活性以及丙二醛（MDA）的浓度。电喷雾电离质谱法对泪液脂质组进行表征。
与基线相比，两种脂质补充剂均未改善镜片佩戴舒适度。喷雾处理在第1天和第14天均未影响大多数脂质类别的浓度。脂质滴剂和安慰剂滴剂在使用第1天后均导致几种脂质类别的浓度增加，但到第14天，大多数脂质类别的浓度已恢复到基线水平。使用脂质喷雾时，有症状组在第1天的sPLA2活性（0.38±0.2对0.73±0.6 mmol/min/ml，p = 0.03）和溶血磷脂酰乙醇胺（LPE）（1.3±0.5对2.7±0.07 pmol/μl，p = 0.02）高于无症状组，但在第14天并非如此。脂质滴剂在第1天（1.7±0.3对2.4±0.3 pmol/μl，p = 0.01）和第14天（1.7±0.4对2.5±0.5 pmol/μl，p = 0.04）使有症状佩戴者的LPE浓度增加。眼部舒适度与sPLA2的水平（r = -0.21，p = 0.007）和活性（r = -0.20，p = 0.01）呈负相关。泪液中sPLA2与LPC（r = 0.41，p < 0.001）和LPE（r = 0.40，p = 0.001）之间存在关联，与（O-酰基）-ω-羟基脂肪酸（OAHFAs）呈负相关（r = -0.30，p = 0.03）。
隐形眼镜佩戴舒适度与泪液中sPLA2的浓度和活性相关。外源性补充剂对脂质生物化学有短暂影响。尽管本研究中测试的特定补充剂配方与安慰剂没有差异，但结果确实表明溶血磷脂和OAHFAs在调节隐形眼镜佩戴期间的症状方面可能发挥作用。
