Abstract
Purpose::
To compare the lipocalin : total protein ratios present in the tears of a group of asymptomatic and symptomatic dry eyed post menopausal (PM) women
Methods::
31 healthy PM females (>50 years of age), who were non-contact lens wearers and not on Hormone Replacement Therapy, were categorized as being symptomatic (mild, moderate or severe) or asymptomatic (no symptoms or trace) of dry eye (DE) based on their responses to a single-item score dry eye questionnaire (SIDEQ). Total tear protein was quantified with BioRad’s DC protein assay. Western blotting was performed to determine the amount of lipocalin (using a pooled tear standard as there is no commercially available lipocalin standard) present in symptomatic and asymptomatic PM women
Results::
SIDEQ responses revealed 15 symptomatic (DE; 60.7 ± 8.8 yrs; mild=6, moderate =9, severe =0) and 16 asymptomatic (NDE; 59.4 ±6.9 yrs; no symptoms=12, trace=4) participants. Lipocalin ratios (lipocalin/total protein; mean ± SD) in asymptomatic PM women were: no symptoms = 0.197±0.06; trace = 0.185 ±0.06 and in symptomatic PM women were: mild = 0.176±0.04; moderate= 0.144±0.06. There was no significant difference seen in the lipocalin ratios between the two groups of participants (p>0.05), and a weak negative correlation between the symptom score and the lipocalin ratios was determined (r=-0.32; p=0.07)
Conclusions::
Our data clearly shows a trend of decreasing tear lipocalin ratios in PM women as their symptoms of dry eye increase. Further research is required to study a larger sample, particularly one including those with severe dry eye symptoms
Keywords: cornea: tears/tear film/dry eye • protein structure/function • lacrimal gland