Sex Differences in Meibomian Gland Triglycerides

Abstract

Abstract: : Purpose: To determine the composition of meibomian gland lipids in male and female humans. Methods: Meibomian gland secretions were collected from subjects (13 males and 12 females) and lipids separated into groups by solid phase extraction (SPE). Lipid groups were further separated by high pressure liquid chromatography (HPLC) and individual lipid types determined and compared to standards. Results: We observed a difference in nonpolar lipids; there was a distinct sex difference in meibomian gland triglycerides (TG). The male TG mean was 2.3% plus or minus 1.7% (range 0.14% to 4.8%) (n=11) of the total meibomian lipid. In contrast female TG mean was 61.8% plus or minus 38.5% (range 6.3% to 98.6%) (n=10). Conclusions:There was a distinct sex difference in TG between males and females. The importance of this difference could be that high TG levels in females results in greater stability in the tear film lipid layer. In contrast TG may be more susceptible than other lipids to degradation by enzymes such as those from bacteria. These results suggest that sex differences in tear film lipid compostion should be considered when evaluating and treating patient signs.

Keywords: lipids