Abstract
Purpose :
To determinate the expression of Lanosterol Synthase (LS) in human cataractous lenses and evaluate the relationship with the degree of opacity and their association with α A crystallin protein.
Methods :
20 cataractous lenses were obtained by SICS (Small Incision Cataract Surgery) from patients with cataract and were classified according to the LOCS III cataract score classification (LOCS II to V), Nigra cataracts were classified as a LOCS V, and control from normal eyes from eye bank (without cataract) were used.
Lenses were cryopreserved in RNAssist at -70 °C for Immunofluorescence and Confocal microscopy analysis and for protein isolation for Western Blot analysis.
Lanosterol synthase was localized by IF using OSC antibody and colocalized with Alpha A crystallin protein quantified as arbitrary units of fluorescence and normalized to a percent value using the control lenses as a base line. Fluorescence was quantified using Image J from NIH. Proteins were isolated as analyzed by WB and with Lanosterol Synthase antibody - OSC to corroborate the in-situ findings.
Results :
Lanosterol Synthase was founded in cataractous lenses mainly in the central nucleus area and their values were higher and over expressed in mature cataracts (LOCS V) in comparison with lower LOCS values and control lenses. Fluorescence values were 100±10 controls, 410±20 LOCS II, 930±24 LOCS III, 1100± 50 LOCS IV and 1400±100 LOCS V and Nigra cataracts.
Alpha A Crystallin was overexpressed in cataractous lenses in comparisons with controls and their values were 100±10 controls, 190±10 LOCS II, 445±100 LOCS III, 570±70 LOCS IV and 670±50 LOCS V and Nigra.
Western Blot confirmed the overexpression of Lanosterol synthase in cataracts lenses with a progressive increase according to lens opacity.
Conclusions :
Lanosterol Synthase was overexpressed in cataractous lenses in a magnitude of more than 10 times higher in seriously dense cataracts (Nigra and LOCS V) in comparison than normal lenses and Alpha A Crystallin exhibited a similar profile. As a salient conclusion a compensatory mechanism of over expression of this proteins in cataractous lenses is observed as a response to the oxidative stress as a compensatory mechanism to delay the cataract formation.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.