Alkali burn causes aldehyde dehydrogenase 3A1 (ALDH3A1) decreasein mouse cornea

[摘要] Purpose: Aldehyde dehydrogenase 3A1 (ALDH3A1) is the most abundantsoluble protein component in the mouse cornea, produced mainly bycorneal epithelial cells. High levels of ALDH3A1 in cornea contribute tomaintenance of a stable an d transparent corneal structure. Alkali burnis a common damage to the corneal surface, which produces an alkalinehydrolysis of matrix proteins and induces an inflammatory reaction. Ourstudy was intended to detect changes in ALDH3A1 expression after cornealalkaline burn.Methods: To address this issue we employed RTQ-PCR to monitor thetranscriptional change of ALDH3A1 after alkali burn. We used zymographyto test enzyme activity changes of ALDH3A1 in the alkali burn cornea;And SDS-PAGE and mass spectrometry technology were used to verifyprotein content changes and to identify ALDH3A1 protein.Results: Using zymography, ALDH3A1 enzymic activity was observed todecrease immedialtely after corneal alkali burn and the levels recoveredfollowing healing. Proteins extracted from alkali burned corneas, whenrun on SDS-PAGE, showed the same sized band (about 54 kDa, which is themolecular weight of ALDH3A1) but in much smaller quantity, compared tonormal corneas. This result was further verified by mass spectrometryfingerprinting of the in-gel lysis product. An immediate decrease ofALDH3A1 transcription after alkali burning of the cornea was also foundusing RTQ-PCR. This level of transcription was gradually restored duringhealing.Conclusions: Alkali burn of the corneal surface caused a rapiddecrease of ALDH3A1 in the corneal at both the RNA and protein levels,which leads to the loses of the protective component of the cornealsurface and makes it vulnerable to further damage. The ALDH3A1 level inthe cornea gradually recovered during the healing process. Use of ananti-oxidation reagent as a treatment ingredient for alkali burn of thecorneal surface could compensate for the decrease of anti-oxidationprotection potential caused by ALDH3A1 loss.

[学科分类] 生物化学/生物物理