Distribution of lanosterol synthase and lanosterol in cornea, lens and retina tissue of rats / 中华实验眼科杂志

ABSTRACT

Background Researches showed that triterpenoids,with a similar structure to lanosterol,has therapeutical effect on many systemic diseases,and lanosterol was determined to have a therapeutical effect on cataract recently.However,how the lanosterol plays effects on other eye diseases is still unelucidated.Understanding the distribution of lanosterol in ocular tissue is helpful for us to elucidate the relationship of lanosterol with eye diseases.Objective This study attempted to investigate the distribution of lanosterol synthase (LSS) and lanosterol in cornea,lens and retina tissue of rats and offer a basis for the targeting treatment of eye diseases.Methods Fifteen SPF male SD rats were sacrificed by excessive anesthesia to obtain the eyeballs.The relative expressions of LSS protein and gene in the cornea,lens and retina tissue of the rats were detected by Western blot and reverse transcription (RT)-PCR,respectively.Immunofluorescence staining technology was used to locate the distribution of LSS in cornea,lens and retina tissue.The contents of lanosterol in the cornea,lens and retina tissue were analyzed by liquid chromatograph mass spectrometer (LC-MS).Results No LSS protein and mRNA was expressed in the retinal tissue in normal rats.The mean relative expression of LSS protein in the lens and cornea was 0.43±0.05 and 0.25±0.03,respectively,showing a significant difference between them (t =-5.35,P＜ 0.01).The relative expression of LSS mRNA was 0.51 ±0.04 and 0.29 ±0.02 in the lens and cornea,respectively,with a stronger expression in the lens in comparison with the cornea (t =-8.34,P＜0.01).Immunofluorescence staining showed that LSS primarily located in corneal epithelial layer,stromal layer and endothelial layer as well as lens epithelial cells and shallow cortex layer and hardly expressed in retina,and no co-expression of LSS with the neuron marked by NeuN and the Müller cell marked by glutamine synthetase (GS) in retinal tissue.LC-MS analysis revealed that the contents of lanosterol in lens and cornea was (24.37 ±2.91) ng/mg and (5.31 ±0.58) ng/mg,respectively,with a significant difference between them (t =-11.13,P＜0.01).Conclusions LSS and lanosterol extensively distribute in cornea and lens of normal rats,but not in retina tissue.These results offer new strategies for the target treatment of relevant eye diseases.