Abstract
Purpose :
To investigate the effects of loss of sphingosine-1-phosphate receptor 3 (S1PR3) in the development of neovascularization in corneal stroma in mice. S1P is one of the major lipid mediators produced from cell membrane components, and modulates cell behaviors through binding to specific receptor family members after extracellularly transported.
Methods :
Corneal neovascularization from the limbal vessels was induced by cauterization of the central cornea of an eye by using of C57BL/6 (WT) mice (n = 40) and S1PR3 null (KO) mice (n = 44) by using a disposable tool of Optemp. Mice were killed at day 3, 7 and 14. (1) The eye was then enucleated, processed for cryosectioning and paraffin section and were examined by using immunohistochemistry for neovascularization. (2) Expression of angiogenic growth factors and inflammatory cell markers were examined in RNA samples derived from day3 corneal samples and uninjured corneas by using TaqMan real time-RT-PCR.
Results :
(1) S1PR3 was markedly detected by immunostaining in corneal and limbal epithelia of a WT mouse. After cauterization S1PR3 expressed in not only corneal epithelium but also in neovascularized tissue of WT mouse. The length of the neovascularization from the limbus was significantly less in KO mice as compared with WT mice at day 3, 7 and 14 as revealed by CD31 immunostaining. (2) Expression of mRNAs of VEGF-A and alpha-smooth muscle actin was significantly suppressed by S1PR3 gene deletion as compared with a WT cornea at day 3 post-cautarization.
Conclusions :
Endogenous S1P modulates expression of angiogenic cytokines and is involved in development of corneal neovascularization through S1PR3 in mice.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.