Abstract
Purpose::
The aim of this study was to identify the presence of retinoid acid receptors on cultured human scleral fibroblasts and the effect of the retinoic acid (RA) on regulation of cell growth.
Methods::
Human scleral fibroblasts from three donators were isolated and cultured in Dulbecco Modified Ealge’s Medium with cells from the third or fifth generation used for analysis. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was used to detect the expression of retinoid acid receptor subtypes in the fibroblasts. RA was added to the culture medium separately at concentration of 0.01nM,0.1nM,1nM,10nM, and 100nM. The cells were counted and statistically analyzed six days after being treated by RA. Each strain of the cells was examined three times.
Results::
The cultured fibroblasts mainly showed a bipolar or spindle-shaped morphology with the average time of 2 - 3 days for division. RT-PCR also showed mRNA expression of six subtypes of RA receptors (RARα, RARß, RARγ, RXRα, RXRß, and RXRγ). The proliferation of scleral fibroblasts was inhibited by 2.2%, 17.6%, 37.6%, 43.8%, 63.2% following the treatment with 0.01nM, 0.1nM, 1nM, 10nM and 100nM of RA, respectively. Cell proliferation in RA-treated samples reduced significantly compared to the control samples (p < 0.05) when the RA concentration exceeded 0.1nM.
Conclusions::
Six retinoid acid receptor subtypes are present in cultured human scleral fibroblasts and the growth of scleral fibroblasts was inhibited significantly by retinoic acid. These findings indicate that the sclera is a potential site of action for the retinoid acid during progression of myopia.
Keywords: myopia • retinoids/retinoid binding proteins • sclera