ATRA stimulates the expression of MMP2 and TGF-β2 via RDH5 in retinal pigment epithelium cells

Abstract

Background To investigate the effect of all-trans retinoic acid (ATRA) on retinol dehydrogenase 5 (RDH5), matrix metalloproteinase-2 (MMP2) and transforming growth factor-β2 (TGF-β2) transcription levels, and the effect of RDH5 on MMP-2 and TGF-β2. Methods After ARPE-19 cells intervened with gradient concentrations of ATRA (0–20 µM) for 24 h, flow cytometry was used to detect the proliferation and apoptosis of cells in each group, and qRT-PCR was used to detect RDH5, MMP2 and TGF-β2 mRNA expression. Then, after ARPE-19 cells transfected with three different siRNA targets for 48 h, the RDH5 knockdown efficiency of each group and expression of MMP-2 and TGF-β2 mRNA within them was detected by qRT-PCR. Results Flow cytometry showed that ATRA could inhibit the proliferation of and promote the apoptosis of RPE cells, and the difference of apoptosis was statistically significant when the ATRA concentration exceeded 5 µM and compared with the normal control group (P = 0.027 and P = 0.031, respectively). qRT-PCR results showed that ATRA could significantly inhibit the expression level of RDH5 mRNA (P < 0.001), and promote the expression of MMP2 and TGF-β2 mRNA (P = 0.03 and P < 0.001, respectively) in a dose-dependent manner, especially when treated with 5 µM ATRA. The knockdown efficiency of RDH5 siRNA varies with different targets, among which RDH5 siRNA-435 had the highest knockdown efficiency, i.e., more than 50% lower than that of the negative control group (P = 0.02). When RDH5 was knocked down for 48 h, the results of qRT-PCR showed that the expressions of MMP-2 and TGF-β2 mRNA were significantly up-regulated (P < 0.001). Conclusions ATRA inhibited the expression of RDH5 and promoted myopic signaling factors MMP2 and TGF-β2, and further RDH5 knockdown significantly upregulated MMP-2 and TGF-β2. These findings suggest that RDH5 may be involved in myopia development mediated by ATRA.

RDH12-associated retinal degeneration caused by a homozygous pathogenic variant of 146C>T and literature review

“…R etinol dehydrogenase 12 (RDH12) is a nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)dependent retinaldehyde reductase that is specifically expressed in photoreceptor cells and participates in the visual cycle [1][2] . In the visual cycle, a series of reactions are involved in the transport mechanisms between the retinal pigment epithelium (RPE) and photoreceptor cells, in which different members of retinol dehydrogenase play important roles [3][4] . It has the highest activity with all-trans retinal production.…”