Purchase this article with an account.
Abid Ali Ahmad, Elahé Crockett, Qi Wang, Julia V Busik; The role of miRNA-15a in the regulation of VEGF and angiogenesis pathway in diabetic retinopathy. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):2310.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
We have previously demonstrated that diabetes-induced down regulation of miRNA-15a in the retina promotes inflammation through up regulation of its direct target, the central enzyme of sphingolipid metabolism, acid sphingomyelinase. Recently it was demonstrated that VEGF-A is also a direct target of miRNA15a/16. To gain a more thorough understanding of the beneficial effects of miRNA-15a in inhibiting inflammation and angiogenesis in diabetic retina and retinal cells, this study was undertaken to further elucidate the role of miRNA-15a in the angiogenesis pathway in diabetic retinopathy.
The effect of miRNA-15a on VEGF-A mRNA and protein levels in human retinal pigment epithelial (HRPE) cells exposed to normal and high glucose (NG, HG) was evaluated by real time-PCR and ELISA, respectively. mRNA from HRPE cells transfected with mimic15a or mimic control was analyzed using Human Angiogenesis PCR Array.
VEGF-A mRNA expression in HRPE cells increased from .0033±5.23E-05 in NG to .0056±9.48E-04 in HG. Mimic15a down regulated VEGF-A mRNA expression (NG=0.0022±8.61E-05, p<.0001; HG=0.0035±4.49E-04, p=.0477). VEGF-A protein expression was 345±32.91pg/ml in NG and 422±7.19pg/ml in HG. Mimic-15a decreased VEGF-A protein expression (NG=301.13±22pg/ml, p=.0477; HG=373.14±57.8pg/ml, p=.0489). Inhibition of miRNA-15a showed the opposite effect. VEGF mRNA expression was increased by inhibitor 15a (NG=0.0058±.0012, p=.0239; HG=0.0065±5.03E-04, p=.003). VEGF protein expression increased to 532.78±57.28 pg/ml in NG, (p=.0339), and 586.31±28.44 pg/ml in HG, (p=.0463). Furthermore, HG inversely regulated miRNA-15a and VEGF expression in HRPE cells. VEGF secretion was induced in HRPE cells subjected to HG and overexpression of miRNA-15a by mimic15a inhibited this effect. PCR array data showed that overexpression of miRNA-15a led to 60 human angiogenesis related genes displaying ≥2.0 fold down-regulation.
Our data corroborates the finding that VEGF-A is regulated by miRNA-15a. The high number of angiogenesis genes down regulated by overexpression of miRNA-15a potentially points to a central role for miRNA-15a in the human angiogenesis pathway and a potential to use miRNA-15a as a therapeutic target for Diabetic Retinopathy.
This PDF is available to Subscribers Only