VEGF-R2/Caveolin-1 Pathway of Undifferentiated ARPE-19 Retina Cells: A Potential Target as Anti-VEGF-A Therapy in Wet AMD by Resvega, an Omega-3/Polyphenol Combination

Abstract

Age-related macular degeneration (AMD) is one of the main causes of deterioration in vision in adults aged 55 and older. In spite of therapies, the progression of the disease is often observed without reverse vision quality. In the present study, we explored whether, in undifferentiated ARPE-19 retinal cells, a disruption of the VEGF receptors (VEGF-R)/caveolin-1 (Cav-1)/protein kinases pathway could be a target for counteracting VEGF secretion. We highlight that Resvega®, a combination of omega-3 fatty acids with an antioxidant, resveratrol, inhibits VEGF-A secretion in vitro by disrupting the dissociation of the VEGF-R2/Cav-1 complex into rafts and subsequently preventing MAPK activation. Moreover, DNA ChIP analysis reveals that this combination prevents the interaction between AP-1 and vegf-a and vegf-r2 gene promoters. By these pathways, Resvega could present a potential interest as nutritional complementation against AMD.

Resvega, a Nutraceutical Preparation, Affects NFκB Pathway and Prolongs the Anti-VEGF Effect of Bevacizumab in Undifferentiated ARPE-19 Retina Cells

“…We have previously been able to show that RGA supplementation was able to decrease VEGF secretion in an in vivo mouse model [ 18 ]. In undifferentiated human ARPE-19 retinal cells mimicking the cells affected by AMD [ 24 ], this nutraceutical formulation was also able to reduce the secretion of VEGF by approximately 20% after 24 h of treatment, without affecting cell viability [ 22 ]. Firstly, in this same human retinal cell model that is widely used to test the efficacy of anti-angiogenic compounds, we tested whether the anti-angiogenic effect of RGA lasted over time, increased or, on the contrary, decreased.…”

“…Once activated, it in turn triggers many intracellular signaling pathways. These include, in particular, the ERK1/2 pathway on which we have shown that RGA has an effect [ 22 ], but also other pathways, for instance the PI3K-AKT-mTOR pathway, which is crucial for cell survival, regulation of vasomotion and angiogenesis [ 27 , 28 ] In order to understand the impact of RGA on VEGF-A pathway through PI3K-AKT-mTOR, we investigated its effect on the expression of key proteins involved in the signaling cascade. Immunoblotting analysis revealed that RGA strongly decreases phosphorylation of c-RAF, in a concentration-dependent manner, as well as the protein expression of PI3K, AKT, mTOR and their respective phosphorylated forms ( Figure 2 A,B).…”

“…These new insights complement the full spectrum of action of RGA on signaling pathways, which we and others have recently begun to describe. We previously demonstrated that RGA, as anti-VEGF formulation, prevents activation of the MAPK signaling pathway in ARP19 cells [ 18 , 22 ]. In total, the RGA-mediated disruption of these two important angiogenesis signaling pathways (i.e., PI3K-AKT-mTOR and MAPK signaling pathways) likely lead a prolongation of anti-angiogenic properties of bevacizumab (Avastin ® ), an anti-VEGF often used to treat AMD ( Figure 7 ).…”

“…A potential molecular explanation was recently suggested by some authors showing that RGA could reduce inflammation [ 19 ] and oxidative stress [ 20 ], and, on the contrary, induce autophagy [ 21 ] in retinal cell models. Very recently, we have demonstrated that the ω-3 fatty acids/RSV combination interferes with the transcriptional regulation of genes coding both for VEGF-R2 and VEGF-A [ 22 ]. Nevertheless, the molecular mechanisms by which RGA prevents angiogenesis in retina cells is still unclear.…”

Caveolin-1 Down-Regulation Reduces VEGF-A Secretion Induced by IGF-1 in ARPE-19 Cells

“…Moreover, we found that that IGF-1-induced Erk phosphorylation is significantly decreased in ARPE-19 cells in which Cav-1 has been depleted. Since it has been reported that the MAP Kinase pathways controls VEGF-A stimulated secretion in RPE cells [10,25,26], Cav-1 depletion may prevent IGF-1-induced VEGF-A secretion by attenuating the Erk kinase signaling.…”