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bioRxiv · 10.1101/2024.01.15.575719

Polydopamine Nanoparticles as Mimicking RPE Melanin for the Protection of Retinal Cells Against Blue Light-Induced Phototoxicity

Kwon, Y.-S.·Zheng, M.·Smirnov, A. I.·Han, Z.
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Abstract

Exposure of the eyes to blue light can induce the overproduction of reactive oxygen species (ROS) in the retina and retinal pigment epithelium (RPE) cells, potentially leading to pathological damage of age-related macular degeneration (AMD). While the melanin in RPE cells absorbs blue light and prevents ROS accumulation, the loss and dysfunction of RPE melanin due to age-related changes may contribute to photooxidation toxicity. Herein, we present a novel approach utilizing a polydopamine-replenishing strategy via a single-dose intravitreal (IVT) injection to protect retinal cells against blue light-induced phototoxicity. To investigate the effects of overexposure to blue light on retinal cells, we created a blue light exposure Nrf2-deficient mouse model, which are susceptible to light-induced retinal lesions. After blue light irradiation, we observed retina degeneration and an overproduction of ROS. The Polydopamine-replenishing strategy demonstrated effectiveness in maintaining retinal structural integrity and preventing retina degeneration by reducing ROS production in retinal cells against the phototoxicity of blue light exposure. Our findings highlight the potential of polydopamine as a simple and effective replenishment for providing photoprotection against high-energy blue light exposure. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC="FIGDIR/small/575719v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@1e60e66org.highwire.dtl.DTLVardef@bb7071org.highwire.dtl.DTLVardef@1d31a7aorg.highwire.dtl.DTLVardef@6f51f5_HPS_FORMAT_FIGEXP M_FIG C_FIG The graphic illustration of PDA-mediated photoprotection strategies to mimic natural melanin in RPE cells against blue light-induced phototoxicity in an Nrf2-deficient mouse model via a single-dose intravitreal (IVT) administration.

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Kwon, Y.-S., Zheng, M., Smirnov, A. I., Han, Z.. 2024-01-16. Polydopamine Nanoparticles as Mimicking RPE Melanin for the Protection of Retinal Cells Against Blue Light-Induced Phototoxicity. https://doi.org/10.1101/2024.01.15.575719

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