*Article* **Antioxidative E** ff**ects of Ascorbic Acid and Astaxanthin on ARPE-19 Cells in an Oxidative Stress Model**

#### **Sanghyeon Oh 1,**†**, Young Joo Kim 2,**†**, Eun Kyoung Lee 3,**†**, Sung Wook Park 3 and Hyeong Gon Yu 3,\***


Received: 31 July 2020; Accepted: 3 September 2020; Published: 6 September 2020

**Abstract:** Oxidative stress has been implicated as critical pathogenic factors contributing to the etiology of diabetic retinopathy and other retinal diseases. This study investigated antioxidative effect of ascorbic acid and astaxanthin on ARPE-19 cells within an oxidative stress model induced by common biological sources of reactive oxygen species (ROS). Hydrogen peroxide (H2O2) at concentrations of 0.1–0.8 mM and 20–100 mJ/cm<sup>2</sup> of ultraviolet B (UVB) were treated to ARPE-19 cells. Cell viability and intracellular ROS level changes were measured. With the sublethal and lethal dose of each inducers, 0–750 μM of ascorbic acid and 0–40 μM of astaxanthin were treated to examine antioxidative e ffect on the model. Ascorbic acid at concentrations of 500 and 750 μM increased the cell viability not only in the UVB model but also in the H2O2 model, but 20 and 40 μM of astaxanthin only did so in the UVB model. The combination of ascorbic acid and astaxanthin showed better antioxidative e ffect compared to each drug alone, suggesting a synergistic e ffect.

**Keywords:** antioxidant; ascorbic acid; astaxanthin; oxidative stress; diabetic retinopathy; retinal pigment epithelium; retinal disease
