The influences of purple sweet potato anthocyanin on the growth characteristics of human retinal pigment epithelial cells

Abstract

BackgroundAnthocyanins have been proven to be beneficial to the eyes. However, information is scarce about the effects of purple sweet potato (Ipomoea batatas, L.) anthocyanin (PSPA), a class of anthocyanins derived from purple sweet potato roots, on visual health.ObjectiveThe aim of this study was to investigate whether PSPA could have influences on the growth characteristics (cellular morphology, survival, and proliferation) of human retinal pigment epithelial (RPE) cells, which perform essential functions for the visual process.MethodsThe RPE cell line D407 was used in the present study. The cytotoxicity of PSPA was assessed by MTT assay. Then, cellular morphology, viability, cell cycle, Ki67expression, and PI3K/MAPK activation of RPE cells treated with PSPA were determined.ResultsPSPA exhibited dose-dependent promotion of RPE cell proliferation at concentrations ranging from 10 to 1,000 µg/ml. RPE cells treated with PSPA demonstrated a predominantly polygonal morphology in a mosaic arrangement, and colony-like cells displayed numerous short apical microvilli and typical ultrastructure. PSPA treatment also resulted in a better platform growing status, statistically higher viability, an increase in the S-phase, and more Ki67+ cells. However, neither pAkt nor pERK were detected in either group.ConclusionsWe found that PSPA maintained high cell viability, boosted DNA synthesis, and preserved a high percentage of continuously cycling cells to promote cell survival and division without changing cell morphology. This paper lays the foundation for further research about the damage-protective activities of PSPA on RPE cells or human vision.

Cyanidin‐3‐glucoside and its phenolic acid metabolites attenuate visible light‐induced retinal degeneration in vivo via activation of Nrf2/HO‐1 pathway and NF‐κB suppression

“…The most abundant ACN in the edible parts of plants is cyanidin‐3‐glucoside (C3G) . C3G facilitates rhodopsin regeneration in rod photoreceptors, interacts directly with the dark and light forms of rhodopsin and opsin protein, and inhibits the photooxidation of retinal pigment epithelial (RPE) cells . In addition, C3G can be detected in the eyes by oral administration of blueberry, thereby suggesting its possible role in protecting against retinal diseases .…”

‘Alisha’, ‘Anamaria’, ‘Bie’, ‘Bita’, ‘Caelan’, ‘Ivone’, ‘Lawrence’, ‘Margarete’, and ‘Victoria’ Sweetpotato

“…However, food and fodder dual-purpose cultivars were not available in African sweetpotato germplasm (Niyireba et al, 2013) until the recent release of RW cultivars by the Rwanda Agriculture Board and the International Potato Center (CIP) (Shumbusha et al, 2014). Purplefleshed sweetpotatoes (PFSP) are the sources of antioxidants (Teow et al, 2007), and anthocyanins derived from PFSP affect the growth of human retinal pigment damageprotective activities on epithelial cells (Kubow et al, 2016;Sun et al, 2015). Moreover, PFSP can be used for natural food coloring, which is a relatively new market for sweetpotato and cultivars high in anthocyanin, are increasingly becoming popular in Asia used fresh or in a variety of processed snacks (Gilbert, 2005;Timberlake and Henry, 1988).…”

Purple sweet potato anthocyanin exerts antitumor effect in bladder cancer

“…By contrast, PSPA exhibited an opposite effect in non-cancerous cells by enhancing cell viability and resistance to apoptosis. Furthermore, according to previous studies, PSPA was capable of inhibiting the proliferation in multiple cell types ( 24 ), while the proliferation and anti-apoptotic effect of PSPA has also been reported ( 25 , 26 ). The reason for this appeared contradictory effect was not very clear.…”

“…This was in agreement with some cancer cell studies ( 13 , 14 ). There were studies that reported a promotion effect of PSPA on cell viability ( 25 , 33 ). The anthocyanins appeared to have a paradoxical role in the generation of the ROS ( 34 – 36 ).…”