Ascorbic Acid 2-Glucoside Pretreatment Protects Cells from Ionizing Radiation, UVC, and Short Wavelength of UVB

Abstract

Ascorbic acid 2-glucoside (AA2G), glucosylated ascorbic acid (AA), has superior properties for bioavailability and stability compared to AA. Although AA2G has shown radioprotective properties similar to AA, effects for UV light, especially UVC and UVB, are not studied. AA2G was tested for cytotoxicity and protective effects against ionizing radiation, UVC, and broadband and narrowband UVB in Chinese hamster ovary (CHO) cells and compared to AA and dimethyl sulfoxide (DMSO). Pretreatment with DMSO, AA, and AA2G showed comparative protective effects in CHO wild type and radiosensitive xrs5 cells for cell death against ionizing radiation with reducing the number of radiation-induced DNA damages. Pretreatment with AA and AA2G protected CHO wild type and UV sensitive UV135 cells from UVC and broadband UV, but not from narrowband UVB. DMSO showed no protective effects against tested UV. The UV filtration effects of AA and AA2G were analyzed with a spectrometer and spectroradiometer. AA and AA2G blocked UVC and reduced short wavelengths of UVB, but had no effect on wavelengths above 300 nm. These results suggest that AA2G protects cells from radiation by acting as a radical scavenger to reduce initial DNA damage, as well as protecting cells from certain UVB wavelengths by filtration.

Two Faces of Vitamin C—Antioxidative and Pro-Oxidative Agent

“…Both pre-treatment and post-treatment AA-2G (2-glucopyranoside ascorbic acid) fibroblasts show radioresistance [111]. AA-2G is a stable form of ascorbic acid used to create cosmetics [112]. AA-2G pre-treated cells are more resistant to gamma radiation (6 Gy), and the effect of post-treatment was to reduce DNA damage (in this case DSBs).…”

Cytotoxicity and Mutagenicity of Narrowband UVB to Mammalian Cells

“…One of these studies showed that UVB light, in the range of 10–1000 J/m 2 , caused a marked increase in the formation of ROS in both human and mouse keratinocytes [ 42 ]. Additionally, previous research showed ROS scavengers can reduce the cytotoxicity of UVB [ 43 , 44 ]. Our results agree with these prior studies of ROS generated by UVB, as we observed that both BB-UVB and NB-UVB were capable of inducing ROS.…”

“…Our results demonstrated NB-UVB was far less efficient at formation of CPDs in comparison to unfiltered BB-UVB per absorbed dose (J/m 2 ) even when the cap was on during BB-UVB irradiation. In a prior study, Maeda et al demonstrated the filtration effect of the petri dish cap being on during BB-UVB exposure [ 43 ]. Thus, we suggest that this observation may have been the result of shorter wavelengths within the BB-UVB spectrum not being able to penetrate the petri dish cap, essentially filtering the BB-UVB, which may explain the linear trend resembling that of NB-UVB.…”

Evaluating the Genotoxic and Cytotoxic Effects of Thymidine Analogs, 5-Ethynyl-2′-Deoxyuridine and 5-Bromo-2′-Deoxyurdine to Mammalian Cells

“…Phillip’s germicidal UV-C lamps were used as a UV-C source with a fluence of 1 W/m 2 . Dosimetry was carried out using a UVP UVX dosimeter with a UV-C probe (UVP, Upland, CA, USA) [ 50 ]. Cell culture dishes were rotated at 6 rpm during UV-C exposure to ensure even exposure to all areas of the dish.…”