Protective effect of inhalation of hydrogen gas on radiation-induced dermatitis and skin injury in rats

Abstract

The effect of inhalation of hydrogen-containing gas (1.3% hydrogen + 20.8% oxygen + 77.9% nitrogen) (HCG) on radiation-induced dermatitis and on the healing of healing-impaired skin wounds in rats was examined using a rat model of radiation-induced skin injury. An X-ray dose of 20 Gy was irradiated onto the lower part of the back through two holes in a lead shield. Irradiation was performed before or after inhalation of HCG for 2 h. Inhalation of HCG significantly reduced the severity of radiodermatitis and accelerated healing-impaired wound repair. Staining with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) showed that the proportion of apoptotic keratinocytes and the level of staining in the X-irradiated skin of rats that pre-inhaled HCG were significantly lower than that of rats which did not pre-inhale HCG. Cutaneous full-thickness wounds were then created in the X-irradiated area to examine the time-course of wound healing. X-irradiation significantly increased the time required for wound healing, but the inhalation of HCG prior to the irradiation significantly decreased the delay in wound healing compared with the control and post-inhalation of HCG groups. Therefore, radiation-induced skin injury can potentially be alleviated by the pre-inhalation of HCG.

Cytotoxicity of Silver Nanoparticle and Chitin-Nanofiber Sheet Composites Caused by Oxidative Stress

“…The result also indicated mitigation of the delay in wound repair with Ag NPs/CNFS with saline wash. For histological observation, 8-hydroxy-2′-deoxyguanosine (8-OHdG) immunohistochemical staining of skin sections after 24 h was performed to measure the 8-OHdG-positive sites (Figure 5). The 8-OHdG indicates the hyperoxidation state of nucleic acids, allowing evaluation of the antioxidative effect [30]. Significant increases in the number of 8-OHdG-positive sites were observed in the Ag NPs/CNFS-treated wounds compared with the CNFS-treated (control) wounds (Figure 5).…”

“…Protein oxidation, which produces carbonyl proteins, is defined as the covalent modification of proteins induced either directly by reactive oxygen species (ROS) or indirectly by reaction with secondary byproducts of oxidative stress [30,31]. Figure 6 shows a scheme of carbonyl protein assay.…”

“…The increase of total NO/NO 2 levels treated with either Ag NPs/CNFS or Ag NPs might indicate enhanced inflammation as a source of oxidative stress, since NO acts a second messenger in inflammatory signaling and is immediately changed to NO 2 [32]. The 8-OHdG staining indicates the hyperoxidation state of nucleic acids, allowing the antioxidative effect to be evaluated [30]. The use of carbonyl protein as a biomarker of oxidative stress has some advantages compared to the measurement of other oxidation products, such as the relatively early formation and stability of carbonylated proteins [31].…”

Evaluation of edaravone against radiation-induced oral mucositis in mice

“…ROS such as the oxygen radical (O 2 À ) and hydrogen peroxide (H 2 O 2 ) are detoxified easily by antioxidant defense enzymes, whereas cytotoxic ROS, such as the hydroxyl radical ( OH), cannot be detoxified by these enzymes. During radiotherapy, the detrimental effects of ionizing radiation on biological tissues such as the skin are mediated primarily by cytotoxic ROS such as OH, which induces excess apoptosis (8).…”

Hydrogen Medicine Therapy: An Effective and Promising Novel Treatment for Multiple Organ Dysfunction Syndrome (MODS) Induced by Influenza and Other Viral Infections Diseases?

“…It's interesting to note that H2 therapy can be administered through inhalation, oral intake of hydrogen-rich water, injection of hydrogen-rich saline, direct diffusion of hydrogen: bath, eye drops and immersion, as well as increase hydrogen in intestine [11,[61][62][63][64][65][66][67][68][69]. Although each delivery way has its own characteristic and advantages, injection of hydrogen-rich saline allows enough amount of hydrogen to have its own antioxidant, anti-inflammation, anti-apoptosis effect at the shortest time [11,70].…”