X-Irradiation at 0.5 Gy after the forced swim test reduces forced swimming-induced immobility in mice

The forced swim test (FST) is a screening model for antidepressant activity; it causes immobility and induces oxidative stress. We previously reported that radon inhalation has antidepressant-like effects in mice potentially through the activation of antioxidative functions upon radon inhalation. This study aimed to investigate the effect of prior and post low-dose X-irradiation (0.1, 0.5, 1.0 and 2.0 Gy) on FST-induced immobility and oxidative stress in the mouse brain, and the differences, if any, between the two. Mice received X-irradiation before or after the FST repeatedly for 5 days. In the post-FST-irradiated group, an additional FST was conducted 4h after the last irradiation. Consequently, animals receiving prior X-irradiation (0.1 Gy) had better mobility outcomes than sham-irradiated mice; however, their levels of lipid peroxide (LPO), an oxidative stress marker, remained unchanged. However, animals that received post-FST X-irradiation (0.5 Gy) had better mobility outcomes and their LPO levels were significantly lower than those of the sham-irradiated mice. The present results indicate that 0.5 Gy X-irradiation after FST inhibits FST-induced immobility and oxidative stress in mice

Protective Effects of Radon Inhalation on Carrageenan-Induced Inflammatory Paw Edema in Mice

We assessed whether radon inhalation inhibited carrageenan-induced inflammation in mice. Carrageenan (1% v/v) was injected subcutaneously into paws of mice that had or had not inhaled approximately 2,000 Bq/m3 of radon for 24 h. Radon inhalation significantly increased superoxide dismutase (SOD) and catalase activities and significantly decreased lipid peroxide levels in mouse paws, indicating that radon inhalation activates antioxidative functions. Carrageenan administration induced paw edema and significantly increased tumor necrosis factor-alpha (TNF-α) and nitric oxide in serum. However, radon inhalation significantly reduced carrageenan-induced paw edema. Serum TNF-α levels were lower in the radon-treated mice than in sham-treated mice. In addition, SOD and catalase activities in paws were significantly higher in the radon-treated mice than in the sham-treated mice. These findings indicated that radon inhalation had anti-inflammatory effects and inhibited carrageenan-induced inflammatory paw edema

Comparative Study on the Inhibitory Effects of α-Tocopherol and Radon on Carbon Tetrachloride-Induced Renal Damage

Since the 2011 nuclear accident in Fukushima, the effects of low-dose irradiation, especially internal exposure, are at the forefront of everyone’s attention. However, low-dose radiation induced various stimulating effects such as activation of antioxidative and immune functions. In this study, we attempted to evaluate the quantitative effects of the activation of antioxidative activities in kidney induced by radon inhalation on carbon tetrachloride (CCl4)-induced renal damage. Mice were subjected to intraperitoneal (i.p.) injection of CCl4 after inhaling approximately 1000 or 2000 Bq/m3 radon for 24 h, or immediately after i.p. injection of α-tocopherol (100, 300, or 500 mg/kg bodyweight). In case of renal function, radon inhalation at a concentration of 2000 Bq/m3 has the inhibitory effects similar to α-tocopherol treatment at a dose of 300–500 mg/kg bodyweight. The activities of superoxide dismutase and catalase in kidneys were significantly higher in mice exposed to radon as compared to mice treated with CCl4 alone. These findings suggest that radon inhalation has an antioxidative effect against CCl4-induced renal damage similar to the antioxidative effects of α-tocopherol due to induction of antioxidative functions

The CD45+ fraction in murine adipose tissue derived stromal cells harbors immune-inhibitory inflammatory cells

金沢大学医薬保健研究域医学系Stromal cells in adipose tissue are useful for repair/regenerative therapy as they harbor a substantial number of mesenchymal stem cells; therefore, freshly isolated autologous uncultured adipose tissue derived stromal cells (u-ADSCs) are useful for regenerative therapy, and obviate the need for mesenchymal stem cells. We evaluated the therapeutic effect of murine u-ADSCs and sorted subsets of u-ADSCs in a concanavalin A (ConA) induced murine model of hepatitis, as well as their characteristics. We found that 10–20% of u-ADSCs expressed the CD45 leukocyte-related antigen. CD68, which is a marker of macrophages (MΦs), was expressed by 50% of CD45+ u-ADSCs. About 90% of CD68+CD45+ cells expressed CD206 antigen, which is a marker of inhibitory M2-type MΦs. Genes related to M2-type MUs were especially more highly expressed by CD45+CD206+ u-ADSCs than by CD45− u-ADSCs. CD45+ u-ADSCs inhibited the expression of cytokines/chemokines and suppressed the proliferation of splenocytes stimulated with ConA. We observed that not only whole u-ADSCs, but also the CD45+ subset of u-ADSCs ameliorated the ConA-induced hepatitis in mice. In conclusion, we show that freshly isolated murine u-ADSCs were effective against acute hepatitis, and CD45+ u-ADSCs acting phenotypically and functionally like M2-type MΦs, contributed to the repair of liver tissue undergoing inflammation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimEmbargo Period 12 month

Suppression of Dextran Sulfate Sodium-Induced Colitis in Mice by Radon Inhalation

The enhanced release of reactive oxygen species from activated neutrophils plays important role in the pathogenesis of inflammatory bowel disease. We previously reported that radon inhalation activates antioxidative functions in various organs of mice. In this study, we examined the protective effects of radon inhalation on dextran sulfate sodium- (DSS) induced colitis in mice which were subjected to DSS for 7 days. Mice were continuously treated with air only (sham) or radon at a concentration of 2000 Bq/m3 from a day before DSS administration to the end of colitis induction. In the results, radon inhalation suppressed the elevation of the disease activity index score and histological damage score induced by DSS. Based on the changes in tumor necrosis factor-alpha in plasma and myeloperoxidase activity in the colon, it was shown that radon inhalation suppressed DSS-induced colonic inflammation. Moreover, radon inhalation suppressed lipid peroxidation of the colon induced by DSS. The antioxidant level (superoxide dismutase and total glutathione) in the colon after DSS administration was significantly higher in mice treated with radon than with the sham. These results suggested that radon inhalation suppressed DSS-induced colitis through the enhancement of antioxidative functions in the colon