Evaluation of the redox state in mouse organs following radon inhalation

片岡 隆浩*; 神崎 訓枝; 迫田 晃弘; 首藤 妃奈*; 矢野 準喜*; 直江 翔太*; 田中 裕史; 花元 克巳*; 寺東 宏明*; 光延 文裕*; et al.

Journal of Radiation Research (Internet), 62(2), p.206 - 216, 2021/03

AA2020-0273.pdf:1.2MB

https://doi.org/10.1093/jrr/rraa129

ラドン吸入はマウス臓器の抗酸化機能を活性化させ、酸化ストレスに誘導されたダメージを抑制する。そこで、本研究では、ラドン吸入後の臓器中のレドックス状態を評価した。2, 20kBq/mのラドンを1, 3, 10日間マウスに吸入させ、主成分分析や相関の変化から、抗酸化機能と酸化ストレスの関係を評価した。本研究の結果は、臓器特有のレドックス状態に依存してラドン吸入後の臓器のレドックス状態が変化したことを示唆した。

Oxidative stress suppresses locomotion and pumping motion in

鈴木 芳代; 坂下 哲哉; 服部 佑哉; 小林 泰彦

no journal, , 

We recently found that whole body irradiation reduced locomotion in , though the mechanisms are not clear. It is well known that free radicals such as OH and H are produced following exposure of ionizing radiation. The reactions of free radicals cause the production of oxidative stress including hydrogen peroxide (HO). Oxidative stress is known as an important factor of aging, and may relate to the decrease of motility observed in the aging process. We therefore explored the potential effectiveness of HO in the suppression of 's locomotion. Wild-type animals were exposed to graded doses of HO and the locomotory rate was evaluated. The locomotory rate was significantly decreased in HO-exposed animals, in which the dose response was similar to that in the irradiated animals. We subsequently investigated the radiation effects on the pharyngeal pumping motion (chewing and swallowing) and the involvement of oxidative stress. As a result, the proportion of the pumping-motion arrest significantly increased after whole body irradiation and the pumping-motion arrest was restored within several hours. Furthermore, the response in HO-exposed animals was similar to that in the irradiated animals. These results support the possibility that radiation-induced suppression of both locomotion and pumping motion in was caused by radiation-produced HO.

Detection and measurement of abnormal posture under stressful conditions in age-related mutants

Matsuda, Sakiyo*; Nitta, Nazuki*; Tamura, Miku*; 鈴木 芳代; 坂下 哲哉; 石井 直明*; 簗瀬 澄乃*

no journal, , 

Oxidative stress threatens cellular constructs including lipids, proteins and nucleic acids. As a result, oxidative stress causes or influence apoptosis, degenerative diseases and aging. Recently, we found an abnormal posture in short-lived mutants such as and , exposed to hyperoxia. In this study, we detected the hyperoxia-induced abnormal posture in and mutants compared with wild-type N and long-lived strains. 4-day-old animals placed on a NGM agar plate with a fixed bacterial lawn were exposed to hyperoxia (90% of oxygen) overnight. After the exposure, some animals were immediately recorded as digital images with up to 400-fold magnification of the microscope. The images were analyzed using image-processing software by a previously published method. To evaluate the posture of the body, we introduced a novel standard, namely the "posture index" as the absolute average of the relative angle between adjacent dividing points. As a result of this investigation, we can not only intuitively but also quantitatively and statistically understand a tendency of the behavior in various postural responses under stressful conditions in the short-lived mutants.

マウスの脳および肝臓中のラドン吸入による硫黄関連代謝物の変化

神崎 訓枝; 迫田 晃弘; 片岡 隆浩*; 田中 裕史; 山岡 聖典*

no journal, , 

近年、チオール(SH)基に過剰な硫黄原子が付加した活性イオウ分子種(RSS)は、強い抗酸化能とレドックスシグナル制御能を有していることが報告されている。そこで、本研究では、ラドン吸入とRSSの関連を検討することを目的とし、マウスの脳と肝臓でメタボローム解析を行った。ラドン吸入によって、脳では、メチオニンの増加,尿素,グルタチオン(G-SH),亜硫酸イオンの減少などが見られた。肝臓では、酸化型グルタチオン(GS-SG)の減少傾向などが見られた。また、脳や肝臓中のG-SH等のRSS(例えば、G-S-SH)の割合が増加した。今後は、脳・肝臓以外の臓器についても検討し、RSSがラドン吸入による酸化ストレス関連疾患の抑制に関与する可能性を明らかにしたい。