Department of Animal Biosciences, University of Guelph, Guelph, Canada.
Department of Biology, McMaster University, Hamilton, Canada.
Int J Radiat Biol. 2022;98(6):1130-1138. doi: 10.1080/09553002.2021.1980627. Epub 2021 Sep 28.
This investigation forms part of a wider study into the legacy effects of exposure of rainbow trout eggs 38 h after fertilization, eyed eggs, yolk sac larvae (YSL) or first feeders to a single 0.5 Gy X-ray dose, including the induction of a bystander effect, by the irradiated fish, to non-irradiated fish. Fish may be exposed to multiple environmental stressors, including waterborne metals, during their lifespan and, while there are data on how the legacy of early life stage irradiation and bystander effect induction is affected by waterborne aluminum and cadmium, there are no studies into the effects radiation or the radiation induced bystander effect on metal uptake. Therefore the aim of this investigation was to determine if the legacy of early life stage irradiation included an effect on copper uptake by adult fish and by non-irradiated bystander adult trout which swam with the irradiated fish.
The four early life stages mentioned above were exposed to a single 0.5 Gy X-ray dose and then maintained, for two years with no further irradiation. At two years old the irradiated fish were allowed to swim, for 2 h with non-irradiated bystander trout (also two years old). After this time copper uptake was determined using Cu.
Copper uptake was increased in adult trout irradiated as eggs at 48 h after fertilization and as first feeders but eyed egg or YSL irradiation had no effect. Copper uptake was also increased in the bystander trout which swam with trout irradiated as eggs at 48 h after fertilization and as eyed eggs but there was no effect on non-irradiated adult trout which swam with trout irradiated as YSL or first feeders.
When put in context with the proteomic changes observed in these fish we propose the increased copper uptake in adult trout irradiated as eggs at 48 h after fertilization could be part of an anti-tumorigenic response and the increase in copper uptake in adult trout irradiated as first feeders could be part of a potentially protective pro-apoptotic response. Similarly we propose the increase in copper uptake in non-irradiated adult trout, induced by trout irradiated as eggs at 48 h after fertilization or as eyed eggs, was part of the universally anti-tumorigenic nature of the X-ray induced bystander effect in fish. However this was exclusive to embryonic irradiation.
本研究是对受精后 38 小时的虹鳟鱼卵、眼斑期鱼卵、卵黄囊仔鱼（YSL）或初孵仔鱼单次接受 0.5GyX 射线照射后，通过受照射鱼对非受照射鱼产生的旁观者效应的后续影响的更广泛研究的一部分。鱼类在其一生中可能会暴露于多种环境胁迫因素下，包括水传播金属，尽管有关于早期阶段照射的遗传效应和旁观者效应诱导如何受到水传播铝和镉影响的数据，但尚无研究涉及辐射或辐射诱导的旁观者效应对金属摄取的影响。因此，本研究的目的是确定早期阶段照射的遗传效应对成年鱼类和与受照射鱼类一起游泳的非受照射旁观者成年鳟鱼的铜摄取是否有影响。
上述四个早期生命阶段均接受单次 0.5GyX 射线照射，然后维持两年不再进行照射。在两岁时，允许受照射的鱼与非受照射的旁观者鳟鱼（也为两岁）一起游泳 2 小时。此后，使用 Cu 确定铜摄取量。
受精后 48 小时照射的卵和初孵仔鱼的成年鳟鱼的铜摄取量增加，但眼斑期鱼卵或 YSL 照射没有影响。与受精后 48 小时照射的卵和眼斑期鱼卵照射的鳟鱼一起游泳的旁观者鳟鱼的铜摄取量也增加，但与 YSL 或初孵仔鱼照射的鳟鱼一起游泳的非受照射成年鳟鱼的铜摄取量没有增加。
将这些鱼中观察到的蛋白质组变化放在上下文中考虑，我们提出受精后 48 小时照射的卵中成年鳟鱼的铜摄取增加可能是抗肿瘤反应的一部分，而初孵仔鱼照射的成年鳟鱼的铜摄取增加可能是潜在的保护性促凋亡反应的一部分。同样，我们提出，受精后 48 小时照射的卵或眼斑期鱼卵照射的鳟鱼诱导的非受照射成年鳟鱼的铜摄取增加，是鱼类中 X 射线诱导的旁观者效应普遍具有抗肿瘤作用的一部分。然而，这仅适用于胚胎照射。
