Effects of heavy oil on occurrence of infectious disease and nervous development anomaly

本研究探讨了重油对鱼类感染性疾病和神经发育异常发生的影响。从一次实验感染的结果中，我们发现重油暴露导致携带病毒出血性败血症病毒(VHSV)的比目鱼高死亡率。与VHSV感染组相比，病毒+重油双重感染组的干扰素、细胞凋亡诱导等抗病毒活性相关基因的表达相对较低。因此，受双重应激源影响的鱼类体内的抗病毒活性受到抑制，这可能导致病毒在宿主细胞中的广泛复制，从而导致该病的发生。另一方面，我们观察到从重油暴露的胚胎中孵化出来的鱼的神经发育异常。从Sema3A探针的原位杂交实验结果来看，基因表达谱的改变是导致该异常的原因。

In this study, the effects of heavy oil on occurrence of fish infectious disease and nervous development anomaly were investigated. From the result of an experimental infection, we found that heavy oil exposure induced high mortality in viral hemorrhagic septicemia virus (VHSV)-carrier Japanese flounder Paralichthys olivaceus. The expressions of antiviral activity related genes such as interferon and apoptosis induction were relatively lower in the dual group (virus + heavy oil) compared with those of VHSV infection group. Thus, the antiviral activities were suppressed in the fish affected by the dual stressor, which might lead to extensive viral replication in the host cells, resulting in the occurrence of the disease. On the other hand, we observed nervous developmental anomaly in the fish hatched from heavy oil-exposed embryo. From the result of in situ hybridization experiment using sema3A probe, it is suggested that changes of the gene expression profile was responsible for the anomaly.