PDF(Pubmed)
Abstract：
BACKGROUND: Spring viremia of carp virus (SVCV) infects a wide range of fish species and causes high mortality rates in aquaculture. This viral infection is characterized by seasonal outbreaks that are temperature-dependent. However, the specific mechanism behind temperature-dependent SVCV infectivity and pathogenicity remains unclear. Given the high sensitivity of the composition of intestinal microbiota to temperature changes, it would be interesting to investigate if the intestinal microbiota of fish could play a role in modulating the infectivity of SVCV at different temperatures.
RESULTS: Our study found that significantly higher infectivity and pathogenicity of SVCV infection in zebrafish occurred at relatively lower temperature. Comparative analysis of the intestinal microbiota in zebrafish exposed to high- and low-temperature conditions revealed that temperature influenced the abundance and diversity of the intestinal microbiota in zebrafish. A significantly higher abundance of Parabacteroides distasonis and its metabolite secondary bile acid (deoxycholic acid, DCA) was detected in the intestine of zebrafish exposed to high temperature. Both colonization of Parabacteroides distasonis and feeding of DCA to zebrafish at low temperature significantly reduced the mortality caused by SVCV. An in vitro assay demonstrated that DCA could inhibit the assembly and release of SVCV. Notably, DCA also showed an inhibitory effect on the infectious hematopoietic necrosis virus, another Rhabdoviridae member known to be more infectious at low temperature.
CONCLUSIONS: This study provides evidence that temperature can be an important factor to influence the composition of intestinal microbiota in zebrafish, consequently impacting the infectivity and pathogenicity of SVCV. The findings highlight the enrichment of Parabacteroides distasonis and its derivative, DCA, in the intestines of zebrafish raised at high temperature, and they possess an important role in preventing the infection of SVCV and other Rhabdoviridae members in host fish. Video Abstract.
RESULTS: Our study found that significantly higher infectivity and pathogenicity of SVCV infection in zebrafish occurred at relatively lower temperature. Comparative analysis of the intestinal microbiota in zebrafish exposed to high- and low-temperature conditions revealed that temperature influenced the abundance and diversity of the intestinal microbiota in zebrafish. A significantly higher abundance of Parabacteroides distasonis and its metabolite secondary bile acid (deoxycholic acid, DCA) was detected in the intestine of zebrafish exposed to high temperature. Both colonization of Parabacteroides distasonis and feeding of DCA to zebrafish at low temperature significantly reduced the mortality caused by SVCV. An in vitro assay demonstrated that DCA could inhibit the assembly and release of SVCV. Notably, DCA also showed an inhibitory effect on the infectious hematopoietic necrosis virus, another Rhabdoviridae member known to be more infectious at low temperature.
CONCLUSIONS: This study provides evidence that temperature can be an important factor to influence the composition of intestinal microbiota in zebrafish, consequently impacting the infectivity and pathogenicity of SVCV. The findings highlight the enrichment of Parabacteroides distasonis and its derivative, DCA, in the intestines of zebrafish raised at high temperature, and they possess an important role in preventing the infection of SVCV and other Rhabdoviridae members in host fish. Video Abstract.
摘要：
背景：鲤鱼病毒春季病毒血症（SVCV）感染多种鱼类，并在水产养殖中导致高死亡率。这种病毒感染的特征是温度依赖性的季节性爆发。然而,温度依赖性SVCV感染性和致病性背后的具体机制尚不清楚.鉴于肠道微生物群的组成对温度变化的高度敏感性，研究鱼的肠道菌群是否可以在不同温度下调节SVCV的感染性中发挥作用。
结果：我们的研究发现，斑马鱼中SVCV感染的感染性和致病性明显更高，发生在相对较低的温度下。对暴露于高温和低温条件下的斑马鱼肠道菌群的比较分析表明，温度影响斑马鱼肠道菌群的丰度和多样性。一种明显较高丰度的副杆菌属双杆菌属及其代谢产物次生胆汁酸(脱氧胆酸，在暴露于高温的斑马鱼的肠道中检测到DCA）。在低温下对斑马鱼进行DCA的定植和对斑马鱼的摄食均显着降低了SVCV引起的死亡率。体外实验表明，DCA可以抑制SVCV的组装和释放。值得注意的是,DCA对传染性造血系统坏死病毒也有抑制作用,另一个已知在低温下更具传染性的弹状病毒科成员。
结论：这项研究提供了证据，表明温度可能是影响斑马鱼肠道菌群组成的重要因素，从而影响SVCV的感染性和致病性。研究结果突出了双杆菌属及其衍生物的富集，DCA,在高温下生长的斑马鱼的肠道中，它们在预防宿主鱼类中SVCV和其他弹状病毒科成员的感染中具有重要作用。视频摘要。
结果：我们的研究发现，斑马鱼中SVCV感染的感染性和致病性明显更高，发生在相对较低的温度下。对暴露于高温和低温条件下的斑马鱼肠道菌群的比较分析表明，温度影响斑马鱼肠道菌群的丰度和多样性。一种明显较高丰度的副杆菌属双杆菌属及其代谢产物次生胆汁酸(脱氧胆酸，在暴露于高温的斑马鱼的肠道中检测到DCA）。在低温下对斑马鱼进行DCA的定植和对斑马鱼的摄食均显着降低了SVCV引起的死亡率。体外实验表明，DCA可以抑制SVCV的组装和释放。值得注意的是,DCA对传染性造血系统坏死病毒也有抑制作用,另一个已知在低温下更具传染性的弹状病毒科成员。
结论：这项研究提供了证据，表明温度可能是影响斑马鱼肠道菌群组成的重要因素，从而影响SVCV的感染性和致病性。研究结果突出了双杆菌属及其衍生物的富集，DCA,在高温下生长的斑马鱼的肠道中，它们在预防宿主鱼类中SVCV和其他弹状病毒科成员的感染中具有重要作用。视频摘要。
