Many alterations to the skin microbiome by exposure to UV radiation (UVR) have been postulated and may contribute to the ability of UVR phototherapy to regulate skin inflammatory diseases. Very recently, an effect of sub-erythemal narrowband UVB radiation (311 nm) on the gut microbiome of healthy individuals was reported. The relative abundance of Firmicutes and Proteobacteria increased in faecal samples of those receiving three exposures to narrowband UVB radiation; the Bacteroidetes phyla were reduced by UVB. In mice chronically exposed to sub-erythemal broadband UVR, similar faecal changes in Firmicutes and Bacteroidetes have been reported. Murine studies have allowed a further dissection of the relative ability of UVR and dietary vitamin D to modulate the gut microbiome by analysis of relative bacterial abundance in mice with similar 25-hydroxy vitamin D levels obtained by UVR exposure or from their diet, respectively. The studies of mice recovering from colitis suggested that dietary vitamin D could stimulate greater faecal abundance of Rikenellaceae, whilst exposure to UVR was necessary for changes to the abundance of Lachnospiraceae and Desulfovibrionaceae. Both human and murine studies report that multiple exposures to sub-erythemal UVR can increase the diversity of the gut microbiome, which in turn may be beneficial to the health of the host.

中文翻译：

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UVR暴露对小鼠和人类肠道菌群的影响。

已经假定通过暴露于紫外线辐射（UVR）对皮肤微生物组有许多改变，这些改变可能有助于UVR光疗调节皮肤炎症性疾病的能力。最近，有报道称红斑窄带UVB辐射（311 nm）对健康个体的肠道微生物组有影响。粪便样品中窄带UVB辐射3次暴露后，菌丝体和变形杆菌的相对丰度增加。UVB减少了拟杆菌门。在长期暴露于红斑下宽带UVR的小鼠中，已经报道了Firmicutes和Bacteroidetes中类似的粪便变化。鼠类研究通过分析分别通过紫外线照射或饮食获得的具有类似25-羟基维生素D水平的小鼠中的相对细菌丰度，可以进一步剖析UVR和膳食维生素D调节肠道微生物组的相对能力。对从结肠炎中恢复的小鼠的研究表明，饮食中的维生素D可以刺激蓖麻科的粪便丰度，而暴露于UVR是改变漆螺科和脱硫弧菌科的丰度所必需的。人类和鼠类研究均报告，多次暴露于红斑下的紫外线辐射可增加肠道微生物组的多样性，这反过来可能有益于宿主的健康。从结肠炎中恢复过来的小鼠的研究表明，饮食中的维生素D可以刺激大肠科的粪便丰度，而暴露于UVR是改变漆螺科和脱硫弧菌科的丰度所必需的。人类和鼠类研究均报告，多次暴露于红斑下的紫外线辐射可增加肠道微生物组的多样性，这反过来可能有益于宿主的健康。从结肠炎中恢复过来的小鼠的研究表明，饮食中的维生素D可以刺激大肠科的粪便丰度，而暴露于UVR是改变漆螺科和脱硫弧菌科的丰度所必需的。人类和鼠类研究均报告，多次暴露于红斑下的紫外线辐射可增加肠道微生物组的多样性，这反过来可能有益于宿主的健康。