Data Sheet 1_Photodynamic therapy with a novel photosensitizer inhibits DSS-induced ulcerative colitis in rats via the NF-κB signaling pathway.docx

IntroductionUlcerative colitis (UC) is an inflammatory bowel disease characterized by inflammation and ulceration of the digestive tract.
MethodsPhotodynamic therapy (PDT) with a novel photosensitizer LD4 was used to treat UC rat models to explore the therapeutic effect and mechanism of LD4-PDT on UC. 16S ribosomal RNA was used to detect the composition of Gut microbiota.
ResultsOur findings indicate that LD4-PDT could protect the integrity of the colonic mucosa, alleviate the inflammatory response and promote the healing of colonic mucosa. Mechanism studies demonstrated that LD4-PDT could inhibit the NF-κB signaling pathway, downregulated the expression of the inflammatory factors’ tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and myeloperoxidase (MPO), increased the contents of glutathione (GSH) and superoxide dismutase (SOD) and decreased the content of malondialdehyde (MDA). Additionally, analysis of gut microbiota revealed that LD4-PDT treatment could decrease the abundance of the Proteobacteria phylum in fecal samples, while no significant differences were observed in the Firmicutes, Bacteroidetes, or Actinobacteria phyla among the three groups using 16S rRNA analysis.
DiscussionIn summary, our data suggested that LD4-PDT could inhibit DSS-induced UC in rats via the NF-κB signaling pathway, indicating its potential as a novel photosensitizer for the treatment of UC.

引言：溃疡性结肠炎（Ulcerative colitis, UC）是一种以消化道炎症与溃疡为特征的炎症性肠病。
方法：采用新型光敏剂LD4介导的光动力疗法（Photodynamic therapy, PDT）治疗溃疡性结肠炎大鼠模型，探讨LD4-PDT对溃疡性结肠炎的治疗效果及作用机制。采用16S核糖体RNA（16S ribosomal RNA）检测肠道菌群组成。
结果：本研究结果表明，LD4-PDT可保护结肠黏膜完整性，减轻炎症反应并促进结肠黏膜愈合。机制研究证实，LD4-PDT可抑制核因子-κB（NF-κB）信号通路，下调炎症因子肿瘤坏死因子-α（tumor necrosis factor-α, TNF-α）、白细胞介素-6（interleukin-6, IL-6）及髓过氧化物酶（myeloperoxidase, MPO）的表达，升高谷胱甘肽（glutathione, GSH）与超氧化物歧化酶（superoxide dismutase, SOD）的含量，降低丙二醛（malondialdehyde, MDA）的含量。此外，肠道菌群分析显示，LD4-PDT治疗可降低粪便样本中变形菌门（Proteobacteria phylum）的丰度；16S rRNA分析表明，三组大鼠的厚壁菌门（Firmicutes）、拟杆菌门（Bacteroidetes）及放线菌门（Actinobacteria）的丰度无显著差异。
讨论：综上，本研究数据提示，LD4-PDT可通过抑制核因子-κB信号通路减轻葡聚糖硫酸钠（Dextran sulfate sodium, DSS）诱导的大鼠溃疡性结肠炎，表明其作为新型光敏剂用于溃疡性结肠炎治疗的应用潜力。