Anorectal Surgery of Zhongda Hospital Southeast University, Nanjing, 210009, China.
Graduate School of Nanjing University of Chinese Medicine, Nanjing, 210029, China.
Stem Cell Res Ther. 2022 Jun 21;13(1):272. doi: 10.1186/s13287-022-02940-x.
Inflammatory bowel diseases, consisting of Crohn's disease and ulcerative colitis constitute chronic inflammatory conditions that may compromise the whole gastrointestinal tract as well as the colonic mucosa. Currently, there are no curative interventions for IBD, and all available treatments have side effects that limit their use. Adipose-derived stem cell (ADSC) treatment is a prospective treatment option for IBD. Previous findings indicated that ginsenoside (Rg1) dampened inflammatory diseases like colitis by inhibiting the binding of LPS to TLR4 on macrophages and restoring the Th17/Treg ratio. The purpose of this work was to investigate whether Rg1 can increase the influence of ADSC in a mouse model of colitis triggered by dextran sulfate sodium (DSS).
ADSC was intravenously inoculated into mice with DSS-triggered colitis, while Rg1 was delivered via oral gavage. Colon inflammation was assessed via body weight, colon length along with H&E staining. Serum cytokine levels were measured using ELISA. Besides, flow cytometry was adopted to determine the percentage, as well as FMI of immune cells in the spleen. The effects of simultaneous Rg1 and ADSC treatment on TLR4-MyD88 signaling were assessed via immunofluorescence.
Rg1 and ADSC effectively alleviated the impacts of colon inflammation, weight loss, and colon length reduction along with histological score. Treatment with Rg1 and ADSC reduced serum levels of the proinflammatory cytokines, IL-1β, TNF-α, IL-6, IL-4, and IL-17A and upregulated the level of immunosuppressive cytokine, IL-10. Compared with ADSC or Rg1 alone, combined treatment with Rg1 and ADSC significantly improved the structure of microbial community. Additionally, treatment with Rg1 plus ADSC selectively elevated the level of splenic regulatory T (Treg) cells and downregulated the proportion of T helper type 17 (Th17) cells, indicating restoration of intestinal homeostasis. Besides, we established that the combination of ADSC + Rg1 restored immunological balance more effectively than either ADSC or Rg1 alone, illustrating that Rg1's modulatory function on the gut microbiota may boost the impact of ADSCs in restoration of the immune balance. ADSC combined with Rg1 might downregulate the expression of TLR4 and MyD88, thereby suppressing TLR4-MyD8 signaling. The immunofluorescence results also suggested that co-therapy with Rg-1 and ADSC may optimize treatment strategies of IBD.
Here, we find that the combination of Rg1 and ADSC alleviates DSS-induced colitis in a mouse model more efficiently than ADSC alone, indicating that Rg1 enhances the effect of ADSC against colitis.
炎症性肠病（IBD）包括克罗恩病和溃疡性结肠炎，是一种慢性炎症性疾病，可能会影响整个胃肠道以及结肠黏膜。目前，IBD 没有治愈性的干预措施，所有可用的治疗方法都有副作用，限制了它们的使用。脂肪干细胞（ADSC）治疗是 IBD 的一种有前途的治疗选择。先前的研究表明，人参皂苷（Rg1）通过抑制脂多糖与巨噬细胞上 TLR4 的结合并恢复 Th17/Treg 比值，抑制了像结肠炎这样的炎症性疾病。本研究旨在探讨 Rg1 是否可以增加 ADSC 在葡聚糖硫酸钠（DSS）诱导的结肠炎小鼠模型中的作用。
将 ADSC 静脉接种到 DSS 诱导的结肠炎小鼠中，同时通过口服灌胃给予 Rg1。通过体重、结肠长度和 H&E 染色评估结肠炎症。使用 ELISA 测量血清细胞因子水平。此外，采用流式细胞术测定脾内免疫细胞的百分比和 FMI。通过免疫荧光评估同时给予 Rg1 和 ADSC 对 TLR4-MyD88 信号的影响。
Rg1 和 ADSC 可有效减轻结肠炎引起的体重减轻、结肠长度缩短和组织学评分的影响。与单独给予 ADSC 或 Rg1 相比，联合给予 Rg1 和 ADSC 可降低促炎细胞因子 IL-1β、TNF-α、IL-6、IL-4 和 IL-17A 的血清水平，并上调免疫抑制细胞因子 IL-10 的水平。与单独给予 ADSC 或 Rg1 相比，联合给予 Rg1 和 ADSC 还显著改善了微生物群落的结构。此外，联合治疗可选择性提高脾调节性 T（Treg）细胞水平，下调辅助性 T 细胞 17（Th17）细胞比例，表明肠道内稳态得到恢复。此外，我们发现 ADSC+Rg1 的联合治疗比单独给予 ADSC 或 Rg1 更有效地恢复免疫平衡，表明 Rg1 对肠道微生物群的调节功能可能增强 ADSC 在恢复免疫平衡中的作用。ADSC 联合 Rg1 可能下调 TLR4 和 MyD88 的表达，从而抑制 TLR4-MyD8 信号。免疫荧光结果还表明，Rg-1 和 ADSC 的联合治疗可能优化 IBD 的治疗策略。
本研究发现，与单独给予 ADSC 相比，Rg1 和 ADSC 的联合治疗更有效地缓解了 DSS 诱导的结肠炎小鼠模型的炎症，表明 Rg1 增强了 ADSC 对结肠炎的治疗作用。
