College of Pharmacy, Anhui University of Chinese Medicine, Qian Jiang Road 1, Hefei, 230012, China; Key Laboratory of Xin'an Medicine, Ministry of Education, Hefei, 230012, China; Anhui Province Key Laboratory of Research & Development of Chinese Medicine, Hefei, 230012, China.
Key Laboratory of Xin'an Medicine, Ministry of Education, Hefei, 230012, China; Anhui Province Key Laboratory of Research & Development of Chinese Medicine, Hefei, 230012, China; School of Integrated Chinese and Western Medicine, Anhui University of Chinese Medicine, Hefei, 230012, China.
Eur J Pharmacol. 2022 Oct 15;933:175271. doi: 10.1016/j.ejphar.2022.175271. Epub 2022 Sep 13.
Imbalance of macrophage polarization plays a critical role in the progression of rheumatoid arthritis (RA). Geniposide (GE) has been shown to exert anti-inflammatory effects. However, the effect of GE on macrophage polarization remains unclear. Here, we investigated the regulation of GE on the imbalance of macrophage polarization in RA and how it functions. We established a mouse model of collagen-induced arthritis (CIA) and isolated bone marrow-derived macrophages (BMDMs). The results confirmed that pro-inflammatory M1 macrophages were dominant in CIA mice, but the polarization imbalance of macrophages was restored to a certain extent after GE treatment. Furthermore, the membrane targeting of sphingosine kinase 1 (SphK1) was increased in BMDMs of CIA mice, as manifested by increased membrane and cytoplasmic expression of p-SphK1 and high secretion level of sphingosine-1-phosphate (S1P). RAW264.7 cells were stimulated with lipopolysaccharide (LPS)-interferon (IFN)-γ or interleukin (IL)-4 to induce M1 or M2 phenotype, respectively, to revalidate the results obtained in BMDMs. The results again observed SphK1 membrane targeting in LPS-IFN-γ-stimulated RAW264.7 cells. Selective inhibition of SphK1 by PF543 or inhibition of the S1P receptors by FTY720 both restored the proportion of M1 and M2 macrophages in LPS-IFN-γ-stimulated RAW264.7 cells, confirming that SphK1 membrane targeting mediated a proportional imbalance in M1 and M2 macrophage polarization. In addition, GE inhibited SphK1 membrane targeting and kinase activity. Taken together, results confirmed that the inhibition of SphK1 membrane targeting by GE was responsible for restoring the polarization balance of macrophages in CIA mice.
巨噬细胞极化失衡在类风湿关节炎（RA）的进展中起着关键作用。栀子苷（GE）已被证明具有抗炎作用。然而，GE 对巨噬细胞极化的影响尚不清楚。在这里，我们研究了 GE 对 RA 中巨噬细胞极化失衡的调节作用及其作用机制。我们建立了胶原诱导性关节炎（CIA）小鼠模型，并分离了骨髓来源的巨噬细胞（BMDMs）。结果证实，促炎 M1 巨噬细胞在 CIA 小鼠中占优势，但 GE 治疗后，巨噬细胞极化失衡得到一定程度的恢复。此外，SphK1 的膜靶向在 CIA 小鼠的 BMDMs 中增加，表现为 p-SphK1 的膜和细胞质表达增加和 S1P 的高分泌水平。RAW264.7 细胞分别用脂多糖（LPS）-干扰素（IFN）-γ或白细胞介素（IL）-4刺激，以分别诱导 M1 或 M2 表型，以验证在 BMDMs 中获得的结果。结果再次观察到 LPS-IFN-γ 刺激的 RAW264.7 细胞中 SphK1 的膜靶向。SphK1 的选择性抑制（PF543）或 S1P 受体的抑制（FTY720）都恢复了 LPS-IFN-γ 刺激的 RAW264.7 细胞中 M1 和 M2 巨噬细胞的比例，证实 SphK1 的膜靶向介导了 M1 和 M2 巨噬细胞极化的比例失衡。此外，GE 抑制 SphK1 的膜靶向和激酶活性。总之，结果证实，GE 抑制 SphK1 的膜靶向是导致 CIA 小鼠中巨噬细胞极化平衡恢复的原因。
