Department of Surgery, The University of Alberta, Edmonton, Alberta, Canada.
The National Key Discipline and the Orthopedic Laboratory, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China.
Stem Cell Res Ther. 2019 Aug 29;10(1):277. doi: 10.1186/s13287-019-1375-x.
Chrysosplenetin is an O-methylated flavonol compound isolated from the plant Chamomilla recutita and Laggera pterodonta. The aim of our research is to evaluate the function of Chrysosplenetin on osteogenesis of human-derived bone marrow stromal cells (hBMSCs) and inhibition of estrogen deficiency-induced osteoporosis via the Wnt/β-catenin signaling pathway.
hBMSCs are cultured and treated by Chrysosplenetin in the absence or presence of Wnt inhibitor dickkopf-related protein 1 (DKK1) or bone morphogenetic protein 2 (BMP2) antagonist Noggin. RT-qPCR is taken to identify the genetic expression of target genes of Wnt/β-catenin pathway and osteoblast-specific markers. The situation of β-catenin is measured by western blot and immunofluorescence staining. An ovariectomized (OVX) mouse model is set up to detect the bone loss suppression by injecting Chrysosplenetin. Micro-CT and histological assay are performed to evaluate the protection of bone matrix and osteoblast number. Serum markers related with osteogenesis are detected by ELISA.
In the present study, it is found that Chrysosplenetin time-dependently promoted proliferation and osteoblastogenesis of hBMSCs reaching its maximal effects at a concentration of 10 μM. The expressions of target genes of Wnt/β-catenin pathway and osteoblast-specific marker genes are enhanced by Chrysosplenetin treatment. Furthermore, the phosphorylation of β-catenin is decreased, and nuclear translocation of β-catenin is promoted by Chrysosplenetin. Osteogenesis effects mentioned above are founded to be blocked by DKK1 or BMP2 antagonist Noggin. In vivo study reveals that Chrysosplenetin prevents estrogen deficiency-induced bone loss in OVX mice detected by Micro-CT, histological analysis, and ELISA.
Our study demonstrates that Chrysosplenetin improves osteoblastogenesis of hBMSCs and osteogenesis in estrogen deficiency-induced bone loss by regulating Wnt/β-catenin pathway.
芹黄素是一种从植物春黄菊和拉格帕龙中分离出来的 O-甲基化黄酮醇化合物。我们的研究目的是通过 Wnt/β-连环蛋白信号通路评估芹黄素对人源性骨髓基质细胞（hBMSCs）成骨和抑制雌激素缺乏诱导的骨质疏松症的功能。
用芹黄素处理和不处理 hBMSCs，并用 Wnt 抑制剂 Dickkopf 相关蛋白 1（DKK1）或骨形态发生蛋白 2（BMP2）拮抗剂 Noggin 处理。通过 RT-qPCR 鉴定 Wnt/β-连环蛋白通路和成骨细胞特异性标记物的靶基因的基因表达。通过 Western blot 和免疫荧光染色测定 β-连环蛋白的情况。建立去卵巢（OVX）小鼠模型，通过注射芹黄素检测骨丢失的抑制情况。通过 Micro-CT 和组织学检测评估对骨基质和成骨细胞数量的保护。通过 ELISA 检测与成骨相关的血清标志物。
在本研究中，发现芹黄素时间依赖性地促进 hBMSCs 的增殖和成骨作用，在 10μM 浓度下达到最大效果。芹黄素处理后，Wnt/β-连环蛋白通路的靶基因和成骨细胞特异性标记基因的表达增强。此外，芹黄素降低了β-连环蛋白的磷酸化，促进了β-连环蛋白的核转位。上述成骨作用被 DKK1 或 BMP2 拮抗剂 Noggin 阻断。体内研究表明，芹黄素通过 Micro-CT、组织学分析和 ELISA 检测到可预防 OVX 小鼠雌激素缺乏引起的骨丢失。
我们的研究表明，芹黄素通过调节 Wnt/β-连环蛋白通路改善 hBMSCs 的成骨作用和雌激素缺乏诱导的骨丢失中的成骨作用。
