Isoquercitrin (quercetin-3-O-β-d-glucopyranoside) possess various pharmacological effect as a biologically active compound. The aim of the present study was to investigate its potential effects on the proliferation and osteoblastic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) in vitro and bone formation in the mid-palatal suture during rapid maxillary expansion (RME) in vivo. Cell proliferation of rat BMSCs was detected by cell-counting kit- 8 (CCK-8) assay. Alkaline phosphatase (ALP) activity assay and alizarin red staining were used to evaluate osteogenic differentiation of BMSCs. Furthermore, the expression levels of osteogenesis-related genes including runt-related transcription factor 2 (Runx2), bone sialoprotein (BSP) and activating transcription factor 6 (ATF6) were measured by real-time RT-PCR. In vivo, thirty-six male 6-week-old Wistar rats with or without suture expansion receive systemic administration of isoquercitrin or saline solution. Micro-CT, HE and Masson staining were used to compare the morphological changes between the groups. Bone morphogenetic protein 2 (BMP2) expression in the suture was detected using immunohistochemical staining. Our results showed that isoquercitrin significantly promoted cell proliferation, ALP activity and mineral deposition in the range from 0.01 to 1 μM. Moreover, the expression levels of Runx2, BSP and ATF6 were also upregulated. The measurement of micro-CT imaging and histological examinations demonstrated that daily oral administration of isoquercitrin (10 mg/kg) increased bone formation compared to the other groups. Furthermore, the expression level of BMP2 was also augmented in the presence of isoquercitrin. Consequently, those findings showed that isoquercitrin exerts stimulatory effects on osteogenesis in vitro and in vivo, suggesting that isoquercitrin could be a potential candidate for preventing relapse following RME within palatal sutures.

异槲皮苷（槲皮素-3-O-β- d-吡喃葡萄糖苷）作为生物活性化合物具有多种药理作用。本研究的目的是研究其对骨髓间充质干细胞（BMSCs）的体外增殖和成骨细胞分化以及potential上缝合线在体内上颌快速扩张（RME）期间骨形成的潜在影响。通过细胞计数试剂盒8（CCK-8）测定法检测大鼠BMSC的细胞增殖。碱性磷酸酶（ALP）活性测定和茜素红染色用于评估骨髓间充质干细胞的成骨分化。此外，通过实时RT-PCR测定了与成骨相关的基因的表达水平，包括与矮子相关的转录因子2（Runx2），骨唾液蛋白（BSP）和活化转录因子6（ATF6）。体内，有或没有缝合线扩张的三十六只雄性六周大Wistar大鼠接受异槲皮苷或盐溶液的全身性给药。使用Micro-CT，HE和Masson染色比较两组之间的形态变化。使用免疫组织化学染色检测缝线中骨形态发生蛋白2（BMP2）的表达。我们的结果表明，异槲皮苷显着促进细胞增殖，ALP活性和0.01至1μM范围内的矿物质沉积。此外，Runx2，BSP和ATF6的表达水平也被上调。显微CT成像和组织学检查的测量结果表明，与其他组相比，每天口服异槲皮苷（10 mg / kg）可增加骨形成。此外，在异槲皮苷存在下，BMP2的表达水平也增加。因此，这些发现表明异槲皮苷在体外和体内均对成骨产生刺激作用，表明异槲皮苷可能是预防R缝内RME术后复发的潜在候选药物。