Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand.
Cluster of Excellence on Biodiversity based Economic and Society (B.BES-CMU), Chiang Mai University, Chiang Mai, Thailand.
BMC Complement Med Ther. 2020 Apr 3;20(1):105. doi: 10.1186/s12906-020-02892-w.
Cissus quadrangularis Linn. (CQ) has been used in Indian and Thai traditional medicine for healing bone fractures because of numerous active ingredients in CQ. It is still unclear which compounds are the active ingredients for bone formation.
The molecular docking technique, the ethanolic extraction along with hexane fractionation, and an in vitro experiment with a human osteoblast cell line (MG-63) were used to narrow down the active compounds, to prepare the CQ extract, and to test biological activities, respectively.
The molecular docking technique revealed that quercetin and β-sitosterol had highest and lowest potential to bind to estrogen receptors, respectively. Compared to the crude ethanol extract (P1), the ethanolic fraction (P2) was enriched with rutin and quercetin at 65.36 ± 0.75 and 1.06 ± 0.12 mg/g, respectively. Alkaline phosphatase (ALP) activity was significantly enhanced in osteoblasts exposed to the P2 in both tested concentrations. The amount of hydroxyproline was slightly increased in the P1 treatment, while osteocalcin was inhibited. Moreover, the P2 significantly activated osteoprotegerin (OPG) and inhibited receptor activator of nuclear factor κ ligand (RANKL) expression.
Taken together, the enriched rutin and quercetin fraction of CQ triggered the molecules involved in bone formation and the molecules inhibiting bone resorption.
筋骨草（CQ）在印度和泰国传统医学中被用于治疗骨折，因为 CQ 中含有许多活性成分。目前尚不清楚哪些化合物是形成骨骼的活性成分。
采用分子对接技术、乙醇提取及正己烷分步萃取法，以及体外人成骨细胞系（MG-63）实验，分别对活性化合物进行了筛选、CQ 提取物的制备和生物活性测试。
分子对接技术显示，槲皮素和β-谷甾醇分别具有与雌激素受体结合的最高和最低潜力。与粗乙醇提取物（P1）相比，乙醇级分（P2）中芦丁和槲皮素的含量分别富集至 65.36±0.75 和 1.06±0.12 mg/g。在两种测试浓度下，碱性磷酸酶（ALP）活性在暴露于 P2 的成骨细胞中均显著增强。P1 处理组羟脯氨酸的含量略有增加，而骨钙素受到抑制。此外，P2 还显著激活了护骨素（OPG）并抑制了核因子κ受体激活剂配体（RANKL）的表达。
综上所述，CQ 的富含芦丁和槲皮素的部分触发了参与骨形成和抑制骨吸收的分子。
