Thu Hnin Ei, Hussain Zahid, Mohamed Isa Naina, Shuid Ahmad Nazrun
Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia (The National University of Malaysia), Jalan Yaacob Latif 56000, Cheras, Malaysia.
Department of Pharmaceutics, Faculty of Pharmacy, Universiti Teknologi MARA, Puncak Alam Campus, Bandar Puncak Alam 42300, Selangor, Malaysia.
J Ayurveda Integr Med. 2019 Apr-Jun;10(2):102-110. doi: 10.1016/j.jaim.2017.07.014. Epub 2018 Aug 16.
Eurycoma longifolia (E. longifolia) has gained remarkable recognition due to its promising efficacy of stimulating bone formation in androgen-deficient osteoporosis. Numerous in vivo studies have explored the effects of E. longifolia on osteoporosis; however, the in vitro cellular mechanism was not discovered yet.
The present study was aimed to investigate the effect of E. longifolia on the proliferation, differentiation and maturation of osteoclasts and the translational mechanism of inhibition of osteoclastogenesis using RAW 264.7 cells as an in vitro osteoclastic model.
Having assessed cytotoxicity, the cell viability, cell proliferation rate and osteoclastic differentiation capacity of E. longifolia was investigated by evaluating the tartrate-resistant acid phosphatase (TRAP) activity in receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced osteoclasts. Taken together, the time-mannered expression of osteoclast-related protein biomarkers such as matrix metallopeptidase-9 (MMP-9), cathepsin-K, TRAP, nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), superoxide (free radicals) generation and superoxide dismutase activity were also measured to comprehend the mechanism of osteoclastogenesis.
E. longifolia did not show significant effects on cytotoxicity and cell proliferation of RAW 264.7 cells; however, a significant inhibition of cells differentiation and maturation of osteoclasts was observed. Moreover, a significant down-regulation of RANKL-induced TRAP activity and expression of MMP-9, cathepsin-K, TRAP, NFATc1 and generation of superoxide and enhanced superoxide dismutase activity was observed in E. longifolia treated cell cultures.
We anticipated that E. longifolia that enhances bone regeneration on the one hand and suppresses osteoclast's maturation on the other hand may have great therapeutic value in treating osteoporosis and other bone-erosive diseases such as rheumatoid arthritis and metastasis associated with bone loss.
长叶刺蒺藜（Eurycoma longifolia）因其在雄激素缺乏性骨质疏松症中刺激骨形成的显著功效而备受关注。众多体内研究已探讨了长叶刺蒺藜对骨质疏松症的影响；然而，其体外细胞机制尚未被发现。
本研究旨在以RAW 264.7细胞作为体外破骨细胞模型，研究长叶刺蒺藜对破骨细胞增殖、分化和成熟的影响以及抑制破骨细胞生成的翻译机制。
在评估细胞毒性后，通过评估核因子κB受体激活剂配体（RANKL）诱导的破骨细胞中抗酒石酸酸性磷酸酶（TRAP）活性，研究长叶刺蒺藜的细胞活力、细胞增殖率和破骨细胞分化能力。此外，还测量了破骨细胞相关蛋白生物标志物如基质金属蛋白酶-9（MMP-9）、组织蛋白酶K、TRAP、活化T细胞核因子细胞质1（NFATc1）的时间依赖性表达、超氧化物（自由基）生成和超氧化物歧化酶活性，以了解破骨细胞生成的机制。
长叶刺蒺藜对RAW 264.7细胞的细胞毒性和细胞增殖没有显著影响；然而，观察到对破骨细胞的细胞分化和成熟有显著抑制作用。此外，在长叶刺蒺藜处理的细胞培养物中，观察到RANKL诱导的TRAP活性以及MMP-9、组织蛋白酶K、TRAP、NFATc1的表达显著下调，超氧化物生成减少，超氧化物歧化酶活性增强。
我们预期，长叶刺蒺藜一方面可促进骨再生，另一方面可抑制破骨细胞成熟，在治疗骨质疏松症以及其他骨侵蚀性疾病如类风湿性关节炎和与骨质流失相关的转移方面可能具有巨大的治疗价值。
