Nabiyouni Maryam, Ren Yufu, Bhaduri Sarit B
Department of Bioengineering, University of Toledo, Toledo, OH, USA.
Department of Mechanical, Industrial and Manufacturing Engineering, University of Toledo, Toledo, OH, USA.
Mater Sci Eng C Mater Biol Appl. 2015;52:11-7. doi: 10.1016/j.msec.2015.03.032. Epub 2015 Mar 24.
As biocompatible materials, magnesium phosphates have received a lot of attention for orthopedic applications. During the last decade multiple studies have shown advantages for magnesium phosphate such as lack of cytotoxicity, biocompatibility, strong mechanical properties, and high biodegradability. The present study investigates the role of Mg(+2) and Ca(+2) ions in the structure of magnesium phosphate and calcium phosphate nanoparticles. To directly compare the effect of Mg(+2) and Ca(+2) ions on structure of nanoparticles and their biological behavior, three groups of nanoparticles including amorphous magnesium phosphates (AMPs) which release Mg(+2), calcium magnesium phosphates (CMPs) which release Mg(+2) and Ca(+2), and hydroxyapatites (HAs) which release Ca(+2) were studied. SEM, TEM, XRD, and FTIR were used to evaluate the morphology, crystallinity, and chemical properties of the particles. AMP particles were homogeneous nanospheres, whereas CMPs were combinations of heterogeneous nanorods and nanospheres, and HAs which contained heterogeneous nanosphere particles. Cell compatibility was monitored in all groups to determine the cytotoxicity effect of particles on studied MC3T3-E1 preosteoblasts. AMPs showed significantly higher attachment rate than the HAs after 1 day and both AMPs and CMPs showed significantly higher proliferation rate when compared to HAs after 7days. Gene expression level of osteoblastic markers ALP, COL I, OCN, OPN, RUNX2 were monitored and they were normalized to GAPDH housekeeping gene. Beta actin expression level was monitored as the second housekeeping gene to confirm the accuracy of results. In general, AMPs and CMPs showed higher expression level of osteoblastic genes after 7 days which can further confirm the stimulating role of Mg(+2) and Ca(+2) ions in increasing the proliferation rate, differentiation, and mineralization of MC3T3-E1 preosteoblasts.
作为生物相容性材料，磷酸镁在骨科应用中受到了广泛关注。在过去十年中，多项研究表明了磷酸镁的优势，如无细胞毒性、生物相容性、强大的机械性能和高生物降解性。本研究调查了Mg(+2)和Ca(+2)离子在磷酸镁和磷酸钙纳米颗粒结构中的作用。为了直接比较Mg(+2)和Ca(+2)离子对纳米颗粒结构及其生物学行为的影响，研究了三组纳米颗粒，包括释放Mg(+2)的无定形磷酸镁（AMP）、释放Mg(+2)和Ca(+2)的钙镁磷酸盐（CMP）以及释放Ca(+2)的羟基磷灰石（HA）。使用扫描电子显微镜（SEM）、透射电子显微镜（TEM）、X射线衍射（XRD）和傅里叶变换红外光谱（FTIR）来评估颗粒的形态、结晶度和化学性质。AMP颗粒为均匀的纳米球，而CMP是异质纳米棒和纳米球的组合，HA则包含异质纳米球颗粒。监测所有组的细胞相容性，以确定颗粒对所研究的MC3T3-E1前成骨细胞的细胞毒性作用。1天后，AMP的附着率显著高于HA，7天后，与HA相比，AMP和CMP的增殖率均显著更高。监测成骨细胞标志物碱性磷酸酶（ALP）、I型胶原蛋白（COL I）、骨钙素（OCN）、骨桥蛋白（OPN）、RUNX2的基因表达水平，并将其标准化为管家基因甘油醛-3-磷酸脱氢酶（GAPDH）。监测β-肌动蛋白表达水平作为第二个管家基因，以确认结果的准确性。总体而言，7天后AMP和CMP显示出更高的成骨基因表达水平，这可以进一步证实Mg(+2)和Ca(+2)离子在提高MC3T3-E1前成骨细胞的增殖率、分化和矿化方面的促进作用。
