Qu Liu, Dubey Nileshkumar, Ribeiro Juliana S, Bordini Ester A F, Ferreira Jessica A, Xu Jinping, Castilho Rogerio M, Bottino Marco C
Department of Cariology, Restorative Sciences and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, USA; Department of Endodontics, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China.
Department of Cariology, Restorative Sciences and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, USA.
J Mech Behav Biomed Mater. 2021 Apr;116:104293. doi: 10.1016/j.jmbbm.2020.104293. Epub 2020 Dec 28.
The aim of this investigation was to engineer metformin (MF)-loaded mesoporous silica nanospheres (MSNs)-laden gelatin methacryloyl (GelMA) photocrosslinkable hydrogels and test their effects on the mechanical properties, swelling ratio, drug release, cytocompatibility, and osteogenic differentiation of stem cells from human exfoliated deciduous teeth (SHEDs). As-received and carboxylated MSNs (MSNs-COOH) were characterized by scanning and transmission electron microscopies (SEM and TEM), as well as Fourier-transform infrared spectroscopy (FTIR) prior to hydrogel modification. MF-MSNs-COOH were obtained by loading MF into MSNs at a 1:1 mass ratio. Upon MSNs-COOH laden-hydrogels fabrication, the mechanical properties, swelling ratio and MF release were evaluated. SHEDs were seeded on the hydrogels and cytocompatibility was examined. The effects of the MF-MSNs-COOH/GelMA on the osteogenic differentiation of SHEDs were measured by ALP activity, Alizarin Red assay, and Real-time PCR. Statistics were performed using one-way ANOVA (α = 0.05). Morphological (SEM and TEM) analyses of pristine and carboxylated MSNs revealed a mean particle size of 200 nm and 218 nm, respectively. Importantly, an intrinsic nanoporous structure was noticed. Incorporation of MSNs-COOH at 1.5 mg/mL in GelMA led to the highest compressive modulus and swelling ratio. The addition of MSNs-COOH (up to 3 mg/mL) in GelMA did not impact cell viability. The presence of MF in MSNs-COOH/GelMA significantly promoted cell proliferation. Significant upregulation of osteogenic-related genes (except OCN) were seen for modified (MSNs-COOH and MF-MSNs-COOH) hydrogels when compared to GelMA. Altogether, the engineered MF-MSNs-COOH/GelMA shows great promise in craniomaxillofacial applications as an injectable, cell-free and bioactive therapeutics for bone regeneration.
本研究的目的是制备负载二甲双胍（MF）的介孔二氧化硅纳米球（MSNs）负载的甲基丙烯酰化明胶（GelMA）光交联水凝胶，并测试其对人乳牙脱落干细胞（SHEDs）的力学性能、溶胀率、药物释放、细胞相容性和成骨分化的影响。在进行水凝胶改性之前，通过扫描电子显微镜和透射电子显微镜（SEM和TEM）以及傅里叶变换红外光谱（FTIR）对原样接收的和羧基化的MSNs（MSNs-COOH）进行表征。通过将MF以1:1的质量比负载到MSNs中获得MF-MSNs-COOH。在制备负载MSNs-COOH的水凝胶后，评估其力学性能、溶胀率和MF释放。将SHEDs接种在水凝胶上并检查细胞相容性。通过碱性磷酸酶（ALP）活性、茜素红测定和实时聚合酶链反应（Real-time PCR）测量MF-MSNs-COOH/GelMA对SHEDs成骨分化的影响。使用单因素方差分析（α = 0.05）进行统计学分析。对原始和羧基化MSNs的形态学（SEM和TEM）分析显示，平均粒径分别为200 nm和218 nm。重要的是，观察到了固有的纳米多孔结构。在GelMA中加入1.5 mg/mL的MSNs-COOH可导致最高的压缩模量和溶胀率。在GelMA中加入MSNs-COOH（高达3 mg/mL）不影响细胞活力。MSNs-COOH/GelMA中MF的存在显著促进细胞增殖。与GelMA相比，改性（MSNs-COOH和MF-MSNs-COOH）水凝胶中与成骨相关的基因（除骨钙素外）有显著上调。总之，工程化的MF-MSNs-COOH/GelMA作为一种可注射、无细胞且具有生物活性的骨再生治疗剂，在颅颌面应用中显示出巨大的潜力。
