[Research Advances in Regeneration of Soft Tissue with Small Intestinal Submucosa].

Small intestinal submucosa(SIS)is a natural decellularized extracellular matrix material.Due to its excellent biocompatibility,unique biomechanical properties and biological activity,it has been widely used as a scaffold in regenerative medicine.This article reviews the recent progress in the characterization and medical application of SIS respectively.The specific biological properties of the SIS,as well as its interaction with cells,are highlighted.Some of the SIS products and clinical cases are also reviewed and discussed.

Preclinical Evaluation of Bioactive Small Intestinal Submucosa-PMMA Bone Cement for Vertebral Augmentation.

In vertebroplasty and kyphoplasty, bioinert poly(methyl methacrylate) (PMMA) bone cement is a conventional filler employed for quick stabilization of osteoporotic vertebral compression fractures (OVCFs). However, because of the poor osteointegration, excessive stiffness, and high curing temperature of PMMA, the implant loosens, the adjacent vertebrae refracture, and thermal necrosis of the surrounding tissue occurs frequently. This investigation addressed these issues by incorporating the small intestinal submucosa (SIS) into PMMA (SIS-PMMA). In vitro analyses revealed that this new SIS-PMMA bone cement had improved porous structure, as well as reduced compressive modulus and polymerization temperature compared with the original PMMA. Furthermore, the handling properties of SIS-PMMA bone cement were not significantly different from PMMA. The in vitro effect of PMMA and SIS-PMMA was investigated on MC3T3-E1 cells via the Transwell insert model to mimic the clinical condition or directly by culturing cells on the bone cement samples. The results indicated that SIS addition substantially enhanced the proliferation and osteogenic differentiation of MC3T3-E1 cells. Additionally, the bone cement's biomechanical properties were also assessed in a decalcified goat vertebrae model with a compression fracture, which indicated the SIS-PMMA had markedly increased compressive strength than PMMA. Furthermore, it was proved that the novel bone cement had good biosafety and efficacy based on the International Standards and guidelines. After 12 weeks of implantation, SIS-PMMA indicated significantly more osteointegration and new bone formation ability than PMMA. In addition, vertebral bodies with cement were also extracted for the uniaxial compression test, and it was revealed that compared with the PMMA-implanted vertebrae, the SIS-PMMA-implanted vertebrae had greatly enhanced maximum strength. Overall, these findings indicate the potential of SIS to induce efficient fixation between the modified cement surface and the host bone, thereby providing evidence that the SIS-PMMA bone cement is a promising filler for clinical vertebral augmentation.

Icariin: a potential osteoinductive compound for bone tissue engineering.

To effectively treat bone diseases using bone regenerative medicine, there is an urgent need to develop safe and cheap drugs that can potently induce bone formation. Here, we demonstrate the osteogenic effects of icariin, the main active compound of Epimedium pubescens. Icariin induced osteogenic differentiation of preosteoblastic cells. The combination of icariin and a helioxanthin-derived small compound synergistically induced osteogenic differentiation of MC3T3-E1 cells to a similar extent to bone morphogenetic protein-2. Icariin enhanced the osteogenic induction activity of bone morphogenetic protein-2 in a fibroblastic cell line. Mineralization was enhanced by treatment with a combination of icariin and calcium-enriched medium. The in vivo anabolic effect of icariin was confirmed in a mouse calvarial defect model. Eight-week-old male C57BL/6N mice were transplanted with icariin-calcium phosphate cement (CPC) tablets or CPC tablets only (n = 5 for each), and bone regeneration was evaluated after 4 and 6 weeks. Significant new bone formation was observed in the icariin-CPC group at 4 weeks, and the new bone thickness had increased by 6 weeks. Obvious blood vessel formation was observed in the icariin-induced new bone. Treatment of senescence-accelerated mouse prone 1 and senescence-accelerated mouse prone 6 models further demonstrated that icariin was able to enhance bone formation in vivo. Therefore, icariin is a strong candidate for an osteogenic compound for use in bone tissue engineering.