Enhancement of local bone remodeling in osteoporotic rabbits by biomimic multilayered structures on Ti6Al4V implants

Abstract

To enhance long-term survival of titanium implants in patients with osteoporosis, chitosan/gelatin multilayers containing bone morphogenetic protein 2(BMP2) and an antiosteoporotic agent of calcitonin (CT) are deposited on the Ti6Al4V (TC4) implants through layer-by-layer (LBL) electrostatic assembly technique. Here, the obtained titanium alloy implant (TC4/LBL/CT/BMP2) can regulate the release of loaded calcitonin and BMP2 agents in a sustaining manner to accelerate the bone formation and simultaneously inhibit bone resorption. In vitro results show that the bone-related cells on TC4/LBL/CT/BMP2 present the lowest production level of tartrate resistant acid phosphatase (TRAP) but the highest (p < 0.05) level of alkaline phosphatase (ALP) activity, osteocalcin production, mineralization capacity and osteoblast-related gene expression among all groups after treatment for 7 or 21 days, respectively. Besides, in vivo studies of micro-CT analysis, routine histological and immunohistochemical analysis also collectively demonstrate that the TC4/LBL/CT/BMP2 implant can dramatically promote the formation and remodeling of new bone in osteoporotic rabbits after implantation for 30 days and 90 days, respectively. In vivo push-out testing further confirms that the TC4/LBL/CT/BMP2 implant has the highest (p < 0.01) interfacial shear strength and favorable bone-implant osseointegration. Overall, this study establishes a simple and profound methodology to fabricate a biofunctional TC4 implant for the treatment of local osteoporotic fractures in vivo. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1437-1451, 2016.

Synergistic influence of topomimetic and chondroitin sulfate-based treatments on osteogenic potential of Ti-6Al-4V

“…In this study, we proposed biomimetic surface modifications of TA6V by combining (i) topomimetic features that imitate bone surface cavities left after osteoclast resorption and (ii) ECM‐mimetic LbL films that involve chondroitin sulfate A. Such a combination revealed a promising strategy that preserved the intrinsic osteoconductive properties of TA6V and that would improve its osteogenic potential since the adsorbed LbL films will ultimately serve as reservoirs for local delivery of bioactive compound …”

Properties improvement of titanium alloys scaffolds in bone tissue engineering: a literature review

“…For example, bone morphogenetic protein-2 (BMP-2) plays a vital role in the process of osteogenesis (71). Recent research has shown that combined with a slow-release coating constructed by chitosan and other medium composition; it can effectively promote the osteogenesis ability of the titanium alloy scaffold (72)(73)(74). On the other hand, another study showed that BMP-2 inhibits cell proliferation and adhesion at high concentrations (75).…”

Modulation of Osteoclast Interactions with Orthopaedic Biomaterials

“…Decreased periprosthetic bone quality in osteoporotic patients inhibits implants from integrating with the surrounding bone. Surface coating with anti-osteoporotic drugs can impair bone resorption of osteoclasts around host bone tissues, which will benefit osteoporotic patients [ 65 , 66 ]. Bosco et al developed a hydroxyapatite coating incorporated with bisphosphonate anti-osteoporotic drugs on titanium surfaces [ 67 ].…”

“…The electrospray deposition technique was used to deposit a hydroxyapatite coating without compromising the drug activity. Another interesting approach was developed by Huang et al wherein polyelectrolyte multilayer coating techniques were used to immobilize anti-osteoporotic drug, calcitonin, and osteoinductive bone morphogenetic protein 2 (BMP-2) on a titanium surface [ 66 ]. Released calcitonin and BMP-2 from the titanium surface were expected to accelerate bone formation with a concomitant inhibition on bone resorption.…”