Next Article in Journal
Noninvasive Assessment of Exosome Pharmacokinetics In Vivo: A Review
Next Article in Special Issue
Dry Tablet Formulation of PLGA Nanoparticles with a Preocular Applicator for Topical Drug Delivery to the Eye
Previous Article in Journal
Self-Micellizing Technology Improves the Properties of Ezetimibe and Increases Its Effect on Hyperlipidemic Rats
Previous Article in Special Issue
Microfluidics-Assisted Size Tuning and Biological Evaluation of PLGA Particles
Open AccessArticle

PLGA-BMP-2 and PLA-17β-Estradiol Microspheres Reinforcing a Composite Hydrogel for Bone Regeneration in Osteoporosis

1
Department of Chemical Engineering and Pharmaceutical Technology, University of La Laguna, 38206 La Laguna, Spain
2
Institute of Biomedical Technologies (ITB), University of La Laguna, 38206 La Laguna, Spain
3
Department of Biochemistry, Microbiology, Cell Biology and Genetics, University of La Laguna, 38206 La Laguna, Spain
*
Authors to whom correspondence should be addressed.
Pharmaceutics 2019, 11(12), 648; https://doi.org/10.3390/pharmaceutics11120648
Received: 23 October 2019 / Revised: 21 November 2019 / Accepted: 29 November 2019 / Published: 3 December 2019
(This article belongs to the Special Issue PLGA Based Drug Carrier and Pharmaceutical Applications)
The controlled release of active substances—bone morphogenetic protein 2 (BMP-2) and 17β-estradiol—is one of the main aspects to be taken into account to successfully regenerate a tissue defect. In this study, BMP-2- and 17β-estradiol-loaded microspheres were combined in a sandwich-like system formed by a hydrogel core composed of chitosan (CHT) collagen, 2-hidroxipropil γ-ciclodextrin (HP-γ-CD), nanoparticles of hydroxyapatite (nano-HAP), and an electrospun mesh shell prepared with two external electrospinning films for the regeneration of a critical bone defect in osteoporotic rats. Microspheres were made with poly-lactide-co-glycolide (PLGA) to encapsulate BMP-2, whereas the different formulations of 17β-estradiol were prepared with poly-lactic acid (PLA) and PLGA. The in vitro and in vivo BMP-2 delivered from the system fitted a biphasic profile. Although the in vivo burst effect was higher than in vitro the second phases (lasted up to 6 weeks) were parallel, the release rate ranged between 55 and 70 ng/day. The in vitro release kinetics of the 17β-estradiol dissolved in the polymeric matrix of the microspheres depended on the partition coefficient. The 17β-estradiol was slowly released from the core system using an aqueous release medium (Deff = 5.58·10−16 ± 9.81·10−17m2s−1) and very fast in MeOH-water (50:50). The hydrogel core system was injectable, and approximately 83% of the loaded dose is uniformly discharged through a 20G needle. The system placed in the defect was easily adapted to the defect shape and after 12 weeks approximately 50% of the defect was refilled by new tissue. None differences were observed between the osteoporotic and non-osteoporotic groups. Despite the role of 17β-estradiol on the bone remodeling process, the obtained results in this study suggest that the observed regeneration was only due to the controlled rate released of BMP-2 from the PLGA microspheres. View Full-Text
Keywords: BMP-2-microspheres; hydrogel system; 17-βestradiol release; bone regeneration; osteoporosis; poly-lactide-co-glycolide; polylactic acid BMP-2-microspheres; hydrogel system; 17-βestradiol release; bone regeneration; osteoporosis; poly-lactide-co-glycolide; polylactic acid
Show Figures

Graphical abstract

MDPI and ACS Style

García-García, P.; Reyes, R.; Segredo-Morales, E.; Pérez-Herrero, E.; Delgado, A.; Évora, C. PLGA-BMP-2 and PLA-17β-Estradiol Microspheres Reinforcing a Composite Hydrogel for Bone Regeneration in Osteoporosis. Pharmaceutics 2019, 11, 648.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop