In Vivo Evaluation of the Genotoxic Effects of Poly (Butylene adipate-co-terephthalate)/Polypyrrole with Nanohydroxyapatite Scaffolds for Bone Regeneration

Abstract

Here, butylene adipate-co-terephthalate/polypyrrole with nanohydroxyapatite (PBAT/PPy/nHAp) scaffolds were fabricated and characterized. The electrospinning process was carried out using 12 kV, a needle of 23 G, an infusion pump set at 0.3 mL/h, and 10 cm of distance. Afterwards, nHAp was directly electrodeposited onto PBAT/PPy scaffolds using a classical three-electrode apparatus. For in vivo assays (comet assay, acute and chronic micronucleus), 60 male albino Wistar rats with 4 groups were used in each test (n = 5): PBAT/PPy; PBAT/PPy/nHAp; positive control (cyclophosphamide); and the negative control (distilled water). Peripheral blood samples were collected from the animals to perform the comet test after 4 h (for damage) and 24 h (for repair). In the comet test, it was shown that the scaffolds did not induce damage to the % DNA tail and neither for tail length. After the end of 48 h (for acute micronucleus) and 72 h (for chronic micronucleus), bone marrow was collected from each rat to perform the micronucleus test. All of the produced scaffolds did not present genotoxic effects, providing strong evidence for the biological application of PBAT/PPy/nHAp scaffolds.

Nanohydroxyapatite Electrodeposition onto Electrospun Nanofibers: Technique Overview and Tissue Engineering Applications

“…In this context, the electrodeposition of the nHAp coating on the surfaces of polymeric nanofibers emerges as a hopeful strategy to help resolve these issues. Based on the expertise of our research group with nHAp electrodeposition [ 16 , 17 , 47 , 67 ], we developed a protocol to incorporate nHAp particles onto the surface of ultrathin polymer fibers [ 68 , 69 , 70 ].…”

“…The excellent properties of the PBAT/PPy/nHAp nanocomposite were confirmed via in vivo animal tests [ 69 ]. The scaffolds implanted in Wistar rats did not present genotoxic effects, analyzed by comet tests ( Figure 5 a) and micronucleus assays ( Figure 5 b) after acute and chronic exposure.…”

Electrospun Poly(butylene-adipate-co-terephthalate)/Nano-hyDroxyapatite/Graphene Nanoribbon Scaffolds Improved the In Vivo Osteogenesis of the Neoformed Bone

“…Poly (butylene adipate-co-terephthalate) (PBAT) is an interesting biodegradable aliphaticaromatic copolyester to produce scaffolds using electrospinning for BTE application [5][6][7][8][9][10][11][12][13], due to its degradability after a few weeks [14]. PBAT has lower mechanical and osteoindutive and osteocondutive properties and inorganic nanoparticles have been incorporated to improve these properties [14].…”

“…Different strategies evolving synthesis of nHAp, GNR, and nHAp/GNR nanoparticles and their ability to improve biological in vitro and in vivo properties when incorporated in different amounts (from 0.1 to 5%) into different polyesters have been reported by our group [8,[11][12][13]24]. However, an in vivo analysis of bone neoformation obtained by means of several methods such as bone remodeling analysis, microtomography computadorized, radiographical analysis, and biomechanical properties from bone neoformed into bone defects filled with electrospun PBAT containing high loads of nHAp and GNR/nHAp incorporated nanoparticles had not been reported yet.…”

“…However, an in vivo analysis of bone neoformation obtained by means of several methods such as bone remodeling analysis, microtomography computadorized, radiographical analysis, and biomechanical properties from bone neoformed into bone defects filled with electrospun PBAT containing high loads of nHAp and GNR/nHAp incorporated nanoparticles had not been reported yet. Recently, our group demonstrated that conductive PBAT/nHAp (containing polypyrrole) scaffolds were non-genotoxic when implanted in vivo [ 8 ] but no evidence from bone neoformation was evaluated.…”