Structural state of diaphysis of humeral bone after implantation of hydroxylapatite into tibia and oral administration of calcium medications

BACKGROUND: Osteoporosis and osteopenias are the most common metabolic diseases of skeleton leading to loss of bone mass, which in turn contributes to increase in the incidence of fractures occur against their background. To note, bone fractures often require not only correction of phosphorus-calcium metabolism, but also bone-plastic operations. AIM: To investigate the structure of the middiaphysis of the humeral bone after plastic surgery of the tibia defect with OK-015 material and substantiate the possibilities of correction of its damages by “Biomin MK”. MATERIALS AND METHODS: The experiment involved 210 male laboratory rats with initial body weight from 135 to 145 g: group A — control, in group B perforation of the tibia, in group C filling of the defect with OK-015 material. In the group D after perforation and in the group E after implantation, “Biomin MK” was used intragastrically through a tube at a dose of 90 mg/kg/day. RESULTS: Perforation of the tibia was accompanied by an increase in resorptive processes and inhibition of bone formation in the diaphysis of the humeral bone with maximum deviations by the 30th day after surgery. The implantation of the OK-015 material was accompanied by aggravation of the identified alterations within 15 days, but in the later period, the structure of the middiaphysis recovered faster. With intragastric administration of “Biomin MK” through a tube after the bone plasty, the structure of the middiaphysis of the humeral bones showed more evident changes by the 7th and 15th day, but by the 30th and 60th day after the implantation, the thickness of the layer of the external circumferential lamellae was greater than in group C by the 3.77% and 4.27%, and the thickness of the internal circumferential lamellae and the diameter of osteons by the 60th day — by 3.51%, 6.46% and 18.64%. CONCLUSIONS: The administration of “Biomin MK” during implantation of OK-015 material into the tibia is accompanied by the restoration of the structure of the middiaphysis of the humeral bones, mainly from the 30th to 60th days after the surgery.

Retraction: Ñíguez Sevilla, B., et al. Nurse’s A-Phase–Silicocarnotite Ceramic–Bone Tissue Interaction in a Rabbit Tibia Defect Model. J. Clin. Med. 2019, 8, 1714

In the published paper [...]

Nurse’s A-Phase–Silicocarnotite Ceramic–Bone Tissue Interaction in a Rabbit Tibia Defect Model

Calcium phosphate materials are widely used as bone substitutes due to their bioactive and biodegradable properties. Also, the presence of silicon in their composition seems to improve the bioactivity of the implant and promote bone tissue repair. The aim of this study was to develop a novel ceramic scaffold by partial solid-state sintering method with a composition lying in the field of the Nurse’s A-phase–silicocarnotite, in the tricalcium phosphate–dicalcium silicate (TCP–C2S) binary system. Also, we evaluated its osteogenic and osteoconductive properties after being implanted into tibia defects in New Zealand rabbits. X-ray, microcomputer tomography, and histomorphometry studies demonstrated that this porous ceramic is highly biocompatible and it has excellent osteointegration. The material was being progressively reabsorbed throughout the study and there was no unspecified local or systemic inflammatory response observed. These results suggest that ceramic imitates the physicochemical characteristics of bone substitutes used in bone reconstruction.

Combination of Human Amniotic Fluid Derived-Mesenchymal Stem Cells and Nano-hydroxyapatite Scaffold Enhances Bone Regeneration

BACKGROUND: Human amniotic fluid-derived stem cells (hAF-MSCs) have a high proliferative capacity and osteogenic differentiation potential in vitro. The combination of hAF-MSCs with three-dimensional (3D) scaffold has a promising therapeutic potential in bone tissue engineering and regenerative medicine. Selection of an appropriate scaffold material has a crucial role in a cell supporting and osteoinductivity to induce new bone formation in vivo. AIM: This study aimed to investigate and evaluate the osteogenic potential of the 2nd-trimester hAF-MSCs in combination with the 3D scaffold, 30% Nano-hydroxyapatite chitosan, as a therapeutic application for bone healing in the induced tibia defect in the rabbit. SUBJECT AND METHODS: hAF-MSCs proliferation and culture expansion was done in vitro, and osteogenic differentiation characterisation was performed by Alizarin Red staining after 14 & 28 days. Expression of the surface markers of hAF-MSCs was assessed using Flow Cytometer with the following fluorescein-labelled antibodies: CD34-PE, CD73-APC, CD90-FITC, and HLA-DR-FITC. Ten rabbits were used as an animal model with an induced defect in the tibia to evaluate the therapeutic potential of osteogenic differentiation of hAF-MSCs seeded on 3D scaffold, 30% Nano-hydroxyapatite chitosan. The osteogenic differentiated hAF-MSCs/scaffold composite system applied and fitted in the defect region and non-seeded scaffold was used as control. The histopathological investigation was performed at 2, 3, & 4 weak post-transplantation and scanning electron microscope (SEM) was assessed at 2 & 4 weeks post-transplantation to evaluate the bone healing potential in the rabbit tibia defect. RESULTS: Culture and expansion of 2nd-trimester hAF-MSCs presented high proliferative and osteogenic potential in vitro. Histopathological examination for the transplanted hAF-MSCs seeded on the 3D scaffold, 30% Nano-hydroxyapatite chitosan, demonstrated new bone formation in the defect site at 2 & 3 weeks post-transplantation as compared to the control (non-seeded scaffold). Interestingly, the scaffold accelerated the osteogenic differentiation of AF-MSCs and showed complete bone healing of the defect site as compared to the control (non-seeded scaffold) at 4 weeks post-transplantation. Furthermore, the SEM analysis confirmed these findings. CONCLUSION: The combination of the 2nd-trimester hAF-MSCs and 3D scaffold, 30% Nano-hydroxyapatite chitosan, have a therapeutic perspective for large bone defect and could be used effectively in bone tissue engineering and regenerative medicine.

Effect of Porous Chitosan Microspheres Loaded with Platelet-Rich Plasma and Bone Marrow-Derived Mesenchymal Stem Cells on Regeneration of Tibia Defect

Objective. Repair of bone defects represents a grave clinical challenge because of the tremendous difficulties in the recovery of bone function and regeneration of bone loss. Therefore, we investigated the effects of platelet-rich plasma-loaded (PRP) porous chitosan microspheres (PCMs) on the differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and the proliferation and differentiation potential of BMSCs loaded by PCMs in vitro. We also established the model of bone defect repair in rat tibia to further explore the effects of PCMs loaded with PRP and BMSCs on bone regeneration. Methods. MTT assay was used to detect the proliferative ability of BMSCs after hypoxia/reoxygenation (H/R) treatment and the proliferative ability of BMSCs loaded by PCMs; polymerase chain reaction (PCR) was used to detect the expression of alkaline phosphatase (ALP), type I collagen (Col I), and type II collagen (Col II) in BMSCs after hypoxia and in BMSCs induced by PRP-loaded PCMs; PCR was used to detect the expression of Runt-associated transcription factor 2 (Runx2) and osteocalcin (OC) in the newly generated bone tissue; micro-CT scanning was applied to measure the bone mineral density and bone volume of the newly generated bone tissue in rats. Results. BMSCs still have the normal potential of proliferation and differentiation after H/R treatment. PCMs can provide a larger surface for the attachment of BMSCs, facilitating cell proliferation. Loaded by PCMs, PRP can be slowly released, effectively stimulating the differentiation of BMSCs. PCM/PRP/BMSC composites increased the expression levels of Runx2 and OC in the newly generated bone in rat tibia defect and the bone mineral density. Moreover, the composites improved the rate of regenerated bone volume. Conclusion. The application of PCM/PRP/BMSC composites is promising in the repair of tibia defects.