Utilização de nanopartículas fosfatadas contendo estrôncio associadas ao ácido hialurônico como estratégia para acelerar o reparo ósseo

Abstract

Bone tissue is constantly remodeling, correcting disturbances in its extracellular matrix and maintaining local homeostasis. When injured, it can reactivate ontogenetic pathways related to bone development, which promotes tissue regeneration. The development of biomaterials to accelerate bone repair is essential for the treatment of patients who are victims of orthopedic and oncological trauma and those with congenital diseases of the bone tissue. The use of substances that mimic its extracellular, organic or mineral matrix is one of the modalities that present the best results. In the present study, the objective is to evaluate the use of a new nanoparticle based on strontium-containing phosphate (NPC-Sr), as a strategy to enhance bone regeneration, alone or associated with hyaluronic acid (HY). To evaluate the effects of HY, NPC-Sr and the association HY+NPC-Sr, a model of non-critical bone defect in the tibia of rats was used. The animals were divided into four groups: (i) control/carbopol rats; (ii) HY-treated rats (1%); (iii) mice treated with NPC-Sr (0.5 mg/ml) and (iv) mice treated with HY+NPC-Sr. After creating the bone defect using a twist drill, treatment was administered to the injury site. On the seventh day of the experiment, the animals were sacrificed, and the tibiae processed for histological and morphometric evaluation with quantification of the percentage of bone trabeculae. Morphometric evaluation showed that treatment with HY (21.8 ± 2.7%), NPC-Sr (20.4 ± 5.5%) or HY+NPC-Sr (19.7 ± 3.7) were able to of accelerating the bone repair process, when compared to the control group (13.5 ± 2.2%). Histological analysis showed an increase in trabecular formation in animals treated with the materials, as well as greater maturity of newly formed bone tissue. In both analyses, there was no significant difference between the three treatments. Based on these results, it is concluded that HY and NPC-Sr could accelerate bone repair in non-critical defects in rat tibias and that the association of the two compounds has no summative or deleterious effect.