Análise dos efeitos da pentoxifilina e tocoferol, isolados e em associação, em cultivo de osteoblastos: uma investigação in silico dos possíveis mecanismos de ação

Abstract

Pentoxifylline and Tocopherol are drugs used in the treatment of osteoradionecrosis and drug-induced osteonecrosis, with beneficial effects on bone tissue. However, there is a lack of knowledge regarding the action of these drugs on bone cells and their molecular interactions in protein sites involved in bone formation. Thus, this study aimed to evaluate the in silico and in vitro effect of the drugs Pentoxifylline and/or Tocopherol and to propose alternative ligands based on molecular docking analysis. Four experimental groups were used: Control (C), Pentoxifylline (P), Tocopherol (T) and Pentoxifylline+Tocopherol (PT). The effect of these drugs on cytotoxicity and osteoblast activation was investigated using the MTT assay, Tripan Blue assay, Von Kossa mineralization assay and bone alkaline phosphatase (ALP) measurement. The chemical structure of the drugs was used to assess the binding affinity (kcal/mol-1) to the ligands: morphogenetic protein 2 (BMP-2), nuclear factor kappa B activating receptor (RANLK), its ligand (RANKL), osteoprotegerin (OPG), Wnt3a and Frizzled through molecular docking. In the MTT test with 24 h of treatment, none of the treatments showed a cytotoxic effect or suggestive of proliferation. After 48h, the T(5 μM) and PT(2.5 μM) groups showed significant differences suggestive of proliferation in relation to the C group. At 72 h, when compared to the C group, there were statistical differences suggestive of proliferation in the 3 groups P, T and PT. In the Tripan Blue trial, none of the treatments showed a cytotoxic effect. In the measurement of ALP levels, the P and PT groups (10 μM), after 72 h of treatment, showed a significant increase in ALP levels compared to the C group. In the 21-day Von Kossa mineralization assay, the P groups and PT (10 μM) showed a significant increase in crystals compared to group C. It was observed that the drugs Pentoxifylline and Tocopherol had a lower interaction strength (<-6.0 kcl/mol-1) with Wnt3a and Frizzled, when compared to the others binders. It was concluded that the association of Pentoxifylline and Tocopherol drugs promotes the activation of murine osteoblasts and that they present moderate or strong binding affinity with BMP-2, RANK/RANKL and RANKL/OPG, suggesting a synergistic or additive activation which may be promising for the treatment of bone diseases.