Improved in vitro angiogenic behavior on anodized titanium dioxide nanotubes

Abstract

BackgroundNeovascularization over dental implants is an imperative requisite to achieve successful osseointegration onto implanted materials. The aim of this study was to investigate the effects on in vitro angiogenesis of anodized 70 nm diameter TiO2 nanotubes (NTs) on Ti6Al4V alloy synthesized and disinfected by means of a novel, facile, antibacterial and cost-effective method using super oxidized water (SOW). We also evaluated the role of the surface roughness and chemical composition of materials of materials on angiogenesis.MethodsThe Ti6Al4V alloy and a commercially pure Ti were anodized using a solution constituted by SOW and fluoride as electrolyte. An acid-etched Ti6Al4V was evaluated to compare the effect of micro-surface roughness. Mirror-polished materials were used as control. Morphology, roughness, chemistry and wettability were assessed by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy, atomic force microscopy, energy dispersive X-ray spectroscopy (EDX) and using a professional digital camera. Bovine coronary artery endothelial cells (BCAECs) were seeded over the experimental surfaces for several incubation times. Cellular adhesion, proliferation and monolayer formation were evaluated by means of SEM. BCAEC viability, actin stress fibers and vinculin cellular organization, as well as the angiogenic receptors vascular endothelial growth factor 2 (VEGFR2) and endothelial nitric oxide synthase (eNOS) were measured using fluorescence microscopy.ResultsThe anodization process significantly increased the roughness, wettability and thickness of the oxidized coating. EDX analysis demonstrated an increased oxygen (O) and decreased carbon (C) content on the NTs of both materials. Endothelial behavior was solidly supported and improved by the NTs (without significant differences between Ti and alloy), showing that endothelial viability, adhesion, proliferation, actin arrangement with vinculin expression and monolayer development were evidently stimulated on the nanostructured surface, also leading to increased activation of VEGFR2 and eNOS on Ti6Al4V-NTs compared to the control Ti6Al4V alloy. Although the rougher alloy promoted BCAECs viability and proliferation, filopodia formation was poor.ConclusionThe in vitro results suggest that 70 nm diameter NTs manufactured by anodization and cleaned using SOW promotes in vitro endothelial activity, which may improve in vivo angiogenesis supporting a faster clinical osseointegration process.

Nanotubular TiO₂ regulates macrophage M2 polarization and increases macrophage secretion of VEGF to accelerate endothelialization via the ERK1/2 and PI3K/AKT pathways

“…6 Moreover, TiO 2 nanotubes can reduce the inflammatory response of macrophages by inhibiting the nuclear factor-κB (NF-κB) pathway, 7 and TiO 2 is easily formed on the material surface through a simple electrochemical process. 8,9 Interestingly, highly ordered TiO 2 nanotubes with a diameter of about 70 nm improve human umbilical vein endothelial cell (HUVEC) adhesion, proliferation, and angiogenesis, 10 indicating that the morphology of biomaterials is relevant to bodily responses. Although endothelial cells can be guided by titanium nanotubes, [11][12][13] the interaction between the effects of nanotubes on macrophages and the functions of endothelial cells remains unclear.…”

Самоорганизация Биоактивного Наноструктурированного Оксидного Слоя На Поверхности Спеченного Порошка Губчатого Титана При Электрохимическом Анодировании

“…К настоящему моменту был выполнен ряд исследований, выявивших положительное воздействие нанотрубчатого TiO 2 как на рост клеток, так и на скорость образования гидроксиапатита [7,9,10]. Формирование в результате анодирования нанотрубча-того слоя TiO 2 приводит к увеличению удельной по-верхности имплантата, улучшает коррозионную стой-кость, способствует гидрофильности и, таким образом, значительно улучшает биосовместимость по сравнению с немодифицированными поверхностями [15].…”

“…К настоящему моменту был выполнен ряд исследований, выявивших положительное воздействие нанотрубчатого TiO 2 как на рост клеток, так и на скорость образования гидроксиапатита [7,9,10]. Формирование в результате анодирования нанотрубча-того слоя TiO 2 приводит к увеличению удельной по-верхности имплантата, улучшает коррозионную стой-кость, способствует гидрофильности и, таким образом, значительно улучшает биосовместимость по сравнению с немодифицированными поверхностями [15].Известен ряд работ, посвященных формированию био-активных оксидных покрытий на поверхности так на-зываемых пористых титановых матриц (porous titanium scaffold), полученных различными методами [2,3]. С этой целью применялось как плазменно-электролитическое оксидирование (ПЭО) [16,17], так и электрохимиче-ское анодирование [10].…”

Titanium Nanorods Loaded PCL Meshes with Enhanced Blood Vessel Formation and Cell Migration for Wound Dressing Applications

“…Although excessive generation of ROS can cause harmful effects, ROS at optimum dose exerts favorable role in angiogenesis and wound healing . Studies also showed that anodized titanium dioxide nanostructures on implants enhance angiogenesis related cellular responses such as higher endothelial cell adhesion, viability, and proliferation . However, a detailed investigation on the angiogenic potential of TiO 2 nanostructures yet to be explored using in ovo or in vivo models.…”