Correction: Highly porous and elastic aerogel based on ultralong hydroxyapatite nanowires for high-performance bone regeneration and neovascularization.

Correction for 'Highly porous and elastic aerogel based on ultralong hydroxyapatite nanowires for high-performance bone regeneration and neovascularization' by Gao-Jian Huang et al., J. Mater. Chem. B, 2021, 9, 1277-1287, DOI: 10.1039/D0TB02288H.

Highly porous and elastic aerogel based on ultralong hydroxyapatite nanowires for high-performance bone regeneration and neovascularization.

Hydroxyapatite (HAP) is promising for the clinical treatment of bone defects because of its excellent biocompatibility and osteo-conductivity. However, highly porous HAP scaffolds usually exhibit high brittleness and poor mechanical properties, thus organic constituents are usually added to form composite materials. In this work, a highly porous and elastic aerogel made from ultralong HAP nanowires with ultrahigh porosity (∼98.5%), excellent elasticity and suitable porous structure is prepared as the high-performance scaffold for bone defect repair. The highly porous structure of the as-prepared aerogel is beneficial to bone ingrowth and matter/fluid transfer, and the high elasticity can ensure the structural integrity of the scaffold during bone regeneration. Therefore, the HAP nanowire aerogel scaffold can promote the adhesion, proliferation and migration of rat bone marrow derived mesenchymal stem cells (rBMSCs), and elevate the protein expression of osteogenesis and angiogenesis related genes. The in vivo experimental results demonstrate that the HAP nanowire aerogel scaffold is favorable for the ingrowth of new bone and blood vessels, and thus can greatly accelerate bone regeneration and neovascularization. The as-prepared HAP nanowire aerogel scaffold shows promising potential for biomedical applications such as bone defect repair.

Atorvastatin plus therapeutic ultrasound improve postnatal neovascularization in response to hindlimb ischemia via the PI3K-Akt pathway.

Statins and therapeutic ultrasound (TUS) have been shown to ameliorate angiogenesis on ischemic hindlimb animals and promote human umbilical vein endothelial cells (HUVECs) tube formation and proliferation. Here, we evaluate the therapeutic effect of TUS in combination with atorvastatin (Ator) therapy on angiogenesis in hindlimb ischemia and HUVECs. After subjecting excision of the left femoral artery, all mice were randomly distributed to one of four groups: Control; Ator treated mice (Ator); TUS treated mice (TUS); and Ator plus TUS treated mice (Ator+TUS). At day 14 post-surgery, the Ator plus TUS treatment cohort had the greatest blood perfusion, accompanied by elevated capillary density. In vitro, Ator plus TUS augmented tube formation, migration and proliferative capacities of HUVECs. Additionally, the united administration upregulated expression of angiogenic factors phosphorylated Akt (p-Akt), phosphorylated endothelial nitric oxide synthase (p-eNOS), as well as vascular endothelial growth factor (VEGF), both in vivo and in vitro. These benefits could be blocked by either phosphoinositide 3-kinase (PI3K) or eNOS inhibitor. Our data indicated that the united administration could significantly enhance ischemia-mediated angiogenesis and exert a protective effect against ischemic/hypoxia induced damage among HUVECs through up-regulating VEGF expression and activating the PI3K-Akt-eNOS pathway.