Deficiency of S100 calcium binding protein A9 attenuates vascular dysfunction in aged mice

•S100A9 contributed to aging-related pathologies, such as insulin resistance, oxidative stress and inflammation.•Deficiency of S100A9 alleviated endothelial dysfunction and improved vascular function in aged mice.•TLR4 pathway was involved in the regulation of S100A9-induced cellular senescence in human aortic endothelial cells.