Fig. 1

Exposure to cigarette smoke causes endothelial apoptosis, glycocalyx impairment and emphysema in mouse. Mice were exposed to air or cigarette smoke for 1 month or 3 months. A Representative haematoxylin and eosin (H&E) staining images of airspace. Alveolar size was measured by mean linear intercept (MLI) (n = 6). Scale bar = 100 μm. B Representative immunofluorescence staining images of cleaved caspase-3 in mice lungs. Nuclei were visualized with 4ʹ,6-diamidino-2-phenylindole (DAPI). White arrowheads indicate the apoptotic endothelial cells. Quantitative analysis of percentage of apoptotic endothelial cells was performed (n = 6). Scale bar = 20 μm. C Representative immunofluorescence staining images of mouse lung sections. Chondroitin sulfate and syndecan-1 antibodies were used as glycocalyx specific antigens, and CD31 was used as the mark of endothelial cell. Nuclei were visualized with DAPI. Scale bar = 20 μm. D Quantitative analysis of fluorescence intensity for heparan sulfate, chondroitin sulfate, syndecan-1 and syndecan-4 (n = 6). *P < 0.05, **P < 0.01. n.s., not significant