Figure 1.

Ischemia/hypoxia induces partial EndMT

(A) Immunofluorescence staining of mouse heart sections isolated from the infarcted border zone 3 and 7 days after MI or sham surgery with antibodies recognizing CD31 (red) and α-SMA (green) was performed. DAPI was used to counterstain the nuclei (blue) (n = 10, scale bars, 100 μm).

(B) The histogram shows the CD31⁺/α-SMA⁺/CD31⁺ cell ratio (%) in the infarcted border zone in each group.

(C) Double immunofluorescence staining for CD31 (green) and α-SMA (red) or VE-cadherin (green) and F-actin (red) in HMEC-1 cells. Nuclei were counterstained with DAPI (blue). HMEC-1 cells were cultured under normoxic or hypoxic conditions for 1–3 days or treated with TGF-β (20 ng/mL) for 3 days (n = 8–10, scale bars, 50 μm).

(D) qRT-PCR analysis of CD31, VE-cadherin, and α-SMA mRNA expression in hypoxic HMEC-1 cells (n = 3).

(E) Western blot analysis of fibronectin, VE-cadherin, CD31, α-SMA, and FSP-1 protein expression relative to that of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in hypoxic HMEC-1 cells (n = 3).

(F) Tube formation assays of hypoxic (0–3 days) or TGF-β-treated (20 ng/mL, 3 days) HMEC-1 cells (n = 5, scale bar, 500 μm).

The data are presented as means ± SEMs. p values were calculated by 1-way ANOVA (B and D). NS indicates no significant difference.