Figure 1.

Effect of MSCs on oxLDL-induced human umbilical vein endothelial cell (HUVEC) damage. (A): Transwell migration assays. HUVECs were seeded in the lower wells without (CTR) or with oxLDL treatment (50 μg/ml) in the absence or presence of antibodies against SDF-1 (oxLDL/anti-SDF-1) or CXCR4 (oxLDL/anti-CXCR4), whereas MSCs were seeded in the upper wells and assayed at 24 hours. Top: Representative views of the fields in Transwell membranes, showing the stained MSCs that migrated to the lower membrane side of Transwells. Bottom: Quantification of the number of migrated MSCs per high power field. Data are the average numbers of migratory cells in eight high-power fields (×200). Each experiment was performed in triplicate. ∗∗, p < .01 versus CTR; #, p < .05 versus oxLDL. (B): HUVECs were treated with the indicated concentrations of oxLDL for 24 hours, followed by quantitative reverse transcription-polymerase chain reaction analysis. (C, D): HUVECs (1.5 × 10⁴ cells) were treated without or with 50 μg/ml oxLDL in the absence or presence of indirect coculture with MSCs (5 × 10³ cells) for 24 hours, followed by Western blot analysis (C) and assay of the culture supernatants (D) for determining the NO production by using Griess method (n = 6 in each group). ∗∗, p < .01 versus CTR or oxLDL. Abbreviations: CTR, control; CXCR4, C-X-C chemokine receptor type 4; eNOS, endothelial nitric-oxide synthase; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; MSC, mesenchymal stem cell; oxLDL, oxidized low-density lipoprotein; p-Akt, phospho-Akt; p-eNOS, phospho-eNOS; SDF-1, stromal cell-derived factor 1.