Zinc-aspirin preconditioning reduces endothelial damage of arterial grafts in a rodent model of revascularization

Figures

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  Figure 1. Flowchart of the applied experimental design. ntCo: non-transplanted control group; tCo, transplanted control group; Asp, aspirin group; ZnAsp, zinc-aspirin group.

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  Figure 2. Result of the organ bath functional measurement. Significantly better vasorelaxation activity was found in the aspirin group (Asp) compared to the transplanted control (tCo) group, but zinc-aspirin pretreatment (ZnAsp) resulted in an even better graft protection than treatment with aspirin alone. [*p < 0.05 vs. non-transplanted control group (ntCo), #p < 0.05 vs. tCo, łp < 0.05 vs. Asp].

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  Figure 3. (A) aspirin (Asp) significantly decreased the nitro-oxidative stress caused by ischemia-reperfusion injury; however, zinc-aspirin (ZnAsp) showed an even greater protective effect. (*p < 0.05 vs. non-transplanted control group (ntCo), #p < 0.05 vs. transplanted control group (tCo), łp < 0.05 vs. Asp). (B) The representative immunohistochemistry images demonstrate the expression of nitrotyrosine, shown by the brown color in the aortic wall.

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  Figure 4. (A) caspase-3 immunoreactivity significantly increased following transplantation in transplanted control (tCo) grafts compared to non-transplanted control group (ntCo) as a result of increased apoptosis signaling. This mechanism was prevented by aspirin pretreatment (Asp), however, zinc-aspirin (ZnAsp) demonstrated a significantly better preventive effect. (*p < 0.05 vs. ntCo, #p < 0.05 vs. tCo, łp < 0.05 vs. Asp). (B) The apoptosis marker caspase-3 is marked with brown color in the representative immunohistochemistry images. (C) The TUNEL positive cells were considered as apoptotic cells. Apoptosis inhibition was detected in the aspirin (Asp) and zinc-aspirin (ZnAsp) groups compared to transplanted control group (tCo), however, zinc-aspirin treatment resulted in a significantly decreased apoptosis compared to the Asp group. [*p < 0.05 vs. non-transplanted control group (ntCo), #p < 0.05 vs. tCo, łp < 0.05 vs. Asp]. (D) Representative micrographs of aortic tissue show red nuclei with fragmented DNA, visualized by TUNEL staining, and blue nuclei representing 4′,6-diamino-2-phenylindole staining.

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  Figure 5. (A) CD-31 positive area, reflecting the uninjured endothelium surface was significantly more extensive in the aspirin (Asp) and zinc-aspirin (ZnAsp) groups compared to the transplanted control (tCo) group. Significant difference was also found between the Asp and ZnAsp groups, as zinc-aspirin showed a more intensive endothelium protective effect. [*p < 0.05 vs. non-transplanted control group (ntCo), #p < 0.05 vs. tCo, łp < 0.05 vs. Asp]. (B) The uninjured endothelium is labelled with brown color in the representative immunohistochemical images.