Resveratrol Pretreatment Inhibits Myocardial Apoptosis in Rats Following Coronary Microembolization via Inducing the PI3K/Akt/GSK-3β Signaling Cascade

Figure 1. Echocardiography of rats in each group (n = 6, per group). The cardiac function parameters of left ventricle ejection fraction (LVEF), left ventricle fractional shortening (LVFS), left ventricular end-diastolic diameter (LVEDd), and left ventricular end-systolic diameter (LVESd) were measured quantitatively. Data were presented as the mean ± standard deviation (SD). *P < 0.05 versus the sham group; #P < 0.05 versus the CME group; &P < 0.05 versus the CME + RES group.

Figure 2. Resveratrol reduced the serum levels of myocardial injury markers (n = 6, per group). (A) The levels of cTnI in the four groups. (B) The levels of CK-MB in the four groups. (C) The levels LDH of in the four groups. Data were presented as the mean ±SD. *P < 0.05 versus the sham group; #P < 0.05 versus the CME group; &P < 0.05 versus the CME + RES group.

Figure 3. Histopathological examination of myocardial tissues through HE and HBFP staining (×200 magnification; bar = 100 μm) (n = 6, per group). (A) HE staining. Microspheres were observed in the CME, CME+RES, and CME + RES + LY groups but not in the sham category. The arrows indicate the microspheres. (B) HBFP staining. An ischemic myocardium is highlighted in red. The arrows indicate the microinfarct area. Data were presented as the mean ±SD. *P < 0.05 versus the sham group; #P < 0.05 versus the CME group; &P < 0.05 versus the CME + RES group.

Figure 4. Myocardial mitochondrial morphology observed by transmission electron microscopy (magnification ×60,000, scale bar= 500 nm). The black arrow represents the typical vacuolated degeneration and enlarged mitochondria. (n=3, per group).

Figure 5. Detection of myocardial apoptosis through TUNEL staining (×400 magnification; bar = 25 μm) (n=6, per group). The nuclei of normal cardiomyocytes were stained light blue, while apoptotic cardiomyocytes’ nuclei were stained yellow-brown. Arrows indicate the nuclei of apoptotic cardiomyocytes. Data are presented as the mean ±SD. *P < 0.05 versus the sham group; #P < 0.05 versus the CME group; &P < 0.05 versus the CME + RES group.

Figure 6. Pretreatment with resveratrol attenuated CME-induced myocardial apoptosis. (A) The mRNA expression levels of Bcl-2, Bax, and cleaved caspase-3 in cardiac tissues (n=6, per group). (B) The protein expression levels of Bcl-2, Bax, and cleaved caspase-3 in cardiac tissues (n =3, per group). Data were presented as the mean ±SD. *P < 0.05 versus the sham group; #P < 0.05 versus the CME group; &P < 0.05 versus the CME + RES group.

Figure 7. Immunofluorescence staining of Bax, Bcl-2, and cleaved caspase-3 in cardiac tissues. (magnification ×400, scale bar=25 μm) (n=3, per group). (A) IF staining detected the expression of Bax. (B) IF staining detected the expression of Bcl-2. (C) IF staining detected the expression of cleaved caspase-3.

Figure 8. Effect of resveratrol on PI3K/Akt/GSK-3β-associated protein expression in cardiac tissues (n = 3, per group). Data were presented as the mean ±SD. *P < 0.05 versus the sham group; #P < 0.05 versus the CME group; &P < 0.05 versus the CME + RES group.