Gypenoside Inhibits Endothelial Cell Apoptosis in Atherosclerosis by Modulating Mitochondria through PI3K/Akt/Bad Pathway

Figures

• 

  Figure 1. Gypenoside decreases serum lipid levels. The serum lipid profile (TC, TG, LDL-C, and HDL-C levels) was analyzed in the normal, ApoE−/−, gypenoside, and simvastatin groups. (a) TG level, (b) TC level, (c) LDL-C level, and (d) HDL-C level. All results are expressed as the mean ± SD of four different experiments (n = 10). ∗∗P < 0.01 between each group.

• 

  Figure 2. Pathomorphological changes of the aorta. Morphological observations of aortas by H&E staining. (a) Normal group, (b) ApoE−/− group, (c) simvastatin group, and (d) gypenoside group.

• 

  Figure 3. Gypenoside modulates the expression of apoptosis pathway proteins. Gypenoside effectively regulated the expression of apoptotic proteins in the PI3K/Akt/Bad pathway. Gypenoside enhanced the expression of PI3K and p-Akt and markedly downregulated the expression of p-Bad, Cyt-c, cleaved caspase 9, cleaved caspase 3, and PARP. Bar chart results are expressed as the mean ± SD of four different experiments (n = 3). (a) Western blot; (b) bar charts; ∗P < 0.05 and ∗∗P < 0.01 between each group.

• 

  Figure 4. Gypenoside decreases caspase 3 activity and the expression of mitochondrial fission and fusion proteins in the aorta. (a) Caspase 3 activity, as analyzed by the corresponding kit in the normal, ApoE−/−, gypenoside, and simvastatin groups. Results are expressed as the mean ± SD of four different experiments (n = 6). (b, c) Western blot result of DRP1 and MFN2 expression in the aorta; bar chart results are expressed as the mean ± SD of four different experiments (n = 3); ∗P < 0.05 and ∗∗P < 0.01 between each group. (d) Immunofluorescence results of DRP1 and MFN2 expression in the aorta.

• 

  Figure 5. Gypenoside regulates mRNA expression of mitochondrial energy-related genes in the aorta. Mitochondrial energy-related genes Atp12a, Cox5a, Ndufb6, and Sdhc were analyzed by qPCR. (a) Atp12a mRNA is increased in ApoE−/− mice and reduced by gypenoside and simvastatin treatment; (b) Cox5a mRNA is increased in ApoE−/− mice and reduced by gypenoside and simvastatin treatment; (c) Ndufb6 mRNA is increased in ApoE−/− mice and is only reduced by simvastatin treatment; (d) Sdhc mRNA is increased in ApoE−/− mice and reduced by gypenoside and simvastatin treatment. All results are expressed as the mean ± SD of four different experiments (n = 3). ∗∗P < 0.01 between each group.

• 

  Figure 6. Gypenosides, Gypenoside XILX, and Ginsenoside Rb3 modulate expression of PI3K/Akt/Bad pathway proteins and prevent expression of apoptosis proteins in ox-LDL-induced EA.hy926 cells. Gypenosides (Gps), Gypenoside XILX (GpXILX), and Ginsenoside Rb3 (Rb3) effectively regulated expression of PI3K/Akt/Bad pathway proteins. Gps, GpXILX, and Rb3 enhanced expression of PI3K, p-Akt, and p-Bad. All results are expressed as the mean ± SD of four different experiments (n = 3). ∗P < 0.05 and ∗∗P < 0.01 between each group.

• 

  Figure 7. Gypenosides, Gypenoside XILX, and Ginsenoside Rb3 modulate the expression of mitochondrial fission and fusion proteins in ox-LDL-induced EA.hy926 cells. Gypenosides (Gps), Gypenoside XILX (GpXILX), and Ginsenoside Rb3 (Rb3) effectively regulated expression of mitochondrial fission and fusion proteins; Gps markedly downregulated the expression of DRP1 and Mfn2. The results are expressed as the mean ± SD of four different experiments (n = 3). (a) Western blot; (b) bar charts; ∗P < 0.05 and ∗∗P < 0.01 between each group.

• 

  Figure 8. Effect of Gypenosides, Gypenoside XILX, and Ginsenoside Rb3 on mitochondrial respiratory chain complex enzymes I, II, III, IV, and V and ATP content. (a–e) Gps, GpXILX, and Rb3 effectively increase the activity of mitochondrial respiratory chain complex enzymes I, II, III, IV, and V. All results are expressed as the mean ± SD of five different experiments (n = 6); (f) ATP content was measured in EA.hy926 cells. LDL group cells exhibited a decrease in ATP content, which was partially rescued by Gps, GpXILX, and Rb3. All results are expressed as the mean ± SD of five different experiments (n = 3). ∗P < 0.05 and ∗∗P < 0.01 between each group.