FIG. 4.

MPG partially inhibits autophagy after ischemia/reperfusion (I/R). The 3- to 4-month-old wild-type FVB strain mice were subjected to 45-min myocardial ischemia followed by 2-h reperfusion. Antioxidant MPG (100 mg/kg) was injected intraperitoneally 24 h and 1 h before ischemia. (A) Frozen sections were prepared from the mouse hearts and stained with DHE to evaluate the presence of oxidative stress. Scale bar indicates 100 μm. (B) Immunoblots indicating expression of LC3, p62, and tubulin in mouse hearts subjected to I/R in the presence or absence of MPG. (C) Densitometric analyses. (D) Tg-tf-LC3 mice were subjected to I/R in the presence or absence of MPG. Representative images of fluorescent LC3 puncta are shown. Scale bar indicates 50 μm. (E) Mean numbers of green and red dots per cell. (F) Mean numbers of autophagosomes represented by yellow dots in merged images and autolysosomes represented by red dots in merged images per cell. Results represent the means from at least three independent experiments. (G) Immunoblots indicating expression of Beclin-1 and tubulin after I/R in the presence or absence of MPG. (H) Densitometric analyses. Results represent the means from at least three mice each. *p < 0.05; **p < 0.01; N.S., not significant. (To see this illustration in color the reader is referred to the web version of this article at www.liebertonline.com/ars).