Guanxin Shutong capsule (GXSTC) is a Chinese medicinal formula that has been used clinically for the treatment of
chest pain, depression, palpitation and
cardiovascular diseases in China for almost 10 years. The aim of the present study was to investigate the protective mechanisms against oxidative stress and apoptosis that GXSTC exhibits in the hearts of rats with
myocardial ischemia (MI).
Infarct size and the levels of marker
enzymes, including serum
creatine kinase-
isoenzyme (CK-MB),
lactate dehydrogenase (LDH) and
glutamate oxaloacetic
transaminase (GOT), as well as the levels of
nitric oxide (NO) and
NO synthase (NOS) in the heart were measured by biochemical analysis assays. Levels of the
antioxidants superoxide dismutase (SOD),
catalase (CATA), and
glutathione (GSH), and the oxidative stress marker
malondialdehyde (MDA), were also determined. Following a 6-week period of
ischemia, myocardial apoptosis, as well as the
protein and
mRNA expression of
NADPH oxidase, was evaluated. Myocardial
NADPH oxidase activity was measured by
protein expression of p47phox and gp91phox using western blot analysis and
mRNA expression of p22phox, p47phox,
p67phox and gp91phox using reverse transcription polymerase chain reaction. The results showed that daily oral treatment of the rats with GXSTC reduced
infarct size, myocardial apoptosis, the levels of serum MDA, LDH, CK-MB and GOT and heart GOT, and increased the activities of total SOD, CATA, NOS and the levels of NO and GSH compared with those in vehicle-treated MI model rats. Administration of GXSTC for 6 weeks also reduced the
mRNA expression of the
NADPH oxidase subunits p47phox and gp91phox
protein, as well as the expression of Bax and
caspase-3 proteins. By contrast, Bcl-2
protein expression increased. In conclusion, the results demonstrate that GXSTC attenuates myocardial injury via antioxidative and antiapoptotic effects.