Objective

2

To explore the mechanism of Wutou Chishizhi Wan in regulating autophagy and phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt）/glycogen synthase kinase-3

β

（GSK-3

β

） signaling pathway in rats with myocardial ischemia-reperfusion injury （MIRI）.

Method

2

Sixty male SD rats were randomly assigned into the normal group （normal saline）， model group （normal saline）， positive control （trimetazidine， 5.4 mg·kg

-1

） group， and low-， medium-， and high-dose （1.63， 4.9， 14.7 g·kg

-1

， respectively） Wutou Chishizhi Wan groups， with 10 rats in each group. The rats in other groups except the normal group underwent left anterior descending coronary artery ligation for modeling. Electrocardiogram was employed to detect the ST-segment elevation to evaluate the modeling. Hematoxylin-eosin （HE） staining was performed to reveal the damage of myocardial tissue. The levels of aspartate aminotransferase （AST） and creatine kinase （CK） were determined by colorimetry， and those of cardiac troponin T （cTnT） and myoglobin （MYO） by enzyme-linked immunosorbent assay （ELISA）. Western blot was carried out to determine the protein levels of microtubule-associated proteins 1 light chain 3 （LC3）， autophagy-related gene Beclin-1， PI3K， Akt， GSK-3

β

， p-GSK-3

β

， and p-Akt.

Result

2

Compared with the normal group， the modeling elevated the serum levels of AST， CK， cTnT， and MYO （

P

<

0.01）， destroyed the arrangement of myocardial cells abd nucle， twisted and broken myocardial fibers， up-regulated the protein levels of LC3Ⅱ/Ⅰ and Beclin-1 （

P

<

0.01）， and down-regulated the protein levels of PI3K， p-Akt， and p-GSK-3

β

（

P

<

0.01）. Compared with the model group， trimetazidine and Wutou Chishizhi Wan （all the doses） lowered the levels of AST， CK， cTnT， and MYO in serum （

P

<

0.01）， restored the arrangement of myocardial cells and muscle fibers， reduced necrosis， down-regulated the protein level of Beclin-1 （

P

<

0.01）， and up-regulated the protein levels of PI3K， p-Akt， and p-GSK-3

β

（

P

<

0.01）. Additionally， Wutou Chishizhi Wan （all the doses） down-regulated the protein level of LC3Ⅱ/Ⅰ （

P

<

0.05，

P

<

0.01）. Compared with those in the trimetazidine group， the serum AST level rose in the low-dose Wutou Chishizhi Wan group （

P

<

0.05） and declined in the high-dose group （

P

<

0.01）， and the protein level of Beclin-1 was down-regulated in the medium-dose group （

P

<

0.01）. Additionally， the trimetazidine group had higher protein level of LC3Ⅱ/Ⅰ than medium- and high-dose Wutou Chishizhi Wan groups （

P

<

0.05，

P

<

0.01）， higher protein level of PI3K than low-， medium-， and high-dose groups （

P

<

0.01）， lower protein level of p-Akt than low- and medium-dose groups （

P

<

0.01）， and higher p-GSK-3

β

protein level than the medium-dose group （

P

<

0.01）.

Conclusion

2

Different doses of Wutou Chishizhi Wan can ameliorate MIRI， and the high dose has the best effect. Wutou Chishizhi Wan can reduce the activity of myocardial injury markers AST， CK， cTnT， and MYO， and alleviate the pathological damage of myocardial tissue. It can down-regulate the protein levels of beclin-1， LC3Ⅱ/Ⅰ， and up-regulate those of PI3K， p-Akt， and p-GSK-3

β

. In summary， Wutou Chishizhi Wan may inhibit excessive autophagy and regulate the PI3K/Akt/GSK-3

β

signaling pathway to exert protective effect on MIRI rats.