ABSTRACT
Objective:To observe the effect of Qiyu Sanlong decoction （QYSL） on the expressions of key molecules in signal axis of mammalian rapamycin target protein （mTOR）/yeast Atg6 homologous （Beclin1）/ microtubule-associated protein1 light chain3 （LC3） in A549 cells. Method:With A549 cells as the research object， the effect of QYSL medicated serum on cell viability of A549 cells were detected by cell counting kit-8 （CCK-8） method. The effect of QYSL decoction on A549 cell apoptosis， autophagosome formation and the expression of autophagy markers were detected by Terminal-deoxynucleoitidyl transferase mediated nick end labeling （TUNEL） method， transmission electron microscope （TEM）， Real-time polymerase chain reaction （Real-time PCR） and Western blot. Result:QYSL medicated serum could inhibit the viability of A549 cells in a concentration-dependent manner. Compared with the blank serum group， the number of apoptotic A549 cells in the QYSL medicated serum group was significantly increased （P<0.01）， and the formation of autophagosome was significantly increased. Compared with the blank serum group， the mRNA and protein expressions of mTOR in A549 cells in the QYSL serum group were significantly decreased （P<0.01）， while mRNA and protein expressions of Beclin-1， autophagy related genes 5 （ATG5）， autophagy related genes 13 （ATG13） were significantly increased （P<0.01）. Conclusion:QYSL decoction can induce autophagy in A549 cells， and its specific mechanism may be related to the down-regulation of mTOR expression， the up-regulation of Beclin1， ATG5， ATG13 and LC3 expression， and the promotion of LC3Ⅰ conversion to LC3Ⅱ.
ABSTRACT
Objective:Through phosphatidylinositol 3-kinase（PI3K）/protein kinase B （Akt）/mammalian rapamycin target protein （mTOR） signaling pathway， explore the effect of Zhigancao Tang on myocardial ischemia-reperfusion injury（MIRI）The role and mechanism of arrhythmia（ventricular tachycardia and ventricular fibrillation）. Method:The 72 SD rats were randomly divided into sham operation group，model group， Zhigancao Tang low，medium and high dose group（11.43，22.86，45.72 g·kg-1），Wenxin granule group（2.43 g·kg-1），continuous drug intervention for 10 days. Two hours after the last administration，the MIRI model of rat was prepared by ligating the left anterior descending coronary artery，and the changes of electrocardiogram were recorded. After successful modeling，blood and heart tissue were collected to detect the content of creatine creatine（CK），lactate dehydrogenase（LDH）and aspartate aminotransferase（AST）in the serum, the enzyme-linked immunoassay（ELISA） method was used to detect cardiac troponin（CtnI）content, immunohistochemical detection of myocardial PI3K，Akt，mTOR expression. Western blot was used to detect the myocardial autophagy-related protein microtubule-associated protein 1 light chain 3（LC-3），autophagy markers Beclin1 and PI3K/Akt/mTOR signaling pathway related protein expression and phosphorylated p-PI3K，p-Akt，p-mTOR levels. Result:In model group， 100% of ventricular tachycardia and 91.67% of ventricular fibrillation occurred. Compared with sham operation group， the serum levels of CK，LDH，AST，and CtnI in the model group were significantly increased（P<0.01），PI3K，Akt，mTOR AOD values in myocardial tissue were significantly increased （P<0.01），the relative expression of the ratio of LC3-Ⅱ/LC3-Ⅰ and Beclin1 was significantly increased（P<0.01），p-PI3K/PI3K，p-Akt/Akt，and p-mTOR/mTOR were significantly reduced （P<0.01）. Compared with model group， the incidence of ventricular tachycardia and ventricular fibrillation in the high-dose Zhigancao Tang group was significantly reduced （P<0.01），and the duration was the shortest compared with other administration groups（P<0.01）， CK，LDH，AST level and CtnI content were significantly reduced（P<0.01）， the expression of PI3K，Akt and mTOR of Zhigancao Tang group was significantly decreased with increasing dose（P<0.01）， the expression of LC-3 and Beclin1 was accompanied by Zhigancao Tang increase of each dose group of soup had different degrees of decrease （P<0.01），while the expression ratio of PI3K/Akt/mTOR-related protein was significantly increased （P<0.05，P<0.01）. Conclusion:Pretreatment of Zhigancao Tang can reduce the abusually elevated cardiac enzymes CK, LDH, AST and CtnI, inhibit excessive autophagy of cells, and up-regulate the expression of PI3K, Akt and mTOR, indicating that the anti-MIRI arrhythmia effect of Zhigancao Tang may be related to the PI3K/Akt/mTOR signaling pathway.