OBJECTIVE

2

To discuss the impact of Wenyang lishui formula on ventricular remodeling in rats with pulmonary hypertension-induced right heart failure （RHF） based on the Hippo/Yes-associated protein （YAP） signaling pathway.

METHODS

2

Ten rats were randomly selected as the control group. The remaining 63 rats were given a single intraperitoneal injection of monocrotaline to establish the pulmonary hypertension-induced RHF model. The 50 rats that successfully underwent the model establishment were randomly divided into the RHF group， low-dose group of Wenyang lishui formula （4.25 g/kg）， high-dose group of the Wenyang lishui formula （17.00 g/kg）， furosemide group （20 mg/kg）， and high-dose group of Wenyang lishui formula+Hippo/YAP signaling pathway activator group （17.00 g/kg of Wenyang lishui formula+16 mg/kg of PY-60）， with 10 rats in each group. The rats in each group were given the corresponding drug solution or normal saline by gavage or/and tail vein injection， once a day， for 4 consecutive weeks. During the experiment， the general conditions of the rats in each group were observed； after the last administration， the right ventricular diameter， right atrial diameter， end-diastolic volume， pulmonary artery blood flow acceleration time （PAAT） and its ratio to ejection time （ET） （PAAT/ET）， pulmonary artery pressure and its ratio to pulmonary arterial flow velocity （pulmonary artery pressure/velocity） were measured. The plasma levels of brain natriuretic peptide and angiotensin Ⅱ （AngⅡ） were detected. The pathological changes of the right ventricular tissue were observed， and the collagen volume fraction， the phosphorylation levels of the large tumor suppressor 1/2 （LATS1/2） and YAP， and the protein expression of the transcriptional coactivator of PDZ-binding motif （TAZ） were also detected.

RESULTS

2

Compared with the RHF group， the rats in Wenyang lishui formula low-dose and high-dose groups showed improved hair color， movement， diet， and mental state. The atrophy of right ventricular myocardial cells， the increase of inflammatory cells， collagen deposition， and hypertrophy of myocardial fibers were significantly alleviated. The right ventricular internal diameter， right atrial internal diameter， end-diastolic volume， pulmonary artery pressure， pulmonary artery pressure/velocity， the plasma levels of brain natriuretic peptide and AngⅡ， collagen volume fraction， the phosphorylation level of YAP and protein expression of TAZ were significantly decreased， while the PAAT， PAAT/ET and the phosphorylation level of LATS1/2 were significantly increased （

P

＜0.05）. PY-60 could significantly reverse the improvement effects of high-dose Wenyang lishui formula on the above quantitative indicators （

P

＜0.05）.

CONCLUSIONS

2

Wenyang lishui formula can restore the right heart function of pulmonary hypertension-induced RHF rats， reduce their pulmonary artery pressure， alleviate the pathological changes in their cardiac tissues， and the above effects may be related to the activation of Hippo expression and the inhibition of YAP phosphorylation.