OBJECTIVE

2

To explore the effects of Tianma xiongling zhixuan tablet on autophagy in vascular endothelial cells of rats and its potential mechanism.

METHODS

2

The rat aortic endothelial cells （RAECs） were divided into normal group， model group， blank serum group， traditional Chinese medicine （TCM） medicated serum group， autophagy blocker group， autophagy agonist group， and TCM combined with autophagy agonist group. Except for normal group， other groups were given 10 μg/mL lipopolysaccharide for 24 hours to induce RAECs inflammation injury model. Blank serum group was treated with 10% blank serum； TCM medicated serum group received 10% medicated serum derived from Tianma xiongling zhixuan tablet； autophagy blocker group was treated with 20 μmol/L of PD98059； autophagy agonist group was administered 50 μmol/L Honokiol. Lastly， the TCM combined with autophagy agonist group was given both 10% medicated serum derived from Tianma xiongling zhixuan tablet and 50 μmol/L Honokiol. The morphological characteristics of RAECs in each group were observed. The cell viability of each group， the contents of endothelin-1 （ET-1） and nitric oxide （NO）， mitochondrial reactive oxygen species， mitochondrial membrane potential， and the expression levels of PTEN-induced kinase 1 （PINK1）， Parkin， ubiquitin-binding protein （p62）， and microtubule-associated protein 1 light chain 3 （LC3） were detected.

RESULTS

2

Compared with model group， the levels of ET-1， mitochondrial reactive oxygen species， and the relative expressions of PINK1， Parkin， and LC3 proteins in the autophagy blocker group and TCM medicated serum group were decreased or down-regulated significantly （

P

＜0.05 or

P

＜0.01）； the cell viability rate （only autophagy blocker group）， NO level， mitochondrial membrane potential， and the relative expression level of p62 protein were increased or up-regulated significantly （

P

＜0.05 or

P

＜0.01）； the pathological damage of RAECs was significantly improved， the number of cells increased significantly， and the typical paving stone-like characteristics were restored. The levels of ET-1， mitochondrial reactive oxygen species， and the relative expression levels of Parkin and LC3 proteins in the autophagy agonist group were increased or up-regulated significantly （

P

＜0.05 or

P

＜0.01）， while cell viability rate was decreased significantly （

P

＜0.05）， the damage of RAECs was aggravated. Compared with the autophagy agonist group， the cell viability rate and the relative expression level of p62 protein in TCM combined autophagy agonist group were increased or up-regulated significantly （

P

＜0.05 or

P

＜0.01）， while the levels of ET-1， the relative expression levels of PINK1， Parkin， and LC3 proteins were down-regulated significantly （

P

＜0.01）， the damage of RAECs was reversed to a certain extent.

CONCLUSIONS

2

Tianma xiongling zhixuan tablet protects vascular endothelial function by regulating mitochondrial autophagy， the mechanism of which may be associated with the regulation of PINK1/Parkin signaling pathway and the inhibition of mitochondrial autophagy.