To investigate the effects of RVD1 on autophagy and apoptosis of aging rat cardiomyocytes based on MAMs
10.19405/j.cnki.issn1000-1492.2023.11.015
- Author:
Yang Zheng
1
;
Yubing Huang
1
;
Wenxia Huang
1
;
Haitao Li
1
Author Information
1. Dept of Cardiovascular Medicine , Hainan Provincial People ′s Hospital , Haikou 570311
- Publication Type:Journal Article
- Keywords:
aging;
ResolvinD1;
mitochondria⁃associated endoplasmic reticulum membranes;
cardiomyocytes;
au⁃ tophagy;
apoptosis
- From:
Acta Universitatis Medicinalis Anhui
2023;58(11):1890-1897
- CountryChina
- Language:Chinese
-
Abstract:
Objective :To explore the regulatory effects of ResolvinD1 (RVD1) on autophagy and apoptosis of cardiomyocytes in aging rats , and the effects of RVD1 on mitochondria⁃associated endoplasmic reticulum membranes (MAMs) of myocardial tissue .
Methods :Thirty 18⁃month⁃old SD rats were randomly divided into model group , low⁃dose RVD1 group and high⁃dose RVD1 group , with 10 rats in each group , and another 10 6 ⁃month⁃old SD rats were selected as control group . The low⁃dose RVD1 group and high⁃dose RVD1 group were injected with 50 ng/ml and 100 ng/ml RVD1 through the tail vein , respectively , control group and model group were injected with the same amount of phosphate buffered saline (PBS) for 21 days . The β ⁃galactosidase activity of rat myocardial tissue was determined by p ⁃nitrophenol method , the histopathological changes of rat myocardial tissue were detected by hematoxylin⁃eosin (HE) staining , and the collagen deposition in rat myocardial tissue was observed by Masson staining , apoptosis of rat myocardial cells was detected by dUTP in situ end labeling mediated by terminal deoxynucleotide transferase(TUNEL) , the expression of autophagy marker microtubule⁃associated protein 3 (LC3) was detecotide transferase(TUNEL) , the expression of autophagy marker microtubule⁃associated protein 3 (LC3) was detected by immunohistochemical S ⁃P method , the ratio of LC3 ⁃ Ⅱ/LC3 ⁃ Ⅰ and the expression of Beclin⁃1 , p62 in rat myocardial tissue were determined by Western blot , the structure of MAMs in rat myocardial tissue was observed by transmission electron microscopy , the expression levels of glucose⁃regulatory protein 75 (GRP75) , volt⁃dependent anion channel 1 (VDAC1) and mitochondrial fusion protein 2 (Mfn2) in rat myocardial tissue were determined by Western blot .
Results :Compared with model group , β ⁃galactosidase activity of myocardial tissue decreased in low⁃dose RVD1 group and high⁃dose RVD1 group (P < 0. 05) , myocardial fiber breakage and myocardial cell damag were significantly alleviated , collagen fiber deposition was significantly reduced , and the proportion of TUNEL positive cells in myocardial tissue decreased (P < 0. 05) , the positive rate of LC3 protein increased (P < 0. 05) , the ratio of LC3 ⁃ Ⅱ/LC3 ⁃ Ⅰ increased , the relative expression level of Beclin⁃1 protein was up⁃regulated and the relative expression level of p62 protein was down⁃regulated ( P < 0. 05) , the structure of MAMs was tighter , and the percentage of MAMs in mitochondrial circumference also increased (P < 0. 05) , the relative protein expressions of GRP75 , VDAC1 and Mfn2 were up⁃regulated (P < 0. 05) . Compared with low⁃dose RVD1 group , β ⁃galactosidase activity in high⁃dose RVD1 group further decreased ( P < 0. 05) , no obvious damage was observed in myocardial tissue , collagen fiber deposition was further decreased , the proportion of TUNEL positive cells in myocardial tissue decreased (P < 0. 05 ) , and the positive rate of LC3 protein increased ( P < 0. 05 ) , LC3 ⁃ Ⅱ/LC3 ⁃ Ⅰ ratio increased , Beclin⁃1 relative expression level was up⁃regulated and p62 relative expression level was down⁃regulated (P < 0. 05) , the structure of MAMs was more compact , and their percentage in mitochondrial circumference further increased (P < 0. 05 ) , the relative expressions of GRP75 , VDAC1 and Mfn2 were further up⁃regulated ( P <0. 05) .
Conclusion :RVD1 can activate autophagy , alleviate myocardial apoptosis and collagen fiber deposition, and promote mitochondria⁃associated endoplasmic reticulum membranes in aging rats .
- Full text:2024071017374015899基于MAMs探究RVD1对...鼠心肌细胞自噬与凋亡的影响_郑扬.pdf
