Effects of miR-21 on hypertensive rats through PTEN/PI3K/Akt/mTOR signaling pathway
Authors: W Xu
Y-J Shi
Y-F Han
J-X Li
Y-D Chen
L-L Niu
Journal: European review for medical and pharmacological sciences (2019)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: miR-21; hypertensive rats; PTEN; PI3K; Akt
Affiliations: Department of Cardiology, Chinese PLA General Hospital, Beijing, China. .

Abstract:  Objective: The aim of this study was to investigate the effects of micro-ribonucleic acid (miR)-21 on hypertensive rats through the phosphatase and tensin homolog deleted on chromosome ten (PTEN)/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway. Materials and methods: A total of 10 spontaneously hypertensive rats (SHRs) were selected as the model group. Meanwhile, 10 rats with the same age were enrolled in the normal control group. Real Time-fluorescence quantitative Polymerase Chain Reaction (qRT-PCR) was performed to detect the mRNA level of miR-21 in rats of the SHR model group and control group. The tail arterial diastolic pressure of rats in the awake and resting state was measured in both groups, respectively. Pathological sections were prepared to evaluate pathological changes in myocardial tissues. Subsequently, myocardial cells were isolated, cultured and transfected with miR-21 mimics and miR-21 inhibitor, respectively. Transfection efficiency was verified using fluorescence quantitative PCR. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay was utilized to determine the apoptosis level of myocardial cells. Furthermore, the expression levels of the signaling pathway-related proteins were detected via Western blotting assay. Results: Fluorescence quantitative PCR results revealed that the expression level of miR-21 was significantly higher in the SHR model group (p&lt;0.05). The diastolic pressure increased markedly in the SHR model group when compared with that in the control group (p&lt;0.05). Subsequent hematoxylin and eosin (HE) staining indicated apparent myocardial tissue injury in the SHR model group (p&lt;0.05). After transfection, the results showed that miR-21 inhibitor could effectively down-regulate the expression level of miR-21 in myocardial cells (p&lt;0.05). Meanwhile, TUNEL staining revealed that the number of apoptotic cells in the miR-21 inhibitor group was remarkably higher than that of the other two groups (p&lt;0.05). In addition, Western blotting results manifested that the protein expression levels of PTEN, PI3K, Akt and mTOR were significantly lower in the miR-21 mimics group (p&lt;0.05), whereas was remarkably higher in the miR-21 inhibitor group (p&lt;0.05). Conclusions: MiR-21 is involved in regulating the pathological symptoms and myocardial cell apoptosis in hypertensive rats through the PTEN/PI3K/Akt/mTOR signaling pathway. 

Retracted: No

PubPeer comments:
 Figure 3.  Pathological changes in myocardial tissues of rats in each group detected via HE staining . ![file] Please compare the SHR example with the MALAT1 example of Figure 2 from [Fan et al (2019)] :  HE staining of heart. A, MALAT1 group (u00d710). B, siMALAT1 group (u00d710). The myocardial cells are disorderly arranged and the muscle fibers are thickened in the MALAT1 group. In the siMALAT1 group, the myocardial injury almost cannot be observed . ![file] , 
 #1 Another sighting of Fig 3! Figure 3A from [Wang et al (2019)] .  HE staining results of rat heart. A, Model group (u00d710). B, Treatment group (u00d710). Disorderly-arranged myocardial cells and thickened muscle fibers are detected in the model group, while almost no myocardial injury is found in the treatment group. ![] , 
 #1 Fig 3 Control: ![] Fig 3A from [Zeng et al (2019)] :  HE staining of rat s heart. A, Sham group, B, AMI group, C, ATV-AMI group . ![] , 
 Figure 5.  Apoptosis level in myocardial tissues of rats in each group detected via TUNEL staining. A, TUNEL staining (magnification: 40u00d7). ![file] Despite different authorship, details of the Control panel overlap with the Control and ATO panels of Fig 4 [Zhu et al (2020)] . And by extension, with corresponding panels from numerous other papers. ![file] , 
 Because these papers all have at least one image in common, while not sharing any authors or affiliations, they appear to be produced by a paper mill, which might have supplied the papers and the figures. As of today, this set contains at least 9 papers, all connected to each other with at least one photo, as per the work of Hoya Camphorifolia. * H. Wang et al. - DOI: 10.26355 eurrev_201912_19695 - https: pubpeer.com publications 7BB185FB656F0F8214F92EDFE047FF * HT Zeng et al. - DOI: 10.26355 eurrev_201908_18757 - https: pubpeer.com publications B226E56465DACEA93791215756340B * MH Lun et al. - DOI: 10.26355 eurrev_202005_21366 - https: pubpeer.com publications AAA8F559D37A6D853CC16764A06A53 * Q Xu et al. - DOI: 10.26355 eurrev_201909_19026 - https: pubpeer.com publications C6F5DA3CA8F64BD57CE8A9B38616D0 * YJ Shi et al. - DOI: 10.26355 eurrev_201906_18082 - https: pubpeer.com publications 153695342827B732C15C614F61DF10 * YJ Wan et al. - DOI: 10.26355 eurrev_201908_18622 - https: pubpeer.com publications 41C0C61998A1A6C6339689A61A6ABF * YT Zhu et al. - DOI: 10.26355 eurrev_202005_21205 - https: pubpeer.com publications 277C24C645B71AF55A72A1200C46B4 * YY Wang et al. - DOI: 10.26355 eurrev_201912_19696 - https: pubpeer.com publications 702E90DEA6ED9278B2F67828C5329D * YZ Fan et al. - DOI: 10.26355 eurrev_201910_19306 - https: pubpeer.com publications 0B80BCE778E3D360504102D662CDE5 ,