MiR-21 regulates pulmonary hypertension in rats via TGF-Œ≤1/Smad2 signaling pathway
Authors: X-D Hou
K Yi
F Ding
P Zhang
X-K Wang
T You
X-G Liu
Journal: European Review for Medical and Pharmacological Sciences (2019)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: miR-21; pulmonary hypertension; TGF-Œ≤1; Smad2; rats
Affiliations: Department of Cardiovascular, Gansu Province Hospital, Lanzhou, China. .

Abstract:  Objective: To investigate the effects of micro ribonucleic acid (miR)-21 on pulmonary hypertension (PH) in rats via regulating tumor growth factor-Œ≤1 (TGF-Œ≤1)/mothers against decapentaplegic homolog 2 (Smad2) signaling pathway and the possible underlying mechanism. Materials and methods: MiR-21 inhibition vector (pLKO-anti-miR-21) was first constructed. The rat model of PH was established by hypoxia feeding induction. A total of three groups were established, including: blank control group, model group and miR-21 low-expression group were set up, with 12 rats in each group. The expression level of miR-21 in lung tissues of rats in each group was detected via quantitative polymerase chain reaction (qPCR). The right ventricle systolic pressure (RVSP) and right ventricular hypertrophy index (RVHI) of rats in each group were measured. The pathological changes in lung tissues of rats were detected using hematoxylin and eosin (H&amp;E) staining. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was used to detect the level of apoptosis in lung tissues of rats in each group. Furthermore, Western blotting was adopted to detect the expression levels of TGF-Œ≤1/Smad2 signal pathway-related proteins and apoptosis-related proteins in lung tissues of rats in each group. Results: Compared with blank control group, the expression level of miR-21 in lung tissues of rats in model group was significantly increased (p&lt;0.01). Meanwhile, miR-21 expression in lung tissues of rats in miR-21 low-expression group was significantly decreased by transfection of miR-21 inhibition vector (p&lt;0.01). The RVSP and RVHI of rats in model group were significantly higher than those of blank control group and miR-21 low-expression group (p&lt;0.01). H&amp;E staining results indicated that the degree of lung tissue injury in model group was remarkably higher than blank control group and miR-21 low-expression group (p&lt;0.01). According to TUNEL staining results, the number of apoptotic cells in lung tissues of rats in model group was markedly smaller than that of miR-21 low-expression group (p&lt;0.01). Moreover, the expression level of Caspase 3 in lung tissues of rats in model group was significantly lower than that of miR-21 low-expression group, while the expression level of B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein (BAX) was markedly higher. The expression levels of TGF-Œ≤1 and phosphorylated (p)-Smad2 in lung tissues of rats in model group were evidently higher than those of blank control group (p&lt;0.01). In addition, lowly expressed miR-21 could effectively reduce the expressions of TGF-Œ≤1 and p-Smad2 (p&lt;0.01). Conclusions: MiR-21 regulates the symptoms of PH in rats by activating TGF-Œ≤1/Smad2 signaling pathway. 

Retracted: Yes

PubPeer comments:
  Figure 4. Apoptosis level in lung tissues of rats in each group detected using TUNEL staining. There were no significant TUNEL-positive cells in lung tissues of rats in blank control group and model group. The number of TUNEL-positive cells in lung tissues of rats in miR-21 low-expression group was evidently larger than that of model group . Control and model groups are overlapping details of a larger image.  Lightened for visibility:  , 
 In other news, the  Control model image appears to be present as the Control of Fig 4 in [Li Wang (2019)] , while the  treatment image overlaps with that figure s  Model image.   No authors in common. , 
 #2 Another observation - Here comparing Fig 4 with Fig 3 of [Sun et al (2019)] .   , 
  Figure 5. Expression level of apoptotic proteins in lung tissues of rats in each group detected by Western blotting. Compare Blc-2 with (at left) Alk3, from Fig 6 of [Li Wang (2019)] .  , 
 The article u201cMiR-21 regulates pulmonary hypertension in rats via TGF-u03b21 Smad2 signaling pathway, by F. Ding, T. You, X.-D. Hou, K. Yi, X.-G. Liu, P. Zhang, X.-K. Wang, published in Eur Rev Med Pharmacol Sci 2019; 23 (9): 3984-3992u2013DOI: 10.26355 eurrev_201905_17828u2013PMID: 31115027u201d has been withdrawn from the authors. [The Publisher apologizes for any inconvenience this may cause] . ,