Exosomal miR-320d derived from adipose tissue-derived MSCs inhibits apoptosis in cardiomyocytes with atrial fibrillation (AF)
Authors: Xiaohong Li
Haoran Zhang
Lina Liu
Hongyu Mao
Yamin Hu
Journal: Artificial Cells Nanomedicine and Biotechnology (2019)
Discipline: BIOLOGY & BIOCHEMISTRY
Keywords: Atrial fibrillation; STAT3; exosome; mesenchymal stem cells; miR-320d.
Affiliations: Department of Cardiovascular Medicine, Cangzhou Central Hospital, Cangzhou, China;, Nephrology Department, Cangzhou Central Hospital, Cangzhou, China

Abstract:  MicroRNAs (miRNAs) play a key role in various pathological processes like atrial fibrillation (AF), which is a common cardiac arrhythmia. Exosomes are essential information carrier in the intercellular communication. Therefore, this study aimed to investigate the effects of exosomal miR-320d on cardiomyocytes with AF and related mechanisms. To do this, AMSCs were transfected with miR-320d mimics, AMSCs-derived exosomes were co-cultured with cardiomyocytes with AF. MTT, TUNEL staining, flow cytometry, real-time PCR, western blots, and luciferase reporter assays were performed. The results revealed that miR-320d expression was decreased in AF cardiomyocytes. AF increased apoptosis and reduced cell viability in cardiomyocytes. By transfection with miR-320d mimics, the miR-320d level was increased in AMSCs, exosomes and cardiomyocytes, which reversed the effect of AF on cardiomyocytes. STAT3 was down-regulated in AF cardiomyocytes and was a direct target gene of miR-320d. Inhibition of STAT3 abolished the effect of modified exosomes in cardiomyocytes, causing decreased apoptosis and increased cell viability. Taken together, the results suggested that exosomal miR-320d was associated with AF cardiomyocytes apoptosis and cell viability and that the effect of miR-320d on cardiomyocytes is STAT3-dependent. Therefore, this study provides a novel understanding of the molecular basis of AF and provides insight into therapeutic strategies for AF. 

Retracted: No

PubPeer comments:
 In figure 1A and D a Western immunoblot has been reused and presented as something else. The anti-CD63 blot in Figure 1D shows a straight band without smearing. CD63, due to high glycosylation, gives a smeared appearance when detected by Western immunoblotting. ![file] , 
 Same figure, some other potential issues. ![file] *** False color ![file] , 
 Expression of Concern, [3 February 2022] . ------------------------- We, the Publisher and Editor of Artificial Cells, Nanomedicine, and Biotechnology, are issuing an Expression of Concern for the following article: After publication of this article, questions about the scientific integrity of the article content were brought to the Publisher and Editoru2019s attention. We reached out to the authors requesting that they supply information that would confirm the articleu2019s integrity. The authors could not respond in a timely manner to our requests to provide the original data. In particular, they were unable to provide full western blots, where the molecular weight markers are indicated. Therefore, as we continue to work through the issues raised, we advise readers to interpret the information presented in the article with due caution. The authors have been notified about this Expression of Concern. , 
 These authors have published very few papers between all of them and are affiliated with Cangzhou Central Hospital. The corresponding author s email address (taoshengn59@163.com) does not seem to resemble that author s name (Yamin Hu). These items taken together with the inability of the authors to provide the original data of a 3 year old paper, suggests the possibility that this paper was outsourced to a third party. ,