Microarray analysis reveals a potential role of LncRNAs expression in cardiac cell proliferation

Background

Long non-coding RNAs (LncRNAs) have been identified to play important roles in epigenetic processes that underpin organogenesis. However, the role of LncRNAs in the regulation of transition from fetal to adult life of human heart has not been evaluated.

Methods

Immunofiuorescent staining was used to determine the extent of cardiac cell proliferation. Human LncRNA microarrays were applied to define gene expression signatures of the fetal (13–17 weeks of gestation, n?=?4) and adult hearts (30–40 years old, n?=?4). Pathway analysis was performed to predict the function of differentially expressed mRNAs (DEM). DEM related to cell proliferation were selected to construct a lncRNA-mRNA co-expression network. Eight lncRNAs were confirmed by quantificational real-time polymerase chain reaction (n?=?6).

Results

Cardiac cell proliferation was significant in the fetal heart. Two thousand six hundred six lncRNAs and 3079 mRNAs were found to be differentially expressed. Cell cycle was the most enriched pathway in down-regulated genes in the adult heart. Eight lncRNAs (RP11-119 F7.5, AX747860, HBBP1, LINC00304, TPTE2P6, AC034193.5, XLOC_006934 and AL833346) were predicted to play a central role in cardiac cell proliferation.

Conclusions

We discovered a profile of lncRNAs differentially expressed between the human fetal and adult heart. Several meaningful lncRNAs involved in cardiac cell proliferation were disclosed.

     

Expression profile of long non-coding RNAs during the differentiation of human umbilical cord derived mesenchymal stem cells into cardiomyocyte-like cells

We aimed to investigate the differentially expressed long non-coding RNAs (lncRNAs) during the differentiation of human umbilical cord derived mesenchymal stem cells (hUCMSCs) into cardiomyocyte-like cells induced by 5-aza. hUCMSCs were isolated and purified from umbilical cords. After treated with 10 μmol/L 5-Aza for 24 h, hUCMSCs wereas continued to be cultured for 14 days. Comparison of cardiac specific genes and the expression profile of lncRNAs on hUCMSCs between day 14 and day 0 was performed using immunofluorescence staining, immunohistochemistry, Western blot assay, RT-PCR and lncRNA microarray. Results show that well-organized sarcomeric structure and more cTnI and MLC2a staining were seen in hUCMSCs of day 14 after 5-aza-induced compared to those in day 0. Expression of Desmin, Nkx2.5, cTnI and MLC2a of hUCMSCs was much higher on day 14 compared with day 0 (P?<?0.01). 41 differentially expressed lncRNAs were found on day 14 hUCMSCs compared those of day 0 were identified. Among them, 25 upregulated and 16 downregulated. Four out of the five upregulated lncRNAs (P?=?0.00035, 0.014, 0.016 and 0.005 for uc010vei.1, X72487, BC064139, AK092074) and four out of the five downregulated lncRNAs (P?=?0.038, 0.0014, 0.00026 and 0.004 for X85157, uc007keu.1, AK309872, NR_029399) showed significantly different expressions in further validation using RT-PCR. Our results illustrated that there was a dysregulation of the lncRNA profile during the differentiation of hUCMSCs into cardiomyocyte-like cells, which will provide the foundation for further study of the biological functions and mechanism of lncRNAs in the differentiation of hUCMSCs into cardiomyocyte-like cells.