Establishment and characterization of an immortalized epicardial cell line

EZH2 controls epicardial cell migration during heart development

Enhancer of zeste homolog 2 (EZH2) is an important transcriptional regulator in development that catalyzes H3K27me3. The role of EZH2 in epicardial development is still unknown. In this study, we show that EZH2 is expressed in epicardial cells during both human and mouse heart development. Ezh2 epicardial deletion resulted in impaired epicardial cell migration, myocardial hypoplasia, and defective coronary plexus development, leading to embryonic lethality. By using RNA sequencing, we identified that EZH2 controls the transcription of tissue inhibitor of metalloproteinase 3 (TIMP3) in epicardial cells during heart development. Loss-of-function studies revealed that EZH2 promotes epicardial cell migration by suppressing TIMP3 expression. We also found that epicardial Ezh2 deficiency-induced TIMP3 up-regulation leads to extracellular matrix reconstruction in the embryonic myocardium by mass spectrometry. In conclusion, our results demonstrate that EZH2 is required for epicardial cell migration because it blocks Timp3 transcription, which is vital for heart development. Our study provides new insight into the function of EZH2 in cell migration and epicardial development.

Protective Effect of Resveratrol on Immortalized Duck Intestinal Epithelial Cells Exposed to H2O2

Resveratrol is a polyphenolic compound with anti-oxidation effects. The mechanisms underlying the antioxidant effects of resveratrol in duck intestinal epithelial cells remain unclear. The protective effects of resveratrol against oxidative stress induced by H2O2 on immortalized duck intestinal epithelial cells (IDECs) were investigated. IDECs were established by transferring the lentivirus-mediated simian virus 40 large T (SV40T) gene into small intestinal epithelial cells derived from duck embryos. IDECs were morphologically indistinguishable from the primary intestinal epithelial cells. The marker protein cytokeratin 18 (CK18) was also detected in the cultured cells. We found that resveratrol significantly increased the cell viability and activity of catalase and decreased the level of intracellular reactive oxygen species and malondialdehyde, as well as the apoptosis rate induced by H2O2 (p < 0.05). Resveratrol up-regulated the expression of NRF2, p-NRF2, p-AKT, and p-P38 proteins and decreased the levels of cleaved caspase-3 and cleaved caspase-9 and the ratio of Bax to Bcl-2 in H2O2-induced IDECs (p < 0.05). Our findings revealed that resveratrol might alleviate oxidative stress by the PI3K/AKT and P38 MAPK signal pathways and inhibit apoptosis by altering the levels of cleaved caspase-3, cleaved caspase-9, Bax, and Bcl-2 in IDECs exposed to H2O2.

Establishment and characterization of an immortalized epicardial cell line

Recently, the increasing significance of the epicardium in cardiac development and regeneration is beginning to be recognized. However, because of the small proportion of primary epicardial cells and the limited cell culture time, further research on the mechanism of epicardial cells is hindered. Here, we transfected simian virus 40 Large T (SV40-LT) into primary epicardial cells to establish an immortalized cell line, named EpiSV40. We further demonstrated that EpiSV40 can be easy to culture and has the proliferation, migration and differentiation capacities comparable to primary epicardial cells. EpiSV40 can serve as an ideal in vitro model for epicardial cell research, which will booster the study of the epicardium in cardiac development and heart regeneration.