原代心肌细胞 z-bio 2021-04-21 469

　　Objective To explore the role of miR-199a in primary rat cardiomyocytes induced by LPS.

　　Method The primary rat cardiomyocytes were divided into control group (NC), LPS group, LPS+miR-199a mimic group, and LPS+miR-199a inhibitor group. In this experiment, the CCK8 method was used to explore the effect of miR-199a on the cell viability of rat primary myocardium. Subsequently, ELISA was used to detect the release of miR-199a on LPS-induced inflammatory factors such as TNF-α and IL-1β in primary rat cardiomyocytes. Flow cytometry was used to detect the apoptotic protein changes of miR-199a for LPS-induced primary rat cardiomyocytes. Western blot experiments were used to study the expression of miR-199a of miR-199a mimics or inhibitors and the expression of p-p65, p65 and p-iκBa, iκBa and apoptotic proteins in primary rat cardiomyocytes induced by LPS by miR-199a Happening.

　　Results The CCK8 method found that compared with the NC group, LPS inhibited the viability of rat primary myocardial cells (P<0.01). However, after treatment with the simulant, the primary myocardial viability induced by LPS was more severely inhibited. (P<0. 05). At the same time, compared with the mimic group, the primary cardiomyocyte viability of rats in the miR-199a inhibitor group was inhibited and decreased (P<0.01). ELISA results showed that compared with NC group, LPS induced the release of TNF-α and IL-1β (P<0.05). Compared with the LPS group, the miR-199a mimic group aggravated the release of TNF-α (P<0.01) and IL-1β (P<0.05), while the miR-199a inhibitor group TNF-α (P<0.01) <0.01) and IL-1β (P<0.05) release decreased. The results of flow cytometry and Western blot showed that the miR-199a mimic at 50 nmol/L can aggravate the apoptosis of primary rat cardiomyocytes induced by LPS by up-regulating the expression of caspase3 and bax and down-regulating the expression of bcl2 (P<0. 05). Further testing of the NF-κΒ pathway found that LPS can activate the NF-κΒ pathway of primary rat cardiomyocytes through the up-regulation of p-iκBa and p-p65 expression. The up-regulation of p-iκBa is more obvious. At the same time, after blocking miR-199a, the expression of p-p65 and p-iκBa was down-regulated compared with the mimic group. These findings indicate that treatment with mimetics can aggravate the activation of the NF-κB signaling pathway in LPS-induced myocarditis in vivo. Further use of NF-κB pathway inhibitors found that miR-199a mimics could not aggravate the inhibition of LPS on the viability of primary rat cardiomyocytes, which further suggests that miR-199a may aggravate cardiomyocyte damage through the NF-κB pathway.

　　Conclusion miR-199a can aggravate the damage of cardiomyocytes. This damage is mainly achieved through the NF-κB signaling pathway.