MicroRNAs (miRNAs) are small non-coding RNA molecules that participate in transcriptional and post-transcriptional regulation of gene expression. miRNAs have numerous roles in cellular function including embryonic development. Human embryonic stem cells (hESCs) are capable of self-renewal and can differentiate into most of cell types including cardiomyocytes (CMs). These characteristics of hESCs make them considered as an important model for studying human embryonic development and tissue specific differentiation. In this study, we tried to demonstrate the profile of miRNA expression in cardiac differentiation from hESCs. To induce differentiation, we differentiated hESCs into CMs by direct differentiation method and characterized differentiated cells. To analyze the expression of miRNAs, we distinguished (days 4, 8, 12, 16, 20, 24, 28) and isolated RNAs from each differentiation stage. miRNA specific RT-qPCR was performed and the expression profile of miR-1, -30d, -133a, -143, -145, -378a, -499a was evaluated. The expression of all miRs was up-regulated at day 8. miR-143 and -145 expression was also up-regulated at the later stage of differentiation. Only miR-378a expression returned to undifferentiated hESC levels at the other stages of differentiation. In conclusion, we elucidated the expression profile of miRNAs during differentiation into cardiomyocytes from hESCs. Our findings demonstrate the expression of miRNAs was stage-dependent during differentiation and suggest that the differentiation into CMs can be regulated by miRNAs through direct or indirect pathway.
Embryonic Development ; Female ; Gene Expression Regulation ; Human Embryonic Stem Cells ; Humans* ; Methods ; MicroRNAs* ; Myocytes, Cardiac ; Pregnancy ; RNA ; RNA, Small Untranslated

Objective To investigate the clinical efficacy of low-frequency transcranial magnetic stimulation (rTMS) on post-stroke upper limb spasticity and its mechanism. Methods From September, 2015 to December, 2017, 23 patients with post-stroke upper limb paralysis were randomly divided into control group (n=13) and experimental group (n=10). Both groups received routine rehabilitation, and the experimental group received 1 Hz rTMS at primary motor area (M1) for eight weeks. They were assessed with modified Ashworth Scale (MAS), modified Barthel Index (MBI) and Fugl-Meyer Assessment-Upper Extremities (FMA-UE) before and after treatment, while the activation under fMRI in the task state was observed and the laterality index (LI) was calculated. Results The scores of MAS, FMA-UE and MBI improved after treatment in both groups (Z>2.121, t=6.248, P<0.05), and improved more in the experimental group than in the control group (Z>2.084, t=-2.095, P<0.05). The ipsilateral M1, ipsilateral sensory motor cortex and bilateral supplementary motor area were activated more in the control group than in the experimental group during the movement of affected hand. LI in the M1 increased after treatment in both groups (Z>2.366, P<0.05), and was more in the experimental group than in the control group (Z=-2.430, P<0.05). There was a positive correlation between the change of LI in the M1 and the improvement of the MAS and FMA-UE (r>0.612, P<0.05). Conclusion Low-frequency rTMS may improve the motor function and spasticity of upper limb after stroke by promoting reorganization of the cortex and inducing normalization of cortical function.