ABSTRACT
It is not fully clear why there is a higher contribution of pluripotent stem cells (PSCs) to the chimera produced by injection of PSCs into 4-cell or 8-cell stage embryos compared with blastocyst injection. Here, we show that not only embryonic stem cells (ESCs) but also induced pluripotent stem cells (iPSCs) can generate F0 nearly 100% donor cell-derived mice by 4-cell stage embryo injection, and the approach has a "dose effect". Through an analysis of the PSC-secreted proteins, Activin A was found to impede epiblast (EPI) lineage development while promoting trophectoderm (TE) differentiation, resulting in replacement of the EPI lineage of host embryos with PSCs. Interestingly, the injection of ESCs into blastocysts cultured with Activin A (cultured from 4-cell stage to early blastocyst at E3.5) could increase the contribution of ESCs to the chimera. The results indicated that PSCs secrete protein Activin A to improve their EPI competency after injection into recipient embryos through influencing the development of mouse early embryos. This result is useful for optimizing the chimera production system and for a deep understanding of PSCs effects on early embryo development.
Subject(s)
Animals , Mice , Activins , Metabolism , Cells, Cultured , Embryonic Development , Germ Layers , Metabolism , Pluripotent Stem Cells , Cell Biology , MetabolismABSTRACT
We developed a universal probe based microRNA detection assay and applied it to detect microRNA-146a in human brucellosis,testing the possibility of using it as diagnosis signature.By using orthogonal design,the annealing temperature,probe concentration and commercial kits were optimized and the assay was developed.Total RNAs were isolated from plasma of human brucellosis and healthy control,and microRNA-146a was detected and compared.Results reveal that the optimized universal probe assay was established,which was more specific than the SYBR GreenI assay,and had a wider range of amplification.Compared with healthy control,the application of universal probe assay for the detection of serum microRNA146a in patients with brucellosis was significantly inhibited (P＜0.01).Implying the potential of microRNA-146a as biomarker in diagnosis of brucellosis.It is suggested that universal probe based assay is a universal,specific and sensitive method for microRNA detection.MicroRNA-146a represents a potential biomarker for human brucellosis diagnosis.
ABSTRACT
Objective: To study the relationship between myocardial X-box binding protein 1 (XBP1) expression and myocardial apoptosis in experimental diabetic cardiomyopathy (DCM) rat’s model and to clarify the mechanism of valsartan inhibiting myocardial apoptosis. Methods: A total of 50 Wistar rats were divided into 2 groups: Control group, the rats received intraperitoneal citrate buffer at 65mg/kg,n=10 and Streptozotocin group, the rats received intraperitoneal streptozotocin at 65mg/kg,n=40, all animals were treated for 7 days. DCM model was established in 37 rats (fasting blood glucose ≥ 16.7mmole/L) and they were further divided into 2 groups: DCM group, the rats received intragastric normal saline,n=20 and DCM + valsartan group, the rats received intragastric valsartan at 30mg/kg·day,n=17. The rats were treated for 16 weeks. The body weight, tail blood pressure, glucose and cardiac function were compared among 3 groups. Myocardial apoptosis was detected by TUNEL staining, RNA and protein expressions of myocardial cytochrome C, cleaved caspase 3, glucose regulation protein 78 (GRP78) and XBP1-s were examined by immunolfuorescence, real time RT-PCR and Western blot analysis. Results: Compared with Control group, DCM group showed disordered cardiac structure, more collagen content and myocardial apoptosis,P<0.05; increased RNA and protein expressions of GRP78, XBP1-s, cleaved caspase 3 and cytochrome C,P<0.05. Compared with DCM group, DCM + valsartan group had rather regularly arranged myocardiocytes, less interstitial ifbrosis and myocardial apoptosis,P<0.05; decreased RNA and protein expressions of GRP78, XBP1-s, cleaved caspase 3 and cytochrome C,P<0.05. Conclusion: Valsartan may inhibit myocardial XBP1 activation and therefore, reduce the myocardial apoptosis in experimental DCM rat’s model.