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Background/Aims: The aim of this study was to assess the association between circulating cell-derived microparticles (MPs) and type 2 diabetes mellitus (T2DM). Methods: A literature search was performed systematically in PubMed and Embase to identify available case-control or cross-sectional studies that compared different types of cell-derived MPs in patients with T2DM and non-diabetic controls. Pooled standardized mean differences (SMDs) of each MP type were pooled using meta-analysis. Results: Forty-eight studies involving 2,460 patients with T2DM and 1,880 non-diabetic controls were included for systematic review and 34 of which were included for quantitative study by meta-analysis. In the overall analysis, the levels of circulating total MPs (TMPs), platelet-derived MPs (PMPs), monocyte-derived MPs (MMPs) and endothelium-derived MPs (EMPs) were significantly higher in T2DM patients than those in controls (TMPs: SMD, 0.64; 95%CI, 0.12~1.15; P=0.02; PMPs: SMD, 1.19; 95%CI, 0.88~1.50; P <0.00001; MMPs: SMD, 0.92; 95%CI, 0.66~1.17; P <0.00001; EMPs: SMD, 0.73; 95%CI, 0.50~0.96; P <0.00001). Meanwhile, no significant difference was shown in leukocyte-derived MPs (LMPs) level between diabetic and non-diabetic groups (SMD, 0.37; 95%CI, -0.15~0.89; P=0.17). Conclusions: The counts of TMPs, PMPs, MMPs and EMPs elevated in patients with T2DM. And cell-derived MPs may play a role in the pathogenesis of T2DM. [ABSTRACT FROM AUTHOR]

Inflammatory mediators, many of which activate the signaling of nuclear factor kappa B (NFκB), have received increasing attention in the field of neurogenesis. NFκB signaling regulates neurite outgrowth and neural plasticity as well as the proliferation/apoptosis and terminal differentiation of neural stem cells (NSCs). Early neurogenesis from NSCs produces identical progeny through symmetric division and committed daughter cells through asymmetric division. Here, we show that NFκB signaling is required for NSC initial differentiation. The canonical IKKβ/IκBα/p65 pathway is activated during the initial stages of neural differentiation induced by treatment with TNFα or withdrawal of epidermal growth factor/basic fibroblast growth factor. NSC-specific inhibition of NFκB in transgenic mice causes an accumulation of Nestin+/Sox2+/glial fibrillary acidic protein+ NSCs. Inhibition of NFκB signaling in vitro blocks differentiation and asymmetric division and maintains NSCs in an undifferentiated state. The induction of initial differentiation and asymmetry by NFκB signaling occurs through the inhibition of C/EBPβ expression. Our data reveal a novel function of NFκB signaling in early neurogenesis and provide insight into the molecular mechanisms underlying neurodevelopmental disorders and neurodegenerative diseases. S TEM C ELLS 2012;30:510-524 [ABSTRACT FROM AUTHOR]

C/EBPβ is an intrinsically repressed transcription factor that regulates genes involved in differentiation, proliferation, tumorigenesis, and apoptosis. C/EBPβ acts as a repressor that is turned into an activator by the Ras oncoprotein through phosphorylation of a MAPK site. C/EBPβ activation is accompanied by a conformational change. Active and repressive C/EBPβ interacts with multisubunit Mediator complexes through the CRSP130/Sur2 subunit. The CRSP130/Sur2 subunit is common to two distinct types of Mediator complexes, characterized by CRSP70 and CDK8 proteins as transcriptionally active and inactive Mediator, respectively. Knockdown of CRSP130/Sur2 prevents Mediator binding and transactivation through C/EBPβ. Oncogenic Ras signaling or activating mutations in C/EBPβ selects the transcriptionally active Mediator complex that also associates with RNA polymerase II. These results show that a Ras-induced structural alteration of C/EBPβ determines differential gene activation through selective interaction with distinct Mediator complexes. [Copyright &y& Elsevier]

Abstract: Apoptosis of vascular smooth muscle cell (VSMC) is one of the major pathologic features in atherosclerosis. The platelet-derived growth factor (PDGF) pathway has been shown to provide survival signals in VSMCs and PDGF receptors are also highly expressed in VSMCs contained in the plaques of atherosclerosis. However, the downstream targets of PDGF signaling are unclear. In the current study, we show that PDGF signals stimulate the protein expression of c-Myb in human arterial VSMCs. Inhibition of c-Myb function in VSMCs enhanced apoptosis in PDGF treated VSMCs. Our data suggest that c-Myb functions as a downstream target of the PDGF survival pathway and suggest that c-Myb plays an essential role in adult VSMC survival. [Copyright &y& Elsevier]