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author:("Liu, panying")
1.  The proteasome function reporter GFPu accumulates in young brains of the APPswe/PS1dE9 Alzheimer’s disease mouse model 
Alzheimer’s disease (AD), the most common cause of dementia, is neuropathologically characterized by accumulation of insoluble fibrous inclusions in the brain in the form of intracellular neurofibrillary tangles and extracellular senile plaques. Perturbation of the ubiquitin-proteasome system (UPS) has long been considered an attractive hypothesis to explain the pathogenesis of AD. However, studies on UPS functionality with various methods and AD models have achieved non-conclusive results. To get further insight into UPS functionality in AD, we have crossed a well-documented APPswe/PS1dE9 AD mouse model with a UPS functionality reporter, GFPu, mouse expressing green fluorescence protein (GFP) fused to a constitutive degradation signal (CL-1) that facilitates its rapid turnover in conditions of a normal UPS. Our western blot results indicate that GFPu reporter protein was accumulated in the cortex and hippocampus but not striatum in the APPswe/PS1dE9 AD mouse model at 4 weeks of age, which is confirmed by fluorescence microscopy and elevated levels of p53, an endogenous UPS substrate. In accordance with this, the levels of ubiquitinated proteins were elevated in the AD mouse model. These results suggest that UPS is either impaired or functionally insufficient in specific brain regions in the APPswe/PS1dE9 AD mouse model at a very young age, long before senile plaque formation and the onset of memory loss. These observations may shed new light on the pathogenesis of AD.
doi:10.1007/s10571-013-0022-9
PMCID: PMC3954921  PMID: 24363091
Alzheimer disease; ubiquitin-proteasome system; proteasome function reporter; GFPu; protein degradation; ubiquitinated proteins
2.  Upregulated MicroRNA-155 Expression in Peripheral Blood Mononuclear Cells and Fibroblast-Like Synoviocytes in Rheumatoid Arthritis 
Objective. This study was to screen for the miRNAs differently expressed in peripheral blood mononuclear cells (PBMC) of RA, to further identify the expression of miR-155 in RA PBMC and fibroblast-like synoviocytes (FLS), and to evaluate the function of miR-155 in RA-FLS. Methods. Microarray was used to screen for differentially expressed miRNAs in RA PBMC. miR-155 expression in PBMC and FLS of RA were identified by real-time PCR. Enforced overexpression and downexpression of miR-155 were used to investigate the function of miR-155 in RA-FLS. Expression of IKBKE which was previously identified as the actual target of miR-155 was examined by Western blot and real-time PCR in RA-FLS. Results. miR-155 levels were increased in both PBMC and FLS of RA and could be induced by TNF-α. Upregulation of miR-155 decreased MMP-3 levels and suppressed proliferation and invasion of RA-FLS. Inverse relationship between the expressions of miR-155 and the MMPs production-related protein IKBKE was found. Conclusion. An inflammatory milieu may alter miRNA expression profiles in rheumatoid arthritis. miR-155 is upregulated in RA-FLS, and it may be a protective factor against the inflammatory effect in part by attenuating expression of IKBKE.
doi:10.1155/2013/296139
PMCID: PMC3789322  PMID: 24151514
3.  Therapeutic potential of human umbilical cord mesenchymal stem cells in the treatment of rheumatoid arthritis 
Arthritis Research & Therapy  2010;12(6):R210.
Introduction
Rheumatoid arthritis (RA) is a T-cell-mediated systemic autoimmune disease, characterized by synovium inflammation and articular destruction. Bone marrow mesenchymal stem cells (MSCs) could be effective in the treatment of several autoimmune diseases. However, there has been thus far no report on umbilical cord (UC)-MSCs in the treatment of RA. Here, potential immunosuppressive effects of human UC-MSCs in RA were evaluated.
Methods
The effects of UC-MSCs on the responses of fibroblast-like synoviocytes (FLSs) and T cells in RA patients were explored. The possible molecular mechanism mediating this immunosuppressive effect of UC-MSCs was explored by addition of inhibitors to indoleamine 2,3-dioxygenase (IDO), Nitric oxide (NO), prostaglandin E2 (PGE2), transforming growth factor β1 (TGF-β1) and interleukin 10 (IL-10). The therapeutic effects of systemic infusion of human UC-MSCs on collagen-induced arthritis (CIA) in a mouse model were explored.
Results
In vitro, UC-MSCs were capable of inhibiting proliferation of FLSs from RA patients, via IL-10, IDO and TGF-β1. Furthermore, the invasive behavior and IL-6 secretion of FLSs were also significantly suppressed. On the other hand, UC-MSCs induced hyporesponsiveness of T cells mediated by PGE2, TGF-β1 and NO and UC-MSCs could promote the expansion of CD4+ Foxp3+ regulatory T cells from RA patients. More importantly, systemic infusion of human UC-MSCs reduced the severity of CIA in a mouse model. Consistently, there were reduced levels of proinflammatory cytokines and chemokines (TNF-α, IL-6 and monocyte chemoattractant protein-1) and increased levels of the anti-inflammatory/regulatory cytokine (IL-10) in sera of UC-MSCs treated mice. Moreover, such treatment shifted Th1/Th2 type responses and induced Tregs in CIA.
Conclusions
In conclusion, human UC-MSCs suppressed the various inflammatory effects of FLSs and T cells of RA in vitro, and attenuated the development of CIA in vivo, strongly suggesting that UC-MSCs might be a therapeutic strategy in RA. In addition, the immunosuppressive activitiy of UC-MSCs could be prolonged by the participation of Tregs.
doi:10.1186/ar3187
PMCID: PMC3046518  PMID: 21080925

Results 1-3 (3)