Mesenchymal Stem Cells Improve Wound Healing In Vivo via Early Activation of Matrix Metalloproteinase-9 and Vascular Endothelial Growth Factor

We investigated the effects of mesenchymal stem cells (MSCs) on wound healing using a three-dimensional (3D) collagen gel scaffold. Three circular full-thickness skin defects were created on the back of Sprague-Dawley rats. One site was covered with a 3D collagen gel containing 2 × 106 MSCs (MSCs+/3D collagen+). Another site was replaced with a 3D collagen gel without MSCs and the third site was left empty. The wound size was significantly reduced in the MSCs+/3D collagen+ sites. MSCs+/3D collagen+ sites exhibited the most neovascularization. FISH showed that Y-chromosome possessing cells were found within the dermis of MSCs+/3D collagen+ sites. Gelatin zymography revealed that the most intense expression of MMP-9 was detected early in the MSCs+/3D collagen+ sites. Our results indicate that MSCs upregulate the early expression of MMP-9 which induces the early mobilization of VEGF. Thus, MSCs appear to accelerate significantly wound healing via early activation of MMP-9 and VEGF

Platelet-derived growth factor induces p21/WAF1 promoter in vascular smooth muscle cells via activation of an Sp1 site

AbstractMany studies suggested that cyclin-dependent kinase inhibitor (CDKI) p21 acts as a universal inhibitor of cyclin/CDK catalytic activity. This protein has also been shown to be a component of active cyclin/CDK complexes. In addition, it has recently been suggested that p21 serves as an assembly factor in platelet-derived growth factor (PDGF)-stimulated vascular smooth muscle cells (VSMC). However, little is known concerning the molecular mechanisms by which PDGF induces p21 gene expression in VSMC. In this report we demonstrate that PDGF induces the p21 expression at both the mRNA and protein levels. This increase in p21 gene expression was due to activation of the p21 promoter by PDGF. Through both deletion and mutation analysis of the p21 promoter, we defined a 10-bp sequence that is required for the activation of the p21 promoter by PDGF. In addition, gel shift and supershift assays demonstrated that this PDGF-responsive element binds specifically to the transcription factor Sp1. These results demonstrate that Sp1 mediates PDGF-induced p21 gene expression in VSMC. Moreover, immunoblot and immonoprecipitation analysis showed that the level of hyperphosphorylated retinoblastoma protein (Rb) is increased and the protein is physically associated with Sp1 in PDGF-treated cells, indicating that phosphorylated Rb may play a role in regulating Sp1 to activate p21 expression

Acanthopanax koreanum Fruit Waste Inhibits Lipopolysaccharide-Induced Production of Nitric Oxide and Prostaglandin E2 in RAW 264.7 Macrophages

The Acanthopanax koreanum fruit is a popular fruit in Jeju Island, but the byproducts of the alcoholic beverage prepared using this fruit are major agricultural wastes. The fermentability of this waste causes many economic and environmental problems. Therefore, we investigated the suitability of using A. koreanum fruit waste (AFW) as a source of antiinflammatory agents. AFWs were extracted with 80% EtOH. The ethanolic extract was then successively partitioned with hexane, CH2Cl2, EtOAc, BuOH, and water. The results indicate that the CH2Cl2 fraction (100 μg/mL) of AFW inhibited the LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production in RAW 264.7 cells by 79.6% and 39.7%, respectively. These inhibitory effects of the CH2Cl2 fraction of AFWs were accompanied by decreases in the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins and iNOS and COX-2 mRNA in a dose-dependent pattern. The CH2Cl2 fraction of AFWs also prevented degradation of IκB-α in a dose-dependent manner. Ursolic acid was identified as major compound present in AFW, and CH2Cl2 extracts by high performance liquid chromatography (HPLC). Furthermore using pure ursolic acid as standard and by HPLC, AFW and CH2Cl2 extracts was found to contain 1.58 mg/g and 1.75 mg/g, respectively. Moreover, we tested the potential application of AFW extracts as a cosmetic material by performing human skin primary irritation tests. In these tests, AFW extracts did not induce any adverse reactions. Based on these results, we suggest that AFW extracts be considered possible anti-inflammatory candidates for topical application