OBJECTIVE-Progranulin is an important molecule in inflammatory response. Chronic inflammation is frequently associated with central obesity and associated disturbances; however, the role of circulating progranulin in human obesity, type 2 diabetes, and dyslipidemia is unknown.RESEARCH DESIGN AND METHODS-For the measurement of progranulin serum concentrations, we developed an enzymelinked immunosorbent assay (ELISA). Using this ELISA, we assessed circulating progranulin in a cross-sectional study of 209 subjects with a wide range of obesity, body fat distribution, insulin sensitivity, and glucose tolerance and in 60 individuals with normal (NGT) or impaired (IGT) glucose tolerance or type 2 diabetes before and after a 4-week physical training program. Progranulin mRNA and protein expression was measured in paired samples of omental and subcutaneous adipose tissue (adipocytes and cells of the stromal vascular fraction) from 55 lean or obese individuals. Measurement of Erk activation and chemotactic activity induced by progranulin in vitro was performed using THP-1-based cell migration assays.RESULTS-Progranulin serum concentrations were significantly higher in individuals with type 2 diabetes compared with NGT and in obese subjects with predominant visceral fat accumulation. Circulating progranulin significantly correlates with BMI, macrophage infiltration in omental adipose tissue, C-reactive protein (CRP) serum concentrations, A1C values, and total cholesterol. Multivariable linear regression analyses revealed CRP levels as the strongest independent predictor of circulating progranulin. The extent of in vitro progranulin-mediated chemotaxis is similar to that of monocyte chemoattractant protein-1 but independent of G␣. Moreover, in type 2 diabetes, but not in IGT and NGT individuals, physical training for 4 weeks resulted in significantly decreased circulating progranulin levels.CONCLUSIONS-Elevated progranulin serum concentrations are associated with visceral obesity, elevated plasma glucose, and dyslipidemia. We identified progranulin as a novel marker of chronic inflammation in obesity and type 2 diabetes that closely reflects omental adipose tissue macrophage infiltration. Physical training significantly reduces elevated circulating progranulin in patients with type 2 diabetes. Diabetes 58:627-636, 2009
Efficient oral administration of protein-based therapeutics faces significant challenges due to degradation from the highly acidic conditions present in the stomach and proteases present in the digestive tract. Herein, investigations into spike-covered sunflower sporopollenin exine capsules (SECs) for oral protein delivery using bovine serum albumin (BSA) as a model drug are reported and provide significant insights into the optimization of SEC extraction, SEC loading, and controlled release. The phosphoric-acid-based SEC extraction process is optimized. Compound loading is shown to be driven by the evacuation of air bubbles from SEC cavities through the porous SEC shell wall, and vacuum loading is shown to be the optimal loading method. Three initial BSA-loading proportions are evaluated, leading to a practical loading efficiency of 22.3 ± 1.5 wt% and the determination that the theoretical maximum loading is 46.4 ± 2.5 wt%. Finally, an oral delivery formulation for targeted intestinal delivery is developed by tableting BSA-loaded SECs and enteric coating. BSA release is inhibited for 2 h in simulated gastric conditions followed by 100% release within 8 h in simulated intestinal conditions. Collectively, these results indicate that sunflower SECs provide a versatile platform for the oral delivery of therapeutics.
Mesenchymal stem cells (MSCs) have the potential to be a viable therapy against various diseases due to their paracrine effects, such as secretion of immunomodulatory, trophic and protective factors. These cells are known to be distributed within various organs and tissues. Although they possess the same characteristics, MSCs from different sources are believed to have different secretion potentials and patterns, which may influence their therapeutic effects in disease environments. We characterized the protein secretome of adipose (AD), bone marrow (BM), placenta (PL), and Wharton’s jelly (WJ)-derived human MSCs by using conditioned media and analyzing the secretome by mass spectrometry and follow-up bioinformatics. Each MSC secretome profile had distinct characteristics depending on the source. However, the functional analyses of the secretome from different sources showed that they share similar characteristics, such as cell migration and negative regulation of programmed cell death, even though differences in the composition of the secretome exist. This study shows that the secretome of fetal-derived MSCs, such as PL and WJ, had a more diverse composition than that of AD and BM-derived MSCs, and it was assumed that their therapeutic potential was greater because of these properties.
Purpose: The potential of metastasis can be predicted from clinical features like tumor size, histologic grade, and gene expression patterns. We examined the whole-genome transcriptomic profile of a xenograft model of breast cancer to understand the characteristics of brain metastasis. Experimental Design: Variants of the MDA-MB-435 cell were established from experimental brain metastases. The LvBr2 variant was isolated from lesions in a mouse injected in the left ventricle of the heart, and these cells were used for two cycles of injection into the internal carotid artery and selection of brain lesions, resulting in the Br4 variant. To characterize the different metastatic variants, we examined the gene expression profile of MDA-MB-435, LvBr2, and Br4 cells using microarrays. Results: We could identify 2,016 differentially expressed genes in Br4 by using the F test. Various metastasis-related genes and a number of genes related to angiogenesis, migration, tumorigenesis, and cell cycle were differentially expressed by the Br4 cells. Notably, the Notch signaling pathway was activated in Br4, with increased Jag2 mRNA, activated Notch intracellular domain, and Notch intracellular domain/CLS promoter-luciferase activity. Br4 cells were more migratory and invasive than MDA-MB-435 cells in collagen and Matrigel Transwell assays, and the migration and invasion of Br4 cells were significantly inhibited by inactivation of Notch signaling using DAPT, a g-secretase inhibitor, and RNA interference^mediated knockdown of Jagged 2 and Notch1. Conclusions: Taken together, these results suggest that we have isolated variants of a human cancer cell line with enhanced brain metastatic properties, and the activation of Notch signaling might play a crucial role in brain metastasis.
LL-37 is a human cathelicidin antimicrobial peptide that is released in the skin after injury and acts to defend against infection and modulate the local cellular immune response. We observed in human dermal keloids that fibrosis was inversely related to the expression of cathelicidin and sought to determine how LL-37 influenced expression of types I and III collagen genes in dermal fibroblasts. At nano-molar concentrations, LL-37 inhibited baseline and transforming growth factor-β-induced collagen expression. At these concentrations, LL-37 also induced phosphorylation of extracellular signal-regulated kinase (ERK) within 30 minutes. Activation of ERK, and the activation of a G-protein-dependent pathway, was essential for inhibition of collagen expression as pertussis toxin or an inhibitor of ERK blocked the inhibitory effects of LL-37. c-Jun N-terminal kinase and p38 mitogen-activated protein kinase inhibitors did not alter the effects of cathelicidin. Silencing of the Ets-1 reversed inhibitory effects of LL-37. Taken together, these findings show that LL-37 can directly act on dermal fibroblasts and may have antifibrotic action during the wound repair process.
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