Yuan K.,University of Sichuan |
Yuan K.,University of North Dakota |
Huang C.,University of Sichuan |
Fox J.,University of North Dakota |
And 6 more authors.
Journal of Cell Science | Year: 2012
Intracellular bacteria have been shown to cause autophagy, which impacts infectious outcomes, whereas extracellular bacteria have not been reported to activate autophagy. Here, we demonstrate that Pseudomonas aeruginosa, a Gram-negative extracellular bacterium, activates autophagy with considerably increased LC3 punctation in both an alveolar macrophage cell line (MH-S) and primary alveolar macrophages. Using the LC3 Gly120 mutant, we successfully demonstrated a hallmark of autophagy, conjugation of LC3 to phosphatidylethanolamine (PE). The accumulation of typical autophagosomes with double membranes was identified morphologically by transmission electron microscopy (TEM). Furthermore, the increase of PE-conjugated LC3 was indeed induced by infection rather than inhibition of lysosome degradation. P. aeruginosa induced autophagy through the classical beclin-1-Atg7-Atg5 pathway as determined by specific siRNA analysis. Rapamycin and IFN-γ (autophagy inducers) augmented bacterial clearance, whereas beclin-1 and Atg5 knockdown reduced intracellular bacteria. Thus, P. aeruginosa-induced autophagy represents a host protective mechanism, providing new insight into the pathogenesis of this infection. © 2012.
Zeldich E.,Boston University |
Chen C.-D.,Boston University |
Avila R.,Renovo Neural, Inc. |
Medicetty S.,Renovo Neural, Inc. |
And 2 more authors.
Journal of Molecular Neuroscience | Year: 2015
The current study examined whether overexpression of Klotho (KL) in transgenic mice can enhance remyelination following cuprizone-induced demyelination and improves the clinical outcome in experimental autoimmune encephalomyelitis (EAE). Demyelination was achieved by feeding transgenic mice overexpressing the transmembrane form of Klotho (KL-OE) and wild-type (WT) littermates cuprizone-containing chow for 6 weeks. The animals were then allowed to remyelinate for 3 weeks. Paraphenylenediamine staining and platelets-derived growth factor receptor α (PDGFRα) and glutathione S-transferase pi (GSTpi) immunohistochemistry were performed on corpus callosum (CC) sections for quantification of myelin and progenitor and mature oligodendrocytes, respectively. The EAE model was induced with the MOG35–55 peptide. The animals were scored daily for clinical symptoms for 30 days. Following 6 weeks of demyelination, both KL-OE mice and WT littermates demonstrated almost complete and comparable demyelination of the CC. However, the level of spontaneous remyelination was increased approximately two-fold in KL-OE mice, although no significant differences in the numbers of PDGFRα and GSTpi-positive cells were observed. Following EAE induction, Klotho overexpression did not affect the clinical scores, likely due to the different roles Klotho plays in the brain and spinal cord. Thus, increasing Klotho expression should be considered as a therapy for enhancing remyelination in the brains of individuals with multiple sclerosis. © 2015, Springer Science+Business Media New York.
Relias V.,Boston Therapeutics |
Saif M.W.,Boston Therapeutics
Journal of the Pancreas | Year: 2014
Ampullary adenocarcinomas have unique biologic and clinical features that result in its improved prognosis versus adenocarcinomas that arise from the distal bile ducts and pancreas. However the histological differentiation and identification of these tumors is not easily accomplished. Two abstracts at this year's ASCO Annual Meeting describe attempts to identify unique methods for distinguishing these tumors. Abstract 4141 described a 92 gene RT-PCR assay that was used for molecular classification of patients with ampullary adenocarcinomas while abstract e15175 looked at mutational status of K-ras in patients with these tumors. The results of their abstracts will be discussed.
Huang Y.,University of Arkansas for Medical Sciences |
Simms A.E.,University of Arkansas for Medical Sciences |
Mazur A.,University of Arkansas for Medical Sciences |
Wang S.,University of Arkansas for Medical Sciences |
And 4 more authors.
Clinical and Experimental Metastasis | Year: 2011
Fibroblast activation protein-α (FAP) is a cell surface, serine protease of the post-prolyl peptidase family that is expressed in human breast cancer but not in normal tissues. Previously, we showed that FAP expression increased tumor growth rates in a mouse model of human breast cancer. Here the role of the proteolytic activities of FAP in promoting tumor growth, matrix degradation and invasion was investigated. Mammary fat pads of female SCID mice were inoculated with breast cancer cells that express FAP and the mice treated with normal saline or Val-boroPro (talabostat); Glu-boroPro (PT-630); or 1-[[(3-hydroxy-1-adamantyl)amino]acetyl]-2-cyano-(S)-pyrrolidine (LAF-237) that inhibit prolyl peptidases. Other mice were injected with breast cancer cells expressing a catalytically inactive mutant of FAP and did not receive inhibitor treatment. PT-630 and LAF-237 did not slow growth of tumors produced by any of the three cell lines expressing FAP. Talabostat slightly decreased the growth rates of the FAP-expressing tumors but because PT-630 and LAF-237 did not, the growth retardation was likely not related to the inhibition of FAP or the related post-prolyl peptidase dipeptidyl peptidase IV. Breast cancer cells expressing a catalytically inactive mutant of FAP (FAPS624A) also produced tumors that grew rapidly. In vitro studies revealed that cells expressing wild type FAP or FAPS624A degrade extracellular matrix (ECM) more extensively, accumulate higher levels of matrix metalloproteinase-9 (MMP-9) in conditioned medium, are more invasive in type I collagen gels, and have altered signaling compared to control transfectants that do not express FAP and form slow growing tumors. We conclude that the proteolytic activity of FAP participates in matrix degradation, but other functions of the protein stimulate increased tumor growth. © 2011 Springer Science+Business Media B.V.
Claria J.,Boston Therapeutics |
Nguyen B.T.,Harvard University |
Madenci A.L.,Harvard University |
Keith Ozaki C.,Harvard University |
Serhan C.N.,Boston Therapeutics
American Journal of Physiology - Cell Physiology | Year: 2013
Adipose tissue is a heterogeneous organ with remarkable variations in fat cell metabolism depending on the anatomical location. However, the pattern and distribution of bioactive lipid mediators between different fat depots and their relationships in complex diseases have not been investigated. Using LC-MS/MS-based metabolo-lipidomics, here we report that human subcutaneous (SC) adipose tissues possess a range of specialized proresolving mediators (SPM) including resolvin (Rv) D1, RvD2, protectin (PD) 1, lipoxin (LX) A4, and the monohydroxy biosynthetic pathway markers of RvD1 and PD1 (17-HDHA), RvE1 (18-HEPE), and maresin 1 (14-HDHA). The "classic" eicosanoids prostaglandin (PG) E2, PGD2, PGF2α, leukotriene (LT) B4, 5-hydroxyeicosatetraenoic acid (5-HETE), 12-HETE, and 15-HETE were also identified in SC fat. SC fat from patients with peripheral vascular disease (PVD) exhibited a marked deficit in PD1 and 17-HDHA levels. Compared with SC, perivascular adipose tissue displayed higher SPM levels, suggesting an enhanced resolution capacity in this fat depot. In addition, augmented levels of eicosanoids and SPM were observed in SC fat surrounding foot wounds. Notably, the profile of SC PGF2α differed significantly when patients were grouped by body mass index (BMI). In the case of peri-wound SC fat, BMI negatively correlated with PGE2. In this tissue, proresolving mediators RvD2 and LXA4 were identified in lower levels than the proinflammatory LTB4. Collectively, these findings demonstrate a diverse distribution of bioactive lipid mediators depending on the localization of human fat depots and uncover a specific SPM pattern closely associated with PVD. © 2013 the American Physiological Society.