Medicine and Health Sciences Commons^™

Adiponectin Inhibits Oxidative/Nitrative Stress During Myocardial Ischemia And Reperfusion Via Pka Signaling., Yanqing Zhang, Xiao-Liang Wang, Jianli Zhao, Ya-Jing Wang, Wayne Bond Lau, Yue-Xing Yuan, Er-He Gao, Walter J. Koch, Xin-Liang Ma

Department of Emergency Medicine Faculty Papers

The cardioprotective effects of adiponectin (APN) against myocardial ischemia/reperfusion (MI/R) injury are well known. However, comprehension of the mechanisms mediating intracellular APN signaling remains incomplete. We recently demonstrate the antioxidant/antinitrative effects of APN are not dependent on AMPK. Protein kinase A (PKA) has been previously shown to be activated by APN, with uncertain relevance to APN cardiac protection. The current study determined whether the antioxidative/antinitrative effect of APN is mediated by PKA. Administration of APN (2 μg/g) 10 min before reperfusion significantly enhanced cardiac PKA activity, reduced oxidative stress, and decreased infarct size. Knockdown of cardiac PKA expression (PKA-KD) by …

Targeting Cell Cycle And Hormone Receptor Pathways In Cancer., C E S Comstock, M A Augello, J F Goodwin, R De Leeuw, M J Schiewer, W F Ostrander, R A Burkhart, A K Mcclendon, Peter Mccue, Edouard J. Trabulsi, Costas D. Lallas, Leonard G Gomella, Md, M M Centenera, Jonathan Brody, Md, L M Butler, W D Tilley, K E Knudsen, Phd

Department of Cancer Biology Faculty Papers

The cyclin/cyclin-dependent kinase (CDK)/retinoblastoma (RB)-axis is a critical modulator of cell cycle entry and is aberrant in many human cancers. New nodes of therapeutic intervention are needed that can delay or combat the onset of malignancies. The antitumor properties and mechanistic functions of PD-0332991 (PD; a potent and selective CDK4/6 inhibitor) were investigated using human prostate cancer (PCa) models and primary tumors. PD significantly impaired the capacity of PCa cells to proliferate by promoting a robust G1-arrest. Accordingly, key regulators of the G1-S cell cycle transition were modulated including G1 cyclins D, E and A. Subsequent investigation demonstrated the ability …

Intestinal Gucy2c Prevents Tgf-Β Secretion Coordinating Desmoplasia And Hyperproliferation In Colorectal Cancer., Ahmara V Gibbons, Jieru Egeria Lin, Gilbert Won Kim, Glen P Marszalowicz, Peng Li, Brian Arthur Stoecker, Erik S Blomain, Satish Rattan, Adam E. Snook, Stephanie Schulz, Scott A Waldman

Department of Pharmacology and Experimental Therapeutics Faculty Papers

Tumorigenesis is a multistep process that reflects intimate reciprocal interactions between epithelia and underlying stroma. However, tumor-initiating mechanisms coordinating transformation of both epithelial and stromal components are not defined. In humans and mice, initiation of colorectal cancer is universally associated with loss of guanylin and uroguanylin, the endogenous ligands for the tumor suppressor guanylyl cyclase C (GUCY2C), disrupting a network of homeostatic mechanisms along the crypt-surface axis. Here, we reveal that silencing GUCY2C in human colon cancer cells increases Akt-dependent TGF-β secretion, activating fibroblasts through TGF-β type I receptors and Smad3 phosphorylation. In turn, activating TGF-β signaling induces fibroblasts to …

Thioredoxin Reductase Was Nitrated In The Aging Heart After Myocardial Ischemia/Reperfusion., Ke Wang, Jie Zhang, Xiaoliang Wang, Xin Liu, Lin Zuo, Kehua Bai, Jianyu Shang, Lu Ma, Teng Liu, Li Wang, Wen Wang, Xin-Liang Ma, Huirong Liu

Department of Emergency Medicine Faculty Papers

The age-related loss of anti-oxidant defense reduces recovery from myocardial ischemia/reperfusion injury (MI/R) in aged people. Our previous data showed that inactivation of thioredoxin (Trx) was involved in enhanced aging MI/R injury. Thioredoxin reductase (TrxR), the enzyme known to regulate Trx, is less efficient with age. The aim of the current study was to determine why TrxR activity was reduced and whether reduced TrxR activity contributed to enhanced aging MI/R injury. Both Trx and TrxR activity were decreased in the aging heart, and this difference was further amplified after MI/R. However, MI/R injury did not change TrxR expression between young …

Cyclin D1 Determines Estrogen Signaling In The Mammary Gland In Vivo., Mathew C Casimiro, Chenguang Wang, Z Li, Gabriele Disante, Nicole E Willmart, Sankar Addya, Lei Chen, Yang Liu, Michael P. Lisanti, Richard Pestell

Department of Cancer Biology Faculty Papers

The CCND1 gene, which is frequently overexpressed in cancers, encodes the regulatory subunit of a holoenzyme that phosphorylates the retinoblastoma protein. Although it is known that cyclin D1 regulates estrogen receptor (ER)α transactivation using heterologous reporter systems, the in vivo biological significance of cyclin D1 to estrogen-dependent signaling, and the molecular mechanisms by which cyclin D1 is involved, are yet to be elucidated. Herein, genome-wide expression profiling conducted of 17β-estradiol-treated castrated virgin mice deleted of the Ccnd1 gene demonstrated that cyclin D1 determines estrogen-dependent gene expression for 88% of estrogen-responsive genes in vivo. In addition, expression profiling of 17β-estradiol-stimulated cyclin …

Erosive Arthritis And Hepatic Granuloma Formation Induced By Peptidoglycan Polysaccharide In Rats Is Aggravated By Prasugrel Treatment., Analia E Garcia, Mario C Rico, Elisabetta Liverani, Raul A Dela Cadena, Paul F. Bray, Satya P Kunapuli

Cardeza Foundation for Hematologic Research

Administration of the thienopyridine P2Y12 receptor antagonist, clopidogrel, increased the erosive arthritis induced by peptidoglycan polysaccharide (PG-PS) in rats or by injection of the arthritogenic K/BxN serum in mice. To determine if the detrimental effects are caused exclusively by clopidogrel, we evaluated prasugrel, a third-generation thienopyridine pro-drug, that contrary to clopidogrel is mostly metabolized into its active metabolite in the intestine. Prasugrel effects were examined on the PG-PS-induced arthritis rat model. Erosive arthritis was induced in Lewis rats followed by treatment with prasugrel for 21 days. Prasugrel treated arthritic animals showed a significant increase in the inflammatory response, compared with …

Smooth Muscle Fascicular Reorientation Is Required For Esophageal Morphogenesis And Dependent On Cdo., Anthony I Romer, Jagmohan Singh, Satish Rattan, Robert S Krauss

Department of Medicine Faculty Papers

Postnatal maturation of esophageal musculature involves proximal-to-distal replacement of smooth muscle with skeletal muscle by elusive mechanisms. We report that this process is impaired in mice lacking the cell surface receptor Cdo and identify the underlying developmental mechanism. A myogenic transition zone containing proliferative skeletal muscle precursor cells migrated in a proximal-distal direction, leaving differentiated myofibers in its wake. Distal to the transition zone, smooth muscle fascicles underwent a morphogenetic process whereby they changed their orientation relative to each other and to the lumen. Consequently, a path was cleared for the transition zone, and smooth muscle ultimately occupied only the …

The Tweak Receptor Fn14 Is A Therapeutic Target In Melanoma: Immunotoxins Targeting Fn14 Receptor For Malignant Melanoma Treatment., Hong Zhou, Suhendan Ekmekcioglu, John W Marks, Khalid A Mohamedali, Kaushal Asrani, Keeley K Phillips, Sharron A N Brown, Emily Cheng, Michele B Weiss, Walter N Hittelman, Nhan L Tran, Hideo Yagita, Jeffrey A Winkles, Michael G Rosenblum

Department of Cancer Biology Faculty Papers

Fibroblast growth factor-inducible protein 14 (Fn14), the cell surface receptor for tumor necrosis factor-like weak inducer of apoptosis (TWEAK), is overexpressed in various human solid tumor types and can be a negative prognostic indicator. We detected Fn14 expression in ∼60% of the melanoma cell lines we tested, including both B-Raf WT and B-Raf(V600E) lines. Tumor tissue microarray analysis indicated that Fn14 expression was low in normal skin, but elevated in 173/190 (92%) of primary melanoma specimens and in 86/150 (58%) of melanoma metastases tested. We generated both a chemical conjugate composed of the recombinant gelonin (rGel) toxin and the anti-Fn14 …

Lymphotoxin-Α Is A Novel Adiponectin Expression Suppressor Following Myocardial Ischemia/Reperfusion., Wayne Bond Lau, Yanqing Zhang, Jianli Zhao, Baojiang Liu, Xiaoliang Wang, Yuexing Yuan, Theodore A. Christopher, Bernard Lopez, Erhe Gao, Walter J. Koch, Xin L. Ma, Yajing Wang

Department of Emergency Medicine Faculty Papers

Recent clinical observations demonstrate adiponectin (APN), an adipocytokine with potent cardioprotective actions, is significantly reduced following myocardial ischemia/reperfusion (MI/R). However, mechanisms responsible for MI/R-induced hypoadiponectinemia remain incompletely understood. Adult male mice were subjected to 30-min MI followed by varying reperfusion periods. Adipocyte APN mRNA and protein expression and plasma APN and TNFα concentrations were determined. APN expression/production began to decline 3 h after reperfusion (reaching nadir 12 h after reperfusion), returning to control levels 7 days after reperfusion. Plasma TNFα levels began to increase 1 h after reperfusion, peaking at 3 h and returning to control levels 24 h after …

Inhibitory Effect Of Il-17 On Neural Stem Cell Proliferation And Neural Cell Differentiation., Zichen Li, Ke Li, Lin Zhu, Quancheng Kan, Yaping Yan, Priyanka Kumar, Hui Xu, Abdolmohamad Rostami, Guang-Xian Zhang

Department of Neurology Faculty Papers

BACKGROUND: IL-17, a Th17 cell-derived proinflammatory molecule, has been found to play an important role in the pathogenesis of autoimmune diseases, including multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). While IL-17 receptor (IL-17R) is expressed in many immune-related cells, microglia, and astrocytes, it is not known whether IL-17 exerts a direct effect on neural stem cells (NSCs) and oligodendrocytes, thus inducing inflammatory demyelination in the central nervous system.

METHODS: We first detected IL-17 receptor expression in NSCs with immunostaining and real time PCR. We then cultured NSCs with IL-17 and determined NSC proliferation by neurosphere formation …

Identification Of Phosphorylation Sites In The Cooh-Terminal Tail Of The Μ-Opioid Receptor., Ying-Ju Chen, Sue Oldfield, Adrian J. Butcher, Andrew B. Tobin, Kunal Saxena, Vsevolod V. Gurevich, Jeffrey L. Benovic, Graeme Henderson, Eamonn Kelly

Department of Biochemistry and Molecular Biology Faculty Papers

Phosphorylation is considered a key event in the signalling and regulation of the μ opioid receptor (MOPr). Here, we used mass spectroscopy to determine the phosphorylation status of the C-terminal tail of the rat MOPr expressed in human embryonic kidney 293 (HEK-293) cells. Under basal conditions, MOPr is phosphorylated on Ser(363) and Thr(370), while in the presence of morphine or [D-Ala2, NMe-Phe4, Gly-ol5]-enkephalin (DAMGO), the COOH terminus is phosphorylated at three additional residues, Ser(356) , Thr(357) and Ser(375). Using N-terminal glutathione S transferase (GST) fusion proteins of the cytoplasmic, C-terminal tail of MOPr and point mutations of the same, we …

Cis And Trans Regulatory Mechanisms Control Ap2-Mediated B Cell Receptor Endocytosis Via Select Tyrosine-Based Motifs., Kathleen Busman-Sahay, Lisa Drake, Anand Sitaram, Michael Marks, James R Drake

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Following antigen recognition, B cell receptor (BCR)-mediated endocytosis is the first step of antigen processing and presentation to CD4+ T cells, a crucial component of the initiation and control of the humoral immune response. Despite this, the molecular mechanism of BCR internalization is poorly understood. Recently, studies of activated B cell-like diffuse large B cell lymphoma (ABC DLBCL) have shown that mutations within the BCR subunit CD79b leads to increased BCR surface expression, suggesting that CD79b may control BCR internalization. Adaptor protein 2 (AP2) is the major mediator of receptor endocytosis via clathrin-coated pits. The BCR contains five putative AP2-binding …