Medicine and Health Sciences Commons^™

Sphingosine-1-Phosphate-Mediated Mobilization Of Hematopoietic Stem/Progenitor Cells During Intravascular Hemolysis Requires Attenuation Of Sdf-1-Cxcr4 Retention Signaling In Bone Marrow, Kasia Mierzejewska, Yuri M. Klyachkin, Janina Ratajczak, Ahmed Abdel-Latif, Magda Kucia, Mariusz Z. Ratajczak

Saha Cardiovascular Research Center Faculty Publications

Sphingosine-1-phosphate (S1P) is a crucial chemotactic factor in peripheral blood (PB) involved in the mobilization process and egress of hematopoietic stem/progenitor cells (HSPCs) from bone marrow (BM). Since S1P is present at high levels in erythrocytes, one might assume that, by increasing the plasma S1P level, the hemolysis of red blood cells would induce mobilization of HSPCs. To test this assumption, we induced hemolysis in mice by employing phenylhydrazine (PHZ). We observed that doubling the S1P level in PB from damaged erythrocytes induced only a marginally increased level of mobilization. However, if mice were exposed to PHZ together with the …

Divergent Antibody Subclass And Specificity Profiles But Not Protective Hla-B Alleles Are Associated With Variable Antibody Effector Function Among Hiv-1 Controllers, Jennifer I. Lai, Anna F. Licht, Anne-Sophie Dugast, Todd Suscovich, Ickwon Choi, Chris Bailey-Kellogg, Galit Alter, Margaret E. Ackerman

Dartmouth Scholarship

Understanding the coordination between humoral and cellular immune responses may be the key to developing protective vaccines, and because genetic studies of long-term HIV-1 nonprogressors have associated specific HLA-B alleles with spontaneous control of viral replication, this subject group presents an opportunity to investigate relationships between arms of the adaptive immune system. Given evidence suggesting that cellular immunity may play a role in viral suppression, we sought to determine whether and how the humoral immune response might vary among controllers. Significantly, Fc-mediated antibody effector functions have likewise been associated with durable viral control. In this study, we compared the effector …

Racial Differences In Human Platelet Par4 Reactivity Reflect Expression Of Pctp And Mir-376c., Leonard Edelstein, Lukas M Simon, Raúl Teruel Montoya, Michael Holinstat, Edward S Chen, Angela Bergeron, Xianguo Kong, Srikanth Nagalla, Narla Mohandas, David E Cohen, Jing-Fei Dong, Chad Shaw, Paul Bray

Cardeza Foundation for Hematologic Research

Racial differences in the pathophysiology of atherothrombosis are poorly understood. We explored the function and transcriptome of platelets in healthy black (n = 70) and white (n = 84) subjects. Platelet aggregation and calcium mobilization induced by the PAR4 thrombin receptor were significantly greater in black subjects. Numerous differentially expressed RNAs were associated with both race and PAR4 reactivity, including PCTP (encoding phosphatidylcholine transfer protein), and platelets from black subjects expressed higher levels of PC-TP protein. PC-TP inhibition or depletion blocked PAR4- but not PAR1-mediated activation of platelets and megakaryocytic cell lines. miR-376c levels were differentially expressed by race and …

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 …

Hrs Promotes Ubiquitination And Mediates Endosomal Trafficking Of Smoothened In Drosophila Hedgehog Signaling, Jun-Kai Fan, Kai Jiang, Yajuan Liu, Jianhang Jia

Markey Cancer Center Faculty Publications

In Hedgehog (Hh) signaling, the seven-transmembrane protein Smoothened (Smo) acts as a signal transducer that is regulated by phosphorylation, ubiquitination, and cell surface accumulation. However, it is not clear how Smo cell surface accumulation and intracellular trafficking are regulated. Here, we demonstrate that inactivation of Hrs by deletion or RNAi accumulates Smo in the late endosome that is marked by late endosome markers. Inactivation of Hrs enhances the wing defects caused by dominant-negative Smo. We show that Hrs promotes Smo ubiquitination, deleting the ubiquitin-interacting-motif (UIM) in Hrs abolishes the ability of Hrs to regulate Smo ubiquitination. However, the UIM domain …

The G-Protein-Coupled Estrogen Receptor Agonist G-1 Suppresses Proliferation Of Ovarian Cancer Cells By Blocking Tubulin Polymerization., Cheng Wang, Xiangmin Lv, Chunbo He, G Hua, M-Y Tsai, John S. Davis

Journal Articles: Obstetrics & Gynecology

The G-protein-coupled estrogen receptor 1 (GPER) has recently been reported to mediate the non-genomic action of estrogen in different types of cells and tissues. G-1 (1-[4-(6-bromobenzo[1,3] dioxol-5yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinolin-8-yl]-ethanone) was developed as a potent and selective agonist for GPER. G-1 has been shown to induce the expression of genes and activate pathways that facilitate cancer cell proliferation by activating GPER. Here we demonstrate that G-1 has an anticancer potential with a mechanism similar to vinca alkaloids, the commonly used chemotherapy drugs. We found that G-1 blocks tubulin polymerization and thereby interrupts microtubule assembly in ovarian cancer cells leading to the arrest of …

Cardiac Fibroblast-Dependent Extracellular Matrix Accumulation Is Associated With Diastolic Stiffness In Type 2 Diabetes., Kirk R. Hutchinson, C. Kevin Lord, T. Aaron West, James A. Stewart

College of Arts and Sciences Publications and Scholarship

Cardiovascular complications are a leading cause of death in patients with type 2 diabetes mellitus (T2DM). Diastolic dysfunction is one of the earliest manifestations of diabetes-induced changes in left ventricular (LV) function, and results from a reduced rate of relaxation and increased stiffness. The mechanisms responsible for increased stiffness are not completely understood. Chronic hyperglycemia, advanced glycation endproducts (AGEs), and increased levels of proinflammatory and profibrotic cytokines are molecular pathways known to be involved in regulating extracellular matrix (ECM) synthesis and accumulation resulting in increased LV diastolic stiffness. Experiments were conducted using a genetically-induced mouse model of T2DM generated by …

Lineage-Specific T-Cell Responses To Cancer Mucosa Antigen Oppose Systemic Metastases Without Mucosal Inflammatory Disease., Adam Snook, Peng Li, Benjamin J Stafford, Elizabeth J Faul, Lan Huang, Ruth C Birbe, Alessandro Bombonati, Stephanie Schulz, Matthias Schnell, Laurence Eisenlohr, Scott Waldman

Adam E Snook

Cancer mucosa antigens are emerging as a new category of self-antigens expressed normally in immunologically privileged mucosal compartments and universally by their derivative tumors. These antigens leverage the established immunologic partitioning of systemic and mucosal compartments, limiting tolerance opposing systemic antitumor efficacy. An unresolved issue surrounding self-antigens as immunotherapeutic targets is autoimmunity following systemic immunization. In the context of cancer mucosa antigens, immune effectors to self-antigens risk amplifying mucosal inflammatory disease promoting carcinogenesis. Here, we examined the relationship between immunotherapy for systemic colon cancer metastases targeting the intestinal cancer mucosa antigen guanylyl cyclase C (GCC) and its effect on inflammatory …

Gucy2c Opposes Systemic Genotoxic Tumorigenesis By Regulating Akt-Dependent Intestinal Barrier Integrity, Jieru Egeria Lin, Adam Eugene Snook, Peng Li, Brian Arthur Stoecker, Gilbert Won Kim, Michael Sullivan Magee, Alex Vladimir Mejia Garcia, Michael Anthony Valentino, Terry Hyslop, Stephanie Schulz, Scott Arthur Waldman

Adam E Snook

The barrier separating mucosal and systemic compartments comprises epithelial cells, annealed by tight junctions, limiting permeability. GUCY2C recently emerged as an intestinal tumor suppressor coordinating AKT1-dependent crypt-villus homeostasis. Here, the contribution of GUCY2C to barrier integrity opposing colitis and systemic tumorigenesis is defined. Mice deficient in GUCY2C (Gucy2c−/−) exhibited barrier hyperpermeability associated with reduced junctional proteins. Conversely, activation of GUCY2C in mice reduced barrier permeability associated with increased junctional proteins. Further, silencing GUCY2C exacerbated, while activation reduced, chemical barrier disruption and colitis. Moreover, eliminating GUCY2C amplified, while activation reduced, systemic oxidative DNA damage. This genotoxicity was associated with increased spontaneous …

Expression Of C-Fos In Hilar Mossy Cells Of The Dentate Gyrus In Vivo., Aine M Duffy, Michael J Schaner, Jeannie Chin, Helen E Scharfman

Department of Neuroscience Faculty Papers

Granule cells (GCs) of the dentate gyrus (DG) are considered to be quiescent--they rarely fire action potentials. In contrast, the other glutamatergic cell type in the DG, hilar mossy cells (MCs) often have a high level of spontaneous activity based on recordings in hippocampal slices. MCs project to GCs, so activity in MCs could play an important role in activating GCs. Therefore, we investigated whether MCs were active under basal conditions in vivo, using the immediate early gene c-fos as a tool. We hypothesized that MCs would exhibit c-fos expression even if rats were examined randomly, under normal housing conditions. …

The Minimum M3-M4 Loop Length Of Neurotransmitter-Activated Pentameric Receptors Is Critical For The Structural Integrity Of Cytoplasmic Portals, Daniel T. Baptista-Hon, Tarek Z. Deeb, Jeremy J. Lambert, John A. Peters, Tim G. Hales

Pharmacology and Physiology Faculty Publications

The 5-HT₃A receptor homology model, based on the partial structure of the nicotinic acetylcholine receptor from Torpedo marmorata, reveals an asymmetric ion channel with five portals framed by adjacent helical amphipathic (HA) stretches within the 114-residue loop between the M3 and M4 membrane-spanning domains. The positive charge of Arg-436, located within the HA stretch, is a rate-limiting determinant of single channel conductance (γ). Further analysis reveals that positive charge and volume of residue 436 are determinants of 5-HT₃A receptor inward rectification, exposing an additional role for portals. A structurally unresolved stretch of 85 residues constitutes …

Fetal Hemorrhage And Platelet Dysfunction In Slp-76-Deficient Mice., J. Clements, J. Lee, B. Gross, Baoli Yang, J. Olson, A. Sandra, S. Watson, S. Lentz, G. Koretzky

Baoli Yang

The adapter protein SLP-76 is expressed in T lymphocytes and hematopoietic cells of the myeloid lineage, and is known to be a substrate of the protein tyrosine kinases that are activated after ligation of the T-cell antigen receptor. Transient overexpression of SLP-76 in a T-cell line potentiates transcriptional activation after T-cell receptor ligation, while loss of SLP-76 expression abrogates several T-cell receptor-dependent signaling pathways. Mutant mice that lack SLP-76 manifest a severe block at an early stage of thymocyte development, implicating SLP-76 in signaling events that promote thymocyte maturation. While it is clear that SLP-76 plays a key role in …

Requirement For The Leukocyte-Specific Adapter Protein Slp-76 For Normal T Cell Development., J. Clements, Baoli Yang, S. Ross-Barta, S. Eliason, R. Hrstka, R. Williamson, G. Koretzky

Baoli Yang

The leukocyte-specific adapter molecule SLP-76 (Src homology 2 domain-containing leukocyte protein of 76 kilodaltons) is rapidly phosphorylated on tyrosine residues after receptor ligation in several hematopoietically derived cell types. Mice made deficient for SLP-76 expression contained no peripheral T cells as a result of an early block in thymopoiesis. Macrophage and natural killer cell compartments were intact in SLP-76-deficient mice, despite SLP-76 expression in these lineages in wild-type mice. Thus, the SLP-76 adapter protein is required for normal thymocyte development and plays a crucial role in translating signals mediated by pre-T cell receptors into distal biochemical events.

The Tumor Suppressor Tere1 (Ubiad1) Prenyltransferase Regulates The Elevated Cholesterol Phenotype In Castration Resistant Prostate Cancer By Controlling A Program Of Ligand Dependent Sxr Target Genes., William J. Fredericks, Jorge Sepulveda, Priti Lai, John E. Tomaszewski, Ming-Fong Lin, Terry Mcgarvey, Frank J. Rauscher, S. Bruce Malkowicz

Journal Articles: Biochemistry & Molecular Biology

Castrate-Resistant Prostate Cancer (CRPC) is characterized by persistent androgen receptor-driven tumor growth in the apparent absence of systemic androgens. Current evidence suggests that CRPC cells can produce their own androgens from endogenous sterol precursors that act in an intracrine manner to stimulate tumor growth. The mechanisms by which CRPC cells become steroidogenic during tumor progression are not well defined. Herein we describe a novel link between the elevated cholesterol phenotype of CRPC and the TERE1 tumor suppressor protein, a prenyltransferase that synthesizes vitamin K-2, which is a potent endogenous ligand for the SXR nuclear hormone receptor. We show that 50% …

Id4 Deficiency Attenuates Prostate Development And Promotes Pin-Like Lesions By Regulating Androgen Receptor Activity And Expression Of Nkx3.1 And Pten, Pankaj Sharma, Ashley Knowell, Swathi Chinaranagari, Shravan Komaragiri, Peri Nagappan, Divya Patel, Mathew C. Havrda, Jaideep Chaudhary

Dartmouth Scholarship

Background: Inhibitor of differentiation 4 (Id4), a member of the helix-loop-helix family of transcriptional regulators has emerged as a tumor suppressor in prostate cancer. Id4 is expressed in the normal prostate where its expression is also regulated by androgens. In this study we investigated the effect of loss of Id4 (Id4-/-) on adult prostate morphology. Methods: Histological analysis was performed on prostates from 6-8 weeks old Id4-/-, Id4+/- and Id4+/+ mice. Expression of Id1, Sox9, Myc, androgen receptor, Akt, p-Akt, Pten and Nkx3.1 was investigated by immunohistochemistry. Androgen receptor binding on NKX3.1 promoter was studied by chromatin immuno-precipitation. Id4 was …

Bioactive Lipids And Cationic Antimicrobial Peptides As New Potential Regulators For Trafficking Of Bone Marrow-Derived Stem Cells In Patients With Acute Myocardial Infarction, Anush V. Karapetyan, Yuri M. Klyachkin, Samy Selim, Manjula Sunkara, Khaled M. Ziada, Donald A. Cohen, Ewa K. Zuba-Surma, Janina Ratajczak, Susan S. Smyth, Mariusz Z. Ratajczak, Andrew J. Morris, Ahmed Abdel-Latif

Internal Medicine Faculty Publications

Acute myocardial infarction (AMI) triggers mobilization of stem cells from bone marrow (BM) into peripheral blood (PB). Based on our observation that the bioactive sphingophospholipids, sphingosine-1 phosphate (S1P), and ceramide-1 phosphate (C1P) regulate trafficking of hematopoietic stem cells (HSCs), we explored whether they also direct trafficking of non-hematopoietic stem cells (non-HSCs). We detected a 3–6-fold increase in circulating CD34+, CD133+, and CXCR4+ lineage-negative (Lin−)/CD45− cells that are enriched in non-HSCs [including endothelial progenitors (EPCs) and very small embryonic-like stem cells (VSELs)] in PB from AMI patients (P<0.05 vs. controls). Concurrently, we measured a 3-fold increase in S1P and C1P levels in plasma from AMI patients. At the same time, plasma obtained at hospital admission and 6 h after AMI strongly chemoattracted human BM-derived CD34+/Lin− and CXCR4+/Lin− cells in Transwell chemotaxis assays. This effect of plasma was blunted after depletion of S1P level by charcoal stripping and was further inhibited by the specific S1P1 receptor antagonist such as W146 and VPC23019. We also noted that the expression of S1P receptor 1 (S1P1), which is dominant in naïve BM, is reduced after the exposure to S1P at concentrations similar to the plasma S1P levels in patients with AMI, thus influencing the role of S1P in homing to the injured myocardium. Therefore, we examined mechanisms, other than bioactive lipids, that may contribute to the homing of BM non-HSCs to the infarcted myocardium. Hypoxic cardiac tissue increases the expression of cathelicidin and β-2 defensin, which could explain why PB cells isolated from patients with AMI migrated more efficiently to a low, yet physiological, gradient of stromal-derived factor-1 in Transwell migration assays. Together, these observations suggest that while elevated S1P and C1P levels early in the course of AMI may trigger mobilization of non-HSCs into PB, cathelicidin and β-2 defensin could play an important role in their homing to damaged myocardium.

Dynamic Dual-Tracer Mri-Guided Fluorescence Tomography To Quantify Receptor Density In Vivo, Scott C. Davis, Kimberley S. Samkoe, Kenneth M. Tichauer, Kristian J. Sexton, Jason R. Gunn, Sophie J. Deharvengt, Tayyaba Hasan, Brian W. Pogue

Dartmouth Scholarship

The up-regulation of cell surface receptors has become a central focus in personalized cancer treatment; however, because of the complex nature of contrast agent pharmacokinetics in tumor tissue, methods to quantify receptor binding in vivo remain elusive. Here, we present a dual-tracer optical technique for noninvasive estimation of specific receptor binding in cancer. A multispectral MRI-coupled fluorescence molecular tomography system was used to image the uptake kinetics of two fluorescent tracers injected simultaneously, one tracer targeted to the receptor of interest and the other tracer a nontargeted reference. These dynamic tracer data were then fit to a dual-tracer compartmental model …

Intrinsic Differences In The Response Of The Human Lutropin Receptor Versus The Human Follitropin Receptor To Activating Mutations, Meilin Zhang, Ya-Xiong Tao, Ginny Ryan, Xiuyan Feng, Francesca Fanelli, Deborah Segaloff

Ginny L. Ryan

In contrast to the human lutropin receptor (hLHR), very few naturally occurring activating mutations of the structurally related human follitropin receptor (hFSHR) have been identified. The present study was undertaken to determine if one aspect underlying this discrepancy might be a general resistance of the hFSHR to mutation-induced constitutive activity. Five different mutations were introduced into both the hLHR and hFSHR (four based on activating mutations of the hLHR gene, one based on an activating mutation of the hFSHR gene). Our results demonstrate that hFSHR constitutively activating mutants (CAMs) were not as active as hLHR CAMs containing the comparable mutation. …

Evaluating The Roles Of Follicle-Stimulating Hormone Receptor Polymorphisms In Gonadal Hyperstimulation Associated With Severe Juvenile Primary Hypothyroidism, Ginny Ryan, X. Feng, C. D'Alva, M. Zhang, Bradley Van Voorhis, E. Pinto, A. Kubias, S. Antonini, A. Latronico, D. Segaloff

Ginny L. Ryan

CONTEXT: Rare activating mutations of the human (h)FSHR have been reported in some women with spontaneous ovarian hyperstimulation in pregnancy, where follicular growth is inappropriately stimulated by elevated concentrations of human chorionic gonadotropin acting through the hFSHR. It is not known whether ovarian hyperstimulation in peripubertal girls with untreated primary hypothyroidism is caused by hFSHR mutations and/or influenced by hFSHR allelic variants, rendering the hFSHR more sensitive to circulating TSH. OBJECTIVE: The aim of the study was to determine whether mutations of the hFSHR and/or hFSHR allelic variants are associated with greater sensitivity of the hFSHR to TSH. DESIGN: The …

Molecular Analysis Of The Neuropeptide Y1 Receptor Gene In Human Idiopathic Gonadotropin-Dependent Precocious Puberty And Isolated Hypogonadotropic Hypogonadism, K. C. Freitas, Ginny Ryan, V. N. Brito, Y. X. Tao, E. M. Costa, B. B. Mendonca, D. Segaloff, A. C. Latronico

Ginny L. Ryan

OBJECTIVE: To investigate the role of mutations or polymorphisms in the NPY-Y1R gene in human idiopathic central pubertal disorders. DESIGN: Molecular studies. SETTING: University hospital. PATIENT(S): Thirty-three patients with gonadotropin-dependent precocious puberty, 22 with hypogonadotropic hypogonadism, and 50 controls. INTERVENTION(S): Genomic DNA extraction, NPY-Y1R gene sequence analysis, cell-surface expression, and functional activity of an identified receptor variant. MAIN OUTCOME MEASURE(S): Results of sequencing, cell-surface receptor expression, and receptor function. RESULT(S): A heterozygous substitution of lysine (K) by threonine (T) at position 374 in the carboxyl terminal region of NPY-Y1R was identified in a girl with familial GDPP. Her mother, who …

Biological Properties Of A Recombinant Human Immunoglobulin Epsilon-Chain Fragment, T. Ishizaka, B. Helm, J. Hakimi, Jennifer Niebyl, K. Ishizaka, H. Gould

Jennifer R Niebyl

A recombinant human immunoglobulin epsilon-chain gene expression product (rFc epsilon) was compared with a human E myeloma protein in the affinity for epsilon-chain Fc fragment receptors (Fc epsilon R) on cultured human basophils. The association-dissociation kinetics of the rFc epsilon-Fc epsilon R interaction are indistinguishable from that of E myeloma protein, indicating that rFc epsilon and IgE have identical affinity for the receptors. The recombinant gene product sensitizes cultured basophils for anti-IgE-induced histamine release. A dose-response curve of histamine release indicates that the gene product is equally efficient in transducing the signal for degranulation as the natural IgE. Both the …

Morphologic And Immunologic Characterization Of Human Basophils Developed In Cultures Of Cord Blood Mononuclear Cells, T. Ishizaka, A. Dvorak, D. Conrad, Jennifer Niebyl, J. Marquette, K. Ishizaka

Jennifer R Niebyl

Selective growth of human basophilic granulocytes was obtained in suspension cultures of mononuclear cells from umbilical cord blood. Approximately 50 to 80% of nonadherent cells recovered from 2- to 3-wk-old cultures contained metachromatic granules, and these cells were identified as human basophilic granulocytes by electron microscopy. Histamine content of cultured human basophils was comparable to that in peripheral blood basophils. Cultured basophils bear 2.7 to 3.7 X 10(5) IgE receptors per cell that bind both human IgE and rodent IgE with comparable affinity. Average equilibrium constants of the receptors for human IgE and mouse IgE were 2.56 +/- 0.88 X …

The Role Of Indoleamine 2,3-Dioxygenase In Lp-Bpm5 Murine Retroviral Disease Progression, Megan A. O'Connor, William R. Green

Dartmouth Scholarship

Indoleamine 2,3-dioxygenase (IDO) is an immunomodulatory intracellular enzyme involved in tryptophan degradation. IDO is induced during cancer and microbial infections by cytokines, ligation of co-stimulatory molecules and/or activation of pattern recognition receptors, ultimately leading to modulation of the immune response. LP-BM5 murine retroviral infection induces murine AIDS (MAIDS), which is characterized by profound and broad immunosuppression of T- and B-cell responses. Our lab has previously described multiple mechanisms regulating the development of immunodeficiency of LP-BM5-induced disease, including Programmed Death 1 (PD-1), IL-10, and T-regulatory (Treg) cells. Immunosuppressive roles of IDO have been demonstrated in other retroviral models, suggesting a possible …

Role Of Gamma-Aminobutyric Acid Type A (Gabaa) Receptor Subtypes In Acute Benzodiazepine Physical Dependence-Like Effects: Evidence From Squirrel Monkeys Responding Under A Schedule Of Food Presentation., Bradford D Fischer, Laura P Teixeira, Michael L Van Linn, Ojas A Namjoshi, James M Cook, James K Rowlett

Cooper Medical School of Rowan University Faculty Scholarship

RATIONALE: Assays of schedule-controlled responding can be used to characterize the pharmacology of benzodiazepines and other GABAA receptor modulators, and are sensitive to changes in drug effects that are related to physical dependence.

OBJECTIVE: The present study used this approach to investigate the role of GABAA receptor subtypes in mediating dependence-like effects following benzodiazepine administration.

METHODS: Squirrel monkeys (n = 6) were trained on a fixed-ratio schedule of food reinforcement. Initially, the response rate-decreasing effects of chlordiazepoxide (0.1-10 mg/kg; nonselective GABAA receptor agonist), zolpidem (0.032-1.0 mg/kg; α1 subunit-containing GABAA subtype-preferring agonist), and HZ-166 (0.1-10 mg/kg; functionally selective α2 and α3 …

Reinforcing Effects Of Compounds Lacking Intrinsic Efficacy At Α1 Subunit-Containing Gabaa Receptor Subtypes In Midazolam- But Not Cocaine-Experienced Rhesus Monkeys., Nina M Shinday, Eileen K Sawyer, Bradford D Fischer, Donna M Platt, Stephanie C Licata, John R Atack, Gerard R Dawson, David S Reynolds, James K Rowlett

Cooper Medical School of Rowan University Faculty Scholarship

Benzodiazepines are prescribed widely but their utility is limited by unwanted side effects, including abuse potential. The mechanisms underlying the abuse-related effects of benzodiazepines are not well understood, although α1 subunit-containing GABAA receptors have been proposed to have a critical role. Here, we examine the reinforcing effects of several compounds that vary with respect to intrinsic efficacy at α2, α3, and α5 subunit-containing GABAA receptors but lack efficacy at α1 subunit-containing GABAA receptors ('α1-sparing compounds'): MRK-623 (functional selectivity for α2/α3 subunit-containing receptors), TPA023B (functional selectivity for α2/α3/α5 subunit-containing receptors), and TP003 (functional selectivity for α3 subunit-containing receptors). The reinforcing effects …

Diagnostic-Specific Reductions In Nmda And Mglu5 Glutamatergic Receptors In Schizophrenia, K Newell, N Jimenez, A Geddes, E Frank, T Du Bois, M Safadi, Xu-Feng Huang

Xu-Feng Huang

Abstract of a paper that presented at the Australian Neuroscience Society 32nd Annual meeting

Androgens Upregulate Cdc25c Protein By Inhibiting Its Proteasomal And Lysosomal Degradation Pathways., Yu-Wei Chou, Li Zhang, Sakthivel Muniyan, Humera Ahmad, Satyendra Kumar, Syed Mahfuzul Alam, Ming-Fong Lin

Journal Articles: Biochemistry & Molecular Biology

Cdc25C is a cell cycle protein of the dual specificity phosphatase family essential for activating the cdk1/Cyclin B1 complex in cells entering into mitosis. Since altered cell cycle is a hallmark of human cancers, we investigated androgen regulation of Cdc25C protein in human prostate cancer (PCa) cells, including androgen-sensitive (AS) LNCaP C-33 cells and androgen-independent (AI) LNCaP C-81 as well as PC-3 cells. In the regular culture condition containing fetal bovine serum (FBS), Cdc25C protein levels were similar in these PCa cells. In a steroid-reduced condition, Cdc25C protein was greatly decreased in AS C-33 cells but not AI C-81 or …

Estradiol Reduces Susceptibility Of Cd4+ T Cells And Macrophages To Hiv-Infection, Marta Rodriguez-Garcia, Nabanita Biswas, Mickey V. Patel, Fiona D. Barr, Sarah G. Christ, Chrsitina Ochsenbauer, John V. Fahey, Charles R. Wira

Dartmouth Scholarship

The magnitude of the HIV epidemic in women requires urgent efforts to find effective preventive methods. Even though sex hormones have been described to influence HIV infection in epidemiological studies and regulate different immune responses that may affect HIV infection, the direct role that female sex hormones play in altering the susceptibility of target cells to HIV-infection is largely unknown. Here we evaluated the direct effect of 17-b-estradiol (E₂) and ethinyl estradiol (EE) in HIV-infection of CD4⁺ T-cells and macrophages. Purified CD4⁺ T-cells and monocyte-derived macrophages were generated in vitro from peripheral blood and infected with …

Immunomodulatory And Transcriptional Effects Of Progesterone Through Progesterone A And B Receptors In Hec50co Poorly Differentiated Endometrial Cancer Cells, S. Davies, Donghai Dai, D. Wolf, Kimberly Leslie

Donghai Dai

OBJECTIVE: Derivatives of progesterone, progestins, are used to treat endometrial cancer; however, the pathways activated by the hormone have not been fully investigated. Progesterone acts through two receptor isoforms, progesterone receptors A and B (PRA and PRB), transcription factors that control the expression of downstream genes leading to endometrial differentiation. The purpose of this study was to perform an expression analysis to identify the mechanisms underlying progesterone's growth suppressive and immunomodulatory effects in endometrial cancer. METHODS: To study the molecular effects of progesterone, PRs were introduced into Hec50co cells. Expression array analyses followed by confirmatory semiquantitive reverse-transcriptase polymerase chain reaction …