Other Pharmacy and Pharmaceutical Sciences Commons^™

A V-To-F Substitution In Sk2 Channels Causes Ca2+ Hypersensitivity And Improves Locomotion In A C. Elegans Als Model, Young-Woo Nam, Sabia N. Baskoylu, Dimitris Gazgalis, Razan Orfali, Meng Cui, Anne C. Hart, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca2+-activated K+ (SK) channels mediate medium afterhyperpolarization in the neurons and play a key role in the regulation of neuronal excitability. SK channels are potential drug targets for ataxia and Amyotrophic Lateral Sclerosis (ALS). SK channels are activated exclusively by the Ca2+-bound calmodulin. Previously, we identified an intrinsically disordered fragment that is essential for the mechanical coupling between Ca2+/calmodulin binding and channel opening. Here, we report that substitution of a valine to phenylalanine (V407F) in the intrinsically disordered fragment caused a ~6 fold increase in the Ca2+ sensitivity of SK2-a channels. This substitution resulted in a novel interaction between …

Design, Synthesis, And Evaluation Of Homochiral Peptides Containing Arginine And Histidine As Molecular Transporters, Naglaa Salem El-Sayed, Taryn Miyake, Amir Nasrolahi Shirazi, Shang Eun Park, Jimmy Clark, Stephani Buchholz, Keykavous Parang, Rakesh Tiwari

Pharmacy Faculty Articles and Research

Linear (HR)n and cyclic [HR]n peptides (n = 4,5) containing alternate arginine and histidine residues were synthesized. The peptides showed 0–15% cytotoxicity at 5–100 μM in human ovarian adenocarcinoma (SK-OV-3) cells while they exhibited 0–12% toxicity in human leukemia cancer cell line (CCRF-CEM). Among all peptides, cyclic [HR]4 peptide was able to improve the delivery of a cell impermeable fluorescence-labeled phosphopeptide by two-fold. Fatty acids of different alkyl chain length were attached at the N-terminal of the linear peptide (HR)4 to improve the molecular transporter property. Addition of fatty acyl chains was expected to help with the permeation of the …

Efficient Intracellular Delivery Of Cell-Impermeable Cargo Molecules By Peptides Containing Tryptophan And Histidine, Amir Nasrolahi Shirazi, Saghar Mozaffari, Rinzhin Tshering Sherpa, Rakesh Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

We have previously evaluated and reported numerous classes of linear and cyclic peptides containing hydrophobic and hydrophilic segments for intracellular delivery of multiple molecular cargos. Herein, a combination of histidine and tryptophan amino acids were designed and evaluated for their efficiency in intracellular delivery of cell-impermeable phosphopeptides and the anti-HIV drug, emtricitabine. Two new decapeptides, with linear and cyclic natures, both containing alternate tryptophan and histidine residues, were synthesized using Fmoc/tBu solid-phase chemistry. The peptides were characterized and purified by using matrix-assisted laser desorption/ionization (MALDI) spectroscopy and high-performance liquid chromatography (HPLC), respectively. These peptides did not show significant toxicity up …

Synthesis, Characterization, And In Vitro Cytotoxicity Of Fatty Acyl-Cgkrk-Chitosan Oligosaccharides Conjugates For Sirna Delivery, Naglaa Salem El-Sayed, Meenakshi Sharma, Hamidreza Montazeri Aliabadi, Magda Goda El-Meligy, Ahmed Kamed El-Zaity, Zenat Adeeb Nageib, Rakesh Tiwari

Pharmacy Faculty Articles and Research

In this studies, three fatty acyl derivatives of CGKRK homing peptides were coupled successfully to chitosan oligosaccharides (COS) using sulfosuccinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate sodium salt (sulfo-SMCC). The COS-SMCC was prepared by direct coupling between COS and sulfo-SMCC in PBS (pH 7.5) at RT for 48 h. The structure of COS-SMCC and the three fatty acyl-CGKRK-SMCC-COS conjugates were characterized by FT-IR, ¹³C NMR, and SEM. The ability of three conjugates to condense siRNA into nanosized polyplexes and their efficacy in protecting siRNA from serum nucleases degradation were investigated. Among the investigated derivatives, S-CGKRK-COS showed higher siRNA binding affinity as compared to …

The Effect Of Grapefruit Intake On Endogenous Serum Estrogen Levels In Postmenopausal Women, Kristine R. Monroe, Frank Z. Stanczyk, Kathleen Hill-Besinque, Malcolm C. Pike

Pharmacy Faculty Articles and Research

Although grapefruit intake leads to elevated serum estrogen levels when hormones are taken orally, there are no published data on the effect on endogenous levels. We conducted a pilot dietary intervention study among healthy postmenopausal volunteers to test whole grapefruit, 2 juices, and 1 grapefruit soda. Fifty-nine participants were recruited through the Love/Avon Army of Women. The study consisted of a 3-wk run-in, 2 wk of grapefruit intake, and a 1-wk wash-out. Eight fasting blood samples were collected. An additional 5 samples drawn at 1, 2, 4, 8, and 10 hr after grapefruit intake were collected during an acute-phase study …

Design And Evaluation Of Gemini Surfactant-Based Lipoplexes Modified With Cell-Binding Peptide For Targeted Gene Therapy, Waleed Mohammed-Saeid, Rania Soudy, Richa Tikoo, Kamaljit Kaur, Ronald E. Verrall, Ildiko Badea

Pharmacy Faculty Articles and Research

Purpose Achieving successful gene therapy requires delivery of a gene vector specifically to the targeted tissue with efficient expression and a good safety profile. The objective of this work was to develop, characterize and determine if a novel gemini surfactant-based lipoplex systems, modified with a cancer-targeting peptide p18-4, could serve this role. Methods The targeting peptide p18-4 was either chemically coupled to a gemini surfactant backbone or physically co-formulated with the lipoplexes. The influence of targeting ligand and formulation strategies on essential physicochemical properties of the lipoplexes was evaluated by dynamic light scattering and small angle X-ray scattering techniques. In …

Pde8 Is Expressed In Human Airway Smooth Muscle And Selectively Regulates Camp Signaling By Β 2 Ar-Ac6, Timothy B. Johnstone, Kaitlyn H. Smith, Cynthia J. Koziol-White, Fengying Li, Austin G. Kazarian, Maia L. Corpuz, Maya Shumyachter, Frederick J. Ehlert, Bianca E. Himes, Reynold A. Pannettieri Jr., Rennolds S. Ostrom

Pharmacy Faculty Articles and Research

Two cAMP signaling compartments centering around adenylyl cyclase (AC) exist in human airway smooth muscle (HASM) cells, one containing ß2AR-AC6 and another containing E prostanoid receptors (EPR)-AC2. We hypothesized that different phosphodiesterase (PDE) isozymes selectively regulate cAMP signaling in each compartment. According to RNA-seq data, 18 of 24 PDE genes were expressed in primary HASM cells derived from age- and gender-matched donors with and without asthma. PDE8A was the third most abundant of the cAMP-degrading PDE genes, after PDE4A and PDE1A. Knockdown of PDE8A using shRNA evoked 2-fold greater cAMP responses to 1 DM forskolin in the presence of IBMX. …

Structural Insights Into The Potency Of Sk Channel Positive Modulators, Young-Woo Nam, Razan Orfali, Tingting Liu, Kunqian Yu, Meng Cui, Heike Wulff, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca2+-activated K+ (SK) channels play essential roles in the regulation of cellular excitability and have been implicated in neurological and cardiovascular diseases through both animal model studies and human genetic association studies. Over the past two decades, positive modulators of SK channels such as NS309 and 1-EBIO have been developed. Our previous structural studies have identified the binding pocket of 1-EBIO and NS309 that is located at the interface between the channel and calmodulin. In this study, we took advantage of four compounds with potencies varying over three orders of magnitude, including 1-EBIO, NS309, SKS-11 (6-bromo-5-methyl-1H-indole-2,3-dione-3-oxime) and …

Cyclic Peptide Conjugate Of Curcumin And Doxorubicin As An Anticancer Agent, Shaban Darwish, Saghar Mozaffari, Keykavous Parang, Rakesh Tiwari

Pharmacy Faculty Articles and Research

The hydrophobicity of curcumin creates hurdle towards its use in the anticancer therapy. Herein, we synthesized a curcumin-doxorubicin conjugated cyclic peptide scaffold to improve the solubility of curcumin and create a conjugate containing two anticancer agents. A solid-phase Fmoc/tBu solid phase methodology was used to synthesize a cell-penetrating nuclear targeting peptide with free thiol and amine groups, which was coupled with the activated doxorubicin (Dox) and curcumin, affording Dox-peptide-curcumin conjugate (DPCC) (10). The antiproliferative activity of the conjugate was evaluated in human leukemia carcinoma cell (CCRF-CEM), human ovarian carcinoma cell (SKOV-3), and normal kidney cell line (LLCPK). Cyclic peptide-doxorubicin conjugate …

Tumor-Targeted Delivery Of Sirna Using Fatty Acyl-Cgkrk Peptide Conjugates, Meenakshi Sharma, Naglaa Salem El-Sayed, Hung Do, Keykavous Parang, Rakesh Tiwari, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

Tumor-targeted carriers provide efficient delivery of chemotherapeutic agents to tumor tissue. CGKRK is one of the well-known tumor targeting peptides with significant specificity for angiogenic blood vessels and tumor cells. Here, we designed fatty acyl conjugated CGKRK peptides, based on the hypothesis that hydrophobically-modified CGKRK peptide could enhance cellular permeation and delivery of siRNA targeted to tumor cells for effective silencing of selected proteins. We synthesized six fatty acyl-peptide conjugates, using a diverse chain of saturated and unsaturated fatty acids to study the efficiency of this approach. At peptide:siRNA weight/weight ratio of 10:1 (N/P ≈ 13.6), almost all the peptides …

Compartmentalized Camp Responses To Prostaglandin Ep2 Receptor Activation In Human Airway Smooth Muscle Cells, Shailesh R. Agarwal, Kathryn Miyashiro, Htun Latt, Rennolds S. Ostrom, Robert D. Harvey

Pharmacy Faculty Articles and Research

Background and Purpose

Previous studies indicate that prostaglandin EP2 receptors (EP2Rs) selectively couple to adenylyl cyclase type 2 (AC2) in non-lipid raft domains of airway smooth muscle (ASM) cells, where they regulate specific cAMP-dependent responses. The goal of the present study was to identify the cellular microdomains where EP2Rs stimulate cAMP production.

Experimental Approach

FRET-based cAMP biosensors were targeted to different subcellular locations of primary human ASM cells. The Epac2-camps biosensor, which expresses throughout the cell, was used to measure bulk cytoplasmic responses. Epac2-MyrPalm and Epac2-CAAX were used to measure responses associated with lipid raft and non-raft regions of the …

Identification Of A Nucleoside Analog Active Against Adenosine Kinase-Expressing Plasma Cell Malignancies, Utthara Nayar, Jouliana Sadek, Jonathan Reichel, Denise Hernandez-Hopkins, Gunkut Akar, Peter J. Barelli, Michelle A. Sahai, Hufeng Zhou, Jennifer Totonchy, David Jayabalan, Ruben Niesvizky, Ilaria Guasparri, Duane Hassane, Yifang Liu, Shizuko Sei, Robert H. Shoemaker, J. David Warren, Olivier Elemento, Kenneth M. Kaye, Ethel Cesarman

Pharmacy Faculty Articles and Research

Primary effusion lymphoma (PEL) is a largely incurable malignancy of B cell origin with plasmacytic differentiation. Here, we report the identification of a highly effective inhibitor of PEL. This compound, 6-ethylthioinosine (6-ETI), is a nucleoside analog with toxicity to PEL in vitro and in vivo, but not to other lymphoma cell lines tested. We developed and performed resistome analysis, an unbiased approach based on RNA sequencing of resistant subclones, to discover the molecular mechanisms of sensitivity. We found different adenosine kinase–inactivating (ADK-inactivating) alterations in all resistant clones and determined that ADK is required to phosphorylate and activate 6-ETI. Further, we …

Activity Of Distinct Growth Factor Receptor Network Components In Breast Tumors Uncovers Two Biologically Relevant Subtypes, Moom Roosan, Shelley M. Macneil, David F. Jenkins, Gajendra Shrestha, Sydney R. Wyatt, Jasmine A. Mcquerry, Stephen R. Piccolo, Laura M. Heiser, Joe W. Gray, W. Evan Johnson, Andrea H. Bild

Pharmacy Faculty Articles and Research

Background
The growth factor receptor network (GFRN) plays a significant role in driving key oncogenic processes. However, assessment of global GFRN activity is challenging due to complex crosstalk among GFRN components, or pathways, and the inability to study complex signaling networks in patient tumors. Here, pathway-specific genomic signatures were used to interrogate GFRN activity in breast tumors and the consequent phenotypic impact of GRFN activity patterns.

Methods
Novel pathway signatures were generated in human primary mammary epithelial cells by overexpressing key genes from GFRN pathways (HER2, IGF1R, AKT1, EGFR, KRAS (G12V), RAF1, BAD). The pathway analysis toolkit Adaptive Signature Selection …

Engineered Peptides For Applications In Cancer-Targeted Drug Delivery And Tumor Detection, R. Soudy, N. Byeon, Y. Raghuwanshi, S. Ahmed, A. Lavasanifar, Kamaljit Kaur

Pharmacy Faculty Articles and Research

Cancer-targeting peptides as ligands for targeted delivery of anticancer drugs or drug carriers have the potential to significantly enhance the selectivity and the therapeutic benefit of current chemotherapeutic agents. Identification of tumor-specific biomarkers like integrins, aminopeptidase N, and epidermal growth factor receptor as well as the popularity of phage display techniques along with synthetic combinatorial methods used for peptide design and structure optimization have fueled the advancement and application of peptide ligands for targeted drug delivery and tumor detection in cancer treatment, detection and guided therapy. Although considerable preclinical data have shown remarkable success in the use of tumor targeting …

Identification Of Potential Drug Targets In Cancer Signaling Pathways Using Stochastic Logical Models, Peican Zhu, Hamidreza Montazeri Aliabadi, Hasan Uludag, Jie Han

Pharmacy Faculty Articles and Research

The investigation of vulnerable components in a signaling pathway can contribute to development of drug therapy addressing aberrations in that pathway. Here, an original signaling pathway is derived from the published literature on breast cancer models. New stochastic logical models are then developed to analyze the vulnerability of the components in multiple signalling sub-pathways involved in this signaling cascade. The computational results are consistent with the experimental results, where the selected proteins were silenced using specific siRNAs and the viability of the cells were analyzed 72 hours after silencing. The genes elF4E and NFkB are found to have nearly no …

Design, Synthesis, And Evaluation Of Chitosan Conjugated Ggrgdsk Peptides As A Cancer Cell-Targeting Molecular Transporter, Naglaa Salem El-Sayed, Amir Nasrolahi Shirazi, Magda Goda El-Meligy, Ahmed Kamel El-Ziaty, Zenat A. Nagieb, Keykavous Parang, Rakesh Tiwari

Pharmacy Faculty Articles and Research

Targeting cancer cells using integrin receptor is one of the promising targeting strategies in drug delivery. In this study, we conjugated an integrin-binding ligand (GGRGDSK) peptide to chitosan oligosaccharide (COS) using (sulfo-SMCC) bifunctional linker affording COS-SMCC-GGRGDSK. The conjugated polymer was characterized by FT-IR, ¹H NMR, ¹³C NMR, and SEM. COS-SMCC-GGRGDSK did not show cytotoxicity up to a concentration of 1 mg/mL in the human leukemia cell line (CCRF-CEM). The conjugate was evaluated for its ability to enhance the cellular uptake of cell-impermeable cargoes (e.g., FAM and F′-G(pY)EEI phosphopeptide) in CCRF-CEM, and human ovarian carcinoma (SK-OV-3) cancer …

Elucidating Proteasome Catalytic Subunit Composition And Its Role In Proteasome Inhibitor Resistance, Kimberly C. Carmony

Theses and Dissertations--Pharmacy

Proteasome inhibitors bortezomib and carfilzomib are FDA-approved anticancer agents that have contributed to significant improvements in treatment outcomes. However, the eventual onset of acquired resistance continues to limit their clinical utility, yet a clear consensus regarding the underlying mechanisms has not been reached.

Bortezomib and carfilzomib are known to target both the constitutive proteasome and the immunoproteasome, two conventional proteasome subtypes comprising distinctive sets of catalytic subunits. While it has become increasingly evident that additional, ‘intermediate’ proteasome subtypes, which harbor non-standard mixtures of constitutive proteasome and immunoproteasome catalytic subunits, represent a considerable proportion of the proteasome population in many cell …

Kaposi Sarcoma Herpesvirus Induces Ho-1 During De Novo Infection Of Endothelial Cells Via Viral Mirna-Dependent And -Independent Mechanisms, Sara Botto, Jennifer Totonchy, Jean K. Gustin, Ashlee V. Moses

Pharmacy Faculty Articles and Research

Kaposi sarcoma (KS) herpesvirus (KSHV) infection of endothelial cells (EC) is associated with strong induction of heme oxygenase-1 (HO-1), a stress-inducible host gene that encodes the rate-limiting enzyme responsible for heme catabolism. KS is an angioproliferative tumor characterized by the proliferation of KSHV-infected spindle cells, and HO-1 is highly expressed in such cells. HO-1 converts the pro-oxidant, proinflammatory heme molecule into metabolites with antioxidant, antiinflammatory, and proliferative activities. Previously published work has shown that KSHV-infected EC in vitro proliferate in response to free heme in a HO-1-dependent manner, thus implicating virus-enhanced HO-1 activity in KS tumorigenesis. The present study investigated …

Non-Raft Ac2 Defines A Camp Signaling Compartment That Selectively Regulates Il-6 Expression In Airway Smooth Muscle Cells, Amy S. Bogard, Anna V. Birg, Rennolds S. Ostrom

Pharmacy Faculty Articles and Research

Adenylyl cyclase (AC) isoforms differ in their tissue distribution, cellular localization, regulation, and protein interactions. Most cell types express multiple AC isoforms. We hypothesized that cAMP produced by different AC isoforms regulates unique cellular responses in human bronchial smooth muscle cells (BSMC). Overexpression of AC2, AC3, or AC6 had distinct effects on forskolin (Fsk)-induced expression of a number of known cAMP-responsive genes. These data show that different AC isoforms can differentially regulate gene expression. Most notable, overexpression and activation of AC2 enhanced interleukin 6 (IL-6) expression, but overexpression of AC3 or AC6 had no effect. IL-6 production by BSMC was …

Aberrant Proliferation In Cxcr7+ Endothelial Cells Via Degradation Of The Retinoblastoma Protein, Jennifer Totonchy, Jessica M. Osborn, Sara Botto, Lisa Clepper, Ashlee V. Moses

Pharmacy Faculty Articles and Research

Angiogenesis is a critical factor in the growth and dissemination of solid tumors. Indeed, tumor vasculature is abnormal and contributes to the development and spread of malignancies by creating a hostile microenvironment. The alternative SDF-1/CXCL12 receptor, CXCR7, is frequently and specifically expressed in tumor-associated vessels. In this study, we examine the role of endothelium-expressed CXCR7 in tumor vascular dysfunction by specifically examining the contribution of CXCR7 to endothelial cell (EC) proliferation. We demonstrate that CXCR7 expression is sufficient to drive post-confluent growth in EC cultures. Further, we provide a novel mechanism for CXCR7-mediated proliferation via proteasomal degradation of the tumor …

Menthol Binding And Inhibition Of A7-Nicotinic Acetylcholine Receptors, Abrar Ashoor, Jacob C. Nordman, Daniel Veltri, Keun-Hang Susan Yang, Lina T. Al Kury, Yaroslav M. Shuba, Mohamed Magoub, Frank Christopher Howarth, Bassem Sadek, Amarda Shehu, Nadine Kabbani, Murat Oz

Mathematics, Physics, and Computer Science Faculty Articles and Research

Menthol is a common compound in pharmaceutical and commercial products and a popular additive to cigarettes. The molecular targets of menthol remain poorly defined. In this study we show an effect of menthol on the α7 subunit of the nicotinic acetylcholine (nACh) receptor function. Using a two-electrode voltage-clamp technique, menthol was found to reversibly inhibit α7-nACh receptors heterologously expressed in Xenopus oocytes. Inhibition by menthol was not dependent on the membrane potential and did not involve endogenous Ca2+-dependent Cl− channels, since menthol inhibition remained unchanged by intracellular injection of the Ca2+ chelator BAPTA and perfusion with Ca2+-free bathing solution containing …

Melatonin Membrane Receptors In Peripheral Tissues: Distribution And Functions, Radomir M. Slominski, Russel J. Reiter, Natalia Schlabritz-Loutsevich, Rennolds S. Ostrom, Andrzej T. Slominski

Pharmacy Faculty Articles and Research

Many of melatonin’s actions are mediated through interaction with the G-protein coupled membrane bound melatonin receptors type 1 and type 2 (MT1 and MT2, respectively) or, indirectly with nuclear orphan receptors from the RORα/RZR family. Melatonin also binds to the quinone reductase II enzyme, previously defined the MT3 receptor. Melatonin receptors are widely distributed in the body; herein we summarize their expression and actions in non-neural tissues. Several controversies still exist regarding, for example, whether melatonin binds the RORα/RZR family. Studies of the peripheral distribution of melatonin receptors are important since they are attractive targets for immunomodulation, regulation of endocrine, …

Choreographing The Adenylyl Cyclase Signalosome: Sorting Out The Partners And The Steps, Rennolds S. Ostrom, Amy S. Bogard, Robert Gros

Pharmacy Faculty Articles and Research

Adenylyl cyclases are a ubiquitous family of enzymes and are critical regulators of metabolic and cardiovascular function. Multiple isoforms of the enzyme are expressed in a range of tissues. However, for many processes, the adenylyl cyclase isoforms have been thought of as essentially interchangeable, with their impact more dependent on their common actions to increase intracellular cyclic adenosine monophosphate content regardless of the isoform involved. It has long been appreciated that each subfamily of isoforms demonstrate a specific pattern of “upstream” regulation, i.e., specific patterns of ion dependence (e.g., calcium-dependence) and specific patterns of regulation by kinases (protein kinase A …

Kshv Infection Of Endothelial Cells Manipulates Cxcr7-Mediated Signaling: Implications For Kaposi’S Sarcoma Progression And Intervention, Jennifer Totonchy, Lisa Clepper, Janet Douglas, Liron Pantanowitz, Klaus Fruh, Ashlee V. Moses

Pharmacy Faculty Articles and Research

"CXCR7 was recently characterized as an alternative receptor for the chemokine CXCL12/SDF-1, previously thought to bind and signal exclusively through CXCR4.We recently identified CXCR7 as a key cellular factor in the endothelial cell (EC) dysfunction associated with KSHV infection. CXCL12 signaling is critically associated with tumor growth, angiogenesis and metastasis in several diverse tumors and is one of the most studied chemokine/chemokine receptor interactions in cancer systems. The tumorigenic activity of the CXCL12 signaling axis offers an attractive target for therapeutic intervention in multiple cancers including Kaposi’s Sarcoma (KS). However, most of the research to date was based on the …

Impaired M3 And Enhanced M2 Muscarinic Receptor Contractile Function In A Streptozotocin Model Of Mouse Diabetic Urinary Bladder, K. J. Pak, Rennolds S. Ostrom, M. Matsui, F. J. Ehlert

Pharmacy Faculty Articles and Research

We investigated the contractile roles of M2 and M3 muscarinic receptors in urinary bladder from streptozotocin-treated mice. Wild-type and M2 muscarinic receptor knockout (M2 KO) mice were given a single injection of vehicle or streptozotocin (125 mg kg−1) 2–24 weeks prior to bladder assays. The effect of forskolin on contractions elicited to the muscarinic agonist, oxotremorine-M, was measured in isolated urinary bladder (intact or denuded of urothelium). Denuded urinary bladder from vehicle-treated wild-type and M2 KO mice exhibited similar contractile responses to oxotremorine-M, when contraction was normalized relative to that elicited by KCl (50 mM). Eight to 9 weeks after …

The Guinea Pig Ileum Lacks The Direct, High-Potency, M2-Muscarinic, Contractile Mechanism Of The Mouse Ileum, Michael T. Griffin, Minoru Matsui, Rennolds S. Ostrom, Frederick J. Ehlert

Pharmacy Faculty Articles and Research

We explored whether the M2 muscarinic receptor in the guinea pig ileum elicits a highly potent, direct-contractile response, like that from the M3 muscarinic receptor knockout mouse. First, we characterized the irreversible receptor-blocking activity of 4-DAMP mustard in ileum from muscarinic receptor knockout mice to verify its M3 selectivity. Then, we used 4-DAMP mustard to inactivate M3 responses in the guinea pig ileum to attempt to reveal direct, M2 receptor-mediated contractions. The muscarinic agonist, oxotremorine-M, elicited potent contractions in ileum from wild-type, M2 receptor knockout, and M3 receptor knockout mice characterized by negative log EC50 (pEC50) values ± SEM of …

The C1 And C2 Domains Target Human Type 6 Adenylyl Cyclase To Lipid Rafts And Caveolae, Muthusamy Thangavel, Xiaoqiu Liu, Shu Qiang Sun, Joseph Kaminsky, Rennolds S. Ostrom

Pharmacy Faculty Articles and Research

Previous data has shown that adenylyl cyclase type 6 (AC6) is expressed principally in lipid rafts or caveolae of cardiac myocytes and other cell types while certain other isoforms of AC are excluded from these microdomains. The mechanism by which AC6 is localized to lipid rafts or caveolae is unknown. In this study, we show AC6 is localized in lipid rafts of COS-7 cells (expressing caveolin-1) and in HEK-293 cells or cardiac fibroblasts isolated from caveolin-1 knock-out mice (both of which lack prototypical caveolins). To determine the region of AC6 that confers raft localization, we independently expressed each of the …

Adenylyl Cyclase Type 6 Overexpression Selectively Enhances Ss-Adrenergic And Prostacyclin Receptor Mediated Inhibition Of Rat Cardiac Fibroblast Function Due To Co-Localization In Lipid Rafts, Xiaoqiu Liu, Muthusamy Thangavel, Shu Qiang Sun, Joseph Kaminsky, Penden Mahautmr, Jeremiah Stitham, John Hwa, Rennolds S. Ostrom

Pharmacy Faculty Articles and Research

Cardiac fibroblasts produce and degrade extracellular matrix and are critical in regulating cardiac remodeling and hypertrophy. Fibroblasts are activated by factors such as transforming growth factor β and inhibited by agents that elevate 3′,5′-cyclic adenosine monophosphate (cAMP) levels. cAMP signal generation and response is known to be compartmentalized in many cell types in part through the colocalization of receptors and specific adenylyl cyclase isoforms in lipid rafts and caveolae. The present study sought to define the localization of key G protein-coupled receptors with adenylyl cyclase type 6 (AC6) in lipid rafts of rat cardiac fibroblasts and to determine if this …

Methods For The Study Of Signaling Molecules In Membrane Lipid Rafts And Caveolae, Rennolds S. Ostrom, Paul A. Insel

Pharmacy Faculty Articles and Research

Lipid rafts and caveolae are cholesterol- and sphingolipid-rich microdomains of the plasma membrane that concentrate components of certain signal transduction pathways. Interest in and exploration of these microdomains has grown in recent years, especially after the discovery of the biochemical marker of caveolae, caveolin, and the recognition that caveolin interacts with many different signaling molecules via its scaffolding domain. There are three major types of caveolins (1, 2, and 3), with some selectivity in their expression in different tissues. Results assessing lipid raft/caveolae co-localization of molecules in signal transduction pathways have provided support for the idea that signaling components are …

Nitric Oxide Inhibition Of Adenylyl Cyclase Type 6 Activity Is Dependent Upon Lipid Rafts And Caveolin Signaling Complexes, Rennolds S. Ostrom, Richard A. Bundey, Paul A. Insel

Pharmacy Faculty Articles and Research

Several cell types, including cardiac myocytes and vascular endothelial cells, produce nitric oxide (NO) via both constitutive and inducible isoforms of NO synthase. NO attenuates cardiac contractility and contributes to contractile dysfunction in heart failure, although the precise molecular mechanisms for these effects are poorly defined. Adenylyl cyclase (AC) isoforms type 5 and 6, which are preferentially expressed in cardiac myocytes, may be inhibited via a direct nitrosylation by NO. Because endothelial NO synthase (eNOS and NOS3), β-adrenergic ( AR) receptors, and AC6 all can localize in lipid raft/caveolin-rich microdomains, we sought to understand the role of lipid rafts in …