Cells Commons^™

Oxidative Stress And Ion Channels In Neurodegenerative Diseases, Razan Orfali, Adnan Z. Alwatban, Rawan S. Orfali, Liz Lau, Noble Chea, Abdullah M. Alotaibi, Young-Woo Nam, Miao Zhang

Pharmacy Faculty Articles and Research

Numerous neurodegenerative diseases result from altered ion channel function and mutations. The intracellular redox status can significantly alter the gating characteristics of ion channels. Abundant neurodegenerative diseases associated with oxidative stress have been documented, including Parkinson’s, Alzheimer’s, spinocerebellar ataxia, amyotrophic lateral sclerosis, and Huntington’s disease. Reactive oxygen and nitrogen species compounds trigger posttranslational alterations that target specific sites within the subunits responsible for channel assembly. These alterations include the adjustment of cysteine residues through redox reactions induced by reactive oxygen species (ROS), nitration, and S-nitrosylation assisted by nitric oxide of tyrosine residues through peroxynitrite. Several ion channels have been directly …

Primary Cilium-Dependent Signaling Mechanisms, Rajasekharreddy Pala, Nedaa Alomari, Surya M. Nauli

Pharmacy Faculty Articles and Research

Primary cilia are hair-like organelles and play crucial roles in vertebrate development, organogenesis, health, and many genetic disorders. A primary cilium is a mechano-sensory organelle that responds to mechanical stimuli in the micro-environment. A cilium is also a chemosensor that senses chemical signals surrounding a cell. The overall function of a cilium is therefore to act as a communication hub to transfer extracellular signals into intracellular responses. Although intracellular calcium has been one of the most studied signaling messengers that transmit extracellular signals into the cells, calcium signaling by various ion channels remains a topic of interest in the field. …

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 …

Inhibition Of Human Α7 Nicotinic Acetylcholine Receptors By Cyclic Monoterpene Carveol, Yusra Lozon, Ahmed Sultan, Stuart J. Lansdell, Tatiana Prytkova, Bassem Sadek, Keun-Hang Susan Yang, Frank Christopher Howarth, Neil S. Millar, Murat Oz

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Cyclic monoterpenes are a group of phytochemicals with antinociceptive, local anesthetic, and anti-inflammatory actions. Effects of cyclic monoterpenes including vanilin, pulegone, eugenole, carvone, carvacrol, carveol, thymol, thymoquinone, menthone, and limonene were investigated on the functional properties of the cloned α₇ subunit of the human nicotinic acetylcholine receptor expressed in Xenopus oocytes. Monoterpenes inhibited the α₇ nicotinic acetylcholine receptor in the order carveol>thymoquinone>carvacrol>menthone>thymol>limonene>eugenole>pulegone≥carvone≥vanilin. Among the monoterpenes, carveol showed the highest potency on acetylcholine-induced responses, with IC₅₀ of 8.3 µM. Carveol-induced inhibition was independent of the membrane potential and could not be …

Better Cognitive Control Of Emotional Information Is Associated With Reduced Pro-Inflammatory Cytokine Reactivity To Emotional Stress, Grant S. Shields, Shari Young Kuchenbecker, Sarah D. Pressman, Ken D. Sumida, George M. Slavich

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Stress is strongly associated with several mental and physical health problems that involve inflammation, including asthma, cardiovascular disease, certain types of cancer, and depression. It has been hypothesized that better cognitive control of emotional information may lead to reduced inflammatory reactivity to stress and thus better health, but to date no studies have examined whether differences in cognitive control predict pro-inflammatory cytokine responses to stress. To address this issue, we conducted a laboratory-based experimental study in which we randomly assigned healthy young-adult females to either an acute emotional stress (emotionally evocative video) or no-stress (control video) condition. Salivary levels of …

Chemical-Free Technique To Study The Ultrastructure Of Primary Cilium, Ashraf M. Mohieldin, Wissam A. Aboualaiwi, Min Gao, Surya M. Nauli

Pharmacy Faculty Articles and Research

A primary cilium is a hair-like structure with a width of approximately 200 nm. Over the past few decades, the main challenge in the study of the ultrastructure of cilia has been the high sensitivity of cilia to chemical fixation, which is required for many imaging techniques. In this report, we demonstrate a combined high-pressure freezing (HPF) and freeze-fracture transmission electron microscopy (FFTEM) technique to examine the ultrastructure of a cilium. Our objective is to develop an optimal high-resolution imaging approach that preserves cilia structures in their best natural form without alteration of cilia morphology by chemical fixation interference. Our …

Protein Composition And Movements Of Membrane Swellings Associated With Primary Cilia, Ashraf M. Mohieldin, Hanan S. Haymour, Shao T. Lo, Wissam A. Aboualaiwi, Kimberly F. Atkinson, Christopher J. Ward, Min Gao, Oliver Wessely, Surya M. Nauli

Pharmacy Faculty Articles and Research

Dysfunction of many ciliary proteins has been linked to a list of diseases, from cystic kidney to obesity and from hypertension to mental retardation. We previously proposed that primary cilia are unique communication organelles that function as microsensory compartments that house mechanosensory molecules. Here we report that primary cilia exhibit membrane swellings, which based on their unique ultrastructure and motility, could be mechanically regulated by fluid-shear stress. Together with the ultrastructure analysis of the bulb, which contains monosialodihexosylganglioside (GM3), our results show that ciliary membrane swelling has a distinctive set of functional proteins, including GM3 synthase (GM3S), bicaudal-c1 (Bicc1) and …

Structure-Based Network Analysis Of Activation Mechanisms In The Erbb Family Of Receptor Tyrosine Kinases: The Regulatory Spine Residues Are Global Mediators Of Structural Stability And Allosteric Interactions, Kevin A. James, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

The ErbB protein tyrosine kinases are among the most important cell signaling families and mutation-induced modulation of their activity is associated with diverse functions in biological networks and human disease. We have combined molecular dynamics simulations of the ErbB kinases with the protein structure network modeling to characterize the reorganization of the residue interaction networks during conformational equilibrium changes in the normal and oncogenic forms. Structural stability and network analyses have identified local communities integrated around high centrality sites that correspond to the regulatory spine residues. This analysis has provided a quantitative insight to the mechanism of mutation-induced ‘‘superacceptor’’ activity …

Chylomicrons Produced By Caco-2 Cells Contained Apob-48 With Diameter Of 80-200 Nm, Andromeda M. Nauli, Yuxi Sun, Judy D. Whittimore, Seif Atyia, Guha Krishnaswamy, Surya M. Nauli

Pharmacy Faculty Articles and Research

The small intestine generally transports dietary fats to circulation in triglyceride (TG)-rich lipoproteins. The two main intestinal lipoproteins are chylomicron (CM) and very low-density lipoprotein (VLDL). Unfortunately, studies on the CM biogenesis and intestinal transport of dietary fats have been hampered by the lack of an adequate in vitro model. In this study, we investigated the possible factors that might increase the efficiency of CM production by Caco-2 cells. We utilized sequential NaCl gradient ultracentrifugation to isolate the CMs that were secreted by the Caco-2 cells. To confirm the successful isolation of the CMs, we performed Fat Red 7B staining, …

Roles Of Dopamine Receptor On Chemosensory And Mechanosensory Primary Cilia In Renal Epithelial Cells, Viralkumar S. Upadhyay, Brian S. Muntean, Samred H. Kathem, Jangyoun J. Hwang, Wissam A. Aboualaiwi, Surya M. Nauli

Pharmacy Faculty Articles and Research

Dopamine plays a number of important physiological roles. However, activation of dopamine receptor type-5 (DR5) and its effect in renal epithelial cells have not been studied. Here, we show for the first time that DR5 is localized to primary cilia of LLCPK kidney cells. Renal epithelial cilia are mechanosensory organelles that sense and respond to tubular fluid-flow in the kidney. To determine the roles of DR5 and sensory cilia, we used dopamine to non-selectively and fenoldopam to selectively activate ciliary DR5. Compared to mock treatment, dopamine treated cells significantly increases the length of cilia. Fenoldopam further increases the length of …

Sensing A Sensor: Identifying The Mechanosensory Function Of Primary Cilia, Rahul M. Prasad, Xingjian Jin, Surya M. Nauli

Pharmacy Faculty Articles and Research

Over the past decade, primary cilia have emerged as the premier means by which cells sense and transduce mechanical stimuli. Primary cilia are sensory organelles that have been shown to be vitally involved in the mechanosensation of urine in the renal nephron, bile in the hepatic biliary system, digestive fluid in the pancreatic duct, dentin in dental pulp, lacunocanalicular fluid in bone and cartilage, and blood in vasculature. The prevalence of primary cilia among mammalian cell types is matched by the tremendously varied disease states caused by both structural and functional defects in cilia. In the process of delineating the …

The Roles Of Primary Cilia In Polycystic Kidney Disease, Samred H. Kathem, Ashraf M. Mohieldin, Surya M. Nauli

Pharmacy Faculty Articles and Research

Autosomal dominant polycystic kidney disease (ADPKD) is an inherited genetic disorder that results in progressive renal cyst formation with ultimate loss of renal function and other systemic disorders. These systemic disorders include abnormalities in cardiovascular, portal, pancreatic and gastrointestinal systems. ADPKD is considered to be among the ciliopathy diseases due to the association with abnormal primary cilia function. In order to understand the full course of primary cilia and its association with ADPKD, the structure, functions and role of primary cilia have been meticulously investigated. As a result, the focus on primary cilia has emerged to support the vital roles …

Non-Motile Primary Cilia As Fluid Shear Stress Mechanosensors, Surya M. Nauli, Xingjian Jin, Wissam A. Aboualaiwi, Wassim El-Jouni, Xuefeng Su, Jing Zhou

Pharmacy Faculty Articles and Research

Primary cilia are sensory organelles that transmit extracellular signals into intracellular biochemical responses. Structural and functional defects in primary cilia are associated with a group of human diseases, known as ciliopathies, with phenotypes ranging from cystic kidney and obesity to blindness and mental retardation. Primary cilia mediate mechano- and chemosensation in many cell types. The mechanosensory function of the primary cilia requires the atypical G-protein-coupled receptor polycystin-1 and the calcium-permeable nonselective cation channel polycystin-2. Mechanical stimulations such as fluid-shear stress of the primary cilia initiate intracellular calcium rise, nitric oxide release, and protein modifications. In this review, we describe a …

Primary Cilia Regulates The Directional Migration And Barrier Integrity Of Endothelial Cells Through The Modulation Of Hsp27 Dependent Actin Cytoskeletal Organization, Thomas J. Jones, Ravi K. Adapala, Werner J. Geldenhuys, Chris Bursley, Wissam A. Aboualaiwi, Surya M. Nauli, Charles K. Thodeti

Pharmacy Faculty Articles and Research

Cilia are mechanosensing organelles that communicate extracellular signals into intracellular responses. Altered functions of primary cilia play a key role in the development of various diseases including polycystic kidney disease. Here, we show that endothelial cells from the oak ridge polycystic kidney (Tg737orpk/orpk) mouse, with impaired cilia assembly, exhibit a reduction in the actin stress fibers and focal adhesions compared to wild type. In contrast, endothelial cells from polycystin-1 deficient mice (pkd1null/null), with impaired cilia function, display robust stress fibers and focal adhesion assembly. We found that the Tg737orpk/orpk cells exhibit impaired directional migration and endothelial cell monolayer permeability compared …

Cilostazol Prevents Endothelin-Induced Smooth Muscle Constriction And Proliferation, Yoshifumi Kawanabe, Maki Takahashi, Xingjian Jin, Shakila Abdul-Majeed, Andromeda M. Nauli, Youssef Sari, Surya M. Nauli

Pharmacy Faculty Articles and Research

Cilostazol is a phosphodiesterase inhibitor that has been shown to inhibit platelet activation. Endothelin is known to be the most potent endogenous growth promoting and vasoactive peptide. In patients and animal models with stroke, the level of circulating endothelin increases and complicates the recovery progress contributed by vascular constriction (an immediate pathology) and vascular proliferation (a long-term pathology). However, the effects of cilostazol on endothelin have not been explored. To demonstrate the dual-antagonizing effects of cilostazol on vasoconstriction and cell proliferation induced by endothelin, we used primary culture of mouse vascular smooth muscle cells in vitro, mouse femoral artery ex …

Calcium-Mediated Mechanisms Of Cystic Expansion, Shakila Abdul-Majeed, Surya M. Nauli

Pharmacy Faculty Articles and Research

In this review, we will discuss several well-accepted signaling pathways toward calcium-mediated mechanisms of cystic expansion. The second messenger calcium ion has contributed to a vast diversity of signal transduction pathways. We will dissect calcium signaling as a possible mechanism that contributes to renal cyst formation. Because cytosolic calcium also regulates an array of signaling pathways, we will first discuss cilia-induced calcium fluxes, followed by Wnt signaling that has attributed to much-discussed planar cell polarity. We will then look at the relationship between cytosolic calcium and cAMP as one of the most important aspects of cyst progression. The signaling of …

Multiple Protein Kinases Determine The Phosphorylated State Of The Small Heat Shock Protein, Hsp27, In Sh-Sy5y Neuroblastoma Cells, Linda A. Dokas, Amy M. Malone, Frederick E. Williams, Surya M. Nauli, William S. Messer Jr.

Pharmacy Faculty Articles and Research

In SH-SY5Y human neuroblastoma cells, the cholinergic agonist, carbachol, stimulates phosphorylation of the small heat shock protein 27 (HSP27). Carbachol increases phosphorylation of both Ser-82 and Ser-78 while the phorbol ester, phorbol-12, 13-dibutyrate (PDB) affects only Ser-82. Muscarinic receptor activation by carbachol was confirmed by sensitivity of Ser-82 phosphorylation to hyoscyamine with no effect of nicotine or bradykinin. This response to carbachol is partially reduced by inhibition of protein kinase C (PKC) with GF 109203X and p38 mitogen-activated protein kinase (MAPK) with SB 203580. In contrast, phosphorylation produced by PDB is completely reversed by GF 109203X or CID 755673, an …

Multimodal Spectral Imaging Of Cells Using A Transmission Diffraction Grating On A Light Microscope, Dragan Isailovic, Yang Xu, Tyler Copus, Suraj Saraswat, Surya M. Nauli

Pharmacy Faculty Articles and Research

A multimodal methodology for spectral imaging of cells is presented. The spectral imaging setup uses a transmission diffraction grating on a light microscope to concurrently record spectral images of cells and cellular organelles by fluorescence, darkfield, brightfield, and differential interference contrast (DIC) spectral microscopy. Initially, the setup was applied for fluorescence spectral imaging of yeast and mammalian cells labeled with multiple fluorophores. Fluorescence signals originating from fluorescently labeled biomolecules in cells were collected through triple or single filter cubes, separated by the grating, and imaged using a charge-coupled device (CCD) camera. Cellular components such as nuclei, cytoskeleton, and mitochondria were …

Polycystic Diseases In Visceral Organs, Shakila Abdul-Majeed, Surya M. Nauli

Pharmacy Faculty Articles and Research

Primary cilia are nonmotile, microtubule-based, antenna-like organelles projecting from the apical surface of most mammalian cells. Elegant studies have established the importance of ciliary structure and function in signal transduction and the sensory roles of cilia in maintaining healthy cellular state. In particular, dysfunctional cilia have been implicated in a large number of diseases mainly characterized by the presence of fluid-filled cysts in various organs. Aside from polycystic kidney disease (PKD), however, the roles of cilia in polycystic liver disease (PLD), polycystic pancreas disease (PPD), and polycystic ovarian syndrome (PCOS) are still very vague. In addition, although gender and sex …

Endothelin, Yoshifumi Kawanabe, Surya M. Nauli

Pharmacy Faculty Articles and Research

Endothelin-1 is the most potent vasoconstrictor agent currently identified, and it was originally isolated and characterized from the culture media of aortic endothelial cells. Two other isoforms, termed endothelin-2 and endothelin-3, were subsequently identified, along with structural homologues isolated from the venom of Actractapis eng-addensis known as the sarafotoxins. In this review, we will discuss the basic science of endothelins, endothelin-converting enzymes, and endothelin receptors. Only concise background information pertinent to clinical physician is provided. Next we will describe the pathophysiological roles of endothelin-1 in pulmonary arterial hypertension, heart failure, systemic hypertension, and female malignancies, with emphasis on ovarian cancer. …

An Upper Limit For Macromolecular Crowding Effects, Andrew C. Miklos, Congang Li, Courtney D. Sorell, L. Andrew Lyon, Gary J. Pielak

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background: Solutions containing high macromolecule concentrations are predicted to affect a number of protein properties compared to those properties in dilute solution. In cells, these macromolecular crowders have a large range of sizes and can occupy 30% or more of the available volume. We chose to study the stability and ps-ns internal dynamics of a globular protein whose radius is similar to 2 nm when crowded by a synthetic microgel composed of poly(N-isopropylacrylamide-co-acrylic acid) with particle radii of similar to 300 nm.

Results: Our studies revealed no change in protein rotational or ps-ns backbone dynamics and only mild …

Failure To Ubiquitinate C-Met Leads To Hyperactivation Of Mtor Signaling In A Mouse Model Of Autosomal Dominant Polycystic Kidney Disease, Shan Qin, Mary Taglienti, Surya M. Nauli, Leah Contrino, Ayumi Takakura, Jing Zhou, Jordan A. Kreidberg

Pharmacy Faculty Articles and Research

Autosomal dominant polycystic kidney disease (ADPKD) is a common inherited disorder that is caused by mutations at two loci, polycystin 1 (PKD1) and polycystin 2 (PKD2). It is characterized by the formation of multiple cysts in the kidneys that can lead to chronic renal failure. Previous studies have suggested a role for hyperactivation of mammalian target of rapamycin (mTOR) in cystogenesis, but the etiology of mTOR hyperactivation has not been fully elucidated. In this report we have shown that mTOR is hyperactivated. in Pkd1-null mouse cells due to failure of the HGF receptor c-Met to be properly ubiquitinated and subsequently …

Hypertension In Autosomal Dominant Polycystic Kidney Disease: A Clinical And Basic Science Perspective, Shobha Ratnam, Surya M. Nauli

Pharmacy Faculty Articles and Research

Cardiovascular complications are major causes of morbidity and mortality in patients with autosomal dominant polycystic kidney disease (ADPKD). In particular, hypertension is insidious and remains a continuous problem that evolves during the course of the disease. Hypertension in ADPKD has been associated with abnormality in the renin-angiotensin-aldosterone system (RAAS). Early vascular changes have also been reported in young ADPKD patients. In addition, the cellular functions of mechanosensory cilia within vascular system have emerged recently. The basic and clinical perspectives of RAAS, vascular remodeling and sensory cilia are reviewed with regard to hypertension in ADPKD

Chemosensitization Of Cancer Cells By Sirna Using Targeted Nanogel Delivery, Erin B. Dickerson, William H. Blackburn, Michael H. Smith, Laura B. Kapa, L. Andrew Lyon, John F. Mcdonald

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background: Chemoresistance is a major obstacle in cancer treatment. Targeted therapies that enhance cancer cell sensitivity to chemotherapeutic agents have the potential to increase drug efficacy while reducing toxic effects on untargeted cells. Targeted cancer therapy by RNA interference (RNAi) is a relatively new approach that can be used to reversibly silence genes in vivo by selectively targeting genes such as the epidermal growth factor receptor (EGFR), which has been shown to increase the sensitivity of cancer cells to taxane chemotherapy. However, delivery represents the main hurdle for the broad development of RNAi therapeutics.

Methods: We report here …

Primary Cilia: Highly Sophisticated Biological Sensors, Wissam A. Aboualaiwi, Shao T. Lo, Surya M. Nauli

Pharmacy Faculty Articles and Research

Primary cilia, thin hair-like structures protruding from the apical surface of most mammalian cells, have gained the attention of many researchers over the past decade. Primary cilia are microtubule-filled sensory organelles that are enclosed within the ciliary membrane. They originate at the cell surface from the mother centriole that becomes the mature basal body. In this review, we will discuss recent literatures on the roles of cilia as sophisticated sensory organelles. With particular emphasis on vascular endothelia and renal epithelia, the mechanosensory role of cilia in sensing fluid shear stress will be discussed. Also highlighted is the ciliary involvement in …

Ciliary Dysfunction In Polycystic Kidney Disease: An Emerging Model With Polarizing Potential, Robert J. Kolb, Surya M. Nauli

Pharmacy Faculty Articles and Research

The majority of different cell types in the human body have a cilium, a thin rod-like structure of uniquely arranged microtubules that are encapsulated by the surface plasma membrane. The cilium originates from a basal body, a mature centriole that has migrated and docked to the cell surface. The non-motile cilia are microtubule-based organelles that are generally considered sensory structures. The purpose of this review is to discuss the practicality of the ciliary hypothesis as a unifying concept for polycystic kidney disease and to review current literature in the field of cilium biology, as it relates to mechanosensation and planar …

Fibrocystin/Polyductin, Found In The Same Protein Complex With Polycystin-2, Regulates Calcium Responses In Kidney Epithelia, Shizuan Wang, Jingjing Zhang, Surya M. Nauli, Xiaogang Li, Patrick G. Starremans, Ying Luo, Kristina A. Roberts, Jing Zhou

Pharmacy Faculty Articles and Research

Recent evidence suggests that fibrocystin/polyductin (FPC), polycystin-1 (PC1), and polycystin-2 (PC2) are all localized at the plasma membrane and the primary cilium, where PC1 and PC2 contribute to fluid How sensation and may function in the same mechanotransduction pathways. To further define the exact subcellular localization of FPC, the protein product encoded by the PKHD1 gene responsible for autosomal recessive polycystic kidney disease (PKD) in humans, and whether FPC has direct and/or indirect cross talk with PC2, which, in turn, is pivotal for the pathogenesis of autosomal dominant PKD, we performed double immunostaining and coimmunoprecipitation as well as a microfluorimetry …