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Ruan J, Liang D, Yan W, Zhong Y, Talley DC, Rai G, Tao D, LeClair CA, Simeonov A, Zhang Y, Chen F, Quinney NL, Boyles SE, Cholon DM, Gentzsch M, Henderson MJ, Xue F, Fang S. A small-molecule inhibitor and degrader of the RNF5 ubiquitin ligase. Mol Biol Cell 2022; 33:ar120. [PMID: 36074076 PMCID: PMC9634977 DOI: 10.1091/mbc.e22-06-0233] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
RNF5 E3 ubiquitin ligase has multiple biological roles and has been linked to the development of severe diseases such as cystic fibrosis, acute myeloid leukemia, and certain viral infections, emphasizing the importance of discovering small-molecule RNF5 modulators for research and drug development. The present study describes the synthesis of a new benzo[b]thiophene derivative, FX12, that acts as a selective small-molecule inhibitor and degrader of RNF5. We initially identified the previously reported STAT3 inhibitor, Stattic, as an inhibitor of dislocation of misfolded proteins from the endoplasmic reticulum (ER) lumen to the cytosol in ER-associated degradation. A concise structure-activity relationship campaign (SAR) around the Stattic chemotype led to the synthesis of FX12, which has diminished activity in inhibition of STAT3 activation and retains dislocation inhibitory activity. FX12 binds to RNF5 and inhibits its E3 activity in vitro as well as promoting proteasomal degradation of RNF5 in cells. RNF5 as a molecular target for FX12 was supported by the facts that FX12 requires RNF5 to inhibit dislocation and negatively regulates RNF5 function. Thus, this study developed a small-molecule inhibitor and degrader of the RNF5 ubiquitin ligase, providing a chemical biology tool for RNF5 research and therapeutic development.
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Affiliation(s)
- Jingjing Ruan
- Center for Biomedical Engineering and Technology, Department of Physiology, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201,First Affiliated Hospital and
| | - Dongdong Liang
- University of Maryland School of Pharmacy, Baltimore, MD 21201
| | - Wenjing Yan
- Center for Biomedical Engineering and Technology, Department of Physiology, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Yongwang Zhong
- Center for Biomedical Engineering and Technology, Department of Physiology, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Daniel C. Talley
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Ganesha Rai
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Dingyin Tao
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Christopher A. LeClair
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Anton Simeonov
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Yinghua Zhang
- Center for Innovative Biomedical Resources, Biosensor Core, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Feihu Chen
- School of Pharmacy, Anhui Medical University, Hefei, Anhui 230032, China
| | | | | | | | - Martina Gentzsch
- Marsico Lung Institute and Cystic Fibrosis Research Center,Department of Pediatric Pulmonology, and,Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Mark J. Henderson
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850,*Address corespondence to: Shengyun Fang (lead contact) (); Mark J. Henderson (); Fengtian Xue ()
| | - Fengtian Xue
- University of Maryland School of Pharmacy, Baltimore, MD 21201,*Address corespondence to: Shengyun Fang (lead contact) (); Mark J. Henderson (); Fengtian Xue ()
| | - Shengyun Fang
- Center for Biomedical Engineering and Technology, Department of Physiology, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201,*Address corespondence to: Shengyun Fang (lead contact) (); Mark J. Henderson (); Fengtian Xue ()
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Valosin-Containing Protein (VCP)/p97: A Prognostic Biomarker and Therapeutic Target in Cancer. Int J Mol Sci 2021; 22:ijms221810177. [PMID: 34576340 PMCID: PMC8469696 DOI: 10.3390/ijms221810177] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/17/2021] [Accepted: 09/18/2021] [Indexed: 01/02/2023] Open
Abstract
Valosin-containing protein (VCP)/p97, a member of the AAA+ ATPase family, is a molecular chaperone recruited to the endoplasmic reticulum (ER) membrane by binding to membrane adapters (nuclear protein localization protein 4 (NPL4), p47 and ubiquitin regulatory X (UBX) domain-containing protein 1 (UBXD1)), where it is involved in ER-associated protein degradation (ERAD). However, VCP/p97 interacts with many cofactors to participate in different cellular processes that are critical for cancer cell survival and aggressiveness. Indeed, VCP/p97 is reported to be overexpressed in many cancer types and is considered a potential cancer biomarker and therapeutic target. This review summarizes the role of VCP/p97 in different cancers and the advances in the discovery of small-molecule inhibitors with therapeutic potential, focusing on the challenges associated with cancer-related VCP mutations in the mechanisms of resistance to inhibitors.
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Abstract
The development of molecular nanostructures with well-defined particle size and shape is of eminent interest in biomedicine. Among many studied nanostructures, dendrimers represent the group of those most thoroughly characterized ones. Due to their unique structure and properties, dendrimers are very attractive for medical and pharmaceutical applications. Owing to the controllable cavities inside the dendrimer, guest molecules may be encapsulated, and highly reactive terminal groups are susceptible to further modifications, e.g., to facilitate target delivery. To understand the potential of these nanoparticles and to predict and avoid any adverse cellular reactions, it is necessary to know the mechanisms responsible for an efficient dendrimer uptake and the destination of their intracellular journey. In this article, we summarize the results of studies describing the dendrimer uptake, traffic, and efflux mechanisms depending on features of specific nanoparticles and cell types. We also present mechanisms of dendrimers responsible for toxicity and alteration in signal transduction pathways at the cellular level.
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Affiliation(s)
- Barbara Ziemba
- Department of Clinical and Laboratory Genetics, Medical University of Lodz, Lodz, Poland
| | - Maciej Borowiec
- Department of Clinical and Laboratory Genetics, Medical University of Lodz, Lodz, Poland
| | - Ida Franiak-Pietryga
- Department of Clinical and Laboratory Genetics, Medical University of Lodz, Lodz, Poland.,Moores Cancer Center, University of California San Diego, La Jolla, CA, USA
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Bouwer MF, Hamilton KE, Jonker PB, Kuiper SR, Louters LL, Looyenga BD. NMS-873 functions as a dual inhibitor of mitochondrial oxidative phosphorylation. Biochimie 2021; 185:33-42. [PMID: 33727138 DOI: 10.1016/j.biochi.2021.03.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/02/2021] [Accepted: 03/06/2021] [Indexed: 11/18/2022]
Abstract
Small-molecule inhibitors of enzyme function are critical tools for the study of cell biological processes and for treatment of human disease. Identifying inhibitors with suitable specificity and selectivity for single enzymes, however, remains a challenge. In this study we describe our serendipitous discovery that NMS-873, a compound that was previously identified as a highly selective allosteric inhibitor of the ATPase valosin-containing protein (VCP/p97), rapidly induces aerobic fermentation in cultured human and mouse cells. Our further investigation uncovered an unexpected off-target effect of NMS-873 on mitochondrial oxidative phosphorylation, specifically as a dual inhibitor of Complex I and ATP synthase. This work points to the need for caution regarding the interpretation of cell survival data associated with NMS-873 treatment and indicates that cellular toxicity associated with its use may be caused by both VCP/p97-dependent and VCP/p97-independent mechanisms.
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Affiliation(s)
- Miranda F Bouwer
- Calvin University, Department of Chemistry & Biochemistry, 1726 Knollcrest Circle SE, Grand Rapids, MI, 49546, USA
| | - Kathryn E Hamilton
- Calvin University, Department of Chemistry & Biochemistry, 1726 Knollcrest Circle SE, Grand Rapids, MI, 49546, USA
| | - Patrick B Jonker
- Calvin University, Department of Chemistry & Biochemistry, 1726 Knollcrest Circle SE, Grand Rapids, MI, 49546, USA
| | - Sam R Kuiper
- Calvin University, Department of Chemistry & Biochemistry, 1726 Knollcrest Circle SE, Grand Rapids, MI, 49546, USA
| | - Larry L Louters
- Calvin University, Department of Chemistry & Biochemistry, 1726 Knollcrest Circle SE, Grand Rapids, MI, 49546, USA
| | - Brendan D Looyenga
- Calvin University, Department of Chemistry & Biochemistry, 1726 Knollcrest Circle SE, Grand Rapids, MI, 49546, USA.
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Vij N. Synthesis and Evaluation of Dendrimers for Autophagy Augmentation and Alleviation of Obstructive Lung Diseases. Methods Mol Biol 2021; 2118:155-164. [PMID: 32152978 DOI: 10.1007/978-1-0716-0319-2_12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Preservation of cellular homeostasis requires constant synthesis of fresh proteins and cellular organelles and efficient degradation or removal of damaged proteins and cellular components. This involves two cellular degradation processes or molecular mechanisms: the ubiquitin-proteasome and autophagy-lysosomal systems. Impairment of these catabolic processes has been linked to pathogenesis of a variety of chronic obstructive lung diseases such as COPD (chronic obstructive pulmonary disease) and CF (cystic fibrosis). Proteosomal and autophagic functions (proteostasis) are known to decline with advancing age leading to accumulation of cellular debris and proteins, initiating cellular senescence or death and accelerating lung aging. Obstructive lung diseases associated with airway hyperinflammation and mucus obstruction provide major challenges to the delivery and therapeutic efficacy of nanotherapeutics systems as they need to bypass the airway defense. Targeted autophagy augmentation has emerged, as a promising therapeutic utility for alleviating obstructive lung diseases, and promoting healthy aging. A targeted dendrimer-based approach has been designed to penetrate the airway obstruction and allow the selective correction of proteostasis/autophagy in the diseased cells while circumventing the side effects. This report describes methods for synthesis and therapeutic evaluation of autophagy augmenting dendrimers in the treatment of obstructive lung disease(s). The formulations and methods of autophagy augmentation described here are currently under clinical development in our laboratory for alleviating pathogenesis and progression of chronic obstructive lung diseases, and promoting healthy aging.
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Affiliation(s)
- Neeraj Vij
- Department of Pediatrics and Pulmonary Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA. .,4Dx Limited, Los Angeles, CA, USA. .,VIJ BIOTECH & PRECISION THERANOSTICS INC, Baltimore, MD, USA.
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Cayli S, Sahin C, Sanci TO, Nakkas H. Inhibition of p97/VCP function leads to defective autophagosome maturation, cell cycle arrest and apoptosis in mouse Sertoli cells. Theriogenology 2020; 158:196-206. [PMID: 32966945 DOI: 10.1016/j.theriogenology.2020.09.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 09/07/2020] [Accepted: 09/14/2020] [Indexed: 12/16/2022]
Abstract
p97/valosin-containing protein (VCP) is expressed in many cells and plays critical functions in a broad range of diverse cellular processes. Because it is expressed in the mouse testes, predominantly in Sertoli cells, and is known to play a critical role in autophagy and apoptosis in different cell types, we set out to investigate its function in autophagosome maturation, apoptosis and cell cycle arrest in a mouse Sertoli cell line. To study the mechanism of p97/VCP action, p97/VCP siRNA and a specific p97/VCP inhibitor, N2,N4-dibenzylquinazoline-2,4-diamine (DBeQ), were used in the mouse 15P1 Sertoli cell line. Loss of p97/VCP activity due to DBeQ exposure and silencing of p97/VCP (siVCP) expression results in autophagosome (LC3 and p62) accumulation in the cytoplasm of Sertoli cells. The coexpression of autophagosomal and lysosomal markers (LAMP1 and LAMP2) was reduced in cells in which p97/VCP expression had been inactivated. To better understand in which step of autophagy p97/VCP functions, the interaction between autophagosomal and autolysosomal markers was studied by coimmunoprecipitation and colocalization experiments. The interaction between autophagosomal markers and lysosomal markers decreased in siVCP-expressing and DBeQ-exposed cells. Moreover, the expression of siVCP and DBeQ exposure caused cytoplasmic vacuolation, induced caspase 3-7-mediated cell death and decreased cell cycle progression in mouse Sertoli cells. Taken together, the results show that p97/VCP is essential for autophagosome maturation and cell survival in mouse Sertoli cells. When these functions are prevented, impaired autophagy and apoptosis may have a detrimental effect on germ cells and cause male infertility.
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Affiliation(s)
- Sevil Cayli
- Ankara Yıldırım Beyazıt University, Medical Faculty, Dept. of Histology and Embryology, Ankara, Turkey.
| | - Cansu Sahin
- Ankara Yıldırım Beyazıt University, Medical Faculty, Dept. of Histology and Embryology, Ankara, Turkey
| | - Tuba Ozdemir Sanci
- Ankara Yıldırım Beyazıt University, Medical Faculty, Dept. of Histology and Embryology, Ankara, Turkey
| | - Hilal Nakkas
- Ankara Yıldırım Beyazıt University, Medical Faculty, Dept. of Histology and Embryology, Ankara, Turkey
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Sui X, Pan M, Li YM. Insights into the Design of p97-targeting Small Molecules from Structural Studies on p97 Functional Mechanism. Curr Med Chem 2020; 27:298-316. [PMID: 31584361 DOI: 10.2174/0929867326666191004162411] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 08/24/2019] [Accepted: 08/27/2019] [Indexed: 12/14/2022]
Abstract
p97, also known as valosin-containing protein or CDC48, is a member of the AAA+ protein family that is highly conserved in eukaryotes. It binds to various cofactors in the body to perform its protein-unfolding function and participates in DNA repair, degradation of subcellular membrane proteins, and protein quality control pathways, among other processes. Its malfunction can lead to many diseases, such as inclusion body myopathy, associated with Paget's disease of bone and/or frontotemporal dementia, amyotrophic lateral sclerosis disease, and others. In recent years, many small-molecule inhibitors have been deployed against p97, including bis (diethyldithiocarbamate)- copper and CB-5083, which entered the first phase of clinical tests but failed. One bottleneck in the design of p97 drugs is that its molecular mechanism remains unclear. This paper summarizes recent studies on the molecular mechanisms of p97, which may lead to insight into how the next generation of small molecules targeting p97 can be designed.
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Affiliation(s)
- Xin Sui
- Department of Chemistry, Tsinghua University, Beijing 100086, China
| | - Man Pan
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois 60637, United States
| | - Yi-Ming Li
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui 230009, China
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Brockman SM, Bodas M, Silverberg D, Sharma A, Vij N. Dendrimer-based selective autophagy-induction rescues ΔF508-CFTR and inhibits Pseudomonas aeruginosa infection in cystic fibrosis. PLoS One 2017; 12:e0184793. [PMID: 28902888 PMCID: PMC5597233 DOI: 10.1371/journal.pone.0184793] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 08/31/2017] [Indexed: 12/11/2022] Open
Abstract
Background Cystic Fibrosis (CF) is a genetic disorder caused by mutation(s) in the CF-transmembrane conductance regulator (Cftr) gene. The most common mutation, ΔF508, leads to accumulation of defective-CFTR protein in aggresome-bodies. Additionally, Pseudomonas aeruginosa (Pa), a common CF pathogen, exacerbates obstructive CF lung pathology. In the present study, we aimed to develop and test a novel strategy to improve the bioavailability and potentially achieve targeted drug delivery of cysteamine, a potent autophagy-inducing drug with anti-bacterial properties, by developing a dendrimer (PAMAM-DEN)-based cysteamine analogue. Results We first evaluated the effect of dendrimer-based cysteamine analogue (PAMAM-DENCYS) on the intrinsic autophagy response in IB3-1 cells and observed a significant reduction in Ub-RFP and LC3-GFP co-localization (aggresome-bodies) by PAMAM-DENCYS treatment as compared to plain dendrimer (PAMAM-DEN) control. Next, we observed that PAMAM-DENCYS treatment shows a modest rescue of ΔF508-CFTR as the C-form. Moreover, immunofluorescence microscopy of HEK-293 cells transfected with ΔF508-CFTR-GFP showed that PAMAM-DENCYS is able to rescue the misfolded-ΔF508-CFTR from aggresome-bodies by inducing its trafficking to the plasma membrane. We further verified these results by flow cytometry and observed significant (p<0.05; PAMAM-DEN vs. PAMAM-DENCYS) rescue of membrane-ΔF508-CFTR with PAMAM-DENCYS treatment using non-permeabilized IB3-1 cells immunostained for CFTR. Finally, we assessed the autophagy-mediated bacterial clearance potential of PAMAM-DENCYS by treating IB3-1 cells infected with PA01-GFP, and observed a significant (p<0.01; PAMAM-DEN vs. PAMAM-DENCYS) decrease in intracellular bacterial counts by immunofluorescence microscopy and flow cytometry. Also, PAMAM-DENCYS treatment significantly inhibits the growth of PA01-GFP bacteria and demonstrates potent mucolytic properties. Conclusions We demonstrate here the efficacy of dendrimer-based autophagy-induction in preventing sequestration of ΔF508-CFTR to aggresome-bodies while promoting its trafficking to the plasma membrane. Moreover, PAMAM-DENCYS decreases Pa infection and growth, while showing mucolytic properties, suggesting its potential in rescuing Pa-induced ΔF508-CF lung disease that warrants further investigation in CF murine model.
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Affiliation(s)
- Scott Mackenzie Brockman
- College of Medicine, Central Michigan University, Mount Pleasant, Michigan, United States of America
| | - Manish Bodas
- College of Medicine, Central Michigan University, Mount Pleasant, Michigan, United States of America
| | - David Silverberg
- College of Medicine, Central Michigan University, Mount Pleasant, Michigan, United States of America
| | - Ajit Sharma
- Department of Chemistry and Biochemistry, Central Michigan University, Mount Pleasant, Michigan, United States of America
| | - Neeraj Vij
- College of Medicine, Central Michigan University, Mount Pleasant, Michigan, United States of America
- Department of Pediatric Respiratory Sciences, The Johns Hopkins School of Medicine, Baltimore, Maryland, United States of America
- * E-mail:
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The AAA+ ATPase p97, a cellular multitool. Biochem J 2017; 474:2953-2976. [PMID: 28819009 PMCID: PMC5559722 DOI: 10.1042/bcj20160783] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 07/17/2017] [Accepted: 07/21/2017] [Indexed: 12/17/2022]
Abstract
The AAA+ (ATPases associated with diverse cellular activities) ATPase p97 is essential to a wide range of cellular functions, including endoplasmic reticulum-associated degradation, membrane fusion, NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) activation and chromatin-associated processes, which are regulated by ubiquitination. p97 acts downstream from ubiquitin signaling events and utilizes the energy from ATP hydrolysis to extract its substrate proteins from cellular structures or multiprotein complexes. A multitude of p97 cofactors have evolved which are essential to p97 function. Ubiquitin-interacting domains and p97-binding domains combine to form bi-functional cofactors, whose complexes with p97 enable the enzyme to interact with a wide range of ubiquitinated substrates. A set of mutations in p97 have been shown to cause the multisystem proteinopathy inclusion body myopathy associated with Paget's disease of bone and frontotemporal dementia. In addition, p97 inhibition has been identified as a promising approach to provoke proteotoxic stress in tumors. In this review, we will describe the cellular processes governed by p97, how the cofactors interact with both p97 and its ubiquitinated substrates, p97 enzymology and the current status in developing p97 inhibitors for cancer therapy.
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Vij N. Nano-based rescue of dysfunctional autophagy in chronic obstructive lung diseases. Expert Opin Drug Deliv 2016; 14:483-489. [PMID: 27561233 DOI: 10.1080/17425247.2016.1223040] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
INTRODUCTION ΔF508-CFTR (cystic fibrosis transmembrane conductance regulator) is a common CF-mutation that is known to induce oxidative-inflammatory stress through activation of reactive oxygen species (ROS), which induces autophagy-impairment resulting in accumulation of CFTR in aggresome-bodies. Cysteamine, the reduced form of cystamine, is a FDA-approved drug that has anti-oxidant, anti-bacterial, and mucolytic properties. This drug has been shown in a recent clinical trial to decrease lung inflammation and improve lung function in CF patients by potentially restoring autophagy and allowing CFTR to be trafficked to the cell membrane. Areas covered: The delivery of cysteamine to airway epithelia of chronic subjects prerequisite the need for a delivery system to allow rescue of dysfunctional autophagy. Expert opinion: We anticipate based on our ongoing studies that PLGA-PEG- or Dendrimer-mediated cysteamine delivery could allow sustained airway delivery over standard cysteamine tablets or delay release capsules that are currently used for systemic treatment. In addition, proposed nano-based autophagy induction strategy can also allow rescue of cigarette smoke (CS) induced acquired-CFTR dysfunction seen in chronic obstructive pulmonary disease (COPD)-emphysema subjects. The CS induced acquired-CFTR dysfunction involves CFTR-accumulation in aggresome-bodies that can be rescued by an autophagy-inducing antioxidant drug, cysteamine. Moreover, chronic CS-exposure generates ROS that induces overall protein-misfolding and aggregation of ubiquitinated-proteins as aggresome-bodies via autophagy-impairment that can be also be resolved by treatment with autophagy-inducing antioxidant drug, cysteamine.
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Affiliation(s)
- Neeraj Vij
- a College of Medicine , Central Michigan University , Mount Pleasant , MI , USA.,b Department of Pediatric Respiratory Sciences , The Johns Hopkins School of Medicine , Baltimore , MD , USA
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