1
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Akhigbe RE, Oladipo AA, Oyedokun PA, Hamed MA, Okeleji LO, Ajayi AF. Upregulation of Uric Acid Production and Caspase 3 Signalling Mediates Rohypnol-Induced Cardiorenal Damage. Cardiovasc Toxicol 2022; 22:419-435. [PMID: 35103933 DOI: 10.1007/s12012-022-09723-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 01/19/2022] [Indexed: 12/22/2022]
Abstract
The global prevalence of illicit drug use is on the increase with attendant complications like cardiorenal collapse. One such substance of abuse is rohypnol. Despite its ban in most countries, it remains a popular substance of abuse. Whether or not rohypnol induces cardiorenal injury and the associated mechanism is yet to be elucidated. Therefore, the present study investigated the effect of rohypnol on cardiorenal integrity and functions, and glucolipid metabolism. Forty-eight male Wistar rats randomized into six groups (n = 8/group) received (per os) vehicle, low-dose (2 mg/kg) and high-dose (4 mg/kg) rohypnol once daily for twenty eight days, with or without a cessation period. Data revealed that rohypnol exposure irreversibly caused insulin resistance, hyperglycaemia, and dyslipidaemia. This was accompanied by reduced cardiorenal mass and impaired cardiorenal cytoarchitecture and function. Furthermore, rohypnol treatment promoted oxidative stress, inflammation, genotoxicity, and decreased cardiorenal activities of Na+-K+-ATPase, Ca2+-ATPase, and Mg2+-ATPase. These alterations were associated with enhanced uric acid generation and caspase 3 activity in the cardiorenal complex. Thus, this study reveals that rohypnol exposure triggers cardiorenal toxicity with incident insulin resistance, glucolipid and cardiorenal proton pump dysregulation, altered redox state, and inflammation via enhancement of uric acid generation and caspase 3-dependent mechanism.
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Affiliation(s)
- R E Akhigbe
- Reproductive Physiology and Bioinformatics Research Unit, Department of Physiology, Ladoke Akintola University of Technology, Ogbomoso, Oyo State, Nigeria.,Reproductive Biology and Toxicology Research Laboratories, Oasis of Grace Hospital, Osogbo, Osun State, Nigeria.,Department of Chemical Sciences, Kings University, Odeomu, Osun, Nigeria
| | - A A Oladipo
- Reproductive Physiology and Bioinformatics Research Unit, Department of Physiology, Ladoke Akintola University of Technology, Ogbomoso, Oyo State, Nigeria
| | - P A Oyedokun
- Reproductive Physiology and Bioinformatics Research Unit, Department of Physiology, Ladoke Akintola University of Technology, Ogbomoso, Oyo State, Nigeria
| | - M A Hamed
- Reproductive Biology and Toxicology Research Laboratories, Oasis of Grace Hospital, Osogbo, Osun State, Nigeria.,Buntai Medical and Diagnostic Laboratories, Osogbo, Nigeria
| | - L O Okeleji
- Cardio-Thoracic Unit, Obafemi Awolowo University Teaching Hospital, Ile-Ife, Osun State, Nigeria
| | - A F Ajayi
- Reproductive Physiology and Bioinformatics Research Unit, Department of Physiology, Ladoke Akintola University of Technology, Ogbomoso, Oyo State, Nigeria. .,Department of Human Physiology, Faculty of Basic Medical Sciences, Baze University, Abuja, Nigeria.
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2
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Wang Q, Cao Z, Du B, Zhang Q, Chen L, Wang X, Yuan Z, Wang P, He R, Shan J, Zhao Y, Miao L. Membrane contact site-dependent cholesterol transport regulates Na +/K +-ATPase polarization and spermiogenesis in Caenorhabditis elegans. Dev Cell 2021; 56:1631-1645.e7. [PMID: 34051143 DOI: 10.1016/j.devcel.2021.05.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 03/08/2021] [Accepted: 05/06/2021] [Indexed: 10/21/2022]
Abstract
Spermiogenesis in nematodes is a process whereby round and quiescent spermatids differentiate into asymmetric and crawling spermatozoa. The molecular mechanism underlying this symmetry breaking remains uncharacterized. In this study, we revealed that sperm-specific Na+/K+-ATPase (NKA) is evenly distributed on the plasma membrane (PM) of Caenorhabditis elegans spermatids but is translocated to and subsequently enters the invaginated membrane of the spermatozoa cell body during sperm activation. The polarization of NKA depends on the transport of cholesterol from the PM to membranous organelles (MOs) via membrane contact sites (MCSs). The inositol 5-phosphatase CIL-1 and the MO-localized PI4P phosphatase SAC-1 may mediate PI4P metabolism to drive cholesterol countertransport via sterol/lipid transport proteins through MCSs. Furthermore, the NKA function is required for C. elegans sperm motility and reproductive success. Our data imply that the lipid dynamics mediated by MCSs might play crucial roles in the establishment of cell polarity. eGraphical abstract.
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Affiliation(s)
- Qiushi Wang
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zheng Cao
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
| | - Baochen Du
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qi Zhang
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lianwan Chen
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Xia Wang
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhiheng Yuan
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peng Wang
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ruijun He
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Jin Shan
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanmei Zhao
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
| | - Long Miao
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Center for Biological Imaging, Core Facilities for Protein Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
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3
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Sharifian Gh M. Recent Experimental Developments in Studying Passive Membrane Transport of Drug Molecules. Mol Pharm 2021; 18:2122-2141. [PMID: 33914545 DOI: 10.1021/acs.molpharmaceut.1c00009] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The ability to measure the passive membrane permeation of drug-like molecules is of fundamental biological and pharmaceutical importance. Of significance, passive diffusion across the cellular membranes plays an effective role in the delivery of many pharmaceutical agents to intracellular targets. Hence, approaches for quantitative measurement of membrane permeability have been the topics of research for decades, resulting in sophisticated biomimetic systems coupled with advanced techniques. In this review, recent developments in experimental approaches along with theoretical models for quantitative and real-time analysis of membrane transport of drug-like molecules through mimetic and living cell membranes are discussed. The focus is on time-resolved fluorescence-based, surface plasmon resonance, and second-harmonic light scattering approaches. The current understanding of how properties of the membrane and permeant affect the permeation process is discussed.
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Affiliation(s)
- Mohammad Sharifian Gh
- Department of Cell Biology, University of Virginia, Charlottesville, Virginia 22908, United States
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4
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Zhang L, Gui T, Console L, Scalise M, Indiveri C, Hausler S, Kullak-Ublick GA, Gai Z, Visentin M. Cholesterol stimulates the cellular uptake of L-carnitine by the carnitine/organic cation transporter novel 2 (OCTN2). J Biol Chem 2020; 296:100204. [PMID: 33334877 PMCID: PMC7948396 DOI: 10.1074/jbc.ra120.015175] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 12/14/2020] [Accepted: 12/17/2020] [Indexed: 12/19/2022] Open
Abstract
The carnitine/organic cation transporter novel 2 (OCTN2) is responsible for the cellular uptake of carnitine in most tissues. Being a transmembrane protein OCTN2 must interact with the surrounding lipid microenvironment to function. Among the main lipid species that constitute eukaryotic cells, cholesterol has highly dynamic levels under a number of physiopathological conditions. This work describes how plasma membrane cholesterol modulates OCTN2 transport of L-carnitine in human embryonic kidney 293 cells overexpressing OCTN2 (OCTN2-HEK293) and in proteoliposomes harboring human OCTN2. We manipulated the cholesterol content of intact cells, assessed by thin layer chromatography, through short exposures to empty and/or cholesterol-saturated methyl-β-cyclodextrin (mβcd), whereas free cholesterol was used to enrich reconstituted proteoliposomes. We measured OCTN2 transport using [3H]L-carnitine, and expression levels and localization by surface biotinylation and Western blotting. A 20-min preincubation with mβcd reduced the cellular cholesterol content and inhibited L-carnitine influx by 50% in comparison with controls. Analogously, the insertion of cholesterol in OCTN2-proteoliposomes stimulated L-carnitine uptake in a dose-dependent manner. Carnitine uptake in cells incubated with empty mβcd and cholesterol-saturated mβcd to preserve the cholesterol content was comparable with controls, suggesting that the mβcd effect on OCTN2 was cholesterol dependent. Cholesterol stimulated L-carnitine influx in cells by markedly increasing the affinity for L-carnitine and in proteoliposomes by significantly enhancing the affinity for Na+ and, in turn, the L-carnitine maximal transport capacity. Because of the antilipogenic and antioxidant features of L-carnitine, the stimulatory effect of cholesterol on L-carnitine uptake might represent a novel protective effect against lipid-induced toxicity and oxidative stress.
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Affiliation(s)
- Lu Zhang
- College of Traditional Chinese Medicine, Innovation Research Institute of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China; Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Ting Gui
- College of Traditional Chinese Medicine, Innovation Research Institute of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Lara Console
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Arcavacata di Rende, Italy
| | - Mariafrancesca Scalise
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Arcavacata di Rende, Italy
| | - Cesare Indiveri
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Arcavacata di Rende, Italy
| | - Stephanie Hausler
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Gerd A Kullak-Ublick
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Zurich, Switzerland; Mechanistic Safety, CMO & Patient Safety, Global Drug Development, Novartis Pharma, Basel, Switzerland
| | - Zhibo Gai
- College of Traditional Chinese Medicine, Innovation Research Institute of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China; Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
| | - Michele Visentin
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
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5
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Michael OS, Dibia CL, Adeyanju OA, Olaniyi KS, Areola ED, Olatunji LA. Estrogen-progestin oral contraceptive and nicotine exposure synergistically confers cardio-renoprotection in female Wistar rats. Biomed Pharmacother 2020; 129:110387. [PMID: 32540646 DOI: 10.1016/j.biopha.2020.110387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 06/04/2020] [Accepted: 06/07/2020] [Indexed: 10/24/2022] Open
Abstract
Approximately fifty percent of premenopausal women who smoke cigarettes or on nicotine replacement therapy are also on hormonal contraceptives, especially oral estrogen-progestin. Oral estrogen-progestin therapy has been reported to promote insulin resistance (IR) which causes lipid influx into non-adipose tissue and impairs Na+/K+ -ATPase activity, especially in the heart and kidney. However, the effects of nicotine on excess lipid and altered Na+/K+ -ATPase activity associated with the use of estrogen-progestin therapy have not been fully elucidated. This study therefore aimed at investigating the effect of nicotine on cardiac and renal lipid influx and Na+/K+ -ATPase activity during estrogen-progestin therapy. Twenty-four female Wistar rats grouped into 4 (n = 6/group) received (p.o.) vehicle, nicotine (1.0 mg/kg) with or without estrogen-progestin steroids (1.0 μg ethinyl estradiol and 5.0 μg levonorgestrel) and estrogen-progestin only daily for 6 weeks. Data showed that estrogen-progestin treatment or nicotine exposure caused IR, hyperinsulinemia, increased cardiac and renal uric acid, malondialdehyde, triglyceride, glycogen synthase kinase-3, plasminogen activator inhibitor-1, reduced bilirubin and circulating estradiol. Estrogen-progestin treatment led to decreased cardiac Na+/K+-ATPase activity while nicotine did not alter Na+/K+-ATPase activity but increased plasma and tissue cotinine. Renal Na+/K+-ATPase activity was not altered by the treatments. However, all these alterations were reversed following combined administration of oral estrogen-progestin therapy and nicotine. The present study therefore demonstrates that oral estrogen-progestin therapy and nicotine exposure synergistically prevents IR-linked cardio-renotoxicity with corresponding improvement in cardiac and renal lipid accumulation, oxidative stress, inflammation and Na+/K+-ATPase activity.
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Affiliation(s)
- O S Michael
- Cardiometabolic Research Unit, Department of Physiology, College of Health Sciences, Bowen University, Iwo, Nigeria; HOPE Cardiometabolic Research Team, Department of Physiology, University of Ilorin, Ilorin, Nigeria.
| | - C L Dibia
- HOPE Cardiometabolic Research Team, Department of Physiology, University of Ilorin, Ilorin, Nigeria; Department of Physiology, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria
| | - O A Adeyanju
- HOPE Cardiometabolic Research Team, Department of Physiology, University of Ilorin, Ilorin, Nigeria; Department of Physiology, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, 360101, Nigeria
| | - K S Olaniyi
- HOPE Cardiometabolic Research Team, Department of Physiology, University of Ilorin, Ilorin, Nigeria; Department of Physiology, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, 360101, Nigeria
| | - E D Areola
- HOPE Cardiometabolic Research Team, Department of Physiology, University of Ilorin, Ilorin, Nigeria
| | - L A Olatunji
- HOPE Cardiometabolic Research Team, Department of Physiology, University of Ilorin, Ilorin, Nigeria
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6
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Pinheiro IRR, Melo MFN, de Sousa SV, Cardoso BG, da Silva TM, Rangel LP, Cortes VF, de Lima Santos H, Chaves VE, Garcia IJP, Barbosa LA. Evaluation of the effect of cafeteria diet on the kidney Na,K-ATPase activity, and oxidative stress. J Cell Biochem 2019; 120:19052-19063. [PMID: 31265167 DOI: 10.1002/jcb.29228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 06/04/2019] [Indexed: 11/07/2022]
Abstract
In this study, renal tissue, subdivided into the cortex and medulla of Wistar rats subjected to a cafeteria diet (CAF) for 24 days or to normal diet, was used to analyze whether the renal enzyme Na,K-ATPase activity was modified by CAF diet, as well as to analyze the α1 subunit of renal Na,K-ATPase expression levels. The lipid profile of the renal plasma membrane and oxidative stress were verified. In the Na,K-ATPase activity evaluation, no alteration was found, but a significant decrease of 30% in the cortex was detected in the α1 subunit expression of the enzyme. There was a 24% decrease in phospholipids in the cortex of rats submitted to CAF, a 17% increase in cholesterol levels in the cortex, and a 23% decrease in the medulla. Lipid peroxidation was significantly increased in the groups submitted to CAF, both in the cortical region, 29%, and in the medulla, 35%. Also, a reduction of 45% in the glutathione levels was observed in the cortex and medulla with CAF. CAF showed a nearly two-fold increase in glutathione peroxidase (GPX) activity in relation to the control group in the cortex and a 59% increase in the GPx activity in the medulla. In conclusion, although the diet was administered for a short period of time, important results were found, especially those related to the lipid profile and oxidative stress, which may directly affect renal function.
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Affiliation(s)
- Isadora Reis Restier Pinheiro
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
| | - Marina Fátima Nunes Melo
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
| | - Sarah Vivas de Sousa
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
| | - Bárbara Gatti Cardoso
- Laboratório de Fisiologia, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
| | - Thaís Marques da Silva
- Laboratório de Fisiologia, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
| | - Luciana Pereira Rangel
- Laboratório de Bioquímica Tumoral, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vanessa Faria Cortes
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil.,Laboratório de de Bioquímica de Membranas e ATPases, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
| | - Hérica de Lima Santos
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil.,Laboratório de de Bioquímica de Membranas e ATPases, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
| | - Valéria Ernestânia Chaves
- Laboratório de Fisiologia, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
| | - Israel José Pereira Garcia
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil.,Laboratório de de Bioquímica de Membranas e ATPases, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
| | - Leandro Augusto Barbosa
- Laboratório de Bioquímica Celular, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil.,Laboratório de de Bioquímica de Membranas e ATPases, Universidade Federal de São João del-Rei, Campus Centro-Oeste Dona Lindu, Divinópolis, Minas Gerais, Brazil
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7
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Garcia A, Lev B, Hossain KR, Gorman A, Diaz D, Pham THN, Cornelius F, Allen TW, Clarke RJ. Cholesterol depletion inhibits Na +,K +-ATPase activity in a near-native membrane environment. J Biol Chem 2019; 294:5956-5969. [PMID: 30770471 PMCID: PMC6463725 DOI: 10.1074/jbc.ra118.006223] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 02/08/2019] [Indexed: 12/28/2022] Open
Abstract
Cholesterol's effects on Na+,K+-ATPase reconstituted in phospholipid vesicles have been extensively studied. However, previous studies have reported both cholesterol-mediated stimulation and inhibition of Na+,K+-ATPase activity. Here, using partial reaction kinetics determined via stopped-flow experiments, we studied cholesterol's effect on Na+,K+-ATPase in a near-native environment in which purified membrane fragments were depleted of cholesterol with methyl-β-cyclodextrin (mβCD). The mβCD-treated Na+,K+-ATPase had significantly reduced overall activity and exhibited decreased observed rate constants for ATP phosphorylation (ENa3+ → E2P, i.e. phosphorylation by ATP and Na+ occlusion from the cytoplasm) and K+ deocclusion with subsequent intracellular Na+ binding (E2K2+ → E1Na3+). However, cholesterol depletion did not affect the observed rate constant for K+ occlusion by phosphorylated Na+,K+-ATPase on the extracellular face and subsequent dephosphorylation (E2P → E2K2+). Thus, partial reactions involving cation binding and release at the protein's intracellular side were most dependent on cholesterol. Fluorescence measurements with the probe eosin indicated that cholesterol depletion stabilizes the unphosphorylated E2 state relative to E1, and the cholesterol depletion-induced slowing of ATP phosphorylation kinetics was consistent with partial conversion of Na+,K+-ATPase into the E2 state, requiring a slow E2 → E1 transition before the phosphorylation. Molecular dynamics simulations of Na+,K+-ATPase in membranes with 40 mol % cholesterol revealed cholesterol interaction sites that differ markedly among protein conformations. They further indicated state-dependent effects on membrane shape, with the E2 state being likely disfavored in cholesterol-rich bilayers relative to the E1P state because of a greater hydrophobic mismatch. In summary, cholesterol extraction from membranes significantly decreases Na+,K+-ATPase steady-state activity.
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Affiliation(s)
- Alvaro Garcia
- From the School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia; The University of Sydney Nano Institute, Sydney, NSW 2006, Australia
| | - Bogdan Lev
- the School of Science, RMIT University, Melbourne, VIC 3001, Australia
| | - Khondker R Hossain
- From the School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia
| | - Amy Gorman
- From the School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia; the Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Dil Diaz
- From the School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia
| | | | - Flemming Cornelius
- the Department of Biomedicine, University of Aarhus, DK-8000 Aarhus C, Denmark
| | - Toby W Allen
- the School of Science, RMIT University, Melbourne, VIC 3001, Australia; the Department of Chemistry, University of California, Davis, California 95616
| | - Ronald J Clarke
- From the School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia; The University of Sydney Nano Institute, Sydney, NSW 2006, Australia.
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8
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Garcia IJP, Cézar JS, Lemos BS, Silva LN, Ribeiro RIMDA, Santana CC, Grillo LAM, Pinto FCH, Buzelle SL, Cortes VF, Santos HDL, Santos MESMD, Barbosa LA. Effects of high fat diet on kidney lipid content and the Na,K-ATPase activity. BRAZ J PHARM SCI 2018. [DOI: 10.1590/s2175-97902018000117165] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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9
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Günther G, Herlax V, Lillo MP, Sandoval-Altamirano C, Belmar LN, Sánchez SA. Study of rabbit erythrocytes membrane solubilization by sucrose monomyristate using laurdan and phasor analysis. Colloids Surf B Biointerfaces 2018; 161:375-385. [DOI: 10.1016/j.colsurfb.2017.10.068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 10/06/2017] [Accepted: 10/30/2017] [Indexed: 12/13/2022]
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10
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Cheng CY, Olijve LLC, Kausik R, Han S. Cholesterol enhances surface water diffusion of phospholipid bilayers. J Chem Phys 2015; 141:22D513. [PMID: 25494784 DOI: 10.1063/1.4897539] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Elucidating the physical effect of cholesterol (Chol) on biological membranes is necessary towards rationalizing their structural and functional role in cell membranes. One of the debated questions is the role of hydration water in Chol-embedding lipid membranes, for which only little direct experimental data are available. Here, we study the hydration dynamics in a series of Chol-rich and depleted bilayer systems using an approach termed (1)H Overhauser dynamic nuclear polarization (ODNP) NMR relaxometry that enables the sensitive and selective determination of water diffusion within 5-10 Å of a nitroxide-based spin label, positioned off the surface of the polar headgroups or within the nonpolar core of lipid membranes. The Chol-rich membrane systems were prepared from mixtures of Chol, dipalmitoyl phosphatidylcholine and/or dioctadecyl phosphatidylcholine lipid that are known to form liquid-ordered, raft-like, domains. Our data reveal that the translational diffusion of local water on the surface and within the hydrocarbon volume of the bilayer is significantly altered, but in opposite directions: accelerated on the membrane surface and dramatically slowed in the bilayer interior with increasing Chol content. Electron paramagnetic resonance (EPR) lineshape analysis shows looser packing of lipid headgroups and concurrently tighter packing in the bilayer core with increasing Chol content, with the effects peaking at lipid compositions reported to form lipid rafts. The complementary capability of ODNP and EPR to site-specifically probe the hydration dynamics and lipid ordering in lipid membrane systems extends the current understanding of how Chol may regulate biological processes. One possible role of Chol is the facilitation of interactions between biological constituents and the lipid membrane through the weakening or disruption of strong hydrogen-bond networks of the surface hydration layers that otherwise exert stronger repulsive forces, as reflected in faster surface water diffusivity. Another is the concurrent tightening of lipid packing that reduces passive, possibly unwanted, diffusion of ions and water across the bilayer.
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Affiliation(s)
- Chi-Yuan Cheng
- Department of Chemistry and Biochemistry and Materials Research Laboratory, University of California, Santa Barbara, California 93106, USA
| | - Luuk L C Olijve
- Laboratory of Macromolecular and Organic Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands
| | - Ravinath Kausik
- Department of Chemistry and Biochemistry and Materials Research Laboratory, University of California, Santa Barbara, California 93106, USA
| | - Songi Han
- Department of Chemistry and Biochemistry and Materials Research Laboratory, University of California, Santa Barbara, California 93106, USA
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11
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Yoneda JS, Rigos CF, de Lourenço TFA, Sebinelli HG, Ciancaglini P. Na,K-ATPase reconstituted in ternary liposome: the presence of cholesterol affects protein activity and thermal stability. Arch Biochem Biophys 2014; 564:136-41. [PMID: 25286376 DOI: 10.1016/j.abb.2014.09.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Revised: 09/12/2014] [Accepted: 09/26/2014] [Indexed: 01/27/2023]
Abstract
Differential scanning calorimetry (DSC) was applied to investigate the effect of cholesterol on the thermotropic properties of the lipid membrane (DPPC and DPPE). The thermostability and unfolding of solubilized and reconstituted Na,K-ATPase in DPPC:DPPE:cholesterol-liposomes was also studied to gain insight into the role of cholesterol in the Na,K-ATPase modulation of enzyme function and activity. The tertiary system (DPPC:DPPE:cholesterol) (molar ratio DPPC:DPPE equal 1:1) when cholesterol content was increased from 0% up to 40% results in a slight decrease in the temperature of transition and enthalpy, and an increase in width. We observed that, without heating treatment, at 37°C, the activity was higher for 20mol% cholesterol. However, thermal inactivation experiments showed that the enzyme activity loss time depends on the cholesterol membrane content. The unfolding of the enzyme incorporated to liposomes of DPPC:DPPE (1:1mol) with different cholesterol contents, ranging from 0% to 40% mol was also studied by DSC. Some differences between the thermograms indicate that the presence of lipids promotes a conformational change in protein structure and this change is enough to change the way Na,K-ATPase thermally unfolds.
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Affiliation(s)
- Juliana Sakamoto Yoneda
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto - FFCLRP-USP, Depto. Química, 14040-901 Ribeirão Preto, SP, Brazil
| | - Carolina Fortes Rigos
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto - FFCLRP-USP, Depto. Química, 14040-901 Ribeirão Preto, SP, Brazil
| | | | - Heitor Gobbi Sebinelli
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto - FFCLRP-USP, Depto. Química, 14040-901 Ribeirão Preto, SP, Brazil
| | - Pietro Ciancaglini
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto - FFCLRP-USP, Depto. Química, 14040-901 Ribeirão Preto, SP, Brazil.
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12
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Soto-Arriaza M, Olivares-Ortega C, Quina F, Aguilar L, Sotomayor C. Effect of cholesterol content on the structural and dynamic membrane properties of DMPC/DSPC large unilamellar bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:2763-9. [DOI: 10.1016/j.bbamem.2013.07.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 07/02/2013] [Accepted: 07/31/2013] [Indexed: 12/15/2022]
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13
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Venegas B, Zhu W, Haloupek NB, Lee J, Zellhart E, Sugár IP, Kiani MF, Chong PLG. Cholesterol superlattice modulates CA4P release from liposomes and CA4P cytotoxicity on mammary cancer cells. Biophys J 2012; 102:2086-94. [PMID: 22824272 DOI: 10.1016/j.bpj.2012.03.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 03/22/2012] [Indexed: 01/08/2023] Open
Abstract
Liposomal drugs are a useful alternative to conventional drugs and hold great promise for targeted delivery in the treatment of many diseases. Most of the liposomal drugs on the market or under clinical trials include cholesterol as a membrane stabilizing agent. Here, we used liposomal CA4P, an antivascular drug, to demonstrate that cholesterol content can actually modulate the release and cytotoxicity of liposomal drugs in a delicate and predictable manner. We found that both the rate of the CA4P release from the interior aqueous compartment of the liposomes to the bulk aqueous phase and the extent of the drug's cytotoxicity undergo a biphasic variation, as large as 50%, with liposomal cholesterol content at the theoretically predicted C(r), e.g., 22.0, 22.2, 25.0, 33.3, 40.0, and 50.0 mol % cholesterol for maximal superlattice formation. It appears that at C(r), CA4P can be released from the liposomes more readily than at non-C(r), probably due to the increased domain boundaries between superlattice and nonsuperlattice regions, which consequently results in increased cytotoxicity. The idea that the increased domain boundaries at C(r) would facilitate the escape of molecules from membranes was further supported by the data of dehydroergosterol transfer from liposomes to MβCD. These results together show that the functional importance of sterol superlattice formation in liposomes can be propagated to distal targeted cells and reveal a new, to our knowledge, mechanism for how sterol content and membrane lateral organization can control the release of entrapped or embedded molecules in membranes.
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Affiliation(s)
- Berenice Venegas
- Department of Biochemistry, Temple University School of Medicine, Philadelphia, PA, USA
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14
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Large conductance, calcium- and voltage-gated potassium (BK) channels: regulation by cholesterol. Pharmacol Ther 2012; 135:133-50. [PMID: 22584144 DOI: 10.1016/j.pharmthera.2012.05.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 04/09/2012] [Indexed: 11/21/2022]
Abstract
Cholesterol (CLR) is an essential component of eukaryotic plasma membranes. CLR regulates the membrane physical state, microdomain formation and the activity of membrane-spanning proteins, including ion channels. Large conductance, voltage- and Ca²⁺-gated K⁺ (BK) channels link membrane potential to cell Ca²⁺ homeostasis. Thus, they control many physiological processes and participate in pathophysiological mechanisms leading to human disease. Because plasmalemma BK channels cluster in CLR-rich membrane microdomains, a major driving force for studying BK channel-CLR interactions is determining how membrane CLR controls the BK current phenotype, including its pharmacology, channel sorting, distribution, and role in cell physiology. Since both BK channels and CLR tissue levels play a pathophysiological role in human disease, identifying functional and structural aspects of the CLR-BK channel interaction may open new avenues for therapeutic intervention. Here, we review the studies documenting membrane CLR-BK channel interactions, dissecting out the many factors that determine the final BK current response to changes in membrane CLR content. We also summarize work in reductionist systems where recombinant BK protein is studied in artificial lipid bilayers, which documents a direct inhibition of BK channel activity by CLR and builds a strong case for a direct interaction between CLR and the BK channel-forming protein. Bilayer lipid-mediated mechanisms in CLR action are also discussed. Finally, we review studies of BK channel function during hypercholesterolemia, and underscore the many consequences that the CLR-BK channel interaction brings to cell physiology and human disease.
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15
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Ciancaglini P, Simão AMS, Bolean M, Millán JL, Rigos CF, Yoneda JS, Colhone MC, Stabeli RG. Proteoliposomes in nanobiotechnology. Biophys Rev 2012; 4:67-81. [PMID: 28510001 PMCID: PMC5418368 DOI: 10.1007/s12551-011-0065-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 12/22/2011] [Indexed: 01/08/2023] Open
Abstract
Proteoliposomes are systems that mimic lipid membranes (liposomes) to which a protein has been incorporated or inserted. During the last decade, these systems have gained prominence as tools for biophysical studies on lipid-protein interactions as well as for their biotechnological applications. Proteoliposomes have a major advantage when compared with natural membrane systems, since they can be obtained with a smaller number of lipidic (and protein) components, facilitating the design and interpretation of certain experiments. However, they have the disadvantage of requiring methodological standardization for incorporation of each specific protein, and the need to verify that the reconstitution procedure has yielded the correct orientation of the protein in the proteoliposome system with recovery of its functional activity. In this review, we chose two proteins under study in our laboratory to exemplify the steps necessary for the standardization of the reconstitution of membrane proteins in liposome systems: (1) alkaline phosphatase, a protein with a glycosylphosphatidylinositol anchor, and (2) Na,K-ATPase, an integral membrane protein. In these examples, we focus on the production of the specific proteoliposomes, as well as on their biochemical and biophysical characterization, with emphasis on studies of lipid-protein interactions. We conclude the chapter by highlighting current prospects of this technology for biotechnological applications, including the construction of nanosensors and of a multi-protein nanovesicular biomimetic to study the processes of initiation of skeletal mineralization.
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Affiliation(s)
- P Ciancaglini
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto da (FFCLRP), Universidade de São Paulo - USP, 14040-901, Ribeirão Preto, SP, Brazil.
| | - A M S Simão
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto da (FFCLRP), Universidade de São Paulo - USP, 14040-901, Ribeirão Preto, SP, Brazil
| | - M Bolean
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto da (FFCLRP), Universidade de São Paulo - USP, 14040-901, Ribeirão Preto, SP, Brazil
| | - J L Millán
- Sanford Children's Health Research Center, Sanford - Burnham Medical Research Institute, La Jolla, CA, USA
| | - C F Rigos
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto da (FFCLRP), Universidade de São Paulo - USP, 14040-901, Ribeirão Preto, SP, Brazil
| | - J S Yoneda
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto da (FFCLRP), Universidade de São Paulo - USP, 14040-901, Ribeirão Preto, SP, Brazil
| | - M C Colhone
- Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto da (FFCLRP), Universidade de São Paulo - USP, 14040-901, Ribeirão Preto, SP, Brazil
| | - R G Stabeli
- Centro de Estudos de Biomoléculas Aplicadas a Medicina, Núcleo de Saúde (NUSAU), Universidade Federal de Rondônia (UNIR), 76800-000, Porto Velho, RO, Brazil
- Fundação Oswaldo Cruz (Fiocruz-Rondonia), Ministério da Saúde, 76812-245, Porto Velho, RO, Brazil
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Manna M, Mukhopadhyay C. Cholesterol driven alteration of the conformation and dynamics of phospholamban in model membranes. Phys Chem Chem Phys 2011; 13:20188-98. [DOI: 10.1039/c1cp21793c] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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17
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Tajima N, Itokazu Y, Korpi ER, Somerharju P, Käkelä R. Activity of BK(Ca) channel is modulated by membrane cholesterol content and association with Na+/K+-ATPase in human melanoma IGR39 cells. J Biol Chem 2010; 286:5624-38. [PMID: 21135099 DOI: 10.1074/jbc.m110.149898] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Interaction of large conductance Ca(2+)- and voltage-activated K(+) (BK(Ca)) channels with Na(+)/K(+)-ATPase, caveolin-1, and cholesterol was studied in human melanoma IGR39 cells. Functional BK(Ca) channels were enriched in caveolin-rich and detergent-resistant membranes, i.e. rafts, and blocking of the channels by a specific BK(Ca) blocker paxilline reduced proliferation of the cells. Disruption of rafts by selective depletion of cholesterol released BK(Ca) channels from these domains with a consequent increase in their activity. Consistently, cholesterol enrichment of the cells increased the proportion of BK(Ca) channels in rafts and decreased their activity. Immunocytochemical analysis showed that BK(Ca) channels co-localize with Na(+)/K(+)-ATPase in a cholesterol-dependent manner, thus suggesting their co-presence in rafts. Supporting this, ouabain, a specific blocker of Na(+)/K(+)-ATPase, inhibited BK(Ca) whole-cell current markedly in control cells but not in cholesterol-depleted ones. This inhibition required the presence of external Na(+). Collectively, these data indicate that the presence of Na(+)/K(+)-ATPase in rafts is essential for efficient functioning of BK(Ca) channels, presumably because the pump maintains a low intracellular Na(+) proximal to the BK(Ca) channel. In conclusion, cholesterol could play an important role in cellular ion homeostasis and thus modulate many cellular functions and cell proliferation.
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Affiliation(s)
- Nobuyoshi Tajima
- Department of Medical Biochemistry and Developmental Biology, Institute of Biomedicine, University of Helsinki, Helsinki FI-00014, Finland
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18
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Chong PLG, Zhu W, Venegas B. On the lateral structure of model membranes containing cholesterol. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2009; 1788:2-11. [DOI: 10.1016/j.bbamem.2008.10.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2008] [Revised: 10/18/2008] [Accepted: 10/20/2008] [Indexed: 10/21/2022]
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19
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Sterol superlattice affects antioxidant potency and can be used to assess adverse effects of antioxidants. Anal Biochem 2008; 382:1-8. [DOI: 10.1016/j.ab.2008.07.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2008] [Revised: 07/17/2008] [Accepted: 07/18/2008] [Indexed: 12/14/2022]
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20
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Somerharju P, Virtanen JA, Cheng KH, Hermansson M. The superlattice model of lateral organization of membranes and its implications on membrane lipid homeostasis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1788:12-23. [PMID: 19007747 DOI: 10.1016/j.bbamem.2008.10.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Revised: 10/10/2008] [Accepted: 10/10/2008] [Indexed: 01/10/2023]
Abstract
Most biological membranes are extremely complex structures consisting of hundreds of different lipid and protein molecules. According to the famous fluid-mosaic model lipids and many proteins are free to diffuse very rapidly in the plane of the membrane. While such fast diffusion implies that different membrane lipids would be laterally randomly distributed, accumulating evidence indicates that in model and natural membranes the lipid components tend to adopt regular (superlattice-like) distributions. The superlattice model, put forward based on such evidence, is intriguing because it predicts that 1) there is a limited number of allowed compositions representing local minima in membrane free energy and 2) those energy minima could provide set-points for enzymes regulating membrane lipid compositions. Furthermore, the existence of a discrete number of allowed compositions could help to maintain organelle identity in the face of rapid inter-organelle membrane traffic.
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Affiliation(s)
- Pentti Somerharju
- Institute of Biomedicine, Department of Medical Biochemistry, University of Helsinki, Finland.
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Venegas B, Sugár IP, Chong PLG. Critical factors for detection of biphasic changes in membrane properties at specific sterol mole fractions for maximal superlattice formation. J Phys Chem B 2007; 111:5180-92. [PMID: 17441759 DOI: 10.1021/jp070222k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Here we use the excitation generalized polarization (GPex) of 6-lauroyl-2-(dimethylamino)naphthalene (Laurdan) fluorescence in fluid cholesterol/1-palmitoyl-2-oleoyl-l-alpha-phosphatidylcholine large unilamellar vesicles to explore the experimental conditions that would be required in order to detect a biphasic change in membrane properties at specific sterol mole fractions (Cr) (e.g., 20.0, 22.2, 25.0, 33.3, 40.0, and 50.0 mol %) for maximal sterol superlattice formation. Laurdan's GPex changes with sterol content in an alternating manner, showing minima (termed as GPex dips) at approximately Cr. GPex dips are detectable if the vesicles are preincubated for a sufficient time period and protected from sterol oxidation. In most cases, vesicles with a higher lipid concentration take a longer time to show a GPex dip at Cr. The depth of the GPex dip increases with increasing incubation time and eventually reaches a plateau, at which the maximum area covered by superlattices is expected to be achieved. However, if the vesicles are not protected against sterol oxidation, the GPex dips are attenuated or obliterated. These effects can be attributed to the increased inter-bilayer lipid exchange and the increased vesicle-vesicle interactions present at high lipid (vesicle) concentrations as well as the decreased interactions between oxysterols and phospholipids. These possible explanations have been incorporated into a kinetic model that is able to calculate the effects of sterol oxidation and lipid concentration on the depth of the GPex dip. The depth of the GPex dip, the required incubation time for the dip formation, and the lipid concentration dependence of the GPex dip vary with Cr, suggesting different physical properties for different sterol superlattices. To detect a biphasic change in membrane properties at Cr, one should also use small sterol mole fraction increments over a wide range, keep all of the vesicles in the same sample set under the same thermal history, and consider lipid concentration, probe type, and Cr value. These results improve our mechanistic understanding of sterol superlattice formation and explain why some studies, especially those requiring high lipid concentrations, did not detect a biphasic change in membrane properties at Cr.
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Affiliation(s)
- Berenice Venegas
- Department of Biochemistry, Temple University School of Medicine, 3420 N. Broad St, Philadelphia, Pennsylvania 19140, USA
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