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Fahlman A. Cardiorespiratory adaptations in small cetaceans and marine mammals. Exp Physiol 2024; 109:324-334. [PMID: 37968859 PMCID: PMC10988691 DOI: 10.1113/ep091095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 10/25/2023] [Indexed: 11/17/2023]
Abstract
The dive response, or the 'master switch of life', is probably the most studied physiological trait in marine mammals and is thought to conserve the available O2 for the heart and brain. Although generally thought to be an autonomic reflex, several studies indicate that the cardiovascular changes during diving are anticipatory and can be conditioned. The respiratory adaptations, where the aquatic breathing pattern resembles intermittent breathing in land mammals, with expiratory flow exceeding 160 litres s-1 has been measured in cetaceans, and where exposure to extreme pressures results in alveolar collapse (atelectasis) and recruitment upon ascent. Cardiorespiratory coupling, where breathing results in changes in heart rate, has been proposed to improve gas exchange. Cardiorespiratory coupling has also been reported in marine mammals, and in the bottlenose dolphin, where it alters both heart rate and stroke volume. When accounting for this respiratory dependence on cardiac function, several studies have reported an absence of a diving-related bradycardia except during dives that exceed the duration that is fuelled by aerobic metabolism. This review summarizes what is known about the respiratory physiology in marine mammals, with a special focus on cetaceans. The cardiorespiratory coupling is reviewed, and the selective gas exchange hypothesis is summarized, which provides a testable mechanism for how breath-hold diving vertebrates may actively prevent uptake of N2 during routine dives, and how stress results in failure of this mechanism, which results in diving-related gas emboli.
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Affiliation(s)
- Andreas Fahlman
- Global Diving Research SLValenciaSpain
- Fundación Oceanogràfic de la Comunidad ValencianaValenciaSpain
- Kolmården Wildlife ParkKolmårdenSweden
- IFMLinköping UniversityLinköpingSweden
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2
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Brown NJ, Lin JS, Barron AE. Helical side chain chemistry of a peptoid-based SP-C analogue: Balancing structural rigidity and biomimicry. Biopolymers 2019; 110:e23277. [PMID: 30972750 DOI: 10.1002/bip.23277] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 03/15/2019] [Accepted: 03/18/2019] [Indexed: 01/21/2023]
Abstract
Surfactant protein C (SP-C) is an important constituent of lung surfactant (LS) and, along with SP-B, is included in exogenous surfactant replacement therapies for treating respiratory distress syndrome (RDS). SP-C's biophysical activity depends upon the presence of a rigid C-terminal helix, of which the secondary structure is more crucial to functionality than precise side-chain chemistry. SP-C is highly sequence-conserved, suggesting that the β-branched, aliphatic side chains of the helix are also important. Nonnatural mimics of SP-C were created using a poly-N-substituted glycine, or "peptoid," backbone. The mimics included varying amounts of α-chiral, aliphatic side chains and α-chiral, aromatic side chains in the helical region, imparting either biomimicry or structural rigidity. Biophysical studies confirmed that the peptoids mimicked SP-C's secondary structure and replicated many of its surface-active characteristics. Surface activity was optimized by incorporating both structurally rigid and biomimetic side chain chemistries in the helical region indicating that both characteristics are important for activity. By balancing these features in one mimic, a novel analogue was created that emulates SP-C's in vitro surface activity while overcoming many of the challenges related to natural SP-C. Peptoid-based analogues hold great potential for use in a synthetic, biomimetic LS formulation for treating RDS.
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Affiliation(s)
- Nathan J Brown
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois
| | - Jennifer S Lin
- Department of Bioengineering, Stanford University, Stanford, California
| | - Annelise E Barron
- Department of Bioengineering, Stanford University, Stanford, California
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3
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Pasamontes A, Aksenov AA, Schivo M, Rowles T, Smith CR, Schwacke LH, Wells RS, Yeates L, Venn-Watson S, Davis CE. Noninvasive Respiratory Metabolite Analysis Associated with Clinical Disease in Cetaceans: A Deepwater Horizon Oil Spill Study. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:5737-5746. [PMID: 28406294 DOI: 10.1021/acs.est.6b06482] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Health assessments of wild cetaceans can be challenging due to the difficulty of gaining access to conventional diagnostic matrices of blood, serum and others. While the noninvasive detection of metabolites in exhaled breath could potentially help to address this problem, there exists a knowledge gap regarding associations between known disease states and breath metabolite profiles in cetaceans. This technology was applied to the largest marine oil spill in U.S. history (The 2010 Deepwater Horizon oil spill in the Gulf of Mexico). An accurate analysis was performed to test for associations between the exhaled breath metabolome and sonographic lung abnormalities as well as hematological, serum biochemical, and endocrine hormone parameters. Importantly, metabolites consistent with chronic inflammation, such as products of lung epithelial cellular breakdown and arachidonic acid cascade metabolites were associated with sonographic evidence of lung consolidation. Exhaled breath condensate (EBC) metabolite profiles also correlated with serum hormone concentrations (cortisol and aldosterone), hepatobiliary enzyme levels, white blood cell counts, and iron homeostasis. The correlations among breath metabolites and conventional health measures suggest potential application of breath sampling for remotely assessing health of wild cetaceans. This methodology may hold promise for large cetaceans in the wild for which routine collection of blood and respiratory anomalies are not currently feasible.
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Affiliation(s)
- Alberto Pasamontes
- Mechanical and Aerospace Engineering, University of California , One Shields Avenue, Davis, California 95616, United States
| | - Alexander A Aksenov
- Mechanical and Aerospace Engineering, University of California , One Shields Avenue, Davis, California 95616, United States
| | - Michael Schivo
- Department of Internal Medicine, University of California , 4150 V Street, Suite 3400, Sacramento, California 95817, United States
- Center for Comparative Respiratory Biology and Medicine, University of California , Davis, California 95616, United States
| | - Teri Rowles
- Office of Protected Resources, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 1315 East West Highway, Silver Spring, Maryland 20910, United States
| | - Cynthia R Smith
- National Marine Mammal Foundation, 2240 Shelter Island Drive, Suite 200, San Diego, California 92106, United States
| | - Lori H Schwacke
- National Centers for Coastal Ocean Science, National Oceanic and Atmospheric Administration, 331 Fort Johnson Road, Charleston, South Carolina 29412, United States
| | - Randall S Wells
- Chicago Zoological Society's Sarasota Dolphin Research Program, c/o Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, Florida 34236, United States
| | - Laura Yeates
- National Marine Mammal Foundation, 2240 Shelter Island Drive, Suite 200, San Diego, California 92106, United States
| | - Stephanie Venn-Watson
- National Marine Mammal Foundation, 2240 Shelter Island Drive, Suite 200, San Diego, California 92106, United States
| | - Cristina E Davis
- Mechanical and Aerospace Engineering, University of California , One Shields Avenue, Davis, California 95616, United States
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4
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Orgeig S, Morrison JL, Daniels CB. Evolution, Development, and Function of the Pulmonary Surfactant System in Normal and Perturbed Environments. Compr Physiol 2015; 6:363-422. [PMID: 26756637 DOI: 10.1002/cphy.c150003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Surfactant lipids and proteins form a surface active film at the air-liquid interface of internal gas exchange organs, including swim bladders and lungs. The system is uniquely positioned to meet both the physical challenges associated with a dynamically changing internal air-liquid interface, and the environmental challenges associated with the foreign pathogens and particles to which the internal surface is exposed. Lungs range from simple, transparent, bag-like units to complex, multilobed, compartmentalized structures. Despite this anatomical variability, the surfactant system is remarkably conserved. Here, we discuss the evolutionary origin of the surfactant system, which likely predates lungs. We describe the evolution of surfactant structure and function in invertebrates and vertebrates. We focus on changes in lipid and protein composition and surfactant function from its antiadhesive and innate immune to its alveolar stability and structural integrity functions. We discuss the biochemical, hormonal, autonomic, and mechanical factors that regulate normal surfactant secretion in mature animals. We present an analysis of the ontogeny of surfactant development among the vertebrates and the contribution of different regulatory mechanisms that control this development. We also discuss environmental (oxygen), hormonal and biochemical (glucocorticoids and glucose) and pollutant (maternal smoking, alcohol, and common "recreational" drugs) effects that impact surfactant development. On the adult surfactant system, we focus on environmental variables including temperature, pressure, and hypoxia that have shaped its evolution and we discuss the resultant biochemical, biophysical, and cellular adaptations. Finally, we discuss the effect of major modern gaseous and particulate pollutants on the lung and surfactant system.
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Affiliation(s)
- Sandra Orgeig
- School of Pharmacy & Medical Sciences and Sansom Institute for Health Research, University of South Australia, Adelaide, Australia
| | - Janna L Morrison
- School of Pharmacy & Medical Sciences and Sansom Institute for Health Research, University of South Australia, Adelaide, Australia
| | - Christopher B Daniels
- School of Pharmacy & Medical Sciences and Sansom Institute for Health Research, University of South Australia, Adelaide, Australia
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Lock MC, McGillick EV, Orgeig S, Zhang S, McMillen IC, Morrison JL. Mature Surfactant Protein-B Expression by Immunohistochemistry as a Marker for Surfactant System Development in the Fetal Sheep Lung. J Histochem Cytochem 2015; 63:866-78. [PMID: 26297137 DOI: 10.1369/0022155415600201] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 07/21/2015] [Indexed: 11/22/2022] Open
Abstract
Evaluation of the number of type II alveolar epithelial cells (AECs) is an important measure of the lung's ability to produce surfactant. Immunohistochemical staining of these cells in lung tissue commonly uses antibodies directed against mature surfactant protein (SP)-C, which is regarded as a reliable SP marker of type II AECs in rodents. There has been no study demonstrating reliable markers for surfactant system maturation by immunohistochemistry in the fetal sheep lung despite being widely used as a model to study lung development. Here we examine staining of a panel of surfactant pro-proteins (pro-SP-B and pro-SP-C) and mature proteins (SP-B and SP-C) in the fetal sheep lung during late gestation in the saccular/alveolar phase of development (120, 130, and 140 days), with term being 150 ± 3 days, to identify the most reliable marker of surfactant producing cells in this species. Results from this study indicate that during late gestation, use of anti-SP-B antibodies in the sheep lung yields significantly higher cell counts in the alveolar epithelium than SP-C antibodies. Furthermore, this study highlights that mature SP-B antibodies are more reliable markers than SP-C antibodies to evaluate surfactant maturation in the fetal sheep lung by immunohistochemistry.
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Affiliation(s)
- Mitchell C Lock
- Early Origins of Adult Health Research Group, School of Pharmacy & Medical Sciences, Sansom Institute for Health Research, University of South Australia, Adelaide, SA, Australia (MCL,EVM,SZ,CMM,JLM)
| | - Erin V McGillick
- Early Origins of Adult Health Research Group, School of Pharmacy & Medical Sciences, Sansom Institute for Health Research, University of South Australia, Adelaide, SA, Australia (MCL,EVM,SZ,CMM,JLM),Molecular & Evolutionary Physiology of the Lung Laboratory, School of Pharmacy & Medical Sciences, Sansom Institute for Health Research, University of South Australia, Adelaide, SA, Australia (EVM,SO)
| | - Sandra Orgeig
- Molecular & Evolutionary Physiology of the Lung Laboratory, School of Pharmacy & Medical Sciences, Sansom Institute for Health Research, University of South Australia, Adelaide, SA, Australia (EVM,SO)
| | - Song Zhang
- Early Origins of Adult Health Research Group, School of Pharmacy & Medical Sciences, Sansom Institute for Health Research, University of South Australia, Adelaide, SA, Australia (MCL,EVM,SZ,CMM,JLM)
| | - I Caroline McMillen
- Early Origins of Adult Health Research Group, School of Pharmacy & Medical Sciences, Sansom Institute for Health Research, University of South Australia, Adelaide, SA, Australia (MCL,EVM,SZ,CMM,JLM)
| | - Janna L Morrison
- Early Origins of Adult Health Research Group, School of Pharmacy & Medical Sciences, Sansom Institute for Health Research, University of South Australia, Adelaide, SA, Australia (MCL,EVM,SZ,CMM,JLM)
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McGowen MR, Gatesy J, Wildman DE. Molecular evolution tracks macroevolutionary transitions in Cetacea. Trends Ecol Evol 2014; 29:336-46. [DOI: 10.1016/j.tree.2014.04.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 04/02/2014] [Accepted: 04/03/2014] [Indexed: 10/25/2022]
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Piscitelli MA, Raverty SA, Lillie MA, Shadwick RE. A review of cetacean lung morphology and mechanics. J Morphol 2013; 274:1425-40. [DOI: 10.1002/jmor.20192] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 06/25/2013] [Accepted: 08/05/2013] [Indexed: 12/20/2022]
Affiliation(s)
- Marina A. Piscitelli
- Department of Zoology; University of British Columbia; Vancouver British Columbia Canada V6T 1Z4
| | - Stephen A. Raverty
- Department of Zoology; University of British Columbia; Vancouver British Columbia Canada V6T 1Z4
- Division of Plant and Animal Health; British Columbia Ministry of Agriculture; Abbotsford British Columbia Canada V3G 2M3
| | - Margo A. Lillie
- Department of Zoology; University of British Columbia; Vancouver British Columbia Canada V6T 1Z4
| | - Robert E. Shadwick
- Department of Zoology; University of British Columbia; Vancouver British Columbia Canada V6T 1Z4
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Moura AE, Natoli A, Rogan E, Hoelzel AR. Evolution of Functional Genes in Cetaceans Driven by Natural Selection on a Phylogenetic and Population Level. Evol Biol 2012. [DOI: 10.1007/s11692-012-9215-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Lukovic D, Cruz A, Gonzalez-Horta A, Almlen A, Curstedt T, Mingarro I, Pérez-Gil J. Interfacial behavior of recombinant forms of human pulmonary surfactant protein SP-C. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:7811-7825. [PMID: 22530695 DOI: 10.1021/la301134v] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The behavior at air-liquid interfaces of two recombinant versions of human surfactant protein SP-C has been characterized in comparison with that of native palmitoylated SP-C purified from porcine lungs. Both native and recombinant proteins promoted interfacial adsorption of dipalmitoylphosphatidylcholine bilayers to a limited extent, but catalyzed very rapid formation of films from different lipid mixtures containing both zwitterionic and anionic phospholipids. Once at the interface, the recombinant variants exhibited compression-driven structural transitions, consistent with changes in the orientation of the deacylated N-terminal segment, which were not observed in the native protein. Compression isotherms of lipid/protein films suggest that the recombinant SP-C forms promote expulsion at high pressures of a higher number of lipid molecules per mole of protein than does native SP-C. A more dynamic conformation of the N-terminal segment in recombinant SP-C forms is likely also responsible for facilitating compression-driven condensation of domains in anionic phospholipid films as observed by epifluorescence microscopy. Finally, both native palmitoylated SP-C and the phenylalanine-containing recombinant versions facilitate similarly the repetitive compression-expansion dynamics of lipid/protein films, which were able to reach maximal surface pressures with practically no hysteresis along multiple quasi-static or dynamic cycles.
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Affiliation(s)
- Dunja Lukovic
- Department of Biochemistry and Molecular Biology, University of Valencia, Valencia, Spain
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Maina JN, West JB, Orgeig S, Foot NJ, Daniels CB, Kiama SG, Gehr P, Mühlfeld C, Blank F, Müller L, Lehmann A, Brandenberger C, Rothen-Rutishauser B. Recent advances into understanding some aspects of the structure and function of mammalian and avian lungs. Physiol Biochem Zool 2010; 83:792-807. [PMID: 20687843 DOI: 10.1086/652244] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Recent findings are reported about certain aspects of the structure and function of the mammalian and avian lungs that include (a) the architecture of the air capillaries (ACs) and the blood capillaries (BCs); (b) the pulmonary blood capillary circulatory dynamics; (c) the adaptive molecular, cellular, biochemical, compositional, and developmental characteristics of the surfactant system; (d) the mechanisms of the translocation of fine and ultrafine particles across the airway epithelial barrier; and (e) the particle-cell interactions in the pulmonary airways. In the lung of the Muscovy duck Cairina moschata, at least, the ACs are rotund structures that are interconnected by narrow cylindrical sections, while the BCs comprise segments that are almost as long as they are wide. In contrast to the mammalian pulmonary BCs, which are highly compliant, those of birds practically behave like rigid tubes. Diving pressure has been a very powerful directional selection force that has influenced phenotypic changes in surfactant composition and function in lungs of marine mammals. After nanosized particulates are deposited on the respiratory tract of healthy human subjects, some reach organs such as the brain with potentially serious health implications. Finally, in the mammalian lung, dendritic cells of the pulmonary airways are powerful agents in engulfing deposited particles, and in birds, macrophages and erythrocytes are ardent phagocytizing cellular agents. The morphology of the lung that allows it to perform different functions-including gas exchange, ventilation of the lung by being compliant, defense, and secretion of important pharmacological factors-is reflected in its "compromise design."
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Affiliation(s)
- J N Maina
- Department of Zoology, University of Johannesburg, Johannesburg, South Africa.
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Recent advances in alveolar biology: evolution and function of alveolar proteins. Respir Physiol Neurobiol 2010; 173 Suppl:S43-54. [PMID: 20433956 DOI: 10.1016/j.resp.2010.04.023] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 04/21/2010] [Accepted: 04/21/2010] [Indexed: 12/25/2022]
Abstract
This review is focused on the evolution and function of alveolar proteins. The lung faces physical and environmental challenges, due to changing pressures/volumes and foreign pathogens, respectively. The pulmonary surfactant system is integral in protecting the lung from these challenges via two groups of surfactant proteins - the small molecular weight hydrophobic SPs, SP-B and -C, that regulate interfacial adsorption of the lipids, and the large hydrophilic SPs, SP-A and -D, which are surfactant collectins capable of inhibiting foreign pathogens. Further aiding pulmonary host defence are non-surfactant collectins and antimicrobial peptides that are expressed across the biological kingdoms. Linking to the first symposium session, which emphasised molecular structure and biophysical function of surfactant lipids and proteins, this review begins with a discussion of the role of temperature and hydrostatic pressure in shaping the evolution of SP-C in mammals. Transitioning to the role of the alveolus in innate host defence we discuss the structure, function and regulation of antimicrobial peptides, the defensins and cathelicidins. We describe the recent discovery of novel avian collectins and provide evidence for their role in preventing influenza infection. This is followed by discussions of the roles of SP-A and SP-D in mediating host defence at the alveolar surface and in mediating inflammation and the allergic response of the airways. Finally we discuss the use of animal models of lung disease including knockouts to develop an understanding of the role of these proteins in initiating and/or perpetuating disease with the aim of developing new therapeutic strategies.
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Torday JS, Powell FL, Farmer CG, Orgeig S, Nielsen HC, Hall AJ. Leptin integrates vertebrate evolution: from oxygen to the blood-gas barrier. Respir Physiol Neurobiol 2010; 173 Suppl:S37-42. [PMID: 20096383 DOI: 10.1016/j.resp.2010.01.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Revised: 01/11/2010] [Accepted: 01/13/2010] [Indexed: 11/30/2022]
Abstract
The following are the proceedings of a symposium held at the Second International Congress for Respiratory Science in Bad Honnef, Germany. The goals of the symposium were to delineate the blood-gas barrier phenotype across vertebrate species; to delineate the interrelationship between the evolution of the blood-gas barrier, locomotion and metabolism; to introduce the selection pressures for the evolution of the surfactant system as a key to understanding the physiology of the blood-gas barrier; to introduce the lung lipofibroblast and its product, leptin, which coordinately regulates pulmonary surfactant, type IV collagen in the basement membrane and host defense, as the cell-molecular site of selection pressure for the blood-gas barrier; to drill down to the gene regulatory network(s) involved in leptin signaling and the blood-gas barrier phenotype; to extend the relationship between leptin and the blood-gas barrier to diving mammals.
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Affiliation(s)
- J S Torday
- Department of Pediatrics, University of California-Los Angeles, CA, USA.
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Abstract
Since the widespread use of exogenous lung surfactant to treat neonatal respiratory distress syndrome, premature infant survival and respiratory morbidity have dramatically improved. Despite the effectiveness of the animal-derived surfactant preparations, there still remain some concerns and difficulties associated with their use. This has prompted investigation into the creation of synthetic surfactant preparations. However, to date, no clinically used synthetic formulation is as effective as the natural material. This is largely because the previous synthetic formulations lacked analogues of the hydrophobic proteins of the lung surfactant system, SP-B and SP-C, which are critical functional constituents. As a result, recent investigation has turned toward the development of a new generation of synthetic, biomimetic surfactants that contain synthetic phospholipids along with a mimic of the hydrophobic protein portion of lung surfactant. In this Account, we detail our efforts in creating accurate mimics of SP-C for use in a synthetic surfactant replacement therapy. Despite SP-C's seemingly simple structure, the predominantly helical protein is extraordinarily challenging to work with given its extreme hydrophobicity and structural instability, which greatly complicates the creation of an effective SP-C analogue. Drawing inspiration from Nature, two promising biomimetic approaches have led to the creation of rationally designed biopolymers that recapitulate many of SP-C's molecular features. The first approach utilizes detailed SP-C structure-activity relationships and amino acid folding propensities to create a peptide-based analogue, SP-C33. In SP-C33, the problematic and metastable polyvaline helix is replaced with a structurally stable polyleucine helix and includes a well-placed positive charge to prevent aggregation. SP-C33 is structurally stable and eliminates the association propensity of the native protein. The second approach follows the same design considerations but makes use of a non-natural, poly-N-substituted glycine or "peptoid" scaffold to circumvent the difficulties associated with SP-C. By incorporating unique biomimetic side chains in a non-natural backbone, the peptoid mimic captures both SP-C's hydrophobic patterning and its helical secondary structure. Despite the differences in structure, both SP-C33 and the SP-C peptoid mimic capture many requisite features of SP-C. In a surfactant environment, these analogues also replicate many of the key surface activities necessary for a functional biomimetic surfactant therapy while overcoming the difficulties associated with the natural protein. With improved stability, greater production potential, and elimination of possible pathogenic contamination, these biomimetic surfactant formulations offer not only the potential to improve the treatment of respiratory distress syndrome but also the opportunity to treat other respiratory-related disorders.
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Affiliation(s)
- Nathan J. Brown
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
| | - Jan Johansson
- Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, the Biomedical Centre, SE-751 23 Uppsala, Sweden
| | - Annelise E. Barron
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
- Department of Bioengineering, Stanford University, 318 Campus Drive, Stanford, California 94305
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Rytkönen KT, Ryynänen HJ, Nikinmaa M, Primmer CR. Variable patterns in the molecular evolution of the hypoxia-inducible factor-1 alpha (HIF-1α) gene in teleost fishes and mammals. Gene 2008; 420:1-10. [DOI: 10.1016/j.gene.2008.04.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2008] [Accepted: 04/28/2008] [Indexed: 10/22/2022]
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Plasencia I, Baumgart F, Andreu D, Marsh D, Pérez-Gil J. Effect of acylation on the interaction of the N-Terminal segment of pulmonary surfactant protein SP-C with phospholipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:1274-82. [DOI: 10.1016/j.bbamem.2008.02.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 01/22/2008] [Accepted: 02/07/2008] [Indexed: 02/02/2023]
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