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Buffenstein R, Lewis KN, Gibney PA, Narayan V, Grimes KM, Smith M, Lin TD, Brown-Borg HM. Probing Pedomorphy and Prolonged Lifespan in Naked Mole-Rats and Dwarf Mice. Physiology (Bethesda) 2020; 35:96-111. [DOI: 10.1152/physiol.00032.2019] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Pedomorphy, maintenance of juvenile traits throughout life, is most pronounced in extraordinarily long-lived naked mole-rats. Many of these traits (e.g., slow growth rates, low hormone levels, and delayed sexual maturity) are shared with spontaneously mutated, long-lived dwarf mice. Although some youthful traits likely evolved as adaptations to subterranean habitats (e.g., thermolability), the nature of these intrinsic pedomorphic features may also contribute to their prolonged youthfulness, longevity, and healthspan.
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Affiliation(s)
| | | | - Patrick A. Gibney
- Calico Life Sciences LLC, South San Francisco, California
- Department of Food Science, College of Agriculture and Life Sciences, Stocking Hall, Cornell University, Ithaca, New York
| | - Vikram Narayan
- Calico Life Sciences LLC, South San Francisco, California
| | - Kelly M. Grimes
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Megan Smith
- Calico Life Sciences LLC, South San Francisco, California
| | - Tzuhua D. Lin
- Calico Life Sciences LLC, South San Francisco, California
| | - Holly M. Brown-Borg
- Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota
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Xu J, Bartz TM, Chittoor G, Eiriksdottir G, Manichaikul AW, Sun F, Terzikhan N, Zhou X, Booth SL, Brusselle GG, de Boer IH, Fornage M, Frazier-Wood AC, Graff M, Gudnason V, Harris TB, Hofman A, Hou R, Houston DK, Jacobs Jr DR, Kritchevsky SB, Latourelle J, Lemaitre RN, Lutsey PL, Connor GO, Oelsner EC, Pankow JS, Psaty BM, Rohde RR, Rich SS, Rotter JI, Smith LJ, Stricker BH, Voruganti VS, Wang TJ, Zillikens MC, Barr RG, Dupuis J, Gharib SA, Lahousse L, London SJ, North KE, Smith AV, Steffen LM, Hancock DB, Cassano PA. Meta-analysis across Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium provides evidence for an association of serum vitamin D with pulmonary function. Br J Nutr 2018; 120:1159-1170. [PMID: 30205856 PMCID: PMC6263170 DOI: 10.1017/s0007114518002180] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)-pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D-pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (P race difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (P race difference=0·56). Among EA, the 25(OH)D-FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
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Affiliation(s)
- Jiayi Xu
- Division of Nutritional Sciences, Cornell University, Ithaca, New York, United States
| | - Traci M. Bartz
- Department of Biostatistics, University of Washington, Seattle, Washington, United States
- Cardiovascular Health Research Unit, University of Washington, Seattle, Washington, United States
| | - Geetha Chittoor
- Department of Biomedical and Translational Informatics, Geisinger, Danville, Pennsylvania, United States
- Gillings School of Global Public Health, Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States
| | | | - Ani W. Manichaikul
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, Virginia, United States
| | - Fangui Sun
- Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts, United States
| | - Natalie Terzikhan
- Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Xia Zhou
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, United States
| | - Sarah L. Booth
- Jean Mayer-U.S. Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, United States
| | - Guy G. Brusselle
- Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands
- Department of Respiratory Medicine, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Ian H. de Boer
- Department of Medicine, University of Washington, Seattle, Washington, United States
| | - Myriam Fornage
- Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, United States
- Human Genetics Center, School of Public Health, University of Texas Health Science Center at Houston, Houston, Texas, United States
| | - Alexis C. Frazier-Wood
- Children’s Nutrition Research Center, Baylor College of Medicine, Houston, Texas, United States
| | - Mariaelisa Graff
- Gillings School of Global Public Health, Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States
| | - Vilmundur Gudnason
- Icelandic Heart Association, Kopavogur, Iceland
- University of Iceland, Reykjavik, Iceland
| | - Tamara B. Harris
- Laboratory of Epidemiology, Demography, and Biometry, National Institute on Aging, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland, United States
| | - Albert Hofman
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands
- Netherlands Genomics Initiative (NGI)-sponsored Netherlands Consortium for Healthy Aging, Leiden, the Netherlands
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States
| | - Ruixue Hou
- Department of Nutrition and Nutrition Research Institute, University of North Carolina at Chapel Hill, Kannapolis, North Carolina, United States
| | - Denise K. Houston
- Sticht Center on Aging, Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, United State
| | - David R. Jacobs Jr
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, United States
| | - Stephen B. Kritchevsky
- Sticht Center on Aging, Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, United State
| | - Jeanne Latourelle
- The Pulmonary Center, Department of Medicine, Boston University, Boston, Massachusetts, United State
- Department of Neurology, Boston University, Boston, Massachusetts, United States
| | - Rozenn N. Lemaitre
- Cardiovascular Health Research Unit, University of Washington, Seattle, Washington, United States
- Department of Medicine, University of Washington, Seattle, Washington, United States
| | - Pamela L. Lutsey
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, United States
| | - George O. Connor
- The Pulmonary Center, Department of Medicine, Boston University, Boston, Massachusetts, United State
| | | | - James S. Pankow
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, United States
| | - Bruce M. Psaty
- Cardiovascular Health Research Unit, University of Washington, Seattle, Washington, United States
- Department of Medicine, University of Washington, Seattle, Washington, United States
- Department of Epidemiology, University of Washington, Seattle, Washington, United States
- Department of Health Services, University of Washington, Seattle, Washington, United States
- Kaiser Permanente Washington Health Research Institute, Seattle, Washington, United States
| | - Rebecca R. Rohde
- Gillings School of Global Public Health, Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States
| | - Stephen S. Rich
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, Virginia, United States
| | - Jerome I. Rotter
- Institute for Translational Genomics and Population Sciences, Los Angeles Biomedical Research Institute and Department of Pediatrics at Harbor-UCLA Medical Center, Torrance, California, United States
| | - Lewis J. Smith
- Division of Pulmonary and Critical Care, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States
| | - Bruno H. Stricker
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands
- Netherlands Genomics Initiative (NGI)-sponsored Netherlands Consortium for Healthy Aging, Leiden, the Netherlands
| | - V. Saroja Voruganti
- Department of Nutrition and Nutrition Research Institute, University of North Carolina at Chapel Hill, Kannapolis, North Carolina, United States
| | - Thomas J. Wang
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University, Nashville, Tennessee, United States
| | - M. Carola Zillikens
- Netherlands Genomics Initiative (NGI)-sponsored Netherlands Consortium for Healthy Aging, Leiden, the Netherlands
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands
| | - R. Graham Barr
- Department of Medicine, Columbia University, New York, New York, United States
| | - Josée Dupuis
- Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts, United States
| | - Sina A. Gharib
- Department of Medicine, University of Washington, Seattle, Washington, United States
- Center for Lung Biology, University of Washington, Seattle, Washington, United States
| | - Lies Lahousse
- Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands
- Department of Bioanalysis, Ghent University, Ghent, Belgium
| | - Stephanie J. London
- Division of Intramural Research, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, United States
| | - Kari E. North
- Gillings School of Global Public Health, Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States
| | - Albert V. Smith
- Icelandic Heart Association, Kopavogur, Iceland
- University of Iceland, Reykjavik, Iceland
| | - Lyn M. Steffen
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, United States
| | - Dana B. Hancock
- Behavioral and Urban Health Program, Behavioral Health and Criminal Justice Division, RTI International, Research Triangle Park, North Carolina, United States
| | - Patricia A. Cassano
- Division of Nutritional Sciences, Cornell University, Ithaca, New York, United States
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Tahedl D, Wirkes A, Tschanz SA, Ochs M, Mühlfeld C. How common is the lipid body-containing interstitial cell in the mammalian lung? Am J Physiol Lung Cell Mol Physiol 2014; 307:L386-94. [PMID: 24973404 DOI: 10.1152/ajplung.00131.2014] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Pulmonary lipofibroblasts are thought to be involved in lung development, regeneration, vitamin A storage, and surfactant synthesis. Most of the evidence for these important functions relies on mouse or rat studies. Therefore, the present study was designed to investigate the presence of lipofibroblasts in a variety of early postnatal and adult mammalian species (including humans) to evaluate the ability to generalize functions of this cell type for other species. For this purpose, lung samples from 14 adult mammalian species as well as from postnatal mice, rats, and humans were investigated using light and electron microscopic stereology to obtain the volume fraction and the total volume of lipid bodies. In adult animals, lipid bodies were observed only, but not in all rodents. In all other species, no lipofibroblasts were observed. In rodents, lipid body volume scaled with body mass with an exponent b = 0.73 in the power law equation. Lipid bodies were not observed in postnatal human lungs but showed a characteristic postnatal increase in mice and rats and persisted at a lower level in the adult animals. Among 14 mammalian species, lipofibroblasts were only observed in rodents. The great increase in lipid body volume during early postnatal development of the mouse lung confirms the special role of lipofibroblasts during rodent lung development. It is evident that the cellular functions of pulmonary lipofibroblasts cannot be transferred easily from rodents to other species, in particular humans.
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Affiliation(s)
- Daniel Tahedl
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - André Wirkes
- Institute of Anatomy and Cell Biology, Justus-Liebig-University Gießen, Gießen, Germany
| | | | - Matthias Ochs
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany; and Cluster of Excellence REBIRTH (From Regenerative Biology to Reconstructive Therapy), Hannover, Germany
| | - Christian Mühlfeld
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany; and Cluster of Excellence REBIRTH (From Regenerative Biology to Reconstructive Therapy), Hannover, Germany
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Wirkes A, Jung K, Ochs M, Mühlfeld C. Allometry of the mammalian intracellular pulmonary surfactant system. J Appl Physiol (1985) 2010; 109:1662-9. [DOI: 10.1152/japplphysiol.00674.2010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Alveolar epithelial (AE) surface area is closely correlated with body mass (BM) in mammals. The AE is covered by a surfactant layer produced by alveolar epithelial type II (AE2) cells. We hypothesized that the total number of AE2 cells and the volume of intracellular surfactant-storing lamellar bodies (Lb) are correlated with BM with a similar slope as AE surface area. We used light and electron microscopic stereology to estimate the number and mean volume of AE2 cells and the total volume of Lb in 12 mammalian species ranging from 2 to 3 g (Etruscan shrew) to 400–500 kg (horse) BM. The mean size of Lb was evaluated using the volume-weighted mean volume and the volume-to-surface ratio of Lb. The mean volume of AE2 cells was 500–600 μm3 in most species, but was higher in Etruscan shrew, guinea pig, and human lung. The mean volume of Lb per AE2 cell was 80–100 μm3 in most species, with the same exceptions as above. However, the total number of AE2 cells and the total volume of Lb were closely correlated with BM and exhibited an allometric relationship similar to the slope of AE surface area. The mean size of Lb was similar in all investigated species. In conclusion, the mean volume of AE2 cells and their Lb are independent of BM but show some interspecific variations. The adaptation of the intracellular surfactant pool size to BM is obtained by the variation of the number of AE2 cells in the lung.
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Affiliation(s)
- André Wirkes
- Institute of Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Kristina Jung
- Institute of Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Matthias Ochs
- Institute of Anatomy, University of Bern, Bern, Switzerland; and
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Christian Mühlfeld
- Institute of Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
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Kolb EM, Kelly SA, Middleton KM, Sermsakdi LS, Chappell MA, Garland T. Erythropoietin elevates VO2,max but not voluntary wheel running in mice. ACTA ACUST UNITED AC 2010; 213:510-9. [PMID: 20086137 DOI: 10.1242/jeb.029074] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Voluntary activity is a complex trait, comprising both behavioral (motivation, reward) and anatomical/physiological (ability) elements. In the present study, oxygen transport was investigated as a possible limitation to further increases in running by four replicate lines of mice that have been selectively bred for high voluntary wheel running and have reached an apparent selection limit. To increase oxygen transport capacity, erythrocyte density was elevated by the administration of an erythropoietin (EPO) analogue. Mice were given two EPO injections, two days apart, at one of two dose levels (100 or 300 microg kg(-1)). Hemoglobin concentration ([Hb]), maximal aerobic capacity during forced treadmill exercise (VO2,max) and voluntary wheel running were measured. [Hb] did not differ between high runner (HR) and non-selected control (C) lines without EPO treatment. Both doses of EPO significantly (P<0.0001) increased [Hb] as compared with sham-injected animals, with no difference in [Hb] between the 100 microg kg(-1) and 300 microg kg(-1) dose levels (overall mean of 4.5 g dl(-1) increase). EPO treatment significantly increased VO2,max by approximately 5% in both the HR and C lines, with no dosexline type interaction. However, wheel running (revolutions per day) did not increase with EPO treatment in either the HR or C lines, and in fact significantly decreased at the higher dose in both line types. These results suggest that neither [Hb] per se nor VO2,max is limiting voluntary wheel running in the HR lines. Moreover, we hypothesize that the decrease in wheel running at the higher dose of EPO may reflect direct action on the reward pathway of the brain.
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Affiliation(s)
- E M Kolb
- Department of Biology, University of California, Riverside, CA 92521, USA
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Turner DL, Hoppeler H, Hokanson J, Weibel ER. Cold acclimation and endurance training in guinea pigs: changes in daily and maximal metabolism. RESPIRATION PHYSIOLOGY 1995; 101:183-8. [PMID: 8570920 DOI: 10.1016/0034-5687(95)00022-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The physiological effects of training or cold acclimation on maximal oxygen uptake (VO2,max) and average daily metabolic rate (VO2,dav) of a small mammal, the guinea pig, are described. Young male guinea pigs were assigned to three experimental groups; control, endurance trained (70% VO2,max) or cold acclimated (5-7 degrees C) for six weeks. Measurements of VO2,max and VO2,dav were made before and after the treatments. VO2,max increased significantly in cold acclimated (+29%) and endurance trained (+23%) animals and was achieved at a higher maximal running speed compared to post-treatment controls. Maximal blood lactate concentration was significantly higher in cold acclimated compared to endurance trained animals. Endurance trained animals had a reduced VO2,dav compared to control animals, whereas cold acclimation raised VO2,dav in the cold as expected, but also at room temperature. All three groups showed a daily pattern in metabolic rate (night > day). In conclusion, both endurance training and cold acclimation lead to enhanced VO2,max and changes in resting oxygen consumption throughout the day.
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Affiliation(s)
- D L Turner
- Department of Anatomy, University of Bern, Switzerland
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Ross KA, Thurlbeck WM. Lung growth in newborn guinea pigs: effects of endurance exercise. RESPIRATION PHYSIOLOGY 1992; 89:353-64. [PMID: 1410848 DOI: 10.1016/0034-5687(92)90093-c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Newborn Hartley albino guinea pigs were exercised daily on a rodent treadmill at 25 m/min, 0 degree grade for a maximum of 1 1/2 h. Groups were exercised for 1, 2 and 3 weeks. Controls were age-matched sedentary animals. A separate group of animals was sacrificed after 12 h of life to establish baseline lung growth data. A morphological and biochemical comparison was made between the lungs of exercised and sedentary animals. No effect of exercise on lung growth was observed. After 2 weeks of exercise animals had diminished somatic growth compared to the controls. The data was pooled from exercised and control guinea pigs at 1 and 3 weeks, at which time there were no differences, in order to obtain normal growth data. The only change between 0 week and 1 week was a slight increase in femur length. Between 1 week (and also 0 week) and 3 weeks there were significant increases in lung volume, lung weight, protein content, inter-alveolar wall distance, mean chord length of alveoli and ducts, and gas exchanging surface area. The guinea pig lung is well alveolated at birth and there was no evidence of subsequent alveolar multiplication. Enlargement of airspaces suggested that lung growth was primarily brought about by dilation. The lack of alveolar multiplication following exercise may be due to the fact the alveoli are fully developed at birth.
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Affiliation(s)
- K A Ross
- Department of Academic Pathology, University of British Columbia, Vancouver, Canada
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Crofton KM, Knight T. Auditory deficits and motor dysfunction following iminodipropionitrile administration in the rat. Neurotoxicol Teratol 1991; 13:575-81. [PMID: 1779945 DOI: 10.1016/0892-0362(91)90040-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The behavioral effects of 3,3'-iminodipropionitrile (IDPN) were studied using reflex modification of the acoustic startle response and figure-eight maze activity. A number of experiments were conducted with separate groups of adult male Long-Evans hooded rats exposed to saline or 50-500 mg/kg IDPN for 3 consecutive days. Auditory thresholds (reflex modification), motor activity, and grip strength were measured 1 day, and 1, 3, and 9 weeks postdosing. Reflex inhibition was monitored daily, prior to, during, and for 7 days following exposure. Auditory thresholds for 5- and 40-kHz tones were elevated approximately 25 dB and 50 dB, respectively. The onset of this auditory dysfunction in the 200-mg/kg/day group, as demonstrated by a loss of reflex inhibition, was 2 days for the 40-kHz tone and 4 days for the 5-kHz tone. Motor activity was increased up to 400% in the 200-mg/kg group, whereas there was no alteration in hindlimb grip strength. These data demonstrate dosage- and time-dependent alterations in auditory and motor function following IDPN exposure.
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Affiliation(s)
- K M Crofton
- Neurotoxicology Division, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711
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Mallory GB, Chaney H, Mutich RL, Motoyama EK. Longitudinal changes in lung function during the first three years of premature infants with moderate to severe bronchopulmonary dysplasia. Pediatr Pulmonol 1991; 11:8-14. [PMID: 1923670 DOI: 10.1002/ppul.1950110103] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Bronchopulmonary dysplasia (BPD) is a chronic obstructive pulmonary disease of prematurely born infants following prolonged mechanical ventilation and oxygen therapy. Developmental changes in pulmonary function of children with BPD during their early years have been difficult to study. We longitudinally studied maximal expiratory flow-volume curves by the forced deflation technique in 11 infants who had previous tracheostomy with moderate to severe BPD. Patients were classified into: those who were mechanically ventilated for less than 5 months (Group A), and those who were ventilated for 10 or more months (Group B). At 6 months of age, forced vital capacity (FVC) was 28.1 and 25.5 mL/kg in Group A and B, respectively, significantly less than normal (41.8 mL/kg). The maximum expiratory flow at 25% FVC (MEF25) at 6 months of age was 6.9 and 8.1 mL.kg-1.s-1 in Group A and B, respectively, (predicted value, 39.2 mL.kg-1.s-1). FVC reached the normal range by 12 months of age in Group A, but remained lower until 36 months of age in Group B. MEF25 gradually increased in Group A, reaching 18.0 mL.kg-1.s-1 at 36 months of age, whereas in Group B it was severely decreased at the same age (3.5 mL.kg-1.s-1). More than 75% of the patients had airway hyperreactivity at all ages. We have demonstrated that in patients with moderate to severe BPD, vital capacity is moderately decreased, but catches up to normal levels by 36 months of age. In contrast, severe lower airway obstruction persists in all infants, although in those with moderate BPD gradual improvement is seen. These findings suggest that in BPD neither obstruction of the smaller intrathoracic airways nor bronchial hyperreactivity resolves during the first 3 years of life.
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Affiliation(s)
- G B Mallory
- Department of Pediatrics, Washington University School of Medicine, St. Louis Children's Hospital, Missouri 63110
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12
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Faridy EE, Sanii MR, Thliveris JA. Fetal lung growth: influence of maternal exposure to cold and exercise in rats. RESPIRATION PHYSIOLOGY 1989; 75:309-25. [PMID: 2717819 DOI: 10.1016/0034-5687(89)90040-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The consequences of maternal exposure to low ambient temperature and exercise on maternal and fetal lung growth and in particular on the relationship between the three gas exchange organs (lungs and placenta) were studied in albino rats. Pregnant rats were subjected to 10 degrees C ambient temperature or to daily 10 min swimming exercise beginning at day 3 or day 11 of pregnancy till day 21 when they were sacrificed. Maternal lung growth was assessed by measuring the lung weight, lung air volume and lung DNA content, and the fetal lung growth by lung DNA content. Comparisons were made in rats with litter sizes of 9-14. The major findings were as follows. Cold increased: (1) the maternal lung, liver, kidney and heart size, and fetal body weight, in both groups, but to a greater degree in rats exposed to cold at day 3; and (2) fetal lung DNA content in rats subjected to cold at late gestation. It abolished the relationship between maternal and fetal lung DNA content which exists in large litter size pregnancies. Exercise did not enlarge the maternal lungs; it decreased the placental weight and fetal lung DNA content and abolished the relationship between maternal and fetal lung DNA content in rats subjected to exercise at early gestation. Neither cold nor exercise had an effect on fetal lung maturation. It is postulated that reduction in fetal lung DNA content with maternal exercise may result from the effects of hypoxemia which may be the consequence of reduced uterine blood flow; and that abolition of normally existing direct relationship between maternal and fetal lung DNA content may be the outcome of the effects of alterations in metabolic and endocrine functions, in both the mother and the fetus, in response to cold temperature and exercise, offsetting the influence the growing maternal lung may have on fetal lung growth.
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Affiliation(s)
- E E Faridy
- Department of Physiology, University of Manitoba, Winnipeg, Canada
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Faridy EE, Bucher S, Sanii MR. Relationship between maternal and fetal lung growth. RESPIRATION PHYSIOLOGY 1988; 72:171-85. [PMID: 3375610 DOI: 10.1016/0034-5687(88)90004-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This study analyzes the relationship between the maternal and fetal lungs, in rats in relation to litter size, to determine whether the enlargement of maternal lung during pregnancy is concurrent with that of the fetal lung. Pregnant albino rats were sacrificed on gestation day 21 (term 22 days). Maternal lung growth was assessed by measuring the lung weight, lung air volume and lung DNA content, and the fetal lung growth by lung DNA content. The findings were as follows: (1) no differences were noted between the lungs of non-pregnant rats and pregnant rats with small litter size (1-4); (2) pregnant rats with large litter size (10-18) had larger lungs than rats with small litter size; (3) there was a direct relationship between cellularity (DNA content) of the fetal lung and maternal lung when the latter underwent a growth change during pregnancy; (4) no relationship in cellularity was found between the maternal lung and placenta nor between the fetal lung and placenta. The results suggest that factors or processes which regulate the growth and dictate the size of the maternal lung during pregnancy similarly influence the fetal lung.
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Affiliation(s)
- E E Faridy
- Department of Physiology, University of Manitoba, Winnipeg, Canada
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Faridy EE, Bucher S. Maternal lung growth in surgically reduced litter size pregnancy. RESPIRATION PHYSIOLOGY 1988; 72:187-93. [PMID: 3375611 DOI: 10.1016/0034-5687(88)90005-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In our previous study (Faridy et al., this issue) we observed that pregnant rats with large litter size have larger lungs than rats with small litter size. The present study was conducted to test the hypothesis that in large litter size pregnancy, the maternal lung may not enlarge if, during pregnancy, the large litter size of 11-18 is surgically reduced to a small litter size of 3. A laparotomy was performed in pregnant albino rats at gestation day 7 (R7) or 14 (R14), all fetuses except 3 were removed and the rats were sacrificed at gestation day 21 (term 22 days). Maternal lung growth was assessed by measuring lung weight, lung DNA content and lung air volume, and the fetal lung growth by lung DNA content. The results were then compared with control pregnant rats of large (11-18) and small (1-3) litter size. The findings were: (1) reduction of litter size hindered maternal lung enlargement; (2) the earlier in pregnancy the surgical reduction was performed the smaller was the maternal lung, such that control (11-18) greater than R14 greater than R7 = control (1-3); (3) fetuses of R14 rats had larger lungs per body weight than R7 rats; (4) oxygen consumption of sham-operated rats with large litter size was higher (by 8-12%) than R7 rats. The results suggest that enlargement of maternal lung during pregnancy is related to litter size and perhaps to VO2. The fact that R14 fetal lung is larger than that of R7, supports our previous notion (Faridy et al., this tissue) that factors regulating the maternal lung growth similarly influence the fetal lung.
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Affiliation(s)
- E E Faridy
- Department of Physiology, University of Manitoba, Winnipeg, Canada
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15
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Zinman R, Gaultier C. Maximal static pressures and lung volumes in young female swimmers. RESPIRATION PHYSIOLOGY 1986; 64:229-39. [PMID: 3704390 DOI: 10.1016/0034-5687(86)90044-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The postulate that lung volumes are increased in swimmers because of a training effect that increases maximal static pressures (Pmax) thus augmenting the ability to inflate and deflate the lung was examined by comparing 38 competitively trained female swimmers to 59 controls between 7 and 13 years of age. Maximal static pressures on inspiration and expiration were generated near residual volume (RV), at functional residual capacity (FRC) and near total lung capacity (TLC). Lung volumes were measured by body plethysmography. The expected increase in lung volumes was present in the swimmers and was most marked in the oldest subjects. However, training did not have the anticipated effect on Pmax. In the younger swimmers training was associated with an increase in Pmax, but in the older swimmers Pmax was actually decreased in comparison to controls. These findings suggest that training may directly enhance lung growth, since the changes in lung volume cannot be accounted for by increases in respiratory muscle strength.
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16
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Adkisson VT, Callas G. Morphometric changes in the lungs of rats following adrenalectomy supplemented by desiccated thyroid. Anat Rec (Hoboken) 1982; 203:147-56. [PMID: 7103121 DOI: 10.1002/ar.1092030113] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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17
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Thompson ME. Lung growth in response to altered metabolic demand in hamsters: influence of thyroid function and cold exposure. RESPIRATION PHYSIOLOGY 1980; 40:335-47. [PMID: 7444219 DOI: 10.1016/0034-5687(80)90033-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This study examines the relation between whole body O2 requirements and lung growth. 6-week-old hamsters were exposed to cold (5 degrees C) or injected with thyroid hormone. These treatments elevated O2 consumption by 26% over a 28-day period. Both alveolar surface area and total lung air volume were increased by approximately 25% in each group. Morphometric data suggest that lung enlargement was due to an increase in the number or complexity, rather than size of individual alveolar units. Further elevating O2 demand by increasing thyroid dosage did not enhance lung size beyond the level observed with the lowest dose used. Depressing metabolic rate with an antithyroid drug for four weeks had no effect on lung structure (in this animal model). Results indicate that in hamsters, increased physiologic O2 demand may be met to a certain extent by augmentation of the pulmonary diffusing surface.
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Gehr P, Sehovic S, Burri PH, Claassen H, Weibel ER. The lung of shrews: morphometric estimation of diffusion capacity. RESPIRATION PHYSIOLOGY 1980; 40:33-47. [PMID: 7394364 DOI: 10.1016/0034-5687(80)90003-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The lungs of 16 shrews from 8 species (Sorex minutus, Neomys fodiens, Suncus etruscus, Crocidura russula, C. juvenetae, C. poensis, C. flavescens, C. giffardi) ranging in body weight from 2.2 to 100 g were studied by morphometry in order to compare the structural diffusion capacity for oxygen. DL02, with the oxygen consumption, VO2, measured on the same animals. VO2 was determined by short term measurements using a respirometer. DLO2 was estimated morphometrically. Both parameters demonstrated good coincidence in their allometric behaviour, establishing further progress in structure-function relationship in the respiratory apparatus. Whereas VO2 as well as DLO2 of shrews with a body weight W greater than 5 g follow the same allometric function established for mammals in general, the values for shrews with W less than 5 g exhibit significantly higher values. It appears that the pulmonary gas exchange parenchyma of these smallest mammals is well suited to supply the organism with the comparatively high levels of O2 required by the high metabolic rates, exhibiting a structural adaptation of the lung to higher VO2.
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Gehr P, Hugonnaud C, Burri PH, Bachofen H, Weibel ER. Adaptation of the growing lung to increased Vo2: III. The effect of exposure to cold environment in rats. RESPIRATION PHYSIOLOGY 1978; 32:345-53. [PMID: 663447 DOI: 10.1016/0034-5687(78)90122-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This study was undertaken to further test the hypothesis that increased Vo2 operates as a stimulus for enhanced lung growth leading to a pulmonary diffusing capacity adapted to the body's O2 requirements. Vo2 was augmented by raising 4-week-old rats for 3 weeks at 11 degrees C ambient temperature, with controls kept at 24 degrees C; this led to an increase in Vo2 averaged over 24 h by 64%. In contrast to previous experiments with waltzing mice this regime did not affect body growth, as the final body weights were identical in both groups. In the cold-exposed rats the lung volume was larger by 24%, due to an increase by 26% in air volume (at about TLC), 13% in capillary blood volume and 19% in tissue volume. The alveolar and capillary surface areas were increased by 18%, and Dm and Dl by 17% and 21% respectively. It is concluded that the hypothesis of adaptation of pulmonary gas exchange capacity to increased Vo2 cannot be rejected. Whilst in previous experiments some doubts had to be retained as to the specificity of the stimulus, because of its rather marked effect on body weight, this reservation does not hold in this case. The structural modifications which lead to increased Dl in the various experimental models are discussed.
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Dempsey JA, Gledhill N, Reddan WG, Forster HV, Hanson PG, Claremont AD. Pulmonary adaptation to exercise: effects of exercise type and duration, chronic hypoxia and physical training. Ann N Y Acad Sci 1977; 301:243-61. [PMID: 270920 DOI: 10.1111/j.1749-6632.1977.tb38203.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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21
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Hugonnaud C, Gehr P, Weibel R, Burri PH. Adaptation of the growing lung to increased oxygen consumption. II. Morphometric analysis. RESPIRATION PHYSIOLOGY 1977; 29:1-10. [PMID: 557828 DOI: 10.1016/0034-5687(77)90112-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This paper is the second part of a study investigating the effect of increased O2 consumption on the lungs of growing animals. By means of injections of the drug IDPN (imino-betabeta'-dipropionitrile) hyperkinesia was permanently induced in white mice aged 3 weeks, thus increasing their Vo2 per gram body weight (= specific VO2) by 50%. 3 1/2 months later the lungs of these animals were fixed by standardized procedure, analysed by morphometric techniques and the results compared with those of control mice originating from the same litters. Whereas the specific weights (= weights per gram body weight) of various organs did not differ significantly in the two groups, the specific volume of the lungs fixed with standardized techniques was up by 23% in IDPN mice. The relative composotion of lung parenchyma was also altered: air space volume density was slightly but significantly reduced, whereas tissue and capillary volume densities were both increased by 15%. An analogous increase was detected in alveolar and capillary surface densities. These changes led to significantly higher specific capillary and tissue volumes, as well as higher specific gas exchange surface areas in DIPN mice. Therefore the morphometrically determined specific pulmonary diffusion capacity was increased by more than 40% in the IDPN-treated animals. The findings are compared with those hitherto reported, where a structural adaptation of the gas exchange apparatus to exercise or altered PO2 had been found. In view of our present knowledge of the postnatal lung growth the quantitative structural alterations found in this experiment indicate that the higher O2 requirements in IDPN mice induced an alteration in the septal morphology. This consisted in an augmentation of septal volume possibly due to a lengthening and corrugation of the intralveolar septa. This change is reflected by the increased alveolar surface area in IDPN mice and by the increase of the ratio Sa/Va estimating the air space surface complexity.
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