Effect of acute ozone induced airway inflammation on human sympathetic nerve traffic: a randomized, placebo controlled, crossover study

Jens Tank, Heike Biller, Karsten Heusser, Olaf Holz, André Diedrich, Theodor Framke, Armin Koch, Anika Grosshennig, Wolfgang Koch, Norbert Krug, Jens Jordan, Jens M Hohlfeld, Jens Tank, Heike Biller, Karsten Heusser, Olaf Holz, André Diedrich, Theodor Framke, Armin Koch, Anika Grosshennig, Wolfgang Koch, Norbert Krug, Jens Jordan, Jens M Hohlfeld

Abstract

Background: Ozone concentrations in ambient air are related to cardiopulmonary perturbations in the aging population. Increased central sympathetic nerve activity induced by local airway inflammation may be one possible mechanism.

Methodology/principal findings: To elucidate this issue further, we performed a randomized, double-blind, cross-over study, including 14 healthy subjects (3 females, age 22-47 years), who underwent a 3 h exposure with intermittent exercise to either ozone (250 ppb) or clean air. Induced sputum was collected 3 h after exposure. Nineteen to 22 hours after exposure, we recorded ECG, finger blood pressure, brachial blood pressure, respiration, cardiac output, and muscle sympathetic nerve activity (MSNA) at rest, during deep breathing, maximum-inspiratory breath hold, and a Valsalva maneuver. While the ozone exposure induced the expected airway inflammation, as indicated by a significant increase in sputum neutrophils, we did not detect a significant estimated treatment effect adjusted for period on cardiovascular measurements. Resting heart rate (clean air: 59±2, ozone 60±2 bpm), blood pressure (clean air: 121±3/71±2 mmHg; ozone: 121±2/71±2 mmHg), cardiac output (clean air: 7.42±0.29 mmHg; ozone: 7.98±0.60 l/min), and plasma norepinephrine levels (clean air: 213±21 pg/ml; ozone: 202±16 pg/ml), were similar on both study days. No difference of resting MSNA was observed between ozone and air exposure (air: 23±2, ozone: 23±2 bursts/min). Maximum MSNA obtained at the end of apnea (air: 44±4, ozone: 48±4 bursts/min) and during the phase II of the Valsalva maneuver (air: 64±5, ozone: 57±6 bursts/min) was similar.

Conclusions/significance: Our study suggests that acute ozone-induced airway inflammation does not increase resting sympathetic nerve traffic in healthy subjects, an observation that is relevant for environmental health. However, we can not exclude that chronic airway inflammation may contribute to sympathetic activation.

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1. Examples of integrated muscle sympathetic…
Figure 1. Examples of integrated muscle sympathetic nerve activity recorded at about 19–22 hours after exposure to clean air or to ozone in two subjects.
Figure 2. Individual values of muscle sympathetic…
Figure 2. Individual values of muscle sympathetic nerve activity (burst frequency in bursts/min) measured after clean air and ozone exposure at rest (top), at the end of maximum inspiratory apnea (middle) and during late phase II of the Valsalva maneuver (bottom) for subjects exposed first to clean air (empty circles, n = 4) and for subjects exposed first to ozone (filled circles, n = 7).

References

    1. World Health Organisation World Health Report: reducing risks and promoting healthy life. Geneva: World Health Organisation; 2002.
    1. Pope CA, III, Burnett RT, Thurston GD, Thun MJ, Calle EE, et al. Cardiovascular mortality and long-term exposure to particulate air pollution: epidemiological evidence of general pathophysiological pathways of disease. Circulation. 2004;109(1):71–77.
    1. Jerrett M, Burnett RT, Pope CA, III, Ito K, Thurston G, et al. Long-term ozone exposure and mortality. N Engl J Med. 2009;360(11):1085–1095.
    1. Kim CS, Alexis NE, Rappold AG, Kehrl H, Hazucha MJ, et al. Lung Function and Inflammatory Responses in Healthy Young Adults Exposed to 0.06 ppm Ozone for 6.6 Hours. Am J Respir Crit Care Med. 2011 [Epub ahead of print]
    1. Liu L, Poon R, Chen L, Frescura AM, Montuschi P, et al. Acute effects of air pollution on pulmonary function, airway inflammation, and oxidative stress in asthmatic children. Environ Health Perspect. 2009;117(4):668–674.
    1. Thayer JF, Yamamoto SS, Brosschot JF. The relationship of autonomic imbalance, heart rate variability and cardiovascular disease risk factors. Int J Cardiol. 2010;141(2):122–131.
    1. Chuang KJ, Chan CC, Su TC, Lee CT, Tang CS. The effect of urban air pollution on inflammation, oxidative stress, coagulation, and autonomic dysfunction in young adults. Am J Respir Crit Care Med. 2007;176(4):370–376.
    1. Park SK, O'Neill MS, Vokonas PS, Sparrow D, Schwartz J. Effects of air pollution on heart rate variability: the VA normative aging study. Environ Health Perspect. 2005;113(3):304–309.
    1. Gold DR, Litonjua A, Schwartz J, Lovett E, Larson A, et al. Ambient pollution and heart rate variability. Circulation. 2000;101(11):1267–1273.
    1. Power KL, Balmes J, Solomon C. Controlled exposure to combined particles and ozone decreases heart rate variability. J Occup Environ Med. 2008;50(11):1253–1260.
    1. Luttmann-Gibson H, Suh HH, Coull BA, Dockery DW, Sarnat SE, et al. Short-term effects of air pollution on heart rate variability in senior adults in Steubenville, Ohio. J Occup Environ Med. 2006;48(8):780–788.
    1. Fakhri AA, Ilic LM, Wellenius GA, Urch B, Silverman F, et al. Autonomic effects of controlled fine particulate exposure in young healthy adults: effect modification by ozone. Environ Health Perspect. 2009;117(8):1287–1292.
    1. Ye S, Gamburd M, Mozayeni P, Koss M, Campese VM. A limited renal injury may cause a permanent form of neurogenic hypertension. Am J Hypertens. 1998;(6 Pt 1):723–728.
    1. Ordway GA, Boheler KR, Longhurst JC. Stimulating intestinal afferents reflexly activates cardiovascular system in cats. Am J Physiol. 1988;254(2 Pt 2):H354–H360.
    1. Holz O, Tal-Singer R, Kanniess F, Simpson KJ, Gibson A, et al. Validation of the human ozone challenge model as a tool for assessing anti-inflammatory drugs in early development. J Clin Pharmacol. 2005;45(5):498–503.
    1. Bernardi L, Casucci G, Haider T, Brandstatter E, Pocecco E, et al. Autonomic and cerebrovascular abnormalities in mild COPD are worsened by chronic smoking. Eur Respir J. 2008;32(6):1458–1465.
    1. Kumar M, Verma NS, Tiwari S, Pandey US. Sympathetic hyperactivity in patients of bronchial asthma. Indian J Physiol Pharmacol. 2005;49(1):89–94.
    1. Holz O, Jorres RA, Timm P, Mucke M, Richter K, et al. Ozone-induced airway inflammatory changes differ between individuals and are reproducible. Am J Respir Crit Care Med. 1999;159(3):776–784.
    1. Holz O, Richter K, Jorres RA, Speckin P, Mucke M, et al. Changes in sputum composition between two inductions performed on consecutive days. Thorax. 1998;53(2):83–86.
    1. Tank J, Schroeder C, Diedrich A, Szczech E, Haertter S, et al. Selective impairment in sympathetic vasomotor control with norepinephrine transporter inhibition. Circulation. 2003;107(23):2949–2954.
    1. Hirsch JA, Bishop B. Respiratory sinus arrhythmia in humans: how breathing pattern modulates heart rate. Am J Physiol. 1981;241(4):H620–H629.
    1. Heart rate variability. Standards of measurement, physiological interpretation, and clinical use. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. Eur Heart J. 17(3):354–381.
    1. Immink RV, van den Born BJ, van Montfrans GA, Koopmans RP, Karemaker JM, et al. Impaired cerebral autoregulation in patients with malignant hypertension. Circulation. 2004;110(15):2241–2245.
    1. Holz O, Mucke M, Paasch K, Bohme S, Timm P, et al. Repeated ozone exposures enhance bronchial allergen responses in subjects with rhinitis or asthma. Clin Exp Allergy. 2002;32(5):681–689.
    1. Djukanovic R, Sterk PJ, Fahy JV, Hargreave FE. Standardised methodology of sputum induction and processing. Eur Respir J Suppl. 2002; 37:1s–2s.
    1. Mudway IS, Kelly FJ. An investigation of inhaled ozone dose and the magnitude of airway inflammation in healthy adults. Am J Respir Crit Care Med. 2004;169(10):1089–1095.
    1. Sayk F, Vietheer A, Schaaf B, Wellhoener P, Weitz G, et al. Endotoxemia causes central downregulation of sympathetic vasomotor tone in healthy humans. Am J Physiol Regul Integr Comp Physiol. 2008;295(3):R891–R898.
    1. Stenfors N, Pourazar J, Blomberg A, Krishna MT, Mudway I, et al. Effect of ozone on bronchial mucosal inflammation in asthmatic and healthy subjects. Respir Med. 2002;96(5):352–358.
    1. Krishna MT, Madden J, Teran LM, Biscione GL, Lau LC, et al. Effects of 0.2 ppm ozone on biomarkers of inflammation in bronchoalveolar lavage fluid and bronchial mucosa of healthy subjects. Eur Respir J. 1998;11(6):1294–1300.
    1. Balmes JR, Aris RM, Chen LL, Scannell C, Tager IB, et al. Effects of ozone on normal and potentially sensitive human subjects. Part I: Airway inflammation and responsiveness to ozone in normal and asthmatic subjects. Res Rep Health Eff Inst. 1997;(78):1–37.
    1. Aris RM, Christian D, Hearne PQ, Kerr K, Finkbeiner WE, et al. Ozone-induced airway inflammation in human subjects as determined by airway lavage and biopsy. Am Rev Respir Dis. 1993;148(5):1363–1372.
    1. Krishna MT, Springall D, Meng QH, Withers N, Macleod D, et al. Effects of ozone on epithelium and sensory nerves in the bronchial mucosa of healthy humans. Am J Respir Crit Care Med. 1997;156(3 Pt 1):943–950.
    1. Coleridge JC, Coleridge HM, Schelegle ES, Green JF. Acute inhalation of ozone stimulates bronchial C-fibers and rapidly adapting receptors in dogs. J Appl Physiol. 1993;74(5):2345–2352.
    1. Fagius J, Wallin BG. Long-term variability and reproducibility of resting human muscle nerve sympathetic activity at rest, as reassessed after a decade. Clin Auton Res. 1993;3(3):201–205.
    1. Somers VK, Mark AL, Zavala DC, Abboud FM. Contrasting effects of hypoxia and hypercapnia on ventilation and sympathetic activity in humans. J Appl Physiol. 1989;67(5):2101–2106.
    1. Somers VK, Dyken ME, Clary MP, Abboud FM. Sympathetic neural mechanisms in obstructive sleep apnea. J Clin Invest. 1995;96(4):1897–1904.
    1. Grassi G, Facchini A, Trevano FQ, Dell'Oro R, Arenare F, et al. Obstructive sleep apnea-dependent and -independent adrenergic activation in obesity. Hypertension. 2005;46(2):321–325.
    1. Heindl S, Lehnert M, Criee CP, Hasenfuss G, Andreas S. Marked sympathetic activation in patients with chronic respiratory failure. Am J Respir Crit Care Med. 2001;164(4):597–601.
    1. Heusser K, Dzamonja G, Tank J, Palada I, Valic Z, et al. Cardiovascular regulation during apnea in elite divers. Hypertension. 2009;53(4):719–724.
    1. Hausberg M, Mark AL, Winniford MD, Brown RE, Somers VK. Sympathetic and vascular effects of short-term passive smoke exposure in healthy nonsmokers. Circulation. 1997;96(1):282–287.
    1. Narkiewicz K, van de Borne PJ, Hausberg M, Cooley RL, Winniford MD, et al. Cigarette smoking increases sympathetic outflow in humans. Circulation. 1998;98(6):528–534.
    1. Somers VK, Mark AL, Abboud FM. Interaction of baroreceptor and chemoreceptor reflex control of sympathetic nerve activity in normal humans. J Clin.Invest. 1991;87(6):1953–1957.
    1. Brook RD. Cardiovascular effects of air pollution. Clin Sci (Lond) 2008;115(6):175–187.
    1. Peters A, Perz S, Doring A, Stieber J, Koenig W, et al. Increases in heart rate during an air pollution episode. Am J Epidemiol. 1999;150(10):1094–1098.
    1. Park SK, O'Neill MS, Vokonas PS, Sparrow D, Schwartz J. Effects of air pollution on heart rate variability: the VA normative aging study. Environ Health Perspect. 2005;113(3):304–309.
    1. Holguin F, Tellez-Rojo MM, Hernandez M, Cortez M, Chow JC, et al. Air pollution and heart rate variability among the elderly in Mexico City. Epidemiology. 2003;14(5):521–527.
    1. Urch B, Silverman F, Corey P, Brook JR, Lukic KZ, et al. Acute blood pressure responses in healthy adults during controlled air pollution exposures. Environ Health Perspect. 2005;113(8):1052–1055.

Source: PubMed

3
Prenumerera