Acetaldehyde and hexanaldehyde from cultured white cells
- Hye-Won Shin†1, 3,
- Brandon J Umber†2,
- Simone Meinardi2,
- Szu-Yun Leu3,
- Frank Zaldivar3,
- Donald R Blake2Email author and
- Dan M Cooper1, 3Email author
© Shin et al; licensee BioMed Central Ltd. 2009
Received: 09 December 2008
Accepted: 29 April 2009
Published: 29 April 2009
Noninvasive detection of innate immune function such as the accumulation of neutrophils remains a challenge in many areas of clinical medicine. We hypothesized that granulocytes could generate volatile organic compounds.
To begin to test this, we developed a bioreactor and analytical GC-MS system to accurately identify and quantify gases in trace concentrations (parts per billion) emitted solely from cell/media culture. A human promyelocytic leukemia cell line, HL60, frequently used to assess neutrophil function, was grown in serum-free medium.
HL60 cells released acetaldehyde and hexanaldehyde in a time-dependent manner. The mean ± SD concentration of acetaldehyde in the headspace above the cultured cells following 4-, 24- and 48-h incubation was 157 ± 13 ppbv, 490 ± 99 ppbv, 698 ± 87 ppbv. For hexanaldehyde these values were 1 ± 0.3 ppbv, 8 ± 2 ppbv, and 11 ± 2 ppbv. In addition, our experimental system permitted us to identify confounding trace gas contaminants such as styrene.
This study demonstrates that human immune cells known to mimic the function of innate immune cells, like neutrophils, produce volatile gases that can be measured in vitro in trace amounts.
Beyond the abundant respiratory gas, carbon dioxide, living organisms produce a wide variety of volatile compounds. Gas-mediated signaling is common among plant-plant, fungus-plant, insect-plant, and bacteria-plant interactions [1–7], but far less is known about such processes in mammals. Among the more extensively studied gas mediators in mammals are nitric oxide (NO) [8–15], ammonia , carbonyl sulfide, ethanol/acetone, and methyl nitrate [17–19]. While the potential utility of exhaled gases as a noninvasive marker of disease and metabolism is clear, knowledge of the underlying source and determinants of exhaled gases remains limited in many cases.
One relatively poorly studied but potentially significant source of physiologically active biological gases is the circulating granulocyte. In this context, NO is illustrative of the types of problems encountered; despite evidence that NO metabolic mediators are activated in neutrophils [20–22], we are unaware of studies in which NO gas has been measured directly from neutrophils in vitro. Other than the gases involved directly in respiration, such as O2 and CO2 which exist naturally in high concentrations, most of the remaining gases of interest found in exhaled breath exist in concentrations so small that their accurate measurement is a challenge. A related difficulty in attempting to determine gases produced by cells in culture is the fabrication of bioreactors which can accomodate a sufficient number of cells and allow ready access to the culture medium and headspace for sampling gases. Recently, analysis of human breath exhalate and smell- based medical diagnostics have been an area of rapid development . Selected ion flow tube mass spectrometry (SIFT-MS), on-fibre derivatization solid-phase microextraction (derivatization/SPME) and gas chromatography mass spectrometry (GC-MS) are commonly used techniques to quantify trace amounts of volatile organic gases obtained either in exhaled human breath [17–19, 24–26], or from the headspace above lung cancer cell line culture .
Our group, a team including expertise in biomedical engineering, immunology, translational science, and trace gas chemistry has been successful in generating novel information about breath biomarkers relevant to diseases ranging from cystic fibrosis to diabetes [17–19], and is beginning to probe the mechanisms responsible for biological trace gases. In this study, we hypothesized that human immune cells in culture can generate detectable volatile organic compounds. HL60, a well-known promyelocytic human leukemia cell line was used as a model system in this study. The goals of the current study were twofold: 1) to develop a bioreactor suitable for collecting the headspace gas above cell/media culture; and 2) apply the techniques of trace gas analysis developed in the Blake-Rowland laboratory . The cells were grown in a limited, serum free medium as well as in fetal calf serum (often used in cell culture systems) in order to identify potentially confounding effects of gases likely evolved from the more complex media. A systematic approach was also used to determine contaminant gas signals (e.g., emanating from the medium, plastic culture ware, and ambient air) from signals whose source was the cells in culture.
The HL60 cells were grown in RPMI 1640 (Gibco Ltd., Carlsbad, California, USA) supplemented with 10% fetal bovine serum (FBS) in a 37°C incubator under 5% CO2. The cells were transferred to the serum free media (AIM-V, Gibco Ltd., Carlsbad, California, USA) for up to 48 hours prior to the experiment to remove any conflicting growth factors provided by the FBS. On the day of the experiment, 40 × 106 cells were added to 30 ml of fresh culture medium in Teflon vials (Nalgene, Rochester, New York, USA).
Headspace Gas Collection Equipment and Methods
The bioreactors were then placed in an incubator at 37°C for the desired amount of time. After incubation, 1/4" stainless steel flex tubing was used to connect the glass bioreactor to a stainless steel canister (Swagelok, Solon, OH) . The tubing was evacuated to 10-1 torr and then isolated and the evacuated canister's Swagelok metal bellows valve was opened. The Teflon stopcock to the bioreactor was opened and the system was allowed to equilibrate for one minute. The canister was then closed, thereby isolating and preserving a portion of the bioreactor's headspace.
Followiong sample collection the bioreactor was disassembled and the cells were immediately collected and counted. To minimize the confounding effects of trace gases in the ambient air or from the incubated plastic culture ware, ambient room air samples were collected during purging and transfer of the bioreactor's headspace. Plastic cell culture ware and the Teflon vials were also examined as potential sources of contamination.
Gas Chromatography-Mass Spectrometry
The analyses of the headspace gases and room samples were performed on the system previously developed by the Blake-Rowland Laboratory at UCI to measure trace atmospheric gases. A complete description of the GC parameters and analytical methods are fully discussed elsewhere . Briefly, a 233 cm3 (at STP) sample is cryogenically preconcentrated and injected into a multi-column/detector gas chromatography system. The system consists of three Hewlett-Packard 6890 gas chromatography (GC) units (Wilmington, Delaware, USA) with a combination of columns and detectors capable of separating and quantifying hundreds of gases, including but not limited to, nonmethane hydrocarbons (NMHC), alkyl nitrates and halocarbons in the ppm to ppq range (10-6–10-15). Nitrogen oxides, ammonia and hydrogen sulfide are not quantified with this analytical system. Preliminary identifications of the unknown signals were made using GC-MS ion fragmentation matching software (Agilent Technologies, Santa Clara, California, USA). Verification was obtained by injecting the headspace of pure compounds (diluted to ppb levels with purified UHP helium) to ensure the elution time matched that of the unknown. The mixing ratios of the oxygenates were determined using effective carbon numbers (ECN) and the linear response to carbon number of the FID, which is accurate to within 25% . Concentrations of CO2 in the bioreactors following incubation were determined using a separate gas chromatography system. Aliquots of the collected headspace gas were injected onto a Carbosphere 80/100 packed column output to a thermal conductivity detector (TCD).
Helium stripping was used in an attempt to purge less volatile gases from the cell culture media. After 48-h incubation, the headspace above the HL60 cells and the media was collected. The Teflon vial was removed from the bioreactor and the cells were collected and counted. The supernatant was poured into a new Teflon vial and placed back into a bioreactor. The headspace of the bioreactor was then flushed for 5 minutes with purified ultra high purity (UHP) helium (Matheson, Newark, California, USA). Helium was bubbled through the media and collected in an evacuated (10-2 Torr) 1.9 L stainless steel canister to a final pressure of 900 Torr. The procedure was repeated identically for the media-only condition.
Experiments were repeated at least three times for gas phase measurements. We applied a 2-way analysis of variance (ANOVA) to compare the gas component emitted at three incubation times (4- vs. 24- vs. 48-h) from different conditions of cell culture (media only, and HL60 cells). Data presented are mean ± standard deviation (SD) and the significance level was set at level 0.05. Multiple comparisons adjustment was applied using Bonferroni's method.
Among numerous headspace gases detected from the current HL60 study, acetaldehyde and hexanaldehyde were the only gases found in appreciable amounts from HL60 cells. In addition, no additional gases were observed when the media was stripped with helium. Although acetaldehyde and hexanaldehyde were diluted by the helium, they were still found in higher concentrations when stripped from the media in which the cells were cultured (531 ppbv and 6 ppbv, respectively) compared to the control media in which no cells were grown (126 ppbv and 2 ppbv, respectively).
HL60 cell viability decreased with incubation time. Percent survival for the HL60 cells was 93 ± 4%, 96 ± 4%, and 70 ± 6% for 4-, 24-, and 48-h incubations respectively.
To the best of our knowledge, the employed trace gas characterization system, including bioreactor, and the observed acetaldehyde and hexanaldehyde from HL60 culture have not been previously reported. We found that HL60 cells generate appreciable amounts of acetaldehyde and hexanaldehyde that could be detected in the headspace above the culture media. Moreover, the experimental procedure was refined so that reproducibility of gas profiles from the cells could be observed.
Acetaldehyde has previously been detected in the exhaled human breath , and in human lung cancer cell line cultures . The current study demonstrates that human white blood cell line, HL60 is also capable of producing acetaldehyde. When compared to the previously reported lung cancer cell line, SK-MES , HL60 produced similar amounts of acetaldehyde in the headspace (16-h 408 ± 191 ppbv; 24-h 490 ± 99 ppbv for 40 million of SK-MES and HL60, respectively). Until fairly recently, it was believed that acetaldehyde in human cells was produced predominately from hepatic ethanol metabolism by the enzyme alcohol dehydrogenase [32, 33]. Previous studies have demonstrated that human blood cells also metabolize ethanol to acetaldehyde or oxidize it further to acetate in an alcohol dehydrogenase-independent manner [34, 35]. Elegant work by Hazen and colleagues from about 10 years ago confirmed the ability of neutrophils to oxidize amino acids and produce aldehydes, a reaction requiring myeloperoxidase (MPO), hydrogen peroxide (H2O2), and chloride ion (Cl-) [36, 37]. Since HL60 cells have high myeloperoxidase protein expression and activity , this amino acid oxidation is likely an alternative pathway for the generation of acetaldehyde from at least HL60 cells.
Hexanaldehyde has previously been detected in the exhaled breath , bronchial lavage fluid following ozone exposure , and exhaled breath condensate of healthy human volunteers and chronic obstructive pulmonary disease (COPD) patients . Recently, elevated hexanaldehyde has been detected in whole blood from lung cancer patients compared to the healthy controls . However, a cellular source of hexanaldehyde has not been completely identified. Oxidation of omega-6 unsaturated fatty acids (i.e., linoleic acid, arachidonic acid) has been reported to generate hexanaldehyde in rat and human bronchial lining fluids, and is accepted as the most plausible cellular source of hexanaldehyde [39, 41–45]. As demonstrated by Babior and colleagues , human neutrophils are able to generate ozone as a part of their phagocyte activity. Thus, we speculate that part of the observed hexanladehyde from HL60 cells originates from the cellular reaction between cellular fatty acid and ozone.
With the exception of acetaldehyde and hexanaldehyde, all other gases quantified in the headspace of the HL60 cells were either near the detection limit of the GC-MS system, or were evolved solely from the media (i.e., pentanaldehyde). In addition, styrene was identified as a contaminant emanating from the plastic culture ware and was excluded (see Figure 6). Although the observed styrene was most likely associated with plastic culture ware, it is interesting that styrene can have biological origins [47, 48].
Helium stripping is a commonly used method to detect less volatile gases dissolved in media. The purpose of helium stripping in this study was to identify gases generated by HL60 cells that would not be present in the headspace because of low volatility. However, no additional gases were observed from stripping the media with helium. This result further confirms our finding that acetaldehyde and hexanaldehyde are the major gases evolved from HL60 culture.
Over the past ten years, the interest in using exhaled gases as non-invasive markers in clinical diagnostics and therapeutic monitoring has steadily increased. In parallel, considerable efforts have been taken to understand the underlying source and determinants of exhaled volatile gases. The current study demonstrates that acetaldehyde and hexanaldehyde might be useful to identify the presence of innate immune cells like neutrophils. Moreover, these gases may also have biological importance beyond their possible role as biomarkers. For example, acetaldehyde, a known lung irritant, can influence blood coagulation  and induce histamine release [50–55]. The fact that these gases might be produced endogenously by neutrophils leads to the speculation that some of the deleterious effects associated, for example, with pneumonia (characterized by aggregation of neutrophils in the lung) may be due, in part, to the production of these gases by the leukocytes themselves.
Our current study demonstrated a method to assess gases produced by immune cells under controlled conditions. This approach may prove useful in identifying gas "signatures" from other primary and transformed immune cell types.
We would like to thank Dr. Steven C. George for providing facilities. This work was supported by grants from the National Institutes of Health (R01-HL-080947 and P01-HD-048721 to D.M.C); and the Physical Sciences Dean's Innovation fund (D.R. B.).
- Baldwin IT, Halitschke R, Paschold A, von Dahl CC, Preston CA: Volatile signaling in plant-plant interactions: "talking trees" in the genomics era. Science. 2006, 311: 812-815.View ArticlePubMedGoogle Scholar
- De Moraes CM, Mescher MC, Tumlinson JH: Caterpillar-induced nocturnal plant volatiles repel conspecific females. Nature. 2001, 410: 577-580.View ArticlePubMedGoogle Scholar
- Dicke M, Agrawal AA, Bruin J: Plants talk, but are they deaf?. Trends Plant Sci. 2003, 8: 403-405.View ArticlePubMedGoogle Scholar
- Kappers IF, Aharoni A, van Herpen TW, Luckerhoff LL, Dicke M, Bouwmeester HJ: Genetic engineering of terpenoid metabolism attracts bodyguards to Arabidopsis. Science. 2005, 309: 2070-2072.View ArticlePubMedGoogle Scholar
- Ryu CM, Farag MA, Hu CH, Reddy MS, Wei HX, Pare PW, Kloepper JW: Bacterial volatiles promote growth in Arabidopsis. Proc Natl Acad Sci USA. 2003, 100: 4927-4932.PubMed CentralView ArticlePubMedGoogle Scholar
- Schnee C, Kollner TG, Held M, Turlings TC, Gershenzon J, Degenhardt J: The products of a single maize sesquiterpene synthase form a volatile defense signal that attracts natural enemies of maize herbivores. Proc Natl Acad Sci USA. 2006, 103: 1129-1134.PubMed CentralView ArticlePubMedGoogle Scholar
- Splivallo R, Novero M, Bertea CM, Bossi S, Bonfante P: Truffle volatiles inhibit growth and induce an oxidative burst in Arabidopsis thaliana. New Phytol. 2007, 175: 417-424.View ArticlePubMedGoogle Scholar
- Alving K, Weitzberg E, Lundberg JM: Increased amount of nitric oxide in exhaled air of asthmatics. Eur Respir J. 1993, 6: 1368-1370.PubMedGoogle Scholar
- Kharitonov SA, Chung KF, Evans D, O'Connor BJ, Barnes PJ: Increased exhaled nitric oxide in asthma is mainly derived from the lower respiratory tract. Am J Respir Crit Care Med. 1996, 153: 1773-1780.View ArticlePubMedGoogle Scholar
- Kharitonov SA, O'Connor BJ, Evans DJ, Barnes PJ: Allergen-induced late asthmatic reactions are associated with elevation of exhaled nitric oxide. Am J Respir Crit Care Med. 1995, 151: 1894-1899.View ArticlePubMedGoogle Scholar
- Kharitonov SA, Yates D, Robbins RA, Logan-Sinclair R, Shinebourne EA, Barnes PJ: Increased nitric oxide in exhaled air of asthmatic patients. Lancet. 1994, 343: 133-135.View ArticlePubMedGoogle Scholar
- Kharitonov SA, Yates DH, Barnes PJ: Inhaled glucocorticoids decrease nitric oxide in exhaled air of asthmatic patients. Am J Respir Crit Care Med. 1996, 153: 454-457.View ArticlePubMedGoogle Scholar
- Koizumi M, Yamazaki H, Toyokawa K, Yoshioka Y, Suzuki G, Ito M, Shinkawa K, Nishino K, Watanabe Y, Inoue T: Influence of thoracic radiotherapy on exhaled nitric oxide levels in patients with lung cancer. Jpn J Clin Oncol. 2001, 31: 142-146.View ArticlePubMedGoogle Scholar
- Liu CY, Wang CH, Chen TC, Lin HC, Yu CT, Kuo HP: Increased level of exhaled nitric oxide and up-regulation of inducible nitric oxide synthase in patients with primary lung cancer. Br J Cancer. 1998, 78: 534-541.PubMed CentralView ArticlePubMedGoogle Scholar
- Masri FA, Comhair SA, Koeck T, Xu W, Janocha A, Ghosh S, Dweik RA, Golish J, Kinter M, Stuehr DJ: Abnormalities in nitric oxide and its derivatives in lung cancer. Am J Respir Crit Care Med. 2005, 172: 597-605.PubMed CentralView ArticlePubMedGoogle Scholar
- Davies S, Spanel P, Smith D: Quantitative analysis of ammonia on the breath of patients in end-stage renal failure. Kidney Int. 1997, 52: 223-228.View ArticlePubMedGoogle Scholar
- Galassetti PR, Novak B, Nemet D, Rose-Gottron C, Cooper DM, Meinardi S, Newcomb R, Zaldivar F, Blake DR: Breath ethanol and acetone as indicators of serum glucose levels: an initial report. Diabetes Technol Ther. 2005, 7: 115-123.View ArticlePubMedGoogle Scholar
- Kamboures MA, Blake DR, Cooper DM, Newcomb RL, Barker M, Larson JK, Meinardi S, Nussbaum E, Rowland FS: Breath sulfides and pulmonary function in cystic fibrosis. Proc Natl Acad Sci USA. 2005, 102: 15762-15767.PubMed CentralView ArticlePubMedGoogle Scholar
- Novak BJ, Blake DR, Meinardi S, Rowland FS, Pontello A, Cooper DM, Galassetti PR: Exhaled methyl nitrate as a noninvasive marker of hyperglycemia in type 1 diabetes. Proc Natl Acad Sci USA. 2007, 104: 15613-15618.PubMed CentralView ArticlePubMedGoogle Scholar
- Evans TJ, Buttery LD, Carpenter A, Springall DR, Polak JM, Cohen J: Cytokine-treated human neutrophils contain inducible nitric oxide synthase that produces nitration of ingested bacteria. Proc Natl Acad Sci USA. 1996, 93: 9553-9558.PubMed CentralView ArticlePubMedGoogle Scholar
- Hersch M, Scott JA, Izbicki G, McCormack D, Cepinkas G, Ostermann M, Sibbald WJ: Differential inducible nitric oxide synthase activity in circulating neutrophils vs. mononuclears of septic shock patients. Intensive Care Med. 2005, 31: 1132-1135.View ArticlePubMedGoogle Scholar
- Shelton JL, Wang L, Cepinskas G, Sandig M, Scott JA, North ML, Inculet R, Mehta S: Inducible NO synthase (iNOS) in human neutrophils but not pulmonary microvascular endothelial cells (PMVEC) mediates septic protein leak in vitro. Microvasc Res. 2007, 74: 23-31.View ArticlePubMedGoogle Scholar
- Amann A, Smith D, (Eds.): Breath analysis for medical diagnosis and therapeutic monitoring. 2005, World Scientific, Singapore
- Deng C, Li N, Zhang X: Development of headspace solid-phase microextraction with on-fiber derivatization for determination of hexanal and heptanal in human blood. J Chromatogr B Analyt Technol Biomed Life Sci. 2004, 813: 47-52.View ArticlePubMedGoogle Scholar
- Spanel P, Smith D: Selected ion flow tube: a technique for quantitative trace gas analysis of air and breath. Med Biol Eng Comput. 1996, 34: 409-419.View ArticlePubMedGoogle Scholar
- Svensson S, Larstad M, Broo K, Olin AC: Determination of aldehydes in human breath by on-fibre derivatization, solid-phase microextraction and GC-MS. J Chromatogr B Analyt Technol Biomed Life Sci. 2007, 860: 86-91.View ArticlePubMedGoogle Scholar
- Smith D, Wang T, Sule-Suso J, Spanel P, El Haj A: Quantification of acetaldehyde released by lung cancer cells in vitro using selected ion flow tube mass spectrometry. Rapid Commun Mass Spectrom. 2003, 17: 845-850.View ArticlePubMedGoogle Scholar
- Colman JJ, Swanson AL, Meinardi S, Sive BC, Blake DR, Rowland FS: Description of the analysis of a wide range of volatile organic compounds in whole air samples collected during PEM-tropics A and B. Anal Chem. 2001, 73: 3723-3731.View ArticlePubMedGoogle Scholar
- Sive BS: Atmospheric Nonmethane Hydrocarbons: Analytical Methods and Estimated Hydroxyl Radical Concentrations. (Ph.D. Thesis.). 1998, Irvine, California: University of California, IrvineGoogle Scholar
- Miller HMMJM: Basic Gas Chromatography: Techniques in Analytical Chemistry. 1998, John Wiley & Sons, Inc. New YorkGoogle Scholar
- Smith D, Wang T, Spanel P: Kinetics and isotope patterns of ethanol and acetaldehyde emissions from yeast fermentations of glucose and glucose-6,6-d2 using selected ion flow tube mass spectrometry: a case study. Rapid Commun Mass Spectrom. 2002, 16: 69-76.View ArticlePubMedGoogle Scholar
- Wickramasinghe SN: Rates of metabolism of ethanol to acetate by human neutrophil precursors and macrophages. Alcohol Alcohol. 1985, 20: 299-303.PubMedGoogle Scholar
- Wickramasinghe SN: Role of superoxide anion radicals in ethanol metabolism by blood monocyte-derived human macrophages. J Exp Med. 1989, 169: 755-763.View ArticlePubMedGoogle Scholar
- Bond AN, Wickramasinghe SN: Investigations into the production of acetate from ethanol by human blood and bone marrow cells in vitro. Acta Haematol. 1983, 69: 303-313.View ArticlePubMedGoogle Scholar
- Wickramasinghe SN, Bond AN, Sloviter HA, Saunders JE: Metabolism of ethanol by human bone marrow cells. Acta Haematol. 1981, 66: 238-243.View ArticlePubMedGoogle Scholar
- Hazen SL, d'Avignon A, Anderson MM, Hsu FF, Heinecke JW: Human neutrophils employ the myeloperoxidase-hydrogen peroxide-chloride system to oxidize alpha-amino acids to a family of reactive aldehydes. Mechanistic studies identifying labile intermediates along the reaction pathway. J Biol Chem. 1998, 273: 4997-5005.View ArticlePubMedGoogle Scholar
- Hazen SL, Hsu FF, d'Avignon A, Heinecke JW: Human neutrophils employ myeloperoxidase to convert alpha-amino acids to a battery of reactive aldehydes: a pathway for aldehyde generation at sites of inflammation. Biochemistry. 1998, 37: 6864-6873.View ArticlePubMedGoogle Scholar
- Wagner BA, Buettner GR, Oberley LW, Darby CJ, Burns CP: Myeloperoxidase is involved in H2O2-induced apoptosis of HL-60 human leukemia cells. J Biol Chem. 2000, 275: 22461-22469.View ArticlePubMedGoogle Scholar
- Frampton MW, Pryor WA, Cueto R, Cox C, Morrow PE, Utell MJ: Ozone exposure increases aldehydes in epithelial lining fluid in human lung. Am J Respir Crit Care Med. 1999, 159: 1134-1137.View ArticlePubMedGoogle Scholar
- Corradi M, Rubinstein I, Andreoli R, Manini P, Caglieri A, Poli D, Alinovi R, Mutti A: Aldehydes in exhaled breath condensate of patients with chronic obstructive pulmonary disease. Am J Respir Crit Care Med. 2003, 167: 1380-1386.View ArticlePubMedGoogle Scholar
- Frampton MW, Pryor WA, Cueto R, Cox C, Morrow PE, Utell MJ: Aldehydes (nonanal and hexanal) in rat and human bronchoalveolar lavage fluid after ozone exposure. Am J Respir Crit Care Med. 1999, 159 (4 Pt 1): 1134-1137.View ArticlePubMedGoogle Scholar
- Postlethwait EM, Cueto R, Velsor LW, Pryor WA: O3-induced formation of bioactive lipids: estimated surface concentrations and lining layer effects. Am J Physiol. 1998, 274: L1006-1016.PubMedGoogle Scholar
- Pryor WA, Bermudez E, Cueto R, Squadrito GL: Detection of aldehydes in bronchoalveolar lavage of rats exposed to ozone. Fundam Appl Toxicol. 1996, 34: 148-156.View ArticlePubMedGoogle Scholar
- Pryor WA, Church DF: Aldehydes, hydrogen peroxide, and organic radicals as mediators of ozone toxicity. Free Radic Biol Med. 1991, 11: 41-46.View ArticlePubMedGoogle Scholar
- Pryor WA, Das B, Church DF: The ozonation of unsaturated fatty acids: aldehydes and hydrogen peroxide as products and possible mediators of ozone toxicity. Chem Res Toxicol. 1991, 4: 341-348.View ArticlePubMedGoogle Scholar
- Babior BM, Takeuchi C, Ruedi J, Gutierrez A, Wentworth P: Investigating antibody-catalyzed ozone generation by human neutrophils. Proc Natl Acad Sci USA. 2003, 100: 3031-3034.PubMed CentralView ArticlePubMedGoogle Scholar
- Mendrala AL, Langvardt PW, Nitschke KD, Quast JF, Nolan RJ: In vitro kinetics of styrene and styrene oxide metabolism in rat, mouse, and human. Arch Toxicol. 1993, 67: 18-27.View ArticlePubMedGoogle Scholar
- Norppa H, Sorsa M, Pfaffli P, Vainio H: Styrene and styrene oxide induce SCEs and are metabolised in human lymphocyte cultures. Carcinogenesis. 1980, 1: 357-361.View ArticlePubMedGoogle Scholar
- Suchocki EA, Brecher AS: The effect of acetaldehyde on human plasma factor XIII function. Dig Dis Sci. 2007, 52: 3488-3492.View ArticlePubMedGoogle Scholar
- Myou S, Fujimura M, Bando T, Saito M, Matsuda T: Aerosolized acetaldehyde, but not ethanol, induces histamine-mediated bronchoconstriction in guinea-pigs. Clin Exp Allergy. 1994, 24: 140-143.View ArticlePubMedGoogle Scholar
- Myou S, Fujimura M, Kamio Y, Bando T, Nakatsumi Y, Matsuda T: Repeated inhalation challenge with exogenous and endogenous histamine released by acetaldehyde inhalation in asthmatic patients. Am J Respir Crit Care Med. 1995, 152: 456-460.View ArticlePubMedGoogle Scholar
- Myou S, Fujimura M, Nishi K, Ohka T, Matsuda T: Aerosolized acetaldehyde induces histamine-mediated bronchoconstriction in asthmatics. Am Rev Respir Dis. 1993, 148: 940-943.View ArticlePubMedGoogle Scholar
- Kawano T, Matsuse H, Kondo Y, Machida I, Saeki S, Tomari S, Mitsuta K, Obase Y, Fukushima C, Shimoda T, Kohno S: Acetaldehyde induces histamine release from human airway mast cells to cause bronchoconstriction. Int Arch Allergy Immunol. 2004, 134: 233-239.View ArticlePubMedGoogle Scholar
- Matsuse H, Fukushima C, Shimoda T, Sadahiro A, Kohno S: Effects of acetaldehyde on human airway constriction and inflammation. Novartis Found Symp. 2007, 285: 97-106.View ArticlePubMedGoogle Scholar
- Prieto L, Gutierrez V, Cervera A, Linana J: Airway obstruction induced by inhaled acetaldehyde in asthma: repeatability relationship to adenosine 5'-monophosphate responsiveness. J Investig Allergol Clin Immunol. 2002, 12: 91-98.PubMedGoogle Scholar
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.