The effect of m-xylene on rat lung benzo[a]pyrene metabolism and microsomal membrane lipids: comparison with p-xylene

Stickney, J. A.; Roberts, Alan E.; Silverman, Diane M.; Schatz, Robert A.

doi:10.1016/0300-483x(89)90005-x

Cited by 17 publications

(14 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Levels following ip injection were 0.65, 0.62, and 2.6 µmol/g for blood, lung, and liver, respectively (Stickney et al, 1989). The blood levels observed in this study are higher than those observed by others (Elovaara et al, 1987;Kaneko et al, 1995), but the methods in each of the studies differed, which could account for this variation.…”

Section: Discussionmentioning

confidence: 47%

LOW-LEVEL m-XYLENE INHALATION ALTERS PULMONARY AND HEPATIC CYTOCHROME P-450 ACTIVITY IN THE RAT

Foy¹

1996

Journal of Toxicology and Environmental Health

View full text Add to dashboard Cite

m-Xylene is a commonly used industrial solvent that has been shown to alter mixed-function oxidase (MFO) activity, in an organ- and isozyme-specific pattern, following intraperitoneal administration of the solvent. The purpose of this work was to determine whether similar alterations occurred in cytochromes P-450 (CYP) following m-xylene inhalation, the primary route of occupational exposure. A single 6-h exposure to m-xylene resulted in the inhibition of aryl hydrocarbon hydroxylase (AHH) activity in the lung while the activity of AHH was unchanged in the liver. CYP 2B1 activity, which is responsible for the metabolism of benzo[a]pyrene (BaP) to relatively nontoxic metabolites, was decreased in lung but not in liver. The activity of CYP 1A1, responsible for the metabolism of BaP to reactive/toxic products, was not altered in lung or liver. The CYP 2B1/1A1 ratio is an indirect indicator of the pattern of BaP toxication/detoxication. This ratio was decreased in lung, suggesting that BaP metabolism is shifted toward toxication. CYP 1A2 and CYP 4B1 activity was decreased in the lung while remaining unchanged in the liver. CYP 2E1 activity was also inhibited in lung while its activity was increased in the liver. This organ-specific inhibition of pulmonary cytochromes P-450 may be due to the lower MFO activity in the lung compared to liver. Alteration of the cytochromes P450 by m-xylene could result in a change in the metabolic profiles of xenobiotics in coexposure or subsequent exposure scenarios in increased or decreased toxicity in an organ-specific fashion.

show abstract

Section: Discussionmentioning

confidence: 47%

LOW-LEVEL m-XYLENE INHALATION ALTERS PULMONARY AND HEPATIC CYTOCHROME P-450 ACTIVITY IN THE RAT

Foy¹

1996

Journal of Toxicology and Environmental Health

View full text Add to dashboard Cite

show abstract

“…Many agents can affect membrane fluidity by changing the proportion of unsaturated acids in the membrane (Heipieper and de Bont, 1994), binding to phospholipid polar head or the acyl chain (Balasubramanian et al, 1997;Chen et al, 1998), changing phospholipid/cholesterol ratio (Bjorkman and Jessop, 1994;Courjault-Gautier et al, 1995;Lee et al, 1999;Stickney et al, 1989), disrupting the cortical lattice (Remy-Kristensen et al, 2000), inducing lipid peroxidation, or generating NO (Bruch and Thayer, 1983;Choi and Yu, 1995;Imai et al, 2000;Karbownik et al, 2000;Mecocci et al, 1997;Muriel and Sandoval, 2000;Ohyashiki et al, 1986;Stickney et al, 1989;Tsuda et al, 2000;Wu et al, 1993). Besides stiffness change, noise-induced reduction in the OHC membrane fluidity can also result from generation of reactive oxygen species (ROS).…”

Section: Mechanism Of Noise-induced Reduction Of Ohc Plasma Membrane mentioning

confidence: 99%

Effects of intense noise exposure on the outer hair cell plasma membrane fluidity

Chen

Zhao

2007

Hearing Research

View full text Add to dashboard Cite

“…Toluene has been shown to induce lipoperoxidation in pulmonary alveolar macrophages [20], while p-xylene, a structural analogue, caused similar increases in lung microsomes [21]. Given these findings, this study was undertaken to determine whether reactive oxygen species and related membrane events play a role in the neurotoxicity that results from toluene exposure.…”

mentioning

confidence: 99%

Effects of toluene and its metabolites on cerebral reactive oxygen species generation

Mattia

LeBel

Bondy

1991

Biochemical Pharmacology

View full text Add to dashboard Cite

Abstract-The effects of toluene on lipid peroxidation and rates of reactive oxygen species (ROS) formation have been studied in isolated systems and in vivo. The induction of reactive oxygen species was assayed using the probe 2' ,7'-dichlorofluorescin diacetate (DCFH-DA). Toluene exposure (1 g/kg, 1 hr, i.p.) did not stimulate cortical lipid peroxidation as evaluated by measurement of conjugated dienes. Exposure to toluene, however, both in vivo and in vitro, caused a significant elevation of ROS formation within cortical crude synaptosomal fractions (P2) and microsomal fractions (P3). The ROSinducing properties of toluene were blocked in vivo in the presence of a mixed-function oxidase inhibitor, metyrapone. This suggested that a metabolite of toluene may catalyze reactive oxygen formation. Both benzyl alcohol and benzoic acid, in vitro, were found to have free radical quenching properties, while benzaldehyde exhibited significant induction of ROS generation. It appears that benzaldehyde is the metabolite responsible for the effect of toluene in accelerating reactive oxygen production within the nervous system. Benzaldehyde may also contribute to the overall neurotoxicity of toluene.

show abstract

The effect of m-xylene on rat lung benzo[a]pyrene metabolism and microsomal membrane lipids: comparison with p-xylene

Cited by 17 publications

References 32 publications

LOW-LEVEL m-XYLENE INHALATION ALTERS PULMONARY AND HEPATIC CYTOCHROME P-450 ACTIVITY IN THE RAT

LOW-LEVEL m-XYLENE INHALATION ALTERS PULMONARY AND HEPATIC CYTOCHROME P-450 ACTIVITY IN THE RAT

Effects of intense noise exposure on the outer hair cell plasma membrane fluidity

Effects of toluene and its metabolites on cerebral reactive oxygen species generation

Contact Info

Product

Resources

About