Garlic attenuates chrysotile-mediated pulmonary toxicity in rats by altering the phase I and phase II drug metabolizing enzyme system

Our plain-English summary of Garlic attenuates chrysotile-mediated pulmonary toxicity in rats by altering the phase I and phase II drug metabolizing enzyme system, by M. Ameen, M.S. Musthapa, P. Abidi, et al (Journal of Biochemical and Molecular Toxicology, 2003).

The study

• Authors: M. Ameen, M.S. Musthapa, P. Abidi, I. Ahmad, Q. Rahman
• Journal: Journal of Biochemical and Molecular Toxicology
• Published: 2003;17(6):366-71
• Cited by: 14 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Asbestos and its carcinogenic properties have been extensively documented. Asbestos exposure induces diverse cellular events associated with lung injury. Previously, we have shown that treatment with chrysotile shows significant alteration in phase I and phase II drug metabolizing enzyme system. In this study we have examined some potential mechanisms by which garlic treatment attenuates chrysotile-mediated pulmonary toxicity in rat. Female Wistar rats received an intratracheal instillation of 5 mg chrysotile (0.5 mL saline) as well as intragastric garlic treatment (1% body weight (v/w); 6 days per week). Effect of garlic treatment was evaluated after 1, 15, 30, 90, and 180 days by assaying aryl hydrocarbon hydroxylase (AHH), glutathione (GSH), glutathione S-transferase (GST), and production of thiobarbituric acid reactive substances (TBARS) in rat lung microsome. The results showed that AHH and TBARS formation were significantly reduced at day 90 and day 180 in chrysotile treated garlic cofed rats; GSH recovered 15 days later to the near normal level and GST elevated significantly after treatment of garlic as compared to chrysotile alone treated rat lung microsome. The data obtained shows that inhibition of AHH activity and induction of GST activity could be contributing factor in chrysotile-mediated pulmonary toxicity in garlic cofed rats. However, recovery of GSH and inhibition of TBARS formation by garlic and its constituent(s) showed that garlic may give protection by altering the drug metabolizing enzyme system.

Copyright 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:366-371, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10100

In plain English

This experiment used female Wistar rats at India's Industrial Toxicology Research Centre in Lucknow. The rats were split into four groups. One group got a single 5 mg dose of Indian chrysotile asbestos placed into the windpipe. A second got the same chrysotile plus a 10% (weight/volume) fresh garlic extract given into the stomach (intragastrically), dosed at 1% of body weight on a volume-to-weight basis, 6 days a week. A third got garlic alone, and a fourth got saline only, as controls. Lungs were tested 1, 15, 30, 90 and 180 days later for the enzymes AHH and GST, glutathione (GSH), and TBARS, a lipid peroxidation marker. Compared with chrysotile alone, rats given chrysotile plus garlic had lower AHH and higher GSH at days 30, 90 and 180, higher GST, and lower TBARS at days 90 and 180. However, GSH stayed significantly below controls throughout, and AHH stayed significantly above controls at days 90 and 180. The authors concluded that garlic may help attenuate fibre-mediated carcinogenic response, and called for further studies. Only lung chemistry markers were measured, not disease.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Animal experiment: rats in four treatment groups, one of them given a single intratracheal dose of chrysotile, with lungs examined at five time points after exposure
• Who was studied: Female Wistar rats from the Industrial Toxicology Research Centre breeding colony in Lucknow, India. They were divided into four groups: chrysotile alone, chrysotile plus garlic, garlic alone, and saline controls. The figures report six rats per group (n = 6). Dates are not given.
• Exposure: Chrysotile: a single intratracheal dose of 5 mg Indian chrysotile asbestos (mined at Cuddapah) in 0.5 mL saline. Garlic: a 10% (w/v) extract of fresh garlic bulbs, given intragastrically at 1% body weight (v/w), 6 days per week, throughout the experiment.
• Main results:
  • Chrysotile alone, compared with controls: AHH activity was raised at days 30 (p less than 0.05), 90 and 180 (p less than 0.001), and was significantly reduced at day 1.
  • Chrysotile plus garlic, compared with chrysotile alone: AHH activity was lower at days 30 (p less than 0.05), 90 and 180 (p less than 0.001). It was still significantly higher than in controls at days 90 and 180.
  • GSH: chrysotile alone lowered GSH compared with controls from day 15 to day 180. Chrysotile plus garlic showed significant recovery compared with chrysotile alone at days 30, 90 and 180, but GSH in that group was still significantly below controls throughout.
  • GST: chrysotile alone significantly lowered GST at all five time points compared with controls. Chrysotile plus garlic raised GST throughout compared with chrysotile alone, and GST in that group was significantly above controls at days 30, 90 and 180.
  • TBARS: compared with chrysotile alone, TBARS was lower in chrysotile plus garlic rats at day 90 (p less than 0.05) and day 180 (p less than 0.001). Both chrysotile groups still differed significantly from controls throughout the study.
  • Garlic alone, compared with controls: AHH and GST activity changed significantly, but the changes in GSH and TBARS were not significant.
• The authors' conclusion: The authors concluded that garlic's changes to lung drug-metabolizing enzymes and its reduction of lipid peroxidation suggest garlic may play a role in attenuating fibre-mediated carcinogenic response. They said this hypothesis needs further study.
• Limitations the authors state:
  • The authors stated that the mechanism by which garlic reduced TBARS formation was not yet clear.
  • The authors stated that the mechanism by which garlic attenuates chrysotile-mediated lung toxicity is not clearly known.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Chrysotile.

Medical terms in this study, explained in our Lexicon: Chrysotile, Carcinogenic, Asbestos Exposure, Glutathione (GSH).

Related studies

• Diminution in kerosene-mediated induction of drug metabolizing enzymes by asbestos in rat lungs — J.M. Arif, S.G. Khan, et al. (1992)
• Effect of coexposure to asbestos and kerosene soot on pulmonary drug-metabolizing enzyme system — J.M. Arif, S.G. Khan, et al. (1994)
• N-acetyl L-cysteine attenuates oxidant-mediated toxicity induced by chrysotile fibers — F. Afaq, P. Abidi, et al. (2000)
• Reduction of chrysotile asbestos-induced genotoxicity in human peripheral blood lymphocytes by garlic extract — K. Bhattacharya, S. Yadava, et al. (2004)
• Chrysotile-mediated imbalance in the glutathione redox system in the development of pulmonary injury — P. Abidi, F. Afaq, et al. (1999)
• Chrysotile inhibits glutathione-dependent protection against the onset of lipid peroxidation in rat lung microsomes — J.M. Arif, I. Ahmad, et al. (1996)

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