Neutrophil mediated inflammatory lung damage following single Sub lethal inhalation exposure to plant protein toxin abrin in mice

Abstract

Abrin, a highly toxic plant protein found in the seeds of Abrus precatorius plant. To date, there is no antidote against abrin intoxication. Abrin is toxic by all routes of exposure, but inhalation exposure is the most toxic of all routes. Present study was conducted to evaluate the acute inhalation toxicity of aerosolized abrin in BALB/c mice. Animals were exposed to 0.2 and 0.8LC50 doses of aerosolized abrin and evaluated at 1 and 3 day post toxin exposure. Bronchoalveolar fluid from lungs was used for evaluation of markers for lung injury. Abrin inhalation exposure caused rise in LDH activity, protein content, increase in β-glucuronidase and myeloperoxidase activity. Increase in CRP activity, MMP-9 expression and recruitment of CD11b + inflammatory cells in lungs was also observed which was associated with severe inflammation and lung damage. Histopathological findings support the lung damage after abrin exposure. Our results indicate lung injury after single aerosol inhalation exposure, associated with excessive inflammation, oxidative stress, pulmonary edema followed by lung damage. These results could supplement treatment strategies and planning for therapeutic approaches against aerosolized abrin inhalation exposure.

Keywords:

• Abrin
• inflammation
• inhalation
• lung damage

Acknowledgments

We thank Dr DK Dubey, Director, Defense Research and Development Establishment for providing all facilities and Dr Rahul Bhattacharya, Head, Pharmacology and Toxicology Division for constant support and guidance. We also thank Dr SC Pant for help in histopathology interpretations. Ms Bhavana is recipient of UGC Senior research fellowship. This work was supported by the grant from Ministry of Defense, India. This article is assigned DRDE accession number HR-2018-28.

Declaration of interest

The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.