Hypoxia and Cigarette Smoke - A Combined Threat to the Brain: Role of Toll-like Receptor 4 in Neuroinflammatory Changes

  • Jayalakshmi Krishnan Assistant Professor, Department of Life Sciences, Central University of Tamil Nadu, Thiruvarur, India
  • SK Farhat Department of Life Sciences, Central University of Tamil Nadu, Thiruvarur, India.
  • Rajalakshmi Anbalagan Department of Life Sciences, Central University of Tamil Nadu, Thiruvarur, India.
Keywords: TLR4, NF-Κb, (IFN-β), Janus Associated Kinases/ Signal Transducer and Activator of Transcription (JAK/STAT), Pathogen Associated Molecular Patterns (PAMPS), Cigarette Smoke, Neuroinflammation


The mammalian brain is composed of 20% of oxygen. The depletion in the level of oxygen may lead to hypoxia, resulting in neurological changes. Recent findings of Toll-like receptors (TLR) such as TLR-2, 3, 4 and 8 in the mammalian nervous system showed neuroinflammation in the brain. The activation of TLR4 by both exogenous and endogenous ligands leads to various inflammatory diseases like atherosclerosis, Crohn’s disease, ulcerative colitis, rheumatoid arthritis and prostate cancer. This study confirms the involvement of NF-κB in TLR4-axisinduced neuroinflammationin the brain. Cigarette Smoke contains many toxic chemicals such as carcinogenic compounds which are injurious to health, causing death worldwide. The role of TLR4 in activating the Brain during Cigarette Smoke exposure is not yet understood. Hence this study reviewed the use of the cell culture in vitro model as well as in vivo mouse model of TLR4-/- mouse exposed to hypobaric hypoxia
to test hypothesis.

How to cite this article:
Krishnan J, Farhat SK, Anbalagan R. Hypoxia and Cigarette Smoke - A Combined Threat to the Brain: Role of Toll-like Receptor 4 in Neuroinflammatory Changes. J Commun Dis. 2022;54(3):67-74.

DOI: https://doi.org/10.24321/0019.5138.202291


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