TLRs Regulates Reactions to Particulate Matter and Other Contaminant Considerations~!

In this article, the author explains "it is plausible that PM2.5 contains bacterial or mycoplasma lipoproteins, which are known activators of TLR2 . Because PM2.5 contain high concentrations of a large number of metals. One or more of these metals could be involved in increased TLR2- mediated cytokine production triggered by microbial lipoprotein constituents of the PM2.5. In this regard, it is interesting that TLR2 has been implicated in proinflammatory cytokine expression by airway epithelial cells stimulated with air PM containing high amounts of metals. Another possibility is that PM2.5 cytokine-inducing effects are mediated by an indirect mechanism, via the generation of endogenous “danger” host molecules activating macrophages via TLR2."

Note: Recent findings by Notch show a potentiation effect between cyanobacteria and heavy metals and thus support an important mechanism although the mechanism remains to be elicited. In addition, one must always consider alterations in methylation which can be caused by endotoxin and heavy metals. Walsh and Usman demonstrated that in autism there is alterations in the functioning of metallotheinin protein which modulates and detoxifies metals. (Treat Autism and AD/HD, Wright) In other blogs, we have explained that metallotheinin inhibits GSK-3b (Wang)which can turn off the Nrf2 antioxidant system. This could explain why there are reports that the antioxidant system is negatively effected by metals (and by endotoxin)and thus, one must also consider that in mixed environmental pollutants, there is a reduction of function of this system. In addition, there is also potential that the AhR and metals interact to influence antioxidant and detoxification. These interactions of metals and the AhR are currently being investigated through a number of projects. (Korashy) Further study may shed more light on the interactions of the Nrf2 and AhR gene batteries and how they are effected by metals from environmental exposures.

Shoenfelt, J., Mitkus, R. J., Zeisler, R., Spatz, R. O., Powell, J., Fenton, M. J., Squibb, K. A., and Medvedev, A. E. (2009). Involvement of tlr2 and tlr4 in inflammatory immune responses induced by fine and coarse ambient air particulate matter. Journal of Leukocyte Biology, 86. http://www.citeulike.org/user/HEIRS/article/7367529

Vita. Hesham Korashy, PhD. Retrieved on June 29, 2010.
http://faculty.ksu.edu.sa/hkorashy/Pages/index.aspx

Notch, E. G., Miniutti, D. M., Berry, J. P., and Mayer, G. D. (2010). Cyanobacterial lps potentiates cadmium toxicity in zebrafish (danio rerio) embryos. Environmental toxicology.
http://www.citeulike.org/user/HEIRS/article/7367622

Heavy Metals. Treat Autism and ADHD. Retrieved on June 30, 2010. http://www.treatautism.ca/?page_id=126

Wang et al. Inactivation of GSK-3 by Metallothionein PreventsDiabetes-Related Changes in Cardiac EnergyMetabolism, Inflammation, Nitrosative Damage, and Remodeling. Diabetes. June 2009. Pgs. 1391-1402.

Wright, R. O. and Baccarelli, A. (2007). Metals and neurotoxicology. The Journal of Nutrition.
http://www.citeulike.org/user/HEIRS/article/7367642