Pathway Impairment that Regulates Stress Response Could Lead to A Variety of Environmental Diseases

A recent study determined that caffeine can be a preventative against some of the health effects in Parkinson's disease caused by pesticides. The following pathway is a good representation of the NO/cGMP pathway that is more than likely effected by caffeine in these conditions and can account for some of the locomoter problems in PD. As one can see, expression of other proteins including BDNF rely on its activity. In other blogs, we have noted that BDNF is altered in environmental illnesses including CFS and may account for mood changes that occur with the condition. Proper signaling of the NO/cGMP pathway is important for a number of health conditions because the pathways are consistently activated by a number of different xenobiotics and environmental cues.

Alterations in the functioning of Nrf2 and other conditions like excretory defects that increase ammonia levels with negatively impact this system. While NO is an important component of this pathway - the actual dysfunction is not related to peroxynitrite, although oxidative stress to some may increase dysfunction though loss of NO signalling. Madhusoodanan explains that in this case, "nitric oxide is a short lived free radical species synthesized by NOS. The physiological role of NO depends on its local concentration as wells as the availability of downstream targets. At low levels, activation of guanalyl cyclase is the major event by NO. The resulting elevation of cGMP serves as an regulator of many events." I suggest that many environmental diseases including CFS and MCS are probably due more to the impairments of NO/cGMP which is also negatively effected by endogenous gases including ammonia and the impairment of the system results in astrocyte damage. Because Nrf2 is also neuroprotective --- alterations in Nrf2 will contribute to neural injury. Also, cGMP inhibits the protein GSK-3b which is an off/on switch for Nrf2. Studies have demonstrated that Nrf2 regulates the antioxidant complexes of HO-1/CO which modulates CRF (which can be activated by odors) and CO activates cGMP. These pathways seem to strongly suggest that Nrf2 ultimately may influence the regulation of the stress response from environmental cues. In any case, HO-1/CO does modulate the CRF system which can be activated by response cytokines such as Il-1.

Recent studies show that increasing Nrf2 may be beneficial in limiting neural injury and in this case, I would say it probably would too. The article discusses hormetic responses that we have also discussed at length and as Mattson describes "recent findings have elucidated hormetic mechanisms of action of phytochemicals (e.g., resveratrol, curcumin, sulforaphanes and catechins) using cell culture and animal models of neurological disorders. Examples of hormesis pathways activated by phytochemicals include the transcription factor Nrf-2 which activates genes controlled by the antioxidant response element, and histone deacetylases of the sirtuin family and FOXO transcription factors." This of course may act on activities involved in methylation.



Notes:

• Diabetes exacerbates functional deficiency of NO/cGMP in ED

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