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| Read the text and place the signs on the arrows |
Watson's contributions are mainly contrarian. In this hypotheses about the link between major chronic diseases and redox potential he described the metabolic pathways and cellular structures by which the lack of oxidation may contribute to these diseases.
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| http://www.nature.com/nrc/journal/v3/n10/full/nrc1189.html |
"There were important clues, he speculated, in the chemistry of oxidation and reduction reactions. The body's cells cannot survive without making both oxidants and antioxidants. "There is a delicate balance" between the two, Watson observes. Physical exercise prompts the body to make large numbers of oxidants – molecules called reactive oxygen species, or ROS. In a cellular organ called the endoplasmic reticulum (ER), one such "species," the oxidant hydrogen peroxide (H2O2), helps forge chemical bonds (disulfide bonds) which stabilize proteins as they fold.
When there is not enough oxidation in the ER, Watson says, proteins emerge unfolded, and cannot function. This, he proposes, causes the inflammation that harms the pancreas, sometimes causing type 2 diabetes. Hence, Watson suggests, exercise, which promotes oxidation, plausibly can have a beneficial effect on those with high blood sugar. Such benefit would be lessened if not abolished, he speculates, if such an individual consumed large quantities of antioxidants – just as athletes who take large quantities of antioxidant supplements do not seem to benefit or benefit less from their exertions.
Watson has two take-home messages for his audience. "The first is that we sorely need to take a much more serious and thorough scientific look at the mechanisms through which exercise improves our health." Watson is planning a scientific meeting at Cold Spring Harbor Laboratory later this year which he hopes will launch a larger scientific effort.
There is a second message. "I am not a physician and I cannot offer advice about how people should treat their diabetes; I am advancing a novel idea about how type 2 diabetes can occur. But I also note that just about every doctor I've ever known tells every patient who is capable of doing so to exercise. I think exercise helps us produce healthy, functional proteins. But we really need to have some high quality research to demonstrate this.""
BTW there is also phytochemicals to fight or delay cancer
Nat Rev Cancer. 2003 Oct;3(10):768-80.
Cancer chemoprevention with dietary phytochemicals.
Author information
- College of Pharmacy, Seoul National University, Shinlim-dong, Kwanak-ku, Seoul 151-742, South Korea. surh@plaza.snu.ac.kr
Abstract
Chemoprevention refers to the use of agents to inhibit, reverse or retard tumorigenesis. Numerous phytochemicals derived from edible plants have been reported to interfere with a specific stage of the carcinogenic process. Many mechanisms have been shown to account for the anticarcinogenic actions of dietary constituents, but attention has recently been focused on intracellular-signalling cascades as common molecular targets for various chemopreventive phytochemicals.
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