This month, a little something about antioxidants –redox for seniors and all that. You could find better info on the net, but would you bother to look it up?Anyway, save it as an ole Doc’s undocumented personal (neutral?) take as a background to evaluate antioxidant supplements. Please feel free to rebut (or rebuke) me. This is a Redox bout that affects all of us. In this corner, free radical. In the other, antioxidant.
Normally occurring antioxidants in our bodies, fat soluble vitamin E and water soluble vitamin C (ascorbic acid), can swap electrons with free radicals and help prevent disease, cell damage and cancer.
However, over the years studies of hundreds of patients do not show that vitamins C & E do a very good job of it. Adding extra vitamins C & E except for eating lots of fruits and veggies hasn’t been a champion in the fight against free radicals. You wouldn’t think that when shopping at your grocery, pharmacy or health foods store. Look at shelf after shelf of fruits, juices, veggies, processed foods, medicines and alternatives all shouting their content of antioxidant vitamins A, E & C or whatever free radical fighters are currently promoted as ready to enter the ring for us. Hopefully my corner will help you to evaluate these promotions with less bias of forethought, pro or con. I am supplement neutral for those who choose to take them or not, but if I should confuse more than I help, at least my corner is a safe and effective place to doze.
Here’s some ‘Jack-Leg’ chemistry that might horrify a biochemist. I still wince remembering the PhD chemist in a sophomore medical school class I taught. He challenged everything I said with a statement disguised as a question. But my take worked for me. Just as with much of the didactic science in my past practice of medicine and now with MPN issues, when something is ‘impossible’ for me to understand or to make happen, I just forget the impossibility and try to find a way or work around it. It’s the same with my understanding of Redox, the swapping of electrons in the reduction<–>oxidation reactions so important in the fight against free radicals. Some of you might remember getting the electron givers and electron takers confused when the Chem.101 prof. and the older textbooks were at odds with competing language. I’ll just use a prop from the Gulf oil spill for remembering electron exchange: “OIL — RIG”. Oxidation is an atom or molecule Losing electrons –Reduction is Gaining electrons. Let’s hear it for reduction! Antioxidants are reducing agents. These atoms or molecules give (RIG) electrons to free radicals thus stabilizing them.
Recall that an atomic model is made up of a central nucleus containing protons and neutrons surrounded by a cloud of electrons grouped in layers of energy shells. The number of protons determines the atom’s chemical activity, the neutrons, its isotopes. In a stable well behaved atom there are an equal number of electrons surrounding the nucleus to balance the nuclear protons. The electrons are arranged in circular levels or shells –clouds of electrons swirling around the nucleus. Their numbers and energy in successive shells are strictly defined and they stay put unless they sneak thru Gamow’s tunnel to a different energy level (a contrived explanation for their forbidden jumps to a different level). If there should be even one less or one more electron in the outer shell to make the number of cloud electrons unequal to the number of protons in the nucleus an unstable ion (free radical) ensues. This loss or gain of an electron gives the ion a positive or negative electrical charge and makes it very reactive. Quicker than a NY picosecond the now unstable atom, the free radical, will give or take an electron to or from a nearby atom or molecule (two or more atoms that share electrons).
This exchange makes the formerly unstable free radical (charged ion) into a stable (neutral) atom with equal proton –electron pairs. But now the donor/recipient atom has an unpaired set of electrons itself and thus has become a free radical. This swapping of electrons, ie. redox (reduction–oxidation) produces free radicals exponentially as the cascading sequence builds inside cells. The commotion affects DNA and causes cell damage with ensuing pathological sequelae. This is ‘oxidative stress’ and results variously in inflammation, arterial plaque, infection, mutation, cancer, premature aging and probably dandruff.
Stopping this runaway oxidative stress by donating their electrons without becoming free radicals themselves is what good antioxidants do.
In summary then, antioxidants, such as vitamins C or E, can supply a harmful free radical’s missing electron and convert (reduce) it into a harmless stable atom or molecule with a full complement of paired electrons and protons. All this without C or E becoming a free radical itself so that the chain reaction of oxidative stress is squelched. However it’s rare in science and medicine for concepts of how things work to stay the same. Evidence is now emerging that it’s their sulfur content and not the ‘Cs’ & ‘Es’ themselves which quench free radicals and protect us from oxidative stress.
It’s a complex subject not easy to simplify (read, way over my head), but to get me and thee on the same page here’s what I think I understand is happening in the antioxidant community. It seems that it might be the high sulfur content of cysteine outside our cells and glutathione on the inside that gives vitamin C & E their ability to get rid of free radicals without becoming one themselves.
To further complicate things, cysteine and glutathione, now thought to be the most important and abundant antioxidants, come in two forms, a good guy and a bad guy. One ready to serve as an antioxidant electron donor, ie. reducing agent (remember ‘RIG’). The other a no-good electron accepter, oxidant (OIL).
Bloody hell or your choice of assorted four letter vulgarities! I’m lost in this OIL-RIG stuff trying to be helpful, but ending up bordering on silly. Why did I broadcast this fight in the first place? If I got any of this correct or even if I didn’t, how come we don’t just take some cysteine or glutathione pills to relieve all our oxidative stress so to make inflammation, aging and possibly dandruff things of the past? Well turns out as they say on TV, preliminary reports are encouraging, but more study is needed.
That’s more than you need to know. Take it with a grain of salt, but not enough to raise your BP. Best,
Arch
© Dr. Arch M. and MPNforum.com, 2012. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Dr. Arch M. and MPNforum.com with appropriate and specific direction to the original content.
Comments on: "Arch’s Corner — Anti-oxidants – July 2012" (2)
L-Cysteine is an amino acid that is closely related to Cystine. Cystine contains sulfur and is formed by two molecules of L-Cysteine. L-Cysteine is also a sulfur containing amino acid. It is used to manufacture L-glutathione and L-taurine.:`:’,
Enjoy your weekend! http://www.foodsupplementdigest.com/chia-seeds-side-effects/
This “columnist” is naturally very pleased to receive your accolades from time to time, but I depend on your comments to help guide me in choosing a subject. Other columnists are so obviously on the mark that commentary is unnecessary, but my corner is sometimes on the edge re attempts to explain rather dull basic medical science in this primarily MPN oriented social-clinical forum. I would appreciate it very much if some of you would give me some guidance re what subjects you would prefer that I attempt to have a go at and in general what you consider appropriate for my column and doesn’t wander too far off topic. I hope that no one thinks this a crass try for praise ..,in this case I’ll profit best from criticism. Best, Arch