Antioxidants and cns

[Rick Murchison]

Lots of good stuff here... lots of ... interesting ... stuff.
I am satisfied that antioxidants in general won't hurt me, especially those I get from natural foods like grape juice and oranges.
I am also satisfied that if antioxidants have any reduction effect on my susceptability to oxygen toxicity those effects are so minimal as to be nearly immeasurable, and certainly not of a magnitude that would warrant any relaxation of my oxygen exposure limits basis.
In other words, with reference to the original question - "what is your suggestion on antioxidents(sic) for lowering the chances of a cns hit?" - my suggestion is that there may be good reasons to take antioxidants, but lowering the chances of a CNS hit ain't one of 'em.
Rick

 

[wk2000]

I have been lurking here for several months in anticiption of resuming a diving habit abandoned after marriage, kids, etc. In the 90's I conducted research into antioxidants being used as organ preservation additives for transplants. We were using experimental compunds called lazariods, which were extremely potent lipid peroxidation inhibitors. The drug company was using them to improve outcomes in head trauma. (NOTE to PETA activists: don't read this part)- The model the drug company used was a closed head injury inflicted on monkeys. Pretreating the monkey with a lazaroid resulted in a significantly higher survival rate, and lower long term disability, and the drug was in Phase II clinical trials with humans when I moved on- not sure where it is now. The interesting thing is, one of the control agents used was Vit E. According to the guys at the company, Vit E was so effective that they COULD NOT inflict a fatal closed head injury on the monkey without massive mechanical tissue disruption- it worked even better than their new drug! According to him, all the guys in the lab started taking Vit E after they saw this! I understand that dcs is a different process, but lipid peroxidation is one of the final common pathways for all cns injuries. Anyway, it makes me wonder if taking Vit E might be of some benefit even in preventing microbubble issues.

 

[Dr Deco]

Hello wk 2000:

Both vitamins E and C have been shown to have some effect in the mitigation of oxygen seizures in animals. Some physicians recommend them to their patients undergoing hyperbaric oxygen therapy in a chamber. No one has ever really assessed the therapeutic effect, to my knowledge, in humans. I doubt, again, that it would be something to stake your life on in diving.

In the case of microbubble-generation issues (your last sentence), I am losing your connection to brain trauma. It is true that nuclei formation has been mentioned as a possible consequence of brain traumatic injury, but I have not heard of vitamin E as a protective agent in this case of an agent to reduce bubbles in diving.

Dr Deco :doctor:

 

[wk2000]

No, I wasn't very clear- I don't think Vit E might help prevent microbubbles-

I was wondering if Vitamin E might reduce lesions noted on brain MRI of long-term divers which some speculate are the result of microbubble injury.


Not a bit of evidence to support that concept, but OTOH Vit E is pretty cheap and pretty safe...

 

[fins wake]

I am also satisfied that if antioxidants have any reduction effect on my susceptability to oxygen toxicity those effects are so minimal as to be nearly immeasurable, and certainly not of a magnitude that would warrant any relaxation of my oxygen exposure limits basis.

This is a very good remark and IMHO the only possible answer to the original question. Limit your oxygen exposure, as the good doctor also wrote.

 

[MB]

I did a search on The National Library of Medicine's PubMed for "PIU's" (and pyrogallol inhibition unit) before I asked you about it and found no papers listed that used PIU as a unit of measurement. Not one. Zero. Nada... I'm still willing to learn, though. QUOTE]

Uh, Bill. I think I discovered the problem with your search. I think you mis-spelled PIU. I think you really want "peeee-u".

As for sales, there's some stuff sold locally to the ladies of Boca Raton that is said to be very effective as a wrinkle cream. I'm guessing (but obviously not making medical claims, and no such advice should be inferred in this post) that you could get a comparable effect with only 120 jars of it, instead of the 140 jars you mentioned previously.

 

[BillP]

SOD activity is determined by measuring the inhibition of the autoxidation of pyrogallol by superoxide radicals (or anionic peroxide radicals). I believe that one unit (PIU) of SOD activity is defined as the amount of enzyme that inhibits the reaction by 50%. You can check on that one for me.
Pesky

Hey Pesky, checked that one for you as you asked, and actually found something! The "pyrogallol autoxidation method" is a method of estimating SOD activity, and I found one (unpublished?) paper out of India that used the definition of "unit" of SOD activity that you have above. See:

http://www.dli.gov.in/data0/001/657/TXT/00000052.txt

Before you get too excited, while it appears that Roger didn't make up the the use of "units" of pyrogallol inhibition, it still seems that it's nowhere near the "common term used by medical researchers" that you made it out to be. The "pyrogallol autoxidation method" may be one method of investigating SOD activity, but in my searching the more common "International Units" (IU) is typically used by medical researchers to measure SOD doses. Dunno how a "PIU" compares to the standard "IU", but that remains a side issue and you still have some homework to do.

So just how much SOD is "well absorbed" systemically from a cream or nasal spray as you claim, how much of it crosses the blood-brain barrier, does it cross in sufficient amounts to affect the chances of O2 toxicity seizures in divers, and while you're at it, what's the dose of the cream or nasal spray that would be effective? Since you're an expert on antioxidants and you recommend SOD cream/spray's use to help prevent CNS O2 toxicity, you should know all this.

 

[BigJetDriver]

Folks,

In regard to PIU's and Mess'rs. Marklund and Marklund, I did a wide-ranging search for both "pyrogallol inhibition units" and the article in the European Journal of Biochemistry by Marklund, S. and Marklund G. (1974 Vol 47 P 469-474).

(1) I was not able to pull up the actual article. If someone can post a link to that in an active format, I would appreciate it.

(2) I found many references to "PIU's", and to the "Marklund Method". Inevitably, however, they all seem to be in "fringe" publications, and "alternative asian medicine" references.

Example:

Brains (rat) were homogenized in nine volumes of ice-cold buffer (0.32 mol/L sucrose, 1 mmol/L EDTA and 10 nmol/L Tris-HCl, pH 7.4) followed by centrifugation at 13,600 x g for 30 min at 4 [degrees] C. The supernatant was used for the assays of SOD and GSH-Px. SOD was assayed by the pyrogallol method of Marklund and Marklund (1975). One unit (U) of this enzyme activity is defined as the amount of enzyme causing a 50% inhibition of pyrogallol autoxidation at 37 [degrees] C. Activity is expressed as U per mg of protein (U/mg protein). GSH-Px was assayed by the method of Hafeman et al. (1974). One unit (U) of GSH-Px activity is defined as a decrease in the log[GSH] of 0.001 per minute after the decrease in the log[GSH] per minute of the nonenzymatic reaction is subtracted. Activity is expressed as U per mg of protein (U/mg protein). Protein was measured by the method of Lowry et al. (1974) using bovine serum albumin as the standard.
Effect of CDA-II, Urinary Preparation, on Lipofuscin, Lipid Peroxidation and Antioxidant Systems in Young and Middle-Aged Rat Brain.
American Journal of Chinese Medicine, Wntr, 2001, by Wen-Chuan Lin, Yueh-Wern Wu, Tung-Yuan Lai, Ming-Cheng Liau

(3) I have seen absolutely NO, repeat NO, references to any studies done under scientific conditions that suggest that ANY of this would be of value in mitigating the effects of DCS/DCI in any of its forms!

(4) While the academic and medical training and histories of Doc Vikingo, Doc Deco, and others who post here are known, Pescador 775 does not seem to have any medical training that he is willing to list.

IN SHORT: My personal recommendation here would be the application of liberal amounts of Morton's Large Crystal Rock Salt!

BJD :doctor:

P.S.---I sign off in this manner here, instead of my usual "flying helmet" because I do, in fact, have some medical standing in this matter.

I am a certified Diver Medic Technician, trained at the University of Texas Medical Branch, Galveston, Texas. My instructors were, among others, Dr. Richard Mader, a noted hyperbaric medicine researcher, and Kevan Corson, an ex-Navy Seal medic and well-known DMT and CHT educator.

 

[BigJetDriver]

Further to the above:

I personally take a propylactic dose of aspirin daily, but this is based on extensive studies of its relative value in preventing heart attacks over the long term. It has nothing to do with the deco diving that I do.

Cheers! BJD

 

[miguel sanz]

Further to the above:

I personally take a propylactic dose of aspirin daily, but this is based on extensive studies of its relative value in preventing heart attacks over the long term. It has nothing to do with the deco diving that I do.

Cheers! BJD

excuse me, I hope you don´t mind I ask this but why do you take prophylactic aspirin and what dose?