Tuesday, April 22, 2008

DOES YOUR MITO LEAK RADICALS?

Okay now, pucker up for some biology/chemistry/genetics. That means a lot of acronyms. Might want to get a 3X5 card to make a little fudge list.

First, you know about cells. I assume you know that most cells have a nucleus, which is the double-helix computer, the brains, the game-plan, the building instructions that in the aggregate create a human being out of an ovum and a sperm. The biggest single cell you’re likely to see is a hen’s egg. The sperm you’re likely to see right now is pollen. (My cottonwood is going to put out little tassels of red sexy stuff before it gets around to leaves.) Here’s the main thing you need to remember: the ovum (female) comes with the “house” and that includes the nucleus, except only half the game plan is there. That’s why an ovum is big and the sperm, which must go into “inner space” like an astronaut, is basically half-a-nucleus with a propelling tail. So teeny are they, that they are sprayed like birdshot at the ovum in hopes that one will hit and penetrate. Thus, when the two halves of double-helix nucleus wind together, the plan begins to unfold in growth.

Among the structures in the “house-ovum” is a furnace, which will make energy throughout the life of the cell. This is the mitochondria and it has its own nucleus with its own genetic instructions. Some people believe that aeons ago it was once a separate little one-celled animal that was captured by this new organization of cells constituting a creature, not so fancy as a mammal. (Hey, what about the mitochondria of, say, oysters? I googled. Oyster mitochondria is being vigorously studied!)

One’s genome, as we are used to thinking of it, is a meiotic mix of code from both parents. But the genome of one’s mitochondria comes through mitosis and is ALWAYS from the mother, the house. Powerful as the main inheritance may be, the underlying power has to come from your mother’s inherited furnace. Since my father died at 65 and my mother died at 89, I like this happenstance.

The scientists who study longevity have not settled on a consensus about what causes it, but one powerful theory focuses on the mitochondria. It seems that when a mito makes energy, it “leaks” atoms, those “free radicals” that cosmetic ads caution against. The main cell, when it is threatened by disease, produces inflammation which might be unpleasant but turns away infection. Late in life, when the mito gets leakier, the free radicals may also cause inflammation that turns against the body, causing diabetes, congestive heart failure, cancer and dementia: in short, aging.

There are certain populations, one in Japan that tends to live to a hundred and one in Nigeria that appears to be immune to Alzheimers, that either have something in their main genetic game plan that is protective or they have less leaky mitos. Birds’ mitos leak one-tenth as much as human mitos because they make and use so much energy that they’d be overwhelmed by free radicals otherwise. Fascinating, eh?

(This comes from “A unifying view on ageing and disease: the double-agent theory” authored by Nick Lane and published in the Journal of Theoretical Biology,” available through www.sciencedirect.com. It’s English so leaves “e” in “ageing.”)

Okay, now back to the oysters which are being stressed by the changes in the ocean. I just looked at the titles, so I’ll go back later but biggest worries seem to be temperature and heavy metals, esp. cadmium. Not unlike us.

In a second article at: the case is made that damage to children’s mitochondria can cause autism, by overwhelming the body’s ability to supply energy to the developing brain during a specific window of development -- and also that mild and symptom-less damage to mitos exists in some percentage of everyone (one in 4,000 is suggested), time-bombs waiting for unwarranted stress to take us out. (In the case of diabetes, for instance, the stress of over-processed foods which produce a LOT of free radicals.)

But strangely, this mito damage seems to show an “inheritance pattern” that comes through the father, affecting cousins who don’t have the same mitos. So it might have something to do with the way the larger cell-house manages its mitos. (Check out those Japanese and Nigerians. The scientists can even tell you which “alleles” -- sections of the main genome code -- have mutated in this helpful way and how one molecule can be changed to another by adding or subtracting atoms.) We’re so close! We can see the moon, but we don’t quite know how to get there yet.

BUT mild mito dysfunction “reportedly has been associated with intelligence, because it can increase activity of the brain’s NMDA receptors -- but it can also increase risk of brain disease.” (Quick, Myrtle, a definition!: Wikipedia: “The NMDA receptor (NMDAR) is an ionotropic receptor for glutamate (NMDA (N-methyl D-aspartate) is a name of its selective specific agonist). Activation of NMDA receptors results in the opening of an ion channel that is nonselective to cations. This allows flow of Na+ and small amounts of Ca2+ ions into the cell and K+ out of the cell.

“Calcium flux through NMDARs is thought to play a critical role in synaptic plasticity, a cellular mechanism for learning and memory. The NMDA receptor is distinct in that it is both ligand-gated and voltage-dependent.


Don’t we recognize “aspartate” and “glutamate” -- don’t those have something to do with sweeteners or Chinese food?

Okay. So with my NMDA receptors I’m no wiser but just as paranoid. The focus of the article is not mitos but the rising number of cases of autism in children, with special concern over the Scylla and Charybdis between the stress of vaccination versus the stress of infection. But also there is again reason to blame the modern American diet and in particular, corn, esp. processed corn oil, which is inflammatory as opposed to fish oil which is anti-inflammatory and a way of addressing free-radicals.

Should all children be tested for mito function before they are vaccinated? Should the number of vaccinations at one time be limited? We just don’t know yet.

The metaphor of house and furnace that I’ve been using leads me to reflect on the house I grew up in. At first it had a wood and coal furnace, a monster that had to be fed and klinkers removed. But the house was toasty from the bottom up and not dependent on anything but air for convection. My mother converted it to electricity for the sake of the ease and safety as she grew older. Now she didn’t have to go to the basement to chop kindling or shovel coal -- just nudge a thermostat up. That furnace became more expensive as electricity cost more. It didn’t heat the house from the bottom up the way the wood/coal had. It began to be damp. The basement was chilly. There was mold. A lesson in there somewhere -- maybe modern diets equals easy furnaces.

4 comments:

Anonymous said...

Good grief, Mary, I hope there is no pass/fail test over the material. Thanks for the clear explanation. (I hope that you can see that my tongue is firmly in cheek.) Perhaps I'll try again, in the morning, while my little brain is up for calisthenics.
Cop Car

Mary Strachan Scriver said...

You think this is hard to understand, you should see the original articles! I sat here with a legal pad and my medical dictionary and STILL had to go Google for help!

Prairie Mary

Bitterroot said...

Well, I gotta say I liked this a lot. I was a medical writer for 30 years, but I've never understood the relationship between free radicals and inflammation. So thanks for doing this research for us!

Art Durkee said...

I think there's a valid case for spreading out the vaccinations to reduce stress on the system. Rather than giving the kids full spectrum vaccinations all at once, spread them out over a couple of years, give the body time to adjust.

The link between vaccinations and autism has never been clear to me, or why the concern is so great. It's tempting to believe it's a media exaggeration that leads to cultural paranoia, like so many similar scares, although I haven't read the medical literature as yet. One wonders what the rate of actual correlation really is.