Free Radicals, pt. 1
Free radicals have become the major fad of this young decade. Everywhere you go there’s some sort of marketing designed to target people’s innate fear of the unknown. WATCH OUT FOR FREE RADICALS, THEY’LL KILL YOU. HOW ABOUT A NICE GLASS OF ANTIOXIDANTS? (That last one was some poor guy working at Teavana trying to get me to try a small cup of mediocre and overpriced tea). But the fact of the matter is the general public is largely uneducated as to what free radicals and antioxidants are. I bet if I went up to Teavana guy and asked him how his antioxidants work he’d be clueless. Just doing a quick search on the topic and you can see just how mysterious the topic is for people. Diets against free radicals, special vitamin supplements, even special shower heads that “oxygenize” water to reduce free radical damage to your skin (for $40-$60). Some health gurus advocate taking cold showers because in whatever bizarre universe they live in this increases free radical resistance and increases blood flow around your body to help “wash away toxins” (which is false, your body restricts blood flow to the skin in cold environments to maintain optimal warmth to your organs, automatically robbing the gurus of any credibility they had to begin with).
So what are free radicals? A simple definition is an unstable chemical compound with a single unpaired electron in their outer orbital. So what if it has an unpaired electron, what can that possibly do? IT CAN $%&# YOUR CELLS UP.
Free radicals come in different varieties and are made in different ways. For the most part, free radicals are nasty buggers and do a lot of harm. In some instances your body generates them for protection (like destroying invading bacteria).
One way they’re made is by ionizing radiation, this produces the hydroxyl FR’s, the most destructive type. If the mitochondria in your cells become damaged they can produce superoxide FR’s. Even just high concentrations of oxygen is dangerous because it can produce both hydroxyl AND superoxide FR’s in addition to hydrogen peroxide, which is very toxic to your cells. As I briefly mentioned above, the neutrophils and monocytes that are a part of your immune system generate free radicals to make bleach, which then destroys invading bacteria. Medications like acetaminophen/paracetamol (Tylenol) are converted to FR’s in your liver, which is why an overdose of Tylenol can punch too many holes in a person’s liver and kill them. Cigarette smoke produces quinone/hydroquinone FR’s from the tar, and also produces nitric oxide gas, another FR. Pollution, metals (iron, copper), gases, the sources are endless.
How do these free radicals cause damage? Well as the definition highlighted they’re unstable, so they attack other molecules to steal an electron and pass that instability off to whatever it attacked. It’s an endless chain reaction that ends up destroying the cell membrane and primarily the nucleic acids making up the cell’s DNA. The DNA clumps up and dissolves while the membranes become unstable and allow a massive influx of Calcium into the cell (long story short, lots of calcium in the cell triggers the cell to commit suicide). All of this damage accumulates over our lifetimes and can add up.
(Part 2 will cover how the body neutralizes free radicals and go into the specifics of free radical injuries).
Free Radicals pt. 2
In part 1 we went over what free radicals are and what they do so we can better educate people against fad scams and the like. I briefly showed you how free radicals destroy cells, so how do we neutralize them?
There are 3 main mechanisms by which your body naturally gets rid of free radicals, a sort of inherent antioxidant defense. The first is Superoxide dismutase, which converts superoxide free radicals (like those emitted from damaged mitochondria) into peroxide and oxygen. Glutathione peroxidase is the main component of the liver that gets rid of free radicals, and is active in the pentose phosphate pathway involved in glycolysis. When someone overdoses on Tylenol is uses up all of the Glutathione peroxidase and the free radicals run amok. The last mechanism you might be a little more familiar with: catalase. It converts peroxide into oxygen and water.
The extrinsic mechanism of defusing free radicals involves vitamins, and this is where the people making a gold mine off of peoples ignorance get the fodder for their cash machines. The mechanism by which an antioxidant works is that it donates an electron to the free radical and remains stable, stopping the chain reaction of chemical instability. There are two vitamins in our diet that do this very well. You don’t have to do anything other than maintain a healthy balanced diet to obtain them, you don’t have to buy supplements through a special company. In fact you probably get enough of them without even realizing it: Vitamin E and Vitamin C. Vitamin E protects the lipids in the cell membranes from getting attacked, ensuring membrane integrity and preventing a flood of calcium. Vitamin C neutralizes free radicals produced by pollution and cigarette smoke (FOR THE LOVE OF NUTELLA, IF YOU SMOKE AT LEAST GET LOTS OF VITAMIN C. Smokers are always slightly deficient in Vitamin C because they use it all up neutralizing the hydroxyl free radicals). If you’re really hardcore you can always ingest a lot of Selenium, which neutralizes free radicals in the cytosol of your cells.
So with all of the free radical ignorance floating around out there, let’s look at a few cases of real free radical injury. You know, the stuff that’s not going to be fixed with a cup of tea and some vitamin supplements.
“Tylenol: come for the pain relief, stay for the fulminant hepatic failure.” As mentioned previously, the acetaminophen in Tylenol creates free radicals in your liver. To compensate for this, the Glutathione peroxidase in your liver neutralizes the free radicals, but there’s only so much Glutathione peroxidase to go around. If you drink a bunch of booze you’ll have even less to address any free radical crisis. The damage causes necrosis of your hepatocytes, typically around the central veins in your lobules. This affects your body in so many ways because you kind of need a functioning liver to, ya know, live. But in people with severe free radical damage it has been particularly noted that they can’t make clotting proteins as well, especially Factor VII. When it comes to Tylenol overdoses the treatment is N-acetylcysteine. This allows the cells to efficiently recycle Glutathione peroxidase and better mop up the damage.
“As if the heart attack wasn’t bad enough…” Myocardial ischemia occurs when the blood flow is cut off to tissue due to an infarct. When blood flow is restored to the dead tissue BAM there’s a bunch of oxygen in the graveyard of cells and it turns into superoxide free radicals (remember, the damaged mitochondria) and it causes further damage to the tissue.
“Congrats on the new baby! By the way I think I made them blind.” Premature babies aren’t ready to be outside of the womb in that their lungs aren’t properly lubricated to accommodate that expansion/contraction movement your lungs do all day, everyday. As a result, they kind of collapse in on themselves and the result is Respiratory Distress Syndrome. Obviously if you want them to live you put them on oxygen, but as we discussed oxygen in high quantities makes free radicals. This damages the retina and can permanently blind the infant.
“It’s like that one episode of House with the porn star!” Too much iron in the body is the result of a disease called Hemochromatosis. That iron gets a boost of energy from sunlight (or some other source) and gets converted into a free radical, like in that episode of House when they put the guy in the tanning booth.
“It’s like that other episode of House with the copper rings in her eyes!” Wilson’s disease, aside from being a coveted piece of medical trivia is the accumulation of copper in the body. It accumulates in specific places like the eyes and brain, but also the liver. Putting two and two together, you can see how a bunch of copper hanging around in a location where free radicals are normally being generated can… exacerbate the situation significantly.
Well there you have it, we went over what a free radical is, what it does to cells, how the neutralize them and what some specific examples of actual free radical damage is like.
Stay tuned for some closing thoughts on free radicals, antioxidants, and the massive amounts of ignorance that allows people to make a fortune off of consumers.