Inflammation Dr. David Agus talks about inflammation (while Sal repeatedly misspells it with one "m")
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- S: I'm here with Dr. Agus who is a professor of engineering and medicine here at USC.
- We're looking at pictures of things that seem very different to me. What is the commonality?
- Dr: The commonality is inflammation. Inflammation can be manifested by a runny nose or the flu,
- it could be manifested by an infection in your toes, it could be hitting your head playing football,
- or hitting your arm when you fall while playing a sport
- All of those can cause inflammation.
- S: Inflammation has a certain meaning in everyday language: It means something is swollen and red.
- But here we're talking about inflammation in the medical or scientific sense where it's not things are swollen and red BECAUSE of inflammation.
- Dr: Right.
- S: So what is inflammation? It isn't just swollen and redness. Football players get red and swollen.
- Dr: Inflammation occurs when your body senses danger.
- So when something is wrong--whether it be infection, whether it be trauma--in the case of football players
- your body senses danger and sends in its front-line soldiers which are its immune cells
- in order to fight whatever is causing it.
- So, if it's trauma, the immune cells go in there and they help rebuild the tissue that is damaged.
- If it's bacteria, they go in there and try to take away the bacteria so you can get over that cold or that flu.
- So, that whole process is what we call inflammation, it's the "danger process".
- S: So the immune cells go to the site of danger to either fight the danger itself or repair the aftermath of the danger.
- That sounds like a good thing!
- Dr: It's an awesome thing. The problem is your body, all of us; we care about what happens today, not down the road.
- One of the take home points that astonished me when I start to think about it,
- is that nature, evolution selects out for who has good kids, and that's what evolution is about: it's about having children; about progeny.
- It's not about what happens when we're 80yrs-old or 90yrs-old.
- And so, inflammation is fantastic at dealing with today's ramifications.
- The problem is if you get the flu today, your risk of cancer and heart disease a decade or a two decades from now are up.
- S: If I get the flu just once?
- Dr: If you get the flu once. So those five, six days where you feel horrible, your inflammation is through the roof.
- That's having ramifications down the road.
- S: This is already getting a little scary for me, because I've had the flu...so I already feel a little worried about my cancer risk.
- Dr: I can tell by looking at you!
- S: The symptoms we get when we have the flu or cold, it's not the virus that's causing it.
- The virus is causing the inflammation, which is causing the symptoms.
- Dr: Yes. That's what's wild. When you get a virus, your immune system attacks it, and then you get a fever.
- I still don't know why we get fevers. It's one of those things where cytokines,
- which are proteins the immune cells make to send out and get more reinforcements and tell the body what to do,
- it causes a fever. Is a fever good, is a fever bad? I don't know!
- We take Tylenol to lower a fever, but is that a good thing? Nobody has really looked at the long-term ramifications.
- We've looked at the short-term, but how does that effects will there be a decade from now? We just don't know.
- S: What you're saying is the reason we have inflammation is, something is happening to my body,
- I have some trauma or an injury, but I might have to run away from a lion tomorrow.
- So fix-fix-fix Sal now or fix David up so he can run away from a lion tomorrow, but in the wild I might not have lived to 40 anyway.
- So why even worry about whether that person might get cancer if they get to 40 or 50? Once they're past the point of reproduction.
- Dr: Right, the body has to choose priorities. The priority is today rather than tomorrow.
- An amazing study was done where we gave patients what we call a "statin".
- Statins are drugs that were developed to block the synthesis of cholesterol.
- We thought, you know, people with higher cholesterol--particularly the bad one, LDL--those people have a higher incidence of heart disease.
- So, if we block the synthesis, we're going to affect heart disease.
- What do you know? We did! A dramatic effect: We lowered the death from heart disease with these drugs.
- S: so it seems like they worked!
- Dr: Right. Then a company, or a very clever group did a trial where they gave people with normal cholesterol these drugs.
- It also had a dramatic effect, in that it delayed heart attack and stroke by almost a dozen years,
- and it reduced the incidence of cancer by about 40%.
- S: So cancer, something we don't normally associate with cholesterol.
- Dr: So it turns out these drugs, which are the biggest drugs in terms of sells we ever had,
- worked by lowering inflammation.
- So the affected heart disease wasn't by lowering cholesterol, it was predominantly by lowering inflammation.
- And the affect on cancer was by lowering inflammation.
- In fact, remember when the swine flu came out a couple of years ago?
- If you got the swine flu, the only thing that protected you from your lungs collapsing going on what we call
- a ventilator, a breathing machine, was being on one of these statins.
- S: Because it would stop the inflammation. Because with swine flu, people were dying from inflammation going nuts.
- Dr: Yes.
- S: Fascinating. The people who are dying of heart disease, is it the cholesterol that's killing them or the inflammation?
- Dr: I think it's a chicken-and-the-egg phenomenon where the inflammation allows the cholesterol to deposit; and they go together.
- S: It's really the statins affect inflammation, which then reduces cancer by stopping the inflammation.
- Dr: Exactly. One of the problems we have in Biology and Medicine is what you can measure.
- So, I can measure cholesterol. I don't really know how to measure inflammation well.
- So while we can make these associations in big studies where we look back,
- if I had a metric, a blood test or something to look at for inflammation, I could optimize this.
- S: Can you not just measure the amount of cytokines or other inflammatory types of things?
- Dr: There are different types of inflammation. So, some inflammation can be good, some can be bad.
- Some can be really causal, some can be a little causal.
- So we're putting them all into one basket now, which is inflammation, the key is to start to tease them out,
- and be able to modulate them.
- You can develop a drug, but then you would have to optimize it for a particular purpose.
- So, these were optimized to lower cholesterol. They do that very well.
- It also lowers inflammation, and they work beautifully in that regard.
- But how do we optimize that going forward?
- It also means that when you look at your lifestyle and my lifestyle, we have to limit inflammation.
- So, what are the easy ways to do that?
- One is, which I think should be mandatory, is things like the flu shot.
- So again, the flu shot will certainly delay you from having or prevent you from having a bad flu...
- S: Which is good today and good tomorrow.
- Dr: Yes, it lowers heart disease and cancer down the road.
- S: I had no clue. I thought the flu shot was just a nice thing to avoid a week of the sneezing.
- But flu shot can actually reduce your cancer...
- Dr: ...and heart disease down the road. And we have to think long-term as a society.
- S: What about statins? I mean, it seems things like Lipitor, etc.--
- no one should take medical advice based on a thing in a video--
- but, are taking it, just for heart disease? Or are people taking it more broadly now?
- Dr: Listen: I'm a believer that these drugs have such a profound affect on cancer, heart disease, stroke,
- potentially Alzheimer's, that you should consider taking it to prevent these diseases.
- And again, giving no recommendations, but what I say is, you and parents should talk to your doctor and say,
- "Why shouldn't I be on this drug? "
- S: And there are some side effects? Are they easy to test for?
- Dr: They test for them, and they're reversible.
- You have to do a risk-benefit analysis. Have to look at you and say, are you at high risk for XYZ?
- If you are, what can prevent it or delay it?
- The name of the game is not treating disease, it's preventing disease.
- S: This is fascinating. But no advice here, everyone should talk to their doctor.
- Dr: Btw, another great medicine that reduces inflammation is aspirin.
- S: Aspirin, I've heard of that!
- Dr: It's a helluva drug! Again, there are side effects to aspirin, it can effect bleeding,
- but at the same time, it gives dramatic effect by lowering inflammation.
- S: Right. And that is the main side effect, it's an age-old drug, and it's a blood thinner,
- if you get a cut or you bleed while taking aspirin, you might bleed more.
- Dr: Right. Blood thinner is a funny word, I'm not sure what it means.
- I keep thinking paint thinner when you say that.
- S: That's how I imagine it.
- Dr: It binds to the platelets and blocks them from activating, it stops them from working very well.
- S: It's more anti-clotting?
- Dr: Right. And platelets are one of the key components in clotting, and they certainly affect it.
- S: So your blood will have the same viscosity, it just won't clot as easily.
- Dr: Exactly. And you could certainly paint a wall with either one.
- S: That's a little morbid. Thanks so much
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