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Course: Health and medicine > Unit 14
Lesson 5: Inflammation and exposuresInflammation
Dr. David Agus talks about inflammation (while Sal repeatedly misspells it with one "m"). Created by Sal Khan.
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- It says in my Anatomy and Physiology text book (and I've heard from my professors) that fever is beneficial in that the high temperatures may inhibit some pathogens. Also that every degree Celsius your body temp rises, metabolic rate rises by 10% because cells and enzyme reactions become quicker. This could result in a a faster repair process.
Is this information about fevers relatively new, or is it not widely accepted?(18 votes)- No, this is not new information. My old nursing text agrees with your A&P. I think the point he was making is that we don't fully understand the affect of fever on the body. As you pointed out, as temp rises metabolic rate also increases. Every cell in your body experiences that increase, including cancer cells. Because of this, although fever may have a great short term outcome, it may actually have a detrimental long-term effect.(8 votes)
- What is your view on Eastern medicine/homeopathic remedies to reduce inflammation naturally as prevention for long term illnesses? Do you believe one's diet causes the same type of inflammation for the diseases you mentioned like cancer, for example?(3 votes)
- So, the process of inflammation is a natural body response, but it can be over-dramatized by one's diet,
causing problems.(1 vote)
- This video did not discuss the topic of 'Inflammation' as I hoped. It mentioned Inflammation and seemed more like a 'drug rep' trying to sell a doctor on 'statin' medication.(3 votes)
- If there isn't a good test for inflammation, what is my rheumatologist testing when they say my inflammation levels are high?(2 votes)
- There are a couple of tests for inflammation that are nonspecific. These may have been performed for multiple reasons. An ESR measures for inflammation by assessing the rate of which RBCs settle in a test tube. The more fibrin that accumulates due to an inflammatory process, the higher the rate. An ANA will measure for antibodies that are produced in reaction to either a pathogen or an autoimmune disorder. Finally a C-reactive protein will be elevated in a multitude of inflammatory responses (bacterial, viral, fungal, autoimmune). As Dr. Agus stated in the video, there is no sure way to test for "bad" inflammation because there are so many types. All these tests are nonspecific and just test for inflammation.(2 votes)
- My understanding is that inflammation is a process that helps decrease infection. To speed up this process, the body temperature also goes up (which we called fever). So, shouldn't we be more focused on treating the infection than the inflammation? Please correct me, if I'm wrong.(2 votes)
- You are correct.
If inflammation is caused by infection, the infection can be treated (antivirals, if caused by virus; antibiotics, if caused by bacteria); however, we have our own innate immune response, as well as our adaptive immune response, therefore often we don't need to seek treatment; rest and lots of fluids should aid in our body resolve the infection on its own.
However, inflammation does not always equate infection. You can have inflammation without infections, such as is the cause with injuries. If you cut yourself, for example, you may feel pain, heat, swelling and see redness - these are all signs of inflammation and part of the innate immune response.
Injury, whether outside of the body or inside the body, and infection will trigger the same innate immune response, and therefore demonstrate signs and symptoms of inflammation.(2 votes)
- If statins reduce inflammation, is it possible that they can reduce episodes in major depressive disorder (MDD)? I ask because some people believe there is a connection between MDD and inflammation of the central nervous system.(2 votes)
- At4:33Dr. Argus mentions a 40% reduction in cancer incidence after taking statins. What was the cancer incidence rate of the population? Was the test done on healthy 20 year olds who had a per capita rate of 100 cases meaning they prevented 40 people out of 100,000 from getting cancer? Percentages don't have much meaning to us if we don't have a baseline for them(2 votes)
- Why does consuming sugar and having a spike of insulin increase cytokines?(1 vote)
- Lets break this down. High levels of sugar over a long period of time will stimulate high insulin production (in someone who has the ability to make insulin aka, a non-Type I diabetic). Prolonged states of hyperinsulinemia will cause a desensitization of downstream cell regulators that cause the cells of the body to be less sensitive to insulin. This causes the sugar in the blood to not be absorbed by the cells.
Hyperglycemia for a prolonged period of time will actually cause sugars to deposit onto proteins in the blood. Commonly, we look to measure a diabetic patient's hemoglobin A1C, which is a longterm indicator for glycemic control. However, the sugars can also deposit on neurons, or in the retina of the eye. Aside from the side effects of this, the body's immune system will start to see the build up of these glycosylated proteins as foreign and begin to attack them. This causes the release of inflammatory cytokines systemically.(3 votes)
- is a stuffy nose, or when your nose is plugged...is that also a cause of inflamation?(2 votes)
- No this is caused by a build up of fluid in the sinuses(1 vote)
- How exactly does aspirin affect coagulation?(1 vote)
- Low-dose aspirin (acetylsalicylic acid, 81 mg) inhibits the enzyme Cox-1, which produces thromboxane A-2, necessary for platelet aggregation.(3 votes)
Video transcript
SALMAN KHAN: I'm here
with Dr. David Agus, who is a professor of engineering
and medicine at USC. DAVID AGUS: Um-huh. SALMAN KHAN: And we're
looking at pictures here of things that seem
very different to me. What is the
commonality right here? DAVID AGUS: The commonality
is inflammation. So inflammation can be manifest
by a runny nose in a cold or getting the flu. It could be manifest by
an infection in your toes. It could be hitting your
head playing football or hitting your arm when
you fall playing a sport. All of those can
cause inflammation. SALMAN KHAN:
Because inflammation has a certain meaning
in everyday language. At least when I
imagine it, it means something that's
swollen and red. But here, we're talking
about inflammation in more of the medical
or the scientific sense. Things are swollen and red
because of inflammation. DAVID AGUS: Right. SALMAN KHAN: And so
what is inflammation? It isn't just
swollen and redness. I mean, the football player
isn't getting swollen and red, or is he? DAVID AGUS: So inflammation is
when your body senses danger. So when something
is wrong, whether it be an infection, whether it be
trauma in the case of football players, whether it be
a cold, your body senses danger and sends in
its frontline soldiers, which are the immune
cells, in order to fight whatever's causing it. So if it's trauma, the
immune cells go in there and they help rebuild the
tissue that's damaged. If it's a bacteria,
they go in there and they try to take
away the bacteria so you can get over
that cold or that flu. And so that whole process
we call inflammation. SALMAN KHAN: I see. DAVID AGUS: It's
a danger process. SALMAN KHAN: So it's
the immune cells going to the sign of danger to
either fight the danger itself or repair the aftermath-- DAVID AGUS: Yup. SALMAN KHAN: --of the danger. So that sounds
like a good thing. DAVID AGUS: It's
an awesome thing. The problem is, your
body, all of us, we care about what happens
today, not down the road. SALMAN KHAN: Right. DAVID AGUS: And this
is 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. We call progeny. SALMAN KHAN: Right DAVID AGUS: It's not
about what happens when you're 80 years
old or 90 years old. And so inflammation is
fantastic about dealing with today's ramifications. The problem is if you
get the flu today, your risk of cancer and
heart disease a decade or two decades from now are up. SALMAN KHAN: If I
get the flu once? DAVID AGUS: If you
get the flu once. SALMAN KHAN: Really. DAVID AGUS: So those
five, six days-- SALMAN KHAN: You're worrying me. DAVID AGUS: --when
you feel horrible, your inflammation
is through the roof. That's having ramifications
down the road. SALMAN KHAN: Right. I mean 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. DAVID AGUS: I can tell
by looking at you. [LAUGHTER] SALMAN KHAN: You can
tell by looking at-- [LAUGHTER] And the symptoms that we get
when we have the flu or a cold, these are actually-- it's not
the virus that's-- the virus is causing the inflammation,
which is causing the symptoms. DAVID AGUS: Yeah. And that's what's wild. Is that when you get a virus,
your immune system attacks it and you get a fever. I still don't know
why we get fevers. It's one of those things
where the-- we call them the 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 really has looked at
the long-term ramifications. They look at short term. But how does it affect
a decade from now what's going to happen? We just don't know. SALMAN KHAN: Wow. Wow. And what you're saying
is that the reason why we have inflammation
is, yeah, something has happened to my body. I have some trauma, some injury. And you were saying
this to me earlier, you might have to run
away from a lion tomorrow. So fix Sal or fix
David up right now, so that he can run away
from the lion tomorrow. But in the wild, I might
only live 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 age of reproduction. DAVID AGUS: Eactly. The body has to
choose priorities. And the priority clearly is
today rather than tomorrow. And so an amazing study
was done in that we gave patients what
we call a statin. So statins were
drugs-- S-T-A-T-I-N. They were drugs that were
developed because they blocked the synthesis of cholesterol. SALMAN KHAN: Right. DAVID AGUS: And
we thought people with higher cholesterol,
particularly the bad one called LDL, those people have a higher
incidence of heart disease. So if we block the
synthesis, we're going to affect heart disease. And what do you know, we did. A dramatic effect, we lowered
the death from heart disease with these drugs. SALMAN KHAN: Right. So it seems like they worked. DAVID AGUS: They worked. Then a company, or
a very clever group, did a trial where
they gave people with normal cholesterol
these drugs. And they had a dramatic effect
in that it delayed heart attack and stroke by almost
a dozen years. SALMAN KHAN: Wow. DAVID AGUS: And it reduced
the incidence of cancer by about 40%. SALMAN KHAN: So
cancer, something-- I mean we don't
associate cholesterol-- DAVID AGUS: Totally different. SALMAN KHAN: Wow. DAVID AGUS: So it turns
out these drugs, which were the biggest drug in
terms of sales we've ever had, worked by lowering inflammation. So their effect in heart disease
wasn't by lowering cholesterol. It was predominantly by
lowering inflammation. SALMAN KHAN: Right. Right. DAVID AGUS: And the
effect on cancer was by lowering inflammation. In fact, do you remember
when the swine flu came out a couple years ago? SALMAN KHAN: Right. Right. DAVID AGUS: So if you
got the swine flu, the only thing that
protected you from your lungs collapsing and going on
what we call a ventilator, a breathing machine, was
being on one of these statins. SALMAN KHAN: Because it
would stop the inflammation. Because the swine flu
people were dying from is the inflammation going nuts. DAVID AGUS: Yeah. SALMAN KHAN: This
is fascinating. So the people who are
dying of heart disease, is it necessarily
the cholesterol that's killing them? Or is the inflammation
that's causing cholesterol? DAVID AGUS: Well, I think
it's this chicken and the egg phenomenon. That's it. The inflammation allows
cholesterol to deposit-- SALMAN KHAN: I see. DAVID AGUS: --and they together. SALMAN KHAN: I see. I see. So it's really the statin
affects inflammation, which then reduces cancer by
stopping the inflammation and stopping the-- DAVID AGUS: Exactly. SALMAN KHAN: --cholesterol. DAVID AGUS: One of those
problems we have a biology, in medicine, it's
what you can measure. And so I can
measure cholesterol. SALMAN KHAN: Right. DAVID AGUS: I don't
really know how to measure inflammation well. So while we can make these
association in big studies when we look back, if I had a
metric, if I had a blood test or something to look
at for inflammation, I can optimize things. SALMAN KHAN: Can you not measure
just the amount of cytokines and other inflammatory
type of things that become increased in
your-- does it happen? DAVID AGUS: You're right. But are different
types of inflammation. So some inflammation can
be good, some can be bad. Some can be really causal. Some could be a
little bit causal. And 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 have to optimize
it for a particular purpose. SALMAN KHAN: Right. Right. DAVID AGUS: So these were
optimized to lower cholesterol. And they do that very well. They also lower inflammation
and they work beautifully in that regard. But how do we optimize
that going forward? What it also means
is 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 things, like the flu shot. SALMAN KHAN: Right. DAVID AGUS: So
again, the flu shot will certainly delay you
from having or prevent from having bad flu. SALMAN KHAN: That's good today
and good today and tomorrow. DAVID AGUS: And tomorrow-- SALMAN KHAN: Yeah,
yeah, yeah, yeah. DAVID AGUS: --because it
limits heart disease and cancer down the road. That SALMAN KHAN: I had no clue
that the flu-- I thought it was just a nice thing,
avoid a week of sneezing, and you know. But the flu shot, you can
actually reduce your cancer-- DAVID AGUS: And heart
disease down the road. And we have to think
long term as a society. SALMAN KHAN: What about statins? I mean it seems like-- these are
drugs like Lipitor and Crestor. I mean would you-- I mean no one
should take our medical advice based on a thing in video. DAVID AGUS: Right. SALMAN KHAN: I mean are
people taking it just for heart disease or are people
taking it more broadly now? DAVID AGUS: Listen. I mean I'm a believer
that these drugs have such a profound
effect on cancer, heart disease, stroke,
potentially Alzheimer's, that you should consider taking
it to prevent these diseases. And again, we're giving
no recommendations. But what I say is
you, your parents, they should talk about
it with their doctor. And so why shouldn't
I be on this drug? SALMAN KHAN: Right. And there are some side effects. But they're easy to test for. DAVID AGUS: Test for, and
then they're reversible. SALMAN KHAN: Right. OK. So you're not going too-- DAVID AGUS: So
with anything, you got to do a risk and a benefit. SALMAN KHAN: Right. DAVID AGUS: And you
have to look at you and say am I high
risk for X, Y, and Z? If you are, what can
prevent or delay it? The name of the game is
not treating disease, it's preventing disease. SALMAN KHAN: Right. Right. Now, this is fascinating. Well, I might talk to
my wife about getting some-- well, no advice here. Everyone should talk
to their doctor. DAVID AGUS: By the way,
another great medicine to reduce inflammation
is called aspirin. SALMAN KHAN: Aspirin,
I've heard of that. DAVID AGUS: Yeah. It's a hell of a drug. Again, there are side
effects to aspirin. It can affect bleeding. But at the same time,
it's a dramatic effect by lowering inflammation. SALMAN KHAN: Right. And that is its
main side effect. I mean it's this age-old drug. It's a blood thinner. So if you get a cut or you bleed
while you're taking aspirin, you might bleed more. DAVID AGUS: Right. Blood thinner is a funny term. I'm not quite sure
what it means. I keep taking paint
thinner when you see it. SALMAN KHAN: Right. That's kind of how I imagine it. DAVID AGUS: It binds
to the platelets and blocks them from activating. It stops them from
working really well. SALMAN KHAN: So it's
more anticlotting. DAVID AGUS: Right. And platelets are one of the
key components of clotting. And they certainly affect it. SALMAN KHAN: Right. So your blood will have
the same viscosity. It just won't clot as easily. DAVID AGUS: Exactly. And you could certainly
paint a wall with either one. SALMAN KHAN: That's
a little morbid. All right. Well, thanks a bunch.