Let's take a look at the profiles, of the different types
of insulins that are on the market today.
So the rapid acting insulins, sometimes called the ultra
rapid acting insulins, are usually given at meal time.
There is three different major groups of rapid acting insulins.
There is the aspart insulin that peaks at 10 to 20 minutes,
there is lispro insulin that peaks at 15 to 30 minutes, and there is
glulisine insulin that will peak, a little bit later at about 20 to 30 minutes time.
The short acting insulins take a little bit longer but they
are still considered short acting.
These are the oldest of the insulins, and we call them
regular insulins. Trade names include Humulin and Novolin.
They peak at around 30 minutes to 60 minutes
and they last up to 4 to 12 hours.
The intermediate insulins lasts generally in the 12 hour range.
They peak at about 1 to 2 hours. We call them intermediate insulins, NPH insulins.
The long acting insulins, are the newest insulins out there
and they're really starting to become a mainstay of insulin therapy.
Detemir insulin peaks around 60 to 90 minutes, and lasts about
24 hours. Glargine insulin doesn't really have a peak time,
or at least that's what the marketing information says. There
is a bit of a spike at around 3 or 4 hours, but it's not really a
clinically relevant spike, it's only relevant on a pharmacology
chart, but from a practical point of view, it doesn't really have
a peak time and it also lasts about 24 hours. There are actually
new insulins out there, that are super long acting insulins
that now lasts about 36 to 48 hours, and we will briefly mention them today.
As time goes on, they are going to become more and more important.
Let's talk about the concept of glycemic excursion. So glycemic
excursion really means the difference, between the level
at the start of a meal, and at the end of a meal. So if you
take a look at your breakfast excursion,
that is the largest excursion of the day. Even though lunch
and dinner may be larger meals, there is not as much of an excursion.
This is going to be really important
when we start prescribing insulin.
I mentioned to you before that we do have some novel insulins
out there. The ultralong-acting insulins have just come on
to the market in the last, probably 8 months. Glargine modified
insulin has a very very long duration of action probably around 36 hours.
Now I also want to talk about inhalational insulins. These
very first products were very unsuccessful unfortunately.
You can see the first puffer, was really more like a huge
beer can than really a puffer. It was quite inconvenient.
It had the spacer built into the device. And it wasn't as
successful and it ended up getting pulled off the market because of
various reasons. There are new insulins out there that are
much smaller and perhaps a little bit more palatable,
and we'll see if they pick up and take off.
Now let's just review the actions of insulin.
The actions of insulin does not include.
Decreased protein catabolism in myocytes? Decreased protein
catabolism in hepatocytes? Decreased protein catabolism in adipocytes,
and increased triglyceride storage in adipocytes.
Which of these does insulin not include?
Well, increased triglyceride storage in adipocytes. That's
not a correct answer because we know insulin increases triglyceride.
Decreased protein catabolism in adipocytes. That's not correct.
Decreased protein catabolism in hepatocytes.
And decreased protein catabolism in myocytes.
So there you have the correct answer.