00:02
In this lecture we're going to discuss,
Inborn Errors of Metabolism in Children.
00:06
This is a very complicated field.
00:08
There are experts who specialize in this alone.
00:11
We're gonna try and shed some light in the complexity of this
and give some examples of errors of metabolism,
and hopefully make it a little bit easier to understand.
00:22
So here is glucose,
this is the essential building block with which we use
to create all the energy we need to run our bodies.
00:32
As you recall from biochemistry,
glucose will be stored in the liver as glycogen store, in glycogen.
00:40
Patients can have problems with storage of glycogen.
00:44
This family of metabolic disorders are glycogen storage diseases.
00:47
We'll talk about those.
00:49
Glucose is broken down into pyruvate through glycolysis
and of course in the other direction we have gluconeogenesis.
00:58
It is important to understand that that breakdown
can very rarely have some problems.
01:04
But that?s pretty rare because you can imagine
that if you're having a problem with glycolysis it's pretty hard to get by.
01:11
Glucose also is sent over to something called the pentose phosphate shunt.
01:16
The pentose phosphate shunt
is responsible for making NADPH and there is a disorder, G6PD,
which can cause problem with creating NADPH.
01:28
Because that diseases symptoms are almost entirely limited to red blood cells,
I wanno talk about G6PD during the hemo lectures which you'll see later.
01:39
Pyruvate is sent through the Krebs cycle to create ATP,
the energy for which most of our protein processes occur.
01:47
Don?t forget,
that?s also how we can feed into the fatty acid metabolism pathway
and we'll talk about some diseases of fatty acid metabolism as well.
01:58
Also, during fatty acid metabolism that?s how we make ketones.
02:04
Patients may have problems making ketones
and we'll talk about some conditions there as well.
02:10
The pyruvate is typically also sent over to start with amino acid metabolism.
02:16
Both metabolizing but even more perhaps handling amino acids
can be a problem with patient with amino acid disorders.
02:26
Some patients who have certain amino acids,
that they have a hard time digesting or managing in an effective way.
02:33
And don?t forget, amino acids may be disposed off
and in particular the nitrogen in amino acids
is disposed off through the urea cycle.
02:43
And patients can absolutely have urea cycle defects
and we'll talk about some of those as well.
02:49
So this is the overview for metabolic pathways,
and we're gonna focus on some common deficiencies in these pathways.