Inhoud
Lecture 1 – Central nervous system development .................................................................................. 2
Lecture 2 – lung development and the effects of prematurity ............................................................. 12
Lecture 3 – pathways of bone formation and regeneration.................................................................. 23
Lecture 4 – muscle (protein) turnover .................................................................................................. 36
Lecture 5 – Hormones, growth and development ................................................................................ 48
Lecture 6 – mitochondrial theories of aging ......................................................................................... 62
Lecture 7 – Theories and hallmarks of aging ......................................................................................... 74
Lecture 8 – Aging and physical fitness ................................................................................................... 90
Lecture 9 – Alzheimer’s disease .......................................................................................................... 103
Lecture 10 – lung aging and COPD ...................................................................................................... 112
Lecture 10 – Hallmarks of cancer ........................................................................................................ 122
,Lecture 1 – Central nervous system development
The brain starts to develop around the 5th week, by 8 weeks the main structures of the brain and CNS
are already in place. By birth, the structure of the brain is already there but it is much smaller than an
adult brain.
The connections are really formed after birth, so the size of the brain increases very fast after birth
(90% by age of 6) but it still has to make connections. This can change by experience.
Overview of brain development stages by age.
The embryo begins as a flat disk which has 3 layers of cells from the ectoderm the nervous system
develops.
Neural plate -> neural tube -> brain + spinal cord
After the neural tube formation, basic forms of the brain are already coming into place. This starts
with the formation of the three vesicles. These vesicles also start to develop, two more vesicles start
to develop in the area of the forebrain and hindbrain. In these ventricles, the brain cells start to
develop.
The neurogenesis is majorly comprised by three stages:
, 1. Cell proliferation
2. Cell migration
3. Cell differentiation – into different neuronal cells
Cell proliferation
In the early stages you have the ventricular zone and the marginal zone which are two layers which
exist in these stages, here the most important things happen in the beginning.
From the ventricular surface, the stem cells that reside in the brain (radial glial cells) start to extend
their processes up towards the marginal zone. Along those, the body of the cell migrate upwards
where it can duplicate its DNA. After the DNA is copied, the cell retracts back via the processes and
because it has 2 copies it divides. There are thus 2 identical cells. This happens early in development
because you need a lot of cells that can generate brain cells.
Later in development, the division of these cells is not happening symmetrically but asymmetrically
so the daughter cells aren’t equal anymore. One of them stays in the ventricular cells (stem cells) and
can divide again to form the same cells but the other daughter cells start to migrate to become
actually brain cells (neural precursor cell).
The neural precursor cell is the initial neuron/astrocyte/oligodendrocyte.
, The radial glial cells are the progenitor (stem-like) cells that can generate both neurons and glial cells.
Early on, this asymmetrical division in which the neural precursor cells are develop they will develop
in neurons. Later in development they will develop into glia’s, this has to do with Notch.
Cell migration
These radial glial cells have large processes up to the marginal zone and along those processes the
neural precursor cell is migrating up towards the marginal zone. There the initial ones will reside into
the cortical plate and they will form the subplate.
The cortex does not form all at the same time but it consists of different layers, they develop inside-
out. The first layer that is formed, the new neurons migrate up and form a new layer on top of it. By
the end the intermediate zone with the processes turn into the white matter and the subplate
disappears eventually. The neurons/structure of the brain is now in place.
Lecture 1 – Central nervous system development .................................................................................. 2
Lecture 2 – lung development and the effects of prematurity ............................................................. 12
Lecture 3 – pathways of bone formation and regeneration.................................................................. 23
Lecture 4 – muscle (protein) turnover .................................................................................................. 36
Lecture 5 – Hormones, growth and development ................................................................................ 48
Lecture 6 – mitochondrial theories of aging ......................................................................................... 62
Lecture 7 – Theories and hallmarks of aging ......................................................................................... 74
Lecture 8 – Aging and physical fitness ................................................................................................... 90
Lecture 9 – Alzheimer’s disease .......................................................................................................... 103
Lecture 10 – lung aging and COPD ...................................................................................................... 112
Lecture 10 – Hallmarks of cancer ........................................................................................................ 122
,Lecture 1 – Central nervous system development
The brain starts to develop around the 5th week, by 8 weeks the main structures of the brain and CNS
are already in place. By birth, the structure of the brain is already there but it is much smaller than an
adult brain.
The connections are really formed after birth, so the size of the brain increases very fast after birth
(90% by age of 6) but it still has to make connections. This can change by experience.
Overview of brain development stages by age.
The embryo begins as a flat disk which has 3 layers of cells from the ectoderm the nervous system
develops.
Neural plate -> neural tube -> brain + spinal cord
After the neural tube formation, basic forms of the brain are already coming into place. This starts
with the formation of the three vesicles. These vesicles also start to develop, two more vesicles start
to develop in the area of the forebrain and hindbrain. In these ventricles, the brain cells start to
develop.
The neurogenesis is majorly comprised by three stages:
, 1. Cell proliferation
2. Cell migration
3. Cell differentiation – into different neuronal cells
Cell proliferation
In the early stages you have the ventricular zone and the marginal zone which are two layers which
exist in these stages, here the most important things happen in the beginning.
From the ventricular surface, the stem cells that reside in the brain (radial glial cells) start to extend
their processes up towards the marginal zone. Along those, the body of the cell migrate upwards
where it can duplicate its DNA. After the DNA is copied, the cell retracts back via the processes and
because it has 2 copies it divides. There are thus 2 identical cells. This happens early in development
because you need a lot of cells that can generate brain cells.
Later in development, the division of these cells is not happening symmetrically but asymmetrically
so the daughter cells aren’t equal anymore. One of them stays in the ventricular cells (stem cells) and
can divide again to form the same cells but the other daughter cells start to migrate to become
actually brain cells (neural precursor cell).
The neural precursor cell is the initial neuron/astrocyte/oligodendrocyte.
, The radial glial cells are the progenitor (stem-like) cells that can generate both neurons and glial cells.
Early on, this asymmetrical division in which the neural precursor cells are develop they will develop
in neurons. Later in development they will develop into glia’s, this has to do with Notch.
Cell migration
These radial glial cells have large processes up to the marginal zone and along those processes the
neural precursor cell is migrating up towards the marginal zone. There the initial ones will reside into
the cortical plate and they will form the subplate.
The cortex does not form all at the same time but it consists of different layers, they develop inside-
out. The first layer that is formed, the new neurons migrate up and form a new layer on top of it. By
the end the intermediate zone with the processes turn into the white matter and the subplate
disappears eventually. The neurons/structure of the brain is now in place.
