Hello everyone. This is Dr. Weihong Pan from
BioPotentials Consulting in Sedona, Arizona in the USA,
the co-editor of this Henry Stewart series on the blood-brain barrier.
In this talk, I will provide an update of
the interactions of ingestive peptides with the blood-brain barrier;
Dr. Bill Banks has summarized the essential background in
his 2008 slide set for this BBB series of the Henry Stewart talks.
This past decade has seen many exciting paradigm shifts.
I will mainly discuss the progress on this subject post 2008.
Here is the outline of this talk.
First, I will continue from what Banks started in
his 2008 talk on the subject of ingestive peptides crossing the blood-brain barrier.
There are several points that I want to make.
The prototypical leptin reaches the brain mainly by saturable
receptor-mediated transport systems at the blood-brain barrier and blood CSF barrier.
Leptin also modulates the permeation of other ingestive peptides, particularly urocortin.
However, specific and separable transport systems are
not the only way by which ingestive peptides reach the CNS.
Some peptides may cross the BBB by simple diffusion, resulting from
relatively high lipophilicity and/or generate
secondary mediators at the level of the BBB endothelial,
though they, themselves lack meaningful penetration across the BBB.
Besides blood-brain and blood CSF barriers,
I will discuss the contribution of circumventricular organs, or CVOs in short,
and a neuroendocrine modulation of feeding.
Along with the retrograde axonal transport and the brain reward system,
brain barrier systems contribute to the regulation of feeding behavior.
Second, I will discuss glial biology regarding feeding and obesity regulation.
This is mainly based on studies originating from
our own laboratory and popularized in the past decade.
Third, I will briefly discuss the latest hot topic of the gut as a large immune organ,
and how the BBB is involved in gut-brain interactions in this aspect.
There are global changes in the BBB that occur during metabolic syndromes.
This is mainly shown by proteomic studies with follow up at mRNA,
protein, and functional levels.
I hope that these findings will provide a broad perspective of BBB mediated regulation in
obesity and neuro-inflammation that may eventually lead to neurodegenerative diseases.