To follow up on one of Nate’s posts from 2010,hair grows not only on your skin. He describes a glomerular capillary to be
hairy. Glycocalyx, a hairy structure attached to the glomerular endothelium, is a mixture of glycosaminoglycans and proteoglycans. The
picture of glycocalyx accompanying that post is quite impressive.
Now we know these hairs are coated with another gel matrix
called endothelial surface layer (ESL). ESL,
together with glycocalyx, is believed to function as a barrier to prevent
protein passage from blood to urine. A recent article addressing this topic was
published in JASN.
called endothelial surface layer (ESL). ESL,
together with glycocalyx, is believed to function as a barrier to prevent
protein passage from blood to urine. A recent article addressing this topic was
published in JASN.
By using an animal
model, the authors showed that loss of ESL increases the sieving co-efficient
for albumin and that the degree of albuminuria correlates with the degree of
ESL loss (by the way their confocal microscopy images of ESL are pretty cool).
model, the authors showed that loss of ESL increases the sieving co-efficient
for albumin and that the degree of albuminuria correlates with the degree of
ESL loss (by the way their confocal microscopy images of ESL are pretty cool).
The implication of
the study is that it’s not just podocyte or GBM that are responsible for the
development of proteinuria; ESL, glycocalyx and endothelium appear to play an
important role as well. For example, loss of ESL has been reported in patients
with diabetes. Maybe it’s not just on the skin where hair loss occurs.
the study is that it’s not just podocyte or GBM that are responsible for the
development of proteinuria; ESL, glycocalyx and endothelium appear to play an
important role as well. For example, loss of ESL has been reported in patients
with diabetes. Maybe it’s not just on the skin where hair loss occurs.
For those who are interested in this topic, there is a nice
review article for further reading.
review article for further reading.
Posted by Tomoki Tsukahara
