C. Kuni:
> Related question: One of the adaptations of distance running is an 
> increase in the mitochondria of the runner's muscles.
> Has anyone seen any information related to the effect of the 
> Paleo Diet on the size and number of mitochondria, apart from 
> the exercise effect? I would think that, since our fat 
> metabolism occurs in these cells, the diet alone might 
> promote mitochondrial growth.  

Perhaps. That could provide one reason that Paleo dieters tend to feel more
energy even without increasing exercise levels.

On a related question, I have been curious whether mitochondria can be the
targets of immune system attacks in an autoimmune disorder, since
mitochondria have surface proteins called porins in their outer membranes.
Porins are also found in found in the outer membranes of Gram-negative
bacteria, of which mitochondria are a distant relative. It would seem that
an out-of-control human immune system might attack the porins in
mitochondria, given their similarity to porins in bacteria, but I don't know
if the immune system can penetrate the cytoplasm of human cells to get at
the mitochondria. Anyone know?