Thank you. It was PD that made me aware of the huge importance of D3 in so many tissues.
Ther is along story of lower serum D3 in PD but its not an impressive difference, like your geographical insolation anlysis. Howerever there’s a lot more that can go wrong in D3 siganlling than serum level, lots of potential plausible reasons why PD may arise from errors in D3 signalling. Many oldies like me are D3-inadequate but only a few are PD.
Slide 11 and the reference cited are the link between D3 and PD. D3 combats Oxidative stress. Oxidative stress causing PD has a long history going back to the CA drug addicst (MPTP), and exposure to pesticdes such as rotenone. Berridge ( and others) are pointing the finger at the defences cells offer to oxidative stress. We may not need to have been poisoned if D3 levels are so low, or ineffective, in defending us against baseline oxidative stress. About 0.5% of oxygen in every breath ends up as reactive oxygen species, 24 /7. D3 provides very a large contribution to cells’ defences to those ROS.
D3 and other endogenous agents are the cornerstone of my experimental DIY ‘PD therapy’. I shall be describing them on my blog in the next few months, and will flag the posts here. As a cell biologist I approach it as I would a culture medium: what might my brain be lacking to help it combat ROS to function optimally. D3 is top of the list !