Near infrared light brain simulates dopamine-producing cells

Trimmer PA et al, Reduced axonal transport in Parkinson’s disease cybrid neurites is restored by light therapy. Mol Neurodegener. 2009 Jun 17;4:26. doi: 10.1186/1750-1326-4-26.

This is an oldie but a goodie.  Researchers were able to use cells taken from people with and without Parkinson’s disease (PD) and then compare the way that these cells function. They knew that the dopamine-producing cells that are first affected by Parkinson’s have very long axons – imagine cables that connect one cell with a bunch of other cells in a distant part of the brain. They also knew that these long axons or cables are poorly insulated in all of us, and so they tend to be vulnerable to damage.

The researchers first checked an earlier finding, that in Parkinson’s these very long axons arising from dopamine-producing cells become less efficient in communicating with other parts of the brain. Yep, they clearly showed that PD-affected axons were deficient, compared with non-PD axons.

Having established this, they turned to the interesting part of their study, shining a short burst of 810nm (near infrared light) onto the PD cells. Suddenly the axons from these PD-affected dopamine-producing cells sprang to life, and started behaving as if they didn’t come from someone with PD.

Of course, once the effect of the 810nm wore off, the axons from the PD cells went back to their original dismal level of activity. No surprises there, as all the evidence shows that there needs to be regular bursts of red or near infrared light on the cells to get them fired up again and again. This is why Prof Alim Benabid and Prof John Mitrofanis developed the intra-cranial red light device in 2015 (like the deep-brain stimulation device only with red light instead of an electric current.)

So what does this research tell us? It gives more insight into how PD-damaged brain cells respond to the presence of red and near infrared lights. The batteries in PD-damaged cells, the mitochondria, get an energy recharge from red light, immediately sending fuel to these long, vulnerable axons along with a metaphorical kick in the rear-end. This mechanism shows that trans-cranial light, which penetrates a couple of centimetres into the outer brain tissue, can in fact have an effect on cells in the basal ganglia, where the problems first arise. Click here.