Tuesday, December 7, 2010

Feeling Blue? Try a Dose of Blue Light at New Scientist

After a bit of a lull, it's been a busy week (and day) at Nathan Explains Science. This afternoon I have a new story over at New Scientist (link below) on using a blue-light activated, algae-derived protein called Channel Rhodopsin 2 (ChR2) to cure depression in mice.

(While you're checking things out, be sure to check out the posts from earlier today and yesterday, about flying—sort of—with light, more on basic problems with voting, and the first installment of Fielding Reader Questions.)

The gist is that a bunch of neuroscientists took depressed mice and implanted ChR2 in the medial prefrontal cortices (mPFCs) of their brains. They first "depressed" them—defining depression in mice is problematic, so they actually induced "social defeat stress—by bullying them. Perfectly nice lab mice had to endure the taunts of a bully mouse for ten days straight and had to interact with the bully directly for five minutes a day, at the end of which they were submissive, avoided contact, and so forth. It was, in short, kind of sad.

But then the happy part (before the unpleasant part that follows all such studies): shining blue light via an optical fiber on the mice's mPFCs, the team activated the ChR2, which, the biophysicists in the audience will know, improves ion flow and essentially helps depressed neuron firing along. And behold: the mice weren't depressed any more. Pretty awesome.

Here's the story.