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If you’re looking to start the year by  building new habits, there’s no better place to channel all that productive  energy than with today’s sponsor, Brilliant; check them out  at Brilliant.org/SciShow. [♪ INTRO] Tiny microbes, like cyanobacteria, can produce a lot of oxygen through photosynthesis. In fact, these critters are  thought to be the main reason for Earth to have enough oxygen to  kickstart multicellular life.

And now, researchers in Germany are  harnessing that power for another reason. They’re looking to reactivate oxygen-starved  neurons with the hopes that one day they can deliver oxygen to the  brain when it needs it the most. Brains need a constant supply of  oxygen to do their work properly.

And when not enough oxygen reaches  the brain, cells start dying out. So, scientists started to look at ways to  deliver that precious oxygen to the brain using things that can produce lots of  oxygen on-site, like green algae and cyanobacteria, collectively  referred to as microbes. To test out the hypothesis, researchers  used Xenopus tadpoles, tiny critters that have see-through bodies.

So, when the  moment came to kick off photosynthesis, scientists only needed to shine light on  the tadpoles’ translucent little noggins. After the tadpoles were anesthetized,  the microbes were injected into the heart. The circulatory  system then moved the tiny microbes throughout their blood vessels.

Then, the head was severed while in  a solution that kept the cells alive. After changing the solution to one  with low oxygen, the microbes i n the blood vessels surrounding  the brain were able to produce enough oxygen to jump-start the brain. And when the neurons struggled  to fire, the microbes helped restore the neuronal activity, kind  of like little internal generators.

But since this study only used tadpole  heads, there wasn’t a way to measure whether having these microbes in the  blood vessels surrounding the brain had any sort of negative impact  on the rest of the organism. And the authors bring up the point  that an intact organism’s immune system might not appreciate the presence of a foreign entity like a microbe and attempt to attack it. So, careful consideration would be  needed when selecting a microbe to use in future trials, as some species might  trigger a severe immune response.

As for when we’ll be able to  use this technique in humans, well, this is a long way off from being  tested in people for multiple reasons. First, this study would need to be  done on a whole human, not just a head. On top of that, humans aren’t  very similar to baby frogs, I mean, our heads are definitely not see-through.

However, our skin is, at least somewhat. The same researchers have suggested  that if you inject the microbes into the cardiovascular system, they  could get exposed to sunlight as they travel through the veins  and arteries just under the skin. But there’s a real risk of  these microbes clogging up an artery because they have a tendency  to clump together in one spot.

Also, too much oxygen can be  as bad as not enough oxygen, and how much is produced by  microorganisms is hard to control.   So, unfortunately, right now, this type  of research is only proof of concept. And a lot of work needs to be done for trials to move to creatures larger than tadpoles.   Luckily, other technologies have been  proposed to help with oxygen deprivation in humans, like injecting tiny  gas-filled microparticles directly into the bloodstream  to rapidly oxygenate the blood.   And although this isn’t quite as  cool as having algae living in your bloodstream, it could help  in a pinch in the future!   Something else that can help  in a pinch is problem-solving, and today’s sponsor, Brilliant, has  all you need to get you started. They’re an online learning  platform with courses about science, engineering, computer science, and math.

They have a recently updated course  on Scientific Thinking with hands-on experiments that let you  discover the world in a new way. Like, you might know that the water  boils at a certain temperature, but what happens when you add  salt, does the temperature change? If you want to find out,  visit brilliant.org/scishow or click on the link in the description.

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