Neurotoxins and Sleep

[TrevorC]

Hello everyone. My name is Trevor and i am new here. Nice to meet you all.

 

I have a question to ask. I was reading a book called "A mind of numbers". At some point in the book, the author states this:

 

"You may be surprised to learn that simply being awake creates toxic products in your brain. During sleep, your cells shrink, causing a striking increase in the space between your cells. This is equivalent to turning on a faucet—it allows fluid to wash past and push the toxins out. This nightly housecleaning is part of what keeps your brain healthy. When you get too little sleep, the buildup of these toxic products is believed to explain why you can’t think very clearly. (Too little sleep isaffiliated with conditions ranging from Alzheimer’s to depression—prolonged sleeplessness is lethal.)"

 

That caught my attention, and i started googling. Truth is i found a few articles but i don't know how valid they are. That is why i came to ask here. So is the above statement true? Or is it just a myth?

 

Thank you very much!

Edited July 18, 2017 by TrevorC

[CharonY]

While this is not my specialty, neurotoxins are generally only used when they specifically target and damage cells which, in this context is a bit of a misnomer as we are talking about regular metabolites that only become toxic due to accumulation. It is a fine, but significant distinction. What the author probably refers to is the glymphatic system. Its discovery is fairly recent and it is clear that the author you cited massively overstates the confidence in findings. As a side note, the bulk flow is not mediated by cells shrinking, that alone would not allow proper transport. Rather it is a mixture of pulsation of the vasculature and water flux from astroglial cells via activity of aquaporins.

 

But to reiterate, the physiological role is still under investigation.

[TrevorC]

While this is not my specialty, neurotoxins are generally only used when they specifically target and damage cells which, in this context is a bit of a misnomer as we are talking about regular metabolites that only become toxic due to accumulation. It is a fine, but significant distinction. What the author probably refers to is the glymphatic system. Its discovery is fairly recent and it is clear that the author you cited massively overstates the confidence in findings. As a side note, the bulk flow is not mediated by cells shrinking, that alone would not allow proper transport. Rather it is a mixture of pulsation of the vasculature and water flux from astroglial cells via activity of aquaporins.

 

But to reiterate, the physiological role is still under investigation.

Thank you very much for answering my question. I guess the title was wrong. The reason i wrote "neurotoxins" is because a few articles said that. I will go read a little about the glymphatic system, it sounds interesting.

[iNow]

Agree that the author embellishes the facts a bit, but sleep very much does have a role in the overall health of our brain and future likelihood of things like Alzheimer's. Lack of sleep leads to all sorts of problems, in large part because this "cleaning" process needs time to work.

 

http://www.npr.org/sections/health-shots/2016/01/04/460620606/lack-of-deep-sleep-may-set-the-stage-for-alzheimers

http://www.healthline.com/health/sleep-deprivation/effects-on-body

[CharonY]

Based on my reading (which admittedly is a few years old) the role of the glymphatic system in these processes is still a working hypothesis rather than established fact. That is not to say that there is no contribution, but one of the question is whether it is the main mechanism.

Edited July 19, 2017 by CharonY

[iNow]

Some of the more interesting reading I've done on this topic is collected here: http://neurosciencenews.com/neuroscience-terms/sleep-deprivation/

[iNow]

"In slow wave deep sleep, our glial cells rinse cerebral spinal fluid throughout our brain and this clears away a lot of the metabolic waste that accumulated during the business of being awake. One of things it can clear away is amaloid beta."

 

"We think Alzheimer's begins with the buildup of a protein called amaloid beta."

 

Quotes from Lisa Genova, neuroscientist discussing the concept of Prevention in a TED interview.

Edited July 22, 2017 by iNow