MICE + ALCOHOL + SLEEP = CLEAN BRAINS

Night sky Manzanita OR by Abhinaba Basu July 2, 2013. https://flic.kr/p/f7njD9

SUMMER SCIENCE FRIDAY: MICE + LOW DOSE ALCOHOL + SLEEP = GOOD NEWS FOR BRAINS? MY FATHER –IN-LAW MENTIONED HE HEARD A RADIO REPORT BY A LOCAL FAMILY PRACTICE DOCTOR THAT 2 GLASSES OF WINE A DAY COULD PROTECT THE BRAIN FROM ‘BAD’ PROTEIN BUILD-UP.
 
The research article that had been referenced was from scientists at the University of Rochester Medical Center, published in the journal Scientific Reports in February 2018. The lead study author, Dr. Maiken Nedergaard and her colleagues had previously reported (Iliff et al. 2012) on their newly described system in the brain, called the 'glymphatic’ system, by which toxins and waste substances are removed.  Harmful build-up of proteins such as tau and amyloid-beta, associated with Alzheimer’s disease and other causes of dementia, are such substances.  
 
In the more follow-up recent study (2018) by the Nedergaard group, the effect of low and higher (medium) doses of alcohol on the brains of laboratory mice was studied, including the activity of the brain’s ‘glymphatic’ system.
 
Ananya Mandal M.D reported on the study in an article for news-medical.net, “Low dose alcohol everyday might actually ‘clean’ the brain”.  Results, she wrote, showed that when brains of lab animals were exposed to the higher (medium) alcohol dose, about 7.9 drinks per day, over a long period of time there was an increase in inflammation and a decrease in measures of cognitive and movement-related skills.   The brains of mice given low dose alcohol (equivalent of 2.6 drinks per day) showed lower levels of inflammation and an increase in activity of the ‘glymphatic’ system that the scientists claim ‘clean’ the brain. [A very high dose (about 21 drinks per day) was even more harmful].
 
Newsweek and CNBC also reported on the research.
 
The findings supported the existing impression that chronic long-term use of excessive alcohol was harmful to health and could lead to a decline in mental faculties, but that smaller amounts could be beneficial.  
 
While tempting to jump on board and take advantage of the positive spin on alcohol’s benefits in small doses and hazards in higher doses, there will need to be additional human studies before conclusions can be safely accepted without reservations. 
 
 In the URMC study alcohol was administered by injection into the abdomen of the mice; the animals did not take it by mouth. The low dose of ethanol purported to be beneficial (2.6 drinks daily/ 18.2. per week) is well above the Center for Disease Control and Prevention recommendations of a maximum of 1 drink per day/7 per week for women and 2 drinks per day /14 per week for men. The author clearly indicates, “Naturally, this study performed in mice should not be viewed as a recommendation for alcohol consumption guidelines in humans.” 
 
For purposes of fitness, adding 2+ (5oz.) glasses of wine to daily intake translates to roughly 350-375 additional calories. Best to wait for clarification as to a minimum dose that will result in benefits to the brain, and stick with the CDC recommendations until further guidance is provided by experts. It may be that  .5 to 1 glass will work just as well.
 
One of the most interesting observations made by the scientists in the original study, which first described the glymphatic system, is that it is activated during sleep and mostly quiet during awake periods. An URMC Newsroom piece that interviewed Dr. Nedergaard explained that the system was “almost 10-fold more active during sleep and the sleeping brain removed significantly more amyloid-beta”. 

Manila's article also mentioned that glymphatic system function has been shown to improve with exercise.
 
There is controversy regarding whether the 'glymphatic' or another system performs this function. Although the scientific community is struggling with the question of whether the system exists and does what its discoverers propose, the controversy has energized investigations in this area of neuroanatomy and physiology. 
 
If more is learned as a result of Iliff and Nedergaard’s team and others disrupting established thinking about the brain, more work can go into prevention and treatment of many conditions in which the removal of substances is impaired.  Think dementia, traumatic brain injury, and diabetes, to name a few.
 
The best news for fitness enthusiasts is that both exercise and sleep are likely to enhance the process by which the brain is ‘cleaned’.  We are learning additional ways in which adequate sleep is vital to top performance AND good health and longevity.  That low dose alcohol ingestion might improve the system means, for some, there’s an enjoyment which needn’t be eliminated for the cause of good health.
 
RUN & MOVE HAPPY!
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https://www.news-medical.net/news/20180205/Low-dose-alcohol-everyday-might-actually-clean-the-brain.aspx

 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3551275/

http://www.newsweek.com/drinking-healthy-alcohol-helps-clean-toxins-brain-study-shows-798169
 
https://www.cnbc.com/2018/02/02/rochester-medical-center-low-levels-of-alcohol-may-be-good-for-brain.html
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https://www.urmc.rochester.edu/news/story/3956/to-sleep-perchance-to-clean.aspx
 
https://www.cdc.gov/alcohol/fact-sheets/moderate-drinking.htm

https://www.nature.com/articles/s41598-018-20424-y
 
https://www.urmc.rochester.edu/news/story/5268/in-wine-theres-health-low-levels-of-alcohol-good-for-the-brain.aspx
 
https://www.medicalnewstoday.com/articles/320824.php
 
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5681909/
 
https://link.springer.com/article/10.1007%2Fs00401-018-1812-4