Sleep and diabetes and the kidney

Excerpt

We spend a third of our lives sleeping. And forever we have been speculating why?. Sleep is universal in vertebrates and has been described in invertebrates. The unraveling of this mystery started with the the discovery of “glymphatic” channels carrying toxic wastes in the brain. Prior to this, the only known waste disposal recognized was a recycling process internal to the neuronal cells themselves. Glial cells control the transport of CSF through channels in cell membranes. Since the energy required to transport across membranes is considerable it was clear that membrane transport and sensory processing were probably not occuring at the same time. A “downtime” from sensory processing was required to divert energy to perform housekeeping. After training mice to sleep on a two photon microscope and using real time iontophoresis Xie et al. found out that larger amounts of CSF flowed into interstitial brain spaces during sleep and to a greater depth than when awake [1]. The interstitial volume expanded by 60% during sleep leading to clearance of accumulated toxins such as beta amyloid (which is implicated in Alzheimer’s) twice as fast as when awake. Thus sleep is a state that prepares the brain for waking through obligatory self regulating cycles of brain states. …