Sweet Brain O'Mine: How Sugars Help You Think!

Synaptic transmission, synaptic excitability, neuronal action potentials, neuronal firing, are just a bunch of fancy terms to describe the amazing phenomenon of chemical information streaming and flowing within your brain cells. You might have been told not to skip breakfast, since glucose fuels your mind and, along with a fair dose of caffeine, kicks you up to front the day. Well, the role of sugars in your brain unfolds far beyond that.

N-glycosylation, the chemical feature describing molecular sugary trees (glycans) linked to proteins, affects the functioning of many actors involved in synaptic-related processes, with multifaceted effects on synaptic physiology. For instance, the nervous system is full of diverse receptor proteins crucial for communication between brain cells, whose biophysical properties are affected by N-glycosylation, which thus helps in translating these molecular minutiae into behavioural, learning, and memory features. N-glycosylation is also able to influence the excitability of nerve cells, revealing novel roles of glycans in synaptic processes: neurotransmitter release, reception, and uptake are all markedly affected by N-glycosylation on several types of synaptic proteins.

Channel proteins and voltage-gated ion channels are proteins located on the surface of nerve cells. They act as gates for the chemical information flow in brain cells, controlling the responses to environmental stimuli, and many of them are also decorated with N-glycans, fine-tuning their performances. Given the wide chemical relevance of N-glycans in the central nervous system, is also not surprising how their dysfunction has been linked to many diverse degenerative brain disorders, like Alzheimer’s, Parkinson’s, and Prion diseases, among others.

Next time you have breakfast, think about the sugars differently! Some of them might be bad in excess, but there is a whole world of sweet architectures interacting and communicating in your nerves, shaping the biochemical information that nurtures your thoughts.