Health and Medicine

Waste Product from Exercise is Good News for the Brain

Exercise

Scientists and virtually every discerning individual know exercise is good for the body. Thing is, we are all used to hearing about how some weirdly-named chemical substance is produced in copious amounts because of exercise, and how this substance is great for the body.

Therefore, you would understand why heads turned when researchers led by EPFL revealed that a waste product from working out is beneficial to the body. The actual head turner is that the benefit of this supposed waste product is very important in that it helps protect the neurons in your brain from trauma damage.

Lactate is the beneficial “waste product.” It is a waste product of the breakdown of glucose. It is mainly produced in the brain and muscles after intense exercise.

Typically, when an acute trauma (think stroke or a spinal cord injury) occurs, a negative process begins called excitotoxicity. The process causes toxic excitement of certain nerve cells. Two primary components involved in this damaging process are the NMDA receptors and the neurotransmitter glutamate, both of which interact with each other.

The role of lactate immediately after acute trauma is to protect the neurons against excitoxicity. To be accurate, previous studies have hypothesized that lactate has this effect. However, until now, how lactate performs this role had remained a mystery.

To establish the role of lactate in combating excitoxicity, the team tested the effects of glutamate (the injurious neurotransmitter) on neurons cultivated from the brains of mice. They used an advanced technique called Digital Holographic Microscopy that offers flexible visualization of cell structure and cell dynamics with nanometer-level resolution.

During the first stage of the test, the researchers tested how glutamate affected the mouse neurons alone. They recorded a 65 percent kill rate by the neurotransmitter. However, when the scientists added lactate, the percentage of neurons killed fell by half, to 32 percent.

On further probing, the team found out that lactate triggered production of ATP, the basic fuel of cells all over the body. ATP then binds to and activates a specific receptor in the neuron (in the brain), which triggers a cascade of complex defense mechanisms.

Thus, these defense mechanisms give the neuron much-needed armory to withstand the torrent of injurious signals from the NMDA receptor that would otherwise have laid waste to it.

The discovery may have vital applications in the realm of therapies and treatments following spinal cord injury, stroke, and other types of trauma. In addition, since several studies connect NMDA receptors to schizophrenia, epilepsy, Alzheimer’s and Parkinson’s, this discovery may also be vital in the renewed fight against some of humankind’s most unnerving medical foes.