Common belief holds that if a person overeats there is most likely an emotional catalyst for it, bearing out the old adage, “I ate my feelings.” However, neuroscience has long proven that suppression or enhancement of appetite is directly tied to neural circuitries in our brain. Furthermore, a new discovery made by researchers at the University of East Anglia (UEA) brings about the possibility of rewiring these appetite controlling circuitries and potentially offers a more effective solution to eating disorders such as obesity.
Regulation of hunger along with thirst, temperature, sleep-wake cycles, energy expenditure, hormone release, and other such key homeostatic functions are heavily (though not exclusively) modulated by the hypothalamus region of the brain. Damage or loss of neural cells in this brain region not only critically disrupts homeostasis — it is the leading cause for eating disorders like obesity.
Various medical conditions, from strokes to epileptic seizures, could lead to advanced damage of the hypothalamic cells. However, time is also a prime cause — as people grow older, appetite control cells in the hypothalamus will also degenerate, making increased hunger and potential weight-gain in all humans inevitable.
As if things weren’t grim enough, neuroscientists believed that hypothalamic neurogenesis within these appetite-controlling circuitries could only be generated during embryo development — in other words, the number of appetite-regulating cells in the human brain can and will only decrease.
However, new research published in the Journal of Neuroscience this week optimistically established that this may not be the case. UEA researchers found that a group of cells called "tanycytes" behave very similarly to stem cells and actually continually add new neurons to the appetite-regulating circuitries. This shows that the neural circuitry that modulates appetite is not fixed from birth, and could possibly be molded.
After this discovery, UEA and other researchers alike will want to focus on figuring out what regulates the behavior and activity of these tanycytes, and whether their numbers can be further manipulated to help control eating disorders.
Before UEA’s new findings, adult neurogenesis had only been observed in one other region in the brain — the hippocampus. Interestingly enough, the hippocampus’s main function includes memory and learning. Therefore, neuroscientists were able to link a physical process with an intangible element — the birth of memories and learning brings about a literal birth of neurons in the brain.
Neuroscience is a relatively new subdivision in medicine, and only recently have scientists taken to the brain to advance treatment for various disease such as obesity. Other diseases that have a neural basis include Parkinson’s, Huntington’s, Alzheimer’s, Autism spectrum disorders, agnosia, and many more. It is an important and flourishing field which has sparked interest and investment in the general public, including President Barack Obama.
Earlier this week, Obama announced BRAIN Initiative, a $100 million project that would map the brain’s neural processes and activities in an unprecedented manner.
The brain is the most vital organ of the human body, controlling everything from the way our muscles move to the direction of which our thoughts wander. Not only is it vital, it is also unimaginably complex and individualized — every human has an estimated one hundred billion neurons with several hundred trillion neural connection pathways that differ from individual to individual.
Damage to it could lead to diseases with devastatingly physical and mental symptoms. Current treatments to brain diseases veer more toward delaying rather than curing — with no current cures for disorders like Alzheimer’s or Huntington’s, attacks on the human brain are distinctly degenerative and will only worsen over time.
However, with newfound federal funding and exposure to neuroscience, researchers will hopefully be able to make more groundbreaking discoveries — like UEA discovery of tanycytes' generative nature — and further advance the treatment of disorders that have bases in the brain.