Brain Receptor To Regulate Growth And Puberty

Heights and puberty of people differ across populations and scientists have finally discovered the brain receptor accountable for our growth.

A specific brain receptor called MC3R is found to utilize the nutritional state to regulate growth and age at puberty in children and increases the lean muscle mass as per a new study at the University of Cambridge alongside teams from the Queen Mary University of London, the University of Bristol, University of Michigan and Vanderbilt University, published in the journal Nature.

Stress in Early Life may Influence Early Puberty Onset in Girls
Girls who do not reside with both parents from birth to age two are at higher risk of starting puberty at a younger age compared to girls living with both parents, reports a new study.

‘The way our brain receptor called MC3R, utilizes the nutritional state to regulate growth and age at puberty in children and increases the lean muscle mass has been discovered by a new study.’

Tweet it Now

The study thereby may explain how humans have been growing taller and reaching sexual maturity earlier over the past century. Data suggests that the average height of humans has increased by about 10 cm in the UK and up to 20 cm in other countries over the 20th century.

Some scientists suggest that this phenomenon could be related to more reliable access to food for pregnant women and children. However, a precise answer has not been found.

Brain and Hormones

Lower Testosterone During Puberty Increases the Brain's Sensitivity
Young men with lower testosterone levels throughout puberty become more sensitive to how the hormone influences the brain's responses to faces in adulthood.

Generally, hormones leptin (produced in fat cells & insulin) is known to signal the brain (hypothalamus) on body’s nutritional state by allowing the production of melanocortins from neurons (brain cells).

Among various receptors of melanocortins, the melanocortin 4 receptor (MC4R) is present in the brain that is known to regulate appetite, and lack of MC4R results in obesity.

Growth Hormone Plays a Critical Role in Early Puberty, Breast Cancer Risk
Girls who enter puberty early in life face a significantly higher risk of developing breast cancer later in life.

However, it does not control the effect of nutrition on the growth and timing of puberty. The study team thus finds another melanocortin receptor in the brain – melanocortin 3 receptor (MC3R) that is responsible for this action.

The MC3R system is found to control the release of key hormones in response to nutritional signals, thereby regulating growth and sexual maturation.

Brain Exercises to Improve Memory
An active brain can certainly help in improving memory by strengthening the connections between neural impulses in brain.

MC3R Mutation

This was proved in half a million volunteers in UK Biobank, where the genetic mutations in the MC3R resulted in shorter stature with delayed puberty on an average than those with no mutation.

Moreover, among 812 women with a mutation in one of their two copies of the MC3R gene, it was found that women who carried partial mutation were on average 4.7 months older at puberty than those without the mutation.

In addition, MC3R mutations resulted in shorter and lower amounts of lean tissue, such as muscle, but it did not influence how much fat these individuals carried.

To confirm these, 6,000 children from the Avon Longitudinal Study of Parents and Children (ALSPAC) were explored. Six children who had the MC3R mutations were found to be shorter and had lower lean mass and weight throughout childhood.

This phenomenon of linking adequate nutritional body stores to reproductive maturity through the MC3R pathway was further confirmed in mice studies. Hence, the study confirmed that MC3R is a necessary part of how the nutritional state controls sex hormone production.

“This discovery shows how the brain can sense nutrients and interpret this to make subconscious decisions that influence our growth and sexual development. Identifying the pathway in the brain whereby nutrition turns into growth and puberty explains a global phenomenon of increasing height and decreasing age at puberty that has puzzled scientists for a century Our findings have immediate practical implications for the testing of children with serious delays in growth and pubertal development for mutations in the MC3R,” says Professor Sir Stephen O’Rahilly, a senior author on the study and Director of the MRC Metabolic Diseases Unit at the University of Cambridge.

Source-Medindia