A weight loss study published in Nature Communications has shown a strand of protein is responsible for controlling the conversion of fat from useful fat the body can burn into fat which sits on the body as excess.
Protein MKK6 controls the conversion of fat stores, known as white fat into brown fat, in which lipids are burned to maintain body temperature and reduce obesity.
The research team analysed fat tissue samples from obese patients at the University Hospital in Salamanca, and found that these samples contained above-normal levels of the protein MKK6.
Therefore, having too much MKK6 in the body has been linked to obesity and the body’s propensity for holding on to the wrong type of fat.
Body fat is essential for maintaining an appropriate energy balance and regulating body temperature, but not all fat is the same.
The body contains two types of fat – white adipose tissue is a store of excess calories, whereas brown adipose tissue is considered a ‘good’ fat that burns lipids to maintain body temperature.
Dr Guadalupe Sabio, who led the research team, explained brown fat can be activated by cold to “generate heat instead of storing fat”.
He continued: “White adipose tissue can be converted into brown adipose tissue, thus increasing body temperature.”
This, Dr Sabio says, has led to increasing interest in the clinical potential of brown fat, since “activation of this tissue could reduce excess weight.”
According to Nuria Matesanz, the results of the study indicate that obese individuals lose the ability to activate brown fat or to convert white fat in to brown, and therefore are unable to lose weight via this route.
The researchers found that the inability to convert white fat to brown in obese patients is caused by increased amounts of the protein kinase MKK6.
By studying mice, they showed that MKK6 prevents the conversion white fat into brown.