- An impaired gut microbiota can alter the brain's signals for appetite and satiety, and can influence obesity.
- Deep transcranial magnetic stimulation (dTMS) is a technique that sends magnetic pulses to stimulate specific deep regions of the brain.
- dTMS increased quantities of several beneficial bacterial species with anti-inflammatory properties and facilitated weight loss.
By changing the composition of their intestinal bacteria using a noninvasive electromagnetic brain stimulation technique, obese people can shed the extra pounds.
Deep transcranial magnetic stimulation (dTMS)
Deep Transcranial Magnetic Stimulation (dTMS) is the next generation of technology used to treat Major Depressive Disorder (MDD) and addiction. dTMS has been proven to be a safe and effective treatment for MDD and may have secondary benefits in patients with chronic low back pain by reducing pain related morbidity.
A Secret Cause of Obesity
An underlying cause of obesity may be an impaired gut microbiota composition, an imbalance in the complex mix of beneficial and harmful microorganisms that inhabit the digestive tract.
"We need new safe and effective therapies for obesity," said principal investigator Livio Luzi, M.D., professor and head of endocrinology at the IRCCS Policlinico San Donato and the University of Milan in Milan, Italy. "Despite numerous preventive and therapeutic interventions, none has stopped obesity from reaching epidemic proportions."
Luzi said scientists now know that an impaired gut microbiota can alter the brain's signals for appetite and satiety, or fullness. He and his co-workers studied whether dTMS could improve the gut microbiota composition in obese persons and, if so, by what underlying mechanisms.
dTMS Alters Gut Microbiota
In their study, funded by the Italian Ministry of Health, the investigators recruited three men and 11 women, ages 22 to 65, with obesity as shown by a body mass index (BMI) of 30 to 45 kg/m2.
They randomly assigned the study subjects to two groups for five weeks to receive 15 sessions--three times per week--of either dTMS (to the insula and prefrontal cortex deep in the brain) or a sham stimulation as a control. Before and at the end of treatment, subjects provided stool samples for microbiota analysis.
The research team also measured blood levels of glucose (sugar), insulin, pituitary gland hormones and neurotransmitters such as norepinephrine. Pituitary hormones play a key role in regulating appetite, and recent research shows that norepinephrine and other neurotransmitters affect microbiota composition, Luzi said.
- After five weeks of treatment, subjects receiving dTMS lost more than 3 percent of their body weight and more than 4 percent of their fat--significantly more than controls.
- dTMS-treated subjects had greatly increased quantities of several beneficial bacterial species with anti-inflammatory properties, such as are found in healthy people.
- Changes in the abundance of other bacterial species correlated with improvement of metabolic and hormonal parameters, including glucose, insulin, several pituitary hormones and norepinephrine.
- Livio Luzi et al., Magnetic brain stimulation causes weight loss by making gut bacteria healthier, ENDO 2017: The Endocrine Society's 99th Annual Meeting & Expo.