Effect of the BaroSense ACE Stapler procedure on food intake, food-reward, gastric emptying, hormone release, inflammatory profile, gut microbiota and behaviour towards food.

Obesity and its associated conditions have reached epidemic proportions.
Estimates are that about one third of the adults in the United States are
obese. At this moment there are many therapeutic approaches for the treatment
of obesity. But, efficacy of most treatment options are limited and so far
surgical intervention has been proven to be the only strategy to overcome
severe obesity. However, although bariatric surgery is the most important
treatment strategy at this moment, it had limitations and risks. Non-incisional
endoscopic procedures could minimize these limitations and risks.
BaroSense developed a new device, called the Articulating Circular Endoscopic
(ACE) Stapler, which can be used in the treatment of obesity. It*s a trans-oral
procedure, which intends to reduce the ability of the stomach to expand by
creating plications in the region of the fundus and the antrum. In contrast
with other bariatric surgery it is endoscopically performed, reversible and if
it fails most future surgical options are still open.
The main study (*Open, prospective study to evaluate the safety and preliminary
effectiveness of the BaroSense ACE* Stapler for the treatment of obesity*,
multicenter study (MUMC+ and AMC), accepted by METC AMC) seeks to determine the
safety and efficacy of this plicating system for patients with severe obesity.

In this sub-study we want to unravel the exact mechanism and provide more
information about the efficacy of the BaroSense ACE* Stapler. Therefore we will
measure changes in various parameters that are known to affect weight loss and
metabolism, before and after gastric plication (by using the BaroSense ACE*
Stapler) in overweight subjects (these parameters will only be measured at
patients in MUMC+). These parameters are post-prandial satiety, food-reward,
gastric emptying, food intake, satiety hormone release, behaviour towards food,
gut microbiota composition and inflammatory markers.

The mechanisms will be studied by two additional test days before, and two
additional test days after the procedure. We will be doing an MRI scan of the
stomach before and after the procedure and a meal tolerance test, also before
and after the procedure. The MRI scan will povide information on volume change,
accomodation and emptying of the stomach. During the meal tolerance test we
will collect blood samples, breath samples and VAS questionnaires before and
after a standardized meal.
Optionally, a fMRI of the brain will be conducted during the meal tolerance
test to assess food-reward and whether food-reward is influenced by the
procedure.

The additional risk of the substudy consists of two times two additional days
which will be spent at the hospital. There is hardly any additional risk. The
MRI scan is free of radiation and there's only an increased risk of hematoma
after collecting blood through the intravenous catheter instead of
venapunction. Additional risk of bleeding due to the biopsy of duodenal and
gastric tissue is very low.