I must admit I haven't given my small intestine much thought recently. But as I've been ignoring it, it has been stretching and shrinking, tirelessly accommodating my variable food intake.
But what exactly prompts it to stretch has remained a bit of a mystery, one that a team of Stanford researchers now plans to tackle using a teensy micro-balloon, a tube-like structure designed to examine the insides of a fly. A Stanford press release provides some helpful background:
In both fruit flies and humans, eating stimulates intestinal cells to release a hormone closely related to insulin, which helps cells of the body take up sugar. This insulin relative produced by the intestines activates stem cell division, enlarging the intestines so they can absorb more food. The intestines of a starved fly or human, conversely, will shrink. This process is reversible and repeatable, allowing organisms to adapt to changing environmental conditions. Maintaining a large gut when food is not available is energetically wasteful.
While the role of the insulin-like hormone in regulating intestine growth is understood, what causes its release is not. Prior research has not been able to distinguish whether the hormones are generated as a result of the physical force of intestine stretching or the sensing of nutrients.
That's where the mini-balloon comes in. It could squeeze into the intestines to either stretch them or deliver nutrients, and then capture what happens next.
The research could eventually lead to better therapies for patients with short bowel syndrome or who are struggling with obesity, the researchers say.
Previously: Tension helps heart cells develop normally, Stanford study shows, Expert by experience: Living with, and teaching about, short bowel syndrome and Getting to the good gut: how to go about it
Photo by Cliff