Scientists used human intestinal organoids grown from stem cells to discover how our bodies control the absorption of nutrients from the food we eat. They further found that one hormone might be able to reverse a congenital disorder in babies who cannot adequately absorb nutrients and need intravenous feeding to survive.
The authors found that the hormone peptide YY, also called PYY, can reverse congenital malabsorption in mice. With a single PYY injection per day, 80% of the mice survived. Normally, only 20% to 30% survive.
This indicates PYY might be a possible therapeutic for people with severe malabsorption.
Poor absorption of macronutrients is a global health concern, underlying ailments such as malnutrition, intestinal infections and short-gut syndrome. So, identification of factors regulating nutrient absorption has significant therapeutic potential, the researchers noted.
The authors published the work in Nature Communications, reported that the absorption of nutrients - in particular, carbohydrates and proteins - is controlled by enteroendocrine cells in the gastrointestinal tract.
Babies born without enteroendocrine cells - or whose enteroendocrine cells don't function properly - have severe malabsorption and require IV nutrition.
"This study allowed us to understand how important this one rare cell type is in controlling how the intestine absorbs nutrients and functions on a daily basis," the lead said.
One key finding of the study is how these cells, upon sensing ingested nutrients, prepare the intestine to absorb nutrients by controlling the influx and outflux of electrolytes and water, the researchers stated. Absorption of carbohydrates and protein is then linked to the movement of ions in the intestine.
For this study, the scientists relied on human intestinal organoid models. Grown from stem cells, organoids are small formations of human organ that have an architecture and functions that are similar to their full-size counterparts.
The study on malabsorption used three different human small intestinal tissue models - all derived from pluripotent stem cells, which can form any kind of tissue in the body.