Diet rich in sulfur amino acids may aid bowel healing

Short bowel syndrome (SBS) is a condition related to poor absorption of nutrients, which typically occurs in people who have had half or more of their small intestine removed.

Diarrhoea is the main symptom of SBS and can lead to dehydration, malnutrition, and weight loss, and researchers are studying ways to help the small intestine that remains after surgery adapt and function better.

And, according to a study, published in the December issue of The Journal of Nutrition​ scientists, based at Emory University, said that metabolism of sulfur amino acids may be important in alleviating SBS.

The authors maintain that these amino acids and their associated proteins are especially critical in the regulation of reduction-oxidation (redox) status and protecting the body from oxidative stress. Cysteine is the precursor to glutathione, a powerful antioxidant and also used to cleanse the body of toxins.

To study the possibility that consumption of higher amounts of sulfur amino acids might help prevent SBS after massive small intestinal resection, the authors studied its effect in rats.

Methods ​

According to the scientists, male rats were fed either a nutritionally adequate control diet or one containing a similar amount of calories and protein but elevated levels of sulfur amino acids (218 per cent of the cystine+methionine content of the control diet).

The researchers said that the animals were further divided into two experimental groups depending on whether they underwent a ‘sham’ surgery or a small bowel resection.

Because rats undergoing the more extensive surgery ate less than those with the sham procedure, and this difference could affect bowel growth indices, the investigators said that they employed a pair-feeding strategy.

They said that one week after surgery, the rats were killed and their intestinal segments were carefully removed and weighed, with sections of jejunum, ileum and colon microscopically examined, and analyzed for DNA and protein contents as well as biochemical indicators of sulfur-related oxidative state.

Results​

The data showed that bowel-resected animals consuming the sulfur-supplemented diet had a greater reduction in the redox potential of the GSH/glutathione disulfide pool in jejunal and ileal mucosa compared with those consuming the control diet.

The researchers claim that this effect was associated with significantly increased cellular growth in the ileal mucosa, a beneficial outcome in terms of intestinal absorptive following surgery.

They conclude that the study shows that greater consumption of sulfur-containing amino acids following intestinal surgery might be beneficial in terms of aiding healthy intestinal recovery, and that this may be partly due to influencing the GSH/GSSG reduction-oxidation system in the gut.

However, the researchers stress that further clinical studies will be needed to determine whether dietary sulfur consumption might decrease malabsorption due to SBS in humans.

Source: The Journal of Nutrition​
Published online ahead of print: doi:10.3945/jn.109.105130
Title: Dietary sulfur amino acid supplementation reduces small bowel thiol/disulfide redox state and stimulates ileal mucosal growth after massive bowel resection in rats.​
Authors: Y. Shyntum, S. S. Iyer, J. Tian, L. Hao, Y. O. Mannery, D. P. Jones, T. R. Ziegler