Q&A: Colon function decreases as we age
Dr John Broad, Professor Gareth Sanger and Professor Charles Knowles and colleagues, from the Blizard Institute published the results of their study on colon function last week.
The researchers found that the ability of nerves to cause muscle contractions in the colon decreases with age.
In this Q&A, Dr Broad explains the significance of the research and its implications for treating constipation.
What is new about the study?
This study of over 240 participants shows that as people get older, there is a decline in the ability of nerves to cause muscle contraction in the colon. The study was performed on samples of normal colon taken from patients undergoing operations for bowel cancer. We have shown that this decline occurs in the ascending part of the colon only, and is not associated with changes in the function of the colon muscles. We have also shown our findings were not affected by any medication our participants were taking.
The surprising finding from this study is that, as people get older, although we see a decline in the ability of nerves to cause muscle contraction in the colon, the number of nerves stays the same. We don’t lose nerves with advancing age, we lose function.
Why is the study important?
This is a very large study of human tissue. Most studies on the effects of age in humans are performed using relatively small numbers of tissue samples because these samples are taken from surgery and can be difficult to obtain. Translating findings from studies of animals can sometimes be misleading because animals have very different guts and diets compared to humans.
What are the wider implications?
With the knowledge generated in this study, it may be possible to treat constipation in elderly patients with different drugs than younger patients. Further studies will be required to investigate whether we can suggest different drug treatments based on age. This study is also an excellent demonstration of the feasibility of large, detailed, well-controlled studies using human samples, suggesting other studies could also replace the use of animals in biomedical research with human surgical specimens.
Broad J, Kung VWS, Palmer A, et al. Changes in neuromuscular structure and functions of human colon during ageing are region-dependent Gut Published Online First: 18 September 2018. doi: 10.1136/gutjnl-2018-316279