Burkitt and Trowell observed and then suggested that the African population was free of colonic cancer because of the protective action of dietary fibre. There has been much debate as to whether or not this is fact or fantasy. Epidemiological studies have been both supportive and dismissive of the fibre story. They preached that wheat bran was the fibre of choice.
Roediger wrote a series of papers suggesting short chain fatty acids, in particular butyrate generated in the colon by the fermentation of fibre were important in the metabolism and health of colonic cells . Butyrate was shown to inhibit DNA synthesis.
Another important observation was that acetyl salicylic acid ingestion was protective against the development of colonic polyps which are the precursors of colonic cancer.
With this background thee is a very interesting paper in the British Journal of Nutrition , vol 96, 2006, pp803-810. The authors, J. Kiefer, G Beyer-Sehlmeyer and BL Pool-Zobel show that short chain fatty acids modulated acetylaition in human HT29 colonic cancer cells. Acetylation of histones in the DNA of cancer cells has been associated with the reactivation or silencing of genes critical to cancer progression, differentiation and apoptosis. The activation of genes by inhibiting histone deacetylators ( HDAC) may be an important factor mediated by exogenous factors. It is also of interest that aspirin is an acetylator of cyclo-oxygenase. There maybe other enzymes and proteins that aspirin is involved in with acetylation of the protein and enzyme .
Such studies are so exciting in the development of nutrition. Proper experiments not conjecture.
- Martin Eastwood