Last week I talked about the ways in which environmental factors influence the epigenome, and I wanted to expand on the topic a little more this week. We are currently in a period where obesity levels are rising and people are constantly watching what they eat, trying different diets in order to lose the extra weight. I thought it would be interesting to see how diet effects the epigenome and what consequences this has on the phenotype of the individual. Mischke and Plosch (2013) believe that a mother's diet while pregnant as well as the baby's diet when it is newly born influence the type of gut microbials that develop in the microbiome which effect the epigenetics of the individual.
Mischke and Plosch (2013) found that babies that are breast-fed tend to have lower levels of body fat than babies that have only been formula-fed. This initial diet is thought to effect the epigenetics of babies and result in lower body weights on average throughout life compared to individuals that were given a formula diet (Mischke & Plosch 2013). Different foods influence the content of the gut microbiome which affects the person's metabolism (Mischke & Plosch 2013). Folate and butyrate were observed in this study as both of them are metabolites that control epigenetics of the gut microbiome (Mischke & Plosch 2013). They are specifically involved with DNA methylation and histone modifications associated with intestinal cells, and play major roles in metabolism (Mischke & Plosch 2013). Microbials in the gut develop from the time a baby is born and diet has a large impact on the type of microbes that will form (Mischke & Plosch 2013). Breast milk introduces a type of bacteria that produces metabolites such as folate, while formula attempts to provide the same amino acids which causes there to be more proteins present in the microbiome (Mischke & Plosch 2013). The formula causes increased levels of butyrate to develop in the microbiome (Mischke & Plosch 2013). Folate regulates DNA methylation while butyrate inhibits histone deacetylases, so the two diets influence the epigenome in different manners (Mischke & Plosch 2013). Higher levels of the bacteria (bifidobacteria) which produced more folate were observed in people with lower body weight (Mischke & Plosch 2013).
The expression of genes through transcription is effected by the metabolites of the gut microbiota. DNA methylation helps regulate metabolism of lipids and glucose, and folate is needed for methylation to occur (Mischke & Plosch 2013). In order to produce enough folate, people need to maintain a diet that contains bifidobacteria (Mischke & Plosch 2013). This bacteria allows the gut microbiota to produce the metabolite which alters gene expression and allows the body to metabolize food more efficiently (Mischke & Plosch 2013). The addition of butyrate within the microbiome (possibly from formula diets) resulted in higher levels of fat as well as being associated with cancer and sickle cell anemia (Mischke & Plosch 2013). More research needs to be done on the effects of butyrate, but this metabolite was found to control the activity of genes (Mischke & Plosch 2013).
Miscke and Plosch (2013) determined that a baby's nutrition caused the development of certain gut microbiota and that the metabolites formed from the microbiota regulate the epigenetics of intestinal cells. Differences in transcriptional activity due to epigenome coding, resulted in specific phenotypes. Formula diets are thought to be linked to higher chances of the individual becoming obese through the alteration to the epigenome (Mischke & Plosch 2013).
That is very cool and a great way to finish off a discussion on a very complex, but highly fascinating topic! Thanks for all your insight and information in this newly emerging and exciting area. I’ve enjoyed reading your blogs and will keep a keen eye open for new developments in this field.
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