"Food for thought" - On dietary intake, gene expression and physiology

There is a whole array of literature covering dietary habits and how they are or can be linked to gene expression and physiological characteristics; although scientists try their utmost to associate our everyday mundane activities to the well-managed physiological chaos that ensues within us, the fact of the matter is that these associations are very poorly understood and aren’t as simple and straightforward as they may seem when they are reported.

I recently read an article about how the smallest difference in dietary intake can make large differences in gene expression.

A couple of papers published in Cell based on research at the University of Massachusetts Medical School (UMMS) went in-depth about how subtle changes in the diet can trigger changes in metabolism and physiological characteristics. The study was carried out using model organisms, C. Elegans worms and the findings showed that there are regulatory pathways in existence that have strong communication networks that enable them to know what the external conditions are (a.k.a, small changes in food intake). This knowledge can alter the expression of these upstream regulatory factors and therefore lead to solid differences in gene expression. 

Reading this immediately reminded me of an article that I read around this time last year and for obvious reasons was immediately fond of.  It talked about how indulging in a carb-rich diet can ultimately lead to more weight loss, suggesting people have chocolate cakes for breakfast. 

Now, understandably, the two studies actually tackled different questions and attempted to answer them in different ways. Whilst one focused on gene expression and transcription factor regulatory networks which are autonomous within our own bodies (surely we have more important things to worry about than being responsible for switching on and off our own regulatory proteins with our conscious brain), the other study was mainly about experimenting with diets of human participants and had a psychological aspect involved at a much larger context. But surely these studies are interrelated at some level. 

I wondered, if small changes in diet and food intake sets off regulatory networks triggering different sets of genes being expressed, then surely the switch occurs despite the initial dietary change being made for breakfast, dinner or lunch? Why then, would it be okay to have carb-rich foods, even for breakfast?

Ultimately the fact is, as Dr Walhout, team leader of the studies that took place in UMMS put it, “It's very hard to answer questions about the complex interaction between diet, gene expression and physiology”.

How to figure out the mechanism of carbon capture and quicklime rehydration – Diamond Light Source X-Ray Diffraction to the rescue!

Carbon capture and storage is an essential part of recycling waste carbon, and ensuring it goes back into the carbon cycle. It is also beneficial for the environment because there is less atmospheric carbon dioxide present and therefore has a positive impact pn the global warming effect.

 

A low cost carbon capture method, which could be used by factories and power plants, underwent X-Ray Diffraction using a Diamond Light Source to study the process in deep detail. In situ X-Ray diffraction was used to make nanoscale observations on the specific details of the steps within the process of Carbon capture and rehydration of the Calcium Oxide.

The basic chemical reaction of the process is as follows:

CaO_(s) + CO_2(g) →  CaCO_3(s) 

The X-Ray diffraction imaging using the Diamond Light Source allowed a more precise and higher resolution view of the processes taking place, which led to insight towards how the Calcium Oxide (CaO) can be kept efficient even after several rounds of sintering, and how the hydration process can be tweaked to make this step efficient. Science Daily explained why it is necessary to study this process pretty well:

"after multiple capture and regeneration cycles, [Calcium Oxide's] capacity for capture decreases due to the loss of surface area through sintering, a process that fuses powders together to create a single solid object. Although the surface area can be restored through hydration, the material suffers a reduction in mechanical strength. If these problems can be overcome, CaO based materials could provide a low cost answer for carbon capture on a very large scale."

Although CaO based capturing of CO2 seems promising and is known to be low-cost, the reactions require temperatures of up to 800 °C which would mean this process needs the burning of a lot of fossil fuels.

However, the researchers who carried out this work explored and obtained a lot of information through the light scattering imaging results from the X-Ray diffraction, for example about the hydration process of the CaO.

Source: Molinder J et al. In situ X-ray diffraction of CaO based CO2 sorbents. Energy & Environmental Science (2012), http://dx.doi.org/10.1039/C2EE21779A