Diabetes has become one of the top 10 killer diseases these days and has been taking a toll on the health of millions. How can you figure out the way to maintain a suitable diet and yet devour your favourite delicacies? To eat or not to eat? This might arise so many questions in your head. Well, don’t worry too much! Researchers, Jing Nie and his team from the Departments of Biological Sciences and Pharmaceutical Sciences in the State University of New York have helped you figure that out, using one of humans most despised enemies — RATS.
Surprisingly enough, we are no stranger to rats’ physiology as much as we think we are. We have similar bodily systems with almost 99% of shared genes, hence the reason to why rats were used in this research. They have been taken care of in a proper manner and have been used in this research with due respect to their sacrifice. The growth rate and the gene expressions of two different types of rats, normal, Wistar-Kyoto (WKY) rats and Goto-Kakizaki (GK) rats, which cannot digest glucose effectively and hence are diabetic in nature, were studied.
These two groups of rats were fed on two types of diet, a normal diet and a high-fat diet from three weeks of age. Their body weight and muscle weight were kept under surveillance until Week 20, week by week. Along with that, the strains of resistance of a protein known as insulin, that prevents our blood glucose levels from getting too high, on the rats’ genes were tested.
That’s a lot of information to digest isn’t it? Well, to make it simple, at this point we are very similar to these diabetic rats, even they can’t digest glucose. The muscle weight and the body weight were simply measured through the typical, normal method of using a balance. The complex part comes up when checking the amount of insulin resistance in their genes.
This is the part where the rats sacrifice their lives for the sake of protecting ours and lets us know the right diet for diabetes patients. The calf muscles of these rate were crushed into a powder form after they are killed to extract their RNA, a molecule which is responsible for our gene expression. Then, they were run through an agarose gel electrophoresis, a process in which these molecules can separate by size and charge. Just like a race, the smaller and more active molecules reach closer to the other side. This is done, to assess their purity. But a small portion of these RNA molecules is simply not enough to encode the entire DNA of that muscle or its gene. Thus, it was necessary for the researchers to “photocopy” them by the polymerase chain reaction. It works like a photocopying machine and creates several copies of the same strands of that RNA molecule.
The gene expression is can be represented as the RNA Volume as well. The volumes of RNA were documented using a device consisting layers of probe arrays which look like chips or wafers where you can insert RNA segments, a fluid station , a scanner and software data analysis to compute the data. The chips will contain certain RNA segments beforehand, which can fit with the RNA segments from the rats with insulin resistance genes by complementary bonding. If the insulin resistance genes are present, they will be complementary to the already existing RNA segments in the chips and a hybrid will be formed with these two segments. This way, we can compare the amount or the indices of these RNA segments between the two types of rats.
By doing all these, we would expect that the GK rats would have the highest growth in body and muscle rate. Contradictorily, it has been found that the WKY rats fed on a high fat diet had the highest growth rate in terms of body and muscle weight when compared to other rats. However, when looking into the indices or amounts of insulin resistance, the GK rats fed on a normal diet had the most insulin resistant genes. We can actually come up with a conclusion that a high-fat diet does not necessarily affect or worsen the effect of diabetes, rather it only affects us, normal people with regard to our body weight. Now, you know what to say when someone tells you not to indulge in fatty food. It is okay to savour them once in a while, undeniably, they taste so good.