BioQuakes

AP Biology class blog for discussing current research in Biology

Author: organelle

CRISPR/Cas9 Provides Promising Treatment for Duchenne Muscular Dystrophy

There are nine kinds of muscular dystrophy and of these, Duchenne MD is the most common severe form of childhood MD. It affects about 1 in 5000 newborn males, only in very rare cases has it affected females. DMD is a genetic disorder that causes progressive muscle degeneration and weakness. Patients usually die by age 30 to 40.

DMD is caused by the absence of a protein, dystrophin, that helps keep muscle cells intact. In 1986 it was discovered that there was a gene on the X chromosome that, when mutated, lead to DMD. Later, researchers discovered that the protein associated with this gene was dystrophin. From this information, we can tell that this disorder is sex-linked, which explains why women are mainly carriers.

No one has found an absolute cure for this genetic disorder until now. Even in recent years, people have discovered treatments that will make patients’ lives more bearable, but never reverse the disorder. As a result of these advances, mostly in cardiac and respiratory care, patients are able to live past teen year and as long as in to their fifties, though this is rare. Although there are still drugs being tested like Vamorolone (a “dissociative steroid,” is an anti-inflammatory compound), more treatments on the molecular level are now being considered. However, thanks to recent discoveries and research with the new genetic technology, CRISPR/ Cas9, scientists may have found a treatment for DMD.

This new approach to gene correction by genome editing has shown promise in studies recently. This particular correction can be achieved in a couple ways: one is by skipping exon 51 of the DMD gene using eterplirsen (a morpholino-based oligonucleotide). Studies over four years show prolonged movement abilities, and a change in the rate of decline compared to controls. The newest approach to gene correction using CRISPR/Cas9, which the article I’m writing about focuses on, was performed in this study as next described: the CRISPR/Cas9 system targets the point mutation in exon 23 of the mdx mouse that creates a premature stop codon and serves as a representative model of DMD. Multiple studies in three separate laboratories have provided a path and laid the groundwork for clinical translation addressing many of the critical questions that have been raised regarding this system. The labs also discovered by further demonstrations, that this is a feasible treatment for humans. Functional recovery was demonstrated in the mice, including grip strength, and improved force generation- all of which are very important and hopeful discoveries. It is estimated from these studies that this new method will pass clinical trials and go on to benefit as many as 80% of DMD sufferers. Even greater success rates are expected if this is performed in young and newborn DMD patients.

Stress and your Gut Microbiota

Stress. It’s something all people deal with- whether in large or small amounts- we all know what it feels like. Stress doesn’t always mean staying up to pull an all-nighter and barely making the deadline for a paper, it can be just the anxiousness of flying and getting all your things packed before a trip. In general, stress messes with our immune systems in a lot of different ways. There’s a lot of research on the different ways that stress can affect our bodies ranging from our brains to our hearts. New research has shown another way that stress affects our immune systems: through our gut microbiota. What is our gut microbiota? Formally called gut flora, our gut microbiota is the microbe population living in our intestine. Research has revealed that this microbe population is extremely sensitive to any change in our lifestyles, stress included.

The number one thing that affects our gut flora is our diet. Our bodies are very sensitive to what we eat and how active we are. Problems in giving our bodies proper nutrition and exercise can result in mental health problems, diabetes, obesity, or cancer. Stress, however, has been shown to have a very big impact on our gut. An article reported in Medical Daily described a study done on wild squirrels. The researchers examined squirrel microbiomes and their stress hormone levels. They found that the more stressed a squirrel was, the less variety of bacteria in their gut. They concluded that a healthier squirrel would have more diverse gut bacteria. They assume the same is true for humans, but will have to test to verify. On a side note, they also conducted a test where they found that pregnant women under stress were found to transfer negative effects of stress to their children through vaginal microbiota.

220px-Eastern_Grey_Squirrel

Here is a possibly stressed squirrel  (although he seems happy eating the nuts).

Yet another study was conducted and published through The Atlantic on gut microbiota- specifically on “traveler’s constipation.” You might be wondering why I’m mentioning this because, let’s face it- who wouldn’t want to be traveling on a flight to the Bahamas right about now? For our gut, however, this can pose a lot of stresses we wouldn’t think about. About 40% of people say they suffer from travelers constipation, so let’s find out what this is all about. Firstly, on vacation our eating habits change. Whether this means coming home for the holidays and binge eating cookies, or eating a lot less than you normally eat, your gut is sensitive to both. Another, more surprising effect is the change of scenery- your gut is extremely sensitive to change of setting. Anytime you leave your general habitat, in fact, it throws your gut flora off balance- especially if the time zone changes because it messes up routine. For some, the mere thought of traveling can cause difficulty with their bowel movements. Sitting on planes or in a car for long periods of time can also really mess with your gut because part of what helps us “go” is moving around. This is why exercise can actually help you to go to the bathroom. All of these things are things we might not really think about because we don’t understand why it happens or we might not even realize it’s happening sometimes.

Our gut is often called the “second brain”, because millions of neurons line the intestines so it really does play a role in your mental state. Diet and exercise are extremely important in maintaining a healthy gut. Doctors and researchers have have recommended sleep, a lot of water, yogurt, probiotics or other fermented foods, foods high in fiber and meditation and mindfulness. These two might be surprising, but it makes sense. If our gut really is our “second brain” we should take really good care of our mental health through meditation, being mindful, and even therapy.

ANOTHER new study on Coffee

As students in high school, many of us are familiar with the immediate advantage of drinking coffee which is a decrease in fatigue and increase of alertness. Since I was young, however, I have heard many myths and hypotheses about the bad side effect of coffee, like how it stunts your growth and stains your teeth. I have also heard of other, positive side effect of drinking coffee. Some articles have said that caffeine has some positive effects against some diseases like Parkinson’s and Alzheimers. Multiple studies and published articles have come up throughout the years on the various side effects of drinking coffee daily and whether or not it is good or bad for you. An article published on sciencenews.org explains the most recent research on this mysterious drink and its long term effects on us humans, while another article argues its bad effects.

This article describes a study and analysis of more than 200,000 professionals followed for almost 30 years. They concluded that drinking up to five cups of either decaf or caffeinated coffee a day has a strong correlation to reduced risk of early death from heart and brain diseases as well as suicide. This study had even accounted for lurking variables such as smoking, weight, and diet. By adjusting for these factors, the scientists discovered that the benefits were more pronounced for non-smokers. They also found that both decaf. and caffeinated coffee were had positive effects. This led the researchers to believe that the powerful components of coffee may stem from chemical compounds in the bean such as diterpenes and chlorogenic acids.

Image of Coffee sourced from Coffee Greek.

Another article I came across mentioned the known positive, as well as the harmful effects of caffeine. (On a side note, I find it relevant to point out that this article mentioned that studies proving harmful effects of caffeine are harder to find that the reported positive effects. This, I speculate, might have to do a little bit with the fact that people tend to want to hear reassurance on things that will permit them to continue on with habits or actions that might be seen as harmful or bad otherwise.) This website cited studies that were performed by the Mayo Clinic that found that coffee raised blood pressure, increased risk of heart attacks, caused headaches, reduced fertility in women, proved harmful to people with type 2 diabetes, worsened menopause symptoms, increased anxiety, and, most obviously, caused insomnia and more. Some of these correlations, like an increase in headaches due to drinking coffee, can be explained by obvious reasoning: caffeine is a diuretic, and therefore if you aren’t drinking enough water to compensate, your body will produce too much urine and you will become dehydrated which leads to headaches in some cases.

Because of this drug’s popularity, studies after studies have come out presenting new, or sometimes repetitive, information regarding the side effects of drinking coffee. Many people want to believe that it is good for them because they drink it on such a regular basis that if it proved to be very harmful they would be in real trouble. Therefore, people are looking for proof that it is good, so there are more articles, credible and not, showing proof that it is. Additionally, another potential issue with these studies is the amount of caffeine given to the patients. In study one, the subjects were given around 5 cups of coffee a day, which is 2 to 3 more than the average American, and therefore unrepresentative of what Americans actually consume. From this data, I have decided to continue drinking the relatively small amount of coffee I do on a weekly basis, paying attention to how my own body reacts and noting the changes with attention in order to learn more about how it affects me personally, as I feel I am the only reliable source of information to myself at the moment.

The Real Scoop on Artificial Food Coloring

Although artificial colors and dyes have been used in foods since the early 1900’s, the FDA has banned many of them due to health concerns. Thirty-seven artificial colors still remain approved for general food use in the USA, many of which are now prohibited in some European countries. Many of these chemicals have been researched and found to have harmful side effects, but they are still used in popular candies, soft drinks, cereals, and other processed foods.

Americans are now consuming more processed foods and drinks than ever before, and therefore more artificial colors and dyes. Many scientists have researched these common chemicals and found shocking results. The most common blue 1 & 2, citrus red 2, green 3, red 3 & 40, and yellow 5 & 6, have been found to cause a wide degree of side effects. Some have been found to cause cancer, ADHD, neurochemical and behavioral effects, allergies and more. Because of link between artificial dyes and the frequently seen side effects of cancer and ADHD, many European countries such as Norway, France, Finland, The U.K., and Sweden have banned a number of these chemicals from their foods.

It is no secret that these additives have harmful side effects, so why do companies still choose to use them? It is a very simple marketing tactic. “You eat with your eyes”, therefore companies will try to make their food look visually appealing to convince you to buy their products. Using artificial dyes and colors is just one method companies use to attract buyers. Artificial dyes like Yellow 5 have more vibrant and concentrated color than natural ones like saffron or turmeric. They are also much cheaper than natural dyes because companies do not need to use much in order to get the color they want. Artificial colors are also easier to use and their results are more reliable because they are much less sensitive to heat than naturally-derived food dyes are.

Silly Rabbit

(A bowl of Trix cereal made with artificial colors and flavors. The new Trix will go on sale later this year, without its blue and green puffs.)

This news may seem very alarming and upsetting to the average consumer, but there is hope. The FDA requires that companies put their ingredients on the food labels, so you know which foods are organic and which ones have artificial coloring. Research on artificial food dyes has led many consumers to cut out harmful processed foods and sodas from their diet and led to more awareness among buyers. And although there are companies such as Coca-Cola that use harmful cancer causing dyes such like 4-MEI, there are brands like General Mills that are promising to soon cut out all artificial dyes from their cereals by 2017. The new direction American consumers are taking now towards organic and health foods is slowly leading the food industry to change their foods in a healthy way. No longer are some food companies looking for the most vibrant look with their presentation, but rather the healthiest.

 

 

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