Month: June 2020

Imagine yourself as the head of a funding agency (like the National Institute of Health) in which your job is to look at proposals for research projects and decide what projects to award funding to. Based on your readings this term, discuss a research project (or projects) that you would be most excited about funding as they relate to learning more about microbial influences on human health. As part of your response, consider what are we likely to learn from the project and how that might be important in future healthcare decisions.

As there is a growing acceptance and understanding of mental health, I would be most excited to fund a research project which focused on the use of probiotics to relieve patients from symptoms of mental health disorders. We have learned that via the gut-brain axis, our mental health influences our gut microbiome and vice versa. Thus, I would expect to find that probiotics to restore gut dysbiosis would have positive effects on mental health, which in turn would have positive effects on the gut microbiome, forming a positive feedback loop. This would change healthcare by possibly increasing access to treatment of mental health for low income individuals, as access to drugs or therapists are very spendy. Furthermore, it would continue to legitimize the reality of mental health disorders as a serious health concern which requires treatment.

Part 1: Set a timer for 3 minutes, and make a list of as many human non-infectious diseases that you can think of that are influenced by microorganisms.

There are many human non-infectious diseases which are associated and influenced by microorganisms. Obesity, type II diabetes, asthma, Alzheimers, cardiovascular diseases, gastric cancer, ulcers, arthritis, autoimmune disorders, brain cancer and Parkinson’s disease.

Part 2: Refer back to your Writing Exercise #1 that you completed the first week of class. Reflect and discuss how your responses have changed from week 1 to week 10, and what the most important topics you will take away with you once you have completed the course.

When I first tried to list different non-infectious diseases, I knew almost nothing. I had been introduced to the gut microbiome in a previous immunology course, although the mechanisms of how it affected other diseases was not deeply discussed. Throughout the term, I know have an abundance of knowledge which contributes to my greater understanding that gut health is deeply intertwined with our own human health and is important to take care of. The most important topic in which I will carry away from this course is the focus on how to improve it through the use of pro-, pre- and synbiotics to encourage diversity and growth of my microbiome, while further limiting my antibiotic use to when necessary.

Can experiments detect differences that matter?

This question asked by readers of scientific literature is important because it seeks to ensure the results used to make a conclusion are valid. In the field of microbiology, for example, this can be seen when trying to understand functional differences between closely related genes versus sequences.

Does the study show causation or correlation?

This question is important to ask because while there may be correlation, it can be difficult to prove causation. One example which I have been always told, is that ice cream consumption is correlated with pool drownings. While these are correlated, it is clear that eating ice cream does not cause you to drown. Instead, there is a confounding variable of warmer weather; when it is sunny outside, there is both increased ice cream consumption and frequency of pool usage, and thus increased incidence of drowning. This can be applied to scientific literature because correlation almost always insists some type of causation, but the direct cause can be hidden or covered in the variables studied.

What is the mechanism?

This question asks readers to understand the conclusions on a deeper level before interpreting and analyzing the claims made by the scientific literature. Thus, understanding the mechanisms can help to determine if the study shows causation or correlation.

How much do experiments reflect reality?

This question serves to address the differences between the research in scientific literature and real life. For example, many studies cannot exactly replicate human microbiome, and use animal models or human cells. Thus, the results may not exactly translate to human health mechanisms. A general example which is common, is comparing the virulence factors of some bacteria is varying effectiveness in in-vivo and in-vitro studies.

Could anything else explain the results?

This question further explores the idea of correlation versus causation. Thus, it seeks to find other plausible confounding variables which influence the results found.

Microbial communities are hypothesized to influence mental health states via the gut-brains axis. The gut, which also known as the “second brain” is linked through several nerves and neurons to the brain. Thus cytokine production in response to microbes, as well as precursors for neurotransmitter produced to microbes, can then travel to and influence the brain. An example of this, is a study in which depressed mice whose vagus nerve was severed (removing the link between the gut and the brain), the symptoms of depression were no longer alleviated with probiotic use.

The brain and mental health states have also been found to, in turn, influence gut health. This is through the gut-brain axis, once again, and neurotransmitters, hormones, and steroids produced by the brain can influence the gut. One example is how catecholamines and norepinephrine during stress can travel to the gut and cause dysbiosis; there is an overall decrease in motility and nutrient absorption.

Thus overall, these relationships can influence health and disease because there are never ending lists and ways to promote mental health, which can then promote gut health and limit the risks of diseases associated with gut dysbiosis. On the other side, taking care of gut health can encourage a healthy mental state. Thus they can both promote health and disease by influencing on another.