March 19th, 2019
2018 Summer of Science – High blood pressure and your kidneys: A look at how we can limit hypertensive kidney injury

Research Project

It is estimated by the American Heart Association that over 103 million American’s have hypertension, more commonly known as high blood pressure, which can have many adverse effects on the health of an individual. The kidneys are the filtering system of our bodies and work to remove waste and excess products every single day. When an individual has high blood pressure the vessels carrying blood within the kidney can become damaged and cause an inflammatory response that can lead to impaired kidney function and injury. My project looks at how we can block inflammation caused by high blood pressure and preserve kidney function. We do this by administering an antibody, a protein that can bind to specific targets to block their function, thereby reducing the inflammatory signals in rats that are hypertensive. Over a two-week period, we monitor blood pressure, food intake, water intake, body weight, and urinary output to provide an index of kidney function. At the end of the two-week period, we harvest the kidneys and utilize microscopy and video imaging to directly determine kidney blood vessel function.  Using this approach, we can determine if the antibody treatment is protecting the kidney from hypertensive injury.  This information allows us to understand how inflammatory signals influence organ function and develop new targets for medications for individuals with high blood pressure.

Realities of Research

My experience in my research lab this summer has been pretty different from my past research experiences. My research in the past has focused mainly on cell culture and use of a mouse model for my work. This summer I utilized a rat model and equipment I was not accustomed to working with, such as, machines that measure rat blood pressures. With my experience, there was a bit of learning curve and presenting my project progress weekly at lab meetings was very intimidating at the beginning.  Shifting my focus to physiological research this summer also posed some challenges. When utilizing an animal model in physiological research there are many variables you have to account for. Most of these variables are out of your control so variation between experiments was common. Overall, this experience has helped shape who I am as a scientist and taught me how to successfully overcome obstacles. My project has produced promising data that suggests that inhibiting inflammation in kidneys that have been exposed to high blood pressure helps to preserve kidney function.

Life of a Scientist

A good day in lab usually consists of me coming into lab around 8AM and leaving around 5PM, but most days I find myself coming in early or leaving much later. I usually will take some work home with me but I always make sure I designate at least an hour every night to myself where I relax, catch up with friends, or catch up on my favorite shows. Although I tend to always be stressed about school work or a deadline, it’s made easier by the fact that I enjoy my work and what I study. I think the most rewarding part of any research undertaking is when you finish a project or find some promising data that help contribute to new scientific discoveries. Having an amazing lab team working alongside me also helps. I received some excellent guidance from many of the mentors in lab and especially from my PI who taught me the importance of oral and written scientific skills. I think it’s great having a close-knit group of individuals in lab that are always willing to help you succeed and help you troubleshoot an experiment when it does not work.

 

Brian Freeman is a senior at the University of California, Merced majoring in Biology with an emphasis in Microbiology and Immunology. He is a 2018 Short-Term Research Education Program to Increase Diversity in Health-Related Research (STRIDE) Fellow working with Dr. Edward Inscho at the University of Alabama at Birmingham. His fellowship is funded by the APS and a grant from the National Heart, Lung and Blood Institution (Grant #1 R25 HL115473-01). Upon graduating, Brian plans to enter a Biomedical PhD program and pursue a career in academia.
March 12th, 2019
Seal Tissues, Antioxidants, and -80 Degree Freezers

Research Project

The Weddell Seal is able to hold its breath for 30 minutes at a time while diving in frigid Antarctic waters. To avoid running out of oxygen during this long dive, the seal collapses its lungs and restricts blood to only essential organs. In other mammals, the process of cutting off blood flow and the supply of oxygen to a tissue, only to reoxygenate those tissues at a later point (when the seal resurfaces) generates reactive oxygen species. The process causes oxidative stress, which damages the tissue. This summer I am studying some of the physiological adaptations that enable Weddell seals to avoid the detrimental effects of oxidative stress at a cellular level. At the moment I am focusing on catalase, an antioxidant enzyme that is good at breaking down hydrogen peroxide (a reactive oxygen species), to see if its activity is higher in seal tissues than in other mammals. The long-term goal of this research is to apply our understanding of how seals cope with oxidative stress to human organ transplants.

Realities of Research

This is my first time working in a lab so most everything has been entirely new to me, from the constant buzz of the -80 degree freezers to the techniques of growing cells to the precise technology. Besides learning many science skills, I’ve spent the last several weeks seeing how rare (and exciting!) it is for an experiment to work and yield significant results. Fingers crossed for the rest of my project!

Life of a Scientist

Besides working on my own research, I’ve been involved in numerous projects throughout the lab, so I’ve seen how research questions evolve and overlap and shift as researchers collaborate with one another. The aspect of collaboration within my lab has been one of the coolest things to witness this summer, especially since each researcher is doing distinct work. I’ve also loved getting to know my coworkers, and we’ve had cool conversations about new scientific discoveries and endless career options.

Throughout the summer, I’ve really appreciated being able to hold on to a big picture – of the real, live seals – even as I work at the microscopic, cellular level. I think this seal research is pretty darn cool.

 

Eliza Skoler is a senior Biology major and Neuroscience minor at Carleton College in Northfield, MN. She is a 2018 UGSRF fellow working in Dr. Allyson Hindle’s lab at Massachusetts General Hospital in Boston. She plans to pursue a career in public health.
March 7th, 2019
Investigating the role of the androgen receptor in polycystic ovarian syndrome

Research Project

For the past summer, I have been working in laboratory of Dr. Sheng UW at the Johns Hopkins School of Medicine. In the Wu lab, we are investigating the etiology of polycystic ovarian syndrome or disease (PCOS/PCOD). One of the major clinical presentations of PCOS is high levels of androgens, a condition known as hyperandrogenism, and the Wu lab focuses on the androgen receptor (AR) which binds to androgen outside of cells and acts inside the cell to express certain genes. The mouse model that we use mimics hyperandrogenism by exposure to dihydrotestosterone (DHT), which is present in low amounts in women without PCOS. To investigate mechanisms of hyperandrogenism and the AR, knockout mice without the receptor are compared to control mice, enabling us to investigate the effects of differential levels of DHT and the role of the AR on fertility, gene expression, protein and RNA levels, adipose tissue, and ovarian morphology (Wu et al., 2014). Despite the prevalence of PCOS in women of reproductive age, and its association with metabolic dysfunction, infertility and hirsutism, the exact cause is not known and effective treatment options are not available. By elucidating the pathophysiology of PCOS, treatment can be designed to target the cause as opposed to only clinically managing the symptoms temporarily.

Realities of Research

Although the prospect of doing research in a lab might sound like it involves the use of expensive equipment and the newest technology (and in many cases this is very true), a large portion of research involves spending hours maintaining and genotyping new litters, waiting for assays and reactions to finish, and pipetting hundreds of samples. Experiments sometimes work, and at other times they fail and must be repeated. Small errors in pipetting or mindlessly forgetting to include a certain solution can cause time-consuming experiments to fail. But, the most critical learning experiences I have had thus far were assessing what went wrong and fixing it by. Results are also not immediate; it takes several weeks before the effects of DHT can be assessed. Confirming the genotypes of our mice is critical to make sure that we are investigating what we claim to be, and ensuring DHT surgeries are done at the correct time requires attention and organization. Preliminarily, the effects of DHT we have observed have been physiologically plausible, although much of the data collection of the study is still ongoing.

Life of a Scientist

Simultaneously, the best and worst parts about doing research in a lab are that the hours are flexible and I can plan my week. But, this also means spending evenings working due to long wait times for experiments that extend past the usual 9 to 5 working day, or because a protocol calls for a certain experiment to be done at a certain time. The independence is exciting, but can also be intimidating as I must be aware of what needs to be done and when. However, research is collaborative. As the youngest and most inexperienced person in my lab, I am always learning how to do new experiments and how to interpret and analyze data. Others are always offering me tips and tricks, supporting me when I fail, and helping me deal with my constant fear of getting bitten by mice. The most rewarding moments of the summer so far have been presenting data to my PI and co-PI, and teaching members of the lab how to complete a computerized tissue analysis that had not been done in our lab before. The most disappointing? Waking up early to complete a western blot protein analysis only for it to fail – not once, but multiple times!

References:

  1. Wu, S., Chen, Y., Fajobi, T., DiVall, S., Chang, C., Yeh, S. and Wolfe, A. (2014). Conditional Knockout of the Androgen Receptor in Gonadotropes Reveals Crucial Roles for Androgen in Gonadotropin Synthesis and Surge in Female Mice. Molecular Endocrinology, 28(10), pp.1670-1681.
Gopika Punchhi is a rising senior at Johns Hopkins University in Baltimore, MD, pursuing degrees in Molecular and Cellular Biology and Public Health Studies. Through the Undergraduate Summer Research Fellowship (UGSRF) program, she is spending the summer working under Sheng Wu, PhD, an associate professor in the department of Physiology at the Johns Hopkins School of Medicine. UGSRF is funded by the APS. Gopika plans on attending medical school to become and gynecologist or endocrinologist, while also continuing involvement in molecular and population-level research in these fields.
February 26th, 2019
Sex Differences in Asthma

Research Project

This summer, I was involved in research with Dr. Silveyra at Penn State College of Medicine. We looked at microRNAs, which are small pieces of RNA involved in various processes in the cell, including regulation of how much of a certain protein is made. MicroRNA-106a is a microRNA that influences asthma in mouse lung immune cells, which cause inflammation. miRNA-106a does so by preventing an anti-inflammatory protein, IL-10, from being made. Because we knew that more adult females have asthma than adult males, we hypothesized that miRNA-106a would also be expressed differently between males and females. To investigate this hypothesis, we allowed several mice to develop asthma by repeatedly exposing them to house dust mites for 5 weeks. We then exposed the mice, along with additional mice that did not develop asthma as a control, to either ozone or filtered air for 3 hours. After that, we harvested the lungs and extracted the RNA from the tissue. We separated out miRNA-106a from the total RNA and determined its relative amount compared to the amount of another RNA that is always present in cells. We discovered several differences in how much miRNA-106a was present between males and females within treatment groups. Along with other factors, these differences in miRNA-106a levels in mice may play a role in the differences seen in human asthma, which affects about 8% of all people in the US. It could even lead to a new treatment for asthma that is specific to men or women.

Realities of Research

Doing research full time in a lab was more enjoyable than I expected. Each day looked different for me in terms of the tasks I needed to complete. I learned several new techniques, including RNA extraction and real time PCR, and I used these techniques very frequently throughout the summer. During the experiments, we had to repeat our real time PCR plates several times due to a lot of random error, and we had to repeat the RNA extraction for several samples because we didn’t get the amount of RNA we wanted. It was a long process, with many setbacks, but we finally got results from our experiments. We did see differences in the amount of miRNA-106a between males and females, but we did not see the differences that we expected. Because of this, we understood that miRNA-106a may not be causing all the differences seen between men and women with asthma, but other factors may cause the differences as well.

Life of a Scientist

As said earlier, the part I most appreciated about my summer as a scientist was that each day brought new tasks. However, experiments can take a long time to complete, with several setbacks and problems that need to be addressed along the way. There is no instant gratification; I had to work for every bit of data I had. But it is still rewarding when one can publish or present research at a conference, and other scientists listen and ask questions. To be a scientist, one must know how to work as a team and communicate clearly so everyone understands what their role is in the lab. I felt that my team was very good at doing that, and our lab environment was better for it. My lab team was a huge help to me in teaching me techniques, assisting me in carrying them out, and helping me to make sense of my results. All in all, the life of a scientist, though with many obstacles, is rewarding, and I would encourage anyone to check it out.

Rachel Steckbeck is a junior at Messiah College in Mechanicsburg, PA. She is a 2018 Undergraduate Summer Research Fellow (UGSRF), and worked in Dr. Silveyra’s lab at Penn State College of Medicine in the summer of 2018 for 10 weeks. UGSRF is funded by the American Physiological Society. In the future, Rachel hopes to attend medical school and work at a local hospital or practice.
February 19th, 2019
Ways to reduce Myocardial Reperfusion Injury

Research Project

This summer I am working in the Department of Anesthesiology at Stanford University. The main aim of my assigned project is to study the role of TRPV-1 (Transient Receptor Potential Vanilloid-1) in myocardial reperfusion injury. TRPV-1 is considered as a main channel that mediates cellular responses to different stimuli such as pain and heat. Regulation of TRPV-1 is important because it controls mitochondrial membrane potential and reperfusion injury. Modulation of TRPV-1 interaction site with calcineurin is essential to reduce the injury. My main objective for the summer is to study the effect of previously synthesized peptide drugs on the interaction of TRPV-1 with calcineurin. We hope that this project will help to reduce damage from cardiac reperfusion injury since it is responsible for up to 50% of myocardial infarct size.

Realities of Research

Stanford was my dream and I spent this summer in this dream. As I had an inadequate knowledge in the real physiological lab before, I was lucky to have an opportunity to experience many new techniques and skills. The most captivating experience was rats. Unfortunately, my home university does not have animal resources and students are deprived of working with animals. Hence I am planning to pursue PhD next year, I was very anxious about my incompetence and inadequacy. Luckily, my assigned project for the summer required me to isolate fresh cardiomyocytes from adult rats and perform different cell death assays on them. I was very excited about upcoming surgeries but forgot about one significant nuance- rats itself. Rats were afraid of me, so do I. Ironically, my fear made them even more stressful, so eventually I ended up with zero cells. I repeated surgeries dozens of time forcing myself to be braver and bolder. After continuous failure, I got used to them and I am obtaining enough cells these days to continue further. Now, I understand that any skill can be acquired with determination and perseverance unless it is highly desired.

Life of a Scientist

People do the science for many reasons. For some, it gives a prestige and high social status, but for some, it gives a hope for the better future. When I first told my family a decision of becoming a scientist and pursuing an academia, I was warmly welcomed with benevolent joy about my safe future. For sure, being a scientist seems to be the most auspicious occupation for women hence it requires neither intense physical nor intellectual activity. That was when my first fairytale illusions about the science career have started. Years later, after experiencing both flukes and failures I understood that life of a scientist indeed requires something very special- struggle with Yourself.

Coming to the lab every day and continuously repeating the same routine experiments over and over again can frustrate even the nerds. But for me, this is a real beauty of the science. When the experiments don’t work for weeks and the moment when you start quitting, surprisingly everything begins to work by lucky chance. You get happy and renew the cycle from the very beginning without even a tiny memory of those hapless days. Ironically, the cycle goes on further and combo of successful/unsuccessful experiments continue to form a chain reaction in your life. I agree with Mare Curie that “A scientist in the laboratory is not only a technician: he is also a child placed before natural phenomena which impress him like a fairy tale”. If you still believe in miracles and get amazed by the natural laws, follow your passion and just chase the science!

 

Reference

Hurt, C.M., Lu, Y., Stary, C.M., Piplani, H., Small, B.A., Urban, T.J., Qvit, N., Gross, G.J., Mochly-Rosen,D.,  Gross, E.R. Transient Receptor Potential Vanilloid 1 Regulates Mitochondrial Membrane Potential and Myocardial Reperfusion Injury. J Am Heart Assoc 5(9), 2016.

Zhuldyz Zhanzak is a senior majoring in Molecular Biology at Nazarbayev University, Kazakhstan. She is a 2018 Undergraduate Research Excellence Fellowship (UGREF) Fellow working in Dr. Eric Gross lab at Stanford University School of Medicine, CA. Zhuldyz’s fellowship is funded by the APS. Following the graduation, Zhuldyz plans to pursue PhD in immunology and follow a career as a scientist in the academia.
February 12th, 2019
Hypertension Prevention: does it also improve motor cognitive function?

Research Project

This summer, I’m studying the effects of inspiratory muscle strength training on motor and cognitive function in middle-aged to older adults. Motor function is the ability to move the muscles in your body, and cognitive function is your brain’s ability to perform tasks. Inspiratory muscle strength training, or IMST, is a relatively understudied technique of exercising the muscles you use to breathe in. By breathing in, or inspiring, against a resistance with a small device that looks similar to an inhaler, you can make these muscles stronger and hopefully improve many bodily and cellular functions, including motor-cognitive function. What is currently known about IMST is that it can significantly improve blood pressure in healthy adults (DeLucia, De Asis and Bailey, 2018), but its effects on adults with high blood pressure have not been tested yet. The IMST study on the large scale is focusing on the possible blood pressure and cardiovascular benefits of IMST in adults with high blood pressure, and I’m focusing my research and data analysis specifically on the motor cognitive functions that we also test.

Because a decline in motor-cognitive (shortened to motor-cog) function is highly correlated to mortality (death) risk, there is a large scientific effort to evaluate the effectiveness of various forms of intervention to improve these variables. Motor-cognitive decline is characterized by dementia and immobility, which are not only independent predictors of mortality risk, but large influential factors on perceived quality of life for older adults. It is well established that a consistent aerobic exercise routine will effectively prevent motor-cognitive decline in older adults, but because of its heavy burden, it is not frequently adhered to. Finding other effective practices of improving motor and cognitive function that are more adherable will greatly improve the quality of life for aging individuals and lower their mortality risk.

Realities of Research

Figure 1: Formaldehyde used for preserving endothelial cells

So far, I have found that doing clinical research in a lab is full of excitement and surprises! Beginning at the start of the fellowship, clinical interactions and the IMST study became only two of my many responsibilities. I have been trained on wet lab procedures such as cell collection and isolation, as well as blood processing to assess certain chemicals in the blood. These tasks can be tedious, and are very time and method sensitive. I can spend two hours doing the cell collection and isolation for them to later not give any helpful results when I analyze them. Experiencing frustrating aspects like this is helping me develop the very important skill of patience. I have to use patience in many aspects of my work; wet lab mishaps are not the only issues one can encounter during a typical day of research. I am working in one of the most dynamic physiology labs in the country, with some of the brightest in the field, but despite this we all run into our fair share of hiccups. For example, our huge datasheet for our study got deleted and we spent several days trying to find it. Also, our freezer logging software crashed and left us without decades of logged biological sample information!

Figure 2: Freezing plasma in liquid nitrogen for later analysis

 

 

On the other side of my work, I have to use patience with the clinical subjects. When working with more stubborn older subjects, I find it’s essential to remain patient to maintain professionalism, and to represent our lab in the most positive way possible. I’ve had difficult interpersonal interactions with some of the subjects, but remaining patient and working through issues and questions with them upholds the highest standards of human research we have as an institution. Anyways, our IMST study has (despite some problems) been very on-track and is moving along at a quick pace. We just received more funding from the NIH through a grant that will support us through the next two years of research. Woohoo!

Life of a Scientist

Living as a scientist this summer has been a truly rewarding and educational experience. Going from a very part-time volunteer in the lab doing data entry, to a full-time member of the lab team with much more responsibilities has been an eye-opening transition. I am a much more integral part of the team, and I have to be much more accountable than I was before. I went from only having one task to focus on at a time, to having three-four or more, including clinical visits, grant reviewing, abstract writing, journal club presentations, and reading physiology literature. Balancing and prioritizing my lab tasks is difficult and stressful, and has shown me the less-glamorous side of basic research that you don’t realize until you experience it for yourself. On the other hand, I have been supported in so many ways I never expected, and I love working in a team-based environment. As a non-traditional community college student, I always felt like an outsider and thought I would never be fully accepted into the scientific/academic world. I was proven wrong. Our lab has endless support and an open-door policy when it comes to questions and concerns, which encourages communication. Every member of my lab team has been so helpful in educating me in physiology and research topics I’m unfamiliar with, and has given me all the opportunities I could ask for to be successful at this early stage of my research career. In fact, I should have at least two publications by the end of next year, and probably three by the time I finish my undergraduate studies. This amazing experience has strongly encouraged me to further pursue my career in physiological research.

 

Sources:

DeLucia, C., De Asis, R. and Bailey, E. (2018). Daily inspiratory muscle training lowers blood pressure and vascular resistance in healthy men and women. Experimental Physiology, 103(2), pp.201-211.

Makinzie Hamilton is an undergraduate junior studying Integrative Physiology and Philosophy at the University of Colorado, Boulder. She is working at UCB under Dr. Douglas Seals at the Integrative Physiology of Aging Laboratory, which focuses on improving cardiovascular aging. She is funded through grants from the STRIDE fellowship from the APS and The National Heart and Lung Association (Grant #1 R25 HL115473-01). After graduating in 2020, she hopes to pursue a dual MD/PhD degree and do clinical research regarding infectious disease and tropical medicine. In her free time, she enjoys studying true crime, cooking, painting, and fishing.
February 8th, 2019
Targeting NHE3 in the Hfe mouse model of hemochromatosis

Research Project

Over the summer I have been working in Dr. Bryan Mackenzie’s lab at the University of Cincinnati College of Medicine in the Pharmacology and Systems Physiology department. My focus has been on finding novel therapeutic targets in the treatment and/or prevention of iron overload disorders. Hemochromatosis is just one of several common hereditary disorders that result in iron overload and subsequent liver disease, heart damage, and a slew of other health disorders across several body systems. Since there is no regulated mechanism for iron excretion, iron homeostasis of the body is regulated by iron absorption. The main mechanism by which non-heme iron (the majority of iron humans consume from their diets) is absorbed from the small intestine is the divalent metal ion transporter-1 (DMT1) (3). DMT1 is already a validated therapeutic target in hereditary hemochromatosis. More recently, the Mackenzie lab identified a role for the Na+/H+ exchanger-3 (NHE3) in intestinal absorption of non-heme iron by DMT1.

 

Intestinal iron uptake (redrawn from reference 1)

The Mackenzie lab demonstrated that NHE3 generates the driving force for iron absorption via DMT1 by transporting protons into the small intestine (2). My project this summer has built upon this prior knowledge using an Hfe knockout mouse model. Rendering this single gene inoperative in mice results in a very good model of iron overload. We are then able to test the hypothesis that iron overload in the Hfe KO mouse can be corrected by ablation of NHE3. The idea is that without NHE3, the driving force for DMT1-mediated iron uptake is reduced, thereby reducing iron absorption. If the data supports this hypothesis, we can conclude that ablating NHE3 prevents iron loading in the Hfe mouse model of hereditary hemochromatosis. Even further, we can reveal intestinal NHE3 as a potential therapeutic target in the treatment of iron overload.

Realities of Research

Throughout the summer I have learned countless basic research techniques and have mastered various skills that are good to possess in the Mackenzie Lab. I have learned how to ween and care for our colonies of mice. I now know how to genotype them using tail clippings and polymerase chain reaction (PCR). This step is especially important because it determines which mice are our experimentals, or the mice we collect blood and tissue samples from on experiment days. I was placed in charge of the mouse experiments, learning how to effectively set-up and delegate responsibilities. Being my first full-time experience in a research lab, I appreciated this opportunity to take charge and have ownership over such a large task. I also had the task of running serum iron assays and non-heme iron assays on freezers full of samples that have been collected. This task proved to be challenging and slightly stressful at times, as I found errors in our established assay protocols and analytical procedures. For example, some mice had very little blood collected on experiment days, meaning I had very little serum to run the assays. When the protocols had detrimental errors, I felt I had wasted irreplaceable serum at times. Luckily, I have corrected our protocols and have finally organized/assayed most of our samples. I have also not only learned how to operate a software program called SigmaPlota to analyze my data, but have learned how to edit our labs established transformations within this software. This summer full of learning techniques, troubleshooting, and analyzing my data has been an invaluable experience. I have transformed into a proficient, independent, and productive lab member in just a few months’ time.

Life of a Scientist

I have enjoyed my day-to-day life in the lab this summer. I was pleased to learn that a 9-to-5 workday is certainly possible, with proper planning. I also understood that some late nights/early mornings are unavoidable, especially when things didn’t go as planned and required a little extra time. I discovered that the environment in the lab was much more relaxed than I anticipated. I was able to control my day to day activities with little intervention, unless I needed assistance or extra guidance. This assistance from other lab members is something I really appreciated. Although everyone has their own projects and own experiments to run, a helping hand was always there when I needed it. I liked this collaborative, team-based environment and believe it greatly increased all I was able to learn in the lab this summer. The only con in the life of a scientist that I can think of is the down time that sometimes occurs, as I’m the type of person that likes to stay busy. Luckily, I was able to fill my time by reviewing relevant literature in the field or discussing my progress with other lab members. Overall, I really enjoyed getting to experience the life of a scientist for a summer and look forward to finishing up my project/exploring new directions in the lab.

 

References

  1. Mackenzie B, Garrick MD. Iron Imports. II. Iron uptake at the apical membrane in the intestine. American Journal of Physiology-Gastrointestinal and Liver Physiology289, 2005.
  1. Shawki A, Anthony SR, Nose Y, Engevik MA, Niespodzany EJ, Barrientos T, Öhrvik H, Worrell RT, Thiele DJ, Mackenzie B. Intestinal DMT1 is critical for iron absorption in the mouse but is not required for the absorption of copper or manganese. American Journal of Physiology-Gastrointestinal and Liver Physiology309, 2015.
  1. Shawki A, Engevik MA, Kim RS, Knight PB, Baik RA, Anthony SR, Worrell RT, Shull GE, Mackenzie B. Intestinal brush-border Na /H exchanger-3 drives H -coupled iron absorption in the mouse. American Journal of Physiology-Gastrointestinal and Liver Physiology311, 2016.
Sydney Stone is a junior majoring in Medical Sciences at the University of Cincinnati in Cincinnati, OH. She is a 2018 Short-Term Research Education Program to Increase Diversity in Health-Related Research Fellow (STRIDE) working in Dr. Bryan Mackenzie’s lab at the University of Cincinnati College of Medicine. Her summer of research was supported by APS and a grant from the National Heart, Lung, and Blood Institute (Grant #1 R25 HL115473-01). Upon graduation, Sydney plans to pursue an MD/PhD or MD/MS in order to become a physician scientist. She hopes to combine proficiency in physiology with invaluable access to patients in order to follow her passion for preventing and curing human disease.
February 5th, 2019
Life Behind the Lab Coat: Part 2

Are you curious about the world of science? Do you crave to find new and exciting things about physiology? Well, I do!  Last summer, I had the opportunity to work in a research lab at the University of South Florida Morsani College of Medicine. Furthermore, I was able to renew my APS STRIDE fellowship and continue to work in Drs. Jessica Dominguez Rieg and Timo Rieg’s lab.

Research Project

During my time at the lab, my research project expanded on my work from last summer involving a transporter called the sodium/hydrogen exchanger (NHE). NHE is used to exchange sodium for hydrogen across a cell’s membrane.  There are several different isoforms of NHE; however, my project focused on the isoform NHE3. When NHE3 is genetically deleted from a mouse, called a whole animal knockout, they absorb or reabsorb sodium from the intestine or kidney. Consequently, the NHE3 knockout mice have severe diarrhea, low blood volume, and low blood pressure1. Furthermore, since NHE3 transports hydrogen, it also plays an important role in acid-base regulation. Moreover, NHE3 is also significant for balancing fluid and the regulation of blood pressure.  Last year, my studies concluded that the inducible deletion of NHE3 only in the intestine causes fluid accumulation in the intestine and metabolic acidosis.

This year, my research project remained focused on the role of intestinal versus renal NHE3 and its effects on phosphate homeostasis and blood pressure regulation. Moreover, my research is significant as nothing like this has been done before!  Additionally, there are currently drugs on the market that block NHE3, one example is Tenapanor, which helps to lower blood pressure or high blood phosphate levels; however, the mechanisms of how they work are unclear. As of last year, I saw significant changes in acid-base regulation. Hopefully, this year I will be able to determine how NHE3 affects phosphate homeostasis. Furthermore, I hope I am able to produce more data in order to help answer these ongoing questions about NHE3 and its effects on phosphate homeostasis and blood pressure regulation. Thus far, I have been conducting physiological experiments to determine changes in fluid and food intake, collecting blood and urine for further analysis.  My project is still being conducted but I am excited to see the results!

Life of a Scientist

I love being part of a research lab! Working with people who share the same passion and love discovering new things is amazing! Although I love doing research, the hours can be long. Having to work 8 plus hours a day during the week can be tiring and then having to come in again on the weekends, but I’ll tell you it’s all worth it! One thing I learned is experiments are a process and take time. Last year I thought working in a lab would be similar to being in the labs at the university that were required for your major, but they’re not. Even though they are very different, I still loved every moment I came into work! I am so thankful for this opportunity that APS and my mentors allowed me to expand my knowledge and skills. I am forever grateful for this experience.

 

Citations:

  1. McDonough AA. Mechanisms of proximal tubule sodium transport regulation that link extracellular fluid volume and blood pressure. Am J Physiol Regul Integr Comp Physiol 298: R851–R861, 2010. doi:10.1152/ajpregu.00002.2010.
Alexandria Valdez is a Senior majoring in Biomedical Science and minoring in Psychology at the University of South Florida in Tampa, FL. Alexandria is a 2018 second year Short-Term Research Education Program to Increase Diversity in Health-Related Research (STRIDE) Fellow working in Dr. Jessica Dominguez Rieg and Dr. Timo Rieg’s lab at the University of South Florida Morsani College of Medicine in Tampa, FL. Alexandria’s fellowship is funded by the APS and a grant from the National Heart, Lung and Blood Institute (Grant #1 R25 HL115473-01). Upon graduation, Alexandria wishes to pursue a career in biomedical science as a research scientist.
February 1st, 2019
Take My Breath Away- A Summer of Asthma Research

Research Project

Pathology of asthma.

This summer I had the pleasure of working with Dr. Silveyra and her research team at the Penn State College of Medicine investigating the mechanisms behind adult asthmatic females being more susceptible to air pollution than males. Research has shown that upon exposure to an air pollutant like ozone, females that already have a respiratory disease, such as asthma, are much more likely to develop worsening asthma as well as other respiratory problems. I believe this study is very important in today’s world, where the majority of ozone can be found in cities and industrialized areas that have very high populations. Therefor a female with asthma living in a populated city risks the possibility of her asthma worsening or developing other complications.  When people think of asthma, they usually think of shortness, of breath, trouble breathing, and wheezing. These symptoms are all due to a person’s airways becoming inflamed and an air pollutant like ozone could trigger this. The body expresses proteins called cytokines and when certain types of these cytokines are expressed, they can lead to inflammation like we see in asthma. In recent years a special type of RNA called microRNA (miRNA) has been found to play a key role in regulating the expression of these inflammatory cytokines. My research team and I were particularly interested in miR-712, which is a miRNA known to play a role in regulating inflammatory cytokines. Our idea was that if this miRNA is expressed differently between males and females, this could explain why asthmatic females are more susceptible to air pollutants than males.  This study could lead to the development of treatments specific for males and females.

Realities of Research

This was the first real research project I had ever participated in, so it was pretty intimidating in the beginning. However, as time went on I learned new techniques and began to understand the project and why it was important and that got me really excited to be doing research. The part that surprised me the most is how things that are so small like miRNA can play such a huge part in disease and keeping us healthy. Along the way I had to learn new techniques like how to extract the miRNA’s and how to determine how much was being expressed. In the end the results were a little surprising. Yes, we saw higher levels of miR-712 expressed in asthmatic females that had been exposed to ozone, but we also saw even higher levels of it in asthmatic males that had been exposed to ozone. This may have been due to the fact that male mice typically react quicker to the asthma model we used and that it may take females longer to actually “develop” asthma. I think in the future this model may need to be changed a little bit, but that is all a part of doing research.

Life of a Scientist

I found day-to-day life in the lab to be very exciting. There was always something to be doing and it was nice to know that everything you were doing in a day was for a purpose. One thing that surprised me was how long some procedures can actually take. Procedures I would read about in textbooks always seemed like they were quick and then you have your results, but there is actually a lot of hours that go into some procedures. The worst part was exposing the mice to ozone, because it was a three-hour long exposure and it would get pretty boring. The absolute best part was getting to work with my research team. Every single one of them was so helpful and knowledgeable and I am so grateful for them.

 

Citations

  1. Fuentes, N., Roy, A., Mishra, V., Cabello, N. and Silveyra, P. (2018). Sex-specific microRNA expression networks in an acute mouse model of ozone-induced lung inflammation. Biology of Sex Differences, 9(18).
Ashley Weaver is a rising senior at Penn State University in State College, Pennsylvania majoring in immunology and infectious disease. She is a 2018 Short-Term Research Education Program to Increase Diversity in Health-Related Research (STRIDE) fellow working in Dr. Patricia Silveyra’s lab at the Penn State College of Medicine in Hershey, Pennsylvania. Her fellowship is funded by APS and a grant from the National Heart, Lung, and Blood Institute (Grant #1 R25 HL115473-01). 
After graduating, Ashley plans to pursue a career in clinical lab work for government organizations and then to pursue her masters in immunology.
January 29th, 2019
The Fascinating Relationship Between Inflammation and Respiratory Plasticity

Research Project

I am grateful to say that this summer I had the opportunity to work with Dr. Irene C. Solomon at Stony Brook University, in the Department of Physiology and Biophysics, as an awarded fellow from the American Physiological Society’s Short-Term Research Education Program to Increase Diversity in Health-Related Research (STRIDE) Fellowship. Under the mentorship and guidance of Dr. Solomon, I was able to explore the scientific field of neuroinflammation and the underlying neural mechanisms controlling our central respiratory system.

Figure 1. Intermittent Hypoxia (IH) can induce respiratory motor plasticity, by increasing phrenic motor neuron and diaphragm activity

Acute Intermittent Hypoxia (AIH), also known as the delivery of low levels of oxygen in repetitive bouts, has been demonstrated to alter neural ventilatory control, and therefore, elicit different physiological changes within the respiratory system that can persist into normoxia (also otherwise known as normal O2/CO2/N2 levels).[1] These alterations are more formally known as neural plasticity, which is the nervous system’s response to varying, natural stimuli and/or the initiation and progression of diseases, injuries, and pathology.[2] What that means is that the nervous system attempts to compensate for the lower levels of oxygen by increasing the expression of neurotransmitters like serotonin and adenosine, which then affects the upregulation of specific growth/trophic factors within the Gq and Gs pathways involved in eliciting neural plasticity. More specifically, the G protein coupled receptors (GPCR), serotonin 5HT2 receptors and adenosine A2A receptors, are being targeted within the Gq and Gs, respectively.[3] Although there seems to be some interplay between these two pathways, the Gq pathway and the activation of the serotonin 5HT2 receptors appear to play a larger role in stimulating the physiological changes found during and after AIH.[4] The physiological changes that follow (i.e.increased phrenic motor neuron and diaphragm activity), are utilized within the central respiratory system to essentially breathe “better,” or in other words, consume more oxygen, in such hypoxic conditions.

Additionally, recent evidence from rodent studies, which have implemented different protocols/models for the acute administration of bacterial endotoxin lipopolysaccharide (LPS) — a toxic substance bound to bacterial cell wall, usually causing inflammation in different regions of the brain when

Possible mechanism, including the growth/trophic factor, BDNF, for motor plasticity following AIH in rats and humans

released via bacterium rupture or disintegration[1] — indicates that inflammatory processes can also alter ventilatory control, and subsequently, affect the level of respiratory plasticity that can be achieved. The interactions between LPS-induced inflammation, and accompanying neuroinflammation, and various aspects of ventilatory control, however, are not well understood. It is important to understand how LPS affects the respiratory system since LPS-induced neuroinflammation remains to be a compounding factor of many diseases, such as sepsis, acute lung injury (ALI), and/or acute respiratory distress syndrome (ARDS)[2], and serves as a cause of mortality across a wide variety of respiratory malfunctions (e.g. previously mentioned, OSA). Therefore, the fundamental hypothesis guiding this study is that inflammatory processes can impair multiple aspects of central respiratory neural control, resulting in a reduced ability to adequately and appropriately compensate for disease/pathology. The overall goals of my study are to (1) characterize and quantify the effects (basal ventilatory and respiratory-related neural activities) of moderate (11%O2) AIH in spontaneously breathing male rodents to the 2-hit LPS-induced neuroinflammation model, in which the rats will endure 5 cycles of 3 minutes of 11% O2, 2% CO2, and 87% N2 on and off, and (2) to characterize and quantify the chemical control of breathing via immunohistochemical analyses of various elements from collected tissue samples (e.g. respiratory brainstem cytokines expression, along with neural markers from the Gq pathway). 

Realities of Research

In the beginning of my fellowship, I spent a great deal of my time acquiring new methodological techniques and learning surgical procedures often used in conducting the physiological experiments that are run in lab. Some of the essential skills included establishing EMG signals using tongue and diaphragm electrodes, which is short for electromyography and is an electrodiagnostic medicine technique for evaluating and recording the electrical activity produced by skeletal muscles and the nerve cells that control them (motor neurons)[1], giving intraperitoneal injections (IP), intratracheal injections (IT)., and subcutaneous (sc) injections, conducting femoral and jugular cannulations, administering i.v. drug/saline supplements, and collecting tissue samples that were stored in liquid nitrogen. After acquiring the necessary skills, I was able to spend some time developing a thorough protocol that would help outline the experiments I would be running, and determine what my main hypothesis would be based off of previous findings from the lab and publications I read. I was also given the opportunity to develop my presentation skills as I would prepare and give a presentation on a paper during our bi-weekly lab meetings with the Collins Lab, who we extensively work with, and engage in meaningful conversations on new insights my fellow peers would bring up. I am currently going the data analysis of the rats’ BPM frequency and cyclic height (amplitude) for signs of either an increase or decrease in respiratory motor plasticity post-hypoxia. Immunohistochemical staining of the tissue samples collected will be used to further analyze respiratory brainstem cytokines expression for signs of neuroinflammation and potential decreases in neuroplasticity.

Life of a Scientist

Throughout my experience at the Solomon Lab, I have come to realize that the strange and mysterious world of scientific research is not one of only cut-throat competition and solitude, but a juxtaposition of individualized responsibilities and teamwork. There is something about research that, oddly enough, reminds me of my favorite childhood cartoon show, Scooby Doo. Just like how the Mystery Gang goes around in their fruity van looking for clues to solve the case and figure out the culprit of the crime, a research lab — surprisingly — works in a similar manner. See, being a part of the journey in trying to solve the big mystery is a team effort, unlike the stereotypical image most people conjure up in their minds of an old, crazy gray-haired scientist mixing chemicals together in an underground lab. Just as every member in the Mystery Gang was important to cracking the case, all members in a lab must be willing to cooperate and take on the smaller assignments in order to contribute to the larger picture and find the missing clues to the puzzle. And that’s what I love so much about scientific research: the camaraderie that forms among peers in a lab — sometimes even extending beyond the doors of your very own lab and with the people of the lab across yours. Overall, I am not only grateful for receiving the opportunity to delve deep into the world of physiology and neurobiology research, but also for the opportunity to meet such fantastic people who have helped me grow as a scientist and as an individual.

References

  1. Moya EA and Powell FL. (2018) Serotonin and Adenosine G-protein Coupled Receptor Signaling for Ventilatory Acclimatization to Sustained Hypoxia. Front. Physiol. 9:860. 06 July 2018. DOI: 10.3389/fphys.2018.00860
  2. Fuller, D. D., & Mitchell, G. S. (2017, January). Respiratory neuroplasticity – Overview, significance and future directions. DOI: 10.1016/j.expneurol.2016.05.022. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/27208699
  3. Figure 1. Dale, E. A., Mabrouk, F. B., & Mitchell, G. S. (2014, January 29). Unexpected Benefits of Intermittent Hypoxia: Enhanced Respiratory and Nonrespiratory Motor Function. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4073945/figure/F3/
  4. Figure 2. Dale, E. A., Mabrouk, F. B., & Mitchell, G. S. (2014, January 29). Unexpected Benefits of Intermittent Hypoxia: Enhanced Respiratory and Nonrespiratory Motor Function. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4073945/figure/F5/
  5. Moya EA and Powell FL. (2018) Serotonin and Adenosine G-protein Coupled Receptor Signaling for Ventilatory Acclimatization to Sustained Hypoxia. Front. Physiol. 9:860. 06 July 2018. DOI: 10.3389/fphys.2018.00860
  6.  Moya EA and Powell FL. (2018) Serotonin and Adenosine G-protein Coupled Receptor Signaling for Ventilatory Acclimatization to Sustained Hypoxia. Front. Physiol. 9:860. 06 July 2018. DOI: 10.3389/fphys.2018.00860
  7. Britannica, T. E. (2014, November 18). Endotoxin. Retrieved from https://www.britannica.com/science/endotoxin
  8. Hong Chen, Chunxue Bai & Xiangdong Wang (2010). The value of the lipopolysaccharide-induced acute lung injury model in respiratory medicine. Expert Review of Respiratory Medicine, 4:6, 773-783, DOI: 10.1586/ers.10.71
  9.  Electromyography (EMG). (2018, May 05). Retrieved from https://www.mayoclinic.org/tests-procedures/emg/about/pac-20393913

Rashi Bhatt is a sophomore majoring in Computational Neuroscience and Public Health, with a minor in Computational Medicine at Johns Hopkins University in Baltimore, MD. She is a Short-Term Research Education Program to Increase Diversity in Health-Related Research (STRIDE) Fellowship working in Dr. Irene C. Solomon’s lab at Stony Brook University in Stony Brook, NY. Rashi’s fellowship was funded by the APS and a grant from the National Heart, Lung and Blood Institute (Grant #1 R25 HL115473-01). After graduation, she plans on attending Johns Hopkins Bloomberg School of Public Health to receive her MPH and hopefully go on to attend medical school, and specialize in neurosurgery and neuro-imaging.