The Effect of an Antioxidant Supplement on a Mouse Model of Alzheimer’s Disease

Student: Jennifer Grossmann
Major: Cognitive Behavioral Neuroscience
Advisors: Dr. Amy Jo Stavnezer, Dr. Susan Clayton

Alzheimer’s Disease (AD) is a neurodegenerative disorder that causes abnormal cellular processes in the brain leading to behavioral changes such as progressive memory loss, reduced inhibition, and decreased motor functions. Previous research has explored treatment options such as behavioral therapies or altered diets. The current study aims to determine the effectiveness of an over-the-counter antioxidant supplement on AD in a mouse model. It was hypothesized that supplementation to mice genetically manipulated to show AD would improve their learning and memory in standard rodent behavioral tests. Unfortunately, there was no significant effects of the antioxidant supplement in this study. Although it was not found to induce changes in the behavior of the mice, perhaps adjustments in the length of time or start time of supplementation could result in the positive effects in mice that could then be used in humans with AD.

Description

Alzheimer’s Disease (AD) affects approximately 5.8 million people in the United States alone, and deaths from the disease increased 145% from 2000 to 2017 (Alzheimer’s Association). Based on current trends, there are projected to be about 89 million people over the age of 65 in the US alone by 2050. The disease is biologically characterized by a buildup of amyloid‐β proteins and tau tangles which form plaques in the brain and disturbs proper functioning (Fuhrmann et al., 2010; Herman et al., 2019). These changes in the brain result in cognitive deficits such as incremental memory loss, confusion, disorientation, or wandering (Logsdon et al., 1998).

Dietary supplements have shown great promise as a form of treatment for AD. Specifically, supplement of antioxidants combat oxidative stress and reduce chronic inflammation, both of which plague those with AD.  An over-the-counter dietary supplement comprised of five herbal ingredients including silymarin from milk thistle (Silibum marianum), bacopa extract (Bacopa monniera), ashwagandha (Withania somnifera), green tea extract (Camilia sinesis), and curcumin from turmeric (Curcuma longa) was tested in this experiment.  It has been shown to produce beneficial effects of antioxidants such as reducing oxidative stress, by means of increasing antioxidant enzyme expression.

Currently, no published research has investigated the direct impact of this supplement on AD in a mouse model. The following study explores the potential preventative effects of the phytochemical mixture on a mouse model of AD.  Learning, memory, and anxiolytic behaviors were tested with a standard spatial learning task, the Morris water maze, and an activity and anxiety test, the open field.

Though all groups did show the ability to learn and store spatial memories in the Morris water maze, there was no benefit of the dietary supplement. It is possible this antioxidant does not interact with mouse cells in the exact way that was theorized or needs to be supplemented at a different dose range. There is still a potential for antioxidant supplements to improve deficits due to Alzheimer’s Disease, for instance the Mediterranean diet, which is full of natural antioxidants seems promising, and perhaps a different dietary supplement could produce positive results.

Jennifer will be online to field comments on May 8:
10am-noon EDT (Asia: late evening, PST 6am-8am, Africa/Europe: late afternoon)

53 thoughts on “The Effect of an Antioxidant Supplement on a Mouse Model of Alzheimer’s Disease”

  1. Obviously AD is a growing problem and while it effects me personally I am curious what drew you to this topic and would it be something you would continue to research after I.S.?

    1. Alzheimer’s Disease has affected my family as well and always fascinated me. The fact that so little is known about it also drew me to the topic, knowing that I could help the field in some way.

  2. Great work Jennifer! Your work further indicates that we still have so much to learn and study about Alzheimer’s Disease. If you were to conduct your research again, what you would do differently?

    1. Thank you! For future studies of the relationship between antioxidants and AD, I would like to see whether giving the mice the supplement earlier in their life, or for a longer period of time, could cause a significant impact. Additionally, giving the rodents an antioxidant-rich diet reflecting more of what they would eat in nature compared to just supplementing their diet could be interesting.

  3. Hey Jenny. Hope you’re well. Thanks for leading and for sharing. Great stuff about AD. Would it be possible to look at AD on the other end and test preventative measures? Can we work to overcome genetics and lifestyle habits to reduce the onset of AD? You’re a rock-star. Stay strong and hope to connect soon. Coach Zidron

    1. Hi Coach Zidron! Thank you for looking at my research. The idea of antioxidant supplementation was supposed to be a preventative measure, and if not then I hoped it would slow the progression of the disease. There are certainly habits that have shown benefits when preventing or slowing the onset of AD such as exercise, antioxidant-rich diets like the Mediterranean Diet, and positive sleep habits.

  4. Good morning Jenny – thanks for sharing your research today! With all of the reading you did about the benefits of antioxidants, did you change your diet or habits? What are the best Lowry hacks that can help college students load up on healthful meals?

    1. Hi Dr. Stavnezer, thank you for the questions! There was one particular study which reported the benefits of walnuts on memory and learning in mice. After reading that article I definitely started eating more walnuts in Lowry, hoping to feel similar results. I think balance is the most important thing, especially in a dining hall with so many options. It’s important to think about what kinds of foods will help you feel best after you’ve eaten them while also choosing foods that you want to eat!

  5. Great job Jennifer,
    Alzheimer’s Disease is still a growing problem, and needs addressed.
    I hope you plan to continue more research on this topic.

    1. Thank you so much for your interest. I hope to be involved in projects like these in the future, there is still so much to learn!

  6. Thank you for sharing your research. The other comments had great questions and I look forward to reading your responses to them. Good luck on your next steps and congratulations on graduation.

  7. Jenny,
    There’s likely no disease more urgently needing research like yours. Thank you!

    A few questions : (Really, just food for thought. Don’t feel compelled to respond)

    Are there any known limitations of the mouse model of AD for predicting results in humans? Have there been experimental results from other investigational interventions that suggest either human-murine similarities or specie differences that generally make the mouse model a good one or a poor one for pre-clinical investigations?

    Of the 89 million people over the age of 65 in the US alone by 2050, based on current prevalence of 5.8 million in the over 65 population, today, what will be the projected disease burden in 2050, if effective preventions/treatment are not found? What will the annual economic costs be in medical care, and lost employment by care givers? Would focusing on the potentially avoidably costs of AD help secure more funding? How much savings later could be expect for each extra dollar spent now on AD research?

    Since Turmeric is so widely used in the Indian diet, it was of note a few years ago when epidemiological studies suggested a significantly lower prevalence of AD in India, than in the West. At the same time, others suggested the apparent lower incidence was related to insufficient survey methodology, failure to control for age, etc. What have you heard about AD in India, and a possible impact of the Indian use of turmeric?

    In the US, dietary turmeric is sometimes formulated with extract of black pepper, which is said to dramatically increase bioavailability of the other-wise poorly absorbed turmeric. Any thoughts?

    Could you point me to any epidemiological work suggesting the impact of the Mediterranean Diet on AD?

    Since there is evidence suggesting physical exercise may be beneficial in AD, are you aware of any studies in which the experimental design was to compare sedentary mice with active mice?

    1. Hi Dan,
      This is Jenny’s advisor, Amy Jo. Jenny is perfectly capable of answer, but your questions were really interesting to me, so I did a quick search – I can’t find much updated info on incidence of AD in India, but you are correct that there are certainly parts of the world where turmeric consumption could lead to some interesting epidemiological work. I do have a few links to share on the Mediterranean diet – this Scientific American piece is one we read in my Behavioral Neuroscience class: https://www.scientificamerican.com/article/a-rare-success-against-alzheimer-rsquo-s/
      and here are a few links for empirical or review papers as well: Mediterranean diet, cognitive function, and dementia: a systematic review. I Lourida, M Soni, J Thompson-Coon, N Purandare… – Epidemiology, 2013, Vol. 24, No. 4;
      Gotsis, E., Anagnostis, P., Mariolis, A., Vlachou, A., Katsiki, N., & Karagiannis, A. (2015). Health Benefits of the Mediterranean Diet: An Update of Research Over the Last 5 Years. Angiology, 66(4), 304–318;
      Mediterranean Diet and Risk for Alzheimer’sDiseaseNikolaos Scarmeas, MD,1–3Yaakov Stern, PhD,1–3Ming-Xin Tang, PhD,1,4Richard Mayeux, MD,1–3and Jose A. Luchsinger, Annals of Neurology Vol 59 No 6 June 2006.

  8. Jenny, CONGRATULATIONS!
    You have SO much to be proud of!!! Sending you best wishes. XO

  9. JENNY,

    Hi Jenny :)) Congrats on finishing your IS!! You’re amazing!!! I know you worked very hard and I bet it feels great to be done!!

    Alzheimer’s has also affected my family and so this topic is important to me. My question is, do you think testing on a different animal would have shown more clear results? Also, do you think if you had more time that the mice would’ve responded more?

    1. Hi Rachel, thank you for your interest! It is possible the specific antioxidant supplement we used did not produce significant results because mice were the test subject. A previous IS student who used rats instead of mice found this supplement to induce significant changes to their memory. Those findings could indicate that this antioxidant mixture could have varying effects on different species.

      I do think that a longer time span would have allowed the disease to progress further in the animals which likely would have resulted in a greater difference between those mice and the mice without the genetic predisposition for the disease. Given that there is still so much unknown about the supplement, it is hard to know if time alone would have lead to results that supported my original hypothesis.

  10. Hi Jennifer,

    Antioxidants have really seemed to be the new thing on the market and labeling.
    I have a few questions that I wanted to have your insight on.

    1. Antioxidants seem to be pushed out so much lately (food, medicine, science, etc) for the prevention of many diseases (including AD). Have you bumped into any research suggesting the possible negative effects of too much antioxidants?
    2. Is there any difference (chemically/structurally/mechanism of actions) between the antioxidants from food compared to OTC?
    3. Are antioxidants only from the food and medicine we ingest? Can they be produced by the body and things we do everyday (exercising, sleeping, meditation, etc)?

    Thank you for your presentation and congratulations.

    1. Hi Brian, thank you for your interest.

      1. I didn’t find any prominent research that described negative side effects, which is another reason this avenue of prevention for AD is so appealing. I would assume there no benefit of overloading with antioxidants, and much like all processes in the body, a balance is needed for normal functioning.
      2. As far as the chemical difference between antioxidants from food compared to over-the-counter supplements, there are not many that I am aware of. The supplements are typically a combination of different foods or extracts of foods, meaning there are no huge differences in chemical structure. The main difference is that supplements are a collection of these antioxidants instead of just one source from a particular food.
      3. Antioxidants are produced naturally in our bodies, which are supplemented by the foods and medicines we ingest. I am not aware if behaviors such as sleep and exercise can increase internal antioxidant production, but negative habits can cause the processes that produce them to suffer.

  11. Hi Jenny,

    Nice work! Your experiments and presentation are really impressive. My question is in regards to your Cont-Tg group. Did you expect those animals to be different from the others in either open-field and/or water maze behavior, and do you have any thoughts about why they did not show “deficits?”

    Thanks and congratulations!

    1. Hi Doug, interesting insight. I did hypothesize that the mice without supplementation (control) and with AD (transgenic or tg) would perform significantly worse in the learning and memory tests as they should have endured the most negative effects of the disease without rescue. Despite that, the data showed no significant difference which could have been due to the small sample size or the short time span of the study. In most other cases I would expect to see this group have the most significant difference.

  12. So proud of you Jenny. Great job. Wish I could have made you explain this poster in real life.

    Coach

  13. Great work, JG! I’m so proud of all that you’ve accomplished! Congrats!

    Do you know if there are lower levels of AD found among those who consume antioxidant rich diets? Such as in the Mediterranean region?

    1. Thanks Harvey! Good question, my advisor’s response above to Dan’s questions may shed some light. Although there may not be epidemiological studies that show this to be true, controlled studies that have shown the positive effects of the Mediterranean diet are evidence that AD may be reduced in regions where this diet is prominent.

  14. Hi JJ! Fascinating project. Congrats! So proud of all of the work that you have done and so excited to see what’s to come. You deserve all of the best. Keep up the hard work.

  15. HI Jenny!
    I’m so proud of all you’ve done for IS and in all the other ways you’ve excelled at The College. We’ve known each other since you started at Wooster, way back when we went to the Nursery School and studied trauma in children and ways to ameliorate it. Now you’ve “spanned the lifespan” and are trying to help older adults. I wish you all success in whatever comes next!
    Now I better go make a big salad with plenty of antioxidants in it!!!!!!!
    Thanks for your hard work and amazing attitude as a student and scientist!

    1. Hi Dr. Thompon, thank you for your response! Your FYS class set me on this path and helped me hone my passion for neuroscience. Hope you are well, enjoy your salad!

  16. Hi, Jennifer!

    Your work is very interesting, and your poster is very clear! Nicely done!

    I was curious if you could elaborate on the molecular mechanism of action of Protandim? I’m wondering if it provides benefits to the mice in other ways that could mitigate the onset or symptoms of AD.

    Could you explain the AD mouse model a little more? Is the onset of AD gradual in these mice, or do they exhibit symptoms fairly early in their life? Is is possible with this model to test Protandim as a preventative measure vs. as a treatment after onset?

    1. Hi Lexie, thank for your interest. Based on previous research, I hypothesized that Protandim activated a pathway involving a transcription factor called Nrf-2 (NF-E2-related factor 2) which has been found to be integral in indigenous antioxidant production. Antioxidants help to reduce oxidative stress which is increased in individuals with AD and negatively affects the body’s cells. Because of this ability, Protandim was expected to reduce oxidative stress in the mice which would have slowed the progression of the disease in their brains.

      In this mouse model, plaques in the brain that form because of AD are found by 3 months old, and significant memory and learning deficits are usually prevalent by 4-6 months of age. I started giving the mice the antioxidant supplement at 3 weeks old for about 6 months because of this known timeline. This was meant to prevent the disease onset before it began, and if not then the goal was to slow the progression before that 3-month mark.

  17. Jenny Jenny! Fascinating research! Thanks so much for going there and presenting your findings so concisely.

  18. Look at how SMART and INCREDIBLE my beautiful roommate is!! It was an honor and joy to watch you complete this project this past year. I appreciate your willingness and patience in explaining all of these scientific words to me. I love you JenJen!!

  19. Excellent work, Jenny! Thank you for sharing it here. (I always love a good graph with error bars.)

  20. Hi Jenny! I know you’re done answering questions but I just wanted to say I am super proud of you and miss hanging out in our IS carrel together!

    1. Thanks Rebecca, I miss our IS writing times together too! Strong work on all you accomplished!

  21. Good work. Thanks for your presentation. We eat pecans at our house. I hope they work as well as walnuts.

  22. Jenny!! Wow this is such impressive stuff and I am so glad that I got to hear about your research process along the way. Miss you and your smart, funny brain!

  23. Congrats on all of your hard work and finishing a great project! I learned a lot about AD! I can’t wait to see all of the amazing things you’re going to do!

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