How Inflammation Works: Neurological Conditions

TITLE: How Inflammation Works: Neurological Conditions

AUTHOR: Eleanor Good (Student Nutritionist)

Inflammation in the nervous system, often referred to as neuroinflammation, can be harmful especially when it occurs over a prolonged period of time¹. While inflammation itself does not necessarily cause disease, it does contribute to disease pathogenesis (development) both across the peripheral and central nervous systems.

Examples of inflammatory conditions in the peripheral nervous system includes neuropathic pain and fibromyalgia.

Examples of inflammatory conditions in the central nervous system includes Alzheimer’s Disease, Parkinson’s Disease, anxiety and depression

The role of inflammation in common neurological conditions

Fibromyalgia is a disorder characterised by widespread musculoskeletal pain accompanied by fatigue, sleep, memory and mood issues. Researchers believe that fibromyalgia amplifies painful sensations by affecting the way your brain processes pain signals. It is thought that microglia cells; cells that are among the most numerous in the brain, are responsible for the inflammation characteristic in this disease². Microglia cells secrete pro-inflammatory molecules called cytokines which triggers an inflammatory state that suppresses the secretion of dopamine – a chemical that is responsible for transmitting signals between the nerve cells of the brain.

Alzheimer's disease is a progressive form of dementia that interferes with memory, thinking, and behaviour. The progressive decline in cognition observed in Alzheimer's disease is historically attributed to two things; the build-up of plaques and neurofibrillary tangles in the brain^3-5. More recently, a third factor has come into light, that being prolonged inflammation of the brain’s microglia cells. It is believed that this neuroinflammation, in conjunction with the plaques and neurofibrillary tangles between neurons destroy the messages in the brain which impact thinking, behaviour and memory^3-5.

Depression is a mood disorder that causes a persistent feeling of sadness and loss of interest. Also called major depressive disorder or clinical depression, it affects how you feel, think and behave and can lead to a variety of emotional and physical problems. While many factors play a role in the development of depression, this condition has been associated with increased activation of the immune system which triggers an inflammatory response that disrupts the processes in the brain that help regulate our mood⁶.

Does what we eat effect the health of our brain?

While we cannot control all factors that influence our health, there are several lifestyle behaviours over which we have a bit more say, such as our diets, that influence levels of inflammation in the body. 

There are many nutrients that are particularly good at reducing inflammation in our bodies. They include fruits (such as berries), vegetables (such as broccoli, spinach and kale), herbs (such as green tea), spices (such as turmeric), wholegrains, legumes, and omega-3 fats found in foods such as fish and extra virgin olive oil. These foods are rich in fibre, antioxidants and polyphenols, all of which have anti-inflammatory properties.

These aforementioned foods are featured in abundance in a Mediterranean diet. The Mediterranean diet is one of the world’s most well researched diets for its anti-inflammatory and health promoting effects.

To learn more about the role of inflammation in different endocrine conditions, continue reading our series by student nutritionist Eleanor Good, How Inflammation Works: Endocrine Conditions

To skip the rest of the series and instead learn how to fight inflammation with food, read our article from Registered Dietitian, Andy de Santis, on the foods he recommends to combat inflammation.

The information provided in this article is intended for educational purposes only and is general advice. It should not, nor is it intended to be, relied on as a substitute for individual medical advice or care. If the contents of this, or any other of the blogs in this series raises any concerns or questions regarding your health, please consult a qualified healthcare practitioner.

References

1. https://www.frontiersin.org/articles/10.3389/fncel.2018.00072/full
2. Younger J. Microglia: New targets in the treatment of fibromyalgia. Presented at: Congress of Clinical Rheumatology; May 17-20, 2018; Destin, Fla.
3. Heneka, M. T., Carson, M. J., El Khoury, J., Landreth, G. E., Brosseron, F., Feinstein, D. L., Jacobs, A. H., Wyss-Coray, T., Vitorica, J., Ransohoff, R. M., Herrup, K., Frautschy, S. A., Finsen, B., Brown, G. C., Verkhratsky, A., Yamanaka, K., Koistinaho, J., Latz, E., Halle, A., Petzold, G. C., … Kummer, M. P. (2015). Neuroinflammation in Alzheimer's disease. The Lancet. Neurology, 14(4), 388–405. https://doi.org/10.1016/S1474-4422(15)70016-5
4. Kinney, J. W., Bemiller, S. M., Murtishaw, A. S., Leisgang, A. M., Salazar, A. M., & Lamb, B. T. (2018). Inflammation as a central mechanism in Alzheimer's disease. Alzheimer's & dementia (New York, N. Y.), 4, 575–590. https://doi.org/10.1016/j.trci.2018.06.014
5. Miller, A. H., & Raison, C. L. (2016). The role of inflammation in depression: from evolutionary imperative to modern treatment target. Nature reviews. Immunology, 16(1), 22–34. https://doi.org/10.1038/nri.2015.5
6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6658985/