This post is by associate Triage Practitioner, and guest blogger, Matthew Savage
Awareness of the pathological consequences of traumatic brain injury has increased dramatically over the last few years, with huge concern over repeat injuries and their link to dementia diagnosis and neurodegeneration. For example, heading a football has been called into question following dementia diagnoses and death amongst the England World Cup winning team of 1966. But moderate and severe traumatic brain injuries (TBI) are an even bigger concern, with these injuries contributing to the highest figures of death and disability in the under 40s age range (Lawrence, 2016). Limited treatments exist for TBI but omega-3 fatty acids are providing promising results as a putative treatment for traumatic brain injuries.
What is Traumatic Brain Injury?
A Traumatic brain injury (TBI) can be defined as an alteration to normal brain function, caused by an external force such as a jolt, blow or collision (Menon, 2010) and this can lead to a cascade of pathological consequences, from reduced blood flow to the brain, chronic inflammation, underutilization of energy, direct axonal damage and cell death. TBI can be associated with significant cognitive impairments including attention deficits, memory problems and difficulties associated with problem solving. Whilst we have a relatively good understanding of the physical damage and symptoms of TBI, effective treatments are still lacking. There is some suggestion that pharmacological treatments (Dougall, Poole & Agrawal, 2015), acupuncture (Wong, Cheuk, Lee & Chu, 2013) or rehabilitation my lead to improvements for TBI sufferers but a lack of high-quality evidence means the treatment search continues. Promising findings exist suggesting omega-3 fatty acids may help to reduce inflammation and also provide neuroprotective qualities for the brain.
What are the different types of Omega-3?
Long chair polyunsaturated fatty acids (PUFAs) are essential for normal brain development and function. The main PUFAs are Docosahexaenoic acid (DHA), Eicosapentaenoic acid (EPA) and Alpha-linolenic acid (ALA). Two omega-3 fatty acids have shown promising laboratory evidence for neurogenesis and neuron repair in patients with TBI (Hasadsri et al, 2013) and these are DHA and EPA. We can increase our intake by eating more oily fish, vegetables and through supplementation with fish oils, cod liver oil and other vegan alternatives.
How are Omega-3 PUFAs useful to reduce the damage caused by TBI?
Omega-3 fatty acids can help protect the brain before, during and after injury by:
Reducing inflammation – Recent evidence suggests that Omega-3 fatty acids can contribute to a reduction in pro-inflammatory release by altering the fatty acid composition of cells and cytokines (cells which can increase or decrease inflammation) involved in inflammatory response (Calder, 2010). Both EPA and DHA have been shown to decrease the secretion of inflammatory cytokines in vitro and animal studies (Gutierrez et al, 2019) and this process prevents inflammation from turning into excessive chronic inflammation, something which causes further damage to our brain cells by reducing blood floor and oxygen supply. These mechanisms indicate the importance of further research in omega-3 fatty acids as preventative measures, as changing fatty acid composition of cells can be done by encouraging supplementation as a preventative measure and also following injury.
Reducing cardiovascular damage – When the brain is injured, the blood supply can be affected, as well as oxygen supply. It is vital our brains receive blood full of oxygen and this supply is regulated by the blood brain barrier (BBB), a barrier which allows only certain things into our brain. The BBB is made up of endothelial cells, and through clinical trials Omega-3 fatty acid supplementation has been shown to improve endothelial function in a number of diseases (Felau et al, 2018). DHA is quantitatively the most important Omega-3 PUFA and diffuses into the brain via the BBB, helping to protect the barrier before, during and following injury and thus, reducing cardiovascular events which can occur if damage to the BBB is severe.
Keeping the brain in balance - It has been reported that Omega-3 fatty acids are “effectively natural agents in reducing the neuronal damage and reducing oxidative stress in the brain” (Kumar et al, 2014). Oxidative stress is essentially an imbalance between antioxidants and free radicals in the brain and body which can cause chronic inflammation. This imbalance can lead to a number of chronic illnesses and can also cause problems with energy uptake in the brain. No energy means our brain cells will die. Animal studies have shown it is possible to reverse declines in receptors capable of metabolising glutamate, one of the brains most important neurotransmitters, by supplementing the rats with Omega-3. By ensuring this neurotransmitter is protected, we can reduce cell death which can occur if glutamate cannot be metabolised.
Support brain membrane development – Many animal studies support the correlation between a direct role of DHA in neurogenesis, synaptogenesis, and myelination, as well as developing memory and continued normal memory function throughout life (Joffre et al, 2014; Yurko-Mauro et al, 2015). Following injury, Omega-3 fatty acids are necessary for the repair of brain cells and for the communication that takes place between them through supporting healthy growth and repair of myelin, the cell membrane which speeds up signals as they travel down our neurons.
Conclusion
For the future, Omega-3 fatty acids have shown much promise as a putative treatment for traumatic brain injury. It is vital that studies consider all of the examined mechanisms in the development of Omega-3 fatty acid interventions. The development of novel treatments following a traumatic brain injury should look to minimize the cascade effect by modifying the inflammatory response and not eliminating it completely as this has been shown to be detrimental to recovery. It is this fine balance that must be struck, as well as considering dosage implications, specificity of target intervention and proving behavioural and psychological benefits of omega-3 supplementation to make them justifiable for clinical trial.
About Matt Savage
Matthew Savage is an associate Triage Practitioner, has an MSc in Psychology, is a qualified personal trainer, and has worked within the field of cognitive rehabilitation for 5 years. He is an FA qualified football coach, with a keen interest in moral behaviour and wellbeing within team sports.
References
Dyall S. C. (2015). Long-chain omega-3 fatty acids and the brain: a review of the independent and shared effects of EPA, DPA and DHA. Frontiers in aging neuroscience, 7, 52. Doi: https://doi.org/10.3389/fnagi.2015.00052
Dougall, D., Poole, N., & Agrawal, N. (2015). Pharmacological for chronic cognitive impairment in traumatic brain injury. Cochrane Database of Systematic Reviews, 12(1). Doi: 10.1002/14651858.CD009221.pub2.
Ramos Cejudo, J., Wisniewski, T., Marmar , C., Zetterberg, H., Blennow , K., de Leon, M. J., & Fossati , S. (2018) Traumatic Brain Injury and Alzheimer's Disease: The Cerebrovascular Link, EBioMedicine 28, pp. 21 30. doi : https://doi.org/10.1016/j.ebiom.2018.01.021
Wong, V., Cheuk, D.K.L., Lee, S. & Chu, V. (2013). Acupuncture for acute management and rehabilitation of traumatic brain injury.Cochrane Database of Systematic Reviews, 3(1).