Unveiling the Link Between Fatty Acids and Neurodegenerative Diseases

Long-chain polyunsaturated fatty acids (LCPUFAs) have an unexpected impact on insulin, revealing more about the relationship between LCPUFAs and neurodegenerative diseases, according to a recent study published in ACS Chemical Neuroscience (1).

Lead author Dmitry Kurouski, a professor in the Texas A&M College of Agriculture and Life Sciences Department of Biochemistry and Biophysics, said consumer perception drives people to cater their diets to include foods that contain LCPUFAs such as DHA and ARA.

LCPUFAs, including docosahexaenoic acid (DHA) and arachidonic acid (ARA), are known to support cognitive function, mood regulation, and circulatory health (1). Foods that are rich in these fatty acids are preferred by consumers because of their health benefits, he said in an interview with AgriLife Today, Texas A&M University’s digital magazine. These foods come from aquatic sources, animal sources, plant sources, and even fruits and seeds (3).

Human Insulin Vials | Image Credit: © Sherry Young - stock.adobe.com

“Most of us think of these fats as good or healthy, and, for many people, they are,” Kurouski said (2). “However, we found that these polyunsaturated fatty acids can do a very unexpected thing when they interact with insulin. And this is not just true for one or two of these fatty acids, but a large group of them.”

In a most recent study, Kurouski and his team examined the potential relationship between LCPUFAs and neurodegenerative diseases like diabetes type 2 and Parkinson's disease. They sought to figure out whether the presence or absence of LCPUFAs in one’s diet had a direct correlation to the likelihood of them being afflicted with a neurodegenerative disease. Using atomic force microscopy to learn what LCPUFAs alter insulin aggregates, Kurouski and his team then investigated the structures of insulin fibrils using infrared (IR) spectroscopy and circular dichroism (CD) (1).

What the research team found was that LCPUFAs did have an impact. The team discovered that LCPUFAs can accelerate the aggregation between insulin and α-synuclein proteins (1). This is significant because both insulin and α-synuclein proteins are implicated in diabetes type 2 and Parkinson's disease, respectively (1). The human metabolism requires the insulin protein. Any potential defects in insulin can lead to health problems such as diabetes (2).

The research team investigated the influence of 10 different LCPUFAs and LCUFAs on insulin aggregation (1). All analyzed fatty acids significantly accelerated insulin aggregation. Furthermore, the study found that protein aggregates formed in the presence of these fatty acids exhibited significantly higher cellular toxicity compared to insulin fibrils grown in a lipid-free environment (1).

However, Kurouski also noted that while the findings in their study are important, more research is needed to fully understand how LCUFAs directly impact the human body, especially when it comes to neurology.

“This is fundamental research that requires more investigation,” Kurouski said to AgriLife Today (2). “What this work shows is that the picture is more complex, nutrition is complex, and we shouldn’t treat anything as black and white, universally healthy or unhealthy.”

Understanding the molecular mechanisms behind neurodegenerative diseases is essential for developing effective treatments. By uncovering the link between LCPUFAs and protein aggregation, this research opens new avenues for therapeutic interventions targeting these pathways (1).

References

(1) Hoover, Z.; Lynn, M.; Zhaliazka, K.; et al. Long-Chain Polyunsaturated Fatty Acids Accelerate the Rate of Insulin Aggregation and Enhance Toxicity of Insulin Aggregates. ACS Chem. Neurosci. 2024, 15 (1), 147–154. DOI: 10.1021/acschemneuro.3c00583

(2) Vargo, A. Researchers find unexpected link between essential fats and insulin aggregation. AgriLife Today. Available at: https://agrilifetoday.tamu.edu/2024/05/02/researchers-find-unexpected-link-between-certain-fatty-acids-and-insulin-aggregation/ (accessed 2024-05-03)

(3) Abedi, E.; Sahari, M. A. Long-chain Polyunsaturated Fatty Acid Sources and Evaluation of their Nutritional and Functional Properties. Food Sci. Nutr. 2014, 2 (5), 443–463. DOI: 10.1002/fsn3.121