Thank Cod: There’s Something Fishy about the Brain-Gut Connection to Amyloids
We are continuing with our Neuroscience theme and so this week we are taking a look at two interesting studies out about Parkinson’s Disease (PD). Parkinson’s Disease is a movement disorder that affects nearly one million people in the United States alone. Lewy bodies, aggregates of the protein α-synuclein, are a hallmark of the disease. 1 First up is a study that looks at the effects of acrolein on α-synuclein formation. Acrolein, or 2-propenal, is a byproduct of cooked foods, is found in tobacco products, and is a product of the combustion of petroleum and biodiesel fuels.2 Not only is acrolein exposure implicated in PD, it has also been implicated in other chronic illnesses, such as cancer, smoking-related illnesses, multiple sclerosis, diabetes, to name a few. Abeje Ambaw and colleagues, of Purdue University, recently looked at the mediative effects of acrolein on α-synuclein formation and neuronal cell death. Acrolein causes covalent protein modifications of the nucleophilic side chains of lysine, histidine, and cysteine. The study was able to demonstrate that acrolein may be a critical mediator in cellular and animal models, both in vitro and in vivo. In mice injected with acrolein, an increase in α-synuclein aggregation occurred as well as an increase in motor deficits. They also discovered that the addition of hydralazine, an acrolein scavenger and a vasodilator, reversed the motor-deficits.3
The next study was led by Tony Werner of the Chalmers University of Technology in Sweden. The team looked at the gut-brain connection to PD. It is suspected that PD “may originate from the gut via the enteric nerve system”, where α-synuclein is expressed in cells in the gut epithelium. Food allergens may adopt an amyloid state in order to pass through the gastrointestinal tract. In fish, β-parvalbumins (PV) play a role as the major allergen in fish hypersensitive individuals. In the absence of Calcium ions, PV aggregates and forms amyloids within a few hours. Furthermore, PV can interact with α-synuclein and was found to block α-synuclein aggregation in vitro. PV is found in all species of fish, with the largest prevalence in cod, carp, redfish, and herring. The team found that PV amyloids scavenge α-synuclein monomers and inhibit aggregation.4 Since α-synuclein aggregation is suspected cause of PD, consuming fishes rich in PV may be a possible preventative measure, given you do not have a PV allergy.
- What is Parkinson’s Disease? (n.d.). In Parkinson’s Disease Foundation. Retrieved on May 11, 2018 from http://parkinson.org/understanding-parkinsons/what-is-parkinsons
- J.F. Stevens & C.S. Maier, Mol Nutr Food Res., 52(1), 7 (2008).
- A. Ambaw et al., Mol Cell Neurosci., 88, 70 (2018).
- T. Werner et al., Nature Scientific Reports, 8, 5465 (2018).