• Administering krill oil to PD worm model preserves neurons associated with cognition and reduces the accumulation of the deleterious ⍺-synuclein protein.
  • Krill oil-treated PD worms display reprogrammed gene activity that attenuates hallmarks of aging like harmful, reactive oxygen-containing molecule buildup — oxidative stress.
  • Krill oil-treated worms exhibit improved cognitive function and a diminished predicted age as gauged by an aging calculator.

Research suggests that oil secreted by small ocean-dwelling crustaceans called krill protects against brain inflammation, and its dietary benefits may exceed those of fish oil. Like fish oil, krill oil contains long-chain omega-3 fatty acids. However, krill omega-3s are attached to molecules that maintain the structural integrity of brain cells called phospholipids. The attributes that distinguish krill from fish oil warrant further exploration of krill oil’s benefits to brain health and possible capabilities to impede age-related cognitive decline.

Published in Aging, Nilsen and colleagues from the University of Oslo in Norway examined how lipid extracts from Antarctic krill attenuate age-related cognitive decline in a PD model of roundworm. They found that krill oil preserves the neurons that degenerate in PD — dopaminergic neurons —  and inhibit the accumulation of harmful ⍺-synuclein proteins that drive PD. From analyses of gene activity, Nilsen and colleagues also found that krill oil reprogrammed gene activity to attenuate hallmarks of aging like oxidative stress. What’s more, the Norwegian team found that krill oil treatment improved learning and reduced the predicted age of worms. These findings support the potential for krill oil as a brain-preserving agent that may mitigate age-related cognitive deterioration.

Krill Oil Preserves Cognition-Associated Neurons During Aging

To find how krill oil treatment affects the survival of dopaminergic neurons — neurons that play a crucial role in cognition and movement, Nilsen and colleagues used a PD worm model. In PD, dopaminergic neurons degenerate with age, leading to cognitive decline and movement disorders. Like PD patients, PD worms are known to possess dying dopamine neurons as they age, an attribute associated with reduced learning abilities and motor function. Treating these worms with krill oil significantly prevented the death of dopamine neurons, resulting in higher numbers of these neurons throughout the PD worms’ lifespans. Moreover, less PD-related ⍺-synuclein buildup was observed in krill oil-treated worms and likely contributed substantially to the dopaminergic neuron preservation. These findings suggest that krill oil rescues PD worms’ dopamine neuron survival, which may translate to preserving cognitive function with age.

krill oil treatment preserves neurons
(SenGupta et al., 2022 | Aging) Krill oil treatment preserves neurons and abrogates the harmful buildup of ⍺-synuclein proteins in neurons. Although cognition-associated dopamine neuron survival declined with age from days one, three, and six (D1, D3, D6, respectively) in untreated worms (blue), krill oil (red) preserved their survival (Figure B). ⍺-synuclein levels dramatically increased in PD worms at day six (D6) compared to day one (D1), yet krill oil treatment substantially abrogated this buildup (Figure D).

To get a better idea of how krill oil protects dopaminergic neurons, Nilsen and colleagues performed gene activity analyses by measuring the mRNA levels of many genes (transcriptomics) after treatment. Intriguingly, they found that krill oil suppresses genes related to oxidative stress. The krill oil also suppresses factors related to mitochondrial dysfunction and cellular aging (senescence). Moreover, krill oil enhances neuronal communication (synaptic transmission)-related gene programs. These results suggest that krill oil’s benefits include modulating gene activation programs that mitigate hallmarks of aging to preserve dopaminergic neurons.

The Small Crustacean’s Lipid Extract Enhances Cognition and Reduces Predicted Biological Age

Nilsen and colleagues next determined whether krill oil-induced neuron preservation translates to better cognitive function. They set up an experiment where worms needed to remember the location of food, marked by the presence of a compound that worms can detect called butanone. Interestingly, krill oil-treated PD worms dramatically outperformed non-treated worms on this learning task. The healthy, krill oil-treated worms also exhibited a significantly reduced age as predicted by an aging calculator that measures gene activity. These data suggest that krill oil improves the length of a healthy lifespan (healthspan) by mitigating age-related cognitive decline and reducing worms’ predicted biological age.

krill oil attenuates cognitive decline
(SenGupta et al., 2022 | Aging) Krill oil attenuates age-related cognitive decline and reduces the predicted biological age. The learned association between the presence of a compound that worms can detect called butanone and food (Learning Index) was significantly enhanced in PD worms treated with krill oil (red) compared to untreated (blue) worms (Figure A). Krill oil-treated healthy worms (orange) exhibited a reduced biological age (Predicted age) compared to untreated worms (turquoise) as measured with a genetics-based aging calculator.

“In a C. elegans model of Parkinson’s disease, we show that krill oil protects dopaminergic neurons from aging-related degeneration, decreases alpha-synuclein aggregation, and improves dopamine-dependent behavior and cognition,” said Nilsen and colleagues

Research on marine oils like fish oil to attenuate the effects of aging is picking up pace. However, krill oil studies are lacking. This may be attributable to krill oil only recently coming to the forefront as a possible age-related disease-mitigating substance.

A few other promising studies on krill oil’s benefits include a rat study that suggests krill oil may ameliorate obesity by providing antioxidant defense and modulating lipid metabolism. What’s more, another study has suggested that krill oil may prevent atherosclerosis in rats by reducing cholesterol levels. These studies could pave the way for a new wave of krill oil popularity.

This potential cognitive decline-preventing extract can be purchased as a supplement. Krill oil prices range from about $40 to $120 for a month’s supply of 60 capsules.