A study in Norway reported that krill oil can be used to protect neurons from degeneration related with aging. Researchers found that krill oil rewires distinct gene expression programs that contribute to reducing a number of aging-related chemical changes in the cell. The study was published in Aging.
Krill are a type of small crustaceans that are found across the oceans of the world. They are most widely known as being the primary food of different species of whales. Health promoting properties of oils obtained from marine creatures have attracted lots of scientific attention. This includes oil obtained from krill. Mechanisms through which these oils achieve beneficial health effects are not fully understood. They are a topic of intensive scientific research.
What is known is that extracts from a certain species of Antarctic krill have a high content of long-chain omega-3 fatty acids. “These fatty acids are important in the brain with diverse roles ranging from maintenance of brain structure and function and serve as essential building blocks of healthy cell membranes,” the study authors explain. In krill oil, these acids are mainly bound to phospholipids, compounds that improve tissue uptake of the substance and facilitate its efficient delivery to the brain.
One of the health benefits of oils obtained from marine animals are their possible effects on biological processes related with aging. Aging is the primary risk factor for many major diseases. Scientists hope that interfering with biological processes responsible for aging could extend the healthy lifespan of individuals.
Previous studies have found that krill oil can extend the lifespan in a type of worm (nematodes) by about 4 days. Study authors Tanima SenGupta and her colleagues wanted to further explore this phenomenon, to test whether this effect might be based on the countering of aging-related processes and also see whether similar effects can be observed in human cells.
They particularly wanted to focus on studying the effects of krill oil on dopaminergic neurons. These neurons are found in the midbrain and are the primary source of the neurotransmitter dopamine. Their loss is associated with the development of the Parkinson’s disease, which is one of the most prominent human neurological disorders.
Researchers cultured several strains of nematodes using precisely specified procedures. These included transgenic strains that had certain human genes, strains previously used to study Parkinson’s disease using these animals as the model. These nematodes are good models to study human neurons as their own nerve cells have properties that are very similar to those of humans. This means that effects observed in these particular nematodes very likely are the same ones that would be found if human dopaminergic neurons were studied.
Researchers also grew a human fibroblastoid cell line. These cells produce the structural framework for tissues and play a critical role in wound healing. They then performed a number of procedures to make the cells of Caenorhabditis elegans nematodes as good models of dopaminergic neurons in humans as possible and to test effects of interest on them. They divided the animals into 2 groups – one was fed krill oil and the other was not.
The results showed that krill oil rewires distinct gene expression programs that contribute to attenuating several hallmarks of aging. These include oxidative stress, proteotoxic stress, senescence, genomic instability, and mitochondrial dysfunction. Krill oil was found to increase the resilience of neurons through a process called temporal transcriptome rewiring that promotes anti-oxidative stress and anti-inflammation. Krill oil was also found to promote the survival of dopaminergic neurons through regulation of synaptic transmission and neuronal functions via certain genes (PBO-2 and RIM-1).
“We show that krill oil protects dopaminergic neurons from age-related degeneration and enhances dopamine-dependent behavior and cognition in C.elegans Parkinson’s disease models. We show that krill oil promotes healthy ageing by counteracting many processes that drive aging. Specifically, krill oil suppresses accumulation of oxidative DNA damage, counteracts loss of mitochondrial membrane potential and function, suppresses senescence, and reduces α-SYN aggregation in old animals,” the study authors conclude.
The study makes an important contribution to the scientific knowledge of biochemistry of aging. However, it also has limitations that need to be taken into account. Notably, the study was based on nematode models of human dopamine neurons to which krill oil was administered. It is possible that its effects in humans differ.
The study, “Krill oil protects dopaminergic neurons from age-related degeneration through temporal transcriptome rewiring and suppression of several hallmarks of aging”, was authored by Tanima SenGupta, Yohan Lefol, Lisa Lirussi, Veronica Suaste, Torben Luders , Swapnil Gupta, Yahyah Aman, Kulbhushan Sharma, Evandro Fei Fang, and Hilde Nilsen.
