Sea lion struck down by epilepsy connected to global warming
A SEA LION in California has had pioneering brain surgery for epilepsy, offering hope for the growing number of marine mammals suffering from the disorder as a result of climate change.
Cronutt, a seven-year-old sea lion, was treated by a team of 18 specialists from the University of California, San Francisco (UCSF) who have developed a cellular therapy aimed at reversing epilepsy in animals.
The procedure involved injecting embryonic pig brain cells into the hippocampus, the area of the brain responsible for seizures. Scientists hope that the injected cells will spread through Cronutt’s damaged brain over the next few weeks and repair the area.
If successful, the treatment could offer a lifeline to the increasing numbers of sea lions and sea otters developing epilepsy due to exposure to domoic acid – a toxin released by algae blooms.
The algae has become more widespread as the oceans warm, producing toxins that are ingested by small fish such as sardines and anchovies, which in turn are eaten by sea lions.
Sea otters have also suffered from brain damage after ingesting toxinladen shellfish. The animals suffering from the condition frequently get stranded on land, lose their appetite and often die.
The phenomenon was first discovered in 1998 but cases are on the rise as t he world’s ocean t emperatures increase. According to the UCSF, hundreds of sea creatures are affected by domoic acid poisoning on America’s west coast each year.
Researchers first discovered Cronutt in 2017 when it wandered into a car park after running aground. The sea lion was released back into the sea with a tag, but was shortly found again on a nearby beach, where it clambered on top of tables. Its condition deteriorated and it had a massive seizure last month.
Carers at the Six Flags Discovery Kingdom in Vallejo described the surgery as a last-ditch effort to treat the sea lion before considering euthanasia.
The procedure, performed on Oct 6, has previously proved effective in curing mice, but this was the first attempt to use the therapy on larger mammals.
“Over the years I’ve come to learn how many marine mammals can’t be released into the wild due to domoic acid poisoning, and it’s our hope that if this procedure is successful it will open the door to helping many more animals,” said Scott Baraban, a professor of neurosurgery at UCSF.
The early stages of Cronutt’s recovery suggest reasons for optimism – the sea lion was alert and appeared to have regained its appetite in the days following the procedure.
After a meal of 2lb of herring, he “foll owed me all around, was super engaged, and really alert”, carer Dianne Cameron told The New York Times. “His eyes look beautiful,” she added.
However, even i f the operation proves to be a success it is unlikely that the surgery will help people with epilepsy anytime soon, in part because of the challenges of using pig cells in human brains.
‘It’s our hope that if this procedure is successful it will open the door to helping many more animals’