Bioelectric hacking creates two-headed flatworms
Researchers says results might influence treatments in regenerative medicine. Anthea Batsakis reports.
Chop a planarian flatworm in half and you’ll get two new fully functioning worms. Now, scientists from the US have rewired the Dugesia japonica flatworm’s bioelectricity, the electric currents that run through its living tissues, so a dismembered worm can grow back with two heads – one at each end.
The researchers, led by Michael Levin from Tuft University, found that bioelectric patterns – rather than stem cells or tissues – determine what planarian flatworms will look like when they have regenerated.
The new work published in the Biophysical Journal builds on Levin’s previous research which showed it is possible to make a planarian grow the head and brains of a different species of flatworm by controlling its bioelectric signals.
Levin and colleagues used the chemical octanol to block the microscopic channels between cells that electrical signals travel through. After this treatment, 25% of the worm fragments regenerated with two heads, 72% regenerated with one head, and the rest didn’t redevelop properly at all.
At first the researchers believed the different regeneration results were because the treatment didn’t work in all cases. But when the regenerated one-headed worms were then chopped up and let regenerate, the same ratio of two-headed and one-head worms occurred.
This means the worms’ bioelectric pattern had been changed in some persistent fashion, but it wasn’t revealed until the worms underwent regeneration again.
The researchers write that their findings might influence regenerative medicine in humans, since hacking into bioelectric patterns could be a relatively easy treatment.
However, the link between this study and regenerative medicine isn’t yet convincing, according to Peter Currie, the director of the Australian Regenerative Medicine Institute at Monash University in Melbourne.
“The implications for regenerative medicine and whether we’d ever be able to use bioelectric fields on our own cells is very unclear,” says Currie, who was not involved in the study. “We’re a long way from the clinic when we’ve only got two-headed worms and bioelectrics.”
The mechanism that produces the phenomenon is still unknown. “There’s no real understanding of why blocking this produces these two heads,” Currie says, but adds: “Cool science can begin with these observations. It’s the start of an interesting journey for them.”