What is death? It might seem one of life’s more straightforward questions but experts’ understanding of the subject continues to evolve and deepen.
Multicellular life forms that emerge from the cells of a dead organism suggest that a “third state” lies beyond life and death.
The discovery has raised fresh questions about what it means to die, and the process of “declaring death” has become “progressively messier”, said Popular Mechanics.
Frogs and pigs
When they’re “provided with nutrients, oxygen, bioelectricity or biochemical cues”, certain cells “have the capacity to transform into multicellular organisms with new functions after death”, said Peter A. Noble and Alex Pozhitkov on The Conversation.
Researchers have found that “skin cells extracted from deceased frog embryos were able to adapt to the new conditions of a petri dish in a lab”. It has also been observed that “solitary human lung cells can self-assemble into miniature multicellular organisms” that navigate their surroundings and “repair both themselves and injured neuron cells placed nearby”.
Yale neurobiologist Nenad Sestan, who analyses slices of tissue from brain banks around the world, enjoyed an “accidental breakthrough” around 10 years ago when “a specimen from London missed the plane”, said Popular Mechanics. Cells die after only a few minutes without oxygen so the delay in the tissue arriving was thought to be “catastrophic”. But when Sestan asked a colleague to dissect a piece of it and let it grow in a petri dish containing cellular nutrients, they found that some cells grew. If living cells could be preserved from a dead brain, “why not try to revive the whole organ”, they thought.
Further studies “achieved stunning results”. Parts of pig brains were revitalised after being retrieved from an abattoir. Four hours after the pigs had died, “neurons were firing, blood vessels were functioning”, and the brain’s immune cells were “chugging along”.
Then the team decided to scale up and perform “mind-blowing” experiments on pigs themselves. When the animals were hooked up to a new life-support system called OrganEx after being dead for an hour, they “looked lifelike, their hearts restarted, and they even moved”.
“It was like, whoa, whoa, what should we do now?” said David Andrijevic, a colleague of Sestan’s.
Ethical dilemma
The development of the “souped-up” life-support system is “reinvigorating a decades-old debate about how our lives end”, said Popular Mechanics.
Over the last 70 years, “scientific advances” like life-support machines have “made it harder and harder to find the line between being a person and being a body”, it added.
Ventilators, which started appearing in hospitals in the 1950s, created an “ethical dilemma”, because if bodies “could breathe indefinitely without recovering or decaying”, when were doctors legally allowed to pronounce them “deceased?”
In some cases, this quandary has lasted for years. In 2013, when a 13-year-old girl, Jahi McMath, underwent surgery, her heart stopped and, two days later, doctors declared her brain-dead. But her family didn’t want to give up so they airlifted her to New Jersey, one of the few US states that allows families to refuse a death declaration on religious grounds. There, her body continued to grow and develop and even began menstruating.
It was only five years later, after she died of complications from liver failure, that all parties involved in her case agreed that she was dead.
But, were the pigs in the OrganEx experiment “still dead” when they appeared to come back to life? “And if a treatment like that ever makes it to humans, what happens to the next Jahi McMath”?