Researchers close in on cure for Type 1 diabetes
Scientists may be getting closer to finding a stem cell cure for Type 1 diabetes—the type that may require insulin injections for life—after conducting stem cell transplants on mice.
A group of researchers in California said they managed to reverse the
equivalent of Type 1 diabetes in mice by transplanting stem cells.
"Here, we describe a stepwise method in which pluripotency
reprogramming factors were transiently expressed in fibroblasts in
conjunction with a unique combination of soluble molecules to generate
definitive endoderm-like cells that did not pass through a pluripotent
state. These endoderm-like cells were then directed toward pancreatic
lineages using further combinations of small molecules in vitro," they said.
They added the resulting pancreatic progenitor-like cells "could mature
into cells of all three pancreatic lineages in vivo, including
functional, insulin-secreting β-like cells that help to ameliorate
hyperglycemia."
"Our findings may therefore
provide a useful approach for generating large numbers of functional β
cells for disease modeling and, ultimately, cell-based therapy," they
said.
Authors of the paper include Ke Li,
Saiyong Zhu, Holger A. Russ, Shaohua Xu, Tao Xu, Yu Zhang, Tianhua Ma,
Matthias Hebrok, and Sheng Ding.
A separate report on UK's The Guardian said the researchers' experiments replaced cells in the pancreas unable to make insulin after being damaged by diabetes.
Without insulin, the body will have a hard time absorbing sugars such
as glucose from blood. Presently, glucose levels can be monitored and
regulated with insulin injections.
The
researchers from the Gladstone Institutes in San Francisco collected
skin cells (fibroblasts) from laboratory mice and treated them with a
mix of molecules and reprogramming factors.
The
cells were transformed into endoderm-like cells, the type that
eventually mature into the body's major organs including the pancreas.
Li, the lead author, said they used another chemical cocktail to turn
these endoderm-like cells into cells that mimicked early pancreas-like
cells (PPLCs).
"Our initial goal was to see
whether we could coax these PPLCs to mature into cells that, like
ß-cells, respond to the correct chemical signals and – most importantly –
secrete insulin. And our initial experiments, performed in a petri
dish, revealed that they did," Li said.
When the
team injected these cells into mice genetically modified to have high
glucose levels to mimic the Type 1 diabetes in humans, the mice's
glucose levels started to decrease and approach normal levels "just one
week post-transplant."
"And when we removed the
transplanted cells, we saw an immediate glucose spike, revealing a
direct link between the transplantation of the PPLCs and reduced
hyperglycemia [high glucose level]," Li said.
Even better, the researchers found the pancreas-like cells turned into
fully functional insulin-secreting ß-cells, eight weeks after the
transplantation.
