Lab-Grown Muscle Sucks Up Sugar to Fight Diabetes
Your muscles do more than help you move your body. They also help keep your blood sugar in check. That’s because muscles use sugar (glucose) for fuel, clearing it from the blood and lowering blood sugar as a result.
“The skeletal muscle tissue is the largest tissue by mass in the body and requires a big portion of the body’s total energy,” says Hagit Shoyhet-Smoilovsky, PhD, a researcher at the Israel Institute of Technology. “It’s responsible for taking up a significant percentage of glucose from the blood, making it crucial in glucose homeostasis.”
However, when you have type 2 diabetes, this process doesn’t work as well, Shoyhet-Smoilovsky says. The hormone insulin helps shuttle glucose into cells, and because type 2 diabetes often comes with insulin resistance (when cells don’t respond well to insulin), that means glucose can be harder for muscles to access.
Exercise can help your muscles use more sugar, which is why it’s one of the first interventions recommended for diabetes. Still, many patients must take medication and, in some cases, daily insulin injections to control their blood sugar.
Now scientists have found a way to genetically engineer muscle capable of soaking up significantly more sugar than normal. Previous results using mouse muscle cells proved promising, and now researchers have started working with human muscle cells. This latest research, which has not been published yet, was presented at the annual meeting of the European Association for the Study of Diabetes in Stockholm, Sweden.
The idea is to inject the tissue into diabetes patients, boosting their muscle’s ability to pull glucose from the blood and control blood sugar, explains Shoyhet-Smoilovsky. If this treatment pans out, it could reduce the need for insulin injections someday.
Growing Muscle
The key here is something called glucose transporter type 4, or GLUT4. When activated by insulin, this protein helps cells absorb sugar so they can use it for energy. The team modified human muscle cells to produce more GLUT4.
These cells were used to grow 3D tissue with the texture and consistency of muscle. Using a fluorometer to measure glucose molecules, the researchers found that the new tissue soaked up 50 percent more sugar than normal muscle tissue, Shoyhet-Smoilovsky says. When the tissue was surgically transplanted into diabetic mice, the rodents’ blood sugar fell by 20 percent in about a month.
The team also developed a flexible scaffold that could allow the tissue to be injected through a syringe, meaning the treatment could be administered via injection rather than surgery, Shoyhet-Smoilovsky adds.
Next Steps
Several steps must be taken before the treatment can be tested in humans, says Shoyhet-Smoilovsky. If all goes well and they reach human trials, they may try using a patient’s own muscle cells to reduce chances of rejection, she notes.
Shoyhet-Smoilovsky emphasized that the goal is not to replace lifestyle changes that can meaningfully reduce and control diabetes. “We simply aim to offer additional tools to battle the disease,” she says. “These types of tools are urgently needed.”
Still, this technology could lead to other therapies that provide the benefits of exercise without working out. For instance, it could be used to increase muscle mass in those with limited mobility or older adults, or to treat muscle diseases like multiple sclerosis, muscular dystrophy, and neuromuscular disorders.
“We believe our technology can be useful in other pathologies involving skeletal muscle as well,” Shoyhet-Smoilovsky says. “Of course, each type of condition will have to be studied individually.”
Sources:
Hagit Shoyhet-Smoilovsky, PhD candidate, researcher in the stem cell and tissue engineering lab, Israel Institute of Technology.
Science Advances: “GLUT4-overexpressing engineered muscle constructs as a therapeutic platform to normalize glycemia in diabetic mice.”
Source: Read Full Article