Scientists have been able to utilize human stem cells to rapidly cure diabetes in mice. They accomplished this by emulating the function of naturally occurring pancreatic beta cells that make insulin in our bodies.
Human Pluripotent stem cells (hPSCs) are embryonic cells that are essentially generic or “blank”. They can grow into practically any kind of cell. HPSCs have shown a lot of promise and success over the last few decades. They’ve mostly utilized in the field of regenerative medicine in the treatment of cancer and damaged parts of different organs.
Biomedical engineer Jeffrey R. Millman from Washington University was successfully able to manipulate hPSCs into behaving like pancreatic beta cells that produce insulin. He then transplanted these cells into mice that were suffering from a severe form of induced diabetes. This caused the mice to be rapidly cured.
“When we gave the mice the insulin-secreting cells, within two weeks their blood glucose levels had returned to normal and stayed that way for many months,” said Millman.
How stem cells cure diabetes
Stem cell research often receives pushback from ethical and religious groups that view the process as destructive of “human life”. Scientifically, the challenge has always been more about the body’s acceptance of these “foreign” cells. Another challenge is how well we can ensure we only get the desired type of cells.
Millman’s lab is aware of these challenges. In 2016, they were successfully able to derive insulin-secreting cells from patients with type 1 diabetes. In 2019, they were able to enhance the efficacy of their insulin secretion.
“A common problem when you’re trying to transform a human stem cell into an insulin-producing beta cell – or a neuron or a heart cell – is that you also produce other cells that you don’t want,” Millman explained. “In the case of beta cells, we might get other types of pancreas cells or liver cells.”
His team however discovered that the success rate of lowering “cell differentiation” is linked to the cell’s cytoskeleton. Essentially a set of protein fiber microfilaments that form a support structure within the cells. Namely one of these proteins; actin.
Here’s how the authors of the paper explained it. “We found that manipulating cell–biomaterial interactions and the state of the actin cytoskeleton altered the timing of endocrine transcription factor expression and the ability of pancreatic progenitors to differentiate into stem-cell-derived beta cells.”
“Our study as a whole emphasises that cytoskeletal dynamics work synergistically with soluble biochemical factors to regulate endodermal cell fate, opening new opportunities to improve differentiation outcomes.”
The team was successfully able to manipulate the cytoskeleton to reduce differentiation regardless of the intended target cell type. That makes this discovery relevant for many more applications of regenerative medicine as well.
“We were able to make more beta cells, and those cells functioned better in the mice. Some of which remained cured for more than a year,” said Millman.
Diabetes claims over 1.5 million lives a year worldwide. Diabetes costs the US government $327 billion per year to treat the 34.2 million American adults suffering from it. The cost is likely to continue to rise, with 1.5 million new diagnoses every year in the US alone.
Research estimates the global prevalence of diabetes among adults to be 10.5 percent. With the figure for prediabetes, or Impaired Glucose Tolerance (IGT), following closely at 7.3%. Experts expect both of these figures to continue growing to terrifying degrees over the next couple of decades.
The Dietary Approach
Since the early 90s, there’s been a growing fan base for a dietary approach. They’ve repeatedly suggested, with some scientific backing, that carbohydrate restriction can be used to successfully cure diabetes. This is one of the many marketed benefits of diets like keto and the carnivore diet.
The ketogenic diet works by restricting carb intake enough to force the body into a state of ketosis. This makes the body shift to using stored fat as an energy source instead of relying on an intake of carbohydrates.
The carnivore diet is more restrictive – allowing nothing but meat. It works similarly to keto by also bringing about the process of ketogenesis. Proponents of this diet argue the additional removal of dairy also shows health benefits.
Overwhelming anecdotes praise both of these dietary approaches for their weight loss benefits. More controversially, they claim to cure ailments caused by our modern way of life like diabetes, heart disease and obesity. Anecdotal evidence suggests they also help with certain autoimmune issues and depression.
What does the research say?
The carnivore diet is particularly said to be lacking many nutrients that our bodies require. The more moderate “keto” diet is still heavily criticized for steering away from a “balanced” diet. Pro-keto enthusiasts are critical of balanced diets that encourage large intakes of carbohydrates. They cite the recent rise in obesity and diabetes as proof that our dietary guidelines are to blame. They also argue that the low cost of carbohydrates contributes to their popularity.
Scientific studies done on ketogenic diets do prove some of these benefits, including curing diabetes. Doctors are still hesistent to prescribe or recommend the diet, however. The consensus in the scientific community remains that not enough is known about the potential side effects of carbohydrate restriction to responsibly recommend it. Particularly, there is concern about how different diets and even different eating patterns can affect bacteria in the gut. These changes in gut bacteria can have unforeseeable effects on our overall health.
Another major concern of ketogenic diets is diabetic ketoacidosis (DKA). DKA is a potentially life-threatening condition that occurs when the body burns too much fat within a small time frame. The breakdown of fat releases ketones into the bloodstream. A high concentration of ketones can make the blood acidic, which could lead to severe dehydration or organ problems.
DKA usually occurs as a side effect of diabetes – since insulin otherwise regulates the level of ketones in the blood. This is where Millman’s discoveries show hope to cure diabetes using stem cells that produce insulin.