Can Artificial Cells Take Over for Lost Insulin-Secreting Cells?

artificial beta cells

Caption: Artificial beta cell, made of a lipid bubble (purple) carrying smaller, insulin-filled vesicles (green). Imaged with cryo-scanning electron microscope (cryo-SEM) and colorized.
Credit: Zhen Gu Lab

People with diabetes have benefited tremendously from advances in monitoring and controlling blood sugar, but they’re still waiting and hoping for a cure. Some of the most exciting possibilities aim to replace the function of the insulin-secreting pancreatic beta cells that is deficient in diabetes. The latest strategy of this kind is called AβCs, short for artificial beta cells.

As you see in the cryo-SEM image above, AβCs are specially designed lipid bubbles, each of which contains hundreds of smaller, ball-like vesicles filled with insulin. The AβCs are engineered to “sense” a rise in blood glucose, triggering biochemical changes in the vesicle and the automatic release of some of its insulin load until blood glucose levels return to normal.

In recent studies of mice with type 1 diabetes, researchers partially supported by NIH found that a single injection of AβCs under the skin could control blood glucose levels for up to five days. With additional optimization and testing, the hope is that people with diabetes may someday be able to receive AβCs through patches that painlessly stick on their skin.

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Cool Videos: Insulin from Bacteria to You

If you have a smartphone, you’ve probably used it to record a video or two. But could you use it to produce a video that explains a complex scientific topic in 2 minutes or less? That was the challenge posed by the RCSB Protein Data Bank last spring to high school students across the nation. And the winning result is the video that you see above!

This year’s contest, which asked students to provide a molecular view of diabetes treatment and management, attracted 53 submissions from schools from coast to coast. The winning team—Andrew Ma, George Song, and Anirudh Srikanth—created their video as their final project for their advanced placement (AP) biology class at West Windsor-Plainsboro High School South, Princeton Junction, NJ.

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Creative Minds: Potential Diabetes Lessons from Binge-Eating Snakes

Secor with a snake

Stephen Secor/Credit: Secor Lab

Many people would do just about anything to avoid an encounter with a snake. Not Stephen Secor. Growing up in central New York State, Secor was drawn to them. He’d spend hours frolicking through forest and field, flipping rocks and hoping to find one. His animal-loving mother encouraged him to keep looking, and she even let him keep a terrarium full of garter snakes in his bedroom. Their agreement: He must take good care of them—and please make sure they don’t get loose.

As a teen, Secor considered a career as a large-animal veterinarian. But a college zoology course led him right back to his fascination with snakes. Now a professor at the University of Alabama, Tuscaloosa, he’s spent 25 years trying to understand how some snakes, such as the Burmese python shown above, can fast for weeks or even months, and then go on a sudden food binge. Secor’s interest in the feast-or-famine digestive abilities of these snakes has now taken an unexpected turn that he never saw coming: a potential treatment to help people with diabetes.

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Protein Links Gut Microbes, Biological Clocks, and Weight Gain

Fat calls with and without NFIL3

Caption: Lipids (red) inside mouse intestinal cells with and without NFIL3.
Credit: Lora V. Hooper, University of Texas Southwestern Medical Center, Dallas

The American epidemic of obesity is a major public health concern, and keeping off the extra pounds is a concern for many of us. Yet it can also be a real challenge for people who may eat normally but get their days and nights mixed up, including night-shift workers and those who regularly travel overseas. Why is that?

The most obvious reason is the odd hours throw a person’s 24-hour biological clock—and metabolism—out of sync. But an NIH-funded team of researchers has new evidence in mice to suggest the answer could go deeper to include the trillions of microbes that live in our guts—and, more specifically, the way they “talk” to intestinal cells. Their studies suggest that what gut microbes “say” influences the activity of a key clock-driven protein called NFIL3, which can set intestinal cells up to absorb and store more fat from the diet while operating at hours that might run counter to our fixed biological clocks.

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Muscle Enzyme Explains Weight Gain in Middle Age

Woman weighing herself

Thinkstock/tetmc

The struggle to maintain a healthy weight is a lifelong challenge for many of us. In fact, the average American packs on an extra 30 pounds from early adulthood to age 50. What’s responsible for this tendency toward middle-age spread? For most of us, too many calories and too little exercise definitely play a role. But now comes word that another reason may lie in a strong—and previously unknown—biochemical mechanism related to the normal aging process.

An NIH-led team recently discovered that the normal process of aging causes levels of an enzyme called DNA-PK to rise in animals as they approach middle age. While the enzyme is known for its role in DNA repair, their studies show it also slows down metabolism, making it more difficult to burn fat. To see if reducing DNA-PK levels might rev up the metabolism, the researchers turned to middle-aged mice. They found that a drug-like compound that blocked DNA-PK activity cut weight gain in the mice by a whopping 40 percent!

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