Compound Shows Promise As Vaccine-like Drug For Preventing Type 1 Diabetes

The synthetic compound, called ISO-1, appears to work by blocking a pathway involved in inflammation. If successful as a vaccine-like drug, it could ultimately save lives, reduce health care costs and help prediabetic people avoid a lifetime of insulin injections, the researchers say. Their work was described today at the 227th national meeting of the American Chemical Society, the world's largest scientific society.

"We believe this is the most promising compound to date for preventing type 1 diabetes," says study leader Yousef Al-Abed, Ph.D., an associate investigator at North Shore-Long Island Jewish Research Institute in Manhasset, N.Y. "If it works, it will be especially beneficial for young people, who often have a difficult time managing their diabetes with daily insulin injections."

The compound targets prediabetic individuals, defined as those who have blood markers — either antibodies or genetic markers — that are predictive of the disease. Using certain blood tests, many of these individuals can now be identified long before they actually develop type 1 diabetes (also known as juvenile diabetes). More testing is needed before the compound is ready for human use, which could be several years, say Al-Abed and his associates, who hope to develop the compound into a long-acting oral drug.

When ISO-1 was given via injection over a ten-day period to mice that were also given a chemical designed to induce a form of type 1 diabetes, ISO-1 completely protected them from developing the disease. By contrast, all of the mice treated only with the diabetes-inducing chemical developed the disease. In a similar controlled experiment, ISO-1 was given via injection to mice that were genetically bred to develop diabetes, preventing the onset of diabetes in 90 percent of the treated mice, the researchers say.

In both groups of mice receiving ISO-1, the animals continued to make insulin throughout the duration of their treatment and did not show any signs of adverse effects from the compound. The benefits were long-lasting, according to Al-Abed, since ISO-1 protected the animals from developing the disease for up to two months after the treatment was stopped.

The investigators believe that ISO-1 works by blocking a recently identified protein called macrophage migration inhibitory factor (MIF), which appears to play a major role in the cascade of inflammatory events leading to the destruction of pancreatic beta cells, which normally produce insulin, and the subsequent onset of the disease.

Although an increasing number of compounds are being designed to fight diabetes by targeting inflammation, the current study represents the first attempt to prevent type 1 diabetes by targeting the MIF protein, says Al-Abed, whose group first identified the protein as a possible target to fight the disease.

Because ISO-1 is a relatively small chemical compound, it could be easily developed into an oral drug that functions like a vaccine, says Al-Abed. He predicts that such a drug would only need to be taken a few times by prediabetic people in order to achieve long-lasting protection, perhaps a lifetime.

ISO-1 is being tested in animals to determine whether it will help in the actual treatment of ongoing type 1 diabetes and type 2 diabetes, the more common type. Results are not yet available from these tests, the researchers say.

There is currently no cure for diabetes. A few other research groups worldwide are attempting to develop vaccines to prevent type 1 diabetes, but none of the drug candidates has hit the market. The disease can be controlled and its complications minimized by following a healthy diet, getting exercise and taking prescribed medications as directed, according to health experts.

The Picower Foundation and the North Shore-Long Island Jewish Research Institute provided funding for this study.