Photo/Illutration A team of researchers at Nagoya University announces on Nov. 12 that it developed an insulin-free therapy for patients with type 1 diabetes, at the university in Nagoya. (Shunsuke Kimura)

NAGOYA--A Nagoya University research team has devised a treatment method for type 1 diabetes, which is expected to lead to the development of a daily nasal spray for lowering blood sugar levels.

"(Daily) insulin injections are the only internal medicine treatment currently available for those suffering from type 1 diabetes," said team member Ryoichi Banno, an associate professor of endocrinology and metabolism at the university. "The new technology may help reduce the burden on patients."

The research team announced Nov. 12 ahead of World Diabetes Day on Nov. 14 that an experiment using mice showed that the newly developed method can lower blood sugar levels.

Type 1 diabetes can develop when the pancreas is unable to secrete insulin. An estimated 100,000 to 140,000 people suffer from the disorder in Japan.

Patients with the condition need to take an insulin injection four to five times a day, while fluctuations in their blood sugar levels must be carefully monitored as well, according to the scientists.

In devising the new technique, the team researched an appetite-inhibiting hormone called leptin that is secreted from fat cells and a protein that blocks the activity of leptin.

When leptin and a drug that inhibits the function of the anti-leptin protein were administered to mice modified to develop type 1 diabetes, the researchers found that their blood sugar levels dropped.

"Having effects on the central nervous system, sugar in the blood was likely taken into cells, resulting in lower blood sugar levels," Banno said.

The team said it will continue its research to identify the specific mechanisms behind the decrease in blood sugar.

The researchers are considering conducting leptin injection or nasal spray per day and administering the drug for treating type 1 diabetes.

Nagoya University said it has applied for patents covering such treatment methods in Japan.