The 25.8 million Americans who have diabetes1 may soon be free of finger pricks2(刺,扎) and daily insulin dosing. Mayo Clinic endocrinologists(内分泌学家) Yogish Kudva, M.B.B.S., and Ananda Basu, M.B.B.S., M.D., are developing an artificial pancreas(胰腺) that will deliver insulin automatically and with an individualized precision never before possible. As part of this effort, Drs. Kudva and Basu will present their latest findings on how the mundane3(世俗的,平凡的) movements of everyday life affect blood sugar to the American Diabetes Association (http://www.diabetes.org/) meeting this month in San Diego.
"The effects of low-intensity physical activity, mimicking4 activities of daily living, measured with precise accelerometers(加速计) on glucose5(葡萄糖) variability in type 1 diabetes had not been examined," says Dr. Kudva.
Among his newest findings is that even basic physical activity after meals has a profound impact on blood sugar levels for people with type 1 diabetes (http://www.mayoclinic.com/health/type-1-diabetes/DS00329). "You would expect this result, but we wanted to know to what extent this phenomena6 would happen in people with type 1 diabetes," Dr. Kudva says.
Diabetics who engaged in low-grade physical activity after eating had blood sugar (http://www.mayoclinic.com/health/blood-sugar/MM00641) levels close to those of people with fully7 functioning pancreases. Those who remained sedentary(久坐的) after their meal, however, had elevated blood sugars.
The researchers plan to incorporate these findings into an artificial pancreas being developed at Mayo Clinic. The "Closed Loop System" under development includes a blood sugar monitor, an automatic insulin pump, a set of activity monitors that attach to the body and a central processing unit.
Clinical trials of the artificial pancreases are likely to begin in November with a handful of inpatient volunteers. Study participants will follow strict diet, exercise and insulin-delivery regimens in Mayo's Clinical Research Unit (http://ctsa.mayo.edu/resources/clinical-research-unit.html). Data will then be fed into an insulin-delivery algorithm(算法) , which mimics8 the body's natural process of monitoring and responding to glucose levels in the bloodstream.
"Physical activity enhances insulin action, hence lowering blood glucose concentration," Dr. Kudva says. "Real-time detection of physical activity -- and modeling of its effect on glucose dynamics9 -- is vital to design an automatic insulin delivery system."
Dr. Kudva and other Mayo researchers have spent nearly 15 years working on various aspects of diabetes and obesity10 (http://www.mayoclinic.com/health/obesity/DS00314). They are collaborating11 on the artificial pancreas and developing an algorithm that will afford patients the peace of mind to eliminate their daily routine of diabetes maintenance(维护,保持) .
Dr. Basu will present findings that blood sugar levels decrease faster in the mornings in healthy adults than at dinner time, suggesting a diurnal12(白天的) pattern to natural insulin action. He proposes further study of this phenomenon and possible incorporation13 into the algorithm that drives the Closed Loop System.