Using the world's highest mountain, Mount Everest, as an outdoor laboratory, a group of British researchers has identified a mechanism involved in the development of adult onset diabetes. Experts say the findings could lead to development of treatments to prevent the disease.
At more than 8,800 meters above sea level, Mount Everest in Nepal is the world’s highest peak. Climbers require supplemental oxygen because the air is so thin.
Hypoxia, or lack of blood oxygen, is a risk factor for the onset of Type 2 diabetes.
So, researchers with the Mount Everest project sought to identify the mechanisms by which low oxygen levels contribute to disease in patients who are critically ill with diabetes.
, a professor of anesthesia and critical care medicine at Southampton University, led the study, which began at an Everest base camp 5,300 meters above sea level.
The expedition included about 200 climbers. But Grocott says researchers focused on 24 individuals who underwent assessments of glucose control, body weight changes and inflammation biomarkers. The measurements were taken at six weeks and again at two months. Eight climbers then continued their trek to the peak.
In the low oxygen environment, Grocott says the participants' insulin levels began to rise, indicating their bodies were becoming insulin resistant.
There also was an increase in biomarkers of inflammation and oxidative stress, or cellular damage, similar to what’s seen in people with Type 2 diabetes.
On the ground, Grocott says the findings suggest treatments might be developed to prevent the disease.
“Helping to control the tendency towards diabetes may be interventions that are focusing on either the development of this oxidative stress or this inflammation,” says Grocott.
In an article published in the journal PLoS ONE
, investigators report the abnormal biomarkers, caused by the extreme altitude, were reversed once the participants came off the mountain.
Many people who develop diabetes suffer from sleep apnea, in which their airways become obstructed - sometimes hundreds of times per night.
“That is likely to predispose them to certainly intermittent hypoxia during sleep. And that may be something that is contributing toward this tendency to develop Type 2 diabetes,” says Grocott.
Grocott says investigators are now comparing the climbers, most of whom were Caucasian, to the Sherpa to see whether genetic differences protect the indigenous Nepalese population from diabetes.