Life at high altitudes has long been associated with changes in human physiology, including a reduced incidence of diabetes. The reasons for this phenomenon remained unclear for a long time, but recent research has shed light on the matter.

Historical Studies on the Effects of Altitude

From 1927 to 1947, the Harvard Fatigue Laboratory in Cambridge, Massachusetts, studied the impact of various stress factors on the human body. Special attention was given to the effects of high altitudes to help pilots and military personnel during World War II. During an international expedition to Chile in 1935, it was discovered that hypoxia (a lack of oxygen) increases the production of red blood cells and improves glucose tolerance. Experiments showed that hemoglobin in red blood cells under these conditions reduces its ability to bind oxygen.

In the following years, these findings were repeatedly confirmed and expanded upon, but the mechanism behind improved glucose tolerance during hypoxia remained unclear.

New Discoveries in Hypoxia Mechanisms

A recent study conducted at the Gladstone Institute and published in the journal Cell Metabolism revealed that red blood cells play a key role in this process. It was found that under hypoxic conditions, red blood cells begin to actively absorb glucose from the blood. Glucose is the only energy source for these cells, as they lack mitochondria, which are necessary for converting oxygen into energy.

When oxygen levels drop, red blood cells change their metabolism and start consuming more glucose. This leads to the formation of the molecule 2,3-diphosphoglycerate (2,3-DPG), which weakens the bond between hemoglobin and oxygen, making it easier for tissues to access oxygen.

The Disappearing Glucose: Experimental Data

In previous experiments on mice exposed to low-oxygen conditions, blood glucose levels dropped below normal. Standard target organs such as muscles, brain, and liver could not explain the disappearance of glucose from the bloodstream. The new study showed that it is the red blood cells that, under hypoxia, begin to absorb glucose in large amounts, acting like sponges.

Prospects for Diabetes Treatment

In further experiments, diabetic mice were subjected to hypoxia, and a drug called HypoxyStat, developed at Gladstone to induce hypoxic states in rodents, was also used. In both cases, blood sugar levels returned to normal. HypoxyStat was originally developed to treat mitochondrial diseases, but now its potential use for diabetes is being considered.

This discovery points to new approaches for diabetes treatment based on the ability of red blood cells to absorb glucose when oxygen levels are low, which could be used to control blood sugar levels.