Israeli Research Links High Blood Sugar to Immune System Dysfunction in Diabetics

Jerusalem, 7 January, 2024 (TPS) -- People with diabetes are more susceptible to complications from respiratory infections, which was underscored by their higher mortality rates during the coronavirus pandemic. But new Israeli medical research is shedding insights into the reasons, and pathways for future treatment.

Diabetes — a chronic health condition that affects how the body uses blood sugar — is known to weaken the body’s immune system as high blood sugar levels impair the body’s ability to create white blood cells.

Poorly managed diabetes can lead to damage in the small blood vessels and nerves, affecting the lungs’ ability to function properly. As a result, diabetics who contract respiratory illnesses are more likely to suffer more severe complications.

More than 500 million people worldwide have diabetes.

Researchers at the Weizmann Institute of Science in Rehovot examined the response of mice models with type 1 and type 2 diabetes to various respiratory viruses. Similar to humans with diabetes, these diabetic mice showed an increased susceptibility to acute and potentially fatal lung infections when exposed to pulmonary pathogens.

The results of the study, led by Prof. Eran Elinav, were recently published in the peer-reviewed scientific journal, Nature.

The Weizman researcher delved into the genetic and cellular aspects by analyzing over 150,000 lung cells from diabetic and non-diabetic mice at a single-cell level. This meticulous investigation revealed a malfunction in a specific subset of immune system cells known as dendritic cells, crucial for initiating an effective immune response against pulmonary infections.

“High blood sugar levels severely disrupt the activity of these lung dendritic cells, hampering their ability to transmit crucial molecular signals necessary for an effective immune response,” explained researcher Dr. Samuel Nobs. He noted that this immune system impairment allowed the infections to spread unchecked in the bodies of the diabetic mice.

The study further identified the mechanism behind this disruption: high blood sugar levels led to altered metabolism in dendritic cells, causing the accumulation of metabolic byproducts. These byproducts interfered with the cells’ genetic control mechanisms, impairing their ability to produce essential proteins crucial for an effective immune response against infections.

Exploring potential solutions, the Weizmann researchers found that tightly controlling blood sugar levels through insulin administration in diabetic mice enhanced the dendritic cells’ ability to mount a robust immune response.

Additionally, administering specific small molecules capable of preventing molecular disruptions in dendritic cells restored their effectiveness in fighting infections, even in the presence of elevated blood sugar levels.

“These discoveries provide hope that the tendency of diabetic patients to develop acute lung infections can be mitigated. They underscore the importance of vigilant monitoring of sugar levels, particularly during illness,” Elinav said.

“Careful blood sugar control may reduce the distinct risk of respiratory infections in diabetic individuals. However, for patients struggling with sugar level management, future drugs based on the small molecules tested in this study could offer a promising solution,” he explained. “Local inhalation treatments with these drugs might amplify their efficacy while minimizing potential side effects.”