Immune Cell Depletion May Increase Risk of Diabetes, Hypertension

Increasing eosinophils led to normal perivascular adipose tissue function.

Results from a new study published by Scientific Reports suggest that immune cells may be used as a new way to prevent diabetes and hypertension, in which these cells are significantly reduced.

Specifically, the authors analyzed the potential role of eosinophils, which are located in the perivascular adipose tissue (PVAT) that surrounds blood vessels and maintains their function by reducing artery contractions.

In the new study, the authors discovered that eosinophils were reduced in mice models of obesity. This was observed to reduce PVAT function, which increased the risk of developing type 2 diabetes and hypertension, according to the study.

"This type of immune cell is present in many parts of the body and was once thought to just act in parasitic infections and allergies, but it's fast becoming clear that they have a significant effect on lots of aspects of health and immunity,” said lead researcher Sheena Cruickshank, PhD. "Our study showed that in fact the secretions from eosinophils have a profound effect on how the blood vessels operate and when they are missing, as in obesity, serious health problems can start to develop."

This finding opens new opportunities for investigators to develop treatments for type 2 diabetes and hypertension through targeting eosinophil levels in PVAT.

The authors found that PVAT from fat without eosinophils can be supplemented with additional immune cells to restore function, according to the study. They also discovered that eosinophils influenced the release of nitric oxide and adiponection, which plays a role in normal PVAT function. The investigators reported that this mechanism is unique to eosinophils.

The authors noted that adding eosinophils rapidly restored healthy PVAT function, which demonstrates how potent this therapy may be in humans. Patients may be able to immediately benefit from this treatment or prevent diabetes or hypertension onset.

Additional studies are needed to observe if these findings are confirmed in human patients with diabetes or hypertension. Since patients with diabetes are at a higher risk of developing heart disease, restoring eosinophils in PVAT may prevent the onset of both conditions.

“These immune cells have been traditionally overlooked but this study shows for the first time that they have a direct role to play in processes in the body beyond the immune system,” Dr Cruickshank concluded. “They seem to be incredibly important in a number of processes and this presents us with an exciting new area to investigate for a whole range of illnesses.”