Study shows how high blood sugar damages the vascular system

Diabetes, which is characterized by an increase in the level of glucose in the body, eventually leads to certain complications, including cardiovascular disease. Now, a new study shows a cellular link between diabetes and narrowing of blood vessels, which increases the risk of developing chronic and life-threatening health problems, including stroke and heart disease.

A team of researchers from the University of California – Davis Health has discovered a link between diabetes and vascular disease, one of its major complications.

The researchers hope that the results of the study will help formulate new treatments for diabetes, beyond the simple control and monitoring of blood glucose. The cell-level connection can help new treatments target the molecular source of the damaging effects of hyperglycemia on blood vessels.

The Navedo laboratory team is investigating how diabetes increases the risk of serious diseases such as heart disease and stroke. From left to right, Debapriya Ghosh, Gopireddy Reddy, Arsalan Syed, Manuel Navedo, Madeline Nieves-Cintrón and Thanhmai Lee. Image Credit: UC Regents / UC Davis Health

Protein kinase A increases the activity of calcium channels and the constriction of blood vessels

In the past, the team had conducted a similar study, badyzing hyperglycemia or hyperglycemia and triggering it by an enzyme called protein kinase A (PKA), which stimulates the action of the cbads. calcium, causing constriction of the blood vessels.

"It was a surprise, because the PKA is usually badociated with the widening of blood vessels and is not really part of our radar.We wanted to understand the molecular processes behind this opposite reaction "said Manuel Navedo, professor of pharmacology at UC Davis Health.

But the mechanism by which glucose activates PKA remains unclear, the researchers noted. In the study published in The Journal of Clinical Investigation, they showed that elevation of extracellular glucose triggers cyclic adenosine monophosphate (cAMP), the second vital messenger for biological processes and cellular messenger having a vital role in vascular cell function, as well as in production. of arterial myocytes, which largely depended on the activity of adenylyl cyclase 5 (AC5). .

To achieve their results, the team performed experiments on the impact of high glucose on arterial cells and cerebral blood vessels, which control and maintain blood flow in the vessels. The researchers tested these products in laboratory mice, two mouse models of diabetes and a genetically modified mouse.

Specifically, they focused on the connection between PKA and adenylyl cyclase (AC), an enzyme involved in the production of cyclic AMP (cAMP). They discovered that AC5 facilitated the activation of cAMP and PKA, stimulating the increase of calcium channel activity and vasoconstriction of blood vessels. They also discovered that AC5 was crucial for vasoconstriction of blood vessels during diabetes.

Vascular complications in diabetes

Vascular complications during diabetes are the major risk factors for cardiovascular disease, such as hypertension, heart disease and stroke. These complications are often badociated with an increase in blood glucose or hyperglycemia.

The team plans to do further tests on the impact of the AC5 chain reaction in humans. The study could pave the way for new therapeutic approaches aimed at reducing vascular complications of diabetes.

Many patients in clinics and hospitals are battling diabetes and its complications, particularly those that damage the body's vital organs, including the heart, kidneys and brain. The study on the vascular effects of high glycemia at the cellular level could pave the way for new treatment modalities to combat diabetes and cardiovascular disease.

What is diabetes?

Diabetes is a disease that occurs when blood glucose, also known as blood glucose, is too high. Insulin, a hormone produced and released by the pancreas, contributes to the uptake of glucose into cells for energy use.

In diabetes, the pancreas does not produce enough insulin or does not produce insulin at all. As a result, glucose stays in the blood. Although glucose is the main source of energy in the body, if it does not enter the cells and stays in the blood, it can have adverse effects on the various organs of the body.

In the long term, too much glucose or sugar in the blood can lead to complications, including kidney disease, cardiovascular disease, neuropathy and vision loss.

Worldwide, the number of people with diabetes rose from 108 million in 1980 to 422 million in 2014. This number has increased in recent years, particularly in low- and middle-income countries.

In 2016 alone, approximately 1.6 million deaths were related to diabetes and 2.2 million deaths were attributed to high blood glucose in 2012.