Age and obesity-related inflammation linked with heart disease in new study

A new study has found a link between advancing age, obesity-related inflammation and coronary microvascular disease (CMD).
CMD is a heart condition that affects the walls and inner lining of tiny coronary artery blood vessels that branch off from the larger coronary arteries.
High levels of inflammation in older and obese adults, combined with a history of heart disease, high blood pressure or type 2 diabetes, can elevate CMD risks.
Looking at data in mice and human heart tissue extracted during surgery, researchers from Augusta University found links between developing CMD disease and inflammation.
The findings suggest that inflammation in the lining of blood vessels walls appears to be a marker of ongoing cellular injury leading to CMD.
Researchers reported in the journal Arteriosclerosis, Thrombosis, and Vascular Biology, that this manifests as a loss of elasticity and impaired blood flow in small vessels.
Inflammation occurs locally through an upregulation of proinflammatory cytokines and researchers believe they found what sets it off in blood vessels.
An enzyme called ADAM17, which is highly expressed in fat tissue and the epithelial cells of blood vessel walls of older, obese humans, is of particular interest.
As it turns out, ADAM17 can release the cytokine molecule tumor necrosis factor (TNF) alpha into the bloodstream where it targets the heart.
Moreover, ADAM17 increases in activity with advancing age, while its natural inhibitor compound, caveolin-1, that prevents inflammation from spreading, decreases with age.
When researchers tried transplanting fat from aged obese mice (expressing ADAM17) to younger ones, they saw increased levels of inflammation and blood vessel injuries.
Inflammation-mediated CMD can easily go undetected during routine exams as it only involves tiny blood vessels, leaving larger blood vessels intact in the early stages.
Overall, the findings show that age and obesity-related inflammation have an additive effect that may lead to CMD and higher heart disease risks.