Neutrophil elastase increases insulin resistance

Neutrophils, the first immune cells to respond to tissue inflammation, can promote chronic inflammation by summoning macrophages.

The neutrophils secrete an enzyme known as neutrophil elastase which impairs insulin signalling and boosts insulin resistance, the researchers say.

Scientists showed how the immune cells used the enzyme to activate a signalling pathway which triggered pathogen-eating macrophages to secrete pro-inflammatory cytokines.

When the enzyme was removed from obese mice on high-fat diets, their insulin sensitivity improved.

Nature Medicine 2012; online 5 Aug