Molecular link between cell stress and inflammation
doi:10.1038/nindia.2013.160 Published online 27 November 2013
Resistin, a cell signalling protein secreted by adipose tissue, could be the link between cellular stress and inflammation in humans, new research suggests. Researchers have established that the adipocytokine resistin secreted by human macrophages is retained inside the cell during pathological infections and acts like a chaperone to prevent cell death .
Resistin has earlier been shown as a proinflammatory molecule in humans. The researchers followed up on some unique properties of resistin – its resistance to heat and urea denaturation, concentration-dependent conformational change and an intimate correlation of hRes expression with cellular stress. They showed that recombinant human resistin was able to protect the crucial enzymes citrate synthase and Nde1 from being affected by heat or from getting inactivated.
The researchers used molecular dynamics-based 'association–dissociation' kinetics to point out that resistin was a molecular chaperone.
They treated the human lymphoma cell line U937 with enzyme activity inhibitors tunicamycin and thapsigargin. It resulted in reduced resistin secretion and localisation in the endoplasmic reticulum. Bacterial Escherichia coli cells expressing resistin could be rescued from thermal stress, pointing to its chaperone-like function in vivo. HeLa cells transfected with resistin also showed protection from thapsigargin-induced cell death.
- Suragani, M. et al. Human resistin, a proinflammatory cytokine, shows chaperone-like activity. P. Natl. Acad. Sci. USA. (2013) doi: 10.1073/pnas.1306145110