Obesity is an enlargement of adipose tissue to store excess energy intake. Excessive calorie intake may lead to the formation of fat cells, promoting their deterioration (aging) by increasing the production of proinflammatory molecules. Low grade inflammation is a key factor in the development of insulin resistance and type 2 diabetes in obesity.

This study characterized miRNAs (small nucleic acids involved in the regulation of gene expression) vehicled by nanovesicles (emerging players in cell-to-cell communication) isolated from walnuts and hazelnuts, and tested their effectiveness on inflammatory and metabolic profile in fat cells.

Researchers found that two conserved plant miRs (miR156c and miR159a) were able to limit inflammatory response and recover insulin sensitivity in obese mice (fed with a high fat diet). Results suggest that nut miRs improve metabolic profile of fat cells and reveal a novel anti-inflammatory function of plant foods (including nuts) as promising therapeutics to treat low-grade inflammation.

"Our research has identified nut nucleic acids that, thanks to their high bioavailability and anti-inflammatory action, are able to limit the development of metabolic diseases linked to obesity" states Dr. Lettieri Barbato, researcher at the University of Rome "Tor Vergata" and principal investigator of this study.