RESUMEN
This study investigated the anti-inflammatory activity of the extract (LEG) and purified (LPG) lycopene from guava (Psidium guajava L.), as well as some mechanisms possibly involved in this effect. The anti-inflammatory activity was initially assessed using paw edema induced by Carrageenan, Dextran, Compound 48/80, Histamine and Prostaglandin E2 in Swiss mice. A peritonitis model was used to evaluate neutrophil migration, the activity of myeloperoxidase (MPO) and reduced glutathione (GSH) concentration; while the effect on the expression of iNOS, COX-2 and NF-κB, was assessed by immunohistochemistry analysis. Results showed that oral and intraperitoneal administration of LEG and LPG inhibited inflammation caused by carrageenan. LPG (12.5mg/kg p.o.) significantly inhibited the edema formation induced by different phlogistic agents and immunostaining for iNOS, COX-2 and NF-κB. Leukocytes migration in paw tissue and peritoneal cavity was reduced, as well as MPO concentration, whereas GSH levels increased. Thus, lycopene-rich extract from red guava has beneficial effect on acute inflammation, offering protection against the consequences of oxidative stress by downregulating inflammatory mediators and inhibiting gene expression involved in inflammation.