The trypsin inhibitor from Moringa oleifera flowers (MoFTI) inhibits acute inflammation in mice by reducing cytokine and nitric oxide levels

Abstract The medicinal use of Moringa oleifera flowers to treat inflammations, for examples as constituents of tonics, has been reported. Protease inhibitors isolated from plants have been evaluated as potential anti-inflammatory agents and the edible flowers of Moringa oleifera contain a trypsin inhibitor called MoFTI. In the present work, we evaluated whether MoFTI can be linked to the anti-inflammatory effects reported for M. oleifera flowers. Two mouse models of carrageenan-induced acute inflammation (paw edema and peritonitis) were performed. The animals were intraperitoneally administered MoFTI at 15 or 30 mg/kg. The anti-edematogenic effect was assessed by measuring the paw volume during the first and second phases of edema formation. In the peritonitis model, we evaluated the peritoneal fluid for leukocyte migration, total protein content, cytokine levels, and nitric oxide (NO) concentration. MoFTI reduced paw edema only during the second phase, indicating cytokine modulation. In the peritonitis model, MoFTI reduced leukocyte migration, plasma extravasation (attributed to lower protein content), and the levels of NO and pro-inflammatory [tumor necrosis factor-α, interleukin (IL)-6, and IL-17A] and anti-inflammatory (IL-4 and IL-10) cytokines. In conclusion, MoFTI promoted an anti-inflammatory activity and its action appears to be mediated via cytokine suppression. Hence, MoFTI is an interesting molecule for evaluation in chronic inflammation models, and as a candidate for the development of novel anti-inflammatory drugs.