Possible therapeutic effects of stigma and its petal flavonoid, kaempferol, on respiratory disorders.

CONTEXT

L. (Iridaceae), or saffron, has been used as food additives and spices. In the traditional medicine of Iran, has been used for the treatment of liver disorders, coughs, and as an anti-inflammatory agent for eyes.

OBJECTIVE

The current study reviewed the possible therapeutic effects of stigma and its petal flavonoid (kaempferol) on respiratory disorders with several mechanisms such as anti-inflammatory, and smooth muscle relaxant effects.

MATERIALS AND METHODS

This review article searched databases including PubMed, Google Scholar, and ScienceDirect, up to November 2019. The keywords including; '', 'saffron', 'kaempferol', 'airway inflammation', and 'smooth muscle relaxant' were searched.

RESULTS

reduced nitric oxide (NO), inducible nitric oxide synthase (iNOS) levels and inflammatory cytokines in the lung tissue. Saffron and kaempferol reduced white blood cells (WBCs) and the percentage of neutrophils and eosinophils in bronchoalveolar lavage fluid. Moreover, saffron reduced tracheal responsiveness to methacholine and ovalbumin on tracheal smooth muscles. In addition, kaempferol reduced the total leukocyte and eosinophil counts similar to the effect of dexamethasone and also showed relaxant effects on smooth muscle.

DISCUSSION AND CONCLUSION

and its petal flavonoid, kaempferol, showed relatively potent therapeutic effects on respiratory disorders by relaxation of tracheal smooth muscles via stimulatory or blocking effects on β-adrenoceptor and muscarinic receptors, respectively. Saffron and kaempferol also decreased production of NO, inflammatory cytokines and chemokines in respiratory systems.