Exp Mol Med.  2004 Dec;36(6):545-550.

Corn silk induces nitric oxide synthase in murine macrophages

• Kim KA
• Choi SK
• Choi HS

Abstract

Corn silk has been purified as an anticoagulant previously and the active component is a polysaccharide with a molecular mass of 135 kDa. It activates murine macrophages to induce nitric oxide synthase (NOS) and generate substantial amounts of NO in time and dose-dependent manners. It was detectable first at 15 h after stimulation by corn silk, peaked at 24 h, and undetectable by 48 h. Induction of NOS is inhibited by pyrolidine dithiocarbamate (PDTC) and genistein, an inhibitor of nuclear factor kappa B (NF-kappaB) and tyrosine kinase, respectively, indicating that iNOS stimulated by corn silk is associated with tyrosine kinase and NF-kappaB signaling pathways. IkappaB-alpha degradation was detectible at 10 min, and the level was restored at 120 min after treatment of corn silk. Corn silk induced nuclear translocation of NF-kappaB by phosphorylation and degradation of IkappaB-alpha.

Keyword

macrophages; nitric oxide; nitric oxide synthase; NF-kappaB

MeSH Terms

Animals
Anticoagulants/*pharmacology
Genistein/pharmacology
I-kappa B/metabolism
Macrophages/drug effects/*enzymology/metabolism
Mice
NF-kappa B/antagonists & inhibitors/metabolism
Nitric Oxide/biosynthesis
Nitric-Oxide Synthase/antagonists & inhibitors/*biosynthesis
Phosphorylation
Plant Extracts/pharmacology
Polysaccharides/*pharmacology
Protein Transport/drug effects
Protein-Tyrosine Kinase/antagonists & inhibitors/physiology
Pyrrolidines/pharmacology
Research Support, Non-U.S. Gov't
Thiocarbamates/pharmacology
Zea mays/*chemistry