Glucosamine inhibits lipopolysaccharide-stimulated inducible nitric oxide synthase induction by inhibiting expression of NF-kappaB/Rel proteins at the mRNA and protein levels

► Expression of iNOS protein in BV2 cells increased in a biphasic manner by LPS. ► Glucosamine suppressed the late- but not early-stage iNOS response to LPS. ► Late-phase activation of NF-κB activity required for sustained iNOS induction. ► Glucosamine inhibits iNOS induction by inhibiting Rel protein expression.