Thionamides inhibit the transcription factor nuclear factor-kappaB by suppression of Rac1 and inhibitor of kappaB kinase alpha.

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Citation

Humar M, Dohrmann H, Stein P, Andriopoulos N, Goebel U, Roesslein M, Schmidt R, Schwer CI, Loop T, Geiger KK, Pahl HL, Pannen BH

Thionamides inhibit the transcription factor nuclear factor-kappaB by suppression of Rac1 and inhibitor of kappaB kinase alpha.

J Pharmacol Exp Ther. 2008 Mar;324(3):1037-44. Epub 2007 Nov 30.

PubMed ID
18055877 [ View in PubMed
]
Abstract

Thionamides, inhibitors of the thyroid peroxidase-mediated iodination, are clinically used in the treatment of hyperthyroidism. However, the use of antithyroid drugs is associated with immunomodulatory effects, and recent studies with thionamide-related heterocyclic thioderivates demonstrated direct anti-inflammatory and immunosuppressive properties. Using primary human T-lymphocytes, we show that the heterocyclic thionamides carbimazole and propylthiouracil inhibit synthesis of the proinflammatory cytokines tumor necrosis factor (TNF)alpha and interferon (IFN)gamma. In addition, DNA binding of nuclear factor (NF)-kappaB, a proinflammatory transcription factor that regulates both TNFalpha and IFNgamma synthesis, and NF-kappaB-dependent reporter gene expression were reduced. Abrogation of NF-kappaB activity was accompanied by reduced phosphorylation and proteolytic degradation of inhibitor of kappaB (IkappaB)alpha, the inhibitory subunit of the NF-kappaB complex. Carbimazole inhibited NF-kappaB via the small GTPase Rac-1, whereas propylthiouracil inhibited the phosphorylation of IkappaBalpha by its kinase inhibitor of kappaB kinase alpha. Methimazole had no effect on NF-kappaB induction, demonstrating that drug potency correlated with the chemical reactivity of the thionamide-associated sulfur group. Taken together, our data demonstrate that thioureylenes with a common, heterocyclic structure inhibit inflammation and immune function via the NF-kappaB pathway. Our results may explain the observed remission of proinflammatory diseases upon antithyroid therapy in hyperthyroid patients. The use of related thioureylenes may provide a new therapeutic basis for the development and application of anti-inflammatory compounds.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
CarbimazoleThyroid peroxidaseProteinHumans
Yes
Inhibitor
Details