Inhibitors of ATP-binding cassette transporters suppress interleukin-12 p40 production and major histocompatibility complex II up-regulation in macrophages.
ATP-binding cassette (ABC) transporters are a large family of proteins whose role is to translocate various substances across biological membranes. They include the Tangier disease protein ABC1, sulfonylurea receptors (SUR), multidrug resistance protein (MDR), and cystic fibrosis transmembrane regulator (CFTR). In the current study, we investigated the involvement of ABC transporters in the regulation of lipopolysaccharide (LPS) and/or interferon (IFN)-gamma-induced interleukin (IL)-12 p40 and tumor necrosis factor (TNF)-alpha production, nitric oxide formation, as well as major histocompatibility complex II up-regulation in macrophages. The general ABC transporter inhibitor glibenclamide suppressed both IL-12 p40 and nitric oxide production. However, glibenclamide failed to affect the production of TNF-alpha. The selective ABC1 inhibitors 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid and sulfobromophthalein mimicked the suppressive effect of glibenclamide on IL-12 p40 production. On the other hand, both the MDR inhibitor verapamil and CFTR blocker 2,2'-iminodibenzoic acid failed to suppress the production of IL-12 p40. Furthermore, selective inhibitors and activators of SURs were without effect. In agreement with the pharmacological data, macrophages expressed mRNA for ABC1, but not SURs or CFTR. Intracellular levels of IL-12 p40 were decreased by glibenclamide, suggesting that glibenclamide does not affect IL-12 p40 secretion. The effect of glibenclamide did not involve an interference with the activation of the p38 and p42/44 mitogen-activated protein kinases or c-Jun kinase. Glibenclamide also suppressed IFN-gamma-induced up-regulation of major histocompatibility complex II. Taken together, our results indicate that ABC proteins regulate LPS and/or IFN-gamma-induced macrophage activation.
Haskó
György
G
Department of Surgery, University of Medicine and Dentistry-New Jersey Medical School, Newark, New Jersey 07103, USA. haskoge@umdnj.edu
Deitch
Edwin A
EA
Németh
Zoltán H
ZH
Kuhel
David G
DG
Szabó
Csaba
C
D018528:ATP-Binding Cassette Transporters / Q000037:antagonists & inhibitors*; D000818:Animals; D015153:Blotting, Western; D005434:Flow Cytometry; D005802:Genes, MHC Class II / Q000187:drug effects*; D005905:Glyburide / Q000494:pharmacology; D007004:Hypoglycemic Agents / Q000494:pharmacology; D018664:Interleukin-12 / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis; D012313:RNA / Q000096:biosynthesis / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013864:Thioglycolates / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D015854:Up-Regulation / Q000187:drug effects*
D018528:ATP-Binding Cassette Transporters; D007004:Hypoglycemic Agents; D013864:Thioglycolates; D014409:Tumor Necrosis Factor-alpha; D018664:Interleukin-12; D009569:Nitric Oxide; D012313:RNA; D005905:Glyburide