The fungal metabolite, citrinin, inhibits lipopolysaccharide/interferon-γ-induced nitric oxide production in glomerular mesangial cells

• Published in: International immunopharmacology Vol. 10; no. 12; pp. 1608 - 1615
• Main Authors: Liu, Biing-Hui, Chi, Jhih-Ying, Hsiao, Yu-Wei, Tsai, Kuen-Daw, Lee, Yi-Ju, Lin, Chia-Ching, Hsu, Shu-Ching, Yang, Shu-Mei, Lin, Ting-Hui
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 01.12.2010; Elsevier
• Subjects: Animals; Biological and medical sciences; Blotting, Western; Cell Line; Cell Nucleus - drug effects; Cell Nucleus - enzymology; Cell Nucleus - immunology; Cell Nucleus - metabolism; Cell Survival - drug effects; Citrinin; Citrinin - isolation & purification; Citrinin - pharmacology; Cytosol - drug effects; Cytosol - enzymology; Cytosol - immunology; Cytosol - metabolism; Data processing; Electrophoretic Mobility Shift Assay; gamma -Interferon; Gene expression; Gene Expression - drug effects; Immune response; Immunologic Factors - isolation & purification; Immunologic Factors - pharmacology; Immunomodulation; Inflammation; iNOS; Interferon regulatory factor 1; Interferon-gamma - pharmacology; Lipopolysaccharides; Lipopolysaccharides - pharmacology; Medical sciences; MES-13 cells; Mesangial cells; Mesangial Cells - drug effects; Mesangial Cells - immunology; Mesangial Cells - metabolism; Metabolites; Mice; Monascus; Monascus - metabolism; Mycotoxins; NF- Kappa B protein; NF-κB; Nitric oxide; Nitric Oxide - antagonists & inhibitors; Nitric Oxide - biosynthesis; Nitric Oxide Synthase Type II - antagonists & inhibitors; Nitric Oxide Synthase Type II - genetics; Nitric-oxide synthase; Nuclear transport; Pharmacology. Drug treatments; Phosphorylation; Reverse Transcriptase Polymerase Chain Reaction; Secondary metabolites; Signal transduction; STAT-1α; Transcription; NO; IκB-α; Citrinin; IRF-1; MTT; LPS; STAT-1α; NF-κB; IFN-γ; γ-IRE; EMSA; Stx; iNOS; TBS; HUS; qRT-PCR; IKK; TBST; IL-1β; PAA; TNF-α; JAK; Nitric oxide; GAS; MES-13 cells; PVDF membrane; CTN; GAPDH; TLR4; Enzyme; Mesangial cell; Metabolite; NF-kB; Biosynthesis; In vitro; Kidney; Nitric-oxide synthase; Renal glomerulus; Signal transduction; Antibiotic; Urinary system; Production; Lipopolysaccharide; Inhibitor; Oxidoreductases; Transcription factor NFκB; Transduction factor STAT; Gamma interferon
• ISSN: 1567-5769; 1878-1705; 1878-1705
• DOI: 10.1016/j.intimp.2010.09.017

The mycotoxin, citrinin (CTN), is a secondary metabolite of the fermented products of Monascus. The mycotoxin can either suppress or stimulate immune responses. In the present study, the immunomodulatory role of CTN in nitric oxide (NO) production, a proinflammatory mediator in the process of inflammation, was investigated. NO is well known as a mediator of immune responses. Overproduction of NO catalyzed by inducible nitric oxide synthase (iNOS) protects host cells against microbial invasion, while aberrant iNOS induction is associated with the pathophysiology of inflammatory events. Herein, we report that CTN significantly suppressed lipopolysaccharide (LPS)/interferon (IFN)-γ-induced NO production in MES-13 cells, a glomerular mesangial cell line. The percentage of NO reduction caused by CTN was far greater than that of the decline in cell viability. CTN decreased iNOS gene and protein expressions in concentration-dependent manners. CTN caused declines in LPS/IFN-γ-induced signal transducer and activator of transcription-1α (STAT-1α) phosphorylation. Furthermore, LPS/IFN-γ's induction of interferon response factor-1 (IRF-1) mRNA expression was inhibited by CTN. Moreover, CTN attenuated IκB-α phosphorylation and reduced NF-κB's translocation to the nuclear fraction. Taken together, our data indicated that CTN significantly suppressed NO and iNOS expressions in MES-13 cells via inhibition of the JAK/STAT-1α and NF-κB signaling pathways. ►The mycotoxin, citrinin (CTN), suppressed lipopolysaccharide (LPS)/interferon (IFN)-?-induced nitric oxide (NO) production in MES-13 cells, a glomerular mesangial cell line. ►The inhibitory effect of CTN on LPS/IFN-?-stimulated NO production was not due to a decrease in MES-13 cell viability but was caused by suppression of inducible nitric oxide synthase (iNOS) gene and protein expressions. ►CTN significantly suppressed NO and iNOS expressions in MES-13 cells via inhibition of the JAK/STAT-1α and NF-αB signaling pathways.