Modulators of Sphingolipid Metabolism Reduce Lung Inflammation

Abstract

The investigation of novel targets for the treatment of cystic fibrosis (CF) lung inflammation is a major priority, considering that no effective therapy is available for this purpose. Consistent with the evidence that the sphingolipid (SL) ceramide regulates airway inflammation and infection in mice and patients with CF, SLs were identified as targets for treating pulmonary disorders, including CF. Because miglustat, an inhibitor of the synthesis of glycosphingolipids, reduces the Pseudomonas aeruginosa-dependent transcription of the IL-8 gene in bronchial cells, we examined the effects of miglustat and amitriptyline, another drug affecting ceramide metabolism, on the expression of 92 genes implicated in host immune defense. Infection with the P. aeruginosa strain PAO1 up-modulated the expression of 14 (27%) genes in IB3-1 cells and 15 (29%) genes in CF primary respiratory epithelia grown at an air-liquid interface, including chemokines (IL-8, growth-regulated Gro-α/β/γ proteins, and granulocyte chemotactic peptide-2 [GCP-2]), proinflammatory cytokines (IL-1α/β, IL-6, and TNF-α), and the intercellular adhesion molecule-1, nuclear factor kB1, toll like receptor 2, and human defensin B4 genes, confirming that bronchial epithelium is an important source of inflammatory mediators. Both miglustat and amitriptyline reduced the immune response, an effect that paralleled a decrease in the P. aeruginosa-induced accumulation of ceramide. Miglustat (100 mg/kg), given to C57BL/6 mice once daily for a period of 3 consecutive days before lipopolysaccharide (LPS) challenge, strongly reduced the number of neutrophils recruited in the airways and the expression of the keratinocyte-derived chemokine in lung extracts. Collectively, these results indicate that targeting the metabolism of SLs can down-modulate the recruitment of neutrophils into the lung.

De novo ceramide synthesis is involved in acute inflammation during labor

“…Nuclease free water was then applied to the membrane to elute the RNA, stored at -80°C until used. The amplification of target genes (IL-6, TNF-α, SPTLC 1, SPTLC 2, SPTLC 3: primer sequences as previously reported (Hornemann et al, 2006;Dechecchi et al, 2011) was performed using the Syber Green system (Qiagen, Milan, Italy). Relative mRNA expression of target genes was normalized to the endogenous GAPDH control gene and results calculated by 2 -ΔΔCt method (Arocho et al, 2006), as labored vs. control cesarean placentas.…”

Pharmacological Modulators of Sphingolipid Metabolism for the Treatment of Cystic Fibrosis Lung Inflammation

“…Extending our previous study (Dechecchi, 2008), we have recently demonstrated that the iminosugar N-butyldeoxynojirimycin (miglustat), an inhibitor of the first step in glycosphingolipid (GSL) biosynthesis, reducing the P.aeruginosa induced immunoreactive ceramide expression, produces an anti-inflammatory effect in human bronchial epithelial cells in vitro and down-regulates the neutrophil chemotaxis in murine lungs in vivo (Dechecchi, 2011). These findings strengthen the notion that the metabolism of SLs can be manipulated as a therapeutic option for CF lung disease.…”

“…Therefore cultured CF bronchial cells provide a useful tool for the pre-clinical testing of novel pharmacotherapies. Indeed, miglustat has an anti-inflammatory effect in CF bronchial cells, since it reduces the expression of key genes induced by P.aeruginosa and IL-8 protein release (Dechecchi, 2011). Also amitriptyline has an anti-inflammatory effect in CF bronchial cell lines ( Figure 5A) and at lower extent in CF primary cells ( Figure 5B).…”

“…Interestingly, we have recently demonstrated that, besides inhibiting IL-8 transcription, both miglustat and amitriptyline reduce the P.aeruginosa induced immunoreactive ceramide expression (Dechecchi, 2011), by targeting different pathways of SL metabolism: CerGlcT and/or nonlysosomal glucosylceramidase (miglustat) and ASM (amitriptyline). As far as the effect on immune response is concerned, the same overall decrease of ceramide could regulate the transmembrane signaling between the receptors for pathogens and the transcription of the inflammatory genes, thus reducing inflammation.…”

“…These findings strengthen the notion that the metabolism of SLs can be manipulated as a therapeutic option for CF lung disease. With regard to new treatments for CF lung pathology, miglustat deserves great attention since it restores CFTR function in respiratory and pancreatic cells in vitro (Norez, 2006;Dechecchi, 2008) and in CF mice (Lubamba, 2009) and produces an anti-inflammatory effect in vitro and in vivo (Dechecchi, 2011). Notably, miglustat is a FDAapproved and EMA−designated orally bioavailable orphan drug, used in Europe and USA for the treatment of Gaucher disease and other GSL storage diseases.…”