Department of Lipidomics, Faculty of Medicine, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, Japan.
Biochem Biophys Res Commun. 2013 Jun 28;436(2):306-12. doi: 10.1016/j.bbrc.2013.05.099. Epub 2013 Jun 4.
Alkylglycerol monooxygenase (AGMO, glyceryl ether monooxygenase) is an enzyme known to catalyze the cleavage of the O-alkyl bond of glyceryl ether lipids. Identification of the gene encoding AGMO was reported recently, however, the involvement of AGMO in modulating cellular lipids has not been reported until now. In this report, we investigate a possible role for AGMO in macrophage platelet-activating factor (PAF) production. AGMO mRNA expression levels decreased with lipopolysaccharide (LPS) treatments in mouse peritoneal macrophages and RAW264.7 cells. Tetrahydrobiopterin-dependent conversion of lyso-PAF to glycerophosphocholine in the microsomal fraction was also reduced in LPS-treated RAW264.7 cells. In the LPS-treated cells, both lyso-PAF and PAF levels increased. Moreover, exogenously expressed AGMO caused a reduction in cellular lyso-PAF and PAF levels in HEK293 cells. Collectively, our results suggest a possible mechanism for AGMO in modulating macrophage PAF production by regulating cellular lyso-PAF levels.
烷基甘油单加氧酶 (AGMO，甘油醚单加氧酶) 是一种已知能够催化甘油醚脂质的 O-烷基键断裂的酶。最近报道了编码 AGMO 的基因的鉴定，但直到现在，AGMO 在调节细胞脂质中的作用尚未被报道。在本报告中，我们研究了 AGMO 在巨噬细胞血小板激活因子 (PAF) 产生中的可能作用。AGMO mRNA 表达水平随着脂多糖 (LPS) 处理而降低在小鼠腹腔巨噬细胞和 RAW264.7 细胞中。LPS 处理的 RAW264.7 细胞中，微粒体部分中溶酶体 PAF 向甘油磷酸胆碱的四氢生物蝶呤依赖性转化也减少了。在 LPS 处理的细胞中，溶酶体 PAF 和 PAF 的水平都增加了。此外，外源性表达的 AGMO 导致 HEK293 细胞中细胞内溶酶体 PAF 和 PAF 水平降低。综上所述，我们的结果表明 AGMO 通过调节细胞内溶酶体 PAF 水平来调节巨噬细胞 PAF 产生的可能机制。
