Leuzzi Rosanna, Bánhegyi Gábor, Kardon Tamás, Marcolongo Paola, Capecchi Piero-Leopoldo, Burger Hans-Joerg, Benedetti Angelo, Fulceri Rosella
Dipartimento di Fisiopatologia e Medicina Sperimentale and Istituto di Semeiotica Medica, Università di Siena, Siena, Italy.
Blood. 2003 Mar 15;101(6):2381-7. doi: 10.1182/blood-2002-08-2576. Epub 2002 Nov 7.
Mutations in the gene of the hepatic glucose-6-phosphate transporter cause glycogen storage disease type 1b. In this disease, the altered glucose homeostasis and liver functions are accompanied by an impairment of neutrophils/monocytes. However, neither the existence of a microsomal glucose-6-phosphate transport, nor the connection between its defect and cell dysfunction has been demonstrated in neutrophils/monocytes. In this study we have characterized the microsomal glucose-6-phosphate transport of human neutrophils and differentiated HL-60 cells. The transport of glucose-6-phosphate was sensitive to the chlorogenic acid derivative S3483, N-ethylmaleimide, and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid, known inhibitors of the hepatic microsomal glucose-6-phosphate transporter. A glucose-6-phosphate uptake was also present in microsomes from undifferentiated HL-60 and Jurkat cells, but it was insensitive to S3483. The treatment with S3484 of intact human neutrophils and differentiated HL-60 cells mimicked some leukocyte defects of glycogen storage disease type 1b patients (ie, the drug inhibited phorbol myristate acetate-induced superoxide anion production and reduced the size of endoplasmic reticulum Ca(2+) stores). Importantly, the treatment with S3484 also resulted in apoptosis of human neutrophils and differentiated HL-60 cells, while undifferentiated HL-60 and Jurkat cells were unaffected by the drug. The proapoptotic effect of S3483 was prevented by the inhibition of nicotinamide adenine dinucleotide phosphate oxidase or by antioxidant treatment. These results suggest that microsomal glucose-6-phosphate transport has a role in the antioxidant protection of neutrophils, and that the genetic defect of the transporter leads to the impairment of cellular functions and apoptosis.
肝脏葡萄糖-6-磷酸转运蛋白基因的突变会导致1b型糖原贮积病。在这种疾病中，葡萄糖稳态和肝功能的改变伴随着中性粒细胞/单核细胞功能的损害。然而，在中性粒细胞/单核细胞中，微粒体葡萄糖-6-磷酸转运的存在及其缺陷与细胞功能障碍之间的联系均未得到证实。在本研究中，我们对人中性粒细胞和分化的HL-60细胞的微粒体葡萄糖-6-磷酸转运进行了表征。葡萄糖-6-磷酸的转运对绿原酸衍生物S3483、N-乙基马来酰亚胺和4,4'-二异硫氰基芪-2,2'-二磺酸敏感，这些都是已知的肝脏微粒体葡萄糖-6-磷酸转运蛋白的抑制剂。未分化的HL-60和Jurkat细胞的微粒体中也存在葡萄糖-6-磷酸摄取，但对S3483不敏感。用S3484处理完整的人中性粒细胞和分化的HL-60细胞可模拟1b型糖原贮积病患者的一些白细胞缺陷（即该药物抑制佛波酯诱导的超氧阴离子产生并减小内质网Ca(2+)储存的大小）。重要的是，用S3484处理还导致人中性粒细胞和分化的HL-60细胞凋亡，而未分化的HL-60和Jurkat细胞不受该药物影响。S3483的促凋亡作用可通过抑制烟酰胺腺嘌呤二核苷酸磷酸氧化酶或抗氧化处理来预防。这些结果表明，微粒体葡萄糖-6-磷酸转运在中性粒细胞的抗氧化保护中起作用，并且转运蛋白的遗传缺陷导致细胞功能受损和凋亡。
