Takano M, Okuda M, Yasuhara M, Hori R
Department of Pharmacy, Kyoto University Hospital, Faculty of Medicine, Japan.
Pharm Res. 1994 May;11(5):609-15. doi: 10.1023/a:1018999423464.
The effects of gentamicin and G418 on the cellular function of LLC-PK1 epithelial pig kidney cells were investigated. Exposing the cells for 2 days to these aminoglycoside antibiotics inhibited the increase in cell-associated apical membrane enzyme activity (alkaline phosphatase, aminopeptidase, and gamma-glutamyltransferase). Kinetic analysis revealed that the maximal activity of alkaline phosphatase was reduced by these aminoglycosides. Both aminoglycosides inhibited [3H]leucine incorporation into microsomes prepared from LLC-PK1 cells. The LLC-PK1 cells transfected with DNA encoding aminoglycoside 3'-phosphotransferase II, designated T2000B, were resistant to G418 as assessed by colony formation assay and the number of floating dead cells and by assay of apical enzyme activity. After a 4-hr exposure to G418, [3H]leucine incorporation in the host LLC-PK1 cells was inhibited, whereas that in T2000B cells was relatively unaffected. Gentamicin inhibited [3H]leucine incorporation similarly in both cells. The inhibition of protein synthesis by aminoglycosides occurred earlier than that of apical enzyme activity. These findings suggest that the inhibition of protein synthesis by aminoglycoside antibiotics is a possible cause of the reduction in cell viability as well as the apical enzymes in LLC-PK1 cells.
研究了庆大霉素和G418对猪肾LLC-PK1上皮细胞细胞功能的影响。将这些细胞暴露于这些氨基糖苷类抗生素2天，抑制了细胞相关顶膜酶活性（碱性磷酸酶、氨肽酶和γ-谷氨酰转移酶）的增加。动力学分析表明，这些氨基糖苷类药物降低了碱性磷酸酶的最大活性。两种氨基糖苷类药物均抑制[3H]亮氨酸掺入从LLC-PK1细胞制备的微粒体中。通过集落形成试验、漂浮死细胞数量以及顶酶活性测定评估，用编码氨基糖苷3'-磷酸转移酶II的DNA转染的LLC-PK1细胞（命名为T2000B）对G418具有抗性。暴露于G418 4小时后，宿主LLC-PK1细胞中的[3H]亮氨酸掺入受到抑制，而T2000B细胞中的掺入相对未受影响。庆大霉素对两种细胞中[3H]亮氨酸掺入的抑制作用相似。氨基糖苷类药物对蛋白质合成的抑制作用早于对顶酶活性的抑制作用。这些发现表明，氨基糖苷类抗生素对蛋白质合成的抑制可能是LLC-PK1细胞活力降低以及顶酶减少的一个原因。
