[ ABSTRACT] AIM:To observe the effect of the metabolites generated from oxidative deamination of methylamine ( MA) or benzylamine ( BZA ) catalyzed by semicarbazide-sensitive amine oxidase ( SSAO ) on 3T3-L1 adipocytes. METHODS:3T3-L1 preadipocytes were induced to differentiation.SSAO activity was determined by high performance liquid chromatography ( HPLC) at different differentiation time points.MTT assay was applied to detect cell vitality after exposure to different concentrations of MA or BZA.Fluorescence probe DCFH-DA was used to determine the production of reactive oxygen species after incubation of 3T3-L1 adipocytes with MA or BZA.After exposure to 0.5 mmol/L MA or BZA for 4 h, malondialdehyde ( MDA) , total superoxide dismutase ( T-SOD) and glutathione ( GSH) in the adipocytes or prea-dipocytes were measured.RESULTS:SSAO activity increased with the increase in the differentiation days, and reached a maximum at the 8th day.Incubation of the cells with different concentrations of MA or BZA for 4 h did not significantly de-creased the cell vitality (P>0.05).After exposure to 0.5 mmol/L MA or BZA, the reactive oxygen species in adipocytes significantly increased, and were about 3 to 4 times as compared with control group (P<0.05).After treatment with 0.5 mmol/L MA or BZA for 4 h, MDA content significantly increased, while the activity of SOD and the expression of GSH de-creased in mature adipocytes compared with control group (P<0.05).However, MDA, T-SOD and GSH did not change significantly after treatment with equal molar of MA or BZA in the preadipocytes ( P>0.05 ) .CONCLUSION: MA or BZA induces oxidative stress in the mature adipocytes, which might result from the deamination products catalyzed by SSAO.%目的：观察氨基脲敏感型胺氧化酶（SSAO）催化其底物甲胺（MA）和苯甲胺（BZA）的氧化脱氨反应对成熟3 T3-L1脂肪细胞的氧化应激作用。方法：3 T3-L1前脂肪细胞诱导分化为成熟脂肪细胞；高效液相色谱法检测不同分化天数下细胞SSAO活性的变化；MTT法检测不同浓度的MA或BZA对细胞活力的影响；荧光探针方法检测细胞在药物作用下产生的活性氧；以0.5 mmol／L MA或BZA处理成熟脂肪细胞或未经诱导分化的前脂肪细胞4 h，观察细胞产生的甲醛（ FA）、苯甲醛（ BZ）、脂质过氧化指标丙二醛（ MDA）、总超氧化物歧化酶（ T-SOD）和谷胱甘肽（ GSH）的变化。结果：SSAO活性随细胞分化天数的增加而增加，并于第8天达到高峰；不同浓度MA或BZA作用细胞4 h对细胞活力无显著影响（ P＞0.05）；0.5 mmol／L MA或BZA孵育后，细胞产生的活性氧增高，约为阴性对照组的3～4倍，差异有统计学意义（ P＜0.05）；在成熟脂肪细胞中，MDA的含量增加，而T-SOD和GSH的活性和含量减少，与阴性对照组相比，差别有统计学意义（ P＜0.05）；MA和BZA作用未经诱导分化的前脂肪细胞，其MDA和SOD和GSH的变化不明显，差别无统计学意义（ P＞0.05）。结论：SSAO可能通过其介导的氧化脱氨反应引起3 T3-L1成熟脂肪细胞产生氧化应激。
展开▼
