【摘要】 用不同浓度的外源抗坏血酸(ASA)对BY-2烟草悬浮细胞进行处理,测定了细胞中可溶性蛋白质含量、脂质过氧化产物丙二醛(MDA)含量、相对电解质渗透率、超氧化物歧化酶(SOD)活性、抗坏血酸(ASA)含量和还原型谷胱甘肽(GSH)含量等生理生化指标,从细胞脂质过氧化及抗氧化功能的角度探讨了不同浓度抗坏血酸对BY-2烟草悬浮细胞生长及衰老的影响。结果表明,当用2mmol.L-1 ASA处理时,能促进细胞分裂生长,增加可溶性蛋白产量,减少膜透性和MDA含量,维持SOD活性和ASA与GSH含量在较高水平,说明ASA对促进细胞生长,维持细胞抗氧化功能以延缓细胞衰老方面起着重要作用。但当ASA浓度过高,超出4mmol.L-1时则对细胞造成伤害,MDA含量和膜透性增加,SOD活性降低,ASA和GSH含量呈现先升后降的趋势。更多还原

【Abstract】 The free radical theory of aging states that aging results from the accumulated damage caused by free radicals which induce oxidative stress.Ascorbic acid(ASA) is ubiquitous and fundamental in living cells,where it acts as a water-soluble antioxidant with significant capacity of scavenging O2-· and H2O2.To evaluate the effects of exogenous ASA on growth and senescence of tobacco BY-2 suspension cells,the content of soluble protein and antioxidant parameters in cells cultured in five KCMS liquid medium groups with 0,2,4,8 and 16 mmol·L-1 ASA,respectively.Cells were assayed for glutathione(GSH),ASA,activities of superoxide dismutase(SOD),protein,malondialdehyde(MDA) and electrolyte leakage.Under the treatment of 2 mmol·L-1 ASA,the soluble protein content in cells was higher than that in other groups,indicating that cells cultured in KCMS medium containing 2 mmol·L-1 ASA grew more rapidly than the control group.In addition,the contents of ASA,GSH and SOD activity all increased,while the MDA content and electrolyte leakage decreased compared with the control group.However,when ASA concentration was over 4 mmol·L-1,the growth of the cells was inhibited;ASA and GSH contents came to the maximal values after treated 2 days and 6 days respectively,and then decreased;SOD activity decreased and the MDA content and electrolyte leakage increased compared with the control.We concluded that appropriate concentrations of ASA could accelerate cell growth and retard senescence in tobacco BY-2 suspension cells.更多还原