摘要
本文对用于光动力癌症疗法(PPT)的新光敏剂铝酞菁(AlSPC)与人癌细胞的作用进行了实验探讨。细胞荧光光谱的测定及荧光强度的定量表明,铝酞菁能被人癌细胞所吸收,且经40μg/mlAlSPC培育24小时后,细胞对AlSPC吸收的量级为3.47μg/10~7细胞。对人癌细胞的光敏杀伤显示,杀伤效果正比于光敏剂培育浓度与光辐照剂量。由脂质过氧化的荧光研究表明,经光敏反应后人癌细胞膜的脂质过氧化代谢产物丙二醛(MDA)明显增高,揭示在AlSPC光敏反应中有活性氧作用。色氨酸降解的荧光实验证实,在光敏反应中有单线态氧(~1O_2)的生成。
Photodynamic cancer therapy (PDT) is a hopeful means to tieat cancer. Instead of HPD, recently some new photosensitizers have been developed. A-mong them phthalocyanine (PC) are most noticed, because it is pure chemical, rather stable, and is absorbed more strongly in red region (the best penetration wave-band of human tissue) .After we synthesized sulfonated aluminum phthalocyanine (AlSPC) in our laboratory and found out its photokilling ability to human liver cancer line (SMMC-7721), the continuous study on photosensitization of SMMC-7721 cell line with AlSPC using fluorescence technic is reported in this paper.1.Cellular uptakeCells were incubated with AlSPC (40ng/ml) for 24h, then extracted by 1N NaOH. The cell plasma was measured by fluorescence spcctropholometer. ~ts 675nm fluorescence peak coincides with the peak of AlSPC watci solution. This convinces that SMMC-7721 cells can absorb the AlSPC. Through the calibration, the content of AlSPC entering the cell is about 3.9n mol/107 cells evel.The cell uptake and distribution were also studied by fluorescence microscope using 365nm excitation light. The fluorescence microphotograph of monolayer vering cells show that the red fluorescence is mainly in the cell cytoplasm, Mich directly revealed that AlSPC has entered cells.2.Photodamage of cellsThe damage of cells vs AlSPC incubating concentration and light irradiation flux was evaluated, the results show that the damaging degree of cells is proportional to the product of AlSPC concentration and light irradiation flux.In further study on the cells lipid peroxides (LPO), the experiment demonstrated that the metabolic production MDA of LPO in the group with AlSPC only and the group with light irradiation only was similar to the control group. But it was obviously higher when cells were incubated with 40ug/ml AlSPC for 24h and irradiated with red light. This result reflected that the photosensi-tization of cells enhanced the cell's lipid peroxidation, so as to damage the cells, and suggested that cell's lipid peroxidalion should be one of the damaging mechanisms in AlSPC photosensitization of cells. Besides, the cells lipid peroxidation is the oxidating result of active oxygen to cells, which also suggested there have been active oxygen intermediately produced in the photosensitization process.3.1O2 intermediate in photochemical reaction of AlSPCSinglet oxygen (1O2) intermediate in the photochemical reaction of AlSPC was Studied by Trytophan ( TrP ) photodegradation method, when AlSPC (40μg/ml) was added to the TrP water solution (9×10-3M), it was shown that the TrP photodegradation increased linearly with the irradiation flux by measuring the fluorescence intensity of TrP, reflecting that 1O2 was produced in the photochemical reaction. When sodium azide (NaN3) -the well-known 1O2 inhibitor was added to the reaction system, itt, protecting effect to TrP further comfirmed the existence of 1O2 during the reaction process.This corresponds with the afore-mentioned results of cells lipid peroxidation and also affords and explanation for it.
出处
《发光学报》
EI
CAS
CSCD
北大核心
1990年第1期49-54,共6页
Chinese Journal of Luminescence
