Hematoporphyrin derivative-mediated photodynamic therapy for human colon carcinoma: a comparative study with LoVo and CoLo205 cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the killing effect of photodynamic therapy (PDT) mediated by hematoporphyrin derivative (HpD) on human colon carcinoma LoVo and CoLo205 cells in vitro.</p><p><b>METHODS</b>LoVo and CoLo205 cells cultured in vitro were incubated in the presence of 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, and 4.0 microg/ml HpD for 4 h and exposed to different light doses delivered using a semiconductor laser at 630 nm with the energy density of 2, 5, 10, and 20 J/cm(2). After further culture for 24 h, the survival rate of LoVo and CoLo205 cells were analyzed by MTT assay, and the cellular fluorescence intensities of HpD were measured with a luminescence spectrometer.</p><p><b>RESULTS</b>HpD-PDT resulted in effective cell killing to a comparable magnitude in LoVo and CoLo205 cells cultured in vitro (P>0.05). The killing effects were positively correlated with the concentration of HpD and the dosage of laser irradiation. Exposure to 20 J/cm(2) resulted in an IC(50) of LoVo and CoLo205 cells of 0.4 and 0.6 microg/ml respectively, which were not significantly different (P>0.05). The cellular HpD fluorescence intensities were also similar between the two cells.</p><p><b>CONCLUSION</b>HpD-PDT may effectively kill LoVo and CoLo205 cells cultured in vitro.</p>

Experimental Study on the Effect of KangXin oral solution on brain mitochondrial DNA deletion mutation in aged Balb/c mice / 中华中医药杂志

Objective: To explore the effect of KangXin oral solution on brain mitochondrial DNA(mtDNA) deletion mutation in aged Balb/c mice.Methods: The Balb/c mice were divided into the young group(6weeks),middle-aged group(6months) and aged group(14 months),each group has 10 mice.Brain mtDNA were obtained and polymerase chain reaction(PCR) technique was used to examine the fragment deletion of brain mtDNA,thus,to confi rm there was deletion of mtDNA in aged mice,s brain.The aged Balb/c mice were divided into two groups: the aged blank control group being given 0.9% normal sodium,KangXin oral solution group.After being treated for four months,the brain mtDNA were obtained and polymerase chain reaction(PCR) technique was used to amplify wild-type and deletion from of mtDNA.Gel imaging meter was used to detect optical density,then,to compare the optical density ratios of deletion from mtDNA/ wide type mtDNA in two groups.Results: There were 304bp mtDNA deletion in brain mitochondrial of aged Balb/c mice,but same mtDNA deletions were not detected in brain mitochondrial of young and middle-aged mice.Compared with aged blank control group,the mtDNA deletion of aged Balb/c mice in KangXin oral solution group decreased obviously(P〈0.001).Conclusion: mtDNA deletion mutation accumulates with the increase of age.KangXin oral solution can inhibit mtDNA deletion of aged mice.