RESUMO
OBJECTIVE: To evaluate the cytotoxicity of cucurbitacin B solid lipid nanoparticles (SLN) on human neuroblastoma SK-N-SH cell line in vitro. METHODS: The SK-N-SH cell line was treated with cucurbitacin B SLN at various concentrations. Growth suppression was evaluated by MTT method; apoptosis related alterations in morphology were ascertained under light microscopy. Flow cytometry (FCM) was used to investigate the distribution of cell life. RESULTS: Free cucurbitacin B and cucurbitacin B SLN inhibited the growth of SK-N-SH cells after 48 h treatment in a dose dependent manner, with IC50 values of 0.508 and 12.6 μmol · L-1, respectively. The apoptotic rates at concentrations of 0.143 and 0.716 μmol · L-1 were (34.9 ± 4.6)% and(53.6 ± 6.3)%, respectively, all of which were significantly higher than that of free cucurbitacin B (13.2 ± 2.3)% and(43.4 ± 5.5)% (P < 0.05), respectively. Under microscopy, the cells treated with free cucurbitacin B and cucurbitacin B SLN exhibited characteristics of apoptosis including decreased cell density of groups, reduced cell volume, and changed form of majority cell. Flow cytometry analysis suggested that free cucurbitacin B retarded the progression of cell cycle at G2/M and S phase, and cucurbitacin B SLN retarded the progression of cell cycle at G2/M phase. CONCLUSION: Cucurbitacin B can not only inhibit the proliferation but also induce apoptosis of human neuroblastoma SK-N-SH cell line, demonsting strong cytotoxicity. Cytotoxicity of cucurbitacin B SLN is higher than that of free cucurbitacin B.
RESUMO
Aim To explore the effects and mechanism of ginsenoside-Rg1 on SK-N-SH cells treated with chronic morphine and naloxone-precipitated withdrawal. Methods Cells were pretreated with ginsenoside-Rg1 1,2,4,8,16,32 ?mol?L-1 for 24 h,then incubated for 24 h with morphine ( 100 ?mol?L-1 ) . MTT colorimetr was used to study the effects of ginsenoside-Rg1 on the multiplication of the cells treated with chro-nic morphine. After stimulated by the same concentra-tion of morphine,cells were added with different concentrations of Rg1 1,2,4 ?mol?L -1 for 24 h before stimulated with 10 ?mol?L -1 NAL. Fuorospectrophotometry RT-PCR and Western blot techniques were used to detect the effects of ginsenoside-Rg1 on the [Ca2+ ]i,CaMKⅡ ? mRNA and protein expression of the SK-N-SH cells treated with chronic morphine and naloxone-precipitated withdrawal. Results ① Compared with control group,morphine significantly inhibited cell multiplication and resulted in calcium overload,and the expression of CaMKⅡ-? mRNA and protein noticeably increased ( P