Objective Age-related diseases, including neurodegenerative diseases, are associated with oxidative stress and lipid peroxidation, and increase the levels of cholesterol auto-oxidation products such as 7β-hydroxychol...Objective Age-related diseases, including neurodegenerative diseases, are associated with oxidative stress and lipid peroxidation, and increase the levels of cholesterol auto-oxidation products such as 7β-hydroxycholesterol(7β-OHC). Thus, it is imperative to identify agents that can prevent 7β-OHC-induced side-effects. Methods We evaluated the potential protective effects of Carpobrotus edulis ethanol-water extract(EWe) on murine oligodendrocytes(158 N) cultured in the absence or presence of 7β-OHC(20 μg/mL, 24 h). The cells were incubated with EWe(20-200 μg/mL) 2 h before 7β-OHC treatment. Mitochondrial activity and cell growth were evaluated with the MTT assay. Photometric methods were used to analyze antioxidant enzyme [catalase(CAT) and glutathione peroxidase(GPx)] activities and the generation of lipid and protein oxidation products [malondialdehyde(MDA), conjugated diene(CD), and carbonylated proteins(CPs)]. Results Treatment with 7β-OHC induced cell death and oxidative stress(reflected by alteration in CAT and SOD activities). Overproduction of lipid peroxidation products(MDA and CDs) and CPs was also reported. The cytotoxic effects associated with 7β-OHC were attenuated by 160 μg/mL of EWe of C. edulis. Cell death induced by 7β-OHC treatment was ameliorated, GPx and CAT activities were restored to normal, and MDA, CD, and CP levels were reduced following C. edulis extract treatment. Conclusion These data demonstrate the protective activities of C. edulis EWe against 7β-OHC-induced disequilibrium in the redox status of 158 N cells, indicative of the potential role of this plant extract in the prevention of neurodegenerative diseases.展开更多
Amyloid peptide, the main component of senile plaques, is a major biological characteristic of Alzheimer’s disease (AD). The aim of the present study conducted on human neuronal SK-N-BE cells was to evaluate whether ...Amyloid peptide, the main component of senile plaques, is a major biological characteristic of Alzheimer’s disease (AD). The aim of the present study conducted on human neuronal SK-N-BE cells was to evaluate whether oligomerized Aβ1-40-induced cell damages was associated with lipid modifications. Under treatment with Aβ1-40 (10 - 100 μM;24 - 48 h), cell viability was recorded with the MTT test and by measuring LDH activity. Mitochondrial transmembrane potential and ATP production were assessed using flow cytometry and a luciferase-based ATP bioluminescence assay, respectively. Annexin V-CF647 staining assay for cell apoptosis detection was performed using flow cytometry. Potentially intracellular cytotoxic lipids (oxysterols: 7α-hydroxycholesterol (7α-OHC), 7β-hydroxycholesterol (7β-OHC), and 7-ketocholesterol (7KC), 24(S)-hydroxycholesterol;arachidonic acid (C20:4 n-6);VLCFAs (C22:0, C24:0, C24:6 and C26:0)) were measured using gas chromatography coupled with mass spectrometry. The cellular level of docosahexaenoic acid (C22:6 n-3), often altered in AD, was also quantified. In the presence of Aβ1-40, the percentage of MTT-positive cells decreased and was associated with an increase in LDH activity. In addition, treatment with oligomerized Aβ1-40 induced a decrease of mitochondrial transmembrane potential as well as an apoptotic cell death. Sterol analysis revealed a higher cholesterol level and a significant increase of cytotoxic oxysterols per cell (7KC + 7β-OHC), and of the [(7β-OHC + 7KC)/cholesterol] ratio, considered as a lipid peroxidation index, in Aβ1-40-treated cells. An enhancement of C20:4 n-6, C22:6 n-3 and saturated VLCFAs was also observed. Therefore, Aβ1-40-induced side effects are associated with intracellular accumulation of lipids, especially cholesterol, oxysterols (7β-OHC, 7KC), C20:4 n-6, and saturated VLCFAs, which could in turn contribute to neurotoxicity.展开更多
文摘Objective Age-related diseases, including neurodegenerative diseases, are associated with oxidative stress and lipid peroxidation, and increase the levels of cholesterol auto-oxidation products such as 7β-hydroxycholesterol(7β-OHC). Thus, it is imperative to identify agents that can prevent 7β-OHC-induced side-effects. Methods We evaluated the potential protective effects of Carpobrotus edulis ethanol-water extract(EWe) on murine oligodendrocytes(158 N) cultured in the absence or presence of 7β-OHC(20 μg/mL, 24 h). The cells were incubated with EWe(20-200 μg/mL) 2 h before 7β-OHC treatment. Mitochondrial activity and cell growth were evaluated with the MTT assay. Photometric methods were used to analyze antioxidant enzyme [catalase(CAT) and glutathione peroxidase(GPx)] activities and the generation of lipid and protein oxidation products [malondialdehyde(MDA), conjugated diene(CD), and carbonylated proteins(CPs)]. Results Treatment with 7β-OHC induced cell death and oxidative stress(reflected by alteration in CAT and SOD activities). Overproduction of lipid peroxidation products(MDA and CDs) and CPs was also reported. The cytotoxic effects associated with 7β-OHC were attenuated by 160 μg/mL of EWe of C. edulis. Cell death induced by 7β-OHC treatment was ameliorated, GPx and CAT activities were restored to normal, and MDA, CD, and CP levels were reduced following C. edulis extract treatment. Conclusion These data demonstrate the protective activities of C. edulis EWe against 7β-OHC-induced disequilibrium in the redox status of 158 N cells, indicative of the potential role of this plant extract in the prevention of neurodegenerative diseases.
文摘Amyloid peptide, the main component of senile plaques, is a major biological characteristic of Alzheimer’s disease (AD). The aim of the present study conducted on human neuronal SK-N-BE cells was to evaluate whether oligomerized Aβ1-40-induced cell damages was associated with lipid modifications. Under treatment with Aβ1-40 (10 - 100 μM;24 - 48 h), cell viability was recorded with the MTT test and by measuring LDH activity. Mitochondrial transmembrane potential and ATP production were assessed using flow cytometry and a luciferase-based ATP bioluminescence assay, respectively. Annexin V-CF647 staining assay for cell apoptosis detection was performed using flow cytometry. Potentially intracellular cytotoxic lipids (oxysterols: 7α-hydroxycholesterol (7α-OHC), 7β-hydroxycholesterol (7β-OHC), and 7-ketocholesterol (7KC), 24(S)-hydroxycholesterol;arachidonic acid (C20:4 n-6);VLCFAs (C22:0, C24:0, C24:6 and C26:0)) were measured using gas chromatography coupled with mass spectrometry. The cellular level of docosahexaenoic acid (C22:6 n-3), often altered in AD, was also quantified. In the presence of Aβ1-40, the percentage of MTT-positive cells decreased and was associated with an increase in LDH activity. In addition, treatment with oligomerized Aβ1-40 induced a decrease of mitochondrial transmembrane potential as well as an apoptotic cell death. Sterol analysis revealed a higher cholesterol level and a significant increase of cytotoxic oxysterols per cell (7KC + 7β-OHC), and of the [(7β-OHC + 7KC)/cholesterol] ratio, considered as a lipid peroxidation index, in Aβ1-40-treated cells. An enhancement of C20:4 n-6, C22:6 n-3 and saturated VLCFAs was also observed. Therefore, Aβ1-40-induced side effects are associated with intracellular accumulation of lipids, especially cholesterol, oxysterols (7β-OHC, 7KC), C20:4 n-6, and saturated VLCFAs, which could in turn contribute to neurotoxicity.
