Objective To generate eukaryotic expression vector of siRNA specific for β-site APP cleaving enzyme(BACE),and detect the interfering effect to the expression of BACE. Methods To clone the BACE targeting siRNA gene by...Objective To generate eukaryotic expression vector of siRNA specific for β-site APP cleaving enzyme(BACE),and detect the interfering effect to the expression of BACE. Methods To clone the BACE targeting siRNA gene by PCR, the PCR products was inserted into the pUC19/EGFP-U6 plasmid. Then it was sub-cloned into the vector named pLXSN. The resultant plasmid was named pLXSN/EGFP-U6-siBACE, it was packaged into AmphoPack-293 cells by calcium phosphate transfection and collected the virus supernatant. The neuroblastoma cells SK-N-SH was infected with the pLXSN/EGFP-U6-siBACE retroviral vector, immunohistochemistry method was used to detect whether the pLXSN/EGFP-U6-siBACE infection can inhibit the expression of BACE of the neuroblastoma cells. Results The pLXSN/EGFP-U6-siBACE retroviral vector was constructed successfully and the siBACE can inhibit the BACE of the neuroblastma effectively. Conclusion The siRNA can inhibit the expression of the BACE gene, the endogenous production of BACE protein was decreased. It will lay the important foundation for using RNA technology to prevent the Alzheimer's disease.展开更多
Several studies have demonstrated that the amount of beta-amyloid (Aβ) protein in the brain can be lowered by down-regulating Aβ production, promoting Aβ degradation, reducing Aβ oligomerization or deposition, ...Several studies have demonstrated that the amount of beta-amyloid (Aβ) protein in the brain can be lowered by down-regulating Aβ production, promoting Aβ degradation, reducing Aβ oligomerization or deposition, thereby alleviating symptoms of Alzheimer's disease. Curcumin has been known to be a peroxisome proliferator activated receptor gamma (PPARy) agonist and can obviously inhibit Aβ production and oligomerization. This study investigated the effects of curcumin on the G-site APP cleaving enzyme 1 (BACE1) activity and PPARy expression in human neuroblastoma SH-SY5Y cells, and validated the inhibitory effects of curcumin on Aβ40/42 expression in the brain. Results revealed that PPARy mRNA and protein expression in the human neuroblastoma SH-SY5Y cells significantly increased with increasing curcumin concentration and time course (P 〈 0.05); BACE1 mRNA and protein expression and Aβ40/42 production significantly decreased with increasing curcumin concentration and time course (P 〈 0.05). The changes in PPARy and BACE1 expression during Aβ production could be reversed by the PPARy antagonist GW9662. These findings indicate that curcumin reduced Aβ production by activating PPARy expression and inhibiting BACE1 expression in a concentration- and time-dependent manner.展开更多
文摘Objective To generate eukaryotic expression vector of siRNA specific for β-site APP cleaving enzyme(BACE),and detect the interfering effect to the expression of BACE. Methods To clone the BACE targeting siRNA gene by PCR, the PCR products was inserted into the pUC19/EGFP-U6 plasmid. Then it was sub-cloned into the vector named pLXSN. The resultant plasmid was named pLXSN/EGFP-U6-siBACE, it was packaged into AmphoPack-293 cells by calcium phosphate transfection and collected the virus supernatant. The neuroblastoma cells SK-N-SH was infected with the pLXSN/EGFP-U6-siBACE retroviral vector, immunohistochemistry method was used to detect whether the pLXSN/EGFP-U6-siBACE infection can inhibit the expression of BACE of the neuroblastoma cells. Results The pLXSN/EGFP-U6-siBACE retroviral vector was constructed successfully and the siBACE can inhibit the BACE of the neuroblastma effectively. Conclusion The siRNA can inhibit the expression of the BACE gene, the endogenous production of BACE protein was decreased. It will lay the important foundation for using RNA technology to prevent the Alzheimer's disease.
基金the National Natural Science Foundation of China,No.30600196the Science Foundation of Chongqing,No.2006BB5042the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry,No.[2007]1108
文摘Several studies have demonstrated that the amount of beta-amyloid (Aβ) protein in the brain can be lowered by down-regulating Aβ production, promoting Aβ degradation, reducing Aβ oligomerization or deposition, thereby alleviating symptoms of Alzheimer's disease. Curcumin has been known to be a peroxisome proliferator activated receptor gamma (PPARy) agonist and can obviously inhibit Aβ production and oligomerization. This study investigated the effects of curcumin on the G-site APP cleaving enzyme 1 (BACE1) activity and PPARy expression in human neuroblastoma SH-SY5Y cells, and validated the inhibitory effects of curcumin on Aβ40/42 expression in the brain. Results revealed that PPARy mRNA and protein expression in the human neuroblastoma SH-SY5Y cells significantly increased with increasing curcumin concentration and time course (P 〈 0.05); BACE1 mRNA and protein expression and Aβ40/42 production significantly decreased with increasing curcumin concentration and time course (P 〈 0.05). The changes in PPARy and BACE1 expression during Aβ production could be reversed by the PPARy antagonist GW9662. These findings indicate that curcumin reduced Aβ production by activating PPARy expression and inhibiting BACE1 expression in a concentration- and time-dependent manner.