OBJECTIVE The greatest challenge in chemotherapy of ischemic stroke is the construction a suitable delivery system to overcome the poor physicochemical properties of drug and its low permeability across the blood brai...OBJECTIVE The greatest challenge in chemotherapy of ischemic stroke is the construction a suitable delivery system to overcome the poor physicochemical properties of drug and its low permeability across the blood brain barrier(BBB).METHODS In the present study,dendrimer,polyamidoamine(PAMAM),was synthesized as the nano-drug carriers.Angiopep-2,which has been proved excellent ability to cross the BBB,was exploited as the targeting ligand to conjugate PAMAM via bifunctional polyethylene glycol(PEG).Then scutellarin(STA)was encapsulated into the functionalized nanoparticles(NPs)to formulate Angiopep-2 modified STA-loaded PEG-PAMAM NPs.Ischemic stroke model was established to evaluate the treatment efficacy and protective mechanism of Angiopep-2-STA-PEG-PAMAM NPs.RESULTS The pharmacokinetics and biodistribu-tion demonstrated that Angiopep-2-STA-PEG-PAMAM NPs exhibited significantly higher plasma concentration from 1 h to 10 h after intravenous administration and improve accumulation in brain(4.7-fold)compared with STA solution.Moreover,prolonged elimination half-life(4.8-fold)and lower clearance(3.4-fold)were observed.The brain uptake study of 6-coumarin confirmed that Angiopep-2-PEG-PAMAM NPs possessed better brain targeting efficacy(3.2-fold)than PEG-PAMAM NPs.Angiopep-2-STA-PEG-PAMAM NPs obviously ameliorated infarct volume,neurological deficit,histopathological severity and neuronal apoptosis.In addition,Angiopep-2-STA-PEG-PAMAM NPs markedly inhibited the calcium content and the levels of IL-12p40,IL-13,IL-17 and IL-23.Furthermore,Angiopep-2-STA-PEG-PAMAM NPs significantly decreased the m RNA and protein expressions of HMGB1,TLR2,TLR4,TLR5,My D88,TRIF,TRAM,IRAK-4,TRAF6,IкBα,IKKβand NF-кBp65.CONCLUSION The results suggested that Angiopep-2modified scutellarin-loaded PEG-PAMAM nanocarriers possessed remarkable neuroprotective effects on ischemic stroke through modulation of inflammatory cascades and HMGB1/TLRs/MyD 88-induced NF-κB activation pathways.展开更多
OBJECTIVE Neuroinflammation plays a critical role in neurodegenerative disorders,although the inflammation may not the initiating factor.Parkinson disease(PD)is characterized pathologically by the accumulation of alph...OBJECTIVE Neuroinflammation plays a critical role in neurodegenerative disorders,although the inflammation may not the initiating factor.Parkinson disease(PD)is characterized pathologically by the accumulation of alpha synuclein(α-syn)and the loss of the dopamine(DA)neurons in the substantia nigra(SN),which has been reported to be induced by the stereotaxic injection of lipopolysaccharide(LPS)to the SN region in rodents.This study is to investigate the therapeutic benefit of the inhibition of miR-873 in PD.METHODS Rats received the right-unilaterally injection with concentrated LV-sponge or LV-EGFP 3 d before LPS treatment,7 or 14 d after LPS treatment.The animals were tested for rotational behavior with the dopaminergic agonist apomorphine dissolved in sterile saline at 21 d after LPS injection.The regulation of miR-873 on the genes related with cholesterol transport and inflammation was assayed in SH-SY5Y cells and U251 cells.RESULTS TLR4-My D88 signaling pathway was involved the regulation of miR-873 by LPS.The luciferase assay showed that HMGCR,ABCA1 and A20 were down-stream genes of miR-873.The transfection of miR-873 decreased the cholesterol levels in cell membrane,but increased in lysosome in SH-SY5Y cells.Compared with the control SH-SY5Y cells,cholesterol levels were higher in lysosome withα-synuclein overexpression or LPS treatment.The transfection of miR-873 increased theα-syn levels in lysosome in cel s withα-synuclein overexpression.The loss of dopaminergic neuorns induced by LPS was significantly respectively decreased by 22.8%,35.6%and 57% after the inhibition of miR-873 at 3 d before LPS treatment,7 or14 d after LPS treatment.Compared with LPS-treated group,the number of the rotation of rats was decreased by 60.4%,33.5%and 13.2%after the inhibition of miR-873 at 3 d before LPS treatment,7or 14 d after LPS treatment.The inhibition of miR-873 significantly decreased accumulation ofα-syn.The m RNA levels of HMGCR,ABCA1 and A20 in SN were decreased by LPS treatment,which was attenuated by the injection of LV-sponge.CONCLUSION The selective regulation of miR-873 can protect the dopaminergic neurons from the LPS-induced damage.The inhibition of miR-873 can attenuate the relocation of cholesterol in lysosome and the accumulation ofα-syn in neurons induced by LPS via the regulation of HMGCR,ABCA1 and A20.展开更多
基金The project supported by National Natural Science Foundation of China(NSFC 21476054)the Natural Science Foundation of Heilongjiang Province(B201407)
文摘OBJECTIVE The greatest challenge in chemotherapy of ischemic stroke is the construction a suitable delivery system to overcome the poor physicochemical properties of drug and its low permeability across the blood brain barrier(BBB).METHODS In the present study,dendrimer,polyamidoamine(PAMAM),was synthesized as the nano-drug carriers.Angiopep-2,which has been proved excellent ability to cross the BBB,was exploited as the targeting ligand to conjugate PAMAM via bifunctional polyethylene glycol(PEG).Then scutellarin(STA)was encapsulated into the functionalized nanoparticles(NPs)to formulate Angiopep-2 modified STA-loaded PEG-PAMAM NPs.Ischemic stroke model was established to evaluate the treatment efficacy and protective mechanism of Angiopep-2-STA-PEG-PAMAM NPs.RESULTS The pharmacokinetics and biodistribu-tion demonstrated that Angiopep-2-STA-PEG-PAMAM NPs exhibited significantly higher plasma concentration from 1 h to 10 h after intravenous administration and improve accumulation in brain(4.7-fold)compared with STA solution.Moreover,prolonged elimination half-life(4.8-fold)and lower clearance(3.4-fold)were observed.The brain uptake study of 6-coumarin confirmed that Angiopep-2-PEG-PAMAM NPs possessed better brain targeting efficacy(3.2-fold)than PEG-PAMAM NPs.Angiopep-2-STA-PEG-PAMAM NPs obviously ameliorated infarct volume,neurological deficit,histopathological severity and neuronal apoptosis.In addition,Angiopep-2-STA-PEG-PAMAM NPs markedly inhibited the calcium content and the levels of IL-12p40,IL-13,IL-17 and IL-23.Furthermore,Angiopep-2-STA-PEG-PAMAM NPs significantly decreased the m RNA and protein expressions of HMGB1,TLR2,TLR4,TLR5,My D88,TRIF,TRAM,IRAK-4,TRAF6,IкBα,IKKβand NF-кBp65.CONCLUSION The results suggested that Angiopep-2modified scutellarin-loaded PEG-PAMAM nanocarriers possessed remarkable neuroprotective effects on ischemic stroke through modulation of inflammatory cascades and HMGB1/TLRs/MyD 88-induced NF-κB activation pathways.
基金supported by National Natural Science Foundation of China(1673503)
文摘OBJECTIVE Neuroinflammation plays a critical role in neurodegenerative disorders,although the inflammation may not the initiating factor.Parkinson disease(PD)is characterized pathologically by the accumulation of alpha synuclein(α-syn)and the loss of the dopamine(DA)neurons in the substantia nigra(SN),which has been reported to be induced by the stereotaxic injection of lipopolysaccharide(LPS)to the SN region in rodents.This study is to investigate the therapeutic benefit of the inhibition of miR-873 in PD.METHODS Rats received the right-unilaterally injection with concentrated LV-sponge or LV-EGFP 3 d before LPS treatment,7 or 14 d after LPS treatment.The animals were tested for rotational behavior with the dopaminergic agonist apomorphine dissolved in sterile saline at 21 d after LPS injection.The regulation of miR-873 on the genes related with cholesterol transport and inflammation was assayed in SH-SY5Y cells and U251 cells.RESULTS TLR4-My D88 signaling pathway was involved the regulation of miR-873 by LPS.The luciferase assay showed that HMGCR,ABCA1 and A20 were down-stream genes of miR-873.The transfection of miR-873 decreased the cholesterol levels in cell membrane,but increased in lysosome in SH-SY5Y cells.Compared with the control SH-SY5Y cells,cholesterol levels were higher in lysosome withα-synuclein overexpression or LPS treatment.The transfection of miR-873 increased theα-syn levels in lysosome in cel s withα-synuclein overexpression.The loss of dopaminergic neuorns induced by LPS was significantly respectively decreased by 22.8%,35.6%and 57% after the inhibition of miR-873 at 3 d before LPS treatment,7 or14 d after LPS treatment.Compared with LPS-treated group,the number of the rotation of rats was decreased by 60.4%,33.5%and 13.2%after the inhibition of miR-873 at 3 d before LPS treatment,7or 14 d after LPS treatment.The inhibition of miR-873 significantly decreased accumulation ofα-syn.The m RNA levels of HMGCR,ABCA1 and A20 in SN were decreased by LPS treatment,which was attenuated by the injection of LV-sponge.CONCLUSION The selective regulation of miR-873 can protect the dopaminergic neurons from the LPS-induced damage.The inhibition of miR-873 can attenuate the relocation of cholesterol in lysosome and the accumulation ofα-syn in neurons induced by LPS via the regulation of HMGCR,ABCA1 and A20.