The formation of amyloid fibrils from soluble proteins is a common form of self-assembly phenomenon that has fundamental connections with biological functions and human diseases.Lysozyme was converted from its soluble...The formation of amyloid fibrils from soluble proteins is a common form of self-assembly phenomenon that has fundamental connections with biological functions and human diseases.Lysozyme was converted from its soluble native state into highly organized amyloid fibrils.Ultrasonic treatment was used to break amyloid fibrils to fibrillar fragments–seeds.Atomic force microscopy and fluorescence microscopy was employed to characterize the morphology of the amyloid assemblies and neural cells–amyloid complexes.Our results demonstrate that prefibrillar intermediated and their mixture with proteins exhibit toxicity,although native proteins and fibrils appear to have no effect on number of cells.Our findings confirm that innocuous hen lysozyme can be engineered to produce both cytotoxic fibrillar fragments and non-toxic mature amyloid fibrils.Our work further strengthens the claim that amyloid conformation,and not the identity of the protein,is key to cellular toxicity and the underlying specific cell death mechanism.展开更多
The modification of amyloid fibrils cytotoxicity through exogenous nanomaterials is crucial to understand the processes controlling the role of protein aggregation in the related diseases.The influence of nanoparticle...The modification of amyloid fibrils cytotoxicity through exogenous nanomaterials is crucial to understand the processes controlling the role of protein aggregation in the related diseases.The influence of nanoparticles on amyloid stability yields great interest due to the small size and high surface area-to-volume ratio of nanoparticles.Various physico-chemical parameters play a role in the interaction of proteins and nanoparticles in solution,thus influencing the disaggregation of preformed fibrils.We have examined the influence of two kinds of metallic nanoparticles on lysozyme amyloid fibrils using a multi-technique approach and focalized their impact on cytotoxicity on human neuroblastoma cells(SH-SY5Y).In particular,fluorescence,infrared and circular dichroism spectroscopies,optical and atomic force microscopy experiments have been carried out;the results are analyzed to rationalize the effects of these complexes on neural cell viability.It is remarkable,that the fibrils in the presence of AuNPs,unlike fibrils alone or with AgNPs,do not generate a significant cytotoxic effect even at high concentration and an amyloid degradation effect is visible.展开更多
基金supported by Slovak grand agency VEGA 2/0145/17,MVTS COST 083/14 action BM1405,SAS-MOST JRP 2015/5 and CNR-SAS bilateral projects CUP B52F15000340005 and CUP B52I12000320005,Italian flagship NANOMAX,N-CHEM。
文摘The formation of amyloid fibrils from soluble proteins is a common form of self-assembly phenomenon that has fundamental connections with biological functions and human diseases.Lysozyme was converted from its soluble native state into highly organized amyloid fibrils.Ultrasonic treatment was used to break amyloid fibrils to fibrillar fragments–seeds.Atomic force microscopy and fluorescence microscopy was employed to characterize the morphology of the amyloid assemblies and neural cells–amyloid complexes.Our results demonstrate that prefibrillar intermediated and their mixture with proteins exhibit toxicity,although native proteins and fibrils appear to have no effect on number of cells.Our findings confirm that innocuous hen lysozyme can be engineered to produce both cytotoxic fibrillar fragments and non-toxic mature amyloid fibrils.Our work further strengthens the claim that amyloid conformation,and not the identity of the protein,is key to cellular toxicity and the underlying specific cell death mechanism.
基金This work was partially supported by Slovak grand agency VEGA 2/0145/17,APW-18-0284,Italian flagship NANOMAX,N-CHEM,Ministery o f Education,University and Research(PRIN grant 20173L7W8K).Microscopy was carried out at the SPM@ISMN facility.
文摘The modification of amyloid fibrils cytotoxicity through exogenous nanomaterials is crucial to understand the processes controlling the role of protein aggregation in the related diseases.The influence of nanoparticles on amyloid stability yields great interest due to the small size and high surface area-to-volume ratio of nanoparticles.Various physico-chemical parameters play a role in the interaction of proteins and nanoparticles in solution,thus influencing the disaggregation of preformed fibrils.We have examined the influence of two kinds of metallic nanoparticles on lysozyme amyloid fibrils using a multi-technique approach and focalized their impact on cytotoxicity on human neuroblastoma cells(SH-SY5Y).In particular,fluorescence,infrared and circular dichroism spectroscopies,optical and atomic force microscopy experiments have been carried out;the results are analyzed to rationalize the effects of these complexes on neural cell viability.It is remarkable,that the fibrils in the presence of AuNPs,unlike fibrils alone or with AgNPs,do not generate a significant cytotoxic effect even at high concentration and an amyloid degradation effect is visible.
