Frequent concomitant manifestation of type 2 diabetesmellitus (T2DM) and Alzheimer's disease (AD) hasbeen recently demonstrated by epidemiological studies.This might be due to functional similarities between β-ce...Frequent concomitant manifestation of type 2 diabetesmellitus (T2DM) and Alzheimer's disease (AD) hasbeen recently demonstrated by epidemiological studies.This might be due to functional similarities between β-cells and neurons, such as secretion on demand ofhighly specific molecules in a tightly controlled fashion.An additional similarity represents the age-relatedalteration of hyperphosphorylated tau in AD patients.Similarly, alterations have been identified in β-cells of T2DM patients. The islet amyloid polypeptide has beenassociated with β-cell apoptosis. As a consequence ofincreasing age, the accumulation of highly modified proteins together with decreased regenerative potentialmight lead to increasing rates of apoptosis. Moreover, reduction of β-cell replication capabilities results in reduction of β-cell mass in mammals, simultaneously withimpaired glucose tolerance. The new challenge is tolearn much more about age-related protein modifications. This can lead to new treatment strategies forreducing the incidence of T2DM and AD.展开更多
A thorough understanding of how proteins induce nanoparticle (NP) aggregation is crucial when designing in vitro and in vivo assays and interpreting experimental results. This knowledge is also crucial when developi...A thorough understanding of how proteins induce nanoparticle (NP) aggregation is crucial when designing in vitro and in vivo assays and interpreting experimental results. This knowledge is also crucial when developing nano-applications and formulation for drug delivery systems. In this study, we found that extraction of immunoglobulin G (IgG) from cow serum results in lower polystyrene NPs aggregation. Moreover, addition of isolated IgG or fibrinogen to fetal cow serum enhanced this aggregation, thus demonstrating that these factors are major drivers of NP aggregation in serum. Counter-intuitively, NP aggregation was inversely dependent on protein concentration; i.e., low protein concentrations induced large aggregates, whereas high protein concentrations induced small aggregates. Protein-induced NP aggregation and aggregate size were monitored by absorbance at 400 nm and dynamic light scattering, respectively. Here, we propose a mechanism behind the protein concentration dependent aggregation; this mechanism involves the effects of multiple protein interactions on the NP surface, surface area limitations, aggregation kinetics, and the influence of other serum proteins.展开更多
基金Supported by the Grant from the National Bank of Austria,No.13402the Fund of the Major of the City of Vienna,No.08052
文摘Frequent concomitant manifestation of type 2 diabetesmellitus (T2DM) and Alzheimer's disease (AD) hasbeen recently demonstrated by epidemiological studies.This might be due to functional similarities between β-cells and neurons, such as secretion on demand ofhighly specific molecules in a tightly controlled fashion.An additional similarity represents the age-relatedalteration of hyperphosphorylated tau in AD patients.Similarly, alterations have been identified in β-cells of T2DM patients. The islet amyloid polypeptide has beenassociated with β-cell apoptosis. As a consequence ofincreasing age, the accumulation of highly modified proteins together with decreased regenerative potentialmight lead to increasing rates of apoptosis. Moreover, reduction of β-cell replication capabilities results in reduction of β-cell mass in mammals, simultaneously withimpaired glucose tolerance. The new challenge is tolearn much more about age-related protein modifications. This can lead to new treatment strategies forreducing the incidence of T2DM and AD.
文摘A thorough understanding of how proteins induce nanoparticle (NP) aggregation is crucial when designing in vitro and in vivo assays and interpreting experimental results. This knowledge is also crucial when developing nano-applications and formulation for drug delivery systems. In this study, we found that extraction of immunoglobulin G (IgG) from cow serum results in lower polystyrene NPs aggregation. Moreover, addition of isolated IgG or fibrinogen to fetal cow serum enhanced this aggregation, thus demonstrating that these factors are major drivers of NP aggregation in serum. Counter-intuitively, NP aggregation was inversely dependent on protein concentration; i.e., low protein concentrations induced large aggregates, whereas high protein concentrations induced small aggregates. Protein-induced NP aggregation and aggregate size were monitored by absorbance at 400 nm and dynamic light scattering, respectively. Here, we propose a mechanism behind the protein concentration dependent aggregation; this mechanism involves the effects of multiple protein interactions on the NP surface, surface area limitations, aggregation kinetics, and the influence of other serum proteins.