Abstract
The transport and accumulation of orally administered functional food-derived peptides in the brain was not fully explored. Thus, in the present study, we aimed to provide critical evidence ...regarding brain accumulation of a memory-improving soy dipeptide, Tyr-Pro, following oral administration. Stable isotope-labeled Tyr-Pro (Tyr-
13
C
5
,
15
NPro) was orally administered to male ICR mice at 10 or 100 mg/kg. Surprisingly, the intact labeled Tyr-Pro exhibited maximal plasma and brain levels 15 min after administration (plasma: area under the curve
AUC
0–120 min
, 1331 ± 267 pmol·min/mL-plasma; brain:
AUC
0–120 min
of 0.34 ± 0.11 pmol·min/mg-dry brain, at 10 mg/kg). In addition, we detected labeled Tyr-Pro in the brain parenchyma, indicating a validated blood–brain-barrier (BBB) transportability. Moreover, we confirmed the preferable accumulation of Tyr-Pro in the hypothalamus, hippocampus, and cortex with > 0.02 pmol/mg-tissue. In conclusion, we provided the first evidence that orally administered Tyr-Pro at 10 mg/kg directly entered the blood circulation with an absorption ratio of 0.15%, of which 2.5% of Tyr-Pro was transported from the plasma to the mouse brain parenchyma.
A trip of peptides to the brain Matsui, Toshiro; Yoshino, Atsuko; Tanaka, Mitsuru
Food production, processing and nutrition,
12/2020, Volume:
2, Issue:
1
Journal Article
Peer reviewed
Open access
Abstract
Dietary di/tripeptides elicit preventive effects against lifestyle-related diseases such as hypertension, and hypercholesterolemia, etc. Although there have been evidential reports that the ...intake of protein hydrolysate improved impaired memory in human, limited studies on bioavailability, in particular, beyond the blood-brain barrier (BBB) of candidates in hydrolysate may prevent their extensive physiological studies. Thus, this review discusses the updated studies on BBB transport of peptides showing improved cognitive decline. Furthermore, their accumulation in the brain cerebral parenchyma is also introduced.
Graphical abstract
In this study, experiments on amyloid β peptide25-35-induced mice were performed to provide in vivo evidence on the potential of the blood–brain barrier transportable soy dipeptide, Tyr-Pro, in ...combating memory impairment. We demonstrated for the first time that oral administration of Tyr-Pro (100 mg/kg, twice a day) in mice for 16 days significantly improved impaired memory by spontaneous alternation and shortened step-through latency in amyloid β-induced mice.
To examine the performance of liquid-based cytology (LBC) in breast cytology to confirm the diagnosis of carcinoma.
Using cell clusters directly scratched from surgically removed tumor masses, we ...examined the immunocytochemistry, molecular biology and cytomorphology of the specimens.
LBC was very useful for gene analysis and evaluating the immunocytochemistry. The cytologic features of LBC were slightly different from those ofa conventional aspiration cytology smear.
LBC is a promising method for improving the standardization ofpreparations in breast cytology, although care should be taken to account for its characteristic cytologic features. The quantitative analysis of HER-2 mRNA correlated with the results of immunohistochemistry.
In this study, experiments on amyloid β peptide
-induced mice were performed to provide in vivo evidence on the potential of the blood-brain barrier transportable soy dipeptide, Tyr-Pro, in combating ...memory impairment. We demonstrated for the first time that oral administration of Tyr-Pro (100 mg/kg, twice a day) in mice for 16 days significantly improved impaired memory by spontaneous alternation and shortened step-through latency in amyloid β-induced mice.
The objective of this report is to examine the background behind, and grasp the present situation of and issues for, reduced class sizes for home economics classes in Tokyo high schools. This was ...accomplished through analysis of Tokyo High School Home Economics Education Research Committee (THR) activity reports (1966~2013), and by interviewing teaching staff. In 2015, in order to gauge the present circumstances and issues concerning reduced class sizes home economics teachers were mailed questionnaires and 73 responses were attained. The following was discovered. Reduced class sizes for home economics classes in Tokyo high schools has been progressively implemented and developed due to continued petitions and requests from the THR based on generational issues in home economics classes and through proven success of the initiative. Furthermore, a 2015 survey on reduced class sizes showed that its implementation prevents home economics credits being lowered and helps limit reduction of full-time teachers of home economics. 87.7% of home economics teachers that experienced class size reduction reported that it was ‘good’ because it encourages active learning. However, there is significant variation in the understanding of class size reduction amongst teachers. Therefore, teacher training in this initiative remains an issue.
Background: Streptococcal protein G and staphylococcal protein A are bacterial antibody-binding proteins, widely used as immunological tools, whose antibody-binding domains are structurally quite ...different. The binding of protein G to Fc fragments is competitive with respect to protein A, suggesting that the binding sites for protein A and protein G on Fc overlap, notwithstanding the fact that they lack sequence or structural similarity. .
Results To resolve this issue, the residues involved in the interaction between an IgG-binding domain of protein G (domain II) and the Fc fragment of mouse IgG2a have been identified by use of
13 C and
15 N NMR. Binding of protein G domain II selectively perturbed resonances from residues between the C
H 2 and C
H 3 domains of Fc, whereas in domain II the residues affected are primarily those on the
α–helix and the third strand of the
β–sheet. This information was used, together with the structures of the two uncomplexed proteins, to construct a model of the complex, using Monte Carlo minimization techniques. In this model, the
α–helix of protein G lies in the same position as helix 1 of protein A in the crystal structure of the protein A:Fc complex, but its orientation differs from the latter by 180°. .
Conclusion The interactions of the bacterial antibody-binding proteins with their ‘target’ immunoglobulins involve a very versatile set of protein–protein interactions. First, the IgG-binding domains of protein A and protein G have quite different three-dimensional structures, but bind to sites on the Fc fragment that overlap extensively. Secondly, protein G employs two quite different regions of its surface to bind to the Fab and Fc regions of IgG.
The thermal stability of the murine MHC class II molecule, I-A(b), in complex with invariant chain-derived peptide (CLIP) and an antigenic peptide derived from the alpha subunit of the I-E molecule ...(Ealpha) at mildly acidic and neutral pH were analyzed using circular dichroism (CD). The stability of I-A(b)-CLIP was increased by a single amino acid substitution in the P1 anchor residue, from Met of CLIP to Phe of Ealpha, similar, in this respect, to I-A(b)-Ealpha. This indicates that hydrophobic interaction in the P1 pocket is critical and plays a primary role in the stability of the complex. The structural models of I-A(b)-peptides based on the crystal structure of I-A(d) might explain the increased stability and the preference for hydrophobic residues in this site. Taken together with what is known of the resident stability at a mildly acidic pH, the difference in stability would closely correlate with the ability of MHC class II to exchange peptides from CLIP to antigenic peptides in the endosome.
Golgins are Golgi-localized proteins present in all molecularly characterized eukaryotes that function in Golgi transport and maintenance of Golgi structure. Some peripheral membrane Golgins, ...including the yeast Imh1 protein, contain the recently described GRIP domain that can independently mediate Golgi localization by an unknown mechanism 1–3. To identify candidate Golgi receptors for GRIP domain proteins, a collection of Saccharomyces cerevisiae deletion mutants was visually screened by using yeast, mouse, and human GFP-GRIP domain fusion proteins for defects in Golgi localization. GFP-GRIP reporters were localized to the cytosol in cells lacking either of two ARF-like (ARL) GTPases, Arl1p and Arl3p. In vitro binding experiments demonstrated that activated Arl1p-GTP binds specifically and directly to the Imh1p GRIP domain. Arl1p colocalized with Imh1p-GRIP at the Golgi, and Golgi localization of Arl1p was regulated by the GTPase cycle of Arl3p. These results suggest a cascade in which the GTPase cycle of Arl3p regulates Golgi localization of Arl1p, which in turn binds to the GRIP domain of Imh1p and recruits it to the Golgi. The similar requirements for localization of GRIP domains from yeast, mouse, and human when expressed in yeast, and the presence of Arl1p and Arl3p homologs in these species, suggest that this is an evolutionarily conserved mechanism.
In this study, experiments on amyloid β peptide
-induced mice were performed to provide in vivo evidence on the potential of the blood-brain barrier transportable soy dipeptide, Tyr-Pro, in combating ...memory impairment. We demonstrated for the first time that oral administration of Tyr-Pro (100 mg/kg, twice a day) in mice for 16 days significantly improved impaired memory by spontaneous alternation and shortened step-through latency in amyloid β-induced mice.
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