Evidence map›Paper›PMID 34115818›Full record

ArticlePloS one2021

An imaging approach for determining the mechanism of enhancement of intestinal absorption of an L-theanine supplement.

Yuki Sato, Kazuki Yamaguchi, Mikako Ogawa, Yoh Takekuma, Mitsuru Sugawara

Open access · goldAbstract read
In one paragraph

Article in PloS one, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact, top 93% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed, 0 citations in OpenAlex.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors at 2 institutions in 1 country.

Yuki SatoFaculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Hokkaido, Japan.
Kazuki YamaguchiFaculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Hokkaido, Japan.
Mikako OgawaFaculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Hokkaido, Japan.
Yoh TakekumaDepartment of Pharmacy, Hokkaido University Hospital, Sapporo, Hokkaido, Japan.
Mitsuru SugawaraFaculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Hokkaido, Japan.ORCID 0000-0001-5350-2950
Hokkaido University · JPHokkaido University Hospital · JP

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

BACKGROUND &

objectiveTheanine (L-glutamylethylamide) contained in green tea is a functional food component that has been attracting attention due to its relaxation effect. It was shown that the ingredients added to the theanine formulations increased the absorption of theanine. If this mechanism can be elucidated, it would be possible to contribute to development of evidence-based formulations. In this study, we investigated the effect of ingredients in the formulations on the absorption of theanine in detail. MAIN

methodsAfter oral administration of a mixture of theanine and additional components to Wistar rats the plasma concentration was determined by an HPLC and the pharmacokinetic parameters were calculated. In addition, a new system for evaluating intestinal blood flow was developed since the involvement of intestinal blood flow was considered as a factor that increased absorption of theanine. KEY

findingsPlasma concentration of theanine increased significantly in the combined use group with eight ingredients containing piperine as compared with theanine only group. Piperine would increase theanine absorption by increased blood flow, not an inhibition of metabolism. We succeeded to develop a visual and quantitative system to evaluate the effect of these ingredients directly including piperine on the intestinal blood flow using indocyanine green while maintaining physiological conditions. SIGNIFICANCE: Increased intestinal blood flow by these ingredients including piperine enhanced the absorption of theanine. Other mechanisms may also be considered as the mechanism by which theanine absorption is increased in addition to increased blood flow.

Indexed as

Dietary SupplementsIntestinal AbsorptionAnimalsCaco-2 CellsChromatography, High Pressure LiquidGlutamatesHumansMaleRatsRats, WistarRegional Blood FlowGlutamatestheanine

Identifiers

PMID34115818
PMCPMC8195392
OpenAlexW3169246885

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.