Evidence mapPaperPMID 34081167Full record

ArticleEuropean journal of nutrition2021

Macroalgal protein hydrolysates from Palmaria palmata influence the 'incretin effect' in vitro via DPP-4 inhibition and upregulation of insulin, GLP-1 and GIP secretion.

C M McLaughlin, P A Harnedy-Rothwell, R A Lafferty, S Sharkey, V Parthsarathy, P J Allsopp, E M McSorley, R J FitzGerald, F P M O'Harte

Open access · hybridAbstract read
In one paragraph

Article in European journal of nutrition, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.

0numbers the graph read from it
0cells of the map it votes in
14citing papers in PubMed
1.5field-weighted citation impact, top 18% 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

14 citing papers in PubMed, 33 citations in OpenAlex.

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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

9 authors at 2 institutions in 2 countries.

C M McLaughlinSchool of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Co. Derry, BT52 1SA, Northern Ireland.
P A Harnedy-RothwellDepartment of Biological Sciences, University of Limerick, Castletroy, Limerick, Ireland.
R A LaffertySchool of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Co. Derry, BT52 1SA, Northern Ireland.
S SharkeySchool of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Co. Derry, BT52 1SA, Northern Ireland.
V ParthsarathySchool of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Co. Derry, BT52 1SA, Northern Ireland.
P J AllsoppNutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Co. Derry, BT52 1SA, Northern Ireland.
E M McSorleyNutrition Innovation Centre for Food and Health, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Co. Derry, BT52 1SA, Northern Ireland.
R J FitzGeraldDepartment of Biological Sciences, University of Limerick, Castletroy, Limerick, Ireland.
F P M O'HarteSchool of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Co. Derry, BT52 1SA, Northern Ireland. fpm.oharte@ulster.ac.uk.ORCID http://orcid.org/0000-0002-7199-4239
University of Ulster · GBUniversity of Limerick · IE

Funding

Department of Agriculture, Food and the Marine (IE) 11/F/063Department of Agriculture, Food and the Marine (IE) 11/F064Department of Agriculture, Food and the Marine (IE) 13/F536Department of Agriculture, Food and the Marine (IE) 14/F873Department of Education & Learning, Northern Ireland PhD Studentship
6 · The paper itself

Abstract

purposeThis study investigated metabolic benefits of protein hydrolysates from the macroalgae Palmaria palmata, previously shown to inhibit dipeptidylpeptidase-4 (DPP-4) activity in vitro.

methodsPreviously, Alcalase/Flavourzyme-produced P. palmata protein hydrolysate (PPPH) improved glycaemia and insulin production in streptozotocin-induced diabetic mice. Here the PPPH, was compared to alternative Alcalase, bromelain and Promod-derived hydrolysates and an unhydrolysed control. All PPPH's underwent simulated gastrointestinal digestion (SGID) to establish oral bioavailability. PPPH's and their SGID counterparts were tested in pancreatic, clonal BRIN-BD11 cells to assess their insulinotropic effect and associated intracellular mechanisms. PPPH actions on the incretin effect were assessed via measurement of DPP-4 activity, coupled with GLP-1 and GIP release from GLUTag and STC-1 cells, respectively. Acute in vivo effects of Alcalase/Flavourzyme PPPH administration on glucose tolerance and satiety were assessed in overnight-fasted mice.

resultsPPPH's (0.02-2.5 mg/ml) elicited varying insulinotropic effects (p < 0.05-0.001). SGID of the unhydrolysed protein control, bromelain and Promod PPPH's retained, or improved, bioactivity regarding insulin secretion, DPP-4 inhibition and GIP release. Insulinotropic effects were retained for all SGID-hydrolysates at higher PPPH concentrations. DPP-4 inhibitory effects were confirmed for all PPPH's and SGID counterparts (p < 0.05-0.001). PPPH's were shown to directly influence the incretin effect via upregulated GLP-1 and GIP (p < 0.01-0.001) secretion in vitro, largely retained after SGID. Alcalase/Flavourzyme PPPH produced the greatest elevation in cAMP (p < 0.001, 1.7-fold), which was fully retained post-SGID. This hydrolysate elicited elevations in intracellular calcium (p < 0.01) and membrane potential (p < 0.001). In acute in vivo settings, Alcalase/Flavourzyme PPPH improved glucose tolerance (p < 0.01-0.001) and satiety (p < 0.05-0.001).

conclusionBioavailable PPPH peptides may be useful for the management of T2DM and obesity.

Indexed as

Diabetes Mellitus, ExperimentalGlucagon-Like Peptide 1AnimalsBlood GlucoseGastric Inhibitory PolypeptideIncretinsInsulinMiceProtein HydrolysatesUp-RegulationBlood GlucoseGastric Inhibitory PolypeptideGlucagon-Like Peptide 1IncretinsInsulinProtein HydrolysatesAntidiabeticDipeptidylpeptidase-4DulseIncretin secretionPalmaria palmataProtein hydrolysateType 2 diabetes

Identifiers

PMID34081167
PMCPMC8572210
OpenAlexW3164462872

What Socratic holds

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LicenceCC BY
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Registered trials

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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 Socratic graph.