Evidence map›Paper›PMID 32180552›Full record

ArticleMolecular metabolism2020

Irisin: Still chasing shadows.

Elke Albrecht, Lisa Schering, Friedrich Buck, Konrad Vlach, Hans-Christof Schober, Christian A Drevon, Steffen Maak

Open access · goldAbstract read
In one paragraph

Article in Molecular metabolism, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 54 papers, 3 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
54citing papers in PubMed, 3 pooled it
6.1field-weighted citation impact, top 3% 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

54 citing papers in PubMed, 3 syntheses or guidelines pooled it, 73 citations in OpenAlex.

  1. Protective role of irisin on bone in osteoporosis: a systematic review of rodent studies.Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA · 2025
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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

7 authors at 4 institutions in 2 countries.

Elke AlbrechtInstitute of Muscle Biology and Growth, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany.
Lisa ScheringInstitute of Muscle Biology and Growth, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany.
Friedrich BuckInstitute of Clinical Chemistry, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Konrad VlachDepartment of Internal Medicine I, Municipal Hospital Suedstadt Rostock, Rostock, Germany.
Hans-Christof SchoberDepartment of Internal Medicine I, Municipal Hospital Suedstadt Rostock, Rostock, Germany.
Christian A DrevonDepartment of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
Steffen MaakInstitute of Muscle Biology and Growth, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany. Electronic address: maak@fbn-dummerstorf.de.
Research Institute for Farm Animal Biology (FBN) · DEKlinikum Südstadt Rostock · DEUniversität Hamburg · DEUniversity of Oslo · NO

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveConsiderable uncertainty remains regarding the veracity of measuring myokine irisin more than seven years after its original description. Unresolved issues include the nature of transcription of the irisin precursor fibronectin type III domain containing 5 (FNDC5) gene across species, the reliability of irisin levels measured with commercial enzyme-linked immunosorbent assays (ELISAs), and the overall validity of the recently published reference values for human serum measured with quantitative mass spectrometry. We utilized multiple species and measures to evaluate the robustness of commonly used reagents and methods for reporting irisin.

methodsAmplification of cDNA was used to assess the FNDC5 transcript patterns in humans and mice. The specificity and sensitivity of different irisin antibodies were examined via western blotting. Quantification of circulating native irisin was conducted with mass spectrometry using an absolute quantification peptide for irisin.

resultsWe show that there is a greater transcript diversity of human FNDC5 than currently annotated, but no indication of the expression of transcripts leading to a truncated form of irisin. Available irisin antibodies still bind to patterns of unspecific serum proteins, which compromise reliable measurements of irisin with ELISAs. Absolute quantification of irisin with labeled peptides by mass spectrometry is an advanced method but requires a multi-step sample preparation introducing uncontrollable variations in the measurement.

conclusionOur data represent an explicit warning against measuring circulating irisin using available methods. Measuring irisin is akin to chasing shadows.

Indexed as

AnimalsEquidaeFibronectinsGoatsHumansMass SpectrometryMiceMusclesPapioRabbitsRatsFibronectinsFNDC5 protein, humanFNDC5 protein, mouseAdipose tissueFNDC5Mass spectrometryPlasmaSkeletal muscleTranscript

Identifiers

PMID32180552
PMCPMC7033458
OpenAlexW3004340994

What Socratic 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 Socratic graph.