Evidence map›Paper›PMID 33557896›Full record

ArticleMolecular neurodegeneration2021

Relationships of gut microbiota, short-chain fatty acids, inflammation, and the gut barrier in Parkinson's disease.

Velma T E Aho, Madelyn C Houser, Pedro A B Pereira, Jianjun Chang, Knut Rudi, Lars Paulin, Vicki Hertzberg, Petri Auvinen, Malú G Tansey, Filip Scheperjans

3 registry-linked trialsOpen access · goldAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in Molecular neurodegeneration, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to 3 registered trials, which are not on this map. Cited by 265 papers, 6 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
265citing papers in PubMed, 6 pooled it
30.9field-weighted citation impact, top 1% 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.

NCT05469997 nacompletednot on this mapstarted 2023, after this paper: background citation

Ketogenic Diet Interventions in Parkinson's Disease: Safeguarding the Gut Microbiome

TypeinterventionalSponsorUniversity of British ColumbiaRan2023 to 2024Enrolled52ConditionsParkinson DiseaseArmsMediterranean-Ketogenic Diet, Mediterranean diet supplemented with medium-chain triglyceride oil
NCT06463769 nanot yet recruitingnot on this mapstarted 2026, after this paper: background citation

"Impact of Diet on the Microbiome-Immune-Brain Axis in Parkinson's Disease" as Part of the Collaborative Research Center 1697 "Targeting the Microbiome-Immune-Brain Interaction in Neurodegeneration"

TypeinterventionalSponsorUniversity of KielRan2026 to 2028Enrolled75ConditionsParkinson DiseaseArms8 week predominantly plant-based New Nordic LPF-diet program, maintenance of the predominantly plant-based New Nordic LPF-diet
NCT07597421 nanot yet recruitingnot on this mapstarted 2026, after this paper: background citation

Fecal Microbiota Transplantation for the Treatment of Patients With Parkinson's Disease.

TypeinterventionalSponsorChang Gung Memorial HospitalRan2026 to 2029Enrolled58ConditionsParkinson's DiseaseArmsFecal microbiota transplantation, Not received Fecal microbiota transplantation
3 · Its place in the literature

Who cites it

265 citing papers in PubMed, 6 syntheses or guidelines pooled it, 395 citations in OpenAlex.

  1. Beyond bacteria: a multi-omics view of the gut-brain axis in Parkinson's disease.Frontiers in cellular and infection microbiology · 2026
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  11. Cellular and systemic modifiers of alpha-synuclein proteostasis.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2026
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205 more citing papers are in PubMed but not listed here.

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

10 authors at 3 institutions in 3 countries.

Velma T E Aho *DNA Sequencing and Genomics Laboratory, Institute of Biotechnology, University of Helsinki, Viikinkaari 5D, 00790, Helsinki, Finland.ORCID 0000-0003-2916-7018
Madelyn C Houser *Nell Hodgson Woodruff School of Nursing, Emory University, 1520 Clifton Rd, Atlanta, GA, 30322, USA.ORCID 0000-0002-4049-9876
Pedro A B PereiraDNA Sequencing and Genomics Laboratory, Institute of Biotechnology, University of Helsinki, Viikinkaari 5D, 00790, Helsinki, Finland.ORCID 0000-0002-2967-2252
Jianjun ChangDepartment of Physiology, Emory University School of Medicine, 615 Michael St, Atlanta, GA, 30322, USA.
Knut RudiFaculty of Chemistry, Biotechnology and Food Science (KBM), Norwegian University of Life Sciences, 1433, Oslo, Ås, Norway.
Lars PaulinDNA Sequencing and Genomics Laboratory, Institute of Biotechnology, University of Helsinki, Viikinkaari 5D, 00790, Helsinki, Finland.ORCID 0000-0003-0923-1254
Vicki HertzbergNell Hodgson Woodruff School of Nursing, Emory University, 1520 Clifton Rd, Atlanta, GA, 30322, USA.ORCID 0000-0002-8834-4363
Petri AuvinenDNA Sequencing and Genomics Laboratory, Institute of Biotechnology, University of Helsinki, Viikinkaari 5D, 00790, Helsinki, Finland.ORCID 0000-0002-3947-4778
Malú G TanseyDepartment of Physiology, Emory University School of Medicine, 615 Michael St, Atlanta, GA, 30322, USA. mgtansey@UFL.edu.ORCID 0000-0002-1719-4708
Filip ScheperjansDepartment of Neurology, Helsinki University Hospital, and Department of Neurological Sciences (Neurology), University of Helsinki, ward K4A, Haartmaninkatu 4, FI-00290, Helsinki, Finland. filip.scheperjans@hus.fi.ORCID 0000-0001-9502-7131
University of Helsinki · FIEmory University · USNorwegian University of Life Sciences · NO

Funding

Role of HLA/MHCII in Parkinson's Disease PathogenesisR01NS092122 · NINDS · EMORY UNIVERSITY · PI BOSS, JEREMY M., TANSEY, MARIA DE LOURDES GAMEZ · 2015 to 2019
$1.8M
NINDS NIH HHS R01 NS092122
6 · The paper itself

Abstract

backgroundPrevious studies have reported that gut microbiota, permeability, short-chain fatty acids (SCFAs), and inflammation are altered in Parkinson's disease (PD), but how these factors are linked and how they contribute to disease processes and symptoms remains uncertain. This study sought to compare and identify associations among these factors in PD patients and controls to elucidate their interrelations and links to clinical manifestations of PD.

methodsStool and plasma samples and clinical data were collected from 55 PD patients and 56 controls. Levels of stool SCFAs and stool and plasma inflammatory and permeability markers were compared between patients and controls and related to one another and to the gut microbiota.

resultsCalprotectin was increased and SCFAs decreased in stool in PD in a sex-dependent manner. Inflammatory markers in plasma and stool were neither intercorrelated nor strongly associated with SCFA levels. Age at PD onset was positively correlated with SCFAs and negatively correlated with CXCL8 and IL-1β in stool. Fecal zonulin correlated positively with fecal NGAL and negatively with PD motor and non-motor symptoms. Microbiota diversity and composition were linked to levels of SCFAs, inflammatory factors, and zonulin in stool. Certain relationships differed between patients and controls and by sex.

conclusionsIntestinal inflammatory responses and reductions in fecal SCFAs occur in PD, are related to the microbiota and to disease onset, and are not reflected in plasma inflammatory profiles. Some of these relationships are distinct in PD and are sex-dependent. This study revealed potential alterations in microbiota-host interactions and links between earlier PD onset and intestinal inflammatory responses and reduced SCFA levels, highlighting candidate molecules and pathways which may contribute to PD pathogenesis and clinical presentation and which warrant further investigation.

Indexed as

AgedBiomarkersFatty Acids, VolatileFemaleGastrointestinal MicrobiomeHaptoglobinsHumansInflammationMaleMiddle AgedParkinson DiseaseProtein PrecursorsBiomarkersFatty Acids, VolatileHaptoglobinsProtein PrecursorszonulinInflammationIntestineMicrobiotaParkinson’s diseaseShort-chain fatty acids

Identifiers

PMID33557896
PMCPMC7869249
OpenAlexW3127379712

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

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.