A GLP-1/apelin dual receptor agonist shows neuroprotective effects in the MPTP mouse model of Parkinson's disease
- Design
- Animal study · Mixed outcome
- Match to healthy normal-weight adults aged 55–75
- Not human evidenceVERY_INDIRECT: mouse MPTP model of Parkinson's disease, non-human evidence.
- Could weight loss explain it?
- PossiblyPossibly: no body-weight or glucose data are reported for the mice; the evidence model's default is possibly, animal studies included.
- Study tier
- Study tier 4VERY_LOW: a preclinical animal study.
- Assessment
- Version 2 · Two reviewers differed; settled by a recorded ruling · Oct 19, 2026
Study facts come from the paper. Population match, weight-loss explanation and study tier are our judgments, made against the reference group of healthy normal-weight adults aged 55–75.
In mice given a toxin that mimics Parkinson's disease, researchers tested a new combined GLP-1/apelin peptide (ELA) against the GLP-1 drug liraglutide. Both drugs improved movement tests, reduced brain inflammation and improved synapse and mitochondrial measures; the new peptide did better than liraglutide on some measures but not others. These are animal results and do not show effects in people.
01Findings
What the study reported
- Drugs
- Exendin-4-linker-apelin (ela)
- Comparator
- liraglutide
- Primary outcome
- Motor activity, neuroinflammation, synapse and mitochondrial measures in MPTP mice
- Effect
- Both ELA and liraglutide improved motor activity and reduced glial activation and pro-inflammatory cytokines, improved striatal synapse numbers and normalised mitochondrial measures; ELA was superior to liraglutide in some but not all parameters; no numbers in the abstract
- 95% confidence interval
- not reported in abstract
- Follow-up
- Not stated
- Adverse events
- not reported in abstract
- Limitations
- Mouse toxin model of Parkinson's disease; results in animals do not establish effects in people, and the abstract gives no group sizes or effect sizes.
Who was studied
- Obesity status
- not reported in abstract
- Diabetes status
- not reported in abstract
- Cvd status
- not reported in abstract
- Ckd status
- not reported in abstract
- Baseline condition
- MPTP mouse model of Parkinson's disease
Study quality details
- Study design
- Preclinical (animal)
- Sample size
- not extracted
- Randomization
- not reported in abstract
- Blinding
- not stated
- Comparator
- liraglutide
- Follow up duration
- not stated
- Outcome type
- mixed
- Replication
- not assessed
- Consistency with other evidence
- not assessed
- Population applicability
- VERY_INDIRECT
- Statistical precision
- no CI, p values or group sizes reported
- Risk of bias
- not assessed
- Funding conflicts
- unclear
- Peer review status
- yes
02Funding
Funding and conflicts
- Funding
- not reported in abstract
- Industry funded
- Unclear
- Manufacturer
- not stated in source
- Sponsor role
- not reported in abstract
- Author conflicts
- Authors declare no conflicts of interest.
- Independent replication
- unknown
Funding is shown on every study and never used to score it.
04Source
The source, as retrieved
Abstract
Parkinson's disease (PD) is a chronic disorder with no disease-modifying treatment available. The glucagon-like peptide-1 (GLP-1) class of drugs is on the market to treat diabetes and obesity. GLP-1 drugs have also shown neuroprotective effects in animal models and clinical trials in PD patients. Apelin (APJ) is an adipokine peptide hormone with neuroprotective actions in preclinical studies. Here, we test the effects of a rationally designed bifunctional peptide, namely ELA (exendin-4-linker-apelin), in the MPTP mouse model of PD. The single GLP-1 receptor agonist liraglutide was used as a comparator. Motor activity was improved by both drugs (open field, pole test, Rotarod), and the inflammation response was reduced (activation of microglia and astrocytes, pro-inflammatory cytokine levels). In addition, synapse numbers were improved in the striatum (Golgi strain, TEM), expression of synapse-associated proteins was enhanced, alongside reduced expression of genes that increase mitochondrial fission. Mitochondrial fusion gene expressions (Opa1, Mfn2, Drp1) and mitochondrial morphology were also normalized (TEM). ELA was superior to liraglutide in some, but not all, parameters measured. The results suggest that the rational design of bifunctional peptides targeting both GLP-1 and APJ pathways-with optimized pharmacokinetics and enhanced blood-brain barrier (BBB) permeability-merits further investigation as a strategy for developing more effective treatments for PD.