GLP-1 Peptide Agonist Dulaglutide Outperforms SGLT2 Inhibitors for Brain Protection After Stroke in Rats | Research

The takeaway

Dulaglutide (a GLP-1 receptor agonist) was more neuroprotective than SGLT2 inhibitors in experimental stroke, reducing both brain damage volume and neurological deficits in non-diabetic rats and protecting both neurons and glial cells in diabetic rats.

GLP-1RA > SGLT2i
Dulaglutide improved neurological status better than both SGLT2 inhibitors in non-diabetic rats after experimental stroke

What the researchers found

In non-diabetic rats (n=10 per group):

- All drugs (empagliflozin, canagliflozin, dulaglutide) reduced brain infarct size more effectively than metformin

- Dulaglutide improved neurological status better than both metformin and SGLT2 inhibitors

- All drugs reduced neurofilament light chains (NLC) and neuronal damage markers; none reduced glial marker S100BB

In diabetic rats:

- All drugs had infarct-limiting effects and reduced neurological deficits

- Untreated diabetic rats had the worst neurological outcomes

- Dulaglutide and empagliflozin (but not canagliflozin) also decreased the glial damage marker S100BB

- None affected neuron-specific enolase

Conclusion: GLP-1RA may be more neuroprotective than SGLT2i overall, with benefits on both neuronal and glial damage.

Why it matters

Stroke is a leading cause of death and disability, and diabetic patients face double the stroke risk. Finding that a GLP-1 peptide agonist provides superior brain protection compared to other diabetes drugs opens the possibility that drug choice for diabetic patients could be guided not just by glucose control but also by stroke risk reduction. The mechanistic data on neuronal versus glial protection adds depth to understanding how these drugs work in the brain.

How the study worked

Non-diabetic Wistar rats (5 groups, n=10 each) received empagliflozin, canagliflozin, dulaglutide, metformin, or saline for 7 days before induced stroke. At 48 hours post-stroke, neurological deficit, brain damage volume, and biomarkers (NLC, S100BB, neuron-specific enolase) were assessed. A parallel experiment used diabetic rats (high-fat diet + nicotinamide/streptozotocin model) with 8 weeks of drug treatment before stroke induction.

What this study cannot tell us

This is a rat study using induced stroke models that may not fully replicate human stroke pathophysiology. The sample size (n=10 per group) is standard for animal studies but limits statistical power. The drugs were given before stroke (pretreatment), which does not reflect clinical scenarios where treatment typically begins after stroke onset. Only one GLP-1RA (dulaglutide) was tested — results may differ for semaglutide or liraglutide. The 48-hour assessment window may not capture long-term outcomes.

How to read the evidence

This is a controlled preclinical animal study with appropriate comparator groups. While well-designed for an animal study, translating brain protection findings from rats to humans requires confirmation in clinical trials.

When this study was published

Published in 2024, this is recent preclinical research contributing to the active investigation of GLP-1 receptor agonists' neuroprotective potential.

The bigger picture

GLP-1 receptor agonists are increasingly recognized for organ-protective effects beyond glucose control — cardiovascular, renal, and now potentially neuroprotective. This study contributes to the growing evidence that GLP-1 receptors in the brain may mediate meaningful protection during ischemic events. If confirmed in clinical studies, this could influence prescribing decisions for diabetic patients at high stroke risk and potentially lead to investigation of GLP-1 agonists as neuroprotective agents in non-diabetic stroke patients.

Questions still open

Would GLP-1 receptor agonists provide neuroprotection when administered after stroke onset, as would be required clinically?
Do the neuroprotective effects of dulaglutide translate to reduced stroke severity in human clinical trials?
Why does empagliflozin protect glial cells in diabetes while canagliflozin does not — is SGLT2 selectivity the key factor?

Common questions

Why might a diabetes drug protect the brain during a stroke?

GLP-1 receptors are found not only in the pancreas but also in the brain. When activated, they appear to reduce inflammation, protect neurons from damage, and improve blood flow — all of which are critical during a stroke. Dulaglutide, by activating these brain GLP-1 receptors, may trigger protective pathways that limit the extent of brain tissue death when blood supply is interrupted.

Why was dulaglutide better at brain protection than the SGLT2 inhibitors?

SGLT2 inhibitors work primarily in the kidney to lower blood sugar by blocking glucose reabsorption. While they have some brain-protective effects (possibly through reducing inflammation or improving blood vessel function), they don't directly activate receptors in the brain. Dulaglutide, as a GLP-1 agonist, directly activates GLP-1 receptors on brain cells, which may explain its stronger neuroprotective effect — especially its unique ability to improve neurological function, not just reduce damage size.

Read the original research

SGLT-2 Inhibitors' and GLP-1 Receptor Agonists' Influence on Neuronal and Glial Damage in Experimental Stroke.

Biomedicines, 12(12)

View on PubMed ↗Publisher’s paper ↗

Citation

Murasheva, Anna; Fuks, Oksana; Timkina, Natalya; Mikhailova, Arina; Vlasov, Timur; Samochernykh, Konstantin; Karonova, Tatiana. (2024). SGLT-2 Inhibitors' and GLP-1 Receptor Agonists' Influence on Neuronal and Glial Damage in Experimental Stroke.. Biomedicines, 12(12). https://doi.org/10.3390/biomedicines12122797