American Society of Hirudotherapy

The beneficial roles of metformin on the brain with cerebral ischaemia/reperfusion injury

Review published in Pharmacological research (2019)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Narrative reviewDrug DevelopmentLeech T et al. · Pharmacological research, 2019

Abstract

Cerebral ischaemia/reperfusion (I/R) injury is the transient loss, followed by rapid return, of blood flow to the brain. This condition is often caused by strokes and heart attacks. The underlying mechanisms resulting in brain damage during cerebral I/R injury include mitochondrial dysregulation, increased oxidative stress/reactive oxygen species, blood-brain-barrier breakdown, inflammation of the brain, and increased neuronal apoptosis. Metformin is the first-line antidiabetic drug which has recently been shown to be capable of acting through the aforementioned pathways to improve recovery following cerebral I/R injury. However, some studies have suggested that metformin therapy may have no effect or even worsen recovery following cerebral I/R injury. The present review will compile and examine the available in vivo, in vitro, and clinical data concerning the neuroprotective effects of metformin following cerebral I/R injury. Any contradictory evidence will also be assessed and presented to determine the actual effectiveness of metformin treatment in stroke recovery.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticleResearch Support, Non-U.S. Gov'tReview
Indexed MeSH termsAnimalsApoptosisBrainBrain IschemiaDiabetes MellitusHumansHypoglycemic AgentsMetforminNeuronsNeuroprotective AgentsOxidative StressReperfusion Injury

Summary

Cerebral ischaemia/reperfusion (I/R) injury is the transient loss, followed by rapid return, of blood flow to the brain.

Why This Matters for Hirudotherapy

This review compiled and examined available in vivo, in vitro, and clinical data on the neuroprotective effects of metformin following cerebral ischemia/reperfusion injury, including mechanisms involving mitochondrial dysregulation, oxidative stress, blood-brain barrier breakdown, inflammation, and apoptosis. The review also noted contradictory evidence suggesting metformin may have no effect or worsen outcomes. Caveat: this review makes no mention of leeches, hirudin, leech therapy, or the leech secretome; it has no identifiable relevance to hirudotherapy or ASH's domain.

Citation

The beneficial roles of metformin on the brain with cerebral ischaemia/reperfusion injury

Leech T et al. · Pharmacological research, 2019

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

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