Beyond Glycemic Control: Metformin's Multi-Target Role in Preventing and Treating Major Ocular Pathologies
Ziyang Liu1, Hongyu Li1, Chuyao Wang1
1Department of Ophthalmology, Affiliated Hospital of Shandong Second Medical University, School of Clinical Medicine, Shandong Second Medical University, Weifang, China.
Summary
Metformin shows potential for various eye conditions beyond diabetes management, but more rigorous research is needed. Current evidence is limited, and further studies must assess safety and effectiveness in ocular tissues.
Area of Science:
- Ophthalmology
- Pharmacology
- Endocrinology
Background:
- Metformin is a primary treatment for type 2 diabetes.
- It exhibits pleiotropic effects beyond glycemic control.
- Emerging evidence suggests potential benefits for various ocular diseases.
Purpose of the Study:
- To review the current evidence on metformin's role in ocular diseases.
- To explore potential mechanisms of action in the eye.
- To identify limitations and future research directions.
Main Methods:
- Review of epidemiological studies and preclinical data.
- Analysis of proposed molecular pathways involved in ocular conditions.
- Evaluation of clinical trial limitations and pharmacokinetic data.
Main Results:
- Observational data suggest metformin may reduce risk or slow progression in diabetic retinopathy, glaucoma, and AMD.
- Preclinical studies indicate modulation of pathways like AMPK-mTOR, autophagy, and inflammation.
- Limited randomized trials exist, with some showing no significant benefit (e.g., METforMIN trial).
- Ocular pharmacokinetics and dose-toxicity relationships are not well-defined.
Conclusions:
- Metformin's ophthalmic applications require further investigation.
- Current evidence is largely observational and requires validation through prospective studies.
- Future research should focus on ocular pharmacokinetics, safety, and efficacy with defined dosing.
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