Minocycline Inhibits Microglial Activation and Improves Visual Function in a Chronic Model of Age-Related Retinal
Xuan Du1, Eimear M Byrne1, Mei Chen1
1The Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Sciences, Queen's University, Belfast BT9 7BL, UK.
Abstract:
Age-related macular degeneration (AMD) is a chronic disease, which progresses slowly from early to late stages over many years. Inflammation critically contributes to the pathogenesis of AMD. Here, we investigated the therapeutic potential of minocycline in a chronic model of AMD (i.e., the LysMCre-Socs3 double knockout [DKO] mice). Five-month-old DKO and wild type (WT) (Socs3) mice were gavage fed with minocycline (25 mg/kg daily) or vehicle (distilled water) for 3 months. At the end of the treatment, visual function and retinal changes were examined clinically (using electroretinography, fundus photograph and optic coherence tomography) and immunohistologically. Three months of minocycline treatment did not affect the body weight, behaviour and general health of WT and DKO mice. Minocycline treatment enhanced the a-/b-wave aptitudes and increased retinal thickness in both WT and DKO. DKO mouse retina expressed higher levels of Il1b, CD68 and CD86 and had mild microglial activation, and decreased numbers of arrestin+ photoreceptors, PKCα+ and secretagogin+ bipolar cells compared to WT mouse retina. Minocycline treatment reduced microglial activation and rescued retinal neuronal loss in DKO mice. Our results suggest that long-term minocycline treatment is safe and effective in controlling microglial activation and preserving visual function in chronic models of AMD.
Insights
Minocycline treatment safely reduced inflammation and preserved vision in a mouse model of age-related macular degeneration (AMD). This study shows minocycline
Area of Science:
- Ophthalmology
- Neuroscience
- Immunology
Background:
- Age-related macular degeneration (AMD) is a chronic, slowly progressing retinal disease.
- Inflammation plays a critical role in the pathogenesis of AMD.
Purpose of the Study:
- To investigate the therapeutic potential of minocycline in a chronic mouse model of AMD.
- To evaluate minocycline's effects on visual function and retinal changes.
Main Methods:
- DKO and WT mice were treated with minocycline or vehicle for 3 months.
- Visual function was assessed using electroretinography, fundus photography, and OCT.
- Retinal changes were examined immunohistologically, focusing on microglial activation and neuronal markers.
Main Results:
- Minocycline treatment did not affect general health or body weight.
- Minocycline enhanced visual function (a-/b-wave amplitudes) and increased retinal thickness.
- Minocycline reduced microglial activation and rescued neuronal loss in DKO mice, which exhibit AMD-like pathology.
Conclusions:
- Long-term minocycline treatment is safe and effective in managing microglial activation.
- Minocycline demonstrates therapeutic potential for preserving visual function in chronic AMD models.
