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This study aimed to develop and evaluate a guinea pig model for glaucoma, comparing resultant eyeball enlargement with an existing myopia model. Thirty guinea pigs underwent intracameral injection of magnetic microspheres to induce chronic ocular hypertension (COH). Intraocular pressure (IOP) was systematically monitored, revealing a successful induction of COH in 73.33% of the guinea pigs. The mean IOP increased from a baseline of 18.04 ± 1.33 mmHg, reaching a peak at week 3 (36.31 ± 6.13 mmHg) and remaining elevated for at least 7 weeks. All data are presented as mean ± standard deviation of the mean. Subsequently, detailed assessments were conducted to validate the established glaucoma model. Immunofluorescent staining demonstrated a significant decrease in the density of retinal ganglion cells (RGC) in the glaucoma group. Optic disc excavation and notable thinning of the lamina cribrosa (LC) were observed. The quantity of optic nerve ax·ons in glaucoma group gradually decreased from baseline (44553 ± 3608/mm 2 ) to week 4 (28687 ± 2071/mm 2 ) and week 8 (17977 ± 3697/mm 2 ). Moreover, regarding the global enlargement of eyeballs, both the transverse and longitudinal axis in glaucomatous eyes were found to be significantly larger than that in myopic eyes, particularly in the anterior chamber depth (1.758 ± 0.113 mm vs. 1.151 ± 0.046 mm). These findings indicate distinct patterns of structural changes associated with glaucoma and myopia in the guinea pig model. This guinea pig model holds promise for future research aimed at exploring biomechanical mechanisms, therapeutic interventions, and advancing our understanding of the relationship between glaucoma and myopia., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The carbonic anhydrase 2 (Car2) gene encodes the primary isoenzyme responsible for aqueous humor (AH) production and plays a major role in the regulation of intraocular pressure (IOP). The CRISPR-Cas9 system, based on the ShH10 adenovirus-associated virus, can efficiently disrupt the Car2 gene in the ciliary body. With a single intravitreal injection, Car2 knockout can significantly and sustainably reduce IOP in both normal mice and glaucoma models by inhibiting AH production. Furthermore, it effectively delays and even halts glaucomatous damage induced by prolonged high IOP in a chronic ocular hypertension model, surpassing the efficacy of clinically available carbonic anhydrase inhibitors such as brinzolamide. The clinical application of CRISPR-Cas9 based disruption of Car2 is an attractive therapeutic strategy that could bring additional benefits to patients with glaucoma., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Glaucoma is a common neurodegenerative disease and a leading cause of irreversible blindness worldwide. Retinal microglia-mediated neuroinflammation is involved in the process of optic nerve damage, but the mechanisms driving this microglial activation remain mostly elusive. Previous investigations reported that microRNAs are associated with the retinal microglial reaction and neural apoptosis. In the present study, we found that microRNA-93-5p (miR-93) played a key role in the reaction of retinal microglial cells in vivo and in vitro. The miR-93 level was significantly reduced in the retinae of rat acute ocular hypertension (AOH) models, which were accompanied by retinal microglial activation, overproduction of inflammatory cytokines, and subsequent retinal ganglion cells (RGCs) death, versus the retinae of controls. The induction of miR-93 overexpression significantly reduced microglial proliferation, migration and cytokine release, inhibited the expression of the target gene signal transducer and activator of transcription 3 (STAT3) and p-STAT3, and was associated with a reduced loss of RGCs. Treatment with a STAT3 inhibitor also decreased retinal microglial activation after AOH injury. Taken together, these results suggest that the miR-93/STAT3 pathway is directly related to the downregulation of retinal microglia-mediated neuro-inflammation and showed a neuroprotective effect. Regulating microglial activation through miR-93 may serve as a target for neuroprotective therapy in pathological ocular hypertension.