Bilateral, Simultaneous Central Serous Chorioretinopathy in Association With Oral Contraception Use.

This report describes a case of bilateral, simultaneous central serous chorioretinopathy (CSCR) in a young woman on oral contraceptive pills (OCP). A 21-year-old woman with a negative past medical history presented with sudden onset of bilateral decreased vision shortly after starting OCP. Comprehensive ocular examination revealed bilateral central serous chorioretinopathy (CSCR), confirmed on retinal optical coherence tomography (OCT) and intravenous fluorescein angiography. The patient was instructed to discontinue OCP, and three weeks later, there was complete resolution of the visual symptoms and of the bilateral serous retinal detachments, documented on OCT. [Ophthalmic Surg Lasers Imaging Retina 2024;55:96-99.].

A novel calpain inhibitor for treatment of transient retinal ischemia in the rat.

After an acute ischemia/reperfusion of the rat retina, the activation of cytotoxic proteases, including calpain, results in necrosis and apoptosis of retinal ganglion cells resulting in their degeneration. Using a systemically administered calpain inhibitor that crosses the blood-retinal barrier would provide for novel systemic intervention that protects the retina from acute injury and loss of function. Herein, we study a novel calpain peptide inhibitor, cysteic-leucyl-argininal (CYLA), in an in-vivo rat model of retinal ischemia to determine functional protection using electroretinography. The CYLA prodrug was administered intraperitoneally before and/or after ischemia-reperfusion at concentrations of 20-40 mg/kg. We found that administering 20 mg/kg of CYLA only after ischemia provides significant preservation of retinal function.

Deleterious role of TNF-alpha in retinal ischemia-reperfusion injury.

PURPOSE: Tumor necrosis factor (TNF)-alpha is a mediator of neuronal cell death and survival in ischemia-reperfusion injury. This study was conducted to further elucidate the role of TNF-alpha and its receptor in an in vivo model of retinal ischemia-reperfusion injury by investigating its effects on retinal histopathology and function. METHODS: Retinal ischemia-reperfusion injury was performed on p55 and p75 knockout (KO) mice and Sprague-Dawley rats using the high intraocular pressure METHOD: The temporal expression of TNF-alpha was ascertained with immunohistochemical staining. Separate rats received intravitreal recombinant TNF-alpha or neutralizing antibody before or after ischemia. TUNEL labeling was performed to assess for cell death, and electroretinography was performed to assess function. RESULTS: TNF-alpha expression peaked at 12 to 24 hours after ischemia-reperfusion injury. TUNEL staining was diminished after intravitreal TNF-alpha antibody. Both transgenic KOs demonstrated significantly less functional impairment. Rats receiving recombinant TNF-alpha 48 hours after ischemia showed exaggerated functional impairment. Animals treated with TNF-alpha antibody before ischemia displayed significant functional improvement. CONCLUSIONS: TNF-alpha plays a largely deleterious role in ischemia-reperfusion injury in an in vivo model of retinal injury. Direct neutralization of this cytokine partially preserves retinal function. The diverse characteristics of TNF-alpha are attributed in part to the timing of its expression after injury. TNF-alpha receptor expression and function, along with combination treatments targeting death receptor-mediated apoptosis, should be further explored to develop neuroprotective therapeutic strategies for acute retinal ischemic disorders.

Ischemic preconditioning attenuates apoptotic cell death in the rat retina.

PURPOSE: Ischemic preconditioning (IPC) protects the rat retina against the injury that ordinarily follows prolonged ischemia. It has been shown that release of adenosine, de novo protein synthesis, and mediators, such as protein kinase C and K(ATP) channels, is required for IPC protection. However, the molecular mechanisms of neuroprotection by IPC are unknown. Retinal cells die after ischemia by necrosis and apoptosis. This study was undertaken to investigate the effect of IPC on apoptosis after ischemia and some of the key proteins involved in the apoptotic cascade. METHODS: Retinal ischemia or IPC was produced in anesthetized Sprague-Dawley rats by increasing intraocular pressure above systolic arterial pressure. Retinal ischemia was induced 24 hours after either IPC or sham IPC. TUNEL staining was used to quantitate the number of cells with DNA fragmentation. The authors examined expression of cleaved forms of caspases-2 and -3, bax, and poly-adenosine diphosphate-ribose-polymerase (PARP) by Western blot analysis for evidence of apoptosis-related gene expression. To examine possible mechanisms of apoptosis after ischemia, the authors studied the expression of mitogen-activated protein kinases (MAP kinases). Functional recovery after ischemia was measured using electroretinography, and retinal histology was examined and quantitated by light microscopy. RESULTS: Positive TUNEL staining, increases in caspase-2 and -3 cleavage, expression of bax and PARP, and activation of MAP kinases were found with ischemia. IPC attenuated these changes, but paradoxically, IPC itself triggered increased expression of MAP kinases. CONCLUSIONS: IPC protects against ischemic injury, in part, by diminishing apoptosis-related gene expression and by altering protein phosphorylation.