0000000000403230

AUTHOR

Yue Ruan

Oxidative Stress and Vascular Dysfunction in the Retina: Therapeutic Strategies

Many retinal diseases, such as diabetic retinopathy, glaucoma, and age-related macular (AMD) degeneration, are associated with elevated reactive oxygen species (ROS) levels. ROS are important intracellular signaling molecules that regulate numerous physiological actions, including vascular reactivity and neuron function. However, excessive ROS formation has been linked to vascular endothelial dysfunction, neuron degeneration, and inflammation in the retina. ROS can directly modify cellular molecules and impair their function. Moreover, ROS can stimulate the production of inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) causing inflammation and cel…

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Chronic social defeat stress causes retinal vascular dysfunction

Abstract Purpose The roles of vascular dysfunction and chronic stress have been extensively discussed in the pathophysiology of glaucoma. Our aim was to test whether chronic stress causes retinal vascular dysfunction and therewith induces retinal ganglion cells (RGCs) loss. Methods Twelve mice underwent chronic social defeat (CSD) stress, while 12 mice received control treatment only. Intraocular pressure (IOP) was measured with a rebound tonometer. Blood plasma corticosterone concentration and adrenal gland weight were used to assess stress levels. Brn-3a staining in retinas and PPD staining in optic nerve cross sections were conducted to assess the survival of RGCs and axons respectively.…

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Betulinic Acid Protects from Ischemia-Reperfusion Injury in the Mouse Retina

Ischemia/reperfusion (I/R) events are involved in the pathophysiology of numerous ocular diseases. The purpose of this study was to test the hypothesis that betulinic acid protects from I/R injury in the mouse retina. Ocular ischemia was induced in mice by increasing intraocular pressure (IOP) to 110 mm Hg for 45 min, while the fellow eye served as a control. One group of mice received betulinic acid (50 mg/kg/day p.o. once daily) and the other group received the vehicle solution only. Eight days after the I/R event, the animals were killed and the retinal wholemounts and optic nerve cross-sections were prepared and stained with cresyl blue or toluidine blue, respectively, to count cells in…

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Aircraft noise exposure drives the activation of white blood cells and induces microvascular dysfunction in mice

Epidemiological studies showed that traffic noise has a dose-dependent association with increased cardiovascular morbidity and mortality. Whether microvascular dysfunction contributes significantly to the cardiovascular health effects by noise exposure remains to be established. The connection of inflammation and immune cell interaction with microvascular damage and functional impairment is also not well characterized. Male C57BL/6J mice or gp91phox−/y mice with genetic deletion of the phagocytic NADPH oxidase catalytic subunit (gp91phox or NOX-2) were used at the age of 8 weeks, randomly instrumented with dorsal skinfold chambers and exposed or not exposed to aircraft noise for 4 days. Pro…

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The Role of Adrenoceptors in the Retina

The retina is a part of the central nervous system, a thin multilayer with neuronal lamination, responsible for detecting, preprocessing, and sending visual information to the brain. Many retinal diseases are characterized by hemodynamic perturbations and neurodegeneration leading to vision loss and reduced quality of life. Since catecholamines and respective bindings sites have been characterized in the retina, we systematically reviewed the literature with regard to retinal expression, distribution and function of alpha1 (α1)-, alpha2 (α2)-, and beta (β)-adrenoceptors (ARs). Moreover, we discuss the role of the individual adrenoceptors as targets for the treatment of retinal diseases.

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In vivo analysis of noise dependent activation of white blood cells and microvascular dysfunction in mice

This article contains supporting information on data collection for the research article entitled “Aircraft noise exposure drives the activation of white blood cells and induces microvascular dysfunction in mice” by Eckrich et al. We found that noise-induced stress triggered microvascular dysfunction via involvement of innate immune-derived reactive oxygen species. In this article, we present the instrumentation of mice with dorsal skinfold chambers for in vivo microscopic imaging of blood flow, interaction of leukocytes with the vascular wall (also by fluorescent labelling of blood cells) and vessel diameter. In addition, we explain the preparation of cerebral arterioles for measurement of…

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Corneal Epithelial Stem Cells-Physiology, Pathophysiology and Therapeutic Options.

In the human cornea, regeneration of the epithelium is regulated by the stem cell reservoir of the limbus, which is the marginal region of the cornea representing the anatomical and functional border between the corneal and conjunctival epithelium. In support of this concept, extensive limbal damage, e.g., by chemical or thermal injury, inflammation, or surgery, may induce limbal stem cell deficiency (LSCD) leading to vascularization and opacification of the cornea and eventually vision loss. These acquired forms of limbal stem cell deficiency may occur uni- or bilaterally, which is important for the choice of treatment. Moreover, a variety of inherited diseases, such as congenital aniridia…

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Aged Mice Devoid of the M3 Muscarinic Acetylcholine Receptor Develop Mild Dry Eye Disease

The parasympathetic nervous system is critically involved in the regulation of tear secretion by activating muscarinic acetylcholine receptors. Hence, various animal models targeting parasympathetic signaling have been developed to induce dry eye disease (DED). However, the muscarinic receptor subtype (M1–M5) mediating tear secretion remains to be determined. This study was conducted to test the hypothesis that the M3 receptor subtype regulates tear secretion and to evaluate the ocular surface phenotype of mice with targeted disruption of the M3 receptor (M3R−/−). The experimental techniques included quantification of tear production, fluorescein staining of the ocular surface, environmenta…

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