0000000000348911
AUTHOR
Caroline Manicam
showing 16 related works from this author
Preparation Steps for Measurement of Reactivity in Mouse Retinal Arterioles <em>Ex Vivo</em>
2018
Vascular insufficiency and alterations in normal retinal perfusion are among the major factors for the pathogenesis of various sight-threatening ocular diseases, such as diabetic retinopathy, hypertensive retinopathy, and possibly glaucoma. Therefore, retinal microvascular preparations are pivotal tools for physiological and pharmacological studies to delineate the underlying pathophysiological mechanisms and to design therapies for the diseases. Despite the wide use of mouse models in ophthalmic research, studies on retinal vascular reactivity are scarce in this species. A major reason for this discrepancy is the challenging isolation procedures owing to the small size of these retinal blo…
Bioenergetic shift and actin cytoskeleton remodelling as acute vascular adaptive mechanisms to angiotensin II in murine retina and ophthalmic artery
2020
Ocular vascular dysfunction is a major contributing factor to the pathogenesis of glaucoma. In recent years, there has been a renewed interest in the role of angiotensin II (Ang II) in mediating the disease progression. Despite its (patho)physiological importance, the molecular mechanisms underlying Ang II-mediated oxidative stress remain largely unexplored in the ocular vasculature. Here, we provide the first direct evidence of the alterations of proteome and signalling pathways underlying Ang II-elicited oxidative insult independent of arterial pressure changes in the ophthalmic artery (OA) and retina (R) employing an in vitro experimental model. Both R and OA were isolated from male C57B…
Enhanced autophagic-lysosomal activity and increased BAG3-mediated selective macroautophagy as adaptive response of neuronal cells to chronic oxidati…
2019
Oxidative stress and a disturbed cellular protein homeostasis (proteostasis) belong to the most important hallmarks of aging and of neurodegenerative disorders. The proteasomal and autophagic-lysosomal degradation pathways are key measures to maintain proteostasis. Here, we report that hippocampal cells selected for full adaptation and resistance to oxidative stress induced by hydrogen peroxide (oxidative stress-resistant cells, OxSR cells) showed a massive increase in the expression of components of the cellular autophagic-lysosomal network and a significantly higher overall autophagic activity. A comparative expression analysis revealed that distinct key regulators of autophagy are upregu…
Betulinic Acid Protects from Ischemia-Reperfusion Injury in the Mouse Retina
2021
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…
Role of α1-adrenoceptor subtypes on corneal epithelial thickness and cell proliferation in mice
2018
Adrenergic stimuli are important for corneal epithelial structure and healing. The purpose of the present study was to examine the hypothesis that the lack of a single α1-adrenoceptor (α1-AR) subtype affects corneal epithelial thickness and cell proliferation. Expression levels of α1-AR mRNA were determined in mouse cornea using real-time PCR. In mice devoid of one of the three α1-AR subtypes (α1A-AR−/−, α1B-AR−/−, α1D-AR−/−) and in wild-type controls, thickness of individual corneal layers, the number of epithelial cell layers, and average epithelial cell size were determined in cryosections. Endothelial cell density and morphology were calculated in corneal explants, and epithelial cell p…
Comparison of Two Solid-Phase Extraction (SPE) Methods for the Identification and Quantification of Porcine Retinal Protein Markers by LC-MS/MS
2018
Proper sample preparation protocols represent a critical step for liquid chromatography-mass spectrometry (LC-MS)-based proteomic study designs and influence the speed, performance and automation of high-throughput data acquisition. The main objective of this study was to compare two commercial solid-phase extraction (SPE)-based sample preparation protocols (comprising SOLAµ
Role of the M3 Muscarinic Acetylcholine Receptor Subtype in Murine Ophthalmic Arteries After Endothelial Removal
2014
We tested the hypothesis that the M3 muscarinic acetylcholine receptor subtype mediates cholinergic responses in murine ophthalmic arteries after endothelial removal.Muscarinic receptor gene expression was determined in ophthalmic arteries with intact and with removed endothelium using real-time PCR. To examine the role of the M3 receptor in mediating vascular responses, ophthalmic arteries from M3 receptor-deficient mice (M3R(-/-)) and respective wild-type controls were studied in vitro. Functional studies were performed in nonpreconstricted arteries with either intact or removed endothelium using video microscopy.In endothelium-intact ophthalmic arteries, mRNA for all five muscarinic rece…
Proteomics Reveals the Potential Protective Mechanism of Hydrogen Sulfide on Retinal Ganglion Cells in an Ischemia/Reperfusion Injury Animal Model
2020
Glaucoma is the leading cause of irreversible blindness and is characterized by progressive retinal ganglion cell (RGC) degeneration. Hydrogen sulfide (H2S) is a potent neurotransmitter and has been proven to protect RGCs against glaucomatous injury in vitro and in vivo. This study is to provide an overall insight of H2S&rsquo
Synthetic Polyclonal-Derived CDR Peptides as an Innovative Strategy in Glaucoma Therapy
2019
The pathogenesis of glaucoma is strongly associated with the occurrence of autoimmune-mediated loss of retinal ganglion cells (RGCs) and additionally, recent evidence shows that specific antibody-derived signature peptides are significantly differentially expressed in sera of primary-open angle glaucoma patients (POAG) compared to healthy controls. Synthetically antibody-derived peptides can modulate various effector functions of the immune system and act as antimicrobial or antiviral molecules. In an ex vivo adolescent glaucoma model, this study, for the first time, demonstrates that polyclonal-derived complementarity-determining regions (CDRs) can significantly increase the survival rate …
Longitudinal CSF proteome profiling in mice to uncover the acute and sustained mechanisms of action of rapid acting antidepressant (2R,6R)-hydroxynor…
2021
Delayed onset of antidepressant action is a shortcoming in depression treatment. Ketamine and its metabolite (2R,6R)-hydroxynorketamine (HNK) have emerged as promising rapid-acting antidepressants. However, their mechanism of action remains unknown. In this study, we first described the anxious and depression-prone inbred mouse strain, DBA/2J, as an animal model to assess the antidepressant-like effects of ketamine and HNK in vivo. To decode the molecular mechanisms mediating HNK's rapid antidepressant effects, a longitudinal cerebrospinal fluid (CSF) proteome profiling of its acute and sustained effects was conducted using an unbiased, hypothesis-free mass spectrometry-based proteomics app…
Sample Preparation for Mass-spectrometry-based Proteomics Analysis of Ocular Microvessels
2019
The use of isolated ocular blood vessels in vitro to decipher the pathophysiological state of the eye using advanced technological approaches has greatly expanded our understanding of certain diseases. Mass spectrometry (MS)-based proteomics has emerged as a powerful tool to unravel alterations in the molecular mechanisms and protein signaling pathways in the vascular beds in health and disease. However, sample preparation steps prior to MS analyses are crucial to obtain reproducible results and in-depth elucidation of the complex proteome. This is particularly important for preparation of ocular microvessels, where the amount of sample available for analyses is often limited and thus, pose…
Rapid acting antidepressant (2R,6R)-hydroxynorketamine (HNK) targets glucocorticoid receptor signaling: a longitudinal cerebrospinal fluid proteome s…
2020
AbstractDelayed onset of antidepressant action is a shortcoming in depression treatment. Ketamine and its metabolite (2R,6R)-hydroxynorketamine (HNK) have emerged as promising rapidacting antidepressants. However, their mechanism of action remains unknown. In this study, we first described the anxious and depression-prone inbred mouse strain, DBA/2J, as a animal model to assess the antidepressant-like effects of ketamine and HNK in vivo. To decode the molecular mechanisms mediating HNK’s rapid antidepressant effects, a longitudinal cerebrospinal fluid (CSF) proteome profiling of its acute and sustained effects was conducted using an unbiased, hypothesis-free mass spectrometry-based proteomi…
The α1B-adrenoceptor subtype mediates adrenergic vasoconstriction in mouse retinal arterioles with damaged endothelium
2014
Background and Purpose The α1-adrenoceptor family plays a critical role in regulating ocular perfusion by mediating responses to catecholamines. The purpose of the present study was to determine the contribution of individual α1-adrenoceptor subtypes to adrenergic vasoconstriction of retinal arterioles using gene-targeted mice deficient in one of the three adrenoceptor subtypes (α1A-AR−/−, α1B-AR−/− and α1D-AR−/− respectively). Experimental Approach Using real-time PCR, mRNA expression for individual α1-adrenoceptor subtypes was determined in murine retinal arterioles. To assess the functional relevance of the three α1-adrenoceptor subtypes for mediating vascular responses, retinal vascular…
Role of 1-Adrenoceptor Subtypes in Pupil Dilation Studied With Gene-Targeted Mice
2014
PURPOSE The α₁A-adrenoceptor (α₁A-AR) subtype was suggested to mediate contraction and trophic effects in the iris dilator muscle, and thus its pharmacological blockade may be involved in intraoperative floppy iris syndrome. We tested the hypothesis that the α₁A-AR mediates pupil dilation and trophic effects in the mouse iris. METHODS The α₁-AR subtype mRNA expression was quantified in iris tissue by real-time PCR. To assess the role of individual α₁-ARs for mediating pupil dilation, the α₁-AR agonist phenylephrine was topically applied to the ocular surface of mice deficient in one of the three α₁-AR subtypes (α₁A-AR(-/-), α₁B-AR(-/-), α₁D-AR(-/-), respectively) and wild-type controls. Cha…
Role of nitric oxide synthase isoforms for ophthalmic artery reactivity in mice.
2014
Abstract Nitric oxide synthases (NOS) are involved in regulation of ocular vascular tone and blood flow. While endothelial NOS (eNOS) has recently been shown to mediate endothelium-dependent vasodilation in mouse retinal arterioles, the contribution of individual NOS isoforms to vascular responses is unknown in the retrobulbar vasculature. Moreover, it is unknown whether the lack of a single NOS isoform affects neuron survival in the retina. Thus, the goal of the present study was to examine the hypothesis that the lack of individual nitric oxide synthase (NOS) isoforms affects the reactivity of mouse ophthalmic arteries and neuron density in the retinal ganglion cell (RGC) layer. Mice defi…
Retinal arteriole reactivity in mice lacking the endothelial nitric oxide synthase (eNOS) gene
2018
Dysfunctional vascular endothelial nitric oxide synthase (eNOS) has been proposed to play a main pathophysiological role in various ocular diseases. The aim of the present study was to test the hypothesis that the chronic lack of eNOS impairs endothelium-dependent vasodilation in retinal arterioles. The relevance of eNOS for mediating vascular responses was studied in retinal vascular preparations from eNOS-deficient mice (eNOS-/-) and wild-type controls in vitro. Changes in luminal diameter in response to vasoactive agents were measured by videomicroscopy. The thromboxane mimetic, U46619, induced similar concentration-dependent constriction of retinal arterioles in eNOS-/- and wild-type mi…