Rapid isolation of intact retinal astrocytes: a novel approach DOI Creative Commons
Paul Cullen, Arpan G. Mazumder, Daniel Sun

et al.

Acta Neuropathologica Communications, Journal Year: 2023, Volume and Issue: 11(1)

Published: Sept. 25, 2023

Astrocytes are a major category of glial support cell in the central nervous system and play variety essential roles both health disease. As our understanding diverse functions these cells improves, extent heterogeneity between astrocyte populations has emerged as key area research. Retinal astrocytes, which form direct cellular environment retinal ganglion somas axons, undergo reactive response human glaucoma animal models disease, yet their contributions to its pathology progression remain relatively unknown. This gap knowledge is largely function inadequate isolation techniques, driven part by sparseness similarities with more abundant Müller cells. Here, we present novel method isolating astrocytes enriching RNA, tested normal ocular hypertensive mice, common model experimental glaucoma. Our approach combines enzyme assisted microdissection selective ribosome immunoprecipitation using Ribotag method. rapid preserves morphology, resulting brief post-mortem interval minimizing loss RNA from distal regions Both require minimum specialized equipment or reagents, them conjunction able achieve > 100-fold enrichment RNA.

Language: Английский

Addressing neurodegeneration in glaucoma: Mechanisms, challenges, and treatments DOI Creative Commons
Ghazi O. Bou Ghanem, Lauren K. Wareham, David J. Calkins

et al.

Progress in Retinal and Eye Research, Journal Year: 2024, Volume and Issue: 100, P. 101261 - 101261

Published: March 26, 2024

Glaucoma is the leading cause of irreversible blindness globally. The disease causes vision loss due to neurodegeneration retinal ganglion cell (RGC) projection brain through optic nerve. associated with sensitivity intraocular pressure (IOP). Thus, mainstay treatments seek manage IOP, though many patients continue lose vision. To address directly, numerous preclinical studies develop protective or reparative therapies that act independently IOP. These include growth factors, compounds targeting metabolism, anti-inflammatory and antioxidant agents, neuromodulators. Despite success in experimental models, these approaches fail translate into clinical benefits. Several factors contribute this challenge. Firstly, anatomic structure nerve head differs between rodents, nonhuman primates, humans. Additionally, animal models do not replicate complex glaucoma pathophysiology Therefore, enhance translating findings, we propose two approaches. First, thorough evaluation targets multiple including should precede trials. Second, advocate for combination therapy, which involves using agents simultaneously, especially early potentially reversible stages disease. strategies aim increase chances successful neuroprotective treatment glaucoma.

Language: Английский

Citations

16
Korean Red ginseng-induced astrocytic HIF-1α: A key regulator of neuroglobin derived from neural stem cell differentiation in physiologic retina and brain DOI Creative Commons

Sunhong Moon,

J.S. Park, Sueun Kim

et al.

Journal of Ginseng Research, Journal Year: 2025, Volume and Issue: 49(2), P. 189 - 196

Published: Jan. 1, 2025

Neuroglobin (Ngb) and growth-associated protein (GAP) 43 in neurons are associated with axonal regeneration. Korean Red Ginseng Extract (KRGE) enhances glial fibrillary acidic (GFAP)-positive astrocytes hypoxia-inducible factor-1α (HIF-1α) activation normoxic astrocytes. However, crosstalk between neural stem cell (NSC) differentiation astrocytic HIF-1α the KRGE-treated brain retina remains unclear. We investigated whether can enhance NSC increase mature expressing Ngb GAP43. Mature neuronal markers such as nuclei (NeuN) or microtubule-associated 2 (MAP2) were tested mouse retinal tissues post-KRGE administration. Direct KRGE treatment of NSCs was evaluated for levels. The astrocyte conditioned media (ACM) transferred to levels reduced using small interfering RNA transfection (si-HIF-1α) si-HIF-1α-ACM differentiation. KRGE-administered mice showed significantly enhanced co-expression NeuN MAP2 retina, along marker Nestin, than water-administered mice. did not NSCs, but stimulated secrete factors affecting NSCs' differentiate into retinas GFAP- double-positive cells. Co-treatment si-HIF-1α-transfected KRGE-ACM blocked KRGE-ACM-induced Ngb-expressing neurons. stimulates HIF-1α, which regulates Ngb, thereby promoting regeneration by enhancing NSC-astrocyte physiological brain.

Language: Английский

Citations

0
Microglial regulation of the retinal vasculature in health and during the pathology associated with diabetes DOI Creative Commons
Andrew I. Jobling, Ursula Greferath, Michael Dixon

et al.

Progress in Retinal and Eye Research, Journal Year: 2025, Volume and Issue: 106, P. 101349 - 101349

Published: Feb. 26, 2025

Language: Английский

Citations

0
Potassium‐Dependent Coupling of Retinal Astrocyte Light Response to Müller Glia DOI Creative Commons
Joseph M. Holden, Andrew M. Boal, Lauren K. Wareham

et al.

Glia, Journal Year: 2025, Volume and Issue: unknown

Published: April 22, 2025

ABSTRACT Astrocytes throughout the central nervous system mediate a variety of functions to support proper tissue physiology, including regulation blood flow and providing metabolic neurons. There is also growing appreciation for their role in directly modulating neuronal excitability information transfer. Recently, we reported that astrocytes retina exhibit an array neuronal‐associated microstructural motifs whose structure placement suggest roles monitoring electrical activity or direct modulation excitability. In this study, record whole‐cell patch clamp responses intact both light voltage step as precursor studying detailed physiology individual motifs. Retinal small amplitude, graded depolarization ON OFF stimuli with waveforms closely resemble those Müller glial endfeet, from which recorded. Depolarization due potassium influx, major source likely being focal release endfeet onto astrocyte soma. Both macroglia additionally share current–voltage relationships stimulus‐dependent changes ionic permeability. The results pathway communication cells could broader retinal beyond spatial buffering.

Language: Английский

Citations

0
Morphological and electrophysiological characterization of a novel displaced astrocyte in the mouse retina DOI Creative Commons
Joseph M. Holden, Lauren K. Wareham, David J. Calkins

et al.

Glia, Journal Year: 2024, Volume and Issue: 72(7), P. 1356 - 1370

Published: April 9, 2024

Abstract Astrocytes throughout the central nervous system are heterogeneous in both structure and function. This diversity leads to tissue‐specific specialization where morphology is adapted surrounding neuronal circuitry, as seen Bergman glia of cerebellum Müller retina. Because can be a differentiating factor for cellular classification, we recently developed mouse glial‐fibrillary acidic protein (GFAP)‐expressing cells stochastically label full membranous morphology. Here utilize this tool investigate whether morphological electrophysiological features separate types retinal astrocytes. In work, report on novel glial population found inner plexiform layer ganglion cell which expresses canonical astrocyte markers GFAP, S100β, connexin‐43, Sox2 Sox9. Apart from their localization, these unique radial distribution. They notably absent mid‐retina but heavily concentrated near optic nerve head, lesser degree peripheral Additionally, distinct fiber astrocytes glia, appearing more similar amacrine cells. Despite structural similarity, lack expression common markers. they do not exhibit action potentials, rather resemble small amplitude, graded depolarization light onset offset. Their structure, expression, physiology, intercellular connections suggest that astrocytic, displaced counterparts layer. As such, refer

Language: Английский

Citations

3
Beyond hypertrophy: Changing views of astrocytes in glaucoma DOI Creative Commons
Melissa Cooper, David J. Calkins

Vision Research, Journal Year: 2024, Volume and Issue: 223, P. 108461 - 108461

Published: July 26, 2024

Astrocytes serve multiple roles in helping to maintain homeostatic physiology of central nervous system tissue, ranging from metabolic support coupling between vascular and neural elements. are especially critical axonal tracts such as the optic nerve, where axons propagate energy-demanding action potentials great distances. In disease, astrocyte remodeling is a dynamic, multifaceted process that often over-simplified states quiescence reactivity. glaucoma, axon degeneration nerve characterized by progressive stages. So too remodeling. Here, using quantitative analysis light electron micrographs myelinated sections DBA/2J mouse model we offer further insight into how organization reflects stages degeneration. This indicates even degenerate, gliosis increases without abject proliferation, similar results retina. Gliosis accompanied reorganization. As expand prior frank degeneration, processes retract extra-axonal space reorient towards edge. After threshold expansion, drop out, distribute more evenly across reflecting gliosis. multi-stage likely local rather than global cues surrounding tissue induce rapid reorganization promote survival extend functionality nerve.

Language: Английский

Citations

3
Transcriptional profiling of retinal astrocytes identifies a specific marker and points to functional specialization DOI
Paul Cullen, William Gammerdinger,

Shannan J. Ho Sui

et al.

Glia, Journal Year: 2024, Volume and Issue: 72(9), P. 1604 - 1628

Published: May 24, 2024

Abstract Astrocyte heterogeneity is an increasingly prominent research topic, and studies in the brain have demonstrated substantial variation astrocyte form function, both between within regions. In contrast, retinal astrocytes are not well understood remain incompletely characterized. Along with optic nerve astrocytes, they responsible for supporting ganglion cell axons improved understanding of their role required. We used a combination microdissection Ribotag immunoprecipitation to isolate ribosome‐associated mRNA from investigate transcriptome, which we also compared populations nerve. Astrocytes these regions transcriptionally distinct, identified retina‐specific genes pathways. Moreover, although share much “classical” gene expression patterns uncovered unexpected variation, including related core functions. additionally transcription factor Pax8 as highly specific marker that populate only surface, but prelaminar region at head. These findings likely contribute revised retina.

Language: Английский

Citations

2
Chronic hyperglycemia alters retinal astrocyte microstructure and uptake of cholera toxin B in a murine model of diabetes DOI Creative Commons
Joseph M. Holden,

Olivia L. Bossardet,

Ghazi O. Bou Ghanem

et al.

Journal of Neurochemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 7, 2024

Abstract Astrocytes are the principle glial cells of central nervous system and play an active role in maintaining proper metabolism surrounding neurons. Because their involvement metabolic control, it is likely that physiology changes response to diseases such as diabetes associated diabetic retinopathy. Here, we investigated whether microstructural astrocyte morphology occur during early stages chronic hyperglycemia may be indicative pathogenic programs. We used MORF3 mice conjunction with streptozotocin‐induced investigate single retinal astrocytes at timepoint disease. report initiate a morphological remodeling program, which depends on both glycemic background presence intravitreal injury, alter amount neuronal‐associated pad bristle motifs. Additionally, increases uptake cholera toxin B, possibly reflecting glycolipid glycoprotein biosynthesis. Chronic coupled injection B also causes extensive leukocyte infiltration into retina. Our results have important clinical relevance current therapies for retinopathy involve pharmaceuticals individuals often poorly controlled blood glucose levels. image

Language: Английский

Citations

1
Adverse effects of CXCR2 deficiency in mice reared under non-gnotobiotic conditions DOI Creative Commons
Mónica García,

Monica S Morales,

Tzushan S. Yang

et al.

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: Oct. 30, 2024

The family of pro-inflammatory and pro-angiogenic chemokines including Interleukin-8 (IL-8, aka CXCL8) its homologues (CXCL1,2,3,5,6, 7) exhibit promiscuous binding activation several G-protein-coupled receptors (i.e., CXCR2, CXCR1, the atypical chemokine receptor (ACKR1)). A high proportion their biological activity is attributed to CXCR2 activation, thus many inhibitors are in clinical trials for chronic diseases. However, inhibition often only investigated acutely these or Cxcr2

Language: Английский

Citations

1
Retinal glia in myopia: current understanding and future directions DOI Creative Commons

Pengfan Chen,

Jing Ji, Xinyi Chen

et al.

Frontiers in Cell and Developmental Biology, Journal Year: 2024, Volume and Issue: 12

Published: Dec. 20, 2024

Myopia, a major public health problem, involves axial elongation and thinning of all layers the eye, including sclera, choroid retina, which defocuses incoming light thereby blurs vision. How various populations glia in retina are involved disorder is unclear. Astrocytes Müller cells provide structural support to retina. Astrogliosis myopia may influence blood oxygen supply, neuronal function, axon diameter, turn affect signal conduction. act as sensor mechanical stretching trigger downstream molecular responses. Microglia, for their part, exhibit reactive morphology elevated response inflammation myopia. This review assesses current knowledge about how involve retinal glia, it explores directions future research into that question.

Language: Английский

Citations

1