Correlation between Retinal Ganglion Cell Loss and Nerve Crush Force-Impulse Established with Instrumented Tweezers in Mice

AbstractObjectivesRodent models of optic nerve crush (ONC) have often been used to study degeneration and regeneration of retinal ganglion cells (RGCs) and their axons as well as the underlying molecular mechanisms. However, ONC results from different laboratories exhibit a range of RGC injury with varying degree of axonal damage. We developed an instrumented tweezers to measure optic nerve (ON) crush forces in real time and studied the correlation between RGC axon loss and force-impulse, the product of force and duration, applied through the instrumented tweezers in mice.MethodsA pair of standard self-closing #N7 tweezers were instrumented with miniature foil strain gauges at optimal locations on both tweezer arms. The instrumented tweezers were capable of recording the tip closure forces in the form of voltages, which were calibrated through load cells to corresponding tip closure forces over the operating range. Using the instrumented tweezers, the ONs of multiple mice were crushed with varied forces and durations and the axons in the immunostained sections of the crushed ONs were counted.ResultsWe found that the surviving axon density correlated with crush force, with longer duration and stronger crush forces producing consistently more axon damage.DiscussionThe instrumented tweezers enable a simple technique for measurement of ONC forces in real-time for the first time. Using the instrumented tweezers, experimenters can quantify crush forces during ONC to produce consistent and predictable post-crush cell death. This should permit future studies a way to produce nerve damage more consistently than is available now.

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Repulsive Environment Attenuation during Adult Mouse Optic Nerve Regeneration

Neural Plasticity ◽

10.1155/2018/5851914 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Camila Oliveira Goulart ◽

Henrique Rocha Mendonça ◽

Julia Teixeira Oliveira ◽

Laura Maria Savoldi ◽

Luiza dos Santos Heringer ◽

...

Keyword(s):

Optic Nerve ◽

Axonal Regeneration ◽

Adult Mouse ◽

Ganglion Cells ◽

Combined Therapy ◽

Nerve Fibers ◽

Retinal Ganglion ◽

Nerve Crush ◽

Conditional Deletion ◽

First Time

The regenerative capacity of CNS tracts has ever been a great hurdle to regenerative medicine. Although recent studies have described strategies to stimulate retinal ganglion cells (RGCs) to regenerate axons through the optic nerve, it still remains to be elucidated how these therapies modulate the inhibitory environment of CNS. Thus, the present work investigated the environmental content of the repulsive axon guidance cues, such as Sema3D and its receptors, myelin debris, and astrogliosis, within the regenerating optic nerve of mice submitted to intraocular inflammation + cAMP combined to conditional deletion of PTEN in RGC after optic nerve crush. We show here that treatment was able to promote axonal regeneration through the optic nerve and reach visual targets at twelve weeks after injury. The Regenerating group presented reduced MBP levels, increased microglia/macrophage number, and reduced astrocyte reactivity and CSPG content following optic nerve injury. In addition, Sema3D content and its receptors are reduced in the Regenerating group. Together, our results provide, for the first time, evidence that several regenerative repulsive signals are reduced in regenerating optic nerve fibers following a combined therapy. Therefore, the treatment used made the CNS microenvironment more permissive to regeneration.

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Melatonin As a Modulator of Degenerative and Regenerative Signaling Pathways in Injured Retinal Ganglion Cells

Current Pharmaceutical Design ◽

10.2174/1381612825666190829151314 ◽

2019 ◽

Vol 25 (28) ◽

pp. 3057-3073 ◽

Cited By ~ 6

Author(s):

Kobra B. Juybari ◽

Azam Hosseinzadeh ◽

Habib Ghaznavi ◽

Mahboobeh Kamali ◽

Ahad Sedaghat ◽

...

Keyword(s):

Optic Nerve ◽

Mitochondrial Dysfunction ◽

Signaling Pathways ◽

Retinal Ganglion Cells ◽

Molecular Mechanisms ◽

Nitrosative Stress ◽

Ganglion Cells ◽

Axon Growth ◽

Nerve Fibers ◽

Retinal Ganglion

Optic neuropathies refer to the dysfunction or degeneration of optic nerve fibers caused by any reasons including ischemia, inflammation, trauma, tumor, mitochondrial dysfunction, toxins, nutritional deficiency, inheritance, etc. Post-mitotic CNS neurons, including retinal ganglion cells (RGCs) intrinsically have a limited capacity for axon growth after either trauma or disease, leading to irreversible vision loss. In recent years, an increasing number of laboratory evidence has evaluated optic nerve injuries, focusing on molecular signaling pathways involved in RGC death. Trophic factor deprivation (TFD), inflammation, oxidative stress, mitochondrial dysfunction, glutamate-induced excitotoxicity, ischemia, hypoxia, etc. have been recognized as important molecular mechanisms leading to RGC apoptosis. Understanding these obstacles provides a better view to find out new strategies against retinal cell damage. Melatonin, as a wide-spectrum antioxidant and powerful freeradical scavenger, has the ability to protect RGCs or other cells against a variety of deleterious conditions such as oxidative/nitrosative stress, hypoxia/ischemia, inflammatory processes, and apoptosis. In this review, we primarily highlight the molecular regenerative and degenerative mechanisms involved in RGC survival/death and then summarize the possible protective effects of melatonin in the process of RGC death in some ocular diseases including optic neuropathies. Based on the information provided in this review, melatonin may act as a promising agent to reduce RGC death in various retinal pathologic conditions.

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Axons of retinal ganglion cells are insulted in the optic nerve early in DBA/2J glaucoma

The Journal of Cell Biology ◽

10.1083/jcb.200706181 ◽

2007 ◽

Vol 179 (7) ◽

pp. 1523-1537 ◽

Cited By ~ 285

Author(s):

Gareth R. Howell ◽

Richard T. Libby ◽

Tatjana C. Jakobs ◽

Richard S. Smith ◽

F. Campbell Phalan ◽

...

Keyword(s):

Optic Nerve ◽

Mouse Model ◽

Retinal Ganglion Cells ◽

Strong Evidence ◽

Ganglion Cells ◽

Lamina Cribrosa ◽

Retinal Ganglion ◽

Rich Region ◽

Pattern Electroretinography ◽

Axon Damage

Here, we use a mouse model (DBA/2J) to readdress the location of insult(s) to retinal ganglion cells (RGCs) in glaucoma. We localize an early sign of axon damage to an astrocyte-rich region of the optic nerve just posterior to the retina, analogous to the lamina cribrosa. In this region, a network of astrocytes associates intimately with RGC axons. Using BAX-deficient DBA/2J mice, which retain all of their RGCs, we provide experimental evidence for an insult within or very close to the lamina in the optic nerve. We show that proximal axon segments attached to their cell bodies survive to the proximity of the lamina. In contrast, axon segments in the lamina and behind the eye degenerate. Finally, the Wlds allele, which is known to protect against insults to axons, strongly protects against DBA/2J glaucoma and preserves RGC activity as measured by pattern electroretinography. These experiments provide strong evidence for a local insult to axons in the optic nerve.

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Optical Detection of Early Damage in Retinal Ganglion Cells in a Mouse Model of Partial Optic Nerve Crush Injury

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.16-19955 ◽

2016 ◽

Vol 57 (13) ◽

pp. 5665 ◽

Cited By ~ 12

Author(s):

Ji Yi ◽

Zhen Puyang ◽

Liang Feng ◽

Lian Duan ◽

Peiji Liang ◽

...

Keyword(s):

Optic Nerve ◽

Mouse Model ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Crush Injury ◽

Optic Nerve Crush ◽

Retinal Ganglion ◽

Nerve Crush ◽

Early Damage ◽

Nerve Crush Injury

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Nerve fibre layer degeneration and retinal ganglion cell loss long term after optic nerve crush or transection in adult mice

Experimental Eye Research ◽

10.1016/j.exer.2018.02.010 ◽

2018 ◽

Vol 170 ◽

pp. 40-50 ◽

Cited By ~ 19

Author(s):

M.C. Sánchez-Migallón ◽

F.J. Valiente-Soriano ◽

M. Salinas-Navarro ◽

F.M. Nadal-Nicolás ◽

M. Jiménez-López ◽

...

Keyword(s):

Optic Nerve ◽

Ganglion Cell ◽

Nerve Fibre ◽

Cell Loss ◽

Optic Nerve Crush ◽

Retinal Ganglion ◽

Nerve Crush ◽

Adult Mice ◽

Nerve Fibre Layer

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Axon Regeneration in the Mammalian Optic Nerve

Annual Review of Vision Science ◽

10.1146/annurev-vision-022720-094953 ◽

2020 ◽

Vol 6 (1) ◽

pp. 195-213

Author(s):

Philip R. Williams ◽

Larry I. Benowitz ◽

Jeffrey L. Goldberg ◽

Zhigang He

Keyword(s):

Optic Nerve ◽

Ganglion Cells ◽

Traumatic Injury ◽

Optic Glioma ◽

Retinal Ganglion ◽

Degenerative Diseases ◽

Nerve Crush ◽

Neural Repair ◽

Molecular Logic ◽

Injury Models

The damage or loss of retinal ganglion cells (RGCs) and their axons accounts for the visual functional defects observed after traumatic injury, in degenerative diseases such as glaucoma, or in compressive optic neuropathies such as from optic glioma. By using optic nerve crush injury models, recent studies have revealed the cellular and molecular logic behind the regenerative failure of injured RGC axons in adult mammals and suggested several strategies with translational potential. This review summarizes these findings and discusses challenges for developing clinically applicable neural repair strategies.

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Wogonin prevents TLR4-NF-κB-medicated neuro-inflammation and improves retinal ganglion cells survival in retina after optic nerve crush

Oncotarget ◽

10.18632/oncotarget.12700 ◽

2016 ◽

Vol 7 (45) ◽

pp. 72503-72517 ◽

Cited By ~ 20

Author(s):

Yue Xu ◽

Boyu Yang ◽

Yaguang Hu ◽

Lin Lu ◽

Xi Lu ◽

...

Keyword(s):

Optic Nerve ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Optic Nerve Crush ◽

Retinal Ganglion ◽

Nerve Crush ◽

Neuro Inflammation

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A second episode of ganglion cell death takes place when an optic nerve regenerates for a second time in the frog

Visual Neuroscience ◽

10.1017/s0952523800003692 ◽

1993 ◽

Vol 10 (2) ◽

pp. 297-301 ◽

Cited By ~ 7

Author(s):

L. D. Beazley ◽

J.E. Darby

Keyword(s):

Cell Death ◽

Optic Nerve ◽

Ganglion Cell ◽

Ganglion Cells ◽

Cresyl Violet ◽

Retinal Ganglion ◽

Nerve Crush ◽

Optic Nerve Regeneration ◽

Ability To Regenerate ◽

Ganglion Cell Death

AbstractWe have previously reported that during optic nerve regeneration in the frog, 30–40% of retinal ganglion cells die, the loss being complete within 10 weeks. In the present study, we crushed the optic nerve, waited 10 weeks, and then recrushed the nerve at the same site. Retinae were examined 10 weeks later. We estimated ganglion cell numbers from cresyl-violet-stained wholemounts and found a fall of 53% compared to normals. The loss was significantly greater than the losses of 36% and 35%, respectively, in frogs which received a single optic nerve crush and were examined 10 or 20–24 weeks later. The results indicate that a second episode of ganglion cell death took place when the optic nerve regenerated a second time. We conclude that ganglion cells in the frog are not comprised of two subpopulations, only one of which intrinsically possesses the ability to regenerate.

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