AMPA receptor desensitization is the determinant of AMPA receptor mediated excitotoxicity in purified retinal ganglion cells

Park, Yong H.; Mueller, Brett H.; McGrady, Nolan R; Ying, Hai; Yorio, Thomas

doi:10.1016/j.exer.2015.01.026

Cited by 15 publications

(17 citation statements)

References 78 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, a significant decrease was observed in the GD group (66 6 4.4%, P < 0.05) not of the OGD group (85 6 1.5%), when compared to N-RGC Medium group. As observed in our previous findings, 30 the GD-s-AMPA (86 6 2.2 %) or OGD-s-AMPA (85 6 2.3%) did not decrease RGC viability. Interestingly though, RGCs incubated in GD-Precon-s-AMPA (52 6 6.4%; P < 0.001) and OGD-Precon-s-AMPA (22 6 5.1%; P < 0.001) treatments saw an appreciable decrease in RGC survival when compared to N-RGC Medium treatment group.…”

Section: Oxygen/glucose Deprivation Preconditioning Induced Injury Ansupporting

confidence: 71%

“…The RGCs were cultured in serum-free defined medium containing Dulbecco's modified Eagle's medium (DMEM, #11960; Invitrogen), forskolin (5 ng/ mL, #F6886; Sigma-Aldrich Corp.), and two trophic factors: brain-derived neurotrophic factor (BDNF, 50 ng/mL, #450-02; Peprotech, Rocky Hill, NJ, USA) and ciliary neurotrophic factor (CNTF, 10 ng/mL, #450-13; Peprotech). 30,44 This culture medium is designated as ''RGC medium'' throughout the manuscript. Cultures of RGC were maintained in a 378C humidified incubator containing 10% CO 2 .…”

Section: Methods Purified Rgcs Isolation and Culturementioning

confidence: 99%

“…Purified neonatal RGCs were isolated using a double immunopanning technique as published previously. 30,43 Time-pregnant Sprague-Dawley rats were purchased from Charles River (Wilmington, MA, USA), and retinas were dissected from euthanized postnatal (days 4-6) rat pups. Collected retinas were dissociated in papain solution (4.5 units/mL, #3125; Worthington, Lakewood, NJ, USA).…”

Section: Methods Purified Rgcs Isolation and Culturementioning

confidence: 99%

“…All experiments were performed in triplicates, n ¼ 4. ] was determined by the Grynkiewicz equation as described by Park et al 30 Detection of Calcium-Permeable AMPA Receptor Purified RGCs were seeded at a density of 10,000 cells per well. Retinal ganglion cells were treated in either RGC medium, GD, or OGD conditions for 4 hours.…”

Section: Caspase 3/7 Activitymentioning

confidence: 99%

“…24,28,29 These confounding factors make it hard to discern if AMPAR in RGCs are contributing to excitotoxicity directly, or as a secondary effect. In our previous studies, 30 we demonstrated that stimulating AMPAR with s-AMPA (a highly selective agonist) in a purified RGC culture, does not induce excitotoxicity, but instead promotes RGC survival through the induction of cAMP response element-binding protein (CREB) phosphorylation. We concluded that blocking AMPAR's desensitization, like using cyclothiazide, induced RGC death and is the determinant for excitotoxicity.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Involvement of AMPA Receptor and Its Flip and Flop Isoforms in Retinal Ganglion Cell Death Following Oxygen/Glucose Deprivation

Park

Broyles

et al. 2016

Invest. Ophthalmol. Vis. Sci.

Self Cite

View full text Add to dashboard Cite

PURPOSE. The a-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid (AMPA) receptors (AMPAR) subunits can be posttranscriptionally modified by alternative splicing forming flip and flop isoforms. We determined if an ischemia-like insult to retinal ganglion cells (RGCs) increases AMPAR susceptibility to s-AMPA-mediated excitotoxicity through changes in posttranscriptional modified isoforms. METHODS.Purified neonatal rat RGCs were subjected to either glucose deprivation (GD) or oxygen/glucose deprivation (OGD) conditions followed by treatment with either 100 lM s-AMPA or Kainic acid. A live-dead assay and caspase 3 assay was used to assess cell viability and apoptotic changes, respectively. We used JC-1 dye and dihydroethidium to measure mitochondria depolarization and reactive oxygen species (ROS), respectively. Calcium imaging with fura-2AM was used to determine intracellular calcium, while the fluorescentlylabeled probe, Nanoprobe1, was used to detect calcium-permeable AMPARs. Quantitative PCR (qPCR) analysis was done to determine RNA editing sites AMPAR isoforms.RESULTS. Glucose deprivation, as well as an OGD insult followed by AMPAR stimulation, produced a significant increase in RGC death. Retinal ganglion cell death was independent of caspase 3/7 activity, but was accompanied by increased mitochondrial depolarization and increased ROS production. This was associated with an elevated intracellular Ca 2þ and calcium permeable-AMPARs. The mRNA expression of GLUA2 and GLUA3 flop isoform decreased significantly, while no appreciable changes were found in the corresponding flip isoforms. There were no changes in the Q/R editing of GLUA2, while R/G editing of GLUA2 flop declined under these conditions. CONCLUSIONS. Following oxidative injury, RGCs become more susceptible to AMPAR-mediated excitotoxicity. RNA editing and changes in alternative spliced flip and flop isoforms of AMPAR subunits may contribute to increased RGC death.

show abstract

Section: Oxygen/glucose Deprivation Preconditioning Induced Injury Ansupporting

confidence: 71%

Section: Methods Purified Rgcs Isolation and Culturementioning

confidence: 99%

Section: Methods Purified Rgcs Isolation and Culturementioning

confidence: 99%

Section: Caspase 3/7 Activitymentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Involvement of AMPA Receptor and Its Flip and Flop Isoforms in Retinal Ganglion Cell Death Following Oxygen/Glucose Deprivation

Park

Broyles

et al. 2016

Invest. Ophthalmol. Vis. Sci.

Self Cite

View full text Add to dashboard Cite

show abstract

Cell and Animal Models used for Retinal Stem Cell Research

Young

Park

2018

Regenerative Medicine and Stem Cell Therapy for the Eye

View full text Add to dashboard Cite

Upregulation of Homer1a Promoted Retinal Ganglion Cell Survival After Retinal Ischemia and Reperfusion via Interacting with Erk Pathway

Fei

Rao

et al. 2015

Cell Mol Neurobiol

View full text Add to dashboard Cite

Retinal ischemia and reperfusion (I/R) is extensively involved in ocular diseases, causing retinal ganglion cell (RGCs) death resulting in visual impairment and blindness. Homer1a is considered as an endogenous neuroprotective protein in traumatic brain injury. However, the roles of Homer1a in RGCs I/R injury have not been elucidated. The present study investigated the changes in expression and effect of Homer1a in RGCs both in vitro and in vivo after I/R injury using Western blot, TUNEL assay, gene interference and overexpression, and gene knockout procedures. The levels of Homer1a and phosphorylated Erk (p-Erk) increased in RGCs and retinas after I/R injury. Upregulation of Homer1a in RGCs after I/R injury decreased the level of p-Erk, and mitigated RGCs apoptosis. Conversely, downregulation of Homer1a increased the level of p-Erk, and augmented RGCs apoptosis. Furthermore, inhibition of the p-ERK reduced RGCs apoptosis, and increased the expression of Homer 1a after I/R injury. Finally, the retinas of Homer1a KO mice treated with I/R injury had significantly less dendrites and RGCs, compared with Homer1a WT mice. These findings demonstrated that Homer1a may contribute to RGCs survival after I/R injury by interacting with Erk pathway.

show abstract

AMPA receptor desensitization is the determinant of AMPA receptor mediated excitotoxicity in purified retinal ganglion cells

Cited by 15 publications

References 78 publications

Involvement of AMPA Receptor and Its Flip and Flop Isoforms in Retinal Ganglion Cell Death Following Oxygen/Glucose Deprivation

Involvement of AMPA Receptor and Its Flip and Flop Isoforms in Retinal Ganglion Cell Death Following Oxygen/Glucose Deprivation

Cell and Animal Models used for Retinal Stem Cell Research

Upregulation of Homer1a Promoted Retinal Ganglion Cell Survival After Retinal Ischemia and Reperfusion via Interacting with Erk Pathway

Contact Info

Product

Resources

About