Browsing by Author "Jones, Kathryn J."

Now showing 1 - 10 of 24
  • Thumbnail Image
    Item
    Adipose-derived stem cell conditioned medium impacts asymptomatic peripheral neuromuscular denervation in the mutant superoxide dismutase (G93A) transgenic mouse model of amyotrophic lateral sclerosis
    (IOS, 2018-09) Walker, Chandler L.; Meadows, Rena M.; Merfeld-Clauss, Stephanie; Du, Yansheng; March, Keith L.; Jones, Kathryn J.; Biomedical Sciences and Comprehensive Care, School of Dentistry
    Background:Amyotrophic lateral sclerosis (ALS) is devastating, leading to paralysis and death. Disease onset begins pre-symptomatically through spinal motor neuron (MN) axon die-back from musculature at ∼47 days of age in the mutant superoxide dismutase 1 (mSOD1G93A) transgenic ALS mouse model. This period may be optimal to assess potential therapies. We previously demonstrated that post-symptomatic adipose-derived stem cell conditioned medium (ASC-CM) treatment is neuroprotective in mSOD1G93A mice. We hypothesized that early disease onset treatment could ameliorate neuromuscular junction (NMJ) disruption. Objective:To determine whether pre-symptom administration of ASC-CM prevents early NMJ disconnection. Methods:We confirmed the NMJ denervation time course in mSOD1G93A mice using co-labeling of neurofilament and post-synaptic acetylcholine receptors (AchR) by α-bungarotoxin. We determined whether ASC-CM ameliorates early NMJ loss in mSOD1G93A mice by systemically administering 200μl ASC-CM or vehicle medium daily from post-natal days 35 to 47 and quantifying intact NMJs through co-labeling of neurofilament and synaptophysin with α-bungarotoxin in gastrocnemius muscle. Results:Intact NMJs were significantly decreased in 47 day old mSOD1G93A mice (p < 0.05), and daily systemic ASC-CM prevented disease-induced NMJ denervation compared to vehicle treated mice (p < 0.05). Conclusions:Our results lay the foundation for testing the long-term neurological benefits of systemic ASC-CM therapy in the mSOD1G93A mouse model of ALS.
  • Thumbnail Image
    Item
    Axotomy-induced target disconnection promotes an additional death mechanism involved in motoneuron degeneration in amyotrophic lateral sclerosis transgenic mice
    (Wiley, 2014-07) Haulcomb, Melissa M.; Mesnard, Nichole A.; Batka, Richard J.; Alexander, Thomas D.; Sanders, Virginia M.; Jones, Kathryn J.; Department of Anatomy & Cell Biology, School of Medicine
    The target disconnection theory of amyotrophic lateral sclerosis (ALS) pathogenesis suggests that disease onset is initiated by a peripheral pathological event resulting in neuromuscular junction loss and motoneuron (MN) degeneration. Presymptomatic mSOD1(G93A) mouse facial MN (FMN) are more susceptible to axotomy-induced cell death than wild-type (WT) FMN, which suggests additional CNS pathology. We have previously determined that the mSOD1 molecular response to facial nerve axotomy is phenotypically regenerative and indistinguishable from WT, whereas the surrounding microenvironment shows significant dysregulation in the mSOD1 facial nucleus. To elucidate the mechanisms underlying the enhanced mSOD1 FMN loss after axotomy, we superimposed the facial nerve axotomy model on presymptomatic mSOD1 mice and investigated gene expression for death receptor pathways after target disconnection by axotomy vs. disease progression. We determined that the TNFR1 death receptor pathway is involved in axotomy-induced FMN death in WT and is partially responsible for the mSOD1 FMN death. In contrast, an inherent mSOD1 CNS pathology resulted in a suppressed glial reaction and an upregulation in the Fas death pathway after target disconnection. We propose that the dysregulated mSOD1 glia fail to provide support the injured MN, leading to Fas-induced FMN death. Finally, we demonstrate that, during disease progression, the mSOD1 facial nucleus displays target disconnection-induced gene expression changes that mirror those induced by axotomy. This validates the use of axotomy as an investigative tool in understanding the role of peripheral target disconnection in the pathogenesis of ALS.
  • Thumbnail Image
    Item
    CD4+ T cell expression of the IL-10 receptor is necessary for facial motoneuron survival after axotomy
    (BMC, 2020) Runge, Elizabeth M.; Iyer, Abhirami K.; Setter, Deborah O.; Kennedy, Felicia M.; Sanders, Virginia M.; Jones, Kathryn J.; Anatomy and Cell Biology, School of Medicine
    Background: After peripheral nerve transection, facial motoneuron (FMN) survival depends on an intact CD4+ T cell population and a central source of interleukin-10 (IL-10). However, it has not been determined previously whether CD4+ T cells participate in the central neuroprotective IL-10 cascade after facial nerve axotomy (FNA). Methods: Immunohistochemical labeling of CD4+ T cells, pontine vasculature, and central microglia was used to determine whether CD4+ T cells cross the blood-brain barrier and enter the facial motor nucleus (FMNuc) after FNA. The importance of IL-10 signaling in CD4+ T cells was assessed by performing adoptive transfer of IL-10 receptor beta (IL-10RB)-deficient CD4+ T cells into immunodeficient mice prior to injury. Histology and qPCR were utilized to determine the impact of IL-10RB-deficient T cells on FMN survival and central gene expression after FNA. Flow cytometry was used to determine whether IL-10 signaling in T cells was necessary for their differentiation into neuroprotective subsets. Results: CD4+ T cells were capable of crossing the blood-brain barrier and associating with reactive microglial nodules in the axotomized FMNuc. Full induction of central IL-10R gene expression after FNA was dependent on CD4+ T cells, regardless of their own IL-10R signaling capability. Surprisingly, CD4+ T cells lacking IL-10RB were incapable of mediating neuroprotection after axotomy and promoted increased central expression of genes associated with microglial activation, antigen presentation, T cell co-stimulation, and complement deposition. There was reduced differentiation of IL-10RB-deficient CD4+ T cells into regulatory CD4+ T cells in vitro. Conclusions: These findings support the interdependence of IL-10- and CD4+ T cell-mediated mechanisms of neuroprotection after axotomy. CD4+ T cells may potentiate central responsiveness to IL-10, while IL-10 signaling within CD4+ T cells is necessary for their ability to rescue axotomized motoneuron survival. We propose that loss of IL-10 signaling in CD4+ T cells promotes non-neuroprotective autoimmunity after FNA.
  • Thumbnail Image
    Item
    Cellular Sources and Neuroprotective Roles of Interleukin-10 in the Facial Motor Nucleus after Axotomy
    (MDPI, 2022-10-09) Runge, Elizabeth M.; Setter, Deborah O.; Iyer, Abhirami K.; Regele, Eric J.; Kennedy, Felicia M.; Sanders, Virginia M.; Jones, Kathryn J.; Anatomy, Cell Biology and Physiology, School of Medicine
    Facial motoneuron (FMN) survival is mediated by CD4+ T cells in an interleukin-10 (IL-10)-dependent manner after facial nerve axotomy (FNA), but CD4+ T cells themselves are not the source of this neuroprotective IL-10. The aims of this study were to (1) identify the temporal and cell-specific induction of IL-10 expression in the facial motor nucleus and (2) elucidate the neuroprotective capacity of this expression after axotomy. Immunohistochemistry revealed that FMN constitutively produced IL-10, whereas astrocytes were induced to make IL-10 after FNA. Il10 mRNA co-localized with microglia before and after axotomy, but microglial production of IL-10 protein was not detected. To determine whether any single source of IL-10 was critical for FMN survival, Cre/Lox mouse strains were utilized to selectively knock out IL-10 in neurons, astrocytes, and microglia. In agreement with the localization data reflecting concerted IL-10 production by multiple cell types, no single cellular source of IL-10 alone could provide neuroprotection after FNA. These findings suggest that coordinated neuronal and astrocytic IL-10 production is necessary for FMN survival and has roles in neuronal homeostasis, as well as neuroprotective trophism after axotomy.
  • Thumbnail Image
    Item
    Effects of electrical stimulation and testosterone on regeneration-associated gene expression and functional recovery in a rat model of sciatic nerve crush injury
    (2014) Meadows, Rena Marie; Xu, Xiao-Ming; Chen, Jinhui; Jones, Kathryn J.; White, Fletcher A.
    Although peripheral motoneurons are phenotypically endowed with robust regenerative capacity, functional recovery is often suboptimal following peripheral nerve injury (PNI). Research to date indicates that the greatest success in achieving full functional recovery will require the use of a combinatorial approach that can simultaneously target different aspects of the post-injury response. In general, the concept of a combinatorial approach to neural repair has been established in the scientific literature but has yet to be successfully applied in the clinical situation. Emerging evidence from animal studies supports the use of electrical stimulation (ES) and testosterone as one type of combinatorial treatment after crush injury to the facial nerve (CN VII). With the facial nerve injury model, we have previously demonstrated that ES and testosterone target different stages of the regeneration process and enhance functional recovery after facial nerve crush injury. What is currently unknown, but critical to determine, is the impact of a combinatorial treatment strategy of ES and testosterone on functional recovery after crush injury to the sciatic nerve, a mixed sensory and motor spinal nerve which is one of the most serious PNI clinical problems. The results of the present study indicate that either treatment alone or in combination positively impact motor recovery. With regard to molecular effects,single and combinatorial treatments differentially alter the expression of regeneration-associated genes following sciatic nerve crush injury relative to facial nerve injury. Thus, our data indicate that not all injuries equally respond to treatment. Furthermore, the results support the importance of treatment strategy development in an injury-dependent manner and based upon the functional characteristics of spinal vs. cranial nerves.
  • Thumbnail Image
    Item
    Facial Nerve Axotomy in Mice: A Model to Study Motoneuron Response to Injury
    (2015-02) Olmstead, Deborah N.; Mesnard-Hoaglin, Nichole A.; Batka, Richard J.; Haulcomb, Melissa M.; Miller, Whitney M.; Jones, Kathryn J.; Department of Anatomy & Cell Biology, IU School of Medicine
    The goal of this surgical protocol is to expose the facial nerve, which innervates the facial musculature, at its exit from the stylomastoid foramen and either cut or crush it to induce peripheral nerve injury. Advantages of this surgery are its simplicity, high reproducibility, and the lack of effect on vital functions or mobility from the subsequent facial paralysis, thus resulting in a relatively mild surgical outcome compared to other nerve injury models. A major advantage of using a cranial nerve injury model is that the motoneurons reside in a relatively homogenous population in the facial motor nucleus in the pons, simplifying the study of the motoneuron cell bodies. Because of the symmetrical nature of facial nerve innervation and the lack of crosstalk between the facial motor nuclei, the operation can be performed unilaterally with the unaxotomized side serving as a paired internal control. A variety of analyses can be performed postoperatively to assess the physiologic response, details of which are beyond the scope of this article. For example, recovery of muscle function can serve as a behavioral marker for reinnervation, or the motoneurons can be quantified to measure cell survival. Additionally, the motoneurons can be accurately captured using laser microdissection for molecular analysis. Because the facial nerve axotomy is minimally invasive and well tolerated, it can be utilized on a wide variety of genetically modified mice. Also, this surgery model can be used to analyze the effectiveness of peripheral nerve injury treatments. Facial nerve injury provides a means for investigating not only motoneurons, but also the responses of the central and peripheral glial microenvironment, immune system, and target musculature. The facial nerve injury model is a widely accepted peripheral nerve injury model that serves as a powerful tool for studying nerve injury and regeneration.
  • Thumbnail Image
    Item
    Facial nerve repair utilizing intraoperative repair strategies
    (Wiley, 2020-05-28) Brown, Brandon L.; Sandelski, Morgan M.; Drejet, Sarah M.; Runge, Elizabeth M.; Shipchandler, Taha Z.; Jones, Kathryn J.; Walker, Chandler L.; Radiology and Imaging Sciences, School of Medicine
    Objectives To determine whether functional and anatomical outcomes following suture neurorrhaphy are improved by the addition of electrical stimulation with or without the addition of polyethylene glycol (PEG). Methods In a rat model of facial nerve injury, complete facial nerve transection and repair was performed via (a) suture neurorrhaphy alone, (b) neurorrhaphy with the addition of brief (30 minutes) intraoperative electrical stimulation, or (c) neurorrhaphy with the addition electrical stimulation and PEG. Functional recovery was assessed weekly for 16 weeks. At 16 weeks postoperatively, motoneuron survival, amount of regrowth, and specificity of regrowth were assessed by branch labeling and tissue analysis. Results The addition of brief intraoperative electrical stimulation improved all functional outcomes compared to suturing alone. The addition of PEG to electrical stimulation impaired this benefit. Motoneuron survival, amount of regrowth, and specificity of regrowth were unaltered at 16 weeks postoperative in all treatment groups. Conclusion The addition of brief intraoperative electrical stimulation to neurorrhaphy in this rodent model shows promising neurological benefit in the surgical repair of facial nerve injury. Level of Evidence Animal study.
  • Thumbnail Image
    Item
    Fast and slow rates of symptom progression in the transgenic SOD1 murine model of ALS
    (Office of the Vice Chancellor for Research, 2011-04-08) Haulcomb, Melissa M.; Mesnard, Nichole A.; Sanders, Virginia M.; Jones, Kathryn J.
    ALS is a disease targeting motoneurons (MN). In the SOD1 mouse model of ALS, an axonal dieback process is initiated during the pre-symptomatic stage where MN axons withdraw from target muscle. We have used facial nerve axotomy, which resembles the axonal die-back response, in pre-symptomatic SOD1 mice to investigate aspects of the disease. Apoptotic and pro-inflammatory gene expression is upregulated in pre-symptomatic SOD1 axotomized facial nuclei in addition to significant SOD1 MN death. Disease progression in symptomatic SOD1 facial nuclei resembles the molecular response initiated by axotomy. MN survival levels in symptomatic SOD1 and axotomized, presymptomatic SOD1 facial nuclei are similar. Therefore, facial nerve axotomy produces a disease onset-like response. The current study used behavioral testing to assess motor function, and revealed two groups of SOD1 mice with differing rates of symptomatic disease progression. The slow progression group had significantly less motor impairments compared to the fast progression group, but no difference in symptom onset was seen. Fast progression group showed higher mRNA levels for genes related to axonal injury. Symptomatic severity in SOD1 mice correlates to the cellular and molecular responses to axonal injury. Therefore, research using treatments to slow disease or extend.
  • Thumbnail Image
    Item
    Functional and Anatomical Outcomes of Facial Nerve Injury With Application of Polyethylene Glycol in a Rat Model
    (American Medical Association, 2019-01-01) Brown, Brandon L.; Asante, Tony; Welch, Haley R.; Sandelski, Morgan M.; Drejet, Sarah M.; Shah, Kishan; Runge, Elizabeth M.; Shipchandler, Taha Z.; Jones, Kathryn J.; Walker, Chandler L.; Anatomy and Cell Biology, IU School of Medicine
    Importance: Functional and anatomical outcomes after surgical repair of facial nerve injury may be improved with the addition of polyethylene glycol (PEG) to direct suture neurorrhaphy. The application of PEG has shown promise in treating spinal nerve injuries, but its efficacy has not been evaluated in treatment of cranial nerve injuries. Objective: To determine whether PEG in addition to neurorrhaphy can improve functional outcomes and synkinesis after facial nerve injury. Design, Setting, and Subjects: In this animal experiment, 36 rats underwent right facial nerve transection and neurorrhaphy with addition of PEG. Weekly behavioral scoring was done for 10 rats for 6 weeks and 14 rats for 16 weeks after the operations. In the 16-week study, the buccal branches were labeled and tissue analysis was performed. In the 6-week study, the mandibular and buccal branches were labeled and tissue analysis was performed. Histologic analysis was performed for 10 rats in a 1-week study to assess the association of PEG with axonal continuity and Wallerian degeneration. Six rats served as the uninjured control group. Data were collected from February 8, 2016, through July 10, 2017. Intervention: Polyethylene glycol applied to the facial nerve after neurorrhaphy. Main Outcomes and Measures: Functional recovery was assessed weekly for the 16- and 6-week studies, as well as motoneuron survival, amount of regrowth, specificity of regrowth, and aberrant branching. Short-term effects of PEG were assessed in the 1-week study. Results: Among the 40 male rats included in the study, PEG addition to neurorrhaphy showed no functional benefit in eye blink reflex (mean [SEM], 3.57 [0.88] weeks; 95% CI, -2.8 to 1.9 weeks; P = .70) or whisking function (mean [SEM], 4.00 [0.72] weeks; 95% CI, -3.6 to 2.4 weeks; P = .69) compared with suturing alone at 16 weeks. Motoneuron survival was not changed by PEG in the 16-week (mean, 132.1 motoneurons per tissue section; 95% CI, -21.0 to 8.4; P = .13) or 6-week (mean, 131.1 motoneurons per tissue section; 95% CI, -11.0 to 10.0; P = .06) studies. Compared with controls, neither surgical group showed differences in buccal branch regrowth at 16 (36.9 motoneurons per tissue section; 95% CI, -14.5 to 22.0; P = .28) or 6 (36.7 motoneurons per tissue section; 95% CI, -7.8 to 18.5; P = .48) weeks or in the mandibular branch at 6 weeks (25.2 motoneurons per tissue section; 95% CI, -14.5 to 15.5; P = .99). Addition of PEG had no advantage in regrowth specificity compared with suturing alone at 16 weeks (15.3% buccal branch motoneurons with misguided projections; 95% CI, -7.2% to 11.0%; P = .84). After 6 weeks, the number of motoneurons with misguided projections to the mandibular branch showed no advantage of PEG treatment compared with suturing alone (12.1% buccal branch motoneurons with misguided projections; 95% CI, -8.2% to 9.2%; P = .98). In the 1-week study, improved axonal continuity and muscular innervation were not observed in PEG-treated rats. Conclusions and Relevance: Although PEG has shown efficacy in treating other nervous system injuries, PEG in addition to neurorraphy was not beneficial in a rat model of facial nerve injury. The addition of PEG to suturing may not be warranted in the surgical repair of facial nerve injury. Level of Evidence: NA.
  • Thumbnail Image
    Item
    Identification of a resilient mouse facial motoneuron population following target disconnection by injury or disease
    (IOS, 2018) Setter, Deborah O.; Haulcomb, Melissa M.; Beahrs, Taylor; Meadows, Rena M.; Schartz, Nicole D.; Custer, Sara K.; Sanders, Virginia M.; Jones, Kathryn J.; Anatomy and Cell Biology, IU School of Medicine
    Background: When nerve transection is performed on adult rodents, a substantial population of neurons survives short-term disconnection from target, and the immune system supports this neuronal survival, however long-term survival remains unknown. Understanding the effects of permanent axotomy on cell body survival is important as target disconnection is the first pathological occurrence in fatal motoneuron diseases such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA). Objective: The goal of this study was to determine if facial motoneurons (FMN) could survive permanent target disconnection up to 26 weeks post-operation (wpo) after facial nerve axotomy (FNA). In addition, the potentially additive effects of immunodeficiency and motoneuron disease on post-axotomy FMN survival were examined. Methods: This study included three wild type (WT) mouse strains (C57BL/6J, B6SJL, and FVB/NJ) and three experimental models (RAG-2-/-: immunodeficiency; mSOD1: ALS; Smn-/-/SMN2+/+: SMA). All animals received a unilateral FNA, and FMN survival was quantified at early and extended post-operative timepoints. Results: In the C57BL/6J WT group, FMN survival significantly decreased at 10 wpo (55 ± 6%), and then remained stable out to 26 wpo (47 ± 6%). In the RAG-2-/- and mSOD1 groups, FMN death occurred much earlier at 4 wpo, and survival plateaued at approximately 50% at 10 wpo. The SMA model and other WT strains also exhibited approximately 50% FMN survival after FNA. Conclusion: These results indicate that immunodeficiency and motoneuron disease accelerate axotomy-induced neuron death, but do not increase total neuron death in the context of permanent target disconnection. This consistent finding of a target disconnection-resilient motoneuron population is prevalent in other peripheral nerve injury models and in neurodegenerative disease models as well. Characterization of the distinct populations of vulnerable and resilient motoneurons may reveal new therapeutic approaches for injury and disease.