Selective Upregulation of SIRT1 Expression in Retinal Ganglion Cells by AAV-Mediated Gene Delivery Increases Neuronal Cell Survival and Alleviates Axon Demyelination Associated with Optic Neuritis.

Optic neuritis (ON), the most common ocular manifestation of multiple sclerosis, is an autoimmune inflammatory demyelinating disease also characterized by degeneration of retinal ganglion cells (RGCs) and their axons, which commonly leads to visual impairment despite attempted treatments. Although ON disease etiology is not known, changes in the redox system and exacerbated optic nerve inflammation play a major role in the pathogenesis of the disease. Silent information regulator 1 (sirtuin-1/SIRT1) is a ubiquitously expressed NAD+-dependent deacetylase, which functions to reduce/prevent both oxidative stress and inflammation in various tissues. Non-specific upregulation of SIRT1 by pharmacologic and genetic approaches attenuates RGC loss in experimental ON. Herein, we hypothesized that targeted expression of SIRT1 selectively in RGCs using an adeno-associated virus (AAV) vector as a delivery vehicle is an effective approach to reducing neurodegeneration and preserving vision in ON. We tested this hypothesis through intravitreal injection of AAV7m8.SNCG.SIRT1, an AAV2-derived vector optimized for highly efficient SIRT1 transgene transfer and protein expression into RGCs in mice with experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis that recapitulates optic neuritis RGC loss and axon demyelination. Our data show that EAE mice injected with a control vehicle exhibit progressive alteration of visual function reflected by decreasing optokinetic response (OKR) scores, whereas comparatively, AAV7m8.SNCG.SIRT1-injected EAE mice maintain higher OKR scores, suggesting that SIRT1 reduces the visual deficit imparted by EAE. Consistent with this, RGC survival determined by immunolabeling is increased and axon demyelination is decreased in the AAV7m8.SNCG.SIRT1 RGC-injected group of EAE mice compared to the mouse EAE counterpart injected with a vehicle or with control vector AAV7m8.SNCG.eGFP. However, immune cell infiltration of the optic nerve is not significantly different among all EAE groups of mice injected with either vehicle or AAV7m8.SNCG.SIRT1. We conclude that despite minimally affecting the inflammatory response in the optic nerve, AAV7m8-mediated SIRT1 transfer into RGCs has a neuroprotective potential against RGC loss, axon demyelination and vison deficits associated with EAE. Together, these data suggest that SIRT1 exerts direct effects on RGC survival and function.

Emerging concepts in the treatment of optic neuritis: mesenchymal stem cell-derived extracellular vesicles.

BACKGROUND: Optic neuritis (ON) is frequently encountered in multiple sclerosis, neuromyelitis optica spectrum disorder, anti-myelin oligodendrocyte glycoprotein associated disease, and other systemic autoimmune disorders. The hallmarks are an abnormal optic nerve and inflammatory demyelination; episodes of optic neuritis tend to be recurrent, and particularly for neuromyelitis optica spectrum disorder, may result in permanent vision loss. MAIN BODY: Mesenchymal stem cell (MSC) therapy is a promising approach that results in remyelination, neuroprotection of axons, and has demonstrated success in clinical studies in other neuro-degenerative diseases and in animal models of ON. However, cell transplantation has significant disadvantages and complications. Cell-free approaches utilizing extracellular vesicles (EVs) produced by MSCs exhibit anti-inflammatory and neuroprotective effects in multiple animal models of neuro-degenerative diseases and in rodent models of multiple sclerosis (MS). EVs have potential to be an effective cell-free therapy in optic neuritis because of their anti-inflammatory and remyelination stimulating properties, ability to cross the blood brain barrier, and ability to be safely administered without immunosuppression. CONCLUSION: We review the potential application of MSC EVs as an emerging treatment strategy for optic neuritis by reviewing studies in multiple sclerosis and related disorders, and in neurodegeneration, and discuss the challenges and potential rewards of clinical translation of EVs including cell targeting, carrying of therapeutic microRNAs, and prolonging delivery for treatment of optic neuritis.

Para-neoplastic optic neuritis presenting in a child with fusion positive localised para-testicular alveolar rhabdomyosarcoma.

We present the case of a 13 year old boy, with sudden onset painful unilateral visual loss, prior to commencing chemotherapy for alveolar rhabdomyosarcoma. Cases of para-neoplastic optic neuritis have been reported in adult cancer patients, however there are no published reports of this phenomenon occurring in children. Our patient had full recovery of his vision, following 6 weeks treatment with steroids, immunoglobulins and standard chemotherapy as per high risk arm of European pediatric soft tissue sarcoma group (EpSSG) Rhabdomyosarcoma (RMS) 2005 guidelines. Our case highlights that para-neoplastic optic neuritis can occur in children. In pediatric patients presenting with optic neuritis and normal auto-antibody screen, an occult or underlying tumor should be considered.

Current Recommendations on Optic Neuritis. / Aktuelle Empfehlungen zur Optikusneuritis.

BACKGROUND: Optic neuritis is a special challenge to the ophthalmologist. It is a relatively frequent condition but difficult to seize morphologically. It has neurological implications and is subject matter of recent trials. METHODS: Selective literature search including the authors' professional experience. RESULTS: Practical aids for the ophthalmological management of optic neuritis are derived from the best available evidence and the recent literature is discussed. CONCLUSIONS: The present paper provides evidence-based recommendations for a safe handling of optic neuritis as well as information on current issues.

Refractory optic perineuritis related to granulomatosis with polyangiitis treated with intensive immunosuppressive therapy combined with plasma exchange.

Optic perineuritis (OPN), which is an inflammatory disorder affecting the optic nerve sheath, is one of the rare complications in granulomatosis with polyangiitis (GPA). Although several groups have reported that immunosuppressive therapies are generally effective against GPA-associated OPN, so far, there is little information as to other options for refractory cases. Here we demonstrate a case of GPA-associated OPN, which is refractory to potent immunosuppressive therapy including high-dose glucocorticoid, intravenous cyclophosphamide and rituximab therapy, and effective application of therapeutic plasma exchange. We also report here that CSF IL-6 levels may serve as a new biomarker for GPA-associated OPN.

Optic neuritis induced by 5-fluorouracil chemotherapy: Case report and review of the literature.

Introduction: For over 50 years, 5-Fluorouracil has played a critical role in the treatment of numerous malignancies, including colorectal cancer. Ocular side effects are uncommon and include blurred vision, conjunctivitis, excessive lacrimation and keratitis. Case report: We report a 57-year-old male with metastatic colorectal cancer who had received extensive chemotherapy with 5-Fluorouracil-based regimens for over 12 months. Following his seventh cycle of cetuximab/FOLFIRI, he developed acute onset global headache, nausea and loss of vision in the right eye. After detailed investigations, including ophthalmologic and neurologic consultations, a diagnosis of optic neuritis was made. Management and outcome: Chemotherapy was ceased immediately, and intravenous methylprednisolone (1 g) daily for five days was commenced. His headache resolved and vision started to improve within 24 h. Three weeks after completion of corticosteroids, constriction of the right visual field had fully resolved. Discussion: Atypical optic neuritis is an inflammatory optic neuropathy that can be caused by ischaemia, mechanical compression, nutritional deficiency, toxins and drugs. Drug-induced optic neuritis, while rare, is associated with cytotoxic medications including methotrexate, cisplatin, carboplatin, vincristine and paclitaxel. There have only been five previous case reports implicating 5-Fluorouracil in the development of optic neuropathy. The likelihood of the adverse drug reaction due to 5-Fluorouracil was assessed using the Naranjo algorithm. A score of +7 indicates probable causality. Clinicians should be alert to this potential ocular toxicity in order to initiate prompt cessation of treatment and early ophthalmology referral to prevent visual loss and damage to ocular structures.

Prognostic indicators of improvement with therapeutic plasma exchange in pediatric demyelination.

OBJECTIVES: To determine the safety and clinical benefit of therapeutic plasma exchange (TPE) as rescue therapy in children with acute inflammatory demyelinating CNS syndromes and to identify baseline prognostic indicators of treatment improvement. METHODS: This single-center retrospective pediatric cohort included all consecutive patients admitted to our hospital over the period from 2003 to 2017 because of a steroid-refractory acute CNS event presumed to be inflammatory who required TPE. Functional status assessment to identify improvement included the following performance category scales: visual outcome, bladder control, gait, and Expanded Disability Status Scale (EDSS). These assessments were performed before and after TPE in every patient. RESULTS: Sixty-five children requiring TPE to treat 78 CNS attacks were included for analysis. Median age at TPE was 10.5 years (1.9-18 years); 45% were girls. Seropositivity (aquaporin-4 water channel-immunoglobulin G [IgG] or myelin oligodendrocyte glycoprotein-IgG) was found in 20 of 42 (48%) patients. Attack phenotypes leading to TPE were optic neuritis (ON) in 42%, longitudinally extensive transverse myelitis (LETM) in 31%, ON + LETM in 15%, and other combined syndromes in 11%. Overall, moderate to marked neurologic improvement was observed in 72% of children at the end of TPE and in 88.5% at 6 months of follow-up. Lower baseline scores on the EDSS, visual outcome, and gait scales were found to be independent prognostic indicators of treatment benefit. Sex, age at onset and at TPE, attack phenotype, disease duration, and time from attack onset to TPE initiation were not significantly associated with treatment outcome. Adverse events were observed in 31 of 524 (5.9%) procedures, being severe in 4. CONCLUSIONS: TPE was an effective rescue therapy associated with functional improvement. No therapeutic window for TPE initiation was identified in this pediatric cohort. Overall frequency of adverse events was low; however, serious events should be anticipated and avoided. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for children with acute inflammatory demyelinating CNS syndromes, TPE leads to functional improvement.

Optic Neuritis.

PURPOSE OF REVIEW: This article discusses the clinical presentation, evaluation, and management of the patient with optic neuritis. Initial emphasis is placed on clinical history, examination, diagnostic testing, and medical decision making, while subsequent focus is placed on examining specific inflammatory optic neuropathies. Clinical clues, examination findings, neuroimaging, and laboratory testing that differentiate autoimmune, granulomatous, demyelinating, infectious, and paraneoplastic causes of optic neuritis are assessed, and current treatments are evaluated. RECENT FINDINGS: Advances in technology and immunology have enhanced our understanding of the pathologies driving inflammatory optic nerve injury. Clinicians are now able to interrogate optic nerve structure and function during inflammatory injury, rapidly identify disease-relevant autoimmune targets, and deliver timely therapeutics to improve visual outcomes. SUMMARY: Optic neuritis is a common clinical manifestation of central nervous system inflammation. Depending on the etiology, visual prognosis and the risk for recurrent injury may vary. Rapid and accurate diagnosis of optic neuritis may be critical for limiting vision loss, future neurologic disability, and organ damage. This article will aid neurologists in formulating a systematic approach to patients with optic neuritis.

Higher health care use before a clinically isolated syndrome with or without subsequent MS.

BACKGROUND: To establish whether a unique multiple sclerosis (MS) prodrome exists by comparing health care utilization in the five-year period before initial presentation with optic neuritis (ON) or transverse myelitis (TM) among those who were and were not subsequently diagnosed with MS. METHODS: Using population-based administrative health data we conducted a retrospective cohort study in three Canadian provinces. We identified individuals with a clinically isolated syndrome (ON or TM), who were eventually diagnosed with MS (CIS-MS) or not (CIS-non MS), and a control cohort matched on age, sex and region without a CIS. We compared rates of hospitalization, physician services use and prescription drug use in the five years before the first ON or TM claim (labeled years -1,-2,-3,-4,-5) using negative binomial regression models adjusted for age, sex, socioeconomic status and index year. RESULTS: We identified 1,155 CIS-MS cases, 20,638 CIS-non MS cases, and 108,726 matched controls. Compared to matched controls, the CIS-MS cohort had a higher hospitalization rate (years -5 and -1), physician visits (all years) and prescription drug use (years -4 and -1). Compared to matched controls, the CIS-non MS cohort had a higher rate of hospitalizations (all years), physician visits (all years) and prescription drug use (all years). CONCLUSION: Health care use was higher in individuals with a CIS than without a CIS in the five years before an incident demyelinating event, regardless of whether they were subsequently diagnosed with MS. This suggests that there is a prodromal period before CIS which is not unique to MS.

Empowering Mesenchymal Stem Cells for Ocular Degenerative Disorders.

Multipotent mesenchymal stem cells (MSCs) have been employed in numerous pre-clinical and clinical settings for various diseases. MSCs have been used in treating degenerative disorders pertaining to the eye, for example, age-related macular degeneration, glaucoma, retinitis pigmentosa, diabetic retinopathy, and optic neuritis. Despite the known therapeutic role and mechanisms of MSCs, low cell precision towards the targeted area and cell survivability at tissue needing repair often resulted in a disparity in therapeutic outcomes. In this review, we will discuss the current and feasible strategy options to enhance treatment outcomes with MSC therapy. We will review the application of various types of biomaterials and advances in nanotechnology, which have been employed on MSCs to augment cellular function and differentiation for improving treatment of visual functions. In addition, several modes of gene delivery into MSCs and the types of associated therapeutic genes that are important for modulation of ocular tissue function and repair will be highlighted.

RECURRENT ATYPICAL OPTIC NEURITIS AS THE LEADING SIGN OF FABRY DISEASE.

Acute optic neuritis has the age and sex adjusted incidence of 1-5/100,000 in general population. It is mostly a disorder affecting young Caucasian women (31-32 years). Patients present to a wide range of clinicians including general practitioner, emergency physician, ophthalmologist, neurologist, etc. There are two main clinical presentations of optic neuritis, typical and atypical. It is of great importance to distinguish these two types of optic neuritis in order to detect the underlying etiology and plan appropriate and timely treatment. We present a young female patient (36 years) admitted to Department of Ophthalmology due to visual loss on the left eye. Magnetic resonance imaging showed demyelinating lesions in frontal and parietal lobe, periventricularly, in mesencephalon and right cerebellar hemisphere, and left optic neuritis; magnetic resonance angiography was normal. The patient's history revealed renal dysfunction, hypothyroidism, and miscarriage in the 6th month of pregnancy due to eclampsia, and Fabry disease in family (mother and two sisters). She was transferred to the Department of Neurology for further evaluation of the demyelinating disorder of the central nervous system. The patient received corticosteroid therapy (methylprednisolone 1 g) for 5 days with regression of visual disturbances on the left eye. After this acute treatment, the question of definitive diagnosis remained, along with further treatment of the underlying cause. Considering renal dysfunction, miscarriage, arterial hypertension, positive genetic and biochemical testing for Fabry disease in close relatives (mother), we suspected that she also had Fabry disease. She was tested and the results were positive. We concluded that optic neuritis was the first sign of Fabry disease in this case, reflecting acute atypical neuroinflammatory disease.

SIRT1 and NRF2 Gene Transfer Mediate Distinct Neuroprotective Effects Upon Retinal Ganglion Cell Survival and Function in Experimental Optic Neuritis.

Purpose: Optic neuritis is a condition defined by autoimmune-mediated demyelination of the optic nerve and death of retinal ganglion cells. SIRT1 and NRF2 stimulate anti-inflammatory mechanisms and have previously demonstrated therapeutic value in preclinical models of neurodegenerative disease. Here we investigated the neuroprotective potential of SIRT1 or NRF2 gene transfer using adeno-associated virus (AAV) vectors in the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis. Methods: C57Bl/6J mice were administered intravitreal doses of AAV2 vectors and immunized to induce EAE symptoms. Visual function was examined by recording the optokinetic response (OKR) just prior to EAE induction and once every 7 days postinduction for 7 weeks. Retina and optic nerves were harvested to investigate retinal ganglion cell survival (immunolabeling with Brn3a antibodies); inflammation (hematoxylin and eosin staining); and demyelination (luxol fast blue staining). Results: Animals modeling EAE demonstrate reduced visual acuity compared to sham-induced controls. Intravitreal delivery of AAV2-NRF2 did not preserve visual function. However, AAV2-SIRT1 mediated significant preservation of the OKR compared to AAV2-eGFP controls. Treatment with AAV2-NRF2 promoted RGC survival while AAV2-SIRT1 mediated an upward trend in protection compared to vehicle and AAV2-eGFP controls. Neither NRF2 nor SIRT1 gene augmentation was able to suppress optic nerve inflammation or demyelination. Conclusions: AAV-mediated overexpression of NRF2 or SIRT1 within RGCs mediates distinct neuroprotective effects upon visual function and RGC survival. This study expands our understanding of SIRT1 and NRF2-mediated neuroprotection in the context of MS pathogenesis and optic neuropathies.

Neuropatia óptica tóxica por inalação de metanol / Optic neuropathy toxic after methanol inhalation

Resumo A intoxicação por metanol é um evento considerado raro, principalmente quando feita por via inalatória. Retratou-se neste presente estudo um relato de caso de um paciente que desenvolveu neurite óptica tóxica após exposição ao metanol e ácido acético por via inalatória em seu ambiente de trabalho. Foi descrito sobre as terapias obtidas na literatura, bem como as manifestações clínicas e o manejo a este paciente.

Abstract The methanol toxicity is considered rare event , especially when taken by inhalation . It was portrayed in the present study a case report of a patient who developed toxic optic neuritis after exposure to methanol and acetic acid by inhalation in the workplace . It was described for the therapies from the literature as well as the clinical manifestations and management in this patient.

Clinical course, therapeutic responses and outcomes in relapsing MOG antibody-associated demyelination.

OBJECTIVE: We characterised the clinical course, treatment and outcomes in 59 patients with relapsing myelin oligodendrocyte glycoprotein (MOG) antibody-associated demyelination. METHODS: We evaluated clinical phenotypes, annualised relapse rates (ARR) prior and on immunotherapy and Expanded Disability Status Scale (EDSS), in 218 demyelinating episodes from 33 paediatric and 26 adult patients. RESULTS: The most common initial presentation in the cohort was optic neuritis (ON) in 54% (bilateral (BON) 32%, unilateral (UON) 22%), followed by acute disseminated encephalomyelitis (ADEM) (20%), which occurred exclusively in children. ON was the dominant phenotype (UON 35%, BON 19%) of all clinical episodes. 109/226 (48%) MRIs had no brain lesions. Patients were steroid responsive, but 70% of episodes treated with oral prednisone relapsed, particularly at doses <10 mg daily or within 2 months of cessation. Immunotherapy, including maintenance prednisone (P=0.0004), intravenous immunoglobulin, rituximab and mycophenolate, all reduced median ARRs on-treatment. Treatment failure rates were lower in patients on maintenance steroids (5%) compared with non-steroidal maintenance immunotherapy (38%) (P=0.016). 58% of patients experienced residual disability (average follow-up 61 months, visual loss in 24%). Patients with ON were less likely to have sustained disability defined by a final EDSS of ≥2 (OR 0.15, P=0.032), while those who had any myelitis were more likely to have sustained residual deficits (OR 3.56, P=0.077). CONCLUSION: Relapsing MOG antibody-associated demyelination is strongly associated with ON across all age groups and ADEM in children. Patients are highly responsive to steroids, but vulnerable to relapse on steroid reduction and cessation.

Neurosarcoidosis: unusual presentations and considerations for diagnosis and management.

BACKGROUND: Sarcoidosis is a chronic, multisystem disease characterised by non-necrotising granulomatous inflammation of unknown aetiology. Most commonly, the lungs, lymph nodes, skin and eyes are affected in sarcoidosis; however, nervous system involvement occurs in approximately 5%-15% of cases. Any part of the nervous system can be affected by sarcoidosis. CASES: Herein we describe three unusual patient presentations of neurosarcoidosis, one with optic neuritis, a second with hydrocephalus and a third with cervical myelopathy. CONCLUSIONS: We include pertinent details about their presentations, imaging findings, pathology, management and clinical course.

Neuromyelitis optica spectrum disorder (NMOSD): A new concept.

The relationship between neuromyelitis optica (NMO) and multiple sclerosis (MS) has long been controversial. NMO was previously considered a form of MS involving predominantly the spinal cord and optic nerve. However, since the discovery of NMO-IgG/aquaporin-4 (AQP4) antibody, an NMO-specific autoantibody to AQP4, some unique clinical features, and magnetic resonance imaging (MRI) and other laboratory findings in NMO, have been further clarified. AQP4 antibody is now the most important laboratory finding for the diagnosis of NMO. Besides typical NMO, some patients with recurrent optic neuritis or recurrent longitudinally extensive transverse myelitis alone are also often positive for AQP4 antibody. Moreover, studies of AQP4 antibody-positive patients have revealed that brain and brainstem lesions are not uncommon in NMO, and some patterns appear to be unique to NMO. All these findings have expanded the NMO concept into 'NMO spectrum disorder' (NMOSD), and new criteria have recently been published. A new antigenic target, myelin oligodendrocyte glycoprotein (MOG), has also been discovered recently. This new antibody seems to correspond to around 20% of seronegative patients, but its specificity needs to be evaluated more precisely, especially in pediatric populations. These recent findings may also have therapeutic impact, as it has been demonstrated that many MS drugs can exacerbate NMO. This report provides an overview of the clinical and neuroimaging features of NMOSD, followed by its treatment.

[Current recommendations on optic neuritis]. / Aktuelle Empfehlungen zur Neuritis nervi optici.

BACKGROUND: The diagnostics and therapy of optic neuritis are complex and require interdisciplinary cooperation. AIM: Compact, up-to-date recommendations for the clinician appear to be desirable. MATERIAL AND METHODS: A selective literature search including the authors' professional experience was carried out. An algorithm for the practical approach to optic neuritis was derived from the best available evidence. RESULTS: Our recommendation distinguishes between compulsory and optional investigations. Differential diagnostic cues with regard to atypical optic neuritis and other optic neuropathies are shown. Standard therapy patterns and means of escalation are suggested. Indications for referral are presented. CONCLUSION: The algorithm suggested in this article provides ophthalmologists with an effective orientation aid for the complete treatment procedure of optic neuritis.

[New aspects in the therapy of multiple sclerosis and optic neuritis]. / Neue Aspekte in der Therapie der multiplen Sklerose und Optikusneuritis.

BACKGROUND: Despite the success of recently introduced immunomodulatory therapies, multiple sclerosis and its ophthalmic manifestation as optic neuritis lead to irreversible axonal degeneration. Hence, it would be desirable to apply a neuroprotective therapy in parallel. RESULTS AND DISCUSSION: We identified erythropoietin as an available and approved drug exerting neuroprotective effects in addition to its hematopoetic action. After several successful preclinical experiments, the pilot trial VISION PROTECT has shown that 33,000 IU erythropoietin, given intravenously on 3 consecutive days, preserves the retinal nerve fibre layer to a significant extent. This therapy will now be evaluated in a full scale and adequately powered trial to challenge this hypothesis. The TONE trial (Treatment of Optic Neuritis with Erythropoietin, NCT01962571) is a multicentric, prospective, double-blinded, clinical trial evaluating the same therapeutic regimen primarily with regard to thickness of the retinal nerve fibre layer and low contrast visual acuity.

Neuro-ophthalmologic manifestations of systemic lupus erythematosus: a systematic review.

Herein we summarize the clinical presentation, treatment and outcome of neuro-ophthalmologic manifestations in patients with systemic lupus erythematosus (SLE). We performed a systematic review of the neuro-ophthalmologic manifestations of SLE reported in the English literature from 1970 to 2010 by a Medline search. The prevalence of neuro-ophthalmologic manifestations is 3.6% in adult and 1.6% in childhood SLE patients. Neuro-ophthalmologic manifestations of SLE are highly variable, with the commonest presentation being optic neuritis, followed by myasthenia gravis, visual field defects and pseudotumor cerebri. The underlying pathology was thought to be either SLE activity or its vascular complications. Most neuro-ophthalmologic manifestations of SLE are responsive to high-dose glucocorticoids. Anticoagulation is indicated when there is concomitant antiphospholipid syndrome. SLE-related neuromyelitis optica is often refractory to treatment and 92% of patients require multiple immunosuppressive protocols. Neuro-ophthalmologic manifestations of SLE are uncommon but heterogeneous. The prognosis of neuro-ophthalmologic manifestations in SLE is generally good because of their rapid response to glucocorticoids. Relapses of these manifestations may be reduced by the use of maintenance immunosuppression. Cyclophosphamide, azathioprine, plasmapheresis, intravenous immunoglobulin and rituximab can be considered in glucocorticoid-dependent or refractory cases. Anticoagulation is indicated when there is concomitant antiphospholipid syndrome.