Faculty Bibliography

Background/Purpose: Interferon (IFN)-alpha contributes to susceptibility and severe manifestations in systemic lupus erythematosus (SLE). The PRKG1 rs7897633 variant has been previously identified as the top hit in European ancestry patients with SLE and high IFN-alpha compared to those with low circulating IFN activity. However, the mechanisms by which PRKG1 polymorphisms impact the immune system remain unknown. PRKG1 codes for the cGMP-dependent protein kinase I (PKGI). Activation of PKGI leads to VASP phosphorylation, and the inhibition of RhoA and Rho-associated kinases (ROCK). A subgroup of patients with SLE exhibit higher ROCK activity in circulating immune cells compared to healthy controls. ROCK inhibition decreases IFN-alpha production and ameliorates disease in murine models of lupus. Accordingly, we aimed to assess whether the PRKG1 gene variant was associated with decreased gene expression and activity of PRKG1, hyperactivation of the ROCK pathway, and altered response to type I IFN.
Method(s): We used B lymphoblastoid cell lines (LCL) derived from healthy subjects of European ancestry (Coriell repositories) homozygous (AA or CC) and heterozygous (AC) at the rs7897633 SNP for all experiments. Gene expression of PRKG1, RHOA, and ROCK was assessed by RT-qPCR using gene-specific primers, normalized by GAPDH, and measured by the 2-DELTADELTACT method. IFN score at baseline and after treatment of LCL with increasing doses of IFN-alpha was measured by quantifying 3 canonical IFN-stimulated genes (IFIT1, MX1 and PKR) and summing to generate a score reflecting the degree of IFN-induced gene expression in the cells. Abundance of PKGI and VASP phosphorylation (as a surrogate of PKGI activity) were determined by Western blotting at baseline and after treatment with a PKGI agonist. ROCK2 enzymatic activity was performed by a colorimetric assay (Cell Biolabs). Unstimulated and stimulated cells were compared among PRKG1 genotype categories. Statistically significant differences were determined by Mann Whitney U test or sum-of-squares F test, as appropriate.
Result(s): PRKG1 expression was lower in the homozygous AA genotype as compared with the homozygous CC genotype in LCL (p< 0.05). In contrast, ROCK expression was higher in LCL with the AA rs7897633 genotype (p< 0.05). Compared to LCL with the homozygous AA variant of rs7897633, homozygous CC LCL have greater abundance of PKGI, phosphorylated VASP/total VASP ratio in response to a PKGI agonist (indicating increased PKGI activity), and lower baseline ROCK activity (sum-of-squares F test, p< 0.05). The IFN score was significantly higher in the homozygous CC allele LCL, both at baseline and with increasing doses of IFN-alpha, suggesting increased sensitivity to type I IFN (p< 0.05).
Conclusion(s): PRKG1 AA genotype associates with lower PRKG1 and higher ROCK mRNA expression, decreased PKGI abundance and activity, and greater ROCK baseline activity. In contrast, the rs7897633 CC genotype is associated with increased response to IFNalpha. Overall, these findings suggest an important role of genetic variation at PRKG1 in modulating the RhoA-ROCK pathway and regulating response to type I IFNs in LCL, which may have therapeutic implications in patients with SLE

INTRODUCTION:Huntington's disease is a neurodegenerative disease that is characterized by motor dysfunction, behavioral/psychiatric symptoms, and cognitive impairment. Because of the lack of availability of curative or disease modifying treatments, much of clinical practice in HD care to date has focused on symptomatic treatment. Recent work has created optimism surrounding possible emerging disease modifying therapeutics. HD is a developing therapeutic field with diverse and promising emerging therapies. AREAS COVERED:A PubMed literature review was completed to discover pertinent reviews and analyses. ClinicalTrials.gov was referenced to find updated information about ongoing and planned trials. Lastly, because of the rapidly evolving nature of HD treatments, drug manufacturer websites and press releases were reviewed to provide current information surrounding recently reported trial results. EXPERT OPINION:Recent setbacks involving antisense oligonucleotide research should not diminish enthusiasm and hope for the many other novel therapies currently being pursued. We remain optimistic about the many promising emerging therapies for HD, and we expect that growing knowledge about the pathophysiology of the underlying disease and constant advances in biotechnology will lead to therapies that have a meaningful impact in the lives of patients, their families, and those who care for them.

This is a summary report of clinical and regulatory issues discussed at the 2018 NINDS workshop, entitled "Accelerating Therapies for Antiepileptogenesis and Disease Modification". The intent of the workshop was to optimize and accelerate development of therapies for anti-epileptogenesis (AEG) and disease modification in the epilepsies. The working group discussed nomenclature for antiepileptogenic therapies, subdividing them into antiepileptogenic therapies" and "disease modifying therapies", both of which are urgently needed. We use the example of traumatic brain injury to explain issues and complexities in designing a trial for disease preventing antiepileptogenic therapies, including identifying timing of intervention, selecting the appropriate dose, and the need for biomarkers. We discuss the recent trials of vigabatrin to prevent onset and modify epilepsy outcome in children with tuberous sclerosis (Epistop and PreVeNT). We describe a potential approach to a disease modification trial in adults, using patients with Temporal Lobe Epilepsy. Finally, we discuss regulatory hurdles for antiepileptogenesis and disease modifying trials.

OBJECTIVE:This study was undertaken to examine long-term (up to 7.8 years) retention rate, safety, and tolerability of the antiseizure medication (ASM) cenobamate as adjunctive treatment in the open-label extension (OLE) of study YKP3089C013 (C013; ClinicalTrials.gov: NCT01397968). METHODS:Patients who completed the 12-week, multicenter, multinational, double-blind, randomized, placebo-controlled C013 study, which examined adjunctive cenobamate treatment of adults with uncontrolled focal seizures, were eligible to enroll in the OLE. During the OLE, dose adjustments of cenobamate and concomitant ASMs were allowed. Safety assessments included frequency of treatment-emergent adverse events (TEAEs) and serious TEAEs, TEAE severity, and TEAEs leading to discontinuation. Probability of patient continuation in the OLE was examined using a Kaplan-Meier analysis. RESULTS:One hundred forty-nine patients entered the OLE (median duration of cenobamate treatment = 6.25 years). As of the data cutoff, 57% of patients (85/149) remained in the OLE (median treatment duration = 6.8 years, range = 6.4-7.8 years). The median modal daily cenobamate dose was 200 mg (range = 50-400 mg). The probability of treatment continuation at 1-6 years of cenobamate treatment was 73%, 67%, 63%, 61%, 60%, and 59%, respectively. Among patients who continued at 1 year (n = 107), the probability of continuing at Years 2-5 was 92%, 87%, 83%, and 82%. The most common discontinuation reasons were patient withdrawal (19.5%, 29/149), adverse event (10.1%, 15/149), and lack of efficacy (5.4%, 8/149). TEAEs leading to discontinuation in 1% or more of patients were fatigue (1.3%, 2/149), ataxia (1.3%, 2/149), and memory impairment or amnesia (1.3%, 2/149). Dizziness (32.9%, 49/149), headache (26.8%, 40/149), and somnolence (21.5%, 32/149) were the most frequently reported TEAEs and were primarily mild or moderate in severity. SIGNIFICANCE/CONCLUSIONS:Long-term retention in the C013 OLE study demonstrated sustained safety and tolerability of adjunctive cenobamate treatment up to 7.8 years in adults with treatment-resistant focal seizures taking one to three ASMs.

OBJECTIVES/OBJECTIVE:To report a case of isolated third nerve palsy from pituitary apoplexy and perform a systematic literature review. MATERIALS AND METHODS/METHODS:MEDLINE/EMBASE databases were searched up to September 2020. INCLUSION CRITERIA/METHODS:Age≥18, isolated third nerve palsy from pituitary apoplexy. EXCLUSION CRITERIA/METHODS:Age<18, presence of other neurological findings, no hemorrhage or infarction of pituitary. RESULTS:Case report: A 76-year-old woman presented with headache and right-sided ptosis. Right-eye exam revealed complete ptosis, absent pupillary constriction and accommodation, depressed and abducted eye on primary gaze, and -1 impaired depression, adduction, elevation, without other neurological findings. Brain MRI was suggestive of pituitary apoplexy. Pathology after transsphenoidal resection revealed an infarcted pituitary adenoma. Third nerve palsy resolved completely in 21 days. Systematic review: Twenty-three studies reporting 35 patients were selected from 182 abstracts. Twenty-nine (83%) had complete isolated third nerve palsy. Headache was reported in 31 (97%). Thirty-one had hemorrhage and 1 had infarction of pituitary. Cavernous sinus invasion occurred in 14 (50%). Twenty-eight were managed surgically (80%) and 7 medically (20%). Nerve palsy resolved completely in 27 (82%) and partially in 4 (11%). CONCLUSIONS:Pituitary apoplexy is an important differential diagnosis in patients with isolated third nerve palsy. Isolated third nerve palsy in apoplexy appears to have favorable prognosis.

BACKGROUND:Infarction of the medulla has been associated with prolongation of the QTc, severe arrhythmia, and sudden cardiac death, yet the precise anatomical substrate remains uncertain. AIMS/OBJECTIVE:We sought to determine the possible anatomical structures relating to QTc-prolongation in patients with acute medullary infarction. METHODS:We included 12 subjects with acute ischemic medullary infarction on brain MRI, who presented within 4.5 h from the last known well time, with a 90-day follow-up. For an unbiased lesion analysis, medullary infarcts were manually outlined on diffusion weighted MRI and co-registered with an anatomical atlas. RESULTS:Nine out of 12 had QTc-prolongation. Qualitative and semi-quantitative comparisons were made between infarct location and QTc-prolongation. Among patients with QTc-prolongation, the greatest degree of congruence of the infarct location was over the dorsal vagal nucleus (DVN, 8 out of 9). There was a significant correlation between the number of sections showing infarction of the DVN and presence of QTc-prolongation (r = .582, p = .047). Among patients without QTc-prolongation, the maximum lesion overlap included the medial aspect of the gigantocelluar reticular nucleus of the reticular formation. CONCLUSION/CONCLUSIONS:We found that the DVN is a key anatomical substrate related to QTc-prolongation. Further studies with more patients and high-resolution, volumetric MRI are needed to confirm our findings.

BACKGROUND AND PURPOSE/OBJECTIVE:We reviewed the literature to evaluate cerebrospinal fluid (CSF) results from patients with coronavirus disease 2019 (COVID-19) who had neurological symptoms and had an MRI that showed (1) central nervous system (CNS) hyperintense lesions not attributed to ischemia and/or (2) leptomeningeal enhancement. We sought to determine if these findings were associated with a positive CSF severe acute respiratory syndrome associated coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR). METHODS:We performed a systematic review of Medline and Embase from December 1, 2019 to November 18, 2020. CSF results were evaluated based on the presence/absence of (1) ≥ 1 CNS hyperintense lesion and (2) leptomeningeal enhancement. RESULTS:In 117 publications, we identified 193 patients with COVID-19 who had an MRI of the CNS and CSF testing. There were 125 (65%) patients with CNS hyperintense lesions. Patients with CNS hyperintense lesions were significantly more likely to have a positive CSF SARS-CoV-2 PCR (10% [9/87] vs. 0% [0/43], p = 0.029). Of 75 patients who had a contrast MRI, there were 20 (27%) patients who had leptomeningeal enhancement. Patients with leptomeningeal enhancement were significantly more likely to have a positive CSF SARS-CoV-2 PCR (25% [4/16] vs. 5% [2/42], p = 0.024). CONCLUSION/CONCLUSIONS:The presence of CNS hyperintense lesions or leptomeningeal enhancement on neuroimaging from patients with COVID-19 is associated with increased likelihood of a positive CSF SARS-CoV-2 PCR. However, a positive CSF SARS-CoV-2 PCR is uncommon in patients with these neuroimaging findings, suggesting they are often related to other etiologies, such as inflammation, hypoxia, or ischemia.

OBJECTIVE:Need for rescue therapy differs among patients with seizure clusters. Diazepam nasal spray is approved to treat seizure clusters in patients with epilepsy ≥6 years of age. This analysis used interim data from a phase 3 safety study to assess safety profile and effectiveness of diazepam nasal spray using average number of doses/month as a proxy measurement. METHODS:This phase 3, open-label, repeat-dose, safety study of diazepam nasal spray enrolled patients (6-65 years) with epilepsy and need of benzodiazepine rescue. Patients were stratified by average number of doses/month (<2, moderate frequency; 2-5, high frequency; >5, very-high frequency). Safety was evaluated based on treatment-emergent adverse events (TEAEs), assessed nasal irritation, and olfaction. The proportion of treatments given as a second dose was used as an exploratory proxy for effectiveness. RESULTS:Of 175 enrolled patients (data cutoff, October 31, 2019), 158 received ≥1 dose of diazepam nasal spray. Frequency of use was moderate in 43.7% of patients, high in 50.6% of patients, and very high in 5.7% of patients. Patients treated 3397 seizure episodes (moderate frequency, 14.2%; high frequency, 59.9%; very high frequency, 25.8%). Nasal discomfort was the most common treatment-related TEAE in all groups. No notable changes in nasal irritation or olfaction were observed. Second doses represented only 2.5%, 7.5%, and 17.2% of all doses in the moderate-, high-, and very-high-frequency groups, respectively. Overall retention rate was 82.9%, without an observed relationship to frequency of use. SIGNIFICANCE/CONCLUSIONS:Frequency of dosing diazepam nasal spray had little impact on the safety/tolerability profile across a range of <2 to >5 doses/month. Effectiveness was suggested for all dosing frequencies by the high proportion of seizure clusters not treated with a second dose. These results support the utility, safety profile, and effectiveness of diazepam nasal spray across frequencies of seizure cluster burden.

OBJECTIVE:Lennox-Gastaut syndrome (LGS) is an epileptic encephalopathy that is often treatment resistant. Efficacy and safety of add-on cannabidiol (CBD) to treat seizures associated with LGS was demonstrated in two randomized controlled trials (RCTs). Patients who completed the RCTs were invited to enroll in this long-term open-label extension (OLE) trial, GWPCARE5 (NCT02224573). We present the final analysis of safety and efficacy outcomes from GWPCARE5. METHODS:Patients received plant-derived highly purified CBD (Epidiolex in the United States; Epidyolex in the European Union; 100 mg/ml oral solution), titrated to a target maintenance dose of 20 mg/kg/day over 2 weeks. Based on response and tolerability, CBD could then be reduced or increased up to 30 mg/kg/day. RESULTS:Of 368 patients with LGS who completed the RCTs, 366 (99.5%) enrolled in this OLE. Median and mean treatment duration were 1090 and 826 days (range = 3-1421), respectively, with a mean modal dose of 24 mg/kg/day. Adverse events (AEs) occurred in 96% of patients, serious AEs in 42%, and AE-related discontinuations in 12%. Common AEs were convulsion (39%), diarrhea (38%), pyrexia (34%), and somnolence (29%). Fifty-five (15%) patients experienced liver transaminase elevations more than three times the upper limit of normal; 40 (73%) were taking concomitant valproic acid. Median percent reductions from baseline ranged 48%-71% for drop seizures and 48%-68% for total seizures through 156 weeks. Across all 12-week visit windows, 87% or more of patients/caregivers reported improvement in the patient's overall condition on the Subject/Caregiver Global Impression of Change scale. SIGNIFICANCE/CONCLUSIONS:Long-term add-on CBD treatment had a similar safety profile as in the original RCTs. Sustained reductions in drop and total seizure frequency were observed for up to 156 weeks, demonstrating long-term benefits of CBD treatment for patients with LGS.

An increasing number of identified Parkinson's disease (PD) risk loci contain genes highly expressed in innate immune cells, yet their role in pathology is not understood. We hypothesize that PD susceptibility genes modulate disease risk by influencing gene expression within immune cells. To address this, we have generated transcriptomic profiles of monocytes from 230 individuals with sporadic PD and healthy subjects. We observed a dysregulation of mitochondrial and proteasomal pathways. We also generated transcriptomic profiles of primary microglia from brains of 55 subjects and observed discordant transcriptomic signatures of mitochondrial genes in PD monocytes and microglia. We further identified 17 PD susceptibility genes whose expression, relative to each risk allele, is altered in monocytes. These findings reveal widespread transcriptomic alterations in PD monocytes, with some being distinct from microglia, and facilitate efforts to understand the roles of myeloid cells in PD as well as the development of biomarkers.