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Lysosomal function is impaired in Niemann-Pick disease type C1 (NPC1), a rare and inherited neurodegenerative disorder, resulting in late endosomal/lysosomal accumulation of unesterified cholesterol. The precise pathogenic mechanism of NPC1 remains incompletely understood. In this study, we employed metabolomics to uncover secondary accumulated substances in NPC1. Our findings unveiled a substantial elevation in the levels of three alkyl-lysophosphatidylcholine [alkyl-LPC, also known as lyso-platelet activating factor (PAF)] species in NPC1 compared to controls across various tissues, including brain tissue from individuals with NPC1, liver, spleen, cerebrum, cerebellum, and brain stem from NPC1 mice, as well as in both brain and liver tissue from NPC1 cats. The three elevated alkyl-LPC species were as follows: LPC O-16:0, LPC O-18:1, and LPC O-18:0. However, the levels of PAF 16:0, PAF 18:1, and PAF 18:0 were not altered in NPC1. In the NPC1 feline model, the brain and liver alkyl-LPC levels were reduced following 2-hydroxypropyl-β-cyclodextrin (HPβCD) treatment, suggesting that alkyl-LPCs are secondary storage metabolites in NPC1 disease. Unexpectedly, cerebrospinal fluid (CSF) levels of LPC O-16:0 and LPC O-18:1 were decreased in individuals with NPC1 compared to age-appropriate comparison samples, and their levels were increased in 80% of participants 2 years after intrathecal HPβCD treatment. The fold increases in CSF LPC O-16:0 and LPC O-18:1 levels were more pronounced in responders compared to nonresponders. This study identified alkyl-LPC species as secondary storage metabolites in NPC1 and indicates that LPC O-16:0 and LPC O-18:1, in particular, could serve as potential biomarkers for tracking treatment response in NPC1 patients., Competing Interests: Conflict of interest Xuntian Jiang is an Editorial Board Member of Journal of Lipid Research. The other author declares that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: Extracellular signal-regulated kinase (ERK1/2) is a conserved central intracellular signaling cascade involved in many aspects of neuronal development and plasticity. Converging evidence support investigation of ERK1/2 activity in autism spectrum disorder (ASD). We previously reported enhanced baseline lymphocytic ERK1/2 activation in autism, and now we extend our work to investigate the early phase kinetics of lymphocytic ERK1/2 activation in idiopathic ASD., Method: Study participants included 67 individuals with ASD (3-25 years of age), 65 age- and sex-matched typical developing control (TDC) subjects, and 36 age-, sex-, and IQ-matched developmental disability control (DDC) subjects matched to those with ASD and IQ <90. We completed an additional analysis comparing results from ASD, TDC, and DDC groups with data from 37 individuals with Fragile X syndrome (FXS). All subjects had blood lymphocyte samples analyzed by flow cytometry following stimulation with phorbol ester and sequentially analyzed for ERK1/2 activation (phosphorylation) at several time points., Results: The ASD group (mean = 5.81 minutes; SD = 1.5) had a significantly lower (more rapid) mean ERK1/2 T 1/2 activation value than both the DDC group (mean = 6.78 minutes; SD = 1.6; p = .00078) and the TDC group (mean = 6.4 minutes; SD = 1.5; p = .025). More rapid ERK1/2 T 1/2 activation times did correlate with increased social impairment across all study groups including the ASD cohort. Differences in ERK1/2 T 1/2 activation were more pronounced in younger than in older individuals in the primary analysis. The ASD group additionally had more rapid activation times than the FXS group, and the FXS group activation kinetics did not differ from those of the TDC and DDC groups., Conclusion: Our findings indicate that lymphocytic ERK1/2 activation kinetics are dysregulated in persons with ASD, marked by more rapid early phase activation. Group differences in ERK1/2 activation kinetics appear to be driven by findings from the youngest children analyzed., Diversity & Inclusion Statement: We worked to ensure sex and gender balance in the recruitment of human participants. We actively worked to promote sex and gender balance in our author group. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work., (Copyright © 2023. Published by Elsevier Inc.)

Purpose: Niemann-Pick disease type C1 (NPC1) is a neurodegenerative lysosomal disorder caused by pathogenic variants in NPC1. Disease progression is monitored using the NPC Neurological Severity Scale, but there are currently no established validated or qualified biomarkers. Neurofilament light chain (NfL) is being investigated as a biomarker in multiple neurodegenerative diseases., Methods: Cross-sectional and longitudinal cerebrospinal fluid (CSF) samples were obtained from 116 individuals with NPC1. NfL levels were measured using a solid-phase sandwich enzyme-linked immunosorbent assay and compared with age-appropriate non-NPC1 comparison samples., Results: Median levels of NfL were elevated at baseline (1152 [680-1840] pg/mL) in NPC1 compared with controls (167 [82-372] pg/mL; P < .001). Elevated NfL levels were associated with more severe disease as assessed by both the 17-domain and 5-domain NPC Neurological Severity Score. Associations were also observed with ambulation, fine motor, speech, and swallowing scores. Although treatment with the investigational drug 2-hydroxypropyl-β-cyclodextrin (adrabetadex) did not decrease CSF NfL levels, miglustat therapy over time was associated with a decrease (odds ratio = 0.77, 95% CI = 0.62-0.96)., Conclusion: CSF NfL levels are increased in individuals with NPC1, associated with clinical disease severity, and decreased with miglustat therapy. These data suggest that NfL is a biomarker that may have utility in future therapeutic trials., Competing Interests: Conflict of Interest The authors declare no conflicts of interest., (Published by Elsevier Inc.)

Niemann-Pick disease type C1 (NPC1) is a fatal, neurodegenerative, cholesterol storage disorder. With new therapeutics in clinical trials, there is an urgency to improve diagnostics and monitor therapeutic efficacy with biomarkers. In this study, we sought to define the structure of an unknown lipid biomarker for NPC1 with [M + H] + ion at m/z 509.3351, previously designated as lysoSM-509. The structure of N -palmitoyl- O -phosphocholineserine (PPCS) was proposed for the lipid biomarker based on the results from mass spectrometric analyses and chemical derivatizations. As no commercial standard is available, authentic PPCS was chemically synthesized, and the structure was confirmed by comparison of endogenous and synthetic compounds as well as their derivatives using liquid chromatography-tandem mass spectrometry (LC-MS/MS). PPCS is the most abundant species among N -acyl- O -phosphocholineserines (APCS), a class of lipids that have not been previously detected in biological samples. Further analysis demonstrated that all APCS species with acyl groups ranging from C14 to C24 were elevated in NPC1 plasma. PPCS is also elevated in both central and peripheral tissues of the NPC1 cat model. Identification of APCS structures provide an opportunity for broader exploration of the roles of these novel lipids in NPC1 disease pathology and diagnosis., (Copyright © 2019 Sidhu et al.)

Fragile X-associated disorders encompass several conditions, which are caused by expansion mutations in the fragile X mental retardation 1 (FMR1) gene. Fragile X syndrome is the most common inherited etiology of intellectual disability and results from a full mutation or >200 CGG repeats in FMR1. It is associated with developmental delay, autism spectrum disorder, and seizures. Fragile X-associated tremor/ataxia syndrome is a progressive neurodegenerative disease that occurs in premutation carriers of 55-200 CGG repeats in FMR1 and is characterized by kinetic tremor, gait ataxia, parkinsonism, executive dysfunction, and neuropathy. Fragile X-associated primary ovarian insufficiency also occurs in premutation carrier women and manifests with infertility and early menopause. The diseases constituting fragile X-associated disorders differ mechanistically, due to the distinct molecular properties of premutation versus full mutations. Fragile X syndrome occurs when there is a lack of fragile X mental retardation protein (FMRP) due to FMR1 methylation and silencing. In fragile X-associated tremor ataxia syndrome, a toxic gain of function is postulated with the production of excess CGG repeat-containing FMR1 mRNA, abnormal translation of the repeat sequence leading to production of polyglycine, polyalanine, and other polypeptides and to outright deficits in translation leading to reduced FMRP at larger premutation sizes. The changes in underlying brain chemistry due to FMR1 mutations have led to therapeutic studies in these disorders, with some progress being made in fragile X syndrome. This paper also summarizes indications for testing, genetic counseling issues, and what the future holds for these disorders., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Niemann-Pick disease, type C1 (NPC1) is a lysosomal storage disorder characterised by progressive neurodegeneration. In preclinical testing, 2-hydroxypropyl-β-cyclodextrins (HPβCD) significantly delayed cerebellar Purkinje cell loss, slowed progression of neurological manifestations, and increased lifespan in mouse and cat models of NPC1. The aim of this study was to assess the safety and efficacy of lumbar intrathecal HPβCD., Methods: In this open-label, dose-escalation phase 1-2a study, we gave monthly intrathecal HPβCD to participants with NPC1 with neurological manifestation at the National Institutes of Health (NIH), Bethesda, MD, USA. To explore the potential effect of 2-week dosing, three additional participants were enrolled in a parallel study at Rush University Medical Center (RUMC), Chicago, IL, USA. Participants from the NIH were non-randomly, sequentially assigned in cohorts of three to receive monthly initial intrathecal HPβCD at doses of 50, 200, 300, or 400 mg per month. A fifth cohort of two participants received initial doses of 900 mg. Participants from RUMC initially received 200 or 400 mg every 2 weeks. The dose was escalated based on tolerance or safety data from higher dose cohorts. Serum and CSF 24(S)-hydroxycholesterol (24[S]-HC), which serves as a biomarker of target engagement, and CSF protein biomarkers were evaluated. NPC Neurological Severity Scores (NNSS) were used to compare disease progression in HPβCD-treated participants relative to a historical comparison cohort of 21 NPC1 participants of similar age range., Findings: Between Sept 21, 2013, and Jan 19, 2015, 32 participants with NPC1 were assessed for eligibility at the National Institutes of Health. 18 patients were excluded due to inclusion criteria not met (six patients), declined to participate (three patients), pursued independent expanded access and obtained the drug outside of the study (three patients), enrolled in the RUMC cohort (one patient), or too late for the trial enrolment (five patients). 14 patients were enrolled and sequentially assigned to receive intrathecal HPβCD at a starting dose of 50 mg per month (three patients), 200 mg per month (three patients), 300 mg per month (three patients), 400 mg per month (three patients), or 900 mg per month (two patients). During the first year, two patients had treatment interrupted for one dose, based on grade 1 ototoxicity. All 14 patients were assessed at 12 months. Between 12 and 18 months, one participant had treatment interrupted at 17 months due to hepatocellular carcinoma, one patient had dose interruption for 2 doses based on caregiver hardship and one patient had treatment interrupted for 1 dose for mastoiditis. 11 patients were assessed at 18 months. Between Dec 11, 2013, and June 25, 2014, three participants were assessed for eligibility and enrolled at RUMC, and were assigned to receive intrathecal HPβCD at a starting dose of 200 mg every 2 weeks (two patients), or 400 mg every two weeks (one patient). There were no dropouts in this group and all 3 patients were assessed at 18 months. Biomarker studies were consistent with improved neuronal cholesterol homoeostasis and decreased neuronal pathology. Post-drug plasma 24(S)-HC area under the curve (AUC 8-72 ) values, an indicator of neuronal cholesterol homoeostasis, were significantly higher than post-saline plasma 24(S)-HC AUC 8-72 after doses of 900 mg (p=0·0063) and 1200 mg (p=0·0037). CSF 24(S)-HC concentrations in three participants given either 600 or 900 mg of HPβCD were increased about two fold (p=0·0032) after drug administration. No drug-related serious adverse events were observed. Mid-frequency to high-frequency hearing loss, an expected adverse event, was documented in all participants. When managed with hearing aids, this did not have an appreciable effect on daily communication. The NNSS for the 14 participants treated monthly increased at a rate of 1·22, SEM 0·34 points per year compared with 2·92, SEM 0·27 points per year (p=0·0002) for the 21 patient comparison group. Decreased progression was observed for NNSS domains of ambulation (p=0·0622), cognition (p=0·0040) and speech (p=0·0423)., Interpretation: Patients with NPC1 treated with intrathecal HPβCD had slowed disease progression with an acceptable safety profile. These data support the initiation of a multinational, randomised, controlled trial of intrathecal HPβCD., Funding: National Institutes of Health, Dana's Angels Research Trust, Ara Parseghian Medical Research Foundation, Hope for Haley, Samantha's Search for the Cure Foundation, National Niemann-Pick Disease Foundation, Support of Accelerated Research for NPC Disease, Vtesse, Janssen Research and Development, a Johnson & Johnson company, and Johnson & Johnson., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The purpose of this study was to determine the frequency of fragile X mental retardation 1 (FMR1) premutation size expansions in individuals with Alzheimer's disease (AD) and other cognitive disorders compared with control subjects. FMR1 genetic screening was completed in patients being seen in a neurobehavioral or AD clinics. Appropriate controls were also collected. A second cohort was a community based, autopsy confirmed, sample of individuals with normal cognitive function, mild cognitive impairment, or AD. There was not an increased frequency of FMR1 expansions in individuals with cognitive disorders, including AD, compared with control subjects., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Myotonic dystrophy type 1 (DM1) is caused by expansion of a CTG triplet repeat in the 3' untranslated region of the DMPK gene that encodes a serine-threonine kinase. Patients with larger repeats tend to have a more severe phenotype. Clinical laboratories require reference and quality control materials for DM1 diagnostic and carrier genetic testing. Well-characterized reference materials are not available. To address this need, the Centers for Disease Control and Prevention-based Genetic Testing Reference Material Coordination Program, in collaboration with members of the genetic testing community, the National Registry of Myotonic Dystrophy and Facioscapulohumeral Muscular Dystrophy Patients and Family Members, and the Coriell Cell Repositories, has established and characterized cell lines from patients with DM1 to create a reference material panel. The CTG repeats in genomic DNA samples from 10 DM1 cell lines were characterized in three clinical genetic testing laboratories using PCR and Southern blot analysis. DMPK alleles in the samples cover four of five DM1 clinical categories: normal (5 to 34 repeats), mild (50 to 100 repeats), classical (101 to 1000 repeats), and congenital (>1000 repeats). We did not identify or establish Coriell cell lines in the premutation range (35 to 49 repeats). These samples are publicly available for quality control, proficiency testing, test development, and research and should help improve the accuracy of DM1 testing., (Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Purpose: Diagnostic and predictive testing for Huntington disease requires an accurate measurement of CAG repeats in the HD (IT15) gene. However, precise repeat sizing can be technically challenging, and is complicated by the lack of quality control and reference materials (RM). The aim of this study was to characterize genomic DNA from 14 Huntington cell lines available from the National Institute of General Medical Sciences Human Genetic Cell Repository at the Coriell Cell Repositories for use as reference materials for CAG repeat sizing., Methods: Fourteen Huntington cell lines were selected for study. The alleles in these materials represent a large range of sizes that include important diagnostic cutoffs and allele combinations. The allele measurement study was conducted by ten volunteer laboratories using a variety of polymerase chain reaction-based in-house developed methods and by DNA sequence analysis., Results: The Huntington alleles in the 14 genomic DNA samples range in size from 15 to 100 CAG repeats. There was good agreement among the ten laboratories, and thus, the 95% confidence interval was small for each measurement. The allele size determined by DNA sequence analysis agreed with the laboratory developed tests., Conclusion: These DNA materials, which are available from Coriell Cell Repositories, will facilitate accurate and reliable Huntington genetic testing.

Objective: To assess growth and seizure reduction in epileptic children using the ketogenic diet as a treatment for intractable epilepsy., Design: A retrospective chart review was designed to evaluate urinary ketone levels, height and weight z scores and percentiles, and seizure reduction. Data were collected at baseline and at 6 and 12 months., Subjects/settings: Fifty-seven subjects, ages 1 to 26 years old, started the ketogenic diet at Rush University Medical Center between August 1995 and December 2001. Thirty-nine subjects stayed on the diet for 6 months, and five more were lost by the 12th month of follow-up. Statistical analysis Mann-Whitney U tests assessed differences between male and female subjects and between subjects with high ketosis and moderate ketosis. Friedman tests followed by Wilcoxon sign rank tests assessed the significance of changes in growth at baseline and at 6 and 12 months. Associations between seizure reduction and growth and urinary ketone levels were determined using chi 2 tests. A binary logistic regression model identified potential predictors of growth and seizure reduction., Results: Height-for-age z scores significantly decreased ( P < or =.0005) from -0.30+/-1.19 to -0.99+/-1.13 among subjects on the diet for 12 months. Subjects with high ketosis (80 to 160 mg/dL) experienced a significant decrease ( P < or =.0005) in height-for-age z scores from -0.45+/-1.28 to -1.1+/-1.23, whereas subjects with moderate ketosis did not. Observed percent seizure reduction was similar to those of other published studies., Conclusions: Subjects on the ketogenic diet showed a delay in growth. More research is needed to evaluate the relationship between ketosis and growth.

Signal transduction cascades initiated by the neuronal kappa opioid receptor were studied following transfection of a neuronal (hippocampal) line, HN2, and the non-neural CHOs. Retinoic-acid mediated differentiation resulted in intense staining of the HN2 cells with a neurofilament protein antibody SMI 33 but not with an antibody to GFAP, thus establishing neuronal characteristics of the HN2 cell line. The kappa opioid receptor was stably expressed in the two cell lines by electroporation mediated transfer of a Cytomegalovirus-promoter driven construct, pCMV-kappa, harboring the kappa-opioid receptor cDNA. Positive clones (HN2 kappa 24 and CHO kappa 18) from both lines showed high expression of the kappa opioid receptor, as identified by [3H] U-69,593 binding to membranes prepared from HN2 kappa 24 and CHO kappa 18. Scatchard analysis revealed the presence of high affinity kappa opioid receptors in both engineered cell lines (KD=1.3 nM for HN2 kappa 24 and 2.1 nM for CHO kappa 18). Functional coupling to adenylate cyclase was displayed by 1 microM U-69,593 mediated inhibition (55-63%) of prostaglandin E1-stimulated intracellular cAMP levels. A major difference between the two clones was observed in functional coupling of the expressed kappa opioid receptor to phospholipases C (PL-C) and D (PL-D). U-69,593 (1 microM) treatment stimulated PL-C, but not PL-D, in HN2 kappa 24 cells, whereas PL-D, but not PL-C, was stimulated following such treatment of CHO kappa 18 cells. Our results using the model neuronal system, HN2 kappa 24, demonstrate cell-type specific, positive coupling of the kappa opioid receptor to the major Ca2+ mobilizing system, the PL-C cascade, which regulates neuronal firing.

The present case study features an adult male who was diagnosed with fragile X syndrome after the identification of this syndrome in his more affected brother. The patient presented with a Full Scale IQ within the broad range of normal and has been diagnosed with a schizotypal personality disorder. He shows significant deficits in the social and emotional aspects of daily life, but has striking cognitive strengths relating to reading and vocabulary as compared to most males affected with fragile X syndrome. DNA testing of blood leukocytes revealed that he has a fully expanded FMR1 CGG repeat mutation associated with almost complete lack of methylation. Protein studies demonstrate a limited production of FMRP, the protein produced by the FMR1 gene. It is believed that the near absence of methylation of the fully expanded mutation and the resultant expression of the FMR1 protein is responsible for the strong cognitive abilities of this fragile X patient.

Stable expression of neuronal receptors in cell lines of neural origin is important for studies of neurotransmitter mediated signal transduction. We have achieved this for the first time in three cell lines which are derived from various tissues of neural origin (hippocampus, HN2; chinese hamster brain explant, NCB-20; rat dorsal root ganglion, F-11). Following electroporation assisted transfer of a construct containing the hippocampal serotonin 5-HT1A receptor (5-HT1AR) DNA, one neural cell line, NG-108-15 (murine neuroblastoma x C6 glioma), failed to express the transfected activity, while three others as well as the non-neural CHO (chinese hamster ovary) cells expressed high levels of the receptor. Upon normalization to coexpressed human beta-hexosaminidase B activity, it was found that the human 5-HT1AR, which is normally concentrated in the hippocampus and at a lesser density in the brain, was expressed at the highest level (15.7 x 10(4) receptors/cell) in the HN2 followed by the NCB-20 (8.3 x 10(4) receptors/cell), F-11 (4.4 x 10(4) receptors/cell) and lastly the non-neuronal CHO (4.2 x 10(4) receptors/cell) cells. Ten-twelve days after passage, a striking increase in expression of the receptor was observed only in the cell lines of neural origin. By contrast, there was no appreciable increase in expression of the transfected 5-HT1AR in the non-neural CHO cells over time. This late increase in expression was eliminated in cells which had been maintained in low glucose (1 g/L) for the first two days after passage, thus establishing a vital role of glucose in expression of the transfected 5-HT1AR in cell lines of neural origin. In all cases the 5-HT1AR was negatively coupled to adenylate cyclase, as evidenced by an agonist mediated decrease in prostaglandin E1 stimulated cyclic AMP levels.

Platelet serotonin (5-HT) studies were conducted with 12 hyperserotonemic and 12 normoserotonemic age-, sex-, and relationship-matched relatives of autistic probands. Each group consisted of 7 mothers, 4 fathers, and 1 sister of autistic children and adolescents. The density (Bmax) of platelet 5-HT2 receptor binding sites, labelled with [3H]-lysergic acid diethylamide (LSD), was significantly lower in 11 hyperserotonemic subjects compared to 12 normoserotonemic subjects (40.9 +/- 13.5 fmol/mg protein, 59.6 +/- 13.2; p < 0.004). The affinity (Kd) for [3H]-LSD binding did not differ. Although the density (Bmax) of [3H]-paroxetine binding did not differ between groups, there was a small difference in the affinity (Kd) for [3H]-paroxetine binding (hyperserotonemic 47.6 +/- 9.0 pM, normoserotonemic 54.8 +/- 12.1; p < 0.05). There were no significant differences in platelet 5-HT uptake, or in thrombin-stimulated 5-HT release. Basal, 5-HT-stimulated, and arginine-vasopressin (AVP)-stimulated inositol phosphate production, as well as basal, prostaglandin E1 (PGE1)-, and forskolin-stimulated cAMP production did not differ. There were significant correlations between whole blood 5-HT levels and LSD Bmax (rs = -0.63, N = 23, p < 0.002) and whole blood 5-HT levels and 5-HT uptake Vmax (rs = 0.56, N = 18, p < 0.02). However, [3H]-LSD labelled 5-HT2 binding and 5-HT uptake were not correlated with each other. Hyperserotonemia of autism may be heterogeneous with one subgroup of subjects with increased 5-HT uptake and another subgroup with decreased 5-HT2 binding.

Specific binding of [3H][D-Ala2,D-Leu5]enkephalin, [3H]ethylketocyclazocine, 5-[3H]hydroxytryptamine, and [3H]spiperone was examined in neuroblastoma-brain hybrid cell line NCB-20 following exposure to inhibitors of N-linked protein glycosylation (tunicamycin, TM) and oligosaccharide processing (swainsonine, SW). TM treatment reduced ligand binding at delta- and sigma-opiate receptors and neuroleptic binding sites (20 to 50% of control), with no discernible effect on the binding properties of 5HT1-serotonin receptors. In contrast, exposure to SW resulted in a three-fold increase in binding capacity of sigma-receptors, while decreasing receptor affinity for ligand. SW treatment did not alter ligand interactions with either sigma-receptors or neuroleptic binding sites, but did reduce specific binding of serotonin to 5HT1-receptors. The effects of TM and SW on distinct receptor subpopulations were further demonstrated by attenuation of opiate and serotonin-mediated regulation of intracellular cyclic AMP.