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The thrombotic risk with haemoglobin C trait (HbAC) or haemoglobin C disease (HbCC) is unclear. However, individuals with HbCC have demonstrated chronic haemolysis, higher blood viscosity and altered rheology when compared to individuals with wild-type haemoglobin (HbAA). These physiological alterations may theoretically translate to increased risk of thrombosis; therefore, a systematic literature review was performed to investigate the possible association between HbAC and/or HbCC and thrombosis. Twenty-two studies met inclusion criteria representing 782 individuals with HbAC (n = 694) or HbCC (n = 88). Fifteen studies described the presence/absence of venous thromboembolism (VTE) in patients with HbAC (n = 685) or HbCC (n = 79), while seven studies described patients with HbAC (n = 9) or HbCC (n = 9) and arterial thrombosis. Most (n = 20) studies were case reports or case series; however, two studies suggested a potential increased VTE risk with HbAC compared to HbAA in (i) all patients (OR 2.2, 95% CI: 0.9-5.5) and in (ii) pregnant individuals (RR 3.7, 95% CI 0.9-16). This review is the largest assessment of patients with HbC trait or disease and thrombosis to date; despite its limitations, the findings suggest HbC may be a predisposing risk factor to thrombosis. Prospective cohort studies are warranted to definitively elucidate the risk of thrombosis in this population., (© 2024 British Society for Haematology and John Wiley & Sons Ltd.)

Invasive meningococcal disease (IMD) is caused by the gram-negative bacterium Neisseria meningitidis. Infection cause invasive and life-threatening infection including meningitis and meningococcaemia (1,2). IMD is caused by bloodstream invasion of [...]

Niemann Pick Type C disease is a rare and progressive neurodegenerative lysosomal storage disorder caused by autosomal recessive mutations in the NPC1 and NPC2 genes. It is characterized by the accumulation of multiple lipid species in the endolysosomal compartment, leading to neurodegeneration and involvement of the liver, spleen, and lungs. Niemann Pick Type C has a wide range of presentations and severities at different ages with different progression rates. According to the Human Gene Mutation Database, to date, 486 disease-causing mutations in the highly polymorphic NPC1 gene and >20 mutations in the NPC2 have been reported. In the present study, we described the clinical, biochemical, and molecular profiles of 18 Iranian patients with Niemann-Pick Type C disease. Also, we describe six novel variants of the NPC1 gene, to our knowledge, not reported to date.

Lysosomes communicate through cholesterol transfer at endoplasmic reticulum (ER) contact sites. At these sites, the Niemann Pick C1 cholesterol transporter (NPC1) facilitates the removal of cholesterol from lysosomes, which is then transferred to the ER for distribution to other cell membranes. Mutations in NPC1 result in cholesterol buildup within lysosomes, leading to Niemann-Pick Type C (NPC) disease, a progressive and fatal neurodegenerative disorder. The molecular mechanisms connecting NPC1 loss to NPC-associated neuropathology remain unknown. Here we show both in vitro and in an animal model of NPC disease that the loss of NPC1 function alters the distribution and activity of voltage-gated calcium channels (CaV). Underlying alterations in calcium channel localization and function are KV2.1 channels whose interactions drive calcium channel clustering to enhance calcium entry and fuel neurotoxic elevations in mitochondrial calcium. Targeted disruption of KV2-CaV interactions rescues aberrant CaV1.2 clustering, elevated mitochondrial calcium, and neurotoxicity in vitro. Our findings provide evidence that NPC is a nanostructural ion channel clustering disease, characterized by altered distribution and activity of ion channels at membrane contacts, which contribute to neurodegeneration.

Niemann-Pick type C (NPC) disease is an inherited lysosomal storage disorder mainly driven by mutations in the NPC1 gene, causing lipid accumulation within late endosomes/lysosomes and resulting in progressive neurodegeneration. Although microglial activation precedes neuronal loss, it remains elusive whether loss of the membrane protein NPC1 in microglia actively contributes to NPC pathology. In a mouse model with depletion of NPC1 in myeloid cells, we report severe alterations in microglial lipidomic profiles, including the enrichment of bis(monoacylglycero)phosphate, increased cholesterol, and a decrease in cholesteryl esters. Lipid dyshomeostasis was associated with microglial hyperactivity, marked by an increase in translocator protein 18 kDa (TSPO). These hyperactive microglia initiated a pathological cascade resembling NPC-like phenotypes, including a shortened life span, motor impairments, astrogliosis, neuroaxonal pathology, and increased neurofilament light chain (NF-L), a neuronal injury biomarker. As observed in the mouse model, patients with NPC showed increased NF-L in the blood and microglial hyperactivity, as visualized by TSPO-PET imaging. Reduced TSPO expression in blood-derived macrophages of patients with NPC was measured after N -acetyl-l-leucine treatment, which has been recently shown to have beneficial effects in patients with NPC, suggesting that TSPO is a potential marker to monitor therapeutic interventions for NPC. Conclusively, these results demonstrate that myeloid dysfunction, driven by the loss of NPC1, contributes to NPC disease and should be further investigated for therapeutic targeting and disease monitoring.

Niemann-Pick Type-C (NPC) disease, an autosomal recessive lysosomal storage disorder, is associated with a spectrum of neuropsychiatric manifestations, including catatonia, which may not respond to conventional treatment. Here we report the case of a patient with adult-type NPC disease who developed catatonia and experienced recurrent catatonic episodes after the administration of antipsychotics required to treat active psychotic symptoms. Despite unsuccessful attempts with lorazepam, clozapine, and memantine to treat the catatonic symptoms, the patient showed improvement with electroconvulsive therapy (ECT). Catatonia recurred shortly after ECT discontinuation and improved with resuming ECT and adding lorazepam. However, catatonia recurred when the ECT frequency was reduced. We were able to resolve the catatonia with a combination of ECT and lorazepam. However, when we reduced the frequency of ECT sessions, the catatonia recurred despite continued lorazepam treatment. Remarkably, the addition of lamotrigine to the patient's treatment resulted in complete remission with no further recurrence of catatonia for 8 months. Our case highlights lamotrigine's mood-stabilizing effect and possible anti-NMDA effect in treating and preventing recurrent catatonia.

Objective: A range of neuropathological changes occur in the brains of individuals with adult Niemann-Pick type C disease (NPC), a recessive disorder of cholesterol trafficking that results in accumulation of cholesterol and gangliosides in lysosomes, particularly in neurons. One of the most significant regions of grey matter loss occurs in the thalami, which abut the midline. What is not known is whether these are neurodevelopmental in origin well prior to symptomatic onset. We aimed to examine other markers of midline developmental anomalies in adults with NPC. Method: We examined the size of adhesio interthalamica (AI) and cavum septum pellucidum (CSP) (if present) in nine individuals diagnosed with NPC and nine healthy comparison subjects, matched for age and gender, using a 3T magnetic resonance volumetric sequence and measured the length of the AI and CSP in mm. Results: We found that 5/9 NPC patients and 0/9 controls had a missing AI. AI length was significantly shorter in the patient group. No subject in other group had a large CSP, and CSP length did not differ. Duration of illness showed a trend to a negative correlation with AI length in patients. Conclusions: Our findings suggest that adult NPC patients show some markers of early neurodevelopmental disturbance, matching findings seen in psychotic disorders. The differences in AI, but not CSP, suggest neurodevelopmental change may occur early in gestation rather than post-partum. The relationship with duration of illness suggests that there may be atrophy over time in these structures, consistent with prior analyses of grey matter regions in NPC. [ABSTRACT FROM AUTHOR]

Cobalamin C disease is the most common complementation class of cobalamin disorders. Here, we present a case of a 14-yr-old male with early-onset cblC disease and autism spectrum disorder (ASD) admitted to our inpatient medical service for behavioral decompensation. We use this case to highlight key aspects of the neurodevelopmental and neuropsychiatric disorders associated with cblC disease. By incorporating a comprehensive review of existing literature, we highlight salient domains of psychological impairment in cblC disease, discuss the full range of neuropsychiatric presentations, and review clinical management implications unique to cblC disease.

Niemann-Pick type C (NPC) is a lysosomal storage disorder (LSD) caused by pathogenic variants in either the NPC1 or NPC2 genes, which encode proteins involved in the lysosomal export of unesterified cholesterol. In patients of Western European descent, the p.Ile1061Thr variant in NPC1 is especially prevalent. However, mounting evidence has positioned p.Ala1035Val as the most common variant in Portugal and the second most prevalent variant worldwide. By analyzing 10 Portuguese NPC patients homozygous for p.Ala1035Val, we found an SNP in cis on position 858 (p.Ile858Val), which we hypothesize could have a disease-modifying effect. To address this query, we created variant-specific in vitro models of NPC by stably transducing NPC1 -/- ARPE-19 cells with constructs encoding different fluorescently-tagged variants of NPC1, which we used, alongside patient-derived skin fibroblasts, to investigate lysosomal positioning and the trafficking routes elicited by p.Ile1061Thr and p.Ala1035Val (with and without the p.Ile858Val SNP in cis ). Our results corroborate the previously described decrease in p.Ile1061Thr-NPC1 trafficking to the lysosome and suggest a similar, if not worse, scenario for the p.Ala1035Val variant, especially when in cis with p.Ile858Val. This is the first reported functional study addressing the impact of the p.Ala1035Val variant at the cellular level, paving the way for novel therapeutic options.

Introduction: HbC is a common structural hemoglobinopathy especially in West Africa. Prevalence and regional distribution of HbC in Saudi Arabia are widely undocumented. Patients with homozygous HbC disease may have mild hemolytic anemia whereas combination with hemoglobin S (HbS) leads to a clinically severe phenotype., Aim: The current epidemiological study, considered the largest from Saudi Arabia, aimed to evaluate the regional prevalence of the HbC variant among the couples participating in the premarital screening program from 2011 to 2018., Methods: Data from the PMSGC program were obtained for premarital screening and genetic counseling. The collected data were then entered into the SEHA platform, a centralized electronic repository for the 13 designated regions in Saudi Arabia. Hemoglobin electrophoresis samples are analyzed using either HPLC, capillary electrophoresis, or a combination of both methods to confirm the presence of abnormal hemoglobin bands., Results: This study included 1,871,184 individuals from 2011 to 2018. Of those, 49.8% were males and 50.2% were females. 112,618 (6.0%) had an abnormal test. Total number of Hb C cases were 778 (0.04%). HbC trait (HbAC) was detected in 764 participants while homozygous HbC (HbCC) and combined heterozygous (HbSC) were found in 9 and 5 cases, respectively. The regions near the Red Sea have higher rates than the central and eastern regions., Conclusion: HbC is a rare variant in Saudi Arabia with varying regional frequencies. HbC variant is more common in Mecca and Madina regions. The geographic area of HbC distribution differs from the areas with high prevalence of HbS, which explains why HbSC disease cases are overwhelmingly rare., (© 2024. The Author(s).)

Hepatitis C is a liver disease caused by infection with the hepatitis C virus (HCV), which is transmitted through the blood. The disease can lead to diseases ranging from a mild form to serious lifelong illness. Studies to detect the disease early and reduce its effect are continuing. This study proposes an effective support vector machine model supported by principal component analysis for detecting hepatitis c disease. The dataset consisted of twelve independent variables, each containing 582 samples, and these variables were used as inputs to the two classifiers, support vector machine (SVM) and artificial neural network (ANN). The accuracy, sensitivity, specificity, MCC and KAPPA were calculated using two classification models. In addition, performance comparisons of classifiers were made for the two cases with and without PCA (principal component analysis) applied to the inputs. The highest accuracy (98.7%), sensitivity (99.1%), specificity (95.2%), MCC (92.3%) and Kappa (92.3%) in the binary class label were obtained with the SVM with PCA. In the four-class label, the highest accuracy was achieved with the same model with 95.7%. The results show that an SVM classifier model, in which PCA-reduced independent variables are applied to its inputs, may be a candidate for an accurate prediction model to predict hepatitis C disease.

Background: Niemann-Pick type C (NPC) disease is a lysosomal storage disease with visceral organ involvement and neurological and psychiatric symptoms. This study presents the clinical and laboratory findings of NPC cases involving three novel variants., Methods: The clinical and laboratory findings were reviewed retrospectively between February 2006 and December 2022., Results: There were nine females and five males. The median age of diagnosis of the patients was 5 months (range: 1 month to 38 years). The clinical phenotypes of the patients were early infantile (n = 7), late infantile (n = 4), juvenile (n = 2), and adult (n = 1). The visceral findings were splenomegaly (100%), hepatomegaly (78.6%), neonatal jaundice (42.8%), and hepatic failure (14.3%). The neurological findings were developmental delay (71.4%), seizures (50%), vertical supranuclear gaze palsy (28.6%), ataxia (28.6%), dysarthria (28.6%), dysphagia (21.4%), dystonia (21.4%). Cataplexy (14.3%) and psychiatric manifestations (14.3%) were recorded in juvenile and adult-onset patients. Three novel variants were detected (p.Asn524LysfsTer39, p.Val1023Phe, and p.Asn906Tyr). Miglustat treatment was received by 64.3% of patients but had no clear effect on the disease course. The median duration of use was 3 years (with a range from 1-13 years). Miglustat's adverse effects were low platelet count (35.7%) and diarrhea (7.1%)., Conclusions: Niemann-Pick type C disease should be considered in the presence of visceral organ involvement and progressive neurological findings. It is essential to support the diagnosis with laboratory and genetic analysis., (© 2024 Japan Pediatric Society.)

Since its first description in 1906 by Dr. Alois Alzheimer, Alzheimer's disease (AD) has been the most common type of dementia. Initially thought to be caused by age-associated accumulation of plaques, in recent years, research has increasingly associated AD with lysosomal storage and metabolic disorders, and the explanation of its pathogenesis has shifted from amyloid and tau accumulation to oxidative stress and impaired lipid and glucose metabolism aggravated by hypoxic conditions. However, the underlying mechanisms linking those cellular processes and conditions to disease progression have yet to be defined. Here, we applied a disease similarity approach to identify unknown molecular targets of AD by using transcriptomic data from congenital diseases known to increase AD risk, namely Down Syndrome, Niemann Pick Disease Type C (NPC), and Mucopolysaccharidoses I. We uncovered common pathways, hub genes, and miRNAs across in vitro and in vivo models of these diseases as potential molecular targets for neuroprotection and amelioration of AD pathology, many of which have never been associated with AD. We then investigated common molecular alterations in brain samples from an NPC disease mouse model by juxtaposing them with brain samples of both human and mouse models of AD. Detailed phenotypic and molecular analyses revealed that the NPC mut mouse model can serve as a potential short-lived in vivo model for AD research and for understanding molecular factors affecting brain aging. This research represents the first comprehensive approach to congenital disease association with neurodegeneration and a new perspective on AD research while highlighting shortcomings and lack of correlation in diverse in vitro models. Considering the lack of an AD mouse model that recapitulates the physiological hallmarks of brain aging, the characterization of a short-lived NPC mouse model will further accelerate the research in these fields and offer a unique model for understanding the molecular mechanisms of AD from a perspective of accelerated brain aging.

Niemann-Pick type C (NPC) disease is a rare progressive lysosomal lipid storage disorder that manifests with a heterogeneous spectrum of clinical syndromes, including visceral, neurological and psychiatric symptoms. This monogenetic autosomal recessive disease is largely caused by mutations in the NPC1 gene, which controls intracellular lipid homeostasis. Vesicle-mediated endo-lysosomal lipid trafficking and non-vesicular lipid exchange via inter-organelle membrane contact sites are both regulated by the NPC1 protein. Loss of NPC1 function therefore triggers intracellular accumulation of diverse lipid species, including cholesterol, glycosphingolipids, sphingomyelin and sphingosine. The NPC1-mediated dysfunction of lipid transport has severe consequences for all brain cells, leading to neurodegeneration. Besides the cell-autonomous contribution of neuronal NPC1, aberrant NPC1 signalling in other brain cells is critical for the pathology. We discuss here the importance of endo-lysosomal dysfunction and a tight crosstalk between neurons, oligodendrocytes, astrocytes and microglia in NPC pathology. We strongly believe that a cell-specific rescue may not be sufficient to counteract the severity of the NPC pathology, but targeting common mechanisms, such as endo-lysosomal and lipid trafficking dysfunction, may ameliorate NPC pathology. This article is part of a discussion meeting issue 'Understanding the endo-lysosomal network in neurodegeneration'.

Niemann-Pick Type C (NPC) represents an autosomal recessive disorder with an incidence rate of 1 in 150,000 live births, classified within lysosomal storage diseases (LSDs). The abnormal accumulation of unesterified cholesterol characterizes the pathophysiology of NPC. This phenomenon is not unique to NPC, as analogous accumulations have also been observed in Alzheimer's disease, Parkinson's disease, and other neurodegenerative disorders. Interestingly, disturbances in the folding of the mutant protein NPC1 I1061T are accompanied by the aggregation of proteins such as hyperphosphorylated tau, α-synuclein, TDP-43, and β-amyloid peptide. These accumulations suggest potential disruptions in proteostasis, a regulatory process encompassing four principal mechanisms: synthesis, folding, maintenance of folding, and protein degradation. The dysregulation of these processes leads to excessive accumulation of abnormal proteins that impair cell function and trigger cytotoxicity. This comprehensive review delineates reported alterations across proteostasis mechanisms in NPC, encompassing changes in processes from synthesis to degradation. Additionally, it discusses therapeutic interventions targeting pharmacological facets of proteostasis in NPC. Noteworthy among these interventions is valproic acid, a histone deacetylase inhibitor (HDACi) that modulates acetylation during NPC1 synthesis. In addition, various therapeutic options addressing protein folding modulation, such as abiraterone acetate, DHBP, calnexin, and arimoclomol, are examined. Additionally, treatments impeding NPC1 degradation, exemplified by bortezomib and MG132, are explored as potential strategies. This review consolidates current knowledge on proteostasis dysregulation in NPC and underscores the therapeutic landscape targeting diverse facets of this intricate process.

Methylmalonic aciduria and homocystinuria type C protein (MMACHC) is required by the body to metabolize cobalamin (Cbl). Due to its complex structure and cofactor forms, Cbl passes through an extensive series of absorptive and processing steps before being delivered to mitochondrial methyl malonyl-CoA mutase and cytosolic methionine synthase. Depending on the cofactor attached, MMACHC performs either flavin-dependent reductive decyanation or glutathione (GSH)-dependent dealkylation. The alkyl groups of Cbl have to be removed in the presence of GSH to produce intermediates that can later be converted into active cofactor forms. Pathogenic mutations in the GSH binding site, such as R161Q, R161G, R206P, R206W, and R206Q, have been reported to cause Cbl diseases. The impact of these variations on MMACHC’s structure and how it affects GSH and Cbl binding at the molecular level is poorly understood. To better understand the molecular basis of this interaction, mutant structures involving the MMACHC-MeCbl-GSH complex were generated using in silico site-directed point mutations and explored using molecular dynamics (MD) simulations. The results revealed that mutations in the key arginine residues disrupt GSH binding by breaking the interactions and reducing the free energy of binding of GSH. Specifically, variations at position 206 appeared to produce weaker GSH binding. The lowered binding affinity for GSH in the variant structures could impact metabolic pathways involving Cbl and its trafficking.

The folding and trafficking of transmembrane glycoproteins are essential for cellular homeostasis and are compromised in many diseases. In Niemann-Pick type C disease, a lysosomal disorder characterized by impaired intracellular cholesterol trafficking, the transmembrane glycoprotein NPC1 misfolds due to disease-causing missense mutations. While mutant NPC1 has emerged as a robust target for proteostasis modulators, drug development efforts have been unsuccessful in mouse models. Here, we demonstrated unexpected differences in trafficking through the medial Golgi between mouse and human I1061T-NPC1, a common disease-causing mutant. We established that these distinctions are governed by differences in the NPC1 protein sequence rather than by variations in the endoplasmic reticulum–folding environment. Moreover, we demonstrated direct effects of mutant protein trafficking on the response to small molecules that modulate the endoplasmic reticulum–folding environment by affecting Ca++ concentration. Finally, we developed a panel of isogenic human NPC1 iNeurons expressing WT, I1061T-, and R934L-NPC1 and demonstrated their utility in testing these candidate therapeutics. Our findings identify important rules governing mutant NPC1’s response to proteostatic modulators and highlight the importance of species- and mutation-specific responses for therapy development.