Iron homeostasis and infIammatory biomarker analysis in patients with type 1 Gaucher disease

Real life data: follow-up assessment on Spanish Gaucher disease patients treated with eliglustat. TRAZELGA project

BACKGROUND

The availability of multiple treatments for type 1 Gaucher disease increases the need for real-life studies to evaluate treatment efficacy and safety and provide clinicians with more information to choose the best personalized therapy for their patients.

AIMS

To determine whether treatment with eliglustat produces, in adult GD1 patients, ans optimal response in daily clinical practice.

METHODS

We designed a real-life study with 2 years of follow-up (TRAZELGA [GEE-ELI-2017-01]) to uniformly evaluate the response and adverse events to eliglustat treatment. This study, conducted in 30 patients across Spain and previously treated with other therapies, included the evaluation of safety and efficacy by assessing visceral enlargement, bone disease (DEXA and T and Z scores), concomitant treatments and adverse events, as well as a quality of life evaluation (SF-36). In addition, the quantification of classical biomarkers (chitotriosidase activity, CCL18/PARC and glucosylsphingosine (GluSph)) and new candidates for GD biomarkers (YKL-40, cathepsin S, hepcidin and lipocalin-2 determined by immunoassay) were also assessed. Non-parametric statistical analysis was performed and p < 0.05 was considered statistically significant.

MAIN RESULTS

Thirty patients were enrolled in the study. The median age was 41.5 years and the male-female ratio was 1.1:1. 84% of the patients had received ERT and 16% SRT as previous treatment. The most common symptoms at baseline were fatigue (42%) and bone pain (38%), no patient had a bone crisis during the study, and two years after switching, 37% had reduced their use of analgesics. Patient-reported outcomes showed a significant increase in physical function scores (p = 0.027) and physical pain scores (p = 0.010). None of the enrolled patients discontinued treatment due to adverse events, which were mild and transient in nature, mainly gastrointestinal and skin dryness. None of the biomarkers show a significant increase or decompensation after switching. CCL18/PARC (p = 0.0012), YKL-40 (p = 0.00004) and lipocalin-2 (p = 0.0155) improved after two years and GluSph after one year (p = 0.0008) and two years (p = 0.0245) of oral therapy.

CONCLUSION

In summary, this real-life study, showed that eliglustat maintains stability and can improve quality of life with few side effects. Significant reductions in classic and other novel biomarkers were observed after two years of therapy.

Patient-reported outcomes in Gaucher's disease: a systematic review

BACKGROUND

Gaucher's disease (GD), a rare condition, represents the most common lysosomal storage disorder. The cardinal manifestations of GD are fatigue, hepatosplenomegaly, anemia, thrombocytopenia, bone pain, and bone infarction, thereby culminating in a marked deterioration of patients' quality of life (QoL). Patient-reported outcomes (PROs) offer valuable insights into the impact of GD on patients' QoL and symptoms. This systematic review aimed to identify and analyze PROs and outcome measures in GD patients.

METHODS

We systematically searched PubMed, Web of Science Core Collections, EMBASE, SCOPUS, Cochrane Library, PsycINFO, Wan Fang Data, China National Knowledge Infrastructure (CNKI), and the Chinese Biomedical Literature Database (CBM). The methodological quality of the included studies was assessed using a mixed methods assessment tool.

RESULTS

A total of 33 studies were identified, encompassing 24 distinct patient-reported outcome instruments, with the most frequently employed instrument being the SF-36. The study designs included eighteen cross-sectional studies, seven pre- and post-intervention investigations, three randomized controlled trials, two cohort studies, two qualitative inquiries, and one validation study. These studies explored diverse domains such as the QoL and cardinal symptoms (e.g., fatigue, pain, bleeding, cognition, social relationships, and psychological functioning) in patients with GD. Furthermore, significant attention was directed towards the appraisal of the therapeutic benefits of various interventions in patients with GD. A novel GD-specific instrument has also been developed, which has two applied versions: a 24-item variant for routine clinical monitoring and a 17-item form for use in clinical trials.

CONCLUSION

PROs have garnered increased attention and concern in the realm of GD. Despite this progress, it is noteworthy that the instruments used to measure PROs in GD are still predominantly generic instruments. While researchers have endeavored to develop and validate a disease-specific instrument, currently the use of this instrument is limited. Owing to several challenges, including the small number of patients, heterogeneity of the disease, and cross-regional discrepancies in study findings, GD poses substantial difficulties in the measurement of QoL and development of instruments. Consequently, patients with GD require more dependable measurement instruments that accurately reflect their QoL, efficacy of treatment, and facilitate healthcare decision-making.

Phagocytosis of Erythrocytes from Gaucher Patients Induces Phenotypic Modifications in Macrophages, Driving Them toward Gaucher Cells

Gaucher disease (GD) is caused by glucocerebrosidase deficiency leading to the accumulation of sphingolipids in macrophages named “Gaucher’s Cells”. These cells are characterized by deregulated expression of cell surface markers, abnormal secretion of inflammatory cytokines, and iron sequestration. These cells are known to infiltrate tissues resulting in hematological manifestations, splenomegaly, and bone diseases. We have already demonstrated that Gaucher red blood cells exhibit altered properties suggesting their key role in GD clinical manifestations. We hypothesized that Gaucher’s erythrocytes could be prone to premature destruction by macrophages contributing to the formation of altered macrophages and Gaucher-like cells. We conducted in vitro experiments of erythrophagocytosis using erythrocytes from Gaucher’s patients or healthy donors. Our results showed an enhanced erythrophagocytosis of Gaucher red blood cells compared to healthy red blood cells, which is related to erythrocyte sphingolipids overload and reduced deformability. Importantly, we showed elevated expression of the antigen-presenting molecules CD1d and MHC-II and of the iron-regulator hepcidin in macrophages, as well as enhanced secretion of the pro-inflammatory cytokine IL-1β after phagocytosis of GD erythrocytes. These results strongly suggested that erythrophagocytosis in GD contribute to phenotypic modifications in macrophages. This present study shows that erythrocytes-macrophages interactions may be crucial in GD pathophysiology and pathogenesis.

Hemochromatosis Mimicked Gaucher Disease: Role of Hyperferritinemia in Evaluation of a Clinical Case

Gaucher disease is a disorder of lysosomes caused by a functional defect of the glucocerebrosidase enzyme. The disease is mainly due to mutations in the GBA1 gene, which determines the gradual storage of glucosylceramide substrate in the patient's macrophages. In this paper, we describe the case of a 38-year-old man who clinically presented with hyperferritinemia, thrombocytopenia, leukopenia, anemia and mild splenomegaly; a diagnosis of hemochromatosis was made 10 years earlier. Re-evaluation of the clinical case led to a suspicion of Gaucher disease, which was confirmed by enzymatic analysis, which was found to be below the normal range, and genetic evaluation, which identified compound heterozygosity N370S/RecNciI. We know that patients suffering from Gaucher disease can also have high ferritin levels. Even if the mechanism underlying the changes in iron metabolism is not yet elucidated, the chronic mild inflammatory state present in these patients probably causes the storage of ferritin in macrophages, resulting in hyperferritinemia. Therefore, in the presence of few typical signs and symptoms of the disease should raise an alarm bell in the clinicians, inducing clinical suspicion of Gaucher disease. Misdiagnosis and diagnostic delay in metabolic diseases could cause irreversible organ damage and delay the start of specific therapy for these patients.

Novel Management and Screening Approaches for Haematological Complications of Gaucher's Disease

Purpose

Gaucher disease (GD) is the most common lysosomal storage disorder. The principal manifestations for its diagnosis and further monitoring include haematological manifestations such as anaemia, thrombocytopaenia, spleen enlargement, and bleeding disorders, among others. This review aims to summarise and update the role of haematological complications in GD diagnosis and follow-up, describe their management strategies, and to use these indicators as part of the diagnostic approach.

Materials and Methods

A systematic review following the recommendations of PRISMA-P 2020 was carried out. Publications indexed in the databases PubMed, Embase, Science Open, Mendeley, and Web of Science were electronically searched by three independent reviewers, and publications up to June 2021 were accessed. A total of 246 publications were initially listed, of which 129 were included for further review and analysis. Case reports were considered if they were representative of a relevant hematologic complication.

Results

From the first review dated in 1974 to the latest publication in 2021, including different populations confirmed that the haematological manifestations such as thrombocytopaenia and splenomegaly at diagnosis of GD type 1 are the most frequent features of the disease. The incorporation of haematological parameters to diagnosis strategies increases their cost-effectiveness. Hematologic parameters are part of the scoring system for disease assessment and the evaluation of therapeutic outcomes, providing reliable and accessible data to improve the management of GD. However, cytopaenia, underlying coagulation disorders, and platelet dysfunction need to be addressed, especially during pregnancy or surgery. Long-term haematological complications include the risk of neoplasia and immune impairment, an area of unmet need that is currently under research.

Conclusion

Haematological features are key for GD suspicion, diagnosis, and management. Normalization of hematological parameters is achieved with the treatment; however, there are unmet needs such as the underlying inflammatory status and the long-term risk of hematologic neoplasia.

Ferroptosis and Its Modulation by Autophagy in Light of the Pathogenesis of Lysosomal Storage Diseases

Ferroptosis is one of the recently described types of cell death which is dependent on many factors, including the accumulation of iron and lipid peroxidation. Its induction requires various signaling pathways. Recent discovery of ferroptosis induction pathways stimulated by autophagy, so called autophagy-dependent ferroptosis, put our attention on the role of ferroptosis in lysosomal storage diseases (LSD). Lysosome dysfunction, observed in these diseases, may influence ferroptosis efficiency, with as yet unknown consequences for the function of cells, tissues, and organisms, due to the effects of ferroptosis on physiological and pathological metabolic processes. Modulation of levels of ferrous ions and enhanced oxidative stress, which are primary markers of ferroptosis, are often described as processes associated with the pathology of LSD. Inhibition of autophagy flux and resultant accumulation of autophagosomes in neuronopathic LSD may induce autophagy-dependent ferroptosis, indicating a considerable contribution of this process in neurodegeneration. In this review article, we describe molecular mechanisms of ferroptosis in light of LSD, underlining the modulation of levels of ferroptosis markers in these diseases. Furthermore, we propose a hypothesis about the possible involvement of autophagy-dependent ferroptosis in these disorders.

Involvement of hepcidin in iron metabolism dysregulation in Gaucher disease

Gaucher disease (GD) is an inherited deficiency of glucocerebrosidase leading to accumulation of glucosylceramide in tissues such as the spleen, liver, and bone marrow. The resulting lipid-laden macrophages lead to the appearance of “Gaucher cells”. Anemia associated with an unexplained hyperferritinemia is a frequent finding in GD, but whether this pathogenesis is related to an iron metabolism disorder has remained unclear. To investigate this issue, we explored the iron status of a large cohort of 90 type I GD patients, including 66 patients treated with enzyme replacement therapy. Ten of the patients treated with enzyme replacement were followed up before and during treatment. Serum levels of hepcidin, the iron regulatory peptide, remained within the physiological range, while the transferrin saturation was slightly decreased in children. Inflammation-independent hyperferritinemia was found in 65% of the patients, and Perl’s staining of the spleen and marrow smear revealed iron accumulation in Gaucher cells. Treated patients exhibited reduced hyperferritinemia, increased transferrin saturation and transiently increased systemic hepcidin. In addition, the hepcidin and ferritin correlation was markedly improved, and, in most patients, the hemoglobin level was normalized. To further explore eventual iron sequestration in macrophages, we produce a Gaucher cells model by treating the J774 macrophage cell line with a glucocerebrosidase inhibitor and showed induced local hepcidin and membrane retrieval of the iron exporter, ferroportin. These data reveal the involvement of Gaucher cells in abnormal iron sequestration, which may explain the mechanism of hyperferritinemia in GD patients. Local hepcidin-ferroportin interaction was involved in this pathogenesis.

Vesicular melatonin efficiently downregulates sodium fluoride-induced rat hepato- and broncho-TNF-α, TGF-β expressions, and associated oxidative injury: a comparative study of liposomal and nanoencapsulated forms

The importance of fluoride as a natural and industrial toxicant is recognized worldwide. We evaluated the regulating role and biological effect of vesicular (liposomal and nanoencapsulated) melatonin (N-acetyl-5-methoxytryptamine) for drug delivery and controlled release on the depletion of inflammatory mediators, as well as oxidative damage in sodium fluoride (NaF)-treated lungs and liver. Hepatic and bronchial damage was induced in Swiss albino rats with a single acute ingestion of NaF (48 mg/kg body weight, oral gavage). NaF exposure caused the generation of reactive oxygen species (ROS); upregulation of TNF-α and TGF-β; decreased activities of antioxidant systems (glutathione, glutathione-S-transferase, superoxide dismutase, catalase), succinate dehydrogenase, membrane microviscosity, and membrane potential; increased activity of lipid peroxidation and nicotinamide adenine dinucleotide hydride oxidase; and increased hepatic and nephrite toxicities (P<0.001) compared to those in normal animals. Charge (-ve/+ve)-specific single liposomal (dicetyl phosphate/stearylamine) and nanoencapsulated melatonin (4.46 mg/kg body weight, intravenous) treatments (2 hours after NaF exposure) significantly (P<0.01/0.001) and maximally (P<0.001) inhibited all alterations developed in NaF-mediated oxidative injuries in rat liver (+ve) and lungs (-ve), demonstrating their strong free radical scavenging, antioxidant and antigenotoxic properties, and vesicular efficiencies of targeting. Overall, these results suggest that nanoencapsulated melatonin might be considered as a more powerful remedial therapy in comparison to liposomes, in terms of its efficacy in regulating NaF-intoxicated oxidative injury.

A Review of Gaucher Disease Pathophysiology, Clinical Presentation and Treatments

Gaucher disease (GD, ORPHA355) is a rare, autosomal recessive genetic disorder. It is caused by a deficiency of the lysosomal enzyme, glucocerebrosidase, which leads to an accumulation of its substrate, glucosylceramide, in macrophages. In the general population, its incidence is approximately 1/40,000 to 1/60,000 births, rising to 1/800 in Ashkenazi Jews. The main cause of the cytopenia, splenomegaly, hepatomegaly, and bone lesions associated with the disease is considered to be the infiltration of the bone marrow, spleen, and liver by Gaucher cells. Type-1 Gaucher disease, which affects the majority of patients (90% in Europe and USA, but less in other regions), is characterized by effects on the viscera, whereas types 2 and 3 are also associated with neurological impairment, either severe in type 2 or variable in type 3. A diagnosis of GD can be confirmed by demonstrating the deficiency of acid glucocerebrosidase activity in leukocytes. Mutations in the GBA1 gene should be identified as they may be of prognostic value in some cases. Patients with type-1 GD-but also carriers of GBA1 mutation-have been found to be predisposed to developing Parkinson's disease, and the risk of neoplasia associated with the disease is still subject to discussion. Disease-specific treatment consists of intravenous enzyme replacement therapy (ERT) using one of the currently available molecules (imiglucerase, velaglucerase, or taliglucerase). Orally administered inhibitors of glucosylceramide biosynthesis can also be used (miglustat or eliglustat).

Advances in GBA-associated Parkinson's disease--Pathology, presentation and therapies

GBA mutations are to date the most common genetic risk factor for Parkinson's disease. The GBA gene encodes the lysomal hydrolase glucocerebrosidase. Whilst bi-allelic GBA mutations cause Gaucher disease, both mono- and bi-allelic mutations confer risk for Parkinson's disease. Clinically, Parkinson's disease patients with GBA mutations resemble idiopathic Parkinson's disease patients. However, these patients have a modest reduction in age-of-onset of disease and a greater incidence of cognitive decline. In some cases, GBA mutations are also responsible for familial Parkinson's disease. The accumulation of α-synuclein into Lewy bodies is the central neuropathological hallmark of Parkinson's disease. Pathologic GBA mutations reduce enzymatic function. A reduction in glucocerebrosidase function increases α-synuclein levels and propagation, which in turn inhibits glucocerebrosidase in a feed-forward cascade. This cascade is central to the neuropathology of GBA-associated Parkinson's disease. The lysosomal integral membrane protein type-2 is necessary for normal glucocerebrosidase function. Glucocerebrosidase dysfunction also increases in the accumulation of β-amyloid and amyloid-precursor protein, oxidative stress, neuronal susceptibility to metal ions, microglial and immune activation. These factors contribute to neuronal death. The Mendelian Parkinson's disease genes, Parkin and ATP13A2, intersect with glucocerebrosidase. These factors sketch a complex circuit of GBA-associated neuropathology. To clinically interfere with this circuit, central glucocerebrosidase function must be improved. Strategies based on reducing breakdown of mutant glucocerebrosidase and increasing the fraction that reaches the lysosome has shown promise. Breakdown can be reduced by interfering with the ability of heat-shock proteins to recognize mutant glucocerebrosidase. This underlies the therapeutic efficacy of certain pharmacological chaperones and histone deacetylase inhibitors. These therapies are promising for Parkinson's disease, regardless of mutation status. Recently, there has been a boom in studies investigating the role of glucocerebrosidase in the pathology of Parkinson's disease. This merits a comprehensive review of the current cell biological processes and pathological pictures involving Parkinson's disease associated with GBA mutations.