Oxidative stress parameters of Gaucher disease type I patients

Oxidative and chromosomal DNA damage in patients with type I Gaucher disease and carriers

BACKGROUND AND AIMS

Gaucher disease (GD) is caused by a genetic deficiency of the beta-glucocerebrosidase enzyme which results in the accumulation of glucosylceramide in macrophages. This accumulation may induce oxidative stress, resulting in DNA damage in patients with GD. The aim of this study was to assess plasma 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels and cytokinesis-block micronucleus cytome (CBMN-cyt) assay parameters in the peripheral blood lymphocytes of patients with GD and carriers, evaluate the possible associations of these values with GD, and determine whether they can be used as potential biomarkers in GD.

METHODS

This study included 20 patients with type 1 GD, six carriers, and 27 age- and sex-matched healthy controls. CBMN-cyt assay parameters in peripheral blood lymphocytes of the patients with GD, carriers, and controls were evaluated and 8-OHdG levels in their plasma samples were measured.

RESULTS

CBMN-cyt assay parameters in patients with GD and carriers were not significantly different when compared with controls (p > 0.05). However, plasma 8-OHdG levels were found to be higher in both patients with GD and carriers than in control subjects (p < 0.01).

CONCLUSIONS

Oxidative DNA damage may be a useful prognostic tool, whereas the CBMN-cyt assay cannot be used as a predictive biomarker of GD.

Biological Variation in Peripheral Inflammation and Oxidative Stress Biomarkers in Individuals with Gaucher Disease

The lack of reliable biomarkers is a significant challenge impeding progress in orphan drug development. For appropriate interpretation of intervention-based results or for evaluating candidate biomarkers, other things being equal, lower variability in biomarker measurement would be helpful. However, variability in rare disease biomarkers is often poorly understood. Type 1 Gaucher disease (GD1) is one such rare lysosomal storage disorder. Oxidative stress and inflammation have been linked to the pathophysiology of GD1 and validated measures of these processes can provide predictive value for treatment success or disease progression. This study was undertaken to investigate and compare the extent of longitudinal biological variation over a three-month period for various blood-based oxidative stress and inflammation markers in participants with GD1 on stable standard-of-care therapy (N = 13), treatment-naïve participants with GD1 (N = 5), and in age- and gender-matched healthy volunteers (N = 18). We utilized Bland–Altman plots for visual comparison of the biological variability among the three measurements. We also report group-wise means and the percentage of coefficient of variation (%CV) for 15 biomarkers. Qualitatively, we show specific markers (IL-1Ra, IL-8, and MIP-1b) to be consistently altered in GD1, irrespective of therapy status, highlighting the need for adjunctive therapies that can target and modulate these biomarkers. This information can help guide the selection of candidate biomarkers for future intervention-based studies in GD1 patients.

New correlations between ocular parameters and disease severity in Spanish patients with Gaucher's disease Type I

Background

Gaucher’s disease is associated with a high variety of structural and functional abnormalities in the eye, which do not always affect visual acuity. The purpose of this study was to analyse ocular features in Spanish patients with Gaucher’s disease type I, and to investigate their possible correlation with phenotypic and burden parameters of this entity.

Methods

This cross-sectional observational study compared parameters belonging to 18 eyes from 9 Spanish patients with Gaucher’s disease Type I with 80 eyes from 40 healthy controls. Complete ophthalmological examination included choroidal and retinal thickness maps with swept source optical coherence tomography. Systemic analysis included genotype, plasmatic biomarkers, [ferritin, chemokine ligand 18 (CCL18) and chitotriosidase (ChT)] and severity scoring systems results [“Gaucher Disease Severity Score Index Type I" (GauSSI-I) and “Gaucher disease severity scoring system” (GD-DS3)].

Results

Nine subjects (18 eyes) were cases (female: 55.5%, mean age 45 years; male: 44.5%, mean age 36 years) and 40 subjects (80 eyes) were controls (female: 49%, mean age 50 years; male: 51%, mean age 55 years). There were no statistically significant differences when comparing ocular parameters (visual acuity; axial length, refractive errors, corneal parameters, lens, retinal and choroidal thickness) between case and control subjects (p>0.05). A statistically significant moderate correlation was observed between lower retinal thickness and choroidal quadrants thickness and greater disease severity scores. A lower central retinal thickness also correlates with higher biological plasmatic levels, and has a statistically significant association with the most affected patient with genotype N370S/Del 55pb. Conversely, higher pachymetry involves a more severe plasmatic concentration of biomarkers.

Conclusions

Our results suggest that pachymetry, and retinal and choroidal thickness, are associated with burden biomarkers and disease severity index scores in Spanish patients with Gaucher’s disease Type I.

Gene expression with corresponding pathways analysis in Gaucher disease

Gaucher disease (GD) caused by mutation in the GBA gene has a wide spectrum of phenotypes. Besides the storage disorder, secondary alteration of various pathways occurs with modification of the expression of many genes. In our work we analysed the expression profile of genes in adult patients with type 1 GD.

METHODS

This study was an observational, cross-sectional analysis of a group of twenty patients with type 1 GD and ten healthy volunteers as a control group. First, on the group of ten persons, microarray gene analysis was performed. Afterwards, significantly regulated genes were selected, and the microarray results were confirmed by real-time PCR on the whole study group.

RESULTS

Based on the microarray results in the pathway analysis, we focused on genes related to chemokines, inflammatory processes, endocytosis, autophagy, and apoptosis. Patients with GD demonstrated up-regulation of genes related to NFkB pathway (NFkB, NKkBR SQSTM1), inflammation (IL-1b), endocytosis and autophagy (BCN1, SMAD), genes coding proteins involved in apoptosis (CASP, NFkB, BCL2) as well as genes related to proteasome degradation (PSMD2, PSMB9) and SNARE complex (SNAP, STX). Simultaneously, we showed down-regulation of genes coding proteins of chemokines and their receptors (GNB4, CCL5). The qRT-PCR results confirmed changes in expression of selected genes. Parallel microarray results showed inhibition of genes related to neurones development and survival (NTRK1) and stimulation of gene expression related to neurodegeneration and apoptosis (BCN1, IL1B).

CONCLUSIONS

The work revealed different pathway activation, especially inflammatory processes followed by autophagy and apoptosis. Our results also pay attention to new pathways leading to disorders of the functioning of the nervous tissue in patients with type 1 GD, which may lead to the development of polyneuropathy and chronic pain. These are clinical symptoms that severely decrease the quality of life in GD patients.

Accumulation of Seminolipid in Sertoli Cells Is Associated with Increased Levels of Reactive Oxygen Species and Male Subfertility: Studies in Aging Arsa Null Male Mice

Seminolipid (also known as sulfogalactosylglycerolipid-SGG), present selectively in male germ cells, plays important roles in spermatogenesis and sperm–egg interaction. The proper degradation of SGG in apoptotic germ cells is also as important. Sertoli cells first phagocytose apoptotic germ cells, then Sertoli lysosomal arylsulfatase A (ARSA) desulfates SGG, the first step of SGG degradation. We have reported that aging male Arsa^−/− mice become subfertile with SGG accumulation in Sertoli cell lysosomes, typical of a lysosomal storage disorder (LSD). Since reactive oxygen species (ROS) levels are increased in other glycolipid-accumulated LSDs, we quantified ROS in Arsa^−/− Sertoli cells. Our analyses indicated increases in superoxide and H₂O₂ in Arsa^−/− Sertoli cells with elevated apoptosis rates, relative to WT counterparts. Excess H₂O₂ from Arsa^−/− Sertoli cells could travel into testicular germ cells (TGCs) to induce ROS production. Our results indeed indicated higher superoxide levels in Arsa^−/− TGCs, compared with WT TGCs. Increased ROS levels in Arsa^−/− Sertoli cells and TGCs likely caused the decrease in spermatogenesis and increased the abnormal sperm population in aging Arsa^−/− mice, including the 50% decrease in sperm SGG with egg binding ability. In summary, our study indicated that increased ROS production was the mechanism through which subfertility manifested following SGG accumulation in Sertoli cells.

Patients with Gaucher disease display systemic oxidative stress dependent on therapy status

Gaucher disease is an autosomal recessive metabolic disorder caused by mutations in GBA1, which encodes for the lysosomal hydrolase enzyme, β-glucocerebrosidase. The resulting misfolded protein can trigger endoplasmic reticulum stress and an unfolded protein response within the affected cells. The enzyme deficiency leads to accumulation of its substrates, glucosylceramide and glucosylsphingosine, within macrophage lysosomes and with prominent disease manifestations in macrophage rich tissues. Resultant lysosomal pathology and impaired autophagy leads to redox imbalance, mitochondrial dysfunction and intracellular oxidative stress. Here we have systematically examined a role for oxidative stress in individuals affected by Gaucher disease. We compared multiple oxidative stress biomarkers in plasma and red blood cell samples from patients who are currently untreated, with those who are stable on standard-of-care therapy, and with healthy controls. We found significant differences in key oxidative stress biomarkers in untreated patients compared to healthy control. In treated patients, results generally fell between the controls and the untreated patients. Interestingly, even asymptomatic and minimally symptomatic untreated patients had evidence of significant systemic oxidative stress. We conclude that underlying oxidative stress may contribute to Gaucher disease pathophysiology including long-term adverse outcomes such as Parkinsonism and malignancies. Therapies targeting oxidative stress may prove useful as adjuvant treatments for Gaucher disease and other lysosomal storage disorders.

Oxidative Stress Parameters, Trace Elements, and Lipid Profile in Iranian Patients with Gaucher Disease

Gaucher disease (GD) is most frequent disorder of glycolipid storage. The glucosylceramide accumulation might lead to oxidative stress and changes in lipid profile. Regarding the main role of trace elements in hematopoiesis and oxidative stress, this study was aimed to evaluate the zinc and copper levels, three oxidative stress parameters, and lipid profile in GD. Thirty-three patients with GD along with 64 age- and sex-matched healthy controls participated in the study. The levels of zinc and copper were determined using atomic absorption/flame emission spectrophotometer. Malondialdehyde level was measured using HPLC. Total antioxidant capacity (TAC), catalase activity, and lipid profile were assessed using colorimetric methods. Data were analyzed using SPSS software version 16.0. Significant decrease in the serum levels of Zn (p < 0.001) and Cu (p < 0.001) was observed in patients with GD compared to controls. Subjects in control group showed significantly higher levels of TAC than patients with GD (p < 0.001). In contrast, plasma concentration of malondialdehyde was insignificantly higher in patients with GD than controls (p = 0.06). There was a direct correlation between TAC and hemoglobin concentration (p = 0.035; r = 0.369) in patients with GD. Furthermore, the calculated area under receiver operating characteristic curve for HDL cholesterol was equal to 0.938. The results showed that both zinc and copper levels decreased in patients with GD. Patients with GD showed decreased serum content of TAC. It was found that improving the deficiency of zinc and copper by supplementing them could be useful in management of patients with GD.

Di (2-ethylhexyl) phthalate induces cardiac disorders in BALB/c mice

Because of the extensive use of phthalates for domestic, medical, and industrial applications, the evaluation of their toxic effects is of major concern to public health. The aim of the present study was to assess the propensity of di (2-ethylhexyl) phthalate (DEHP), one of the most used phthalates, to cause oxidative cardiac damage in mice. DEHP was administered intraperitoneally at doses of 5, 50, and 200 mg/kg body weight for 30 consecutive days in BALB/c mice. We assessed the effect of DEHP on cardiac injury using biochemical profile (such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), creatinine phosphokinase (CPK), total cholesterol (T-CHOL), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)), parameters related to myocardiac oxidative stress, such as malondialdehyde (MDA) level, protein carbonyl (PC) concentration, and DNA fragmentation. In addition, we evaluated antioxidant status; enzymatic (catalase (CAT) and superoxide dismutase (SOD) activities) and non-enzymatic (protein-bound sulfhydryl concentration (PSH)) antioxidants. Acetylcholinesterase (AChE) activity and histopathological changes were also assessed in heart mice treated with DEHP. Our results showed that DEHP induced an elevation of serum marker enzymes and perturbated the lipid profile. In addition, this phthalate increased lipid peroxidation, protein carbonyl levels, and DNA fragmentation in the heart in a dose-dependent manner. Antioxidant status was also perturbated by the increase of the CAT and SOD activities and the decrease of the protein-bound sulfhydryl concentration. AChE activity was also inhibited in the heart following the treatment with DEHP. These biochemical alterations were also confirmed by histopathological changes. Increased free radical production at various doses of DEHP would result in impairment of the redox status leading to an enhanced dose-dependent cardiotoxicity.

Redox regulation of autophagy in skeletal muscle

Autophagy is a cellular degradative pathway that involves the delivery of cytoplasmic components, including proteins and organelles, to the lysosome for degradation. Autophagy is implicated in the maintenance of skeletal muscle; increased autophagy leads to muscle atrophy while decreased autophagy leads to degeneration and weakness. A growing body of work suggests that reactive oxygen species (ROS) are important cellular signal transducers controlling autophagy. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases and mitochondria are major sources of ROS generation in skeletal muscle that are likely regulating autophagy through different signaling cascades based on localization of the ROS signals. This review aims to provide insight into the redox control of autophagy in skeletal muscle. Understanding the mechanisms by which ROS regulate autophagy will provide novel therapeutic targets for skeletal muscle diseases.