Delta-ALA-D activity is a reliable marker for oxidative stress in bone marrow transplant patients

Serum Levels of miR-122-5p and miR-125a-5p Predict Hepatotoxicity Occurrence in Patients Undergoing Autologous Hematopoietic Stem Cell Transplantation

Hepatic complications are an acknowledged cause of mortality and morbidity among patients undergoing hematopoietic stem cell transplantation. In this study, we aimed to evaluate the potential role in the prediction of liver injury of five selected microRNAs (miRNAs)-miR-122-5p, miR-122-3p, miR-15b-5p, miR-99b-5p, and miR-125a-5p-in the setting of autologous hematopoietic stem cell transplantation (ASCT). A total of 66 patients were included in the study: 50 patients (75.8%) with multiple myeloma (MM) and 16 (24.2%) with lymphoma. Blood samples were collected after the administration of the conditioning regimen, on the day of transplant (day 0). The expression levels of selected miRNAs were quantified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) using the miRCURY LNA miRNA Custom PCR Panels (QIAGEN). In a multivariate logistic regression analysis adjusted for age, sex, and the administered conditioning regimen, two miRNAs, hsa-miR-122-5p (odds ratio, OR 2.10, 95% confidence interval, CI: 1.29-3.42, p = 0.0029) and hsa-miR-125a-5p (OR 0.27, 95% CI: 0.11-0.71, p = 0.0079), were independent for hepatic toxicity occurrence during the 14 days after transplant. Our model in 10-fold cross-validation preserved its diagnostic potential with a receiver operating characteristics area under the curve (ROC AUC) of 0.75, 95% CI: 0.63-0.88 and at optimal cut-off reached 72.0% sensitivity and 74.4% specificity. An elevated serum level of miR-122-5p and decreased level of miR-125a-5p on day 0 are independent risk factors for hepatotoxicity in ASCT recipients, showing promise in accurately predicting post-ASCT complications. Identifying patients susceptible to complications has the potential to reduce procedure costs and optimize the selection of inpatient or outpatient procedures.

Pre-Ride Biomarkers and Endurance Horse Welfare: Analyzing the Impact of the Elimination of Superoxide Dismutase, δ-Aminolevulinic-Dehydratase, Thiobarbituric Acid Reactive Substances, Iron, and Serum Amyloid A Levels in Elite 160 km Endurance Rides

High elimination rates and concerns for horse welfare are important issues in endurance riding. Improved understanding of the causes of elimination could increase completion rates in this sport. We have identified pre-ride laboratory risk factors that enable an assessment of potential elimination before the ride. A longitudinal cohort study was performed among 49 healthy horses competing in the 160 km endurance ride at the 2016 World Championship of Endurance Riding in Samorin/Slovakia. Blood samples were taken before the event. For statistical evaluation, horses were categorized into three groups: finishers, lame horses, and metabolically eliminated horses. Risk factors were calculated for each group using multinominal logistic regression. δ-Aminolevulinic-dehydratase (ALAD), thiobarbituric acid reactive substances (TBARSs), iron, and serum amyloid A (SAA) were measured and did not show an impact on the race outcome, but elevated pre-ride superoxide dismutase (SOD) was shown to have an effect on lameness elimination (p = 0.011). It might serve as an indicator for withdrawing horses at risk of later elimination before endurance rides, ultimately resulting in lower elimination rates and an increase in overall horse welfare.

Oxidative profile, inflammatory responses and δ-aminolevulinate dehydratase enzyme activity in influenza B virus infection

The aim of the current study was to determine the activity of the delta-aminolevulinate dehydratase (δ-ALA-D) enzyme, oxidative stress biomarkers and the expression of cytokines in those infected with influenza B virus (IBV). To evaluate the activity of the δ-ALA-D enzyme, lipid peroxidation was estimated as levels of thiobarbituric acid reactive substances, protein and non-protein thiol groups, ferric-reducing antioxidant power (FRAP), vitamin C concentration and cytokine levels in IBV-infected individuals (n  = 50) and a control group (n = 30). δ-ALA-D activity was significantly lower in IBV-infected individuals compared with controls, as well as levels of thiols, vitamin C and FRAP. Lipid peroxidation and cytokine levels of IL-6, IL-10, IL-17A and IFN-y were statistically higher in the IBV group. In conclusion, we found evidence of the generation of oxidants, the depletion of the antioxidant system, decrease in the activity of the δ-ALA-D enzyme and an increase in the synthesis of cytokines, thus contributing to a better understanding of oxidative and inflammatory pathways during IBV infection.

In vivo assessment of dichlorvos induced histological and biochemical impairments coupled with expression of p53 responsive apoptotic genes in the liver and kidney of fish, Channa punctatus (Bloch, 1793)

Sub-lethal exposure of dichlorvos induces oxidative stress, consequent genetic instability and apoptosis coupled with impairments in biochemical, histopathological and transcription of genes in Channa punctatus. Exposure of 5% (0.041 mg/L; E2) and 10% (0.082 mg/L; E3) of 96 h-LC₅₀ of dichlorvos significantly (p < 0.05) elevated the reactive oxygen species (ROS) generation and activities of SOD and CAT, as compared to control (E1) after 30 d. The maximum reduction in reduced glutathione (GSH) was recorded in the liver (18.53 ± 0.81 μg/mg of protein) and kidney (19.32 ± 0.97 μg/mg of protein); while the total protein contents were also found reduced, 278.38 ± 8.40 μg/mL (liver) and 248.44 ± 7.28 μg/mL (kidney), after 30 days in E3, in comparison to respective controls. Further, significant (p < 0.05) induction in micronuclei (MN) and apoptotic cells (AC), in a dose- and exposure-based manner were also recorded. Moreover, a significant (p < 0.05) up-regulation of p53 (2.51-fold in liver), bax (2.03-fold in liver; 1.99-fold in kidney) and casp3a (2.26-fold in liver; 2.10-fold in kidney) together with an elevated expression of cat (1.73-fold in liver; 1.12-fold in kidney), p53 (1.27-fold in kidney) and apaf-1 (1.72-fold in liver) in fish exposed to higher dose of dichlorvos for 30 d evidently reflects geno-toxicological potential of referenced pesticide. Disturbed biochemical and molecular parameters evince that the fish experienced oxidative stress as is further supported by prominent pathological observations in liver and kidney. Findings are, thus, helpful in organ-specific molecular scanning against aquatic toxicants like dichlorvos.

Evaluation of oxidative stress and δ-aminolevulinate dehydratase activity in twin pregnancies

Purpose: To assess and understand the maternal oxidative stress in twin pregnancies, currently not studied, through ascertain indicators of oxidative damage in maternal blood in response of two fetuses, as well as the relation of placenta with or without the increase of oxidative stress in these gestations.Materials and methods: The activity of delta-aminolevulinate dehydratase (δ-ALA-D) was analyzed as an indirect marker of oxidative stress, as well as the quantification of thiobarbituric acid reactive substances (TBARS), protein thiol groups (P-SH) and nonprotein thiol groups (NP-SH), vitamin C (VIT C) and catalase activity (CAT) in maternal blood samples from twin (n = 30) and single (n = 30) pregnancies. This study was approved by the Human Ethics Committee UFSM (register by the number 49823015.4.0000.5346).Results: TBARS was significantly higher in twin pregnancies, while thiol groups, VIT C and CAT were decreased, asides from the reduced activity of δ-ALA-D in comparison to single fetus gestations.Conclusions: The study established an oxidative stress increased and an antioxidant ability decreased in twin pregnancies, suggesting a possible relation between the levels of oxidants and antioxidants with the complications in those gestations.

Temporal expression profiling of plasma proteins reveals oxidative stress in early stages of Type 1 Diabetes progression

Blood markers other than islet autoantibodies are greatly needed to indicate the pancreatic beta cell destruction process as early as possible, and more accurately reflect the progression of Type 1 Diabetes Mellitus (T1D). To this end, a longitudinal proteomic profiling of human plasma using TMT-10plex-based LC-MS/MS analysis was performed to track temporal proteomic changes of T1D patients (n=11) across 9 serial time points, spanning the period of T1D natural progression, in comparison with those of the matching healthy controls (n=10). To our knowledge, the current study represents the largest (>2000 proteins measured) longitudinal expression profiles of human plasma proteome in T1D research. By applying statistical trend analysis on the temporal expression patterns between T1D and controls, and Benjamini-Hochberg procedure for multiple-testing correction, 13 protein groups were regarded as having statistically significant differences during the entire follow-up period. Moreover, 16 protein groups, which play pivotal roles in response to oxidative stress, have consistently abnormal expression trend before seroconversion to islet autoimmunity. Importantly, the expression trends of two key reactive oxygen species-decomposing enzymes, Catalase and Superoxide dismutase were verified independently by ELISA.

BIOLOGICAL SIGNIFICANCE

The temporal changes of >2000 plasma proteins (at least quantified in two subjects), spanning the entire period of T1D natural progression were provided to the research community. Oxidative stress related proteins have consistently different dysregulated patterns in T1D group than in age-sex matched healthy controls, even prior to appearance of islet autoantibodies - the earliest sign of islet autoimmunity and pancreatic beta cell stress.

Association between Blood Lead Levels and Delta-Aminolevulinic Acid Dehydratase in Pregnant Women

Blood lead levels (BLLs) and delta-aminolevulinic acid dehydratase (ALAD) activity are considered biomarkers of lead exposure and lead toxicity, respectively. The present study was designed to investigate the association between BLLs and ALAD activity in pregnant women from Durango, Mexico. A total of 633 pregnant women aged 13–43 years participated in this study. Blood lead was measured by a graphite furnace atomic absorption spectrometer. ALAD activity was measured spectrophotometrically. Mean blood lead was 2.09 ± 2.34 µg/dL; and 26 women (4.1%) crossed the Centers for Disease Control (CDC) recommended level of 5 µg/dL. ALAD activity was significantly lower in women with levels of lead ≥5 µg/dL compared to those with BLLs < 5 µg/dL (p = 0.002). To reduce the influence of extreme values on the statistical analysis, BLLs were analyzed by quartiles. A significant negative correlation between blood lead and ALAD activity was observed in the fourth quartile of BLLs (r = −0.113; p < 0.01). Among women with blood lead concentrations ≥2.2 µg/dL ALAD activity was negatively correlated with BLLs (r = −0.413; p < 0.01). Multiple linear regression demonstrated that inhibition of ALAD in pregnant women may occur at levels of lead in blood above 2.2 µg/dL.

Liver δ-aminolevulinate dehydratase activity is inhibited by neonicotinoids and restored by antioxidant agents

Neonicotinoids represent the most used class of insecticides worldwide, and their precursor, imidacloprid, is the most widely marketed. The aim of this study was to evaluate the effect of imidacloprid on the activity of hepatic δ-aminolevulinate dehydratase (δ-ALA-D), protective effect of potential antioxidants against this potential effect and presence of chemical elements in the constitution of this pesticide. We observed that δ-ALA-D activity was significantly inhibited by imidacloprid at all concentrations tested in a dose-dependent manner. The IC₅₀ value was obtained and used to evaluate the restoration of the enzymatic activity. δ-ALA-D inhibition was completely restored by addition of dithiotreitol (DTT) and partly by ZnCl_2, demonstrating that the inhibition occurs by oxidation of thiol groups and by displacement of the Zn (II), which can be explained by the presence of chemical elements found in the constitution of pesticides. Reduced glutathione (GSH) had the best antioxidant effect against to δ-ALA-D inhibition caused by imidacloprid, followed by curcumin and resveratrol. It is well known that inhibition of the enzyme δ-ALA-D may result in accumulation of its neurotoxic substrate (δ-ALA), in this line, our results suggest that further studies are needed to investigate the possible neurotoxicity induced by neonicotinoids and the involvement of antioxidants in cases of poisoning by neonicotinoids.

Rapamycin increases oxidative stress response gene expression in adult stem cells

Balancing quiescence with proliferation is of paramount importance for adult stem cells in order to avoid hyperproliferation and cell depletion. In some models, stem cell exhaustion may be reversed with the drug rapamycin, which was shown can suppress cellular senescence in vitro and extend lifespan in animals. We hypothesized that rapamycin increases the expression of oxidative stress response genes in adult stem cells, and that these gene activities diminish with age. To test our hypothesis, we exposed mice to rapamycin and then examined the transcriptome of their spermatogonial stem cells (SSCs). Gene expression microarray analysis revealed that numerous oxidative stress response genes were upregulated upon rapamycin treatment, including superoxide dismutase 1, glutathione reductase, and delta-aminolevulinate dehydratase. When we examined the expression of these genes in 55-week-old wild type SSCs, their levels were significantly reduced compared to 3-week-old SSCs, suggesting that their downregulation is coincident with the aging process in adult stem cells. We conclude that rapamycin-induced stimulation of oxidative stress response genes may promote cellular longevity in SSCs, while a decline in gene expression in aged stem cells could reflect the SSCs' diminished potential to alleviate oxidative stress, a hallmark of aging.

Effects of diphenyl diselenide on oxidative stress induced by sepsis in rats

Sepsis is a potentially deadly complication that can be caused by different factors. Actually, it is known that oxidative stress is involved in the pathogenesis of sepsis. Thus, the aim of this study was to evaluate the effect of diphenyl diselenide (PhSe)(2), an emergent compound, on oxidative stress parameters induced by sepsis in rats. Animals were pre-injected with (PhSe)(2) or vehicle. Twenty-four hours later, sepsis was induced by cecal ligation puncture (CLP). After 12 h, liver was taken for thiobarbituric acid reactive species (TBARS) measurement, δ-aminolevunic acid dehydratase (δ-ALA-D), Cu/Zn superoxide dismutase (Cu/Zn SOD) and catalase (CAT) activities assay. The sepsis increased TBARS, inhibited δ-ALA-D, activated Cu/Zn SOD and had a tendency to decrease CAT activity. However, (PhSe)(2) prevented the TBARS formation, but did not prevent the inhibition of δ-ALA-D activity in the animals with damage. Thus, this study showed that (PhSe)(2) partially prevents the oxidative stress induced by sepsis, indicating the potential of this compound as a treatment for this pathology. Nevertheless, more tests should be performed to confirm the hypothesis suggested here.

Molecular docking studies of disubstituted diaryl diselenides as mammalian δ-aminolevulinic acid dehydratase enzyme inhibitors

δ-Aminolevulinic acid dehydratase (δ-ALAD) is a metalloprotein that catalyzes porphobilinogen formation. This enzyme is sensitive to pro-oxidants and classically used as a biomarker of lead (Pb) intoxication. Diphenyl diselenide [(PhSe)₂] and analogs bis(4-chlorophenyl) diselenide [(pCl₃PhSe)₂], bis(4-methoxyphenyl)diselenide [(pCH₃OPhSe)₂], and bis[3-(trifluoromethy)phenyl] diselenide [(mCF₃PhSe)₂] inhibit mammalian δ-ALAD by oxidizing enzyme cysteinyl residues, which are involved in diselenide-induced toxicity. 2-Cysteinyl residues from δ-ALAD are believed to sequentially interact with (PhSe)₂. Thus this study utilized protein-ligand docking analyses to determine which cysteinyl residues might be involved in the inhibitory effect of (PhSe)₂ and analogs toward δ-ALAD. All diselenides that interact in a similar manner with the active site of δ-ALAD were examined. Docking simulations indicated an important role for π-π interactions involving Phe208 and cation-π interactions involving Lys199 and Arg209 residues with the aromatic ring of (PhSe)₂ and analogs. Based upon these interactions an approximation between Se atoms and -SH of Cys124, with distances ranging between 3.3 Å and 3.5 Å, was obtained. These data support our previous postulations regarding the mechanism underlying δ-ALAD oxidation mediated by (PhSe)₂ and analogs. Based on protein-ligand docking analyses, data indicated that -SH of Cys124 attacks one of the Se atoms of -SH of (PhSe)₂ releasing one PhSeH (selenophenol). Subsequently, the -SH of Cys132 attacks the sulfur atom of Cys124 (from the bond of E-S-Se-Ph indermediate), generating the second PhSe⁻, and the oxidized and inhibited δ-ALAD. In conclusion, AutoDock Vina 1.1.1 was a useful tool to search for diselenides inhibitors of δ-ALAD, and, most importantly, it provided insight into molecular mechanisms involved in enzyme inhibition.