Glucose-6-phosphate Dehydrogenase Activity Research Articles

Göynük Çayı'nda (Bingöl) yakalanan Cyprinion macrostomus dokularında antioksidan savunma sistemi göstergelerindeki mevsimsel değişiklikler

In this study, antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase GPx), glutathione reductase (GR) and glucose 6-phosphate dehydrogenase (G6PD)) and malondialdehyde (MDA) levels occurring throughout the year were examined in Cyprinion macrostomus tissues (kidney, gill, liver and gonad) captured from Göynük Stream (Bingöl, Turkey). For this purpose, two locations (Ilıcalar and Garip) where fish can be caught regularly in summer, autumn, winter and spring were determined. Fish were caught regularly from these two locations every month and brought to the laboratory. Spectrophotometric methods were used to determine enzyme activities and MDA levels in the study. As a result of the study, it was determined that the MDA level and enzyme activities between Ilıcalar and Garip stations, in general, were statistically different from each other in all tissues. However, it was observed that there were important differences in general between the seasons at both stations. In addition, while GR and G6PD activities were lower than other enzyme activities throughout the study, CAT and SOD activities were higher.

Comparison of growth, and non-specific immune of crisp and ordinary tilapia (Oreochromis niloticus)

Tilapia (Oreochromis niloticus) is a kind of worldwide farmed fish that is commercially cultured in more than a hundred nations. The tilapia dietary faba bean (Vicia faba L.) for 90– 120 d improves muscle quality such as higher muscle hardness and crispiness. However, faba bean contain a wide variety of antinutritional factors such as phenolics, tannins, trypsin inhibitor activity, and phytic acid. Antinutritional factors through themselves or their metabolic products affect the health of fish. This study was compared growth, antioxidant activity, carbon metabolic enzyme activity and immune-related gene expression profiles between the ordinary and crisp tilapia. The results indicated that crisp tilapia (888.00 ± 200.83 g) had a significantly lower body weight compared with ordinary tilapia (1078.67 ± 162.56 g) (P < 0.05). There were no significant differences in superoxide dismutase (SOD) and antioxidant capacity (T-AOC) between crisp and ordinary tilapia in both serum and liver. The crisp tilapia recorded significantly lower acid phosphatase (ACP), and alkaline phosphatase (AKP) in contrast to the ordinary tilapia in serum (P < 0.05), but not significant in liver. The crisp tilapia (serum: 8.05 ± 1.23 U/mL, liver: 7.59 ± 1.09 U/mL) exposure could significantly inhibit glucose 6-phosphate dehydrogenase (G6PD) activities compared with ordinary tilapia (serum: 5.07 ± 0.91 U/mL, liver: 4.10 ± 1.18 U/mL) (P < 0.05). The lysozyme (LZM) and triglyceride (TG) of ordinary and crisp tilapia were similar. The heat shock protein70 (Hsp70) and tumor necrosis factor-α (TNF-α) expression of crisp tilapia demonstrated significant upregulation when compared with ordinary tilapia in the haemocytes and liver, whereas the interleukin-1β (IL-1β), metallothionein (MT), and chemokine C-C-Motif Ligand 3 (CCL) expression of crisp tilapia were significantly deregulated in the liver. In conclusion, the crisp tilapia can decrease growth, ACP, AKP, and G6PDH activity, whereas Hsp70 and TNF-α expression of crisps demonstrated significant upregulation. The results would contribute to comprehend the physiological parameters during tilapia crisping process and exploring the mechanism of tilapia brittleness.

Glucose 6 phosphate dehydrogenase deficiency quantitative test in dried blood spot- a potential marker for adult unknown G6PD deficiency.

Glucose 6 Phosphate Dehydrogenase (G6PD) enzyme activity estimation in a freshly collected blood sample is the most widely used diagnostic method for the diagnosis of G6PD deficiency. The objective is to evaluate the need for newborn screening for G6PD deficiency over post-malarial diagnosis and the feasibility and reliability of using dried blood spots (DBS) as samples for screening. A total of 562 samples were analyzed for G6PD and parallel measurement of G6PD activity by the colorimetric method in whole blood and DBS was carried out in the neonatal subset. Among 466 adults, 27 (5.7%) showed G6PD deficiency, out of whom 22 (81.48%) were diagnosed after the malarial encounter. In the pediatric group, 8 neonates showed G6PD deficiency. G6PD activity estimated from DBS samples agreed with whole blood, with a statistically significant strong positive correlation. Screening of G6PD deficiency at birth to prevent future unwarranted complications, using DBS is feasible.

Glucocorticoids decrease thermogenic capacity and increase triacylglycerol synthesis by glycerokinase activation in the brown adipose tissue of rats.

Although it is well established that glucocorticoids inactivate thermogenesis and promote lipid accumulation in interscapular brown adipose tissue (IBAT), the underlying mechanisms remain unknown. We found that dexamethasone treatment (1 mg/kg) for 7 days in rats decreased the IBAT thermogenic activity, evidenced by its lower responsiveness to noradrenaline injection associated with reduced content of mitochondrial proteins, respiratory chain protein complexes, noradrenaline, and the β3 -adrenergic receptor. In parallel, to understand better how dexamethasone increases IBAT lipid content, we also investigated the activity of the ATP citrate lyase (ACL), a key enzyme of de novo fatty acid synthesis, glucose-6-phosphate dehydrogenase (G6PD), a rate-limiting enzyme of the pentose phosphate pathway, and the three glycerol-3-P generating pathways: (1) glycolysis, estimated by 2-deoxyglucose uptake, (2) glyceroneogenesis, evaluated by phosphoenolpyruvate carboxykinase activity and pyruvate incorporation into triacylglycerol-glycerol, and (3) direct phosphorylation of glycerol, investigated by the content and activity of glycerokinase. Dexamethasone increased the mass and the lipid content of IBAT as well as plasma levels of glucose, insulin, non-esterified fatty acid, and glycerol. Furthermore, dexamethasone increased ACL and G6PD activities (79% and 48%, respectively). Despite promoting a decrease in the incorporation of U-[14 C]-glycerol into triacylglycerol (~54%), dexamethasone increased the content (~55%) and activity (~41%) of glycerokinase without affecting glucose uptake or glyceroneogenesis. Our data suggest that glucocorticoid administration reduces IBAT thermogenesis through sympathetic inactivation and stimulates glycerokinase activity and content, contributing to increased generation of glycerol-3-P, which is mostly used to esterify fatty acid and increase triacylglycerol content promoting IBAT whitening.

Comparison of various RBC indices and Glucose 6 phosphate dehydrogenase activity in patients with and without malaria

Introduction and Aim: Malaria is endemic in many parts of India. Glucose 6 phosphate dehydrogenase (G6PD) deficiency is known to protect against malaria. G6PD deficient individuals afflicted with malaria when treated with primaquine, the first line oxidant drug of malaria, encounter adverse to fatal complications due to acute precipitation of hemolytic anemia. There is a need to assess RBC indices in malaria, its implications in G6PD deficiency, and its acute manifestations. The aim of this study was to compare and correlate various RBC indices and G6PD activity in patients with and without malaria and to find a prevalence of G6PD deficiency in a tertiary care hospital. Materials and Methods: The present study was carried out by the Biochemistry Department of Kasturba Medical College, Manipal in 363 participants (with malaria and without malaria). Mann Whitney U test and Spearman’s Rank correlation were employed to assess group differences and correlation, respectively. Results: 218 cases of malaria in 365 days from a tertiary care hospital in South India is an alarming incidence and annuls the fact that the malaria prevalence is relatively low in South India. Complete blood counts and red blood indices did not show any statistically significant difference between the study groups. No statistically significant correlation was found between G6PD activity and RBC indices in the present study. Conclusion: No significant differences between hematological indicators and malaria with or without G6PD deficiency hint towards the necessity of G6PD tests for radical treatment of malaria as hematological indices are unable to predict the defective enzyme activity.

Role of amino acid oxidation and protein unfolding in peroxyl radical and peroxynitrite-induced inactivation of glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides.

The mechanisms underlying the inactivation of Leuconostoc mesenteroides glucose 6-phosphate dehydrogenase (G6PDH) induced by peroxyl radicals (ROO●) and peroxynitrite (ONOO-), were explored. G6PDH was incubated with AAPH (2,2' -azobis(2-methylpropionamidine)dihydrochloride), used as ROO● source, and ONOO-. Enzymatic activity was assessed by NADPH generation, while oxidative modifications were analyzed by gel electrophoresis and liquid chromatography (LC) with fluorescence and mass detection. Changes in protein conformation were studied by circular dichroism (CD) and binding of the fluorescent dye ANS (1-anilinonaphthalene-8-sulfonic acid). Incubation of G6PDH (54.4μM) with 60mM AAPH showed an initial phase without significant changes in enzymatic activity, followed by a secondary time-dependent continuous decrease in activity to ∼59% of the initial level after 90min. ONOO- induced a significant and concentration-dependent loss of G6PDH activity with ∼46% of the initial activity lost on treatment with 1.5mM ONOO-. CD and ANS fluorescence indicated changes in G6PDH secondary structure with exposure of hydrophobic sites on exposure to ROO●, but not ONOO-. LC-MS analysis provided evidence for ONOO--mediated oxidation of Tyr, Met and Trp residues, with damage to critical Met and Tyr residues underlying enzyme inactivation, but without effects on the native (dimeric) state of the protein. In contrast, studies using chloramine T, a specific oxidant of Met, provided evidence that oxidation of specific Met and Trp residues and concomitant protein unfolding, loss of dimer structure and protein aggregation are involved in G6PDH inactivation by ROO●. These two oxidant systems therefore have markedly different effects on G6PDH structure and activity.

Hepatic and blood alterations in Lithobates catesbeianus tadpoles exposed to sulfamethoxazole and oxytetracycline

In this study the effects of environmentally realistic concentrations of the antibiotics sulfamethoxazole (SMX) and oxytetracyclyne (OTC) on Lithobates catesbeianus tadpoles were evaluated, through the analyzes of the frequencies of micronucleus and nuclear abnormalities in erythrocytes, alterations in leucocytes, liver histopathology, and changes in hepatic esterase activities and oxidative stress biomarkers. The animals were exposed for 16 days at concentrations of 0 (control), 20, 90 and 460 ng L−1. No significant difference was found in the frequencies of micronucleus and nuclear abnormalities. The two highest concentrations of SMX and all concentrations of OTC caused a significant increase in the number of lymphocytes. A significant decrease in the number of neutrophils compared to the control group was observed for all concentrations tested of both antibiotics. Also, decrease in the activity of glutathione S-transferase and high histopathological severity scores, indicating liver damage, were found in tadpoles exposed to the two highest concentrations of SMX and all concentrations of OTC. The main changes in the liver histopathology were the presence of inflammatory infiltrate, melanomacrophages, vascular congestion, blood cells and eosinophils. Esterase activities were unchanged. Indeed, the two highest concentrations of OTC caused a reduction in the activities of superoxide dismutase and glucose 6-phosphate dehydrogenase, while the highest concentration inhibited the activity of glutathione peroxidase and increased protein carbonyl levels. These results evidences that environmentally realistic concentrations of SMX and OTC in aquatic environments are capable to significantly disrupt tadpoles’ physiology, possibly affecting negatively their survival rate in natural environments.

Screening of in vitro and in silico effect of Fluorophenylthiourea compounds on glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase enzymes.

Inhibition studies of enzymes in the pentose phosphate pathway (PPP) have recently emerged as a promising technique for pharmacological intervention in several illnesses. Glucose 6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) are the most important enzymes of the PPP. For this purpose, in the current study, we examined the effect of some fluorophenylthiourea on G6PD and 6PGD enzyme activity. These compounds exhibited moderate inhibitory activity against G6PD and 6PGD with KI values ranging from 21.60 ± 8.42 to 39.70 ± 11.26 μM, and 15.82 ± 1.54 to 29.97 ± 5.72 μM, respectively. 2,6-difluorophenylthiourea displayed the most potent inhibitory effect for G6PD, and 2-fluorophenylthiourea demonstrated the most substantial inhibitory effect for 6PGD. Furthermore, the molecular docking analyses of the fluorophenylthioureas, competitive inhibitors, were performed to understand the binding interactions at the enzymes' binding site.

The metabolic and toxic acute effects of phloretin in the rat liver

The current study sought to evaluate the acute effects of phloretin (PH) on metabolic pathways involved in the maintenance of glycemia, specifically gluconeogenesis and glycogenolysis, in the perfused rat liver. The acute effects of PH on energy metabolism and toxicity parameters in isolated hepatocytes and mitochondria, as well as its effects on the activity of a few key enzymes, were also evaluated. PH inhibited gluconeogenesis from different substrates, stimulated glycogenolysis and glycolysis, and altered oxygen consumption. The citric acid cycle activity was inhibited by PH under gluconeogenic conditions. Similarly, PH reduced the cellular ATP/ADP and ATP/AMP ratios under gluconeogenic and glycogenolytic conditions. In isolated mitochondria, PH inhibited the electron transport chain and the FoF1–ATP synthase complex as well as acted as an uncoupler of oxidative phosphorylation, inhibiting the synthesis of ATP. PH also decreased the activities of malate dehydrogenase, glutamate dehydrogenase, glucose 6-phosphatase, and glucose 6-phosphate dehydrogenase. Part of the bioenergetic effects observed in isolated mitochondria was shown in isolated hepatocytes, in which PH inhibited mitochondrial respiration and decreased ATP levels. An aggravating aspect might be the finding that PH promotes the net oxidation of NADH, which contradicts the conventional belief that the compound operates as an antioxidant. Although trypan blue hepatocyte viability tests revealed substantial losses in cell viability over 120 min of incubation, PH did not promote extensive enzyme leakage from injured cells. In line with this effect, only after a lengthy period of infusion did PH considerably stimulate the release of enzymes into the effluent perfusate of livers. In conclusion, the increased glucose release caused by enhanced glycogenolysis, along with suppression of gluconeogenesis, is the opposite of what is predicted for antihyperglycemic agents. These effects were caused in part by disruption of mitochondrial bioenergetics, a result that should be considered when using PH for therapeutic purposes, particularly over long periods and in large doses.

MTORC1 activation induced proximal tubular damage via the pentose phosphate pathway in lupus nephritis

More recent studies suggested that metabolic disorders could contribute to the pathogenesis of systemic lupus erythematosus (SLE) and lupus nephritis (LN). The present work aimed at identifying metabolic reprogramming in the kidney of lupus nephritis via proteomics and investigating the potential regulatory mechanism. The proteomic studies on the renal biopsies revealed that the pentose phosphate pathway (PPP) was significantly enriched in the kidneys of LN patients compared with normal controls (NCs). Immunohistochemical stanning of glucose-6-phosphate dehydrogenase (G6PD), the key rate-limiting enzyme of PPP, verify the results of proteomics. We found that G6PD was highly expressed in the kidneys of LN patients and correlated with several clinicopathological indices. The univariate Cox regression analysis (HR, 95%CI, 1.877 (1.059–3.328), P = 0.031) and Kaplan-Meier (KM) analysis (P = 0.028) suggested that high G6PD expression in the tubulointerstitial area was a risk factor for worse prognosis. Moreover, the Gene set enrichment analysis (GSEA) demonstrated that the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway ranked first in the kidneys of LN patients with high G6PD expression and G6PD was co-localized with mTORC1 activation in the tubule. Immunoglobulin G (IgG) isolated from LN patients significantly activated the mTORC1 pathway and increased G6PD expression, G6PD activity, NADPH production, NADPH oxidase 2 (NOX2) expression, reactive oxygen species (ROS) production, and cell apoptosis in tubule cells in vitro. The above phenotypes were partially rescued after the addition of rapamycin or knock-down of G6PD. Overall, our study suggested that renal G6PD expression was associated with the overall enhanced disease activity and worse renal prognosis. mTORC1 activation might be involved in IgG-LN-induced tubular damage via PPP.

Maternal exposure to genistein during pregnancy and oxidative DNA damage in testes of male mouse offspring.

BackgroundGenistein is a dietary supplement with phyto-estrogenic properties. Therefore, high intake of genistein during pregnancy may have adverse effects on the genetic integrity of testes and germ cells of male offspring. In this study, we examined whether maternal exposure to genistein during pregnancy induced oxidative DNA damage in the male germline at adolescence.MethodsAtm-ΔSRI mice have lower glucose-6-phosphate dehydrogenase (G6PDH) activity, which is important for maintaining levels of reduced glutathione and therefore these mice have an increased susceptibility to oxidative stress. Parental heterozygous Atm-ΔSRI mice received a genistein-rich or control diet, after which they were mated to obtain offspring. During pregnancy, mothers remained on the respective diets and after delivery all animals received control diets. Redox status and oxidative DNA damage were assessed in testes and sperm of 12 weeks old male offspring. Gene expression of Cyp1b1, Comt, and Nqo1 was assessed in testes, and DNA methylation as possible mechanism for transmission of effects to later life.ResultsIntake of genistein during pregnancy increased oxidative DNA damage in testes of offspring, especially in heterozygous Atm-ΔSRI mice. These increased DNA damage levels coincided with decreased expression of Comt and Nqo1. Heterozygous Atm-ΔSRI mice had higher levels of DNA strand breaks in sperm compared to wild type littermates, and DNA damage was further enhanced by a genistein-rich maternal diet. G6PDH activity was higher in mice with high maternal intake of genistein compared to control diets, suggesting compensation against oxidative stress. A positive correlation was observed between the levels of DNA methylation and oxidative DNA damage in testes.ConclusionThese data indicate that prenatal exposure to genistein altered gene expression and increased DNA damage in testes and sperm of adolescent male offspring. These effects of genistein on DNA damage in later life coincided with alterations in DNA methylation.

Cut-off values for diagnosis of G6PD deficiency by flow cytometry in Thai population

In heterozygous females, X-inactivation causes a change in glucose-6-phosphate dehydrogenase (G6PD) activity from normal to deficient. Most G6PD screening tests are used to accurately diagnose hemizygous males, but they are less reliable for diagnosing heterozygous females. This study established flow cytometric cut-off values for screening of G6PD deficiency in hemizygous males and heterozygous or homozygous females. We studied 205 (125 females, 80 males) leftover blood samples from quantitative methemoglobin reduction (MR) screening. G6PD gene mutations determined by multiplex amplification refractory mutation system-polymerase chain reaction and direct DNA sequencing were used as the gold standard reference. Accuracy of the test, including the sensitivity, specificity, and positive and negative predictive values, was analyzed using MedCalc software. The optimal cut-off values for classification of %red blood cells with normal G6PD activity or %bright cells into homozygous normal, heterozygous, and homozygous deficiency in females were 85.4–100%, 6.3–85.3%, and 0–6.2%, respectively (sensitivity 93.2%, specificity 100%). The cut-offs for classification into hemizygous normal and hemizygous deficiency in males were 76.5–100% and 0–76.4%, respectively (sensitivity 100%, specificity 96.5%). Flow cytometry can be used to differentiate heterozygous females with intermediate phenotype from homozygous females, but cannot distinguish between heterozygous females with extreme phenotype and homozygous females. By flow cytometry, heterozygous and homozygous deficiency was detected in 29.6% and 3.2% of females, respectively. Among males, hemizygous deficiency was found in 31.3%. Flow cytometry can be used to screen patients with G6PD deficiency, and reliably and efficiently identify heterozygous and homozygous females, and hemizygous males based on cellular G6PD activity.

Prevalence of Glucose-6-phosphate Dehydrogenase (G6PD) Deficiency in Jiroft City in Southern Iran

Background and Aims: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a global problem and the most common cause of jaundice in neonates. Hence, this study was conducted to investigate the prevalence of G6PD deficiency in Jiroft city in southern Kerman.&#x0D; Materials and Methods: This descriptive cross-sectional study was carried out from 2016 to 2019. Blood samples were taken from all patients referred to Imam Hospital in Jiroft city in southern Iran. The G6PD enzyme activity was evaluated by a fluorescent spot test.&#x0D; Results and Conclusions: In the present study, a total of 7791 newborns were included. Abnormal activity of G6PD was seen in 779 (10%) subjects. Out of 779 patients, 728 (9.4%) were found to be G6PD deficient, and 49 (0.6%) exhibited partial deficiency. A relatively high percentage of G6PD deficiency was seen in newborns of Jirof city. We strongly recommend screening for G6PD enzyme activity in all newborns in this city.

Molecular Characterization and Genotype-Phenotype Correlation of G6PD Mutations in Five Ethnicities of Northern Vietnam.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme disorder and is caused by G6PD gene mutations. To date, more than 400 variants in the G6PD gene have been discovered, and about 160 identified variants are associated with a significant decrease in the G6PD enzyme activity. However, the molecular characterization and epidemiological study of G6PD deficiency are still limited in Vietnam. Therefore, we conducted this study to determine the G6PD variants among the Vietnamese populations and evaluate their correlation to G6PD enzyme activity. A total of 339 patients (302 males and 37 females) were enrolled in this study. The G6PD variants were identified by Sanger sequencing. Our results indicate that males are more severely deficient in G6PD than females. This enzyme activity in males (1.27 ± 1.06 IU/g·Hb) is significantly lower than in females (2.98 ± 1.57 IU/g·Hb) (p < 0.0001). The enzyme activity of the heterozygous-homozygous females and heterozygous females-hemizygous males was found to be significantly different (p < 0.05), which is interpreted due to random X-inactivation. For G6PD molecular characteristics, Viangchan (c.871G>A), Canton (c.1376G>T) and Kaiping (c.1388G>A) variants were the most dominant, accounting for 24.48%, 17.70%, and 22.42%, respectively, whereas the highest frequency of complex variants was observed in Viangchan/Silent with 20.35%. In terms of G6PD activity, the Union variant presented the lowest mean value (1.03 IU/g·Hb) compared to the other variants (p < 0.05). Computational analysis using Polyphen-2 tool investigated that all variants were relative to G6PD deficiency and separated the levels as benign and damaged. The result will establish effective methods to screen G6PD variants in Vietnam.

Glucose-6-Phosphate Dehydrogenase Deficiency and its Association with Malaria in the Administrative Divisions of Lagos State, Nigeria

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of red blood cells' most common inherited enzyme disorders. It is currently believed to affect approximately 500 million individuals worldwide. The deficiency could result in several hematological conditions, including acute hemolytic anemia, neonatal jaundice, and kernicterus. Aim: This study aimed to determine the prevalence of G6PD deficiency in the five administrative divisions of Lagos State. The association between malaria and G6PD deficiency was also investigated. Materials and Methods: A total of 105 participants, comprising 63 (60%) males and 42 (40%) females, were recruited from five locations for this study. Two milliliters of venous blood were collected and divided into three portions for G6PD enzyme assay, hematological parameter, and malaria diagnosis. G6PD enzyme level was determined using a quantitative spectrophotometric assay, whereas the malaria parasite was examined using microscopy and rapid diagnostic test kits. Results: An overall prevalence of G6PD deficiency was 21%. There was no significant difference in prevalence between males (22.2%) and females (19%), whereas a marginally higher G6PD activity in males (10.15 ± 0.50 vs. 8.61 ± 0.31 U/g Hb) (P &lt; 0.05) was recorded. Although there were slight differences in prevalence obtained in the five sampling locations, however, the one-way analysis of variance of the G6PD activity levels showed no significant difference between any pairs (P = 0.05). Furthermore, the results obtained from this study showed no association between malaria and G6PD deficiency (χ 2 = 1.432, P = 0.231). Conclusions: The study found a relatively high prevalence of G6PD deficiency in the Nigerian subpopulation, indicating that G6PD deficiency is common in this environment. This emphasizes the need for a quantitative G6PD assay as part of laboratory investigations for those presenting with an episode of acute hemolytic anemia in this geographical region of the country.

Screenıng of antıoxıdant enzymes superoxıde dısmutase (sod), catalase (cat) and glucose-6-phosphate dehydrogenase (g6pd) actıvıtıes ın persons of dıfferent age groups ın kahramanmaras regıon

Amaç: Bu çalışma Kahramanmaraş yöresinde ikamet eden sağlıklı bireylerde yaşlarına göre eritrosit metabolizmasında yer&#x0D; alan antioksidan enzimlerin aktivitelerini tespit etmek amacı ile yapılmıştır.&#x0D; Gereç ve Yöntemler: Eritrosit metabolizmasında yer alan Glukoz-6-fosfat Dehidrogenaz (G6PD), Süperoksit Dismutaz&#x0D; (SOD) ve Katalaz (CAT) enzimlerinin yokluğunu veya yetersizliğini tespit etmek maksadıyla 0-125 yaşları arasında 281&#x0D; sağlıklı birey çalışmaya dahil edilmiştir. Çalışma grubuna alınan bireylerin hematolojik verileri normal değerdedir.&#x0D; Bulgular: G6PD ve CAT aktiviteleri Beutler Metodu ile SOD aktivitesi Fridovich Metodu ile saptanmıştır. Üç bireyde G6PD&#x0D; enzim eksikliği (sıfır aktivite) ve yedi bireyde katalaz enzim yetersizliği saptanmıştır.&#x0D; Sonuç: Bu çalışmada yaşlanma ile G6PD ve CAT aktivitelerinin arttığı, SOD aktivitesinin ise azaldığı (p0,05). Sonuç olarak, yaşlanma&#x0D; ile oksidatif stres arasında pozitif bir korelasyon olduğu kanısına varılmıştır.

Biochemical Studies on the Colorectal Tissues of Wistar Rats Treated with Methanol Leaf and Stem Bark Extracts of Annona muricata (Soursop).

Annona muricata(AMC), is a tropical plant species of theAnnonaceaefamily known for its medicinal uses in ameliorating and/or protecting several organs and tissues in the body. In this study we elucidated the influence of the methanol extracts of AMC leaf and stem bark on the biochemical and histological integrity of the colorectum. Different doses (100, 200, 400, 600, and 800mg of extract/kg body weight) of methanol extracts of the leaves and stembark were orally administered to adult male Wistar rats of average weight (100 - 150 g) for 28 days. At the end of the experimental period, the rats were sacrificed and colorectal tissues harvested for analyses. Adenosine triphosphatase (ATPases), lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6PD) activities, and tissue protein (TP) concentration, were evaluated by colorimetric method using appropriate test kits.The results in the colorectal tissue analysed showed that total ATPase, LDH and G6PD (energy markers) activities increased significantly in the groups which received methanol leaf and stem bark extracts of AMC when compared with control. However, a general decrease was observed in TP and Na+/K+-ATPase activity but there was a twist in Na+/K+-ATPase activity in stem bark doses of 200mg/kg and 400mg/kg which showed significant increases in dose dependent manner when compared with the control. Even though G6PD activity showed fluctuating patterns for both extracts, the highest dose (800mg/kg) reflected the most significant increase when compared with the control. The histology confirmed the toxicological results by the biochemical parameters. Under the condition of this study, we inferred that the methanol leaf and stem-bark extracts of AMC may significantly influence the enzymes by reducing and increasing total ATPase and Na+/K+-ATPase activities depending on the doses and administration should therefore depend on the desired outcome.

Investigation of In Vitro Effect and Molecular Docking of Aluminum on Glucose-6-Phosphate Dehydrogenase Activity

Aim: Aluminum is one of the elements that is widely used in many sectors and is the most abundant element in nature. The harm of aluminum, which was thought to be harmless until recently and is actively used in daily life, is open to discussion. In this study, it was aimed to investigate the effect of Aluminum Sulphate [Al2(SO4)3] on Glucose-6-Phosphate Dehydrogenase (G6PDH) activity, which is a key enzyme that catalyzes the first step of the pentose phosphate pathway (PFP). In addition, enzyme activity are detailed with molecular docking studies. For the purpose of examining in vitro effect of Aluminium on G6PDH, 4 different concentration of substrate (D-glucose-6-P) (01.M, 0.08M, 0.05M, 0.03M) prepared and 10mM, 30mM Al2(SO4)3 was added G6PDH envoriment. G6PDH activity was measured by spectrofotometrically. Molecular docking studies were performed with DockingServer and HEX 8.0.0 programs. With the data obtained, the Vmax of G6PDH was calculated as 3.33 and Km=0.0323. When 10 mM and 30mM Al2(SO4)3 were added to the reaction environment, it was observed that there was a decrease in enzyme activity by 24.92% and 57.06%, respectively. It was observed that the increase in Al2(SO4)3 concentration was an uncompetitive inhibition due to a significant decrease in both Km and Vmax values of the enzyme.

The Possible Role of Glucose-6-Phosphate Dehydrogenase in the SARS-CoV-2 Infection.

Glucose-6-phosphate dehydrogenase (G6PD) is the second rate-limiting enzyme of the pentose phosphate pathway. This enzyme is present in the cytoplasm of all mammalian cells, and its activity is essential for an adequate functioning of the antioxidant system and for the response of innate immunity. It is responsible for the production of nicotinamide adenine dinucleotide phosphate (NADPH), the first redox equivalent, in the pentose phosphate pathway. Viral infections such as SARS-CoV-2 may induce the Warburg effect with an increase in anaerobic glycolysis and production of lactate. This condition ensures the success of viral replication and production of the virion. Therefore, the activity of G6PD may be increased in COVID-19 patients raising the level of the NADPH, which is needed for the enzymatic and non-enzymatic antioxidant systems that counteract the oxidative stress caused by the cytokine storm. G6PD deficiency affects approximately 350–400 million people worldwide; therefore, it is one of the most prevalent diseases related to enzymatic deficiency worldwide. In G6PD-deficient patients exposed to SARS-CoV-2, the amount of NADPH is reduced, increasing the susceptibility for viral infection. There is loss of the redox homeostasis in them, resulting in severe pneumonia and fatal outcomes.

N-Acetylcysteine protects against cobalt chloride-induced endothelial dysfunction by enhancing glucose-6-phosphate dehydrogenase activity.

Hypoxia‐induced endothelial dysfunction is known to be involved in the pathogenesis of several vascular diseases. However, it remains unclear whether the pentose phosphate pathway (PPP) is involved in regulating the response of endothelial cells to hypoxia. Here, we established an in vitro model by treating EA.hy926 (a hybrid human umbilical vein cell line) with cobalt chloride (CoCl2; a chemical mimic that stabilizes HIF‐1α, thereby leading to the development of hypoxia), and used this to investigate the involvement of PPP by examining expression of its key enzyme, glucose‐6‐phosphate dehydrogenase (G6PD). We report that CoCl2 induces the accumulation of HIF‐1α, leading to endothelial cell dysfunction characterized by reduced cell viability, proliferation, tube formation, and activation of cytokine production, accompanied with a significant decrease in G6PD expression and activity. The addition of 6‐aminonicotinamide (6‐AN) to inhibit PPP directly causes endothelial dysfunction. Additionally, N‐Acetylcysteine (NAC), a precursor of glutathione, was further evaluated for its protective effects; NAC displayed a protective effect against CoCl2‐induced cell damage by enhancing G6PD activity, and this was abrogated by 6‐AN. The effects of CoCl2 and the involvement of G6PD in endothelial dysfunction have been confirmed in primary human aortic endothelial cells. In summary, G6PD was identified as a novel target of CoCl2‐induced damage, which highlighted the involvement of PPP in regulating the response of endothelial cell CoCl2. Treatment with NAC may be a potential strategy to treat hypoxia or ischemia, which are widely observed in vascular diseases.