Glutathione S-transferase Alpha Research Articles

GSTA1/CTNNB1 axis facilitates sorafenib resistance via suppressing ferroptosis in hepatocellular carcinoma

The emergence of sorafenib resistance has become a predominant impediment and formidable dilemma in the therapeutic approach for hepatocellular carcinoma (HCC). Although the approval of next-generation drugs as alternatives to sorafenib is a significant development, the concurrent use of inhibitors that target additional key molecular pathways remains an effective strategy to mitigate the acquisition of resistance. Here, we identified Glutathione S-Transferase Alpha 1 (GSTA1) as a critical modulator of sorafenib resistance (SR) in hepatocellular carcinoma (HCC) based on our findings from experiments conducted on recurrent liver cancer tissues, xenograft mouse models, organoids, and sorafenib-resistant cells. Elevated GSTA1 levels are strongly associated with adverse clinical prognoses. The knockout of GSTA1 reinstates sorafenib sensitivity, whereas its overexpression attenuates drug efficacy. Mechanistically, GSTA1 enhances the accumulation of lipid peroxides and suppresses ferroptosis by exerting its peroxidase function to regulate the SR. Notably, the upregulation of GSTA1 expression is mediated by the transcription factor CTNNB1 (β-catenin), resulting in the formation of a cytoplasmic complex between GSTA1 and CTNNB1. This complex facilitates the nuclear translocation of CTNNB1, establishing a positive feedback loop. The combined use of GSTA1 and CTNNB1 inhibitors demonstrated synergistic anti-tumour effects through the induction of ferroptosis both in vitro and in vivo. Our findings reveal a novel regulatory role of the GSTA1/CTNNB1 axis in ferroptosis, suggesting that targeting GSTA1 and CTNNB1 could be a promising strategy to circumvent sorafenib resistance in HCC.

Precision medicine in intestinal ischemia: the emerging role of biomarkers.

Intestinal ischemia (IIs) is a significant gastrointestinal condition characterized by reduced blood flow to the bowel, leading to inflammation and injury. Early diagnosis and management are crucial for preventing severe complications. Under this point of view, circulating biomarkers can enhance patient stratification and guide therapeutic decisions. Fatty acid-binding proteins (FABPs), specifically I-FABP and L-FABP, are small cytosolic proteins released upon enterocyte membrane integrity loss, with elevated plasma levels indicating early intestinal ischemia. Stromal Cell-Derived Factor-1 (SDF-1) regulates stem cell function and shows significantly higher levels in patients with IIs and cardiovascular disease compared to controls. D-Lactate, a bacterial fermentation byproduct, is another significant marker, with higher serum levels observed in intestinal ischemia cases. Alpha-glutathione S-transferase combats intracellular oxidative stress, with significantly elevated levels in acute mesenteric ischemia patients. Additionally, SM22, a small smooth muscle protein, shows higher plasma levels in patients with transmural ischemia compared to those with mucosal ischemic lesions and healthy controls. These biomarkers are promising for their roles in early detection and differentiation of IIs from other gastrointestinal conditions. Therapeutic strategies, including anti-inflammatory therapies, have shown efficacy in managing IIs symptoms and preventing recurrence. This review aims to inform clinicians and researchers about the current advancements in biomarker research and therapeutic approaches for IIs, emphasizing the importance of integrating these biomarkers and treatments into clinical practice to improve the management and prognosis of the disease.

Management of Busulfan-Induced Lung Injury in Pediatric Patients with High-Risk Neuroblastoma

Background/Objectives: Integrating the cytotoxic drug busulfan into a high-dose chemotherapy regimen prior to autologous hematopoietic stem cell rescue in patients with high-risk neuroblastoma has improved the survival of children battling this deadly disease. Busulfan-induced toxicities can, however, be severe. Here, we describe the diagnosis and successful treatment of acute pulmonary injury by total-body-weight-adjusted busulfan therapy in two children with high-risk neuroblastoma. Case series: Patient 1 developed life-threatening biphasic acute respiratory failure on days +60 and +100 after busulfan therapy, requiring intubation and invasive mechanical ventilation. Despite intensive anti-inflammatory and immunomodulatory therapy, including systemic corticosteroids, topical inhalation regimens, azithromycin, nintedanib and extracorporal photopheresis, patient 1 required extended intensive care measures and non-invasive respiratory support for a total of 20 months. High-resolution computed tomography showed diffuse intra-alveolar and interstitial patterns. Patient 2 developed partial respiratory failure with insufficient oxygen saturation and dyspnea on day +52 after busulfan therapy. Symptoms were resolved after 6 months of systemic corticosteroids, topical inhalation regimens and azithromycin. High-resolution computed tomography showed atypical pneumonic changes with ground-glass opacities. While both patients fully recovered without evidence of pulmonary fibrosis, cancer therapy had to be paused and then modified until full recovery from busulfan-induced lung injury. Conclusions: Busulfan-induced lung injury requires prompt diagnosis and intervention. Symptoms and signs are nonspecific and difficult to differentiate from other causes. Therapeutic busulfan drug level monitoring and the identification of patients at risk for drug overdosing through promoter polymorphisms in the glutathione S-transferase alpha 1 gene encoding the main enzyme in busulfan metabolism are expected to reduce the risk of busulfan-induced toxicities.

Biomarkers In Prediction of Acute Mesenteric Ischaemia: a prospective multicentre study (BIPAMI study): a study protocol

BackgroundAcute mesenteric ischaemia (AMI) is a life-threatening disease where early diagnosis is critical to avoid morbidity and mortality from extensive irreversible bowel necrosis. Appropriate prediction of presence of bowel necrosis is currently not available but would help to choose the optimal method of treatment.The study aims to identify combinations of biomarkers that can reliably identify AMI and distinguish between potentially reversible and irreversible bowel ischaemia.MethodsThis is a prospective multicentre study. Adult patients with clinical suspicion of AMI (n = 250) will be included. Blood will be sampled on admission, at and after interventions, or during the first 48 h of suspicion of AMI if no intervention undertaken. Samples will be collected and the following serum or plasma biomarkers measured at Tartu University Hospital laboratory: intestinal fatty acid-binding protein (I-FABP), alpha-glutathione S-transferase (Alpha- GST), interleukin 6 (IL-6), procalcitonin (PCT), ischaemia-modified albumin (IMA), D-lactate, D-dimer, signal peptide-CUB-EGF domain-containing protein 1 (SCUBE-1) and lipopolysaccharide-binding protein (LBP). Additionally, more common laboratory markers will be measured in routine clinical practice at study sites.Diagnosis of AMI will be confirmed by computed tomography angiography, surgery, endoscopy or autopsy.Student’s t or Wilcoxon rank tests will be used for comparisons between transmural vs. suspected (but not confirmed) AMI (comparison A), confirmed AMI of any stage vs suspected AMI (comparison B) and non-transmural AMI vs transmural AMI (comparison C). Optimal cut-off values for each comparison will be identified based on the AUROC analysis and likelihood ratios calculated. Positive likelihood ratio > 10 (> 5) and negative likelihood ratio < 0.1 (< 0.2) indicate high (moderate) diagnostic accuracy, respectively. All biomarkers with at least moderate accuracy will be entered as binary covariates (using the best cutoffs) into the multivariable stepwise regression analysis to identify the best combination of biomarkers for all comparisons separately. The best models for each comparison will be used to construct a practical score to distinguish between no AMI, non-transmural AMI and transmural AMI.DiscussionAs a result of this study, we aim to propose a score including set of biomarkers that can be used for diagnosis and decision-making in patients with suspected AMI.Trial registrationNCT06212921 (Registration Date 19–01-2024).

Retracing from Outcomes to Causes: NRF2-Driven GSTA4 Transcriptional Regulation Controls Chronic Inflammation and Oxidative Stress in Atopic Dermatitis Recurrence

Atopic dermatitis (AD), a chronic and recurrent inflammatory skin disorder, presents a high incidence and imposes a substantial economic burden. Preventing its recurrence remains a significant challenge in dermatological therapy owing to poorly understood underlying mechanisms. In our study, we adopted a strategy of tracing the mechanisms of recurrence from clinical outcomes. We developed a mouse model of recurrent AD and applied clinically validated treatment regimens. Transcriptomic analyses revealed a pronounced enrichment in the glutathione metabolic pathway in the treated group. Through integrated bioinformatics and invivo validation, we identified glutathione S-transferase alpha 4 (GSTA4) as a pivotal mediator in AD recurrence. Immunohistochemical analysis demonstrated decreased GSTA4 expression in lesions from patients with AD. Functionally, invitro overexpression of GSTA4 significantly curtailed AD-like inflammatory responses and ROS production. Moreover, we discovered that NRF2 transcriptional activity regulates GSTA4 expression and function. Our treatment notably augmented NRF2-mediated GSTA4 transcription, yielding pronounced anti-inflammatory and ROS-neutralizing effects. Conclusively, our findings implicate GSTA4 as a critical factor in the recurrence of AD, particularly in the context of oxidative stress and chronic inflammation. Targeting the NRF2-GSTA4 axis emerges as a promising anti-inflammatory and antioxidative strategy for preventing AD recurrence.

Upregulation of Hepatic Glutathione S-Transferase Alpha 1 Ameliorates Metabolic Dysfunction-Associated Steatosis by Degrading Fatty Acid Binding Protein 1.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common metabolic disease of the liver, characterized by hepatic steatosis in more than 5% of hepatocytes. However, despite the recent approval of the first drug, resmetirom, for the management of metabolic dysfunction-associated steatohepatitis, decades of target exploration and hundreds of clinical trials have failed, highlighting the urgent need to find new druggable targets for the discovery of innovative drug candidates against MASLD. Here, we found that glutathione S-transferase alpha 1 (GSTA1) expression was negatively associated with lipid droplet accumulation in vitro and in vivo. Overexpression of GSTA1 significantly attenuated oleic acid-induced steatosis in hepatocytes or high-fat diet-induced steatosis in the mouse liver. The hepatoprotective and anti-inflammatory drug bicyclol also attenuated steatosis by upregulating GSTA1 expression. A detailed mechanism showed that GSTA1 directly interacts with fatty acid binding protein 1 (FABP1) and facilitates the degradation of FABP1, thereby inhibiting intracellular triglyceride synthesis by impeding the uptake and transportation of free fatty acids. Conclusion: GSTA1 may be a good target for the discovery of innovative drug candidates as GSTA1 stabilizers or enhancers against MASLD.

Abstract 5635: TPM4 overexpression promotes colon epithelial cell tumorigenesis in vitro and correlates with human colon tumor progression in vivo

Abstract Because colon cancer still exerts a heavy burden on human health, we are interested in identifying very early events in colon epithelial cell tumorigenesis in order to develop strategies to treat and possibly prevent colon carcinogenesis. We hypothesize that aberrant expression of genes involved in crypt-luminal colon epithelial cell migration, needed for proliferative, undifferentiated stem cells at the crypt bottom to mature into growth arrested, mature effector cells near the lumen, may disrupt normal differentiation and initiate events that can trigger the transition from a normal to premalignant state in colon epithelial cells. Forced upregulation of tropomyosin 4 (TPM4), an actin-binding protein that exerts many effects on contractility and migration, prevents certain aspects of Caco2 maturation induced by contact inhibition of growth, including increased expression of the digestive enzyme sucrose isomaltase and glutathione S-transferase alpha 1. Furthermore, TPM4.2-overexpressing cells exhibit numerous morphological abnormalities. Compared to untransfected Caco2 cells and empty-vector stable transfectant controls, TPM4.2-overexpressing Caco2 cell clones elaborate aberrant thin membrane protrusions and expanded membrane ruffles. Particularly striking are defective maintenance of dome structures at middle (day 14) and late (day 21) time points of induced differentiation in TPM4.2-overeexpressing clones. We further hypothesize that TPM4 is overexpressed in human colon tumors, particularly at early stages of tumorigenesis. In order to test this hypothesis, we examined TPM4 RNA expression in datasets obtained from human colon tissue at premalignant as well as tumorigenic stages. TPM4 trends toward overexpression in premalignant, relative to normal, human colon tissue (uninvolved mucosa from patients with familial adenomatous polyposis, or FAP) and is significantly overexpressed in adenocarcinoma tissue relative to normal controls. Interestingly, TPM4 overexpression may be more pronounced at earlier, rather than later, stages of adenocarcinoma. Our results suggest that aberrant TPM4 overexpression in colon epithelial cells can promote adoption of a tumorigenic state. Certain aspects of Caco2 cell maturation are disrupted by forced TPM4 overexpression during induced differentiation, and TPM4 overexpression correlates with early stages of colon tumorigenesis. Misregulation of TPM4 gene expression may therefore represent a critical molecular event that can block normal differentiation and induce early events in colon epithelial cell tumorigenesis. TPM4 expression level may therefore prove to be a useful biomarker that can, along with other diagnostics, help to determine tumorigenic progression in human colon tissue and to develop novel strategies to prevent colon cancer and treat it at early stages. Citation Format: Giulio Ferrero, Barbara Pardini, Alessio Naccarati, Michael Papetti. TPM4 overexpression promotes colon epithelial cell tumorigenesis in vitro and correlates with human colon tumor progression in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5635.

Effects of Aspirin Eugenol Ester on Liver Oxidative Damage and Energy Metabolism in Immune-Stressed Broilers.

The aim of this study was to investigate the effects of aspirin eugenol ester (AEE) on liver oxidative damage and energy metabolism in immune-stressed broilers. In total, 312 broilers were divided into 4 groups (saline, LPS, SAEE, and LAEE). Broilers in the saline and LPS groups were fed a basal diet; the SAEE and LAEE groups had an added 0.01% AEE in their diet. Broilers in the LPS and LAEE groups were injected with lipopolysaccharides, while the saline and SAEE groups were injected with saline. Results showed that AEE increased the body weight, average daily gain, and average daily feed intake, as well as decreasing the feed conversion ratio of immune-stressed broilers. AEE protects against oxidative damage in immune-stressed broiler livers by elevating the total antioxidant capacity, superoxide dismutase activity, and glutathione S-transferase alpha 3 (GSTA3) and glutaredoxin 2 (GLRX2) expression, while decreasing malondialdehyde content. AEE lessened inflammation by reducing prostaglandin-F2α production and prostaglandin-endoperoxide synthase 2 (PTGS2) and interleukin-1beta (IL-1β) expression. AEE decreased oxidative phosphorylation rates by increasing succinic acid levels and lowering both adenosine diphosphate (ADP) levels and ceroid lipofuscinosis neuronal 5 (CLN5) expression. AEE modulated the metabolism of phenylalanine, tyrosine, lipids, and cholesterol by reducing the phenyllactate and L-arogenate levels, lowering dopachrome tautomerase (DCT) and apolipoprotein A4 (APOA4) expression, and increasing phenylpyruvic acid and dopa decarboxylase (DDC) expression. In summary, AEE can effectively alleviate liver oxidative damage and energy metabolism disorders in immune-stressed broilers.

Association between oxidative stress and chronic orofacial pain and potential druggable targets: Evidence from a Mendelian randomization study.

Oxidative stress indicators affect chronic orofacial pain (COFP), but how to reduce these effects is uncertain. 11 oxidative stress biomarkers were collected as exposures, while four forms of COFP were chosen as outcomes for Mendelian randomization (MR) study. The effect estimates between oxidative stress and COFP were calculated using inverse variance-weighted MR (IVW-MR). Then, functional mapping and annotation (FUMA) was utilized in order to carry out SNP-based functional enrichment analyses. In addition, the IVW-MR method was applied to combine effect estimates when using genetic variants associated with oxidative stress biomarkers as an instrument for exploring potential druggable targets. The results indicated that oxidative stress biomarkers (causal OR of uric acid (UA), 0.998 for myofascial pain, 95% CI 0.996-1.000, p < .05; and OR of glutathione transferase (GST), 1.002 for dentoalveolar pain, 95% CI 1.000-1.003, p < .05) were significantly linked with the probability of COFP. Functional analysis also demonstrated that UA and myofascial pain genes were prominent in nitrogen and uracil metabolism, while GST and dentoalveolar pain genes were enriched in glutathione metabolism. Also, the study provided evidence that solute carrier family 2 member 9 (SLC2A9) and glutathione S-transferase alpha 2 (GSTA2) cause discomfort in the myofascial pain (OR = 1.003, 95% CI 1.000-1.006; p < .05) and dentoalveolar region (OR = 1.001, 95% CI 1.000-1.002; p < .05), respectively. In conclusion, this MR study indicates that genetically predicted myofascial pain was significantly associated with decreased UA and dentoalveolar pain was significantly associated with increased GST level. SLC2A9 inhibitor and GSTA2 inhibitor were novel chronic orofacial pain therapies and biomarkers, but clinical trials are called to examine if these oxidative biomarkers have the protective effect against orofacial pain, and further research are needed to explore the underlying mechanisms.

Piceatannol Alleviates Deoxynivalenol-Induced Damage in Intestinal Epithelial Cells via Inhibition of the NF-κB Pathway.

Deoxynivalenol (DON) is a common mycotoxin that is widely found in various foods and feeds, posing a potential threat to human and animal health. This study aimed to investigate the protective effect of the natural polyphenol piceatannol (PIC) against DON-induced damage in porcine intestinal epithelial cells (IPEC-J2 cells) and the underlying mechanism. The results showed that PIC promotes IPEC-J2 cell proliferation in a dose-dependent manner. Moreover, it not only significantly relieved DON-induced decreases in cell viability and proliferation but also reduced intracellular reactive oxygen species (ROS) production. Further studies demonstrated that PIC alleviated DON-induced oxidative stress damage by increasing the protein expression levels of the antioxidant factors NAD(P)H quinone oxidoreductase-1 (NQO1) and glutamate-cysteine ligase modifier subunit (GCLM), and the mRNA expression of catalase (CAT), Superoxide Dismutase 1 (SOD1), peroxiredoxin 3 (PRX3), and glutathione S-transferase alpha 4 (GSTα4). In addition, PIC inhibited the activation of the nuclear factor-B (NF-κB) pathway, downregulated the mRNA expression of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α) to attenuate DON-induced inflammatory responses, and further mitigated DON-induced cellular intestinal barrier injury by regulating the protein expression of Occludin. These findings indicated that PIC had a significant protective effect against DON-induced damage. This study provides more understanding to support PIC as a feed additive for pig production.

"Evaluation of Kidney Injury Molecule-1 (KIM-1) and Alpha Glutathione Transferase (αGST) Among Selected Motor Park Workers in Ado-Ekiti Consuming Herbal- based Products: A Cross Sectional Study"

"Evaluation of Kidney Injury Molecule-1 (KIM-1) and Alpha Glutathione Transferase (αGST) Among Selected Motor Park Workers in Ado-Ekiti Consuming Herbal- based Products: A Cross Sectional Study"

The Impact of Biomarkers on the Early Detection of Acute Mesenteric Ischemia.

acute mesenteric ischemia (AMI) is a life-threatening condition that is caused by inadequate blood flow through the mesenteric vessel and is related to high mortality rates due to systemic complications. This study aims to systematically review the available literature concerning the major findings of possible biomarkers for early detection of acute mesenteric ischemia in the human population. studies that measured the performance of biomarkers during acute mesenteric ischemia were identified with the search of PubMed, Embase, Medline, and Cochrane library. from a total of 654 articles, 46 articles examining 14 different biomarkers were filtered, falling within our inclusion criteria. Intestinal fatty acid-binding protein (I-FABP) was the most commonly researched biomarker regarding AMI, with sensitivity ranging from 61.5% to 100% and specificity ranging from 40% to 100%. The second most commonly researched biomarker was D-dimer, with a sensitivity of 60-100% and a specificity of 18-85.71%. L-lactate had a sensitivity of 36.6-90.91% and a specificity of 64.29-96%. Several parameters within the blood count were examined as potential markers for AMI, including NLR, PLR, MPV, RDW, DNI, and IG. Citrulline, interleukin 6 (IL-6), and procalcitonin (PCT) were the least-researched biomarkers. different biomarkers showed different accuracies in detecting AMI. I-FABP and D-dimer have been the most researched and shown to be valuable in the diagnosis of AMI, whereas L-lactate could be used as an additional tool. Ischemia-modified albumin (IMA), alpha glutathione S-transferase (αGST), interleukin 6 (IL-6), and citrulline showed potential use in their respective studies. However, further research needs to be done on larger sample sizes and with controls to reduce bias. Several studies showed that neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), mean platelet volume (MPV), red-cell distribution width (RDW), delta neutrophil index (DNI), and immature granulocytes (IGs) might be useful, as well at the same time be widely distributed and affordable in combination with other markers presenting higher specificity and sensitivity.

Colonic expression of glutathione S-transferase alpha 4 and 4-hydroxynonenal adducts is correlated with the pathology of murine colitis-associated cancer

Chronic inflammation-induced oxidative stress is an important driving force for developing colitis-associated cancer (CAC). 4-hydroxynonenal (4-HNE) is a highly reactive aldehyde derived from lipid peroxidation of ω-6 polyunsaturated fatty acids that contributes to colorectal carcinogenesis. Glutathione S-transferase alpha 4 (Gsta4) specifically conjugates glutathione to 4-HNE and thereby detoxifies 4-HNE. The correlation of these oxidative biomarkers with the pathological changes in CAC is, however, unclear. In this study, we investigated the expression of Gsta4 and 4-HNE adducts in azoxymethane/dextran sulfate sodium (AOM/DSS)-induced murine CAC, and analyzed the correlations of 4-HNE and Gsta4 with inflammatory cytokines and the pathological scores in the colon biopsies. Real-time quantitative PCR showed that expression of IL6, TNFα, and Gsta4 sequentially increased in colon tissues for mice treated with DSS for 1, 2, and 3 cycles, respectively. Moreover, immunohistochemical staining showed remarkably increased expression of 4-HNE adducts, Gsta4, TNFα, and IL6 in the colon biopsies after 3 cycles of DSS treatment. Correlation analysis demonstrated that 4-HNE adducts in the colon biopsies were positively correlated with Gsta4 expression. Additionally, the expression of Gsta4 and 4-HNE adducts were strongly correlated with the pathological changes of colon, as well as the expression of TNFα and IL6 in colon tissues. These results provide evidence for the association of oxidative biomarkers Gsta4 and 4-HNE with the pathological changes of CAC and may help developing novel histopathological biomarkers and prevention targets for CAC.

Association of Genetic and Allelic Variants of Von Willebrand Factor (VWF), Glutathione S-Transferase and Tumor Necrosis Factor Alpha with Ischemic Stroke Susceptibility and Progression in the Saudi Population.

Stroke is a key cerebrovascular disease and important cause of death and disability worldwide, including in the kingdom of Saudi Arabia (KSA). It has a large economic burden and serious socioeconomic impacts on patients, their families and the community. The incidence of ischemic stroke is probably increased by the interaction of GSTT1 and GSTM1 null genotypes with high blood pressure, diabetes and cigarette smoking. The roles of VWF, GSTs and TNF-alpha gene variations in the induction of stroke are still uncertain and require further examination. In the current study, we studied the associations of SNPs in the genes VWF, GSTs and TNF-alpha with stroke in the Saudi population. Genotyping was performed using the ARMS -PCR for TNF-alpha, AS-PCR for VWF and multiplex PCR for GSTs. The study included 210 study subjects: 100 stroke cases and 110 healthy controls. We obtained significant distributions of VWF rs61748511 T > C, TNF-alpha rs1800629 G > A and GST rs4025935 and rs71748309 genotypes between stroke cases and the healthy controls (p < 0.05). The results also indicated that the TNF-alpha A allele was associated with risk of stroke with odd ratio (OR) = 2.22 and risk ratio = RR 2.47, p < 0.05. Similarly, the VWF-TC genotype and C allele were strongly linked with stroke with OR = 8.12 and RR 4.7, p < 0.05. In addition, GSTT1 and GSTT1 null genotype was strongly associated with stroke predisposition with OR = 8.30 and RR = 2.25, p < 0.0001. We conclude that there is a possible strong association between the VWF-T > C, TNF-alpha G > A, GSTT1 gene variants and ischemic stroke susceptibility in the Saudi population. However, future well-designed and large-scale case-control studies on protein-protein interactions and protein functional studies are required to verify these findings and examine the effects of these SNPs on these proteins.

A Review of the Global Microgreens’ Market by most Popular Species Grown, Farming types and Practices, end users, Revenue Generated: Opportunity Analysis, and Industry Forecast

Background: Alcoholic liver damage is caused by long-term and heavy alcohol consumption, which leads to many diseases and even cancer. α-Pinene has been shown to have antioxidant and anti-inflammatory activity, however, it is still unclear the relationship between α-Pinene and alcohol-induced liver injury. The potential molecular mechanisms of α-pinene in reducing alcohol-induced liver injury in mice were investigated in this study. Materials and methods: The C57BL/6 mice were randomly divided into five groups, which were the control groups (physiological saline, 0.2mL per days), alcohol group (50% alcohol, 5 mL/kg bw/day), alcohol with low/medium/high dosage α-pinene treatment group ((7.2 mg/kg bw, 14.4 mg/kg bw, 28.8 mg/kg bw, dissolved in 50% alcohol, Separately). The dosing method for mice is via oral gavage. After 8 weeks of experimentation, mouse serum and liver were collected for further testing. Result: The increased antioxidant enzyme activities demonstrated the alleviated effect of α-pinene against alcohol-induced mouse liver injury. Moreover, in liver tissues, α-pinene promoted nucleus translocation of nuclear factor-erythroid-2-related factor 2 (NRF2) and transcription of antioxidant target genes, including heme oxygenase 1 (HMOX-1 / HO-1), NAD[P]H quinone dehydrogenase 1 (NQO-1), and glutathione S-transferase alpha 1 (Gsta-1). Meanwhile, α-pinene promoted the protein expression of autophagy-related proteins and inhibited the increase of inflammatory factors caused by chronic alcohol intake. Furthermore, α-pinene partially inhibited the activation of apoptotic signaling pathways by increasing the expression of Bcl-2 and decreasing Bax and cleaved caspase-3 proteins. Conclusion: Taken together, our results indicated that α-pinene might alleviate alcoholic liver injury by reducing lipid accumulation, enhancing anti-oxidative stress and anti-inflammatory, activating autophagy, and inhibiting cell apoptosis.

The Alleviated Effect of α-Pinene on Amidst Alcoholic Liver Injury Pathology Through Autophagy Activation in Mice

Background: Alcoholic liver damage is caused by long-term and heavy alcohol consumption, which leads to many diseases and even cancer. α-Pinene has been shown to have antioxidant and anti-inflammatory activity, however, it is still unclear the relationship between α-Pinene and alcohol-induced liver injury. The potential molecular mechanisms of α-pinene in reducing alcohol-induced liver injury in mice were investigated in this study. Materials and methods: The C57BL/6 mice were randomly divided into five groups, which were the control groups (physiological saline, 0.2mL per days), alcohol group (50% alcohol, 5 mL/kg bw/day), alcohol with low/medium/high dosage α-pinene treatment group ((7.2 mg/kg bw, 14.4 mg/kg bw, 28.8 mg/kg bw, dissolved in 50% alcohol, Separately). The dosing method for mice is via oral gavage. After 8 weeks of experimentation, mouse serum and liver were collected for further testing. Result: The increased antioxidant enzyme activities demonstrated the alleviated effect of α-pinene against alcohol-induced mouse liver injury. Moreover, in liver tissues, α-pinene promoted nucleus translocation of nuclear factor-erythroid-2-related factor 2 (NRF2) and transcription of antioxidant target genes, including heme oxygenase 1 (HMOX-1 / HO-1), NAD[P]H quinone dehydrogenase 1 (NQO-1), and glutathione S-transferase alpha 1 (Gsta-1). Meanwhile, α-pinene promoted the protein expression of autophagy-related proteins and inhibited the increase of inflammatory factors caused by chronic alcohol intake. Furthermore, α-pinene partially inhibited the activation of apoptotic signaling pathways by increasing the expression of Bcl-2 and decreasing Bax and cleaved caspase-3 proteins. Conclusion: Taken together, our results indicated that α-pinene might alleviate alcoholic liver injury by reducing lipid accumulation, enhancing anti-oxidative stress and anti-inflammatory, activating autophagy, and inhibiting cell apoptosis.

Protective Effects of PEP-1-GSTA2 Protein in Hippocampal Neuronal Cell Damage Induced by Oxidative Stress.

Glutathione S-transferase alpha 2 (GSTA2), a member of the glutathione S-transferase family, plays the role of cellular detoxification against oxidative stress. Although oxidative stress is related to ischemic injury, the role of GSTA2 against ischemia has not been elucidated. Thus, we studied whether GSTA2 prevents ischemic injury by using the PEP-1-GSTA2 protein which has a cell-permeable protein transduction domain. We revealed that cell-permeable PEP-1-GSTA2 transduced into HT-22 cells and markedly protected cell death via the inhibition of reactive oxygen species (ROS) production and DNA damage induced by oxidative stress. Additionally, transduced PEP-1-GSTA2 promoted mitogen-activated protein kinase (MAPK), and nuclear factor-kappaB (NF-κB) activation. Furthermore, PEP-1-GSTA2 regulated Bcl-2, Bax, cleaved Caspase-3 and -9 expression protein levels. An in vivo ischemic animal model, PEP-1-GSTA2, markedly prevented the loss of hippocampal neurons and reduced the activation of microglia and astrocytes. These findings indicate that PEP-1-GSTA2 suppresses hippocampal cell death by regulating the MAPK and apoptotic signaling pathways. Therefore, we suggest that PEP-1-GSTA2 will help to develop the therapies for oxidative-stress-induced ischemic injury.

Activation of the Keap1/Nrf2 Pathway as an Adaptive Response to an Electrophilic Metabolite of Morphine.

Morphinone (MO) is an electrophilic metabolite of morphine that covalently binds to protein thiols via its α,β-unsaturated carbonyl group, resulting in toxicity in vitro and in vivo. Our previous studies identified a variety of redox signaling pathways that are activated during electrophilic stress. Here, we examined in vitro activation of a signaling pathway involving Kelch-like ECH-associated protein 1 (Keap1) and nuclear factor erythroid 2-related factor 2 (Nrf2) in response to MO. Exposure of HepG2 cells to MO caused covalent modification of Keap1 thiols (evaluated using biotin-PEAC5-maleimide labeling) and nuclear translocation of Nrf2, thereby up-regulating downstream genes encoding ATP binding cassette subfamily C member 2, solute carrier family 7 member 11, glutamate-cysteine ligase catalytic subunit, glutamate-cysteine ligase modifier subunit, glutathione S-transferase alpha 1, and heme oxygenase 1. However, dihydromorphinone, a metabolite of morphine lacking the reactive C7-C8 double bond, had little effect on Nrf2 activation. These results suggest that covalent modification is crucial in the Keap1/Nrf2 pathway activation and that this pathway is a redox signaling-associated adaptive response to MO metabolism.

Structural insights into the interactions of glutathione transferases with a nitric oxide carrier and sodium nitroprusside

Glutathione transferases are detoxification enzymes with multifaceted roles, including a role in the metabolism and scavenging of nitric oxide (NO) compounds in cells. Here, we explored the ability of Trametes versicolor glutathione transferases (GSTs) from the Omega class (TvGSTOs) to bind metal-nitrosyl compounds. TvGSTOs have been studied previously for their ligandin role and are interesting models to study protein‒ligand interactions. First, we determined the X-ray structure of the TvGSTO3S isoform bound to the dinitrosyl glutathionyl iron complex (DNGIC), a physiological compound involved in the storage of nitric oxide. Our results suggested a different binding mode compared to the one previously described in human GST Pi 1 (GSTP1). Then, we investigated the manner in which TvGSTO3S binds three nonphysiological metal-nitrosyl compounds with different metal cores (iron, ruthenium and osmium). We assayed sodium nitroprusside, a well-studied vasodilator used in cases of hypertensive crises or heart failure. Our results showed that the tested GST can bind metal-nitrosyls at two distinct binding sites. Thermal shift analysis with six isoforms of TvGSTOs identified TvGSTO6S as the best interactant. Using the Griess method, TvGSTO6S was found to improve the release of nitric oxide from sodium nitroprusside in vitro, whereas the effects of human GST alpha 1 (GSTA1) and GSTP1 were moderate. Our results open new structural perspectives for understanding the interactions of glutathione transferases with metal-nitrosyl compounds associated with the biochemical mechanisms of NO uptake/release in biological systems.

Temperature alters the oxidative and metabolic biomarkers and expression of environmental stress-related genes in chocolate mahseer (Neolissochilus hexagonolepis).

Long-term acclimation temperature effects on biomarkers of oxidative stress, metabolic stress, expression of heat shock proteins (Hsps), and warm-temperature acclimation related 65-kDa protein (Wap65) were evaluated in the threatened chocolate mahseer (Neolissochilus hexagonolepis). Fifteen-day-old larvae were acclimated to different water temperatures (15, 19, 23-control group, 27, and 31°C) for 60days prior to the sampling for quantification of mRNA, enzyme, nitric oxide, and malondialdehyde (MDA) content. Acclimation to 31°C increased the basal mRNA level of glutathione S-transferase alpha 1 (GSTa1), and activities of catalase (CAT), glutathione reductase (GR), and GST enzymes and but downregulated the expression of superoxide dismutase 1 (SOD1) in the whole-body homogenate. Other antioxidant genes, i.e., CAT and GPx1a, were unaffected at 31°C, and nitric oxide (NO) concentration was significantly lower. In contrast, fish acclimated to 15°C showed an upregulated transcript level of all the antioxidant genes and no significant difference in the CAT, GR, and GST enzymes. Activities of the metabolic enzymes, aspartate transaminase (AST) and alanine transaminase (ALT), were significantly lower at 15°C. The expression of Hsp47 was upregulated at both 15 and 31°C groups, whereas Hsp70 was elevated at 27 and 31°C groups. Wap65-1 transcription did not show significant variation in treatment groups compared to control. Fish in the high (31°C) and low-temperature (15°C) acclimation groups were capable of maintaining oxidative stress by modulating their antioxidant transcripts, enzymes, and Hsps.