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Increased aerobic glycolysis is a metabolic hallmark of proinflammatory leukocytes including macrophages and T cells. To take up glucose from the environment and fuel glycolysis, activated leukocytes upregulate the glucose transporter GLUT1. The orally bioavailable selective GLUT1 inhibitor BAY-876 was developed primarily as an anti-tumor drug. Our study assessed its activity on activated macrophages and CD4 + T cells. BAY-876 significantly attenuated glucose uptake by cultured CD4 + T cells and macrophages by 41% and 15%, respectively. Extracellular flux analysis of activated CD4 + T cells in vitro showed that BAY-876 significantly decreases glycolytic proton flux rate and lactate production, effects that are accompanied by an increased oxidative phosphorylation-mediated ATP production rate, leaving intracellular ATP levels per cell unchanged. However, GLUT1 inhibition reduced CD4 + T cell proliferation without compromising cell viability and reduced IFN-γ secretion by 20%. Moreover, TNF secretion from macrophages was reduced by 27%. We conclude that GLUT1-specific inhibitors, like BAY-876, deserve further in vivo testing in a broad range of (auto-) inflammatory disease models., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Activating mutations in the KEAP1/NRF2 pathway characterize a subset of non-small cell lung cancer (NSCLC) associated with chemoresistance and poor prognosis. We herein evaluated the relationship between 64 oxidative stress-related genes and overall survival data from 35 lung cancer datasets. Thioredoxin reductase-1 (TXNRD1) stood out as the most significant predictor of poor outcome. In a cohort of NSCLC patients, high TXNRD1 protein levels correlated with shorter disease-free survival and distal metastasis-free survival post-surgery, including a subset of individuals treated with platinum-based adjuvant chemotherapy. Bioinformatics analysis revealed that NSCLC tumors harboring genetic alterations in the NRF2 pathway (KEAP1, NFE2L2 and CUL3 mutations, and NFE2L2 amplification) overexpress TXNRD1, while no association with EGFR, KRAS, TP53 and PIK3CA mutations was found. In addition, nuclear accumulation of NRF2 overlapped with upregulated TXNRD1 protein in NSCLC tumors. Functional cell assays and gene dependency analysis revealed that NRF2, but not TXNRD1, has a pivotal role in KEAP1 mutant cells' survival. KEAP1 mutants overexpress TXNRD1 and are less susceptible to the cytotoxic effects of the TXNRD1 inhibitor auranofin when compared to wild-type cell lines. Inhibition of NRF2 with siRNA or ML-385, and glutathione depletion with buthionine-sulfoximine, sensitized KEAP1 mutant A549 cells to auranofin. NRF2 knockdown and GSH depletion also augmented cisplatin cytotoxicity in A549 cells, whereas auranofin had no effect. In summary, these findings suggest that TXNRD1 is not a key determinant of malignant phenotypes in KEAP1 mutant cells, although this protein can be a surrogate marker of NRF2 pathway activation, predicting tumor recurrence and possibly other aggressive phenotypes associated with NRF2 hyperactivation in NSCLC., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Glioblastoma multiforme is the most aggressive type of primary brain tumor associated with few therapeutic opportunities and poor prognosis. In this study, we evaluated the efficacy of combining temozolomide (TMZ) with suberoylanilide hydroxamic acid (SAHA) - a specific histone deacetylases inhibitor - in glioma models in vitro and in vivo. In glioma cell lines, combined TMZ/SAHA promoted more cytotoxicity, G2/M arrest and apoptosis than either drugs alone. G2/M arrest was detected as soon as 24 h post drug exposure and preceded apoptosis, which occurred from 72 h treatment. TMZ and SAHA, alone or combined, also stimulated autophagy as evaluated by means of acridine orange staining and immunodetection of LC3I-II conversion and p62/SQSTM1 degradation. Time-course of autophagy accompanied G2/M arrest and preceded apoptosis, and blockage of late steps of autophagy with chloroquine (CQ) augmented SAHA/TMZ toxicity leading to apoptosis. In orthotopic gliomas in vivo, combined SAHA/TMZ showed better antitumor efficacy than either drugs alone, and adding CQ to the regimen improved antiglioma effects of SAHA and TMZ monotherapies without further benefit on combined SAHA/TMZ. In summary, the herein presented data suggest that autophagy acts as a protective response that impairs efficacy of SAHA and TMZ. Inhibiting autophagy termination with CQ may offer means to improve antitumor effects of SAHA and TMZ in gliomas and possibly other cancers., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Sexual hormone deficiency has been associated with metabolic changes, oxidative stress and subclinical inflammation in postmenopausal women. Hormone replacement therapies are effective in many instances, even though some patients either do not respond or are not eligible. The aim of this study was to evaluate the impact of short- (15 days) versus long-term (60 days) sexual hormone depletion and whether antioxidant supplementation with N-acetylcysteine (NAC) and alpha-lipoic acid (LA) improves oxidative stress, metabolic, and inflammatory parameters in ovariectomized (OVX) rats. Short-term OVX rapidly depleted circulating estrogen, causing uterine atrophy and body weight gain without affecting oxidative damage, inflammatory and lipid metabolism markers. In contrast, long-term OVX augmented oxidative damage in serum and peripheral tissues as well as increased serum total cholesterol, TNF-α and IL6 levels. Triglycerides, glucose and HDL cholesterol were not altered. Long-term OVX-induced oxidative stress was associated with depletion of GSH and total non-enzymatic antioxidants as well as decreased activity of Glutathione Peroxidase (GPx) and Glutathione Reductase (GR), but not Superoxide Dismutase (SOD) and Catalase (CAT). NAC and LA supplementation prevented GSH and total non-enzymatic antioxidants depletion as well as restored GPx and GR activities, TNF-α, IL6 and cholesterol in OVX rats. NAC and LA effects appear to be independent on NRF2 activation and estrogen-like activity, since NAC/LA did not promote NRF2 activation and were not able to emulate estrogen effects in OVX rats and estrogen-receptor-positive cells. The herein presented data suggest that NAC and LA may improve some deleterious effects of sexual hormone depletion via estrogen-independent mechanisms., (Copyright © 2019 Elsevier Inc. All rights reserved.)