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Increasing evidence has demonstrated that oxidative stress impairs oocyte maturation and embryonic development. Conventionally, antioxidants have been applied in vitro systems to improve oocyte maturation and blastocyst rates. Formononetin (FMN) is a flavonoid that has been shown to have various pharmacological effects, including antioxidants. In this study, we delved into the impact of FMN, acting as an antioxidant, on the in vitro development of oocytes and blastocysts within the culture system. FMN supplementation at 0.5 μM enhanced the rate of first polar body extrusion and blastocyst formation post parthenogenetic activation. It also increased mitochondrial function and ATP levels, reduced intracellular reactive oxygen species, and elevated intracellular GSH levels in both oocytes and embryos. Moreover, FMN significantly decreased autophagy and apoptosis levels in blastocyst cells, potentially via regulation of the Nrf2/Keap1 pathway. This is the first study to report that FMN supplementation benefits the in vitro culture of oocytes and early embryo development, potentially by regulating oxidative stress, mitochondrial function, and autophagy. [ABSTRACT FROM AUTHOR]

Background/Objectives: Skin wrinkles result from a myriad of multifaceted processes involving intrinsic and extrinsic aging. To combat this effect, plant stem cells offer a renewable and eco-friendly source for various industries, including cosmeceuticals. Salvia miltiorrhiza (SM), which contains the bioactive compound Rosmarinic acid (RA) and has been proposed for its anti-wrinkle effect. Methods: In the present study, calli from SM were cultured and Quality by Design (QbD) was implemented to investigate the effect of different types and concentrations of elicitors; jasmonic acid (JA) and salicylic acid (SA). Both raised RA levels yet, jasmonic acid (50 µM) has resulted in the highest yield for RA, at 16 mg/g. A nanofiber patch was prepared and characterized in-vitro by the release percentage, drug content, swelling degree, scanning electron microscope, and surface roughness. Then, the anti-wrinkle effect of the patch was tested in a UV wrinkle-induced mouse model. Results: Interestingly, after treatment, there were visibly fewer wrinkles, and the skin was softer than in the untreated control group. This study suggests that the treatment exerted its effect through the Nrf2/Keap1 pathway, which plays a crucial role in cellular antioxidant protective processes. By activating this pathway through boosting Nrf2 and diminishing Keap1 cellular content, the nanofiber patch enhances the production of antioxidant enzymes, such as superoxide dismutase and glutathione peroxidase, enhancesglutathione, and reduces the skin lipid peroxidation, collectively indicating enhanced skin quality. Conclusions: In conclusion, this study highlights the importance of this formula as an anti-wrinkle treatment, and future clinical studies are recommended to further unveil the potential of this formula. [ABSTRACT FROM AUTHOR]

Artemisia ordosica polysaccharides (AOP) can promote animal growth, improve intestinal morphology, regulate immunity, and enhance antioxidant capacity. To investigate the antioxidant capacity of AOP, three experiments were conducted. (1) Different concentrations of AOP (0, 50, 100, 150, 200, and 250 μg/mL) and 1 µg/mL VA on peripheral blood lymphocytes (PBLs) treated with/without lipopolysaccharides (LPS) were investigated to select the optimum concentration. The results showed that 150 μg/mL AOP had significant antioxidation activity. (2) The PBLs was randomly divided into eight treatments with six replicates, namely CON, AOP, LPS, ML385 (Nrf2 inhibitor), AOP + LPS, AOP + ML385, LPS + ML385 and LPS + ML385 + AOP. The results showed that under a normal condition or stress condition, AOP presented antioxidation activity via upregulating Nrf2/Keap1 pathway-related gene expression. (3) The PBLs was randomly divided into eight treatments with six replicates, namely CON, AOP, LPS, PDTC (NF-κB inhibitor), AOP + LPS, AOP + PDTC, LPS + PDTC and LPS + PDTC + AOP. The results showed that under a normal condition, AOP presented antioxidation activity via increasing TLR4/NF-κB pathway-related gene expression; under a stress condition, AOP alleviated oxidative damage caused by LPS via suppressing TLR4/NF-κB pathway-related gene expression. [ABSTRACT FROM AUTHOR]

Increasing evidence has demonstrated that oxidative stress impairs oocyte maturation and embryonic development. Conventionally, antioxidants have been applied in vitro systems to improve oocyte maturation and blastocyst rates. Formononetin (FMN) is a flavonoid that has been shown to have various pharmacological effects, including antioxidants. In this study, we delved into the impact of FMN, acting as an antioxidant, on the in vitro development of oocytes and blastocysts within the culture system. FMN supplementation at 0.5 μM enhanced the rate of first polar body extrusion and blastocyst formation post parthenogenetic activation. It also increased mitochondrial function and ATP levels, reduced intracellular reactive oxygen species, and elevated intracellular GSH levels in both oocytes and embryos. Moreover, FMN significantly decreased autophagy and apoptosis levels in blastocyst cells, potentially via regulation of the Nrf2/Keap1 pathway. This is the first study to report that FMN supplementation benefits the in vitro culture of oocytes and early embryo development, potentially by regulating oxidative stress, mitochondrial function, and autophagy.

Diabetic retinopathy is a secondary microvascular complication of diabetes mellitus. This disease progresses from two stages, non-proliferative and proliferative diabetic retinopathy, the latter characterized by retinal abnormal angiogenesis. Pharmacological management of retinal angiogenesis employs expensive and invasive intravitreal injections of biologic drugs (anti-vascular endothelial growth factor agents). To search small molecules able to act as anti-angiogenic agents, we focused our study on axitinib, which is a tyrosine kinase inhibitor and represents the second line treatment for renal cell carcinoma. Axitinib is an inhibitor of vascular endothelial growth factor receptors, and among the others tyrosine kinase inhibitors (sunitinib and sorafenib) is the most selective towards vascular endothelial growth factor receptors 1 and 2. Besides the wellknown anti-angiogenic and immune-modulatory functions, we hereby explored the polypharmacological profile of axitinib, through a bioinformatic/molecular modeling approach and in vitro models of diabetic retinopathy. We showed the anti-angiogenic activity of axitinib in two different in vitro models of diabetic retinopathy, by challenging retinal endothelial cells with high glucose concentration (fluctuating and non-fluctuating). We found that axitinib, along with inhibition of vascular endothelial growth factor receptors 1 (1.82 ± 0.10; 0.54 ± 0.13, phosphorylated protein levels in fluctuating high glucose vs. axitinib 1 μM, respectively) and vascular endothelial growth factor receptors 2 (2.38 ± 0.21; 0.98 ± 0.20, phosphorylated protein levels in fluctuating high glucose vs. axitinib 1 μM, respectively), was able to significantly reduce (p < 0.05) the expression of Nrf2 (1.43 ± 0.04; 0.85 ± 0.01, protein levels in fluctuating high glucose vs. axitinib 1 μM, respectively) in retinal endothelial cells exposed to high glucose, through predicted Keap1 interaction and activation of melanocortin receptor 1. Furthermore, axitinib treatment significantly (p < 0.05) decreased reactive oxygen species production (0.90 ± 0.10; 0.44 ± 0.06, fluorescence units in high glucose vs. axitinib 1 μM, respectively) and inhibited ERK pathway (1.64 ± 0.09; 0.73 ± 0.06, phosphorylated protein levels in fluctuating high glucose vs. axitinib 1 μM, respectively) in HRECs exposed to high glucose. The obtained results about the emerging polypharmacological profile support the hypothesis that axitinib could be a valid candidate to handle diabetic retinopathy, with ancillary mechanisms of action. [ABSTRACT FROM AUTHOR]

Abstract Background & objective : While oxidative stress is the key player driving diabetic nephropathy (DN), firm glycemic control remains the pillar prophylactic measure. Purslane was extensively described as a potent hypoglycemic and hypolipidemic agent owing to its rich content of antioxidants. Therefore, this report aimed to assess the renoprotective potentials of methanol (MO) and methylene chloride (MC) fixed oil extracts of purslane seeds in a diabetic nephropathy (DN) model. Methods Purslane seeds were extracted using absolute methanol and methylene chloride, and type-1 diabetes was induced with a single 55 mg/kg dose of Streptozotocin (STZ) dissolved in 100 mmol/L citrate buffer (pH 4.5), and then diabetic animals were received MO, MC, for 42 consecutive days to compare their antidiabetic effect relative to the reference drug “Losartan”. Renal functions and DN biomarkers were weekly assessed, and the relative expression of different oxido-inflammatory mediators was quantified in diabetic kidneys by RT-PCR. Data were statistically analyzed using GraphPad Prism 9.0.2. Results The oral administration of MO and MC extracts (250 mg/kg/day) significantly ameliorated the body weight loss (P

Background & objective: : While oxidative stress is the key player driving diabetic nephropathy (DN), firm glycemic control remains the pillar prophylactic measure. Purslane was extensively described as a potent hypoglycemic and hypolipidemic agent owing to its rich content of antioxidants. Therefore, this report aimed to assess the renoprotective potentials of methanol (MO) and methylene chloride (MC) fixed oil extracts of purslane seeds in a diabetic nephropathy (DN) model. Methods: Purslane seeds were extracted using absolute methanol and methylene chloride, and type-1 diabetes was induced with a single 55 mg/kg dose of Streptozotocin (STZ) dissolved in 100 mmol/L citrate buffer (pH 4.5), and then diabetic animals were received MO, MC, for 42 consecutive days to compare their antidiabetic effect relative to the reference drug "Losartan". Renal functions and DN biomarkers were weekly assessed, and the relative expression of different oxido-inflammatory mediators was quantified in diabetic kidneys by RT-PCR. Data were statistically analyzed using GraphPad Prism 9.0.2. Results: The oral administration of MO and MC extracts (250 mg/kg/day) significantly ameliorated the body weight loss (P < 0.0001 / each), fasting blood glucose levels (FBG) (P < 0.0001 / each), urine volume (P < 0.0001 / each), as well as serum creatinine (P < 0.0001 / each), uric acid (P = 0.0022, 0.0052), and blood urea nitrogen (BUN) (P = 0.0265, 0.0338); respectively, compared with the untreated diabetic rats. In addition, both extracts restored the effectuality of antioxidative machinery in diabetic kidneys as indicated by a significant reduction of ROS accumulation and lipid peroxidation; higher GSH content, and promoted activity of glutathione reductase and superoxide dismutase antioxidant enzymes (P < 0.0001 / each). Histologically, both extracts alleviated the DN-structural alterations including the glomerular congestion and tubular degeneration, with MC-treated kidneys showing near to normal architecture. The transcription profiles of all treated kidneys revealed a significantly downregulated expression of TNF-α, IL-6, Keap1 and NF-κB genes, concomitant with a significant upregulation of SDF-1, IL-10, Nrf2, HO-1, and PPARγ gene expression (P < 0.0001 / all). Conclusion: These findings highlight the remarkable DN-prophylactic potentials of purslane extracts mediated by neutralizing the hyperglycemia-induced ROS accumulation, and circumventing the downstream inflammatory cascades, surpassing the reference angiotensin receptor blocker; i.e. Losartan. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy is a secondary microvascular complication of diabetes mellitus. This disease progresses from two stages, non-proliferative and proliferative diabetic retinopathy, the latter characterized by retinal abnormal angiogenesis. Pharmacological management of retinal angiogenesis employs expensive and invasive intravitreal injections of biologic drugs (anti-vascular endothelial growth factor agents). To search small molecules able to act as anti-angiogenic agents, we focused our study on axitinib, which is a tyrosine kinase inhibitor and represents the second line treatment for renal cell carcinoma. Axitinib is an inhibitor of vascular endothelial growth factor receptors, and among the others tyrosine kinase inhibitors (sunitinib and sorafenib) is the most selective towards vascular endothelial growth factor receptors 1 and 2. Besides the well-known anti-angiogenic and immune-modulatory functions, we hereby explored the polypharmacological profile of axitinib, through a bioinformatic/molecular modeling approach and in vitro models of diabetic retinopathy. We showed the anti-angiogenic activity of axitinib in two different in vitro models of diabetic retinopathy, by challenging retinal endothelial cells with high glucose concentration (fluctuating and non-fluctuating). We found that axitinib, along with inhibition of vascular endothelial growth factor receptors 1 (1.82 ± 0.10; 0.54 ± 0.13, phosphorylated protein levels in fluctuating high glucose vs. axitinib 1 µM, respectively) and vascular endothelial growth factor receptors 2 (2.38 ± 0.21; 0.98 ± 0.20, phosphorylated protein levels in fluctuating high glucose vs. axitinib 1 µM, respectively), was able to significantly reduce (p < 0.05) the expression of Nrf2 (1.43 ± 0.04; 0.85 ± 0.01, protein levels in fluctuating high glucose vs. axitinib 1 µM, respectively) in retinal endothelial cells exposed to high glucose, through predicted Keap1 interaction and activation of melanocortin receptor 1. Furthermore, axitinib treatment significantly (p < 0.05) decreased reactive oxygen species production (0.90 ± 0.10; 0.44 ± 0.06, fluorescence units in high glucose vs. axitinib 1 µM, respectively) and inhibited ERK pathway (1.64 ± 0.09; 0.73 ± 0.06, phosphorylated protein levels in fluctuating high glucose vs. axitinib 1 µM, respectively) in HRECs exposed to high glucose. The obtained results about the emerging polypharmacological profile support the hypothesis that axitinib could be a valid candidate to handle diabetic retinopathy, with ancillary mechanisms of action.

Artemisia ordosica polysaccharides (AOP) can promote animal growth, improve intestinal morphology, regulate immunity, and enhance antioxidant capacity. To investigate the antioxidant capacity of AOP, three experiments were conducted. (1) Different concentrations of AOP (0, 50, 100, 150, 200, and 250 μg/mL) and 1 µg/mL VA on peripheral blood lymphocytes (PBLs) treated with/without lipopolysaccharides (LPS) were investigated to select the optimum concentration. The results showed that 150 μg/mL AOP had significant antioxidation activity. (2) The PBLs was randomly divided into eight treatments with six replicates, namely CON, AOP, LPS, ML385 (Nrf2 inhibitor), AOP + LPS, AOP + ML385, LPS + ML385 and LPS + ML385 + AOP. The results showed that under a normal condition or stress condition, AOP presented antioxidation activity via upregulating Nrf2/Keap1 pathway-related gene expression. (3) The PBLs was randomly divided into eight treatments with six replicates, namely CON, AOP, LPS, PDTC (NF-κB inhibitor), AOP + LPS, AOP + PDTC, LPS + PDTC and LPS + PDTC + AOP. The results showed that under a normal condition, AOP presented antioxidation activity via increasing TLR4/NF-κB pathway-related gene expression; under a stress condition, AOP alleviated oxidative damage caused by LPS via suppressing TLR4/NF-κB pathway-related gene expression.

The brain has a high metabolism rate that may generate reactive oxygen and nitrogen species. Consequently, nerve cells require highly efficient antioxidant defenses in order to prevent a condition of deleterious oxidative stress. This is particularly relevant in the hippocampus, a highly complex cerebral area involved in processing superior cognitive functions. Most current evidence points to hippocampal oxidative damage as a causal effect for neurodegenerative disorders, especially Alzheimer's disease. Nuclear factor erythroid-2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2/Keap1) is a master key for the transcriptional regulation of antioxidant and detoxifying systems. It is ubiquitously expressed in brain areas, mainly supporting glial cells. In the present study, we have analyzed the relationships between Nrf2 and Keap1 isoforms in hippocampal tissue in response to aging and dietary long-chain polyunsaturated fatty acids (LCPUFA) supplementation. The possible involvement of lipoxidative and nitrosative by-products in the dynamics of the Nrf2/Keap1 complex was examined though determination of protein adducts, namely malondialdehyde (MDA), 4-hydroxynonenal (HNE), and 3-nitro-tyrosine (NTyr) under basal conditions. The results were correlated to the expression of target proteins heme-oxygenase-1 (HO-1) and glutathione peroxidase 4 (GPx4), whose expressions are known to be regulated by Nrf2/Keap1 signaling activation. All variables in this study were obtained simultaneously from the same preparations, allowing multivariate approaches. The results demonstrate a complex modification of the protein expression patterns together with the formation of adducts in response to aging and diet supplementation. Both parameters exhibited a strong interaction. Noticeably, LCPUFA supplementation to aged animals restored the Nrf2/Keap1/target protein patterns to the status observed in young animals, therefore driving a "rejuvenation" of hippocampal antioxidant defense. [ABSTRACT FROM AUTHOR]

Questions about which reactive oxygen species (ROS) or reactive nitrogen species (RNS) can escape from the mitochondria and activate signals must be addressed. In this study, two parameters, the calculated dipole moment (debye, D) and permeability coefficient (Pm) (cm s−1), are listed for hydrogen peroxide (H2O2), hydroxyl radical (•OH), superoxide (O2•−), hydroperoxyl radical (HO2•), nitric oxide (•NO), nitrogen dioxide (•NO2), peroxynitrite (ONOO−), and peroxynitrous acid (ONOOH) in comparison to those for water (H2O). O2•− is generated from the mitochondrial electron transport chain (ETC), and several other ROS and RNS can be generated subsequently. The candidates which pass through the mitochondrial membrane include ROS with a small number of dipoles, i.e., H2O2, HO2•, ONOOH, •OH, and •NO. The results show that the dipole moment of •NO2 is 0.35 D, indicating permeability; however, •NO2 can be eliminated quickly. The dipole moments of •OH (1.67 D) and ONOOH (1.77 D) indicate that they might be permeable. This study also suggests that the mitochondria play a central role in protecting against further oxidative stress in cells. The amounts, the long half-life, the diffusion distance, the Pm, the one-electron reduction potential, the pKa, and the rate constants for the reaction with ascorbate and glutathione are listed for various ROS/RNS, •OH, singlet oxygen (1O2), H2O2, O2•−, HO2•, •NO, •NO2, ONOO−, and ONOOH, and compared with those for H2O and oxygen (O2). Molecules with negative electrical charges cannot directly diffuse through the phospholipid bilayer of the mitochondrial membranes. Short-lived molecules, such as •OH, would be difficult to contribute to intracellular signaling. Finally, HO2• and ONOOH were selected as candidates for the ROS/RNS that pass through the mitochondrial membrane. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of maternal selenium-enriched yeast (SeY) supplementation during late gestation and lactation on sow performance, transfer of selenium (Se) and redox status, and gut microbiota community, as well as on the gut health of offspring. Seventy pregnant sows on day 85 of gestation were randomly allocated to the following two treatments: (1) sows who were fed a basal diet (basal diet contained 0.3 mg/kg Se as Na2SeO3, n = 35); (2) and sows who were fed a SeY-supplemented diet (basal diet with 0.2 mg/kg Se as SeY, n = 35). The offspring piglets were only cross-fostered within the group on day 3 of lactation (L3) according to the pig farm epidemic prevention policy. The plasma, milk, and feces samples from 10 sows, as well as plasma and intestinal samples per treatment, were collected on L1 and L21, respectively. Our results showed that maternal SeY supplementation increased the first week average weight and ADG of piglets (p < 0.05). Compared with the CON group, the SeY supplementation increased the Se content in the plasma and milk of sows and the plasma of piglets on L1 and L21 (p < 0.05). In addition, in sows, the levels of fat in the milk on L21, the level of IgA, T-AOC, and GSH-Px in the plasma on L21, and the level of T-AOC and GSH-Px in the colostrum were increased, while the MDA content was decreased in the plasma on L1 and in the colostrum and milk on L14 (p < 0.05). In the piglet plasma, the levels of IgA on L1 and L21, GSH-Px on L1, and GSH on L21 were increased, while the MDA content was decreased on L1 (p < 0.05). Maternal SeY supplementation up-regulated the small intestinal protein abundances of MUC1, E-cadherin, ZO-1, occludin, and claudin and activated the Nrf2/Keap1 signaling pathway in weaned offspring piglets. The 16S rRNA sequencing results showed that fecal microbiota had distinct separations during lactation, and the relative abundances of unclassified_f_Lachnospiraceae, Prevotaceae_UCG-001, and Lachnospiraceae_NK4A136_group were increased on L1. Collectively, the current findings suggest that maternal SeY supplementation during late gestation and lactation could improve the piglet's growth performance, Se status, antioxidant capacity and immunoglobulins transfer at the first week of lactation, as well as alter the fecal microbiota composition by increasing antioxidative-related and SCFA-producing microbiota in sows. These changes contributed to enhancing the small intestinal barrier function and activating the Nrf2/Keap1 pathway in offspring. [ABSTRACT FROM AUTHOR]

Organ preservation protocols are commonly used as first line therapy for advanced laryngeal cancer. Recurrence thereafter is associated with poor survival. The aim of this study is to identify genetic alterations associated with survival among patients with recurrent laryngeal cancer undergoing salvage laryngectomy. Sixty-two patients were sequenced using a targeted panel, of which twenty-two also underwent transcriptome sequencing. Alterations were grouped based on biologic pathways and survival outcomes were assessed using Kaplan-Meier analysis and multivariate cox regression. Select pathways were evaluated against The Cancer Genome Atlas (TCGA) data. Patients with mutations in the Oxidation pathway had significantly worse five-year disease specific survival (1% vs. 76%, p = 0.02), while mutations in the HN-Immunity pathway were associated with improved five-year disease specific survival (100% vs. 62%, p = 0.02). Multivariate analysis showed mutations in the Oxidation pathway remained an independent predictor of disease specific survival (HR 3.2, 95% CI 1.1-9.2, p = 0.03). Transcriptome analysis of recurrent tumors demonstrated that alterations in the Oxidation pathway were associated a positive Ragnum hypoxia signature score, consistent with enhanced pathway activity. Further, TCGA analyses demonstrated the prognostic value of oxidation pathway alterations in previously untreated disease. Alterations in the Oxidation pathway are associated with survival among patients with recurrent laryngeal cancer. These prognostic genetic biomarkers may inform precision medicine protocols and identify putatively targetable pathways to improve survival in this cohort.

Permanent pancreatic islet cell destruction occurs in type 1 diabetes mellitus (T1DM) through the infiltration of inflammatory cells and cytokines. Loss of β-cell integrity secondary to oxidation leads to an inability to appropriately synthesize and secrete insulin. Allogenic islet cell transplantation (ICT) has risen as a therapeutic option to mitigate problematic hypoglycemia. Nevertheless, during the process of transplantation, islet cells are exposed to oxidatively caustic conditions that severely decrease the islet cell yield. Islet cells are at a baseline disadvantage to sustain themselves during times of metabolic stress as they lack a robust anti-oxidant defense system, glycogen stores, and vascularity. The Nrf2/Keap1 system is a master regulator of antioxidant genes that has garnered attention as pharmacologic activators have shown a protective response and a low side effect profile. Herein, we present the most recently studied Nrf2/Keap1 activators in pancreas for application in ICT: Dh404, dimethyl fumarate (DMF), and epigallocatechin gallate (EGCG). Furthermore, we discuss that Nrf2/Keap1 is a potential target to ameliorate oxidative stress at every step of the Edmonton Protocol.

Oxidative stress plays a significant role in the development of cancer. Inhibiting the protein-protein interaction (PPI) between Keap1 and Nrf2 offers a promising strategy to activate the Nrf2 antioxidant pathway, which is normally suppressed by the binding of Keap1 to Nrf2. This study aimed to identify natural compounds capable of targeting the kelch domain of KEAP1 using structure-based drug design methods. A pharmacophore model was constructed based on the KEAP1-inhibitor complex, leading to the selection of 6178 compounds that matched the model. Subsequently, docking and MM/GBSA analyses were conducted, resulting in the identification of 10 compounds with superior binding energies compared to the reference compound. From these, three compounds (ZINC000002123788, ZINC000002111341, and ZINC000002125904) were chosen for further investigation. Ligand–residue interaction analysis revealed specific interactions between these compounds and key residues, indicating their stability within the binding site. ADMET analysis confirmed that the selected compounds possessed desirable drug-like properties. Furthermore, molecular dynamics simulations were performed, demonstrating the stability of the ligand–protein complexes over a 100 ns duration. These findings underscore the potential of the selected natural compounds as agents targeting KEAP1 and provide valuable insights for future experimental studies. [ABSTRACT FROM AUTHOR]

Placentation is a key and tightly regulated process that ensures the normal development of the placenta and fetal growth. Preeclampsia (PE) is a hypertensive pregnancy-related disorder involving about 5–8% of all pregnancies and clinically characterized by de novo maternal hypertension and proteinuria. In addition, PE pregnancies are also characterized by increased oxidative stress and inflammation. The NRF2/KEAP1 signaling pathway plays an important role in protecting cells against oxidative damage due to increased reactive oxygen species (ROS) levels. ROS activate NRF2, allowing its binding to the antioxidant response element (ARE) region present in the promoter of several antioxidant genes such as heme oxygenase, catalase, glutathione peroxidase and superoxide dismutase that neutralize ROS, protecting cells against oxidative stress damages. In this review, we analyze the current literature regarding the role of the NRF2/KEAP1 pathway in preeclamptic pregnancies, discussing the main cellular modulators of this pathway. Moreover, we also discuss the main natural and synthetic compounds that can regulate this pathway in in vivo and in vitro models. [ABSTRACT FROM AUTHOR]

Organ preservation protocols are commonly used as first line therapy for advanced laryngeal cancer. Recurrence thereafter is associated with poor survival. The aim of this study is to identify genetic alterations associated with survival among patients with recurrent laryngeal cancer undergoing salvage laryngectomy. Sixty-two patients were sequenced using a targeted panel, of which twenty-two also underwent transcriptome sequencing. Alterations were grouped based on biologic pathways and survival outcomes were assessed using Kaplan-Meier analysis and multivariate cox regression. Select pathways were evaluated against The Cancer Genome Atlas (TCGA) data. Patients with mutations in the Oxidation pathway had significantly worse five-year disease specific survival (1% vs. 76%, p = 0.02), while mutations in the HN-Immunity pathway were associated with improved five-year disease specific survival (100% vs. 62%, p = 0.02). Multivariate analysis showed mutations in the Oxidation pathway remained an independent predictor of disease specific survival (HR 3.2, 95% CI 1.1-9.2, p = 0.03). Transcriptome analysis of recurrent tumors demonstrated that alterations in the Oxidation pathway were associated a positive Ragnum hypoxia signature score, consistent with enhanced pathway activity. Further, TCGA analyses demonstrated the prognostic value of oxidation pathway alterations in previously untreated disease. Alterations in the Oxidation pathway are associated with survival among patients with recurrent laryngeal cancer. These prognostic genetic biomarkers may inform precision medicine protocols and identify putatively targetable pathways to improve survival in this cohort.

It has been known that reactive oxygen species (ROS) are generated from the mitochondrial electron transport chain (ETC). Majima et al. proved that mitochondrial ROS (mtROS) caused apoptosis for the first time in 1998 (Majima et al. J Biol Chem, 1998). It is speculated that mtROS can move out of the mitochondria and initiate cellular signals in the nucleus. This paper aims to prove this phenomenon by assessing the change in the amount of manganese superoxide dismutase (MnSOD) by MnSOD transfection. Two cell lines of the same genetic background, of which generation of mtROS are different, i.e., the mtROS are more produced in RGK1, than in that of RGM1, were compared to analyze the cellular signals. The results of immunocytochemistry staining showed increase of Nrf2, Keap1, HO-1 and 2, MnSOD, GCL, GST, NQO1, GATA1, GATA3, GATA4, and GATA5 in RGK1 compared to those in RGM1. Transfection of human MnSOD in RGK1 cells showed a decrease of those signal proteins, suggesting mtROS play a role in cellular signals in nucleus. [ABSTRACT FROM AUTHOR]

The brain has a high metabolism rate that may generate reactive oxygen and nitrogen species. Consequently, nerve cells require highly efficient antioxidant defenses in order to prevent a condition of deleterious oxidative stress. This is particularly relevant in the hippocampus, a highly complex cerebral area involved in processing superior cognitive functions. Most current evidence points to hippocampal oxidative damage as a causal effect for neurodegenerative disorders, especially Alzheimer’s disease. Nuclear factor erythroid-2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2/Keap1) is a master key for the transcriptional regulation of antioxidant and detoxifying systems. It is ubiquitously expressed in brain areas, mainly supporting glial cells. In the present study, we have analyzed the relationships between Nrf2 and Keap1 isoforms in hippocampal tissue in response to aging and dietary long-chain polyunsaturated fatty acids (LCPUFA) supplementation. The possible involvement of lipoxidative and nitrosative by-products in the dynamics of the Nrf2/Keap1 complex was examined though determination of protein adducts, namely malondialdehyde (MDA), 4-hydroxynonenal (HNE), and 3-nitro-tyrosine (NTyr) under basal conditions. The results were correlated to the expression of target proteins heme-oxygenase-1 (HO-1) and glutathione peroxidase 4 (GPx4), whose expressions are known to be regulated by Nrf2/Keap1 signaling activation. All variables in this study were obtained simultaneously from the same preparations, allowing multivariate approaches. The results demonstrate a complex modification of the protein expression patterns together with the formation of adducts in response to aging and diet supplementation. Both parameters exhibited a strong interaction. Noticeably, LCPUFA supplementation to aged animals restored the Nrf2/Keap1/target protein patterns to the status observed in young animals, therefore driving a “rejuvenation” of hippocampal antioxidant defense.

This study evaluated the effects of maternal selenium-enriched yeast (SeY) supplementation during late gestation and lactation on sow performance, transfer of selenium (Se) and redox status, and gut microbiota community, as well as on the gut health of offspring. Seventy pregnant sows on day 85 of gestation were randomly allocated to the following two treatments: (1) sows who were fed a basal diet (basal diet contained 0.3 mg/kg Se as Na2SeO3, n = 35); (2) and sows who were fed a SeY-supplemented diet (basal diet with 0.2 mg/kg Se as SeY, n = 35). The offspring piglets were only cross-fostered within the group on day 3 of lactation (L3) according to the pig farm epidemic prevention policy. The plasma, milk, and feces samples from 10 sows, as well as plasma and intestinal samples per treatment, were collected on L1 and L21, respectively. Our results showed that maternal SeY supplementation increased the first week average weight and ADG of piglets (p < 0.05). Compared with the CON group, the SeY supplementation increased the Se content in the plasma and milk of sows and the plasma of piglets on L1 and L21 (p < 0.05). In addition, in sows, the levels of fat in the milk on L21, the level of IgA, T-AOC, and GSH-Px in the plasma on L21, and the level of T-AOC and GSH-Px in the colostrum were increased, while the MDA content was decreased in the plasma on L1 and in the colostrum and milk on L14 (p < 0.05). In the piglet plasma, the levels of IgA on L1 and L21, GSH-Px on L1, and GSH on L21 were increased, while the MDA content was decreased on L1 (p < 0.05). Maternal SeY supplementation up-regulated the small intestinal protein abundances of MUC1, E-cadherin, ZO-1, occludin, and claudin and activated the Nrf2/Keap1 signaling pathway in weaned offspring piglets. The 16S rRNA sequencing results showed that fecal microbiota had distinct separations during lactation, and the relative abundances of unclassified_f_Lachnospiraceae, Prevotaceae_UCG-001, and Lachnospiraceae_NK4A136_group were increased on L1. Collectively, the current findings suggest that maternal SeY supplementation during late gestation and lactation could improve the piglet’s growth performance, Se status, antioxidant capacity and immunoglobulins transfer at the first week of lactation, as well as alter the fecal microbiota composition by increasing antioxidative-related and SCFA-producing microbiota in sows. These changes contributed to enhancing the small intestinal barrier function and activating the Nrf2/Keap1 pathway in offspring.

Abstract Background Adenoid cystic carcinoma (ACC) is one of the most common malignant salivary gland tumors. Moreover, the unique biological characteristics and complex structures of ACC contribute to its poor survival rates. Recently, proteasome inhibitors have been shown to elicit satisfactory therapeutic effects in the treatment of certain solid tumors, but few studies have been implemented to investigate the effects of proteasome inhibitor therapy for ACC. Methods In this present study, cell counting kit-8 assay and flow cytometry assay were performed to examine the effects of proteasome inhibitor (MG132) on cell viability and apoptosis. We applied western blot and immunofluorescence staining to explore the expression of the Nrf2/Keap1 signaling pathway and P62, additionally Nrf2 inhibitor (ML385) was utilized to evaluate the role of Nrf2/Keap1 signaling pathway in MG132-induced cell apoptosis. Results Our data indicated that MG132 significantly suppressed the growth of ACC-83 cells(MG132 10µM P = 0.0046; 40µM P = 0.0033; 70µM P = 0.0007 versus control) and induced apoptosis (MG132 10µM P = 0.0458; 40µM P = 0.0018; 70µM P = 0.0087 versus control). The application of MG132 induced the up-regulation of Nrf2/Keap1 signaling pathway. Furthermore, inhibition of Nrf2 attenuated the therapeutic effects of MG132 for ACC (both ML385 + MG132 10µM P = 0.0013; 40µM P = 0.0057; 70µM P = 0.0003 versus MG132). P

Oxidative stress has impacts on the KRas and Nrf2/Keap1 pathways, which have multiple interactions with each other and play important roles in colorectal cancer (CRC). This study investigated the expressions of proteins in the KRas and Nrf2/Keap1 pathways and their associations with clinicopathological features in CRC. The protein levels of Nrf2, Keap1, Bach1, p62, HO1, KRas, Erk, Raf1 and PI3K in both the tumour and normal tissues of 60 CRC subjects were determined by Western blot and their T/N (tumour/normal tissue) ratios were correlated with clinicopathological features. The T/N ratios of proteins in the KRas and Nrf2/Keap1 pathways had correlation patterns and proximity profiles in cluster dendrograms different in CRC with different status of lymphovascular invasion (LVI) or lymph node/distant metastases. The Keap1 protein T/N ratio was a significant predictor (odd ratio: 2.24; 95% confidence interval: 1.26 − 4.38) of LVI, which in turn predicted metastases (11.0; 3.49 − 39.8). The interactions between the KRas and Nrf2/Keap1 pathways may be affected differently by LVI and metastases, and the protein T/N ratio of Keap1 may be helpful for predicting LVI in CRC. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the anti-neuropathic pain activity and its underlying molecular mechanism of Ajugarin-I (Aju-I) in a rat model of diabetic neuropathic pain. The rats were given a single injection of 60 mg/kg of streptozotocin (STZ) intraperitoneally (i.p.) to induce diabetic neuropathic pain. After two weeks, rats were given Aju-I (1 and 5 mg/kg/day) i.p. for four consecutive weeks. The results demonstrated that in diabetic rats, treatment with Aju-I decreased STZ-induced hyperglycemia. It reduced the pain hypersensitivity (mechanical, thermal, and cold nociception) caused by STZ. It effectively restored STZ-associated pathological changes in the pancreas. In the sciatic nerve and spinal cord, it attenuated STZ-associated histopathological alterations and DNA damage. It suppressed oxidative stress by increasing the expression of nuclear factor-erythroid factor 2-related factor 2 (Nrf2), thioredoxin (Trx), and heme oxygenase (HO-1), but decreasing the immunoreactivity of Kelch-like ECH-associated protein 1 (Keap1). Additionally, TRPV1 (transient receptor potential vanilloid 1) and TRPM8 (transient receptor potential melastatin 8) expression levels were considerably reduced by Aju-I treatment. It enhanced antioxidant levels and suppressed inflammatory cytokines production. Taken together, this research suggests that Aju-I treatment reduces pain behaviors in the STZ model of diabetic neuropathy via modulating Nrf2/Keap-1/HO-1 signaling and TRPV1/TRPM8 nociceptors.

The present study was conducted to investigate the protective effects of selenium on the oxidative damage of kidney cells (CIK) caused by nitrite exposure in grass carp (Ctenopharyngodon idella). Cells were pre-incubated by Na2SeO3 (10 μmol/L) for 12 h and then exposed to NaNO2 (25 mg/L) for 24 h, the cell viability, apoptosis, gene expression, and antioxidant enzyme activity were assayed. The results show that nitrite reduced cell viability and induced apoptosis, and the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) as well as the sod, cat, and gpx genes reduced (p < 0.05), while the intracellular calcium ion concentration increased (p < 0.05). Interestingly, selenium treatment significantly alleviated the nitrite induced changes in cell growth, apoptosis, and calcium influx. The cell viability after low-concentration selenium treatment is higher than that of normal cells (p < 0.05). CIK cells were pre-incubated with Na2SeO3 and then exposed to NaNO2, the antioxidant indicators could be maintained at normal levels. And compared with nitrite exposure, intracellular calcium ion concentration and apoptotic rate of selenium-incubated still decreased. The expressions of Nrf2 and Keap1 genes increased significantly in CIK cells treated with sodium selenite for 12 h, and the same trend as the enzyme activities of this group. The results show that the supplement of selenium can enhance the cell's resistance to sodium nitrite exposure to a certain extent, by alleviating the antioxidant imbalance, high apoptosis rate, and intracellular calcium ion disturbance caused by nitrite exposure. And the Nrf2-Keap1 pathway may play an important role in the process. [ABSTRACT FROM AUTHOR]

Background: Adenoid cystic carcinoma (ACC) is one of the most common malignant salivary gland tumors. Moreover, the unique biological characteristics and complex structures of ACC contribute to its poor survival rates. Recently, proteasome inhibitors have been shown to elicit satisfactory therapeutic effects in the treatment of certain solid tumors, but few studies have been implemented to investigate the effects of proteasome inhibitor therapy for ACC. Methods: In this present study, cell counting kit-8 assay and flow cytometry assay were performed to examine the effects of proteasome inhibitor (MG132) on cell viability and apoptosis. We applied western blot and immunofluorescence staining to explore the expression of the Nrf2/Keap1 signaling pathway and P62, additionally Nrf2 inhibitor (ML385) was utilized to evaluate the role of Nrf2/Keap1 signaling pathway in MG132-induced cell apoptosis. Results: Our data indicated that MG132 significantly suppressed the growth of ACC-83 cells(MG132 10µM P = 0.0046; 40µM P = 0.0033; 70µM P = 0.0007 versus control) and induced apoptosis (MG132 10µM P = 0.0458; 40µM P = 0.0018; 70µM P = 0.0087 versus control). The application of MG132 induced the up-regulation of Nrf2/Keap1 signaling pathway. Furthermore, inhibition of Nrf2 attenuated the therapeutic effects of MG132 for ACC (both ML385 + MG132 10µM P = 0.0013; 40µM P = 0.0057; 70µM P = 0.0003 versus MG132). P < 0.05 was considered statistically significant. Conclusions: Our results revealed that proteasome inhibitors MG132 could inhibit the cell viability and induce the apoptosis of ACC through Nrf2/Keap1 signaling pathway. [ABSTRACT FROM AUTHOR]

To investigate whether growth hormone (GH) can improve oxidative stress (OS) by affecting) /nuclear factor erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1) in women of advanced age undergoing in vitro fertilization (IVF). This retrospective study enrolled 141 patients, including 65 aged C patients (patients not treated with GH) and 76 aged GH patients (patients treated with GH). The outcomes included IVF-ET results, OS markers in follicle fluid (FF) and Nrf2 and Keap1 mRNA and protein expressions in granulosa cells (GCs). The results showed that GH improved the available blastocyst (p=.047) and implantation rate (p=.043) in women of advanced age undergoing IVF. The malondialdehyde (MDA) content of FF was significantly higher in the aged-C group than in the aged-GH group (p=.013). The antioxidant enzyme activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-px) and catalase (CAT) were significantly lower in the aged-C group than in the aged-GH group (p=.000, p=.049, p=.012 respectively). Nrf2 mRNA and protein expression was significantly higher and Keap1 mRNA and protein expression was lower in the aged-GH group than in the aged-C group (p=.000, p=.000 respectively). The study showed that GH improved embryo quality and implantation rate and alleviated OS in FF, which may be related to Nrf2/Keap1. [ABSTRACT FROM AUTHOR]

Glycyrrhetinic acid (GA), the active metabolic product of Glycyrrhizin (GL) that is the main ingredient of licorice, was reported to protect against α-naphthylisothiocyanate (ANIT)- induced cholestasis. However, its protective mechanism remains unclear. In our work, the cholestatic liver injury in mice was caused by ANIT and GA was used for the treatment. We assessed cholestatic liver injury specific indexes, histopathological changes, bile acid transporters, inflammation and apoptosis. The results of liver biochemical index and histopathological examination showed that GA markedly attenuated ANIT-induced liver injury. Mechanism research suggested that GA could activate the expression of farnesoid x receptor (FXR) and its downstream bile acids transporters Na+/taurocholate co-transporting polypeptide (NTCP), bile salt export pump (BSEP) and multidrug resistance-associated protein 2 (MRP2), as well as the nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream proteins MRP3, MRP4. These transporters play a vital role in mediating bile acid homeostasis in hepatocytes. Moreover, GA could significantly inhibit the ANIT-induced activation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) inflammatory pathway and the increase of tumor necrosis factor-α (TNF-α) concentration in serum. Also, GA protected against ANIT-induced mitochondrial apoptosis by regulating the expression of Bcl-2, Bax, cleaved caspase 3 and cleaved caspase 9. In conclusion, GA alleviates the hepatotoxicity caused by ANIT by regulating bile acids transporters, inflammation and apoptosis, which suggests that GA may be a potential therapeutic agent for cholestasis.

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Glycyrrhetinic acid (GA), the active metabolic product of Glycyrrhizin (GL) that is the main ingredient of licorice, was reported to protect against α-naphthylisothiocyanate (ANIT)- induced cholestasis. However, its protective mechanism remains unclear. In our work, the cholestatic liver injury in mice was caused by ANIT and GA was used for the treatment. We assessed cholestatic liver injury specific indexes, histopathological changes, bile acid transporters, inflammation and apoptosis. The results of liver biochemical index and histopathological examination showed that GA markedly attenuated ANIT-induced liver injury. Mechanism research suggested that GA could activate the expression of farnesoid x receptor (FXR) and its downstream bile acids transporters Na+/taurocholate co-transporting polypeptide (NTCP), bile salt export pump (BSEP) and multidrug resistance-associated protein 2 (MRP2), as well as the nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream proteins MRP3, MRP4. These transporters play a vital role in mediating bile acid homeostasis in hepatocytes. Moreover, GA could significantly inhibit the ANIT-induced activation of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) inflammatory pathway and the increase of tumor necrosis factor-α (TNF-α) concentration in serum. Also, GA protected against ANIT-induced mitochondrial apoptosis by regulating the expression of Bcl-2, Bax, cleaved caspase 3 and cleaved caspase 9. In conclusion, GA alleviates the hepatotoxicity caused by ANIT by regulating bile acids transporters, inflammation and apoptosis, which suggests that GA may be a potential therapeutic agent for cholestasis. [ABSTRACT FROM AUTHOR]

Ferroptosis is a newly identified type of regulated cell death that is affected by lipid peroxidation and reactive oxygen species (ROS). In the current study, we showed that cisplatin and PRLX93936, an analog of erastin that has been tested in clinical trials, demonstrated synergistic effects against non-small cell lung cancer (NSCLC) cells. Cotreatment with cisplatin and PRLX93936 induced ferroptosis, as evidenced by the upregulation of ROS, lipid peroxidation and Fe2+. Further investigation revealed that cotreatment with cisplatin and PRLX93936 inhibited GPX4 and that overexpression of GPX4 prevented cell death. Moreover, the Nrf2/Keap1 pathway also regulated the sensitivity to cisplatin and PRLX93936 in NSCLC cells. Nrf2 silencing increased this sensitivity while inhibition of Keap1 attenuated it. Overall, our data reveal a new effective treatment for NSCLC by synergizing cisplatin and PRLX93936 to induce ferroptosis. • Cisplatin and PRLX93936 synergistically induce cell death of NSCLC cells. •Ferroptosis inhibitors inhibited cell death caused by cisplatin and PRLX93936. •Forced expression of GPX4 attenuated cell death caused by cisplatin and PRLX93936. •Nrf2/Keap1 pathway regulates sensitivity to cisplatin/PRLX93936 in NSCLC cells. [ABSTRACT FROM AUTHOR]

To investigate the role of death-associated protein kinase 1 (DAPK1) in cardiac ischemia reperfusion (I/R) in vivo, and to determine whether the process is regulated by nuclear factor E2-associated factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (keap1). Western blot analysis was used to analyze the expression level of DAPK1 at different time points. The hemodynamic parameters and apoptosis of cardiac I/R injury in vivo were observed using DAPK1 knockdown lentivirus. The oxidative stress of I/R in vivo was observed. Nrf2-IN-1 was applied to determine whether the role of DAPK was regulated by Nrf2/keap1. Results show that the DAPK1 expression increased to a peak after 12 h of I/R. Moreover, the level of DAPK1 expression decreased, as determined by Western blot, after DAPK1 knockdown lentivirus administration. In addition, the hemodynamic parameters of the DAPK1-shRNA group were improved. The apoptosis level (Bax, Bcl-2, cleaved caspase-3, and TUNEL staining) increased in the I/R group, and the DAPK1 knockdown lentivirus could reverse the injury. The oxidative stress indices (CK, cTn-1, CAT, LDH, GSH-PX, MDA, and SOD) also improved in the DAPK1-shRNA group. Finally, Nrf2-IN-1 inhibited tNrf2, nNrf2, and Bcl-2 expression and boosted keap1, Bax, and cleaved caspase-3 expression after DAPK1 lentivirus administration. These findings suggest that DAPK1 may regulate the oxidative stress in cardiac I/R, and Nrf2/keap1 may be the downstream target factor of DAPK1. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the binding affinities of forty-one (41) National Cancer Institute (NCI)- generated compounds, to the Nrf2 ligand, and possible activation of Nrf2 in the MCF-7 cell line. Methods: To investigate the inhibition of the Nrf2/Keap1 complex, the MCF-7 cell line was treated with each of the 41 compounds, at a working concentration of 30 μM. The extent of Nrf2 activation and corresponding Nrf2/Keap1 complex inhibition was evaluated in terms of Nrf2 expression and its antioxidant-associated enzyme gamma-glutamylcysteine synthetase (GCS), using western blot analysis. Results: Twenty-nine compounds out of the 41 targeted compounds activated GCS, and some showed comparable or greater activation capacity than the standard Nrf2 activator tBHQ. To confirm that the activation of GCS was mediated via Nrf2 activation, cell lysates were tested for their Nrf2 protein expression, and it was found that Nrf2 was activated by the examined compounds for more than 24 h, indicating that the effect of the chosen compounds were not transient. Conclusion: These results might be useful for identifying better targets for cytoprotection, and for oxidative stress alleviation through Nrf2 pathway activation. Further studies are required on the effects of these targets on the prevention and treatment of various oxidative stress disorders, including cancer. [ABSTRACT FROM AUTHOR]

Lead, a common metallic contaminant, is widespread in the living environment, and has deleterious effects on the reproductive systems of humans and animals. Although numerous toxic effects of lead have been reported, the effects and underlying mechanisms of the impacts of lead exposure on the female reproductive system, especially oocyte maturation and fertility, remain unknown. In this study, mice were treated by gavage for seven days to evaluate the reproductive damage and role of Nrf2-mediated defense responses during lead exposure. Lead exposure significantly reduced the maturation and fertilization of oocytes in vivo. Additionally, lead exposure triggered oxidative stress with a decreased glutathione level, increased amount of reactive oxygen species, and abnormal mitochondrial distribution. Moreover, lead exposure caused histopathological and ultrastructural changes in oocytes and ovaries, along with decreases in the activities of catalase, glutathione peroxidase, total superoxide dismutase, and glutathione-S transferase, and increases in the levels of malonaldehyde in mouse ovaries. Further experiments demonstrated that lead exposure activated the Nrf2 signaling pathway to protect oocytes against oxidative stress by enhancing the transcription levels of antioxidant enzymes. In conclusion, our study demonstrates that lead activates the Nrf2/Keap1 pathway and impairs oocyte maturation and fertilization by inducing oxidative stress, leading to a decrease in the fertility of female mice.

Abstract Background Age-associated infertility is a problem worldwide, and management of oxidative stress is known to be essential. Nuclear factor-E2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1)-antioxidant response element (ARE) signaling pathway works as an essential defense mechanism against oxidative stress, and an oral drug Dimethylfumarate (DMF) is known to activate the pathway. Methods We tested the hypothesis that oral DMF could alleviate oxidative stress in the ovary, resulting in salvation of age-associated infertility in a mouse model of reproductive age, and we examined the effects of DMF administration. 20 mg/kg DMF was administrated to female mice from 32 to 48 weeks, and Nrf2 levels, antioxidant levels, ovarian reserve, DNA damage, and oxidative stress were examined. Results DMF administration resulted in elevated mRNA and protein levels of Nrf2, antioxidants, and telomere, and serum levels of Nrf2 and anti-mullerian hormone were also elevated. Results of TUNEL assay and Immunohistochemistry of mice ovarian tissues showed that DNA damage and oxidative stress were decreased by DMF administration, and significantly more oocytes were collected along with preservation of 60% more primordial follicles. Conclusions Our data suggest that DMF administration activates the Nrf2/Keap1 pathway, elevate levels of antioxidants, and decrease DNA damage and oxidative stress, resulting in improved ovarian reserve in the mouse ovary.

Key points: Nrf2 is a master regulator of endogenous cellular defences, governing the expression of more than 200 cytoprotective proteins, including a panel of antioxidant enzymes.Nrf2 plays an important role in redox haemostasis of skeletal muscle in response to the increased generation of reactive oxygen species during contraction.Employing skeletal muscle‐specific transgenic mouse models with unbiased‐omic approaches, we uncovered new target proteins, downstream pathways and molecular networks of Nrf2 in skeletal muscle following Nrf2 or Keap1 deletion.Based on the findings, we proposed a two‐way model to understand Nrf2 function: a tonic effect through a Keap1‐independent mechanism under basal conditions and an induced effect through a Keap1‐dependent mechanism in response to oxidative and other stresses. Although Nrf2 has been recognized as a master regulator of cytoprotection, its functional significance remains to be completely defined. We hypothesized that proteomic/bioinformatic analyses from Nrf2‐deficient or overexpressed skeletal muscle tissues will provide a broader spectrum of Nrf2 targets and downstream pathways than are currently known. To this end, we created two transgenic mouse models; the iMS‐Nrf2flox/flox and iMS‐Keap1flox/flox, employing which we demonstrated that selective deletion of skeletal muscle Nrf2 or Keap1 separately impaired or improved skeletal muscle function. Mass spectrometry revealed that Nrf2‐KO changed expression of 114 proteins while Keap1‐KO changed expression of 117 proteins with 10 proteins in common between the groups. Gene ontology analysis suggested that Nrf2 KO‐changed proteins are involved in metabolism of oxidoreduction coenzymes, purine ribonucleoside triphosphate, ATP and propanoate, which are considered as the basal function of Nrf2, while Keap1 KO‐changed proteins are involved in cellular detoxification, NADP metabolism, glutathione metabolism and the electron transport chain, which belong to the induced effect of Nrf2. Canonical pathway analysis suggested that Keap1‐KO activated four pathways, whereas Nrf2‐KO did not. Ingenuity pathway analysis further revealed that Nrf2‐KO and Keap1‐KO impacted different signal proteins and functions. Finally, we validated the proteomic and bioinformatics data by analysing glutathione metabolism and mitochondrial function. In conclusion, we found that Nrf2‐targeted proteins are assigned to two groups: one mediates the tonic effects evoked by a low level of Nrf2 at basal condition; the other is responsible for the inducible effects evoked by a surge of Nrf2 that is dependent on a Keap1 mechanism. Key points: Nrf2 is a master regulator of endogenous cellular defences, governing the expression of more than 200 cytoprotective proteins, including a panel of antioxidant enzymes.Nrf2 plays an important role in redox haemostasis of skeletal muscle in response to the increased generation of reactive oxygen species during contraction.Employing skeletal muscle‐specific transgenic mouse models with unbiased‐omic approaches, we uncovered new target proteins, downstream pathways and molecular networks of Nrf2 in skeletal muscle following Nrf2 or Keap1 deletion.Based on the findings, we proposed a two‐way model to understand Nrf2 function: a tonic effect through a Keap1‐independent mechanism under basal conditions and an induced effect through a Keap1‐dependent mechanism in response to oxidative and other stresses. [ABSTRACT FROM AUTHOR]

白内障是由于晶状体蛋白发生变性导致晶状体混浊,其主要症状是视力障碍,随着世界人均寿命的延长,白内障 患者不断增多,目前对白内障的治疗主要以手术方式为主,晶状体再生及预防白内障方面正在不断探索。该文围绕当前比较流行 的手术治疗方式,以及再生晶状体研究中内源性干细胞原位再生晶状体治疗婴幼儿白内障方面,晶状体内谷胱甘肽的稳态在阻 止或延缓老年性白内障发生方面,核因子E2相关因子/多区域阻遏蛋白抗氧化体系及姜黄素药物预防白内障等方面进行综述。 [ABSTRACT FROM AUTHOR]

Oxidative stress is frequently generated in cells of organisms exposed to environmental pollutants. The production of reactive oxygen species can have either adaptive or maladaptive consequences for the organism as well as for the entire population. However, regarding fish species and other invertebrates exposed to aquatic xenobiotics, the signaling pathways of oxidative stress still lacks a comprehensive characterization. After reviewing the recent literature, we show that important pathways described in mammals are also activated in aquatic species in response to a variety of xenobiotics. A central actor is the Nrf2/Keap1 pathway, which regulates the expression of ARE‐driven genes including Gr, Gpx, or Cat. Other important activated pathways concern PPAR, MAPKs, NF‐κB, and even AhR. Moreover, the autophagy and apoptosis pathways are also involved in the cellular response to oxidative stress. Importantly, there exists crosstalks between these pathways, which together activate a complex cellular antioxidative machinery in response to different xenobiotics. However, our knowledge of these responses in aquatic organisms is still fragmentary. Efforts should be made to extend the number of studied species and better characterize the organ‐dependency and age‐dependency of the responses. However, the huge number and variety of chemicals present in the environment makes the task difficult. Deciphering these key pathways can help to understand the mode of action of pollutants and consequently help to assess the environmental risk in aquatic ecosystems. Research Highlights: Pollutants inducing oxidative stress in aquatic organisms activate a stress responseSignaling pathways concern Nrf2/Keap1, AhR, PPAR, NF‐κB, MAPKs, autophagy, apoptosis, and their crosstalkThese pathways can be used for environmental risk assessment [ABSTRACT FROM AUTHOR]

Aspirin (ASA) is a widely used non-steroidal anti-inflammatory drug. Its high detection frequency in various waterborne and environmental residues has drawn wide attention. Limited information were provided for the effects of aspirin exposure on oxidative stress signaling pathway in fish, which is closely related to pathological and immunological process of fish. In this study, a small fish - Mugilogobius abei (M. abei) distributing widely in aquatic ecosystems in southern China, was employed as testing organism and the key genes of the detoxification metabolism were cloned for the first time. The responses of Nrf2/Keap1 signaling pathway were investigated under the environmentally relevant concentration aspirin exposure (0.5 μg L−1, 5 μg L−1, and 50 μg L−1) for 24 h, 72 h, and 168 h then. The transcriptional expression of the key genes (Nrf2, Keap1, GCLC, GPx, GST, SOD, CAT, Trx2, and TrxR) as well as the changes of the related enzymatic activities (GPx, GST, SOD, and CAT) and GSH and MDA content were also determined. Results showed that Nrf2 and Keap1 gene expression displayed a negative correlation to some extent under ASA exposure, the transcriptional expressions of the downstream related genes (GCLC, GST, SOD, CAT, Trx2, and TrxR) in Nrf2/Keap1 signaling pathway showed inhibition at 24 h but induction at 72 h and 168 h. At the protein level, ASA exposure can improve the antioxidant capacity by increasing GSH synthesis and enzymatic activity of GPx, GST, SOD, and CAT to reduce the degree of lipid peroxidation. We proposed that ASA exposure may interfere with the redox balance in M. abei at an early stage but sub-chronic ASA exposure can activate the Nrf2 signaling pathway to improve the antioxidant capacity of M. abei. [ABSTRACT FROM AUTHOR]

• IRB ameliorates high glucose-induced cell injury in RAW264.7 macrophages. • IRB activates the Nrf2 pathway and decrease the release of ROS. • IRB suppresses the expression of the NLRP3 inflammasome. • IRB alleviated the inflammatory reaction in DN mice. • IRB alleviates the NLRP3 inflammatory response by regulating the Nrf2 signalling pathway in the kidneys of DN mice. Diabetic nephropathy (DN) is characterized by albuminuria and renal dysfunction caused by diabetes. At present there is no specific treatment for DN. Irbesartan (IRB) is an angiotensin receptor inhibitor indicated for the treatment of hypertension and DN. However, the underlying molecular mechanisms of IRB on DN remains obscure. RAW264.7 macrophages were incubated in RPMI-1640, cell viability was evaluated by CCK-8 assays, transcriptional level of proinflammatory cytokines and was measured by ELISA and qPCR, NLRP3 inflammasome and Nrf2/Keap1 related proteins were measured by Western blotting and immunohistochemistry. Streptozotocin (STZ)-induced diabetic male C57BL/6 mice were used to evaluate the therapeutic effect of IRB on DN. Key findings First, we found that IRB improved high glucose-induced cell inflammation by inhibiting the transcription of IL-1β and IL-18. IRB activated the Nrf2/Keap1 pathway and decreased the release of reactive oxygen species (ROS). IRB also suppressed the expression of NLRP3 and caspase-1. IRB combined with the N-acetylcysteine (NAC) significantly inhibited the activation of NLRP3 inflammasomes. Conversely, IRB combined with the Nrf2-related inhibitor ML385 enhanced NLRP3 inflammasome activation, suggesting that IRB suppressed NLRP3 inflammasome via the Nrf2 pathway. In vivo study, HE staining and immunohistochemistry analysis further showed that IRB ameliorated high glucose-induced renal injury by elevating the expression of the Nrf2/Keap1 signaling pathway and suppressing the proinflammatory cytokine and NLRP3 inflammasome activation. Our results suggested that IRB ameliorates diabetic nephropathy by activating the Nrf2/Keap1 pathway and suppressing the NLRP3 inflammasomes in vivo and in vitro. These findings provide new therapeutic strategies of diabetic nephropathy. [ABSTRACT FROM AUTHOR]

As a canonical iron-dependent form of regulated cell death (RCD), ferroptosis plays a crucial role in chemical-induced liver injuries. Previous studies have demonstrated that xanthohumol (Xh), a natural prenylflavonoid isolated from hops, exhibits anti-inflammatory, anti-antioxidative and hepatoprotective properties. However, the regulatory effects of Xh on hepatic ferroptosis and the underlying mechanism have not yet been fully elucidated. To investigate the hepatoprotective effects of Xh against drug-induced liver injury (DILI) and the regulatory effects of Xh on hepatic ferroptosis, as well as to reveal the underlying molecular mechanisms. The hepatoprotective benefits of Xh were investigated in APAP-induced liver injury (AILI) mice and HepaRG cells. Xh was administered intraperitoneally to assess its in vivo effects. Histological and biochemical studies were carried out to evaluate liver damage. A series of ferroptosis-related markers, including intracellular Fe2+ levels, ROS and GSH levels, the levels of MDA, LPO and 4-HNE, as well as the expression levels of ferroptosis-related proteins and modulators were quantified both in vivo and in vitro. The modified peptides of Keap1 by Xh were characterized utilizing nano LC-MS/MS. Xh remarkably suppresses hepatic ferroptosis and ameliorates AILI both in vitro and in viv o, via suppressing Fe2+ accumulation, ROS formation, MDA generation and GSH depletion, these observations could be considerably mitigated by the ferroptosis inhibitor ferrostatin-1 (Fer-1). Mechanistically, Xh could significantly activate the Nrf2/xCT/GPX4 signaling pathway to counteract AILI-induced hepatocyte ferroptosis. Further investigations showed that Xh could covalently modify three functional cysteine residues (cys151, 273, 288) of Keap1, which in turn, reduced the ubiquitination rates of Nrf2 and prolonged its degradation half-life. Xh evidently suppresses hepatic ferroptosis and ameliorates AILI via covalent modifying three key cysteines of Keap1 and activating Nrf2/xCT/GPX4 signaling pathway. [ABSTRACT FROM AUTHOR]

Avermectins, as a new type of environmental pollutant, have received significant attention in recent years. Previous research has shown that acute exposure to avermectins can induce oxidative stress and inflammation in non-target fish species, such as carp. Flavonoid lignans, particularly Silybin, have demonstrated promising biological activities, including regulation of non-alcoholic fatty liver and cerebral ischemia-reperfusion injury. This study aims to investigate the impact of dietary supplementation with Silybin on the intestinal damage in carp caused by chronic exposure to avermectins and to improve the health status and production of carp in aquaculture. Silybin was used as a dietary supplement by adding it to the experimental feed, and an animal experimental model was utilized to assess its effects on oxidative stress, inflammation, and cell apoptosis in carp intestine. Additionally, intestinal barrier integrity, digestive capacity, and fish growth were evaluated. The results indicated that dietary supplementation with Silybin effectively alleviated the oxidative stress induced by chronic exposure to avermectins in carp intestine. Furthermore, Silybin improved intestinal barrier integrity and digestive capacity by modulating the Nrf2/Keap1 pathway. This study demonstrates that dietary supplementation with Silybin can effectively mitigate the intestinal damage caused by chronic exposure to avermectins in carp, providing a sustainable solution for the aquaculture industry to enhance the overall health and production of cultured fish. The research expands our understanding of avermectin environmental pollution and offers a potential remediation approach. [Display omitted] • Silybin protects the intestinal tract of carp from chronic exposure to Avermectin. • Silybin exerts antioxidant effects in the oxidative stress of carp intestinal tract induced by chronic Avermectin exposure. • Silybin alleviates intestinal inflammation induced by chronic Avermectin exposure. • Silybin exerts anti-apoptotic effects in carp intestinal tissue exposed to chronic Avermectin. • Silybin reverses the intestinal developmental and growth inhibition in carp fry caused by chronic Avermectin exposure. [ABSTRACT FROM AUTHOR]

Abstract Background Fluoride (Fl) exposure engenders neurodegeneration and induces oxidative stress in the brain. Therefore, the mechanism of Fl-induced neurotoxic effects needs to be determined. The aim of this study was to investigate the neuroprotective effects of EGCG (40 mg/kg) on Fl (25 mg/kg/bw)-induced oxidative stress mediated neurotoxicity with special emphasis on the hippocampus (4 weeks). Results Fl-intoxicated rat shows an increased Fl concentration along with the decreased neurotransmitter (AChE, NP, DA and 5-HT) activity in the brain. The oxidative stress markers (ROS, TBARS, NO, and PC) was significantly increased with decreased enzymatic (SOD, CAT, GPx, GR, GST, and G6PD) and nonenzymatic antioxidants (GSH, TSH, and Vit.C) in the rat hippocampus. Moreover, results showed that increases in intrinsic and extrinsic apoptotic pathway leading to DNA damage and cell death were also proved by the immunohistochemical, histological, and ultra-structural studies in the Fl-treated rat hippocampus. In this context, pre-administration of EGCG significantly improved the oxidative stress, biochemical changes, cellular apoptotic and histological alternations by Fl in the hippocampus of rats. Conclusions These results confirmed the EGCG supplementation might attenuate the Fl-induced neurotoxicity via Nrf2/Keap1 signaling pathway in the rat hippocampus.

Lung adenocarcinomas exhibit chemoresistance mostly due to deregulation of nuclear factor erythroid-derived 2-like 2 (Nrf2). Epigallocatechin gallate (EGCG), was investigated for altering Nrf2 mediated etoposide resistance in different lung adenocarcinoma cells. In A549, EGCG downregulated nuclear Nrf2 by upregulating the nuclear localization of Keap1 whereas in NCIH23, EGCG augmented Nrf2 by reducing Keap1. In Keap-1 independent mode EGCG increased p53, and decreased p21, in A549 but in NCIH23 vice versa was observed. EGCG enhanced retinoid X receptor (RXR) in both A549 and NCIH23 but retinoid acid receptor (RAR) was aggravated in A549 and suppressed in NCIH23. Though the direction of Nrf2 regulation was opposite in two cell lines, optimum level of Nrf2 was maintained which increased responsiveness towards etoposide. EGCG sensitized/potentiated lung adenocarcinoma cells towards chemotherapy by inducing G2/M arrest and suppressing the multi-drug resistance. Thus, EGCG might have a novel implication in chemotherapeutic management of lung cancer cells.

p62 is a highly conserved, multi-domain, and multi-functional adaptor protein critically involved in several important cellular processes. Via its pronounced domain architecture, p62 binds to numerous interaction partners, thereby influencing key pathways that regulate tissue homeostasis, inflammation, and several common diseases including cancer. Via binding of ubiquitin chains, p62 acts in an anti-inflammatory manner as an adaptor for the auto-, xeno-, and mitophagy-dependent degradation of proteins, pathogens, and mitochondria. Furthermore, p62 is a negative regulator of inflammasome complexes. The transcription factor Nrf2 regulates expression of a bundle of ROS detoxifying genes. p62 activates Nrf2 by interaction with and autophagosomal degradation of the Nrf2 inhibitor Keap1. Moreover, p62 activates mTOR, the central kinase of the mTORC1 sensor complex that controls cell proliferation and differentiation. Through different mechanisms, p62 acts as a positive regulator of the transcription factor NF-κB, a central player in inflammation and cancer development. Therefore, p62 represents not only a cargo receptor for autophagy, but also a central signaling hub, linking several important pro- and anti-inflammatory pathways. This review aims to summarize knowledge about the molecular mechanisms underlying the roles of p62 in health and disease. In particular, different types of tumors are characterized by deregulated levels of p62. The elucidation of how p62 contributes to inflammation and cancer progression at the molecular level might promote the development of novel therapeutic strategies.

Nrf2/Keap1 pathway is associated with oxidative stress. l -carnitine is currently under preclinical evaluation as a antioxidant, but the use of l -carnitine in aquaculture has been poorly evaluated and so far no mechanism has been demonstrated. Here, we explored the effects of l -carnitine in vitro and in vivo and discussed the possible molecular mechanisms involved. Firstly, Nrf2 -siRNA significantly knocked down the mRNA level of Nrf2 in FHM cells. Thus, the activities of antioxidant enzymes (T-SOD, CAT, GSH-PX) and the level of antioxidant substance (GSH) and the level of MDA showed that Nrf2 -siRNA pretreatment weakened the protective effect of l -carnitine. Moreover, the mRNA levels of Keap1 , Nrf2 , Maf and HO-1 indicated that l -carnitine regulated Nrf2/Keap1 activation. Furthermore, oxidized fish oil remarkably suppressed growth in Rhynchocypris lagowski Dybowski, and the lower antioxidant capacity was also observed in liver. According to the results of immune related indexes (the levels of IL-1β, TNF-α, LZM, AKP) in serum and the mRNA levels of immune related genes (NF-κB , IL-1β , TNF-α , IL-8 , IL-10 and TGF-β) in liver, oxidized fish oil also induced inflammatory response in fish. Also, l -carnitine supplementation can relieve this bad condition. In conclusion, l -carnitine regulated Nrf2/Keap1 activation in vitro and in vivo and protected oxidized fish oil-induced inflammation response by inhibiting the NF-κB signaling pathway in Rhynchocypris lagowski Dybowski. • Nrf2-siRNA weakened the protective effect of l -carnitine in FHM cells. • Oxidized fish oil suppressed growth performance, antioxidant capacity and immunity. • The protective effect of l -carnitine was due to the activation of Nrf2/Keap1 and NF-κB signaling. [ABSTRACT FROM AUTHOR]

Abstract Mitochondrial dysfunctions induced by oxidative stress could play a pivotal role in the development of testicular damage and degeneration, leading to impaired fertility in adulthood. MitoQ as mitochondria-targeted antioxidant has been used in many diseases for a long time, but its therapeutic effects on testicular injury 'have not been reported yet. Here, we examined the protective action mechanism of MitoQ on testicular injury from oxidative stress induced by triptolide (TP). Mice were orally administrated with MitoQ (1.3, 2.6 and 5.2mg/kg, respectively) in a TP-induced model of testicular damage for 14 days. And then testis injuries were comprehensively evaluated in terms of morphological changes, spermatogenesis assessment, blood-testis barrier (BTB) integrity, and apoptosis. The results demonstrated MitoQ effectively increased testicular weight, maintained the integrity of BTB, protected microstructure of testicular tissue and sperm morphology by inhibition of oxidative stress. Further mechanism studies revealed that MitoQ markedly activates the Keap1-Nrf2 antioxidative defense system characterized by increasing the expression of Nrf2 and its target genes HO-1 and NQO1. Meanwhile, MitoQ upregulated the expression of mitochondrial dynamics proteins Mfn2 and Drp-1and exerted a protective effect on mitochondria. On this basis, the results from pharmacokinetic study indicated that the MitoQ could enter into testis tissues after oral administration in despite of the low absolute bioavailability, which provided the material basis for MitoQ in the treatment of testicular damage. More importantly, MitoQ reached mitochondria quickly and had an outstanding feature of mitochondria targeting in Sertoli cells. Therefore, these results provide information for the application of MitoQ against testicular injury diseases. Graphical abstract Unlabelled Image Highlights • MitoQ inhibits oxidative stress to attenuate the testis injury. • MitoQ upregulates mitochondrial dynamics protein Mfn2 and Drp-1. • MitoQ activates Nrf2/Keap1 signaling to ameliorate the oxidative stress. • MitoQ could be exposed to testis tissue by pharmacokinetic study. • MitoQ is quickly accumulated in mitochondria of sertoli cells. [ABSTRACT FROM AUTHOR]