Nrf2 Research Articles

Targeting Immunoproteasome in Polarized Macrophages Ameliorates Experimental Emphysema Via Activating NRF1/2-P62 Axis and Suppressing IRF4 Transcription.

Chronic obstructive pulmonary disease (COPD) stands as the prevailing chronic airway ailment, characterized by chronic bronchitis and emphysema. Current medications fall short in treatment of these diseases, underscoring the urgent need for effective therapy. Prior research indicated immunoproteasome inhibition alleviated various inflammatory diseases by modulating immune cell functions. However, its therapeutic potential in COPD remains largely unexplored. Here, an elevated expression of immunoproteasome subunits LMP2 and LMP7 in the macrophages isolated from mouse with LPS/Elastase-induced emphysema and polarized macrophages in vitro is observed. Subsequently, intranasal administration of the immunoproteasome-specific inhibitor ONX-0914 significantly mitigated COPD-associated airway inflammation and improved lung function in mice by suppressing macrophage polarization. Additionally, ONX-0914 capsulated in PLGA nanoparticles exhibited more pronounced therapeutic effect on COPD than naked ONX-0914 by targeting immunoproteasome in polarized macrophages. Mechanistically, ONX-0914 activated autophagy and endoplasmic reticulum (ER) stress are not attribute to the ONX-0914 mediated suppression of macrophage polarization. Intriguingly, ONX-0914 inhibited M1 polarization through the nuclear factor erythroid 2-related factor-1 (NRF1) and NRF2-P62 axis, while the suppression of M2 polarization is regulated by inhibiting the transcription of interferon regulatory factor 4 (IRF4). In summary, the findings suggest that targeting immunoproteasome in macrophages holds promise as a therapeutic strategy for COPD.

Potential benefits of advanced chelate-based trace minerals in improving bone mineralization, antioxidant status, immunity, and gene expression modulation in heat-stressed broilers.

Organic sources of trace minerals (TM) in broiler diets are more bioavailable and stable than inorganic sources, making them particularly beneficial during challenging periods such as heat stress (HS) conditions. A 42-d study investigated the effects of using advanced chelate technology-based TM (ACTM) or adding varying amounts of ACTM to broiler diets during HS conditions. The study involved 672 male broiler chickens in 7 treatment groups, including a thermoneutral control (TNC) group and six HS treatments. There were 8 replicate pens per treatment and 12 birds per replicate. The six HS treatments included birds exposed to a cyclic HS environment (34°C) for 8 h and were as follows: HSC, which consisted of the same basal diet with the recommended ITM levels; ACTM50 and ACTM100, which replaced the basal diet with 50% and 100% ACTM instead of ITM; ITM+ACTM12.5 and ITM+ACTM25, which involved adding extra ACTM to the ITM basal diet at 12.5% and 25%, respectively; and ITM125, which used 125% of the recommended levels of ITM in the basal diet. Compared with the HSC treatment, the TNC, ACTM100, and ITM+ACTM25 treatments resulted in increased (P < 0.05) body weight; tibia weight; tibia ash, phosphorus, iron, and manganese contents; secondary antibody titers; and serum TAC and SOD values but decreased (P < 0.05) serum MDA concentrations and the expression levels of the hepatic genes IL-1β, IL-6, and INF-γ. The TNC and ACTM100 groups also showed greater (P < 0.05) feed efficiency, tibia length, tibia zinc content, and hepatic SOD1 expression but exhibited reduced (P < 0.05) hepatic NF-kB expression. Significant increases (P < 0.05) in primary anti-NDV titers, serum GPx1 activity, and Nrf2 and GPx1 gene expression levels were also detected in the ACTM100, ITM+ACTM12.5, and ITM+ACTM25 groups. In conclusion, the findings suggest that replacing ITM with ACTM or adding ACTM to ITM diets, especially at a 25% higher dose, can effectively protect broilers from heat stress by promoting growth, reducing inflammation, and increasing the expression of antioxidant proteins.

The Growth Inhibitory Effect of Resveratrol and Gallic Acid on Prostate Cancer Cell Lines through the Alteration of Oxidative Stress Balance: The Interplay between Nrf2, HO-1, and BACH1 Genes.

The association between oxidative stress and prostate cancer (PC) has been demonstrated both epidemiologically and experimentally. Balance in reactive oxygen species (ROS) levels depends on multiple factors, such as the expression of Nrf2, HO-1, and BACH1 genes. Natural polyphenols, such as resveratrol (RSV) and gallic acid (GA), affect cellular oxidative profiles. The present study investigated the possible effects of GA and RSV on the oxidative profiles of PC3 and DU145 cells, as well as Nrf2, HO-1, and BACH1 gene expression to achieve an understanding of the mechanisms involved. PC3 and DU145 cells were treated with ascending concentrations of RSV and GA for 72 h. Then cell growth and mRNA expression of Nrf2, HO-1, and BACH1 genes were analyzed by real-time PCR. Various spectrophotometric analyses were performed to measure oxidative stress markers. RSV and GA significantly decreased the growth of PC3 and DU145 cells compared to the control group in a concentration-dependent manner. RSV and GA also decreased ROS production in PC3 cells, but in DU145 cells, only the latter polyphenol significantly decreased ROS content. In addition, RSV and GA had ameliorating effects on SOD, GR, GPX, and CAT activities and GSH levels in both cell lines. Also, RSV and GA induced HO- 1 and Nrf2 gene expression in both cell lines. BACH1 gene expression was induced by RSV only at lower concentrations, in contrast to GA in both cell lines. Our data suggest that RSV and GA can prevent the growth of prostate cancer cells by disrupting oxidative stress-related pathways, such as changes in Nrf2, HO-1, and BACH1 gene expression.

Amelioration of full-thickness cutaneous wound healing using stem cell exosome and zinc oxide nanoparticles in rats

BackgroundWound healing is a complex procedure that requires the coordination of several factors, so this study aimed to assess the zinc oxide nanoparticles’ regenerated effect and stem cell exosomes on full-thickness wounds in rats. MethodsSeventy-two Wistar male rats were subjected to a full-thickness skin defect (20 mm2) on the dorsal surface of each rat between two shoulder joints. The rats were randomized into four groups (18/group) according to wound treatments. The wounds were irrigated with normal saline (Control group), or the wound's edges were subcutaneously injected daily with 0.3 ml of exosome (Exo-group), or 1 ml of zinc oxide nanoparticles (ZnO2-NPs group), or 0.3 ml of exosome in combined with 1 ml of zinc oxide nanoparticles (Exo/ZnO2-NPs group). On the 7th, 14th, and 21st days post-wounding, the weight of the rats, the wound healing breaking strength, the wound size, and the contraction percent were evaluated. Six rats in each group were euthanized at each time point for histopathological, immunohistochemical examination of collagen, the levels of alpha-smooth muscle actin (α-SMA), and epidermal growth factor receptor (EGFR). additionally, the gene expression analysis of the relative renal nuclear factor erythroid 2-related factor2 (Nrf2 mRNA), Transforming growth factor beta-1 (TGFβ1), fibroblast growth factor-7 (FGF7), Transforming growth factor beta-1 (TGFβ1), Lysyl oxidase (LOX), and Vascular endothelial growth factor (VEGF) were applied. ResultsThe Exo-group exhibited a significant decrease in wound size and a significant increase in wound contraction compared with other groups. Histopathologically evaluation during the three intervals revealed that the Exo-group had the highest collagen deposition area with a significant reduction of the granulation tissue. Moreover, upregulated gene expression profiles of the growth factors genes at all time points post-wounding. DiscussionThe exosomes-treated group revealed superior wound healing and contraction, with minimal inflammatory signs, higher angiogenesis, and myofibroblasts, and associated with higher growth factor expression genes compared to the other groups. ConclusionsExosome-based therapy demonstrates potential as a treatment method to promote and accelerate wound healing by modulating angiogenesis, re-epithelialization, collagen deposition, and gene expression profiles.

Neuropilin-2 expressing cells in breast cancer are S-nitrosylation hubs that mitigate radiation-induced oxidative stress.

The high rate of recurrence after radiation therapy in triple-negative breast cancer (TNBC) indicates that novel approaches and targets are needed to enhance radiosensitivity. Here, we report that neuropilin-2 (NRP2), a receptor for vascular endothelial growth factor (VEGF) that is enriched on sub-populations of TNBC cells with stem cell properties, is an effective therapeutic target for sensitizing TNBC to radiotherapy. Specifically, VEGF/NRP2 signaling induces nitric oxide synthase 2 (NOS2) transcription by a mechanism dependent on Gli1. NRP2-expressing tumor cells serve as a hub to produce nitric oxide (NO), an autocrine and paracrine signaling metabolite, which promotes cysteine-nitrosylation of Kelch-like ECH-asssociated protein 1 (KEAP1) and, consequently, nuclear factor erythroid 2-related factor 2 (NFE2L2)-mediated transcription of antioxidant response genes. Inhibiting VEGF binding to NRP2, using a humanized monoclonal antibody (mAb), results in NFE2L2 degradation via KEAP1 rendering cell lines and organoids vulnerable to irradiation. Importantly, treatment of patient-derived xenografts with the NRP2 mAb and radiation resulted in significant tumor necrosis and regression compared to radiation alone. Together, these findings reveal a targetable mechanism of radioresistance and they support the use of NRP2 mAb as an effective radiosensitizer in TNBC.

Nrf2 Activation in Keratinocytes: A Central Role in Diabetes-Associated Wound Healing.

Wound healing is a complex biological process crucial for tissue repair, wherein keratinocytes play a pivotal role in initiating, sustaining and completing the cascade. Various local and systemic factors, such as lifestyle, age metabolic disorders and vascular insufficiency, can influence this process, and in the context of diabetic wounds, disrupted biological mechanisms, including inflammation, tissue hypoxia, decrease in collagen production along with increased oxidative stress and keratinocyte dysfunction, contribute to delayed healing. During re-epithelialisation, keratinocytes undergo rapid multiplication and migration, forming a dense hyperproliferative epithelial layer that restores the epidermal barrier. Nuclear factor-erythroid 2-related factor (Nrf2), a vital transcription factor, emerges as a central regulator in managing antioxidant proteins and detoxifying enzymes, serving as a guardian against elevated reactive oxygen species (ROS) levels during stress. Nrf2 also orchestrates angiogenesis and anti-inflammatory responses crucial for wound repair. Studies demonstrate that under high-glucose conditions, Nrf2 activation promotes wound healing by enhancing cell proliferation and migration while reducing apoptosis. Nrf2 activators stimulate endogenous antioxidant production, thereby mitigating oxidative stress. Furthermore, Nrf2 upregulation is associated with decreased expression of cytokines such as TNF-α and IL- 6. Recent research underscores the potential of bioactive molecules, including dietary polyphenols, traditional medicinal compounds and pharmacological agents, in activating Nrf2 and preventing diseases such as diabetes due to their robust antioxidative properties. This review aims to investigate the activation of Nrf2 by these bioactive molecules in cultured keratinocytes and animal models, elucidating the key molecular regulatory mechanisms involved in alleviating oxidative stress and facilitating the diabetic wound healing process. Understanding these complex pathways may offer insights into novel therapeutic strategies for enhanced wound healing in diabetes-associated complications.

Therapeutic Potential of Capsaicin in Various Neurodegenerative Diseases with Special Focus on Nrf2 Signaling.

Neurodegenerative disease is mainly characterized by the accumulation of misfolded proteins, contributing to mitochondrial impairments, increased production of proinflammatory cytokines and reactive oxygen species, and neuroinflammation resulting in synaptic loss and neuronal loss. These pathophysiological factors are a serious concern in the treatment of neurodegenerative diseases. Based on the symptoms of various neurodegenerative diseases, different treatments are available, but they have serious side effects and fail in clinical trials, too. Therefore, treatments for neurodegenerative diseases are still a challenge at present. Thus, it is important to study an alternative option. Capsaicin is a naturally occurring alkaloid found in capsicum. Besides the TRPV1 receptor activator in nociception, capsaicin showed a protective effect in brain-related disorders. Capsaicin also reduces the aggregation of misfolded proteins, improves mitochondrial function, and decreases ROS generation. Its antioxidant role is due to increased expression of an nrf2-mediated signaling pathway. Nrf2 is a nuclear erythroid 2-related factor, a transcription factor, which has a crucial role in maintaining the normal function of mitochondria and the cellular defense system against oxidative stress. Intriguingly, Nrf2 mediated pathway improved the upregulation of antioxidant genes and inhibition of microglial-induced inflammation, improved mitochondrial resilience and functions, leading to decreased ROS in neurodegenerative conditions, suggesting that Nrf2 activation could be a better therapeutic approach to target pathophysiology of neurodegenerative disease. Therefore, the present review has evaluated the potential role of capsaicin as a pharmacological agent for the treatment and management of various neurodegenerative diseases via the Nrf2-mediated signaling pathway.

Analysis of Expression of the GRIPAP1, DLG4, KIF1B, NGFRAP1, and NRF1 Genes in Peripheral Blood of the Patients with Parkinson’s Disease in the Early Clinical Stages

Analysis of Expression of the GRIPAP1, DLG4, KIF1B, NGFRAP1, and NRF1 Genes in Peripheral Blood of the Patients with Parkinson’s Disease in the Early Clinical Stages

Tile: Construction of a specific nanoprobe for scavenging ROS in hypobaric hypoxia induced brain injury of mice

The prevention and treatment of hypobaric hypoxia brain injury (HHBI) remains an unprecedented challenge due to the complex oxidative stress response at the damage site. In this study, RuCO phthalocyanine compound (RuPc) and bovine serum albumin (BSA) were self-assembled to obtain RuPc-BSA nanoparticles for HHBI therapy. As a nanoprobe carrying and storing carbon monoxide (CO), RuPc-BSA delivers CO to pathologically damaged areas of the brain. CO specifically attaches itself to the heme functional groups on mitochondria and restricts the source of reactive oxygen species (ROS) generation. RuPc-BSA nanoparticles have been demonstrated in vitro to exhibit amazing stability as well as remarkable scavenging activity on hydroxyl radical, superoxide anion, and hydrogen peroxide. In vivo experiments showed that ROS levels in the brain of HHBI rats pretreated with RuPc-BSA decreased significantly, and neuronal function and oxidative stress levels were alleviated. Western blot and qRT-RCR results indicated that RuPc-BSA restricted the protein levels of Keap1, whereas enhanced the gene and protein levels of Nrf2. This study demonstrated that RuPc-BSA can ameliorate HHBI of mice by scavenging ROS partly via activating Keap1/Nrf2 signaling pathway.

Mechanistic studies on the alleviation of lipid accumulation and oxidative stress by Majia pomelo seed oil

In this study, hot-pressed Majia pomelo seed oil (MPSO), which has high oxidative stability and antioxidant capacity, was used to study the effects and potential mechanisms of lipid accumulation and oxidative stress. The results indicated that the low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and triglycerides (TG) levels in HepG2 cells were lowest when the MPSO concentration was 0.5 mg/mL. At this concentration, MPSO could alleviate oleic acid (OA)-induced lipid accumulation, reduce intracellular lipid level, and decrease lipid and cholesterol synthesis by increasing AMPK phosphorylation and down-regulating the expression levels of genes and proteins of ACC, SREBP-1c, PPAR-γ, and FAS. Meanwhile, MPSO can reduce reactive oxygen species (ROS) and malondialdehyde (MDA) content and enhance superoxide dismutase (SOD) content in HepG2 cells by down-regulating the expression levels of Nrf2, γ-GCS, and HO-1 genes and proteins, thus acting as an anti-oxidative stress. In addition, molecular docking results indicated that the active ingredients of MPSO could effectively bind AMPK protein and Keap1 protein, which further demonstrated that MPSO could alleviate lipid accumulation and oxidative stress.

Evaluation of Antioxidant Effects of Coenzyme Q10 against Hyperglycemia-Mediated Oxidative Stress by Focusing on Nrf2/Keap1/HO-1 Signaling Pathway in the Liver of Diabetic Rats.

Hyperglycemia-induced oxidative stress can damage the liver and lead to diabetes complications. Coenzyme Q10 (CoQ-10) reduces diabetes-related oxidative stress. However, its molecular mechanisms are still unclear. This study aimed to examine CoQ-10's antioxidant capabilities against hyperglycemia-induced oxidative stress in the livers of diabetic rats, specifically targeting the Nrf2/Keap1/ARE signaling pathway. This study was conducted between 2020-2021 at Arak University of Medical Sciences. A total of 30 male adult Wistar rats (8 weeks old) weighing 220-250 g were randomly assigned to five groups (n=6 in each group): control healthy, sesame oil (CoQ-10 solvent), CoQ-10 (10 mg/Kg), diabetic, and diabetic+CoQ-10. Liver oxidative stress indicators, including malondialdehyde, catalase, glutathione peroxidase, and glutathione, were estimated using the spectrophotometry method. Nrf2, Keap1, HO-1, and NQO1 gene expressions were measured using real-time PCR tests in the liver tissue. All treatments were conducted for 6 weeks. Statistical analysis was performed using SPSS software. One-way ANOVA followed by LSD's or Tukey's post hoc tests were used to compare the results of different groups. P<0.05 was considered statistically significant. The findings showed that induction of diabetes significantly increased Keap1 expression (2.1±0.9 folds, P=0.01), and significantly inhibited the mRNA expression of Nrf2 (0.38±0.2 folds, P=0.009), HO-1 (0.27±0.1 folds, P=0.02), and NQO1 (0.26±0.1 folds P=0.01), compared with the healthy group. In the diabetic group, the activity of glutathione peroxidase, catalase enzymes, and glutathione levels was decreased with an increase in malondialdehyde level. CoQ-10 supplementation significantly up-regulated the expressions of Nrf2 (0.85±0.3, P=0.04), HO-1 (0.94±0.2, P=0.04), NQO1 (0.88±0.5, P=0.03) genes, and inhibited Keap1 expression (1.1±0.6, P=0.02). Furthermore, as compared to control diabetic rats, CoQ-10 ameliorated oxidative stress by decreasing malondialdehyde levels and increasing catalase, glutathione peroxidase activities, and glutathione levels in the liver tissues of the treated rats in the treatment group. The findings of this study revealed that CoQ-10 could increase the antioxidant capacity of the liver tissue in diabetic rats by modulating the Nrf2/Keap1/HO-1/NQO1 signaling pathway.

Extreme heat event influences the toxic impacts of nano-TiO2 with different crystal structures in mussel Mytilus coruscus

The wide use of nano‑titanium dioxide (nano-TiO2) and its ubiquitous emission into aquatic environments are threatening environmental health. Ambient temperature can affect the aggregation state of nano-TiO2 in seawater, thus influencing the intake and physiological effects on marine species. We studied the physiological effects of mixed nano-TiO2 (a mixture of anatase crystal and rutile crystal with an average particle size of 25 nm, P25) on mussels. Subsequently, we investigated the oxidative stress, immunotoxicity, neurotoxicity, and detoxification in Mytilus coruscus exposed to two different crystal structures of nano-TiO2 (anatase and rutile) at 100 μg/L concentration under marine heatwaves (MHWs, 28 °C). MHWs and nano-TiO2 exposure induced neurotoxicity and immune damage and caused dysregulation of redox balance in the gills. Moreover, MHWs exposure disturbed the glutathione system and detoxification function of mussels, resulting in enhanced toxicity of nano-TiO2 after co-exposure. Anatase exposure significantly impaired the antioxidative system and downregulated the relative expression of antioxidant-related genes (Nrf2 and Bcl-2), HSP-90, and immune parameters under MHWs, while producing higher ROS levels compared to rutile. Based on integrated biomarker response (IBR), anatase combined with MHWs group showed the highest value (19.29). However, there was no significant difference in bioaccumulation of titanium between anatase (6.07 ± 0.47 μg/g) and rutile (5.3 ± 0.44 μg/g) exposures under MHWs. These results indicate that MHWs would elevate the potential hazard of nanoparticles to marine organisms.

Selenomethionine and Allicin Synergistically Mitigate Intestinal Oxidative Injury by Activating the Nrf2 Pathway.

Oxidative stress frequently contributes to intestinal barrier injury in animals and humans. It was reported that both Selenomethionine (SeMet) and allicin exhibit protective effects against a range of diseases caused by oxidative stress. This study aimed to investigate the synergistic antioxidant effects and underlying mechanisms of SeMet and allicin on a H2O2-induced intestinal barrier injury model using IPEC-J2 cells and mice. The results showed that H2O2 induced severe oxidative stress, including a decrease in cell viability, antioxidant level, migration capacity, and cell integrity. SeMet and allicin exhibited significant synergistic anti-oxidative effects on intestinal epithelial cells. The combined use of SeMet and allicin increased SOD activity, GSH content, and GSH/GSSG ratio while decreasing MDA, NO, and ROS content levels. Furthermore, we found that SeMet and allicin synergistically activated the nuclear factor erythroid-related factor 2 (Nrf2)-NAD(P)H dehydrogenase [quinone] 1 (NQO1) signaling pathway and down-regulated endoplasmic reticulum stress (ER stress)-related proteins. However, the synergistic antioxidative and intestinal barrier protective effects of SeMet and allicin were abolished by Nrf2 inhibitor ML385 in vitro and in vivo. In conclusion, SeMet and allicin synergistically attenuate intestinal barrier injury induced by excessively oxidative stress through the activation of the Nrf2 signaling pathway and inhibition ER stress. These findings support that the combined use of SeMet and allicin could enhance antioxidative properties and alleviate intestinal injury in further clinical practice.

Self-cascade ROS-trapping bioreaction system reverses stem cell oxidative stress fate for osteogenesis

eactive oxygen species (ROS) scavenging is essential for periodontal regeneration. However, the dynamic change of the applied materials within the ROS-rich environment and the residual oxidation products in the host highly impact periodontal regeneration. This study successfully constructs a bioreaction system via thiol-ene click chemistry, leveraging the high affinity of glutathione (GSH) for ROS to attract excess ROS to the crosslinking points. Two minutes after hydrogen peroxide (H2O2) treatment, the ROS level in the G8-0 hydrogel acutely decreases, reaching a 4.4% reduction within 10minutes, confirming the ROS-trapping efficacy. Through a ‘bait switch-on’ mechanism, hexagonal boron nitride (hBN) takes over the captured ROS and the oxidation products of pectin further drive the reduction reaction, ultimately restoring the extracellular environment. The self-cascade products, oxidized hBN, reshape the intracellular oxidative stress (OS) environment, achieving a synergistic extra- and intra-cellular treatment. The significantly high reduced to oxidized glutathione (GSH/GSSG) ratio in G8-10 hydrogel (~80%) illustrates a reversal of oxidative stress in bone marrow stem cells (BMSCs). On a molecular level, the bioreaction system inhibits the NF-κB pathway, promoting the expression of key antioxidant genes (Nqo1 and Nrf2) and osteogenic molecules (ALP and OCN), thereby reversing the detrimental effects of OS on BMSCs. In vivo application demonstrated the system’s strong redox-balancing and osteogenic capabilities in the periodontal inflammation environment. This novel antioxidant bioreaction system, characterized by self-cascade ROS-trapping and product utilization, offers innovative treatment strategies for tissue regeneration under conditions of excessive OS.

Dietary lecithin attenuates adverse effects of high fat diet on growth performance, lipid metabolism, endoplasmic reticulum stress and antioxidant capacity in the intestine of largemouth bass (Micropterus salmoides)

This study was conducted to investigate the effects of dietary lipid and lecithin levels on growth performance, lipid metabolism, endoplasmic reticulum stress and antioxidant capacity in intestinal tissues of largemouth bass (Micropterus salmoides). Five experimental diets include the control (10.67 % lipid, normal dietary lipid without extra lecithin addition), 1.0 g/kg lecithin diet with normal dietary lipid level (Lec diet, 10.94 % lipid), high fat diet without extra lecithin addition (HFD, 18.65 % lipid), and HFD supplemented with 1.0 g/kg and 2.0 g/kg lecithin (HFD + Lec1 and HFD + Lec2 diets, respectively). Largemouth bass (initial body weight: 5.39 ± 0.04 g/fish) were fed five diets for 10 weeks. Dietary lecithin alleviated the growth retardation and intestinal damage induced by HFD. HFD-induced increase of whole body and intestinal crude lipid contents and decline of intestinal poly-unsaturated fatty acids content were also alleviated by dietary lecithin addition. Dietary lecithin alleviated the increase of TG content, activities of lipogenic enzymes (G6PD, 6PGD, ME, ICDH and FAS), mRNA expression of lipogenic genes (g6pd, 6pgd, fas, accα, dgat1, dgat2 and srebp1) and protein expression of Srebp1, and downregulation of mRNA expression of lipolytic gene cpt1) and protein expression of Pparα induced by HFD. Lecithin addition mitigated the up-regulation of mRNA expression of lipid absorption genes (fabp2, fatp4, sr-1b and npc1l1), and the down-regulation of mRNA expression of chylomicron assembly- and secretion-relevant genes (mttp and acat2) and proteins (Mttp, Apob and Sar1b), chylomicron components (TG, phosphatidylcholine and apolipoprotein) and MTTP activity induced by HFD. Compared with HFD, HFD + Lec1 diet significantly decreased the mRNA expression of endoplasmic reticulum (ER) stress genes (grp94, grp78, calr, chop, ire1α and xbp1) and Grp78 protein expression. Compared with HFD, the activities of antioxidant enzymes (CAT, T-SOD and GPx) and mRNA expression of genes (sod1, cat, gpx1 and nrf2) were significantly increased but MDA content and keap1 mRNA expression were significantly decreased in HFD supplemented with 1.0 g/kg and 2.0 g/kg lecithin. These results indicated that dietary lecithin supplementation increased growth rate, improved lipid metabolism, relieved ER stress, and enhanced antioxidant capacity, thereby alleviating negative effects of HFD on the function and health of intestinal tract of largemouth bass. Statement of relevanceOur results found that dietary addition of lecithin has obvious merits in alleviating negative effects of HFD on the intestinal function and health, which provided good basis for lecithin addition in aquafeeds.

Specific cancer types and prognosis in patients with variations in the KEAP1-NRF2 system: A retrospective cohort study.

The KEAP1-NRF2 system induces the expression of antioxidant genes in response to various types of oxidative stress. Some cancer cells activate this system, which increases their malignancy through genetic mutations. We performed a retrospective cohort study using the C-CAT database, which contains the gene-panel sequence data from 60,056 cases of diagnosed solid tumors. We analyzed somatic mutations in NRF2 and KEAP1 genes and their associations with clinical outcomes. Variants in the NRF2 gene were clustered in exon 2, which encodes the DLG and ETGE motifs essential for KEAP1 interaction. The NRF2 variants were frequently observed in esophageal and lung squamous cell carcinoma with frequencies of 35.9% and 19.6%, respectively. Among these mutations, the NRF2 variants in the ETGE motif were indicators of a worse prognosis. KEAP1 variants were found in 2.5% of all cases. The variants were frequent in lung cancer and showed a worse prognosis in lung and other types of adenocarcinomas. We then conducted gene expression analysis using TCGA data. While cancers with DLG and ETGE variants were similar in terms of gene expression profiles, there were significant differences between cancers with KEAP1 and NRF2 variants. Our results indicate that genetic alteration of the KEAP1-NRF2 pathway is a major factor in patient prognosis for each cancer type and its genetic variant. Variants in NRF2 and KEAP1 genes can characterize the biological basis of each cancer type and are involved in carcinogenesis, resistance to therapy, and other biological differences.

Supplementing ageing male laying breeders with lycopene alleviates oxidative stress in testis and improves testosterone secretion

BackgroundReproductive performance is a crucial aspect of poultry production and is carefully controlled by endocrine, paracrine, and autocrine factors. This study aimed to investigate the effect of lycopene on testosterone synthesis in Leydig cells of laying breeder roosters, clarify the mechanism of lycopene improving Leydig cells function and promoting testosterone production, and explore the role of related signal transduction pathways in testosterone synthesis. ResultsA total of 96 healthy 55-week-old breeding roosters were randomly assigned to one of five dietary treatments. They were provided with a corn-soybean meal-based diet containing different levels of lycopene: 0 mg/kg (control), 50 mg/kg, 100 mg/kg, or 200 mg/kg. The experiment lasted for 6 weeks. With the increase in lycopene levels, the testosterone content in the plasma was significantly higher than in the control group. Testicular Leydig cells were isolated and cultured from fresh testicular tissue of 45-wk-old to 60-wk-old breeding roosters. Various doses of lycopene were administered to Leydig cells, and subsequently, cells were collected for the detection of cell viability and testosterone content. The optimal concentration of lycopene to be added was determined, and changes in mRNA expression and protein levels of key proteins involved in testosterone synthesis were investigated. The results showed that lycopene treatment significantly increased testosterone secretion, mRNA expression, and protein levels of steroid-producing enzymes. Cells were collected to measure the activity of antioxidant enzymes, the mRNA transcription level of apoptotic factors, and the protein expression of apoptotic factors after treatment with lycopene. The results showed that lycopene significantly increased the activities of antioxidant enzymes, and the ability to inhibit oxygen radicals, and decreased the content of malondialdehyde. Apoptosis was inhibited by regulating the expression of apoptosis-inducing and anti-apoptosis factors. After that, the MAPK signaling pathway and downstream SF-1, Nrf2 gene, and protein expression levels were detected. The results showed that lycopene treatment significantly increased the gene and protein expression of JNK, SF-1, and Nrf2, and significantly decreased the gene and protein expression of p38. ConclusionsLycopene treatment could promote testosterone synthesis of testicular Leydig cells by activating MAPK-SF-1 (increasing steroid-producing enzyme level) and MAPK-Nrf2 pathways (resisting oxidative damage).

Potential of NRF2 Inhibitors-Retinoic Acid, K67, and ML-385-In Overcoming Doxorubicin Resistance in Promyelocytic Leukemia Cells.

Drug resistance is one of the major obstacles to the clinical use of doxorubicin, an extensively used chemotherapeutic drug to treat various cancers, including leukemia. Inhibition of the nuclear factor erythroid 2-related factor 2 (NRF2) seems a promising strategy to reverse chemoresistance in cancer cells. NRF2 is a transcription factor that regulates both antioxidant defense and drug detoxification mechanisms. In this study, we investigated the potential of three inhibitors of NRF2-K67, retinoic acid and ML-385-to overcome doxorubicin resistance in promyelocytic leukemia HL-60 cells. For this purpose, low-dose doxorubicin was used to establish doxorubicin-resistant HL-60/DR cells. The expression of NRF2 and its main repressor, Kelch-like ECH-associated protein 1 (KEAP1), at mRNA and protein levels was examined. HL-60/DR cells overexpressed NRF2 at mRNA and protein levels and down-regulated KEAP1 protein compared to drug-sensitive HL-60 cells. The effects of NRF2 inhibitors on doxorubicin-resistant HL-60/DR cell viability, apoptosis, and intracellular reactive oxygen species (ROS) levels were analyzed. We observed that NRF2 inhibitors significantly sensitized doxorubicin-resistant HL-60/DR cells to doxorubicin, which was associated with increased intracellular ROS levels and the expression of CAS-9, suggesting the participation of the mitochondrial-dependent apoptosis pathway. Furthermore, ML-385 inhibitor was used to study the expression of NRF2-KEAP1 pathway genes. NRF2 gene and protein expression remained unchanged; however, we noted the down-regulation of KEAP1 protein upon ML-385 treatment. Additionally, the expression of NRF2-regulated antioxidant and detoxification genes including SOD2, HMOX2, and GSS was maintained upon ML-385 treatment. In conclusion, our results demonstrated that all the studied inhibitors, namely K67, retinoic acid, and ML-385, increased the efficacy of doxorubicin in doxorubicin-resistant HL-60/DR cells, and suggested a potential strategy of combination therapy using NRF2 inhibitors and doxorubicin in overcoming doxorubicin resistance in leukemia.

Genetic Variations in the NRF2 Microsatellite Contribute to the Regulation of Bovine Sperm-Borne Antioxidant Capacity.

Nuclear factor (erythroid-derived 2)-like 2 (NRF2) is a transcription factor protein-coding gene, considered a master regulator of the cellular stress response. The genetic variations of the NRF2 could influence its transcriptional profile and, subsequently, the stress resilience in all cell types, including sperm cells. Therefore, the sperm-borne antioxidants abundance in association with the genetic variation of a GCC microsatellite located at the 5' upstream region of the NRF2 gene was investigated in young (n = 8) and old (n = 8) Holstein bulls' sperm cells at different seasons. The sperm DNA was sequenced using Sanger sequencing, while- the sperm-borne mRNA analysis was carried out using the synthesized cDNA and qPCR. The data were statistically analyzed using GraphPad Prism 10.0.2 software. The results showed that two bulls had a heterozygous genotype of eight and nine GCC repeats, while biallelic of eight, nine, and fifteen repeats were identified in two, ten, and two bulls, respectively. The computational in silico analysis revealed that the NRF2 upstream sequence with 15, 9, and 8 GCC repeats bound with 725, 709, and 707 DNA-binding transcription factor proteins, respectively. Lower quality of sperm DNA was detected in the spring season compared to other seasons and in young bulls compared to old ones, particularly in the summer and autumn seasons. The mRNA expression analysis revealed that the PRDX1 gene was the abundant transcript among the studied sperm-borne antioxidants and was significantly determined in old bulls' spermatozoa. Moreover, two transcripts of the NRF2 gene and antioxidant (SOD1, CAT, GPX1, TXN1, NQO1) genes displayed differential expression patterns between the age groups across seasons in an antioxidant-dependent manner. The bulls with a heterozygous GCC sequence exhibited elevated sperm-borne mRNA levels of NRF2 and PRDX1 transcripts. Taken together, the findings suggest that the NRF2-GCC microsatellite may contribute to the transcription regulation of NRF2 transcripts and their subsequent downstream antioxidants in bovine sperm cells.

The Potential of Human Pulmonary Mesenchymal Stem Cells as Vectors for Radiosensitizing Metallic Nanoparticles: An In Vitro Study.

Metallic nanoparticles (NPs) exhibit interesting radiosensitizing effects, and finding a way to accurately deliver them appears to be crucial. Due to their tumor tropism, mesenchymal stem cells (MSCs) represent a strategic approach. Therefore, we aimed to evaluate the impact of core-shell Fe3O4@Au NPs on the functionality of human pulmonary MSCs (HPMSCs). The results showed that 100 µg/mL Fe3O4@Au NPs, accumulated in HPMSCs (revealed by Prussian blue staining), did not alter cell viability as assessed by cell counting, MTT, and LDH assays. However, caspase 9 and Bcl2 gene expression, evaluated by RT-qPCR, was regulated 72 h after exposure to the NPs. Moreover, the NPs also decreased proinflammatory cytokine/chemokine secretions, except for CXCL8 (ELISA). These modulations were associated with the downregulation of AMPK gene expression at 24 h. In contrast, the NPs did not modulate VEGF, PI3K, or PDGF gene expression. Nevertheless, a decrease in VEGF secretion was observed after 24 h of exposure to the NPs. Interestingly, the Fe3O4@Au NPs did not modulate Nrf2 gene expression, but they did regulate the expression of the genes encoding Nox4 and HMOX-1. Additionally, the NPs increased ROS production, suggesting a redox imbalance. Finally, the Fe3O4@Au NPs did not affect the HPMSCs' viability or proangiogenic/tumorigenic markers. These findings are encouraging for investigating the effects of Fe3O4@Au NPs delivered by HPMSCs to tumor sites in combination with radiation.