Nrf2/Keap1/ARE signaling: Towards specific regulation

Modulation of NF-κB/Nrf2 signaling by nobiletin mitigates airway inflammation and oxidative stress in PM2.5-exposed asthmatic mice

Exposure to fine particulate matter (PM2.5) is a significant risk factor for asthma, promoting airway inflammation and oxidative stress. This study evaluates Nobiletin's (NOB) efficacy in mitigating airway inflammation and oxidative lung damage in asthma-induced mice exposed to PM2.5. Using an ovalbumin (OVA) plus PM2.5-induced asthma model in BALB/c mice, we investigated the therapeutic impacts of NOB compared to dexamethasone (DEX). NOB significantly moderated lung index values and inflammatory markers without affecting body weight. Notably, NOB enhanced Nrf2 expression and decreased NF-κB-p65, IKK, and Keap-1 levels, aligning with reductions in malondialdehyde (MDA) and reactive oxygen species (ROS) while increasing superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. These findings suggest that NOB can effectively reduce airway inflammation and oxidative lung damage by modulating the NF-κB/Nrf2 signaling pathways.

IRG1/itaconate enhances efferocytosis by activating Nrf2-TIM4 signaling pathway to alleviate con A induced autoimmune liver injury

Immune response gene 1 (IRG1) is highly expressed in mitochondria of macrophages in a pro-inflammatory state. IRG1 and its metabolites play important roles in infection, immune-related diseases and tumor progression by exerting resistance of pathogens, attenuating inflammation and producing antioxidant substances through various pathways and mechanisms. IRG1 deficiency aggravates liver injury. Efferocytosis is a vital mechanism for preventing the progression of inflammatory tissue damage. However, the mechanism by how IRG1/itaconate regulates efferocytosis in autoimmune hepatitis has yet to be fully understood. Therefore, we explored the influence of IRG1-/- on efferocytosis and its effects on regulating the nuclear factor erythroid 2-associated factor 2 (Nrf2)-T-cell immunoglobulin domain and mucin domain 4 (TIM4) pathway and autoimmune liver injury. An autoimmune hepatitis model was established by injecting Con A into wild-type and IRG1-/- mice via the tail vein. Liver injury and inflammatory response were assessed. The efferocytosis role of IRG1-/- macrophages and its potential regulatory mechanisms were also analysed. Exogenous 4-octyl itaconate (OI) supplementation promoted the expression of Nrf2 and TIM4 and restored IRG1-/- bone marrow-derived macrophage (BMDM) efferocytosis, whereas inhibition of Nrf2 mediated by ML385 led to impaired efferocytosis of BMDMs, decreased expression of TIM4, and aggravated liver inflammation injury. Additionally, after supplementing Nrf2-/- BMDMs with exogenous OI, we evaluated the changes in its efferocytosis effect, efferocytosis did not change, and the protective effect of OI disappeared. However, when TIM4 was blocked, the efferocytotic effect of BMDMs was attenuated, inflammatory liver injury and oxidative stress were aggravated. OI promoted the transformation of macrophages into M2 macrophages, and this was inhibited when TIM4 was blocked. To our best understanding, this is the initial exploration to show that TIM4, a downstream molecule of the IRG1/itaconate-Nrf2 pathway, regulates macrophage efferocytosis. These findings suggest a new mechanism and potential treatment for promoting the resolution of inflammation and efferocytosis in autoimmune hepatitis.

Regulatory mechanisms of the probiotic-targeted gut-liver axis for the alleviation of alcohol-related liver disease: a review

Alcohol abuse-triggered alcohol-related liver disease (ALD) has become as a global public health concern that substantially affects the well-being and clinical status of patients. Although modern medicine provides various treatments for ALD, their effectiveness is limited and can lead to adverse side effects. Probiotics have been employed to prevent, alleviate, and even treat ALD, with promising results. However, few comprehensive reviews are available on how they mitigate ALD by targeting the gut-liver axis. This review systematically clarifies the specific mediators of the gut-liver axis in healthy states. It also describes the alterations observed in ALD. Furthermore, this review thoroughly summarizes the underlying mechanisms through which probiotics act on the gut-liver axis to relieve ALD. It also discusses the current status and challenges faced in clinical research applications. Finally, we discuss the challenges and future prospects of using probiotics to treat ALD. This review improves our understanding of ALD and supports the development and application of probiotics that target the gut-liver axis for therapeutic use.

Chemical proteomic profiling reveals prostaglandin termination enzyme PTGR2 as a key molecular target of natural coumarin fraxetin

Natural coumarins represent a diverse group of secondary metabolites with a wide range of biological activities. However, their specific molecular targets have remained largely unexplored. Employing chemical proteomics, a comprehensive analysis of the protein targets of the natural coumarin fraxetin has been conducted. Prostaglandin reductase 2 (PTGR2), a key enzyme involved in the final inactivation of prostaglandins, was identified as a primary target of fraxetin. Inhibition of PTGR2 can lead to the accumulation of 15-keto-PGE2, which subsequently activates the Nrf2 signaling pathway and suppresses NF-κB, resulting in notable anti-inflammatory effects. These findings provide novel insights into the molecular targets of fraxetin and other coumarins, which are crucial for fully exploring their therapeutic potential.

Cigarette Smoke Contributes to the Progression of MASLD: From the Molecular Mechanisms to Therapy

Cigarette smoke (CS), an intricate blend comprising over 4000 compounds, induces abnormal cellular reactions that harm multiple tissues. Non-alcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disease (CLD), encompassing non-alcoholic fatty liver (NAFL), non-alcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma (HCC). Recently, the term NAFLD has been changed to metabolic dysfunction-associated steatotic liver disease (MASLD), and NASH has been renamed metabolic dysfunction-associated steatohepatitis (MASH). A multitude of experiments have confirmed the association between CS and the incidence and progression of MASLD. However, the specific signaling pathways involved need to be updated with new scientific discoveries. CS exposure can disrupt lipid metabolism, induce inflammation and apoptosis, and stimulate liver fibrosis through multiple signaling pathways that promote the progression of MASLD. Currently, there is no officially approved efficacious pharmaceutical intervention in clinical practice. Therefore, lifestyle modifications have emerged as the primary therapeutic approach for managing MASLD. Smoking cessation and the application of a series of natural ingredients have been shown to ameliorate pathological changes in the liver induced by CS, potentially serving as an effective approach to decelerating MASLD development. This article aims to elucidate the specific signaling pathways through which smoking promotes MASLD, while summarizing the reversal factors identified in recent studies, thereby offering novel insights for future research on and the treatment of MASLD.

Angel or devil: the dual roles of 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucopyranoside in the development of liver injury based on integrating pharmacological techniques: a systematic review

Background and purpose

2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside (TSG) exhibits a dualistic pharmacological profile, acting as both a hepatoprotective and hepatotoxic agent, which is intricately linked to its interaction with multiple signaling pathways and its stereoisomeric forms, namely, cis-SG and trans-SG. The purpose of this study is to evaluate both the hepatoprotective and hepatotoxic effects of TSG and give therapeutic guidance.

Methods

This study performed a systematic search of eight databases to identify preclinical literature up until March 2024. The CAMARADES system evaluated evidence quality and bias. STATA and Python were used for statistical analysis, including dose-effect maps, 3D maps and radar charts to show the dose-time-effect relationship of TSG on hepatoprotection and hepatotoxicity.

Results

After a rigorous screening process, a total of 24 studies encompassing 564 rodents were selected for inclusion in this study. The findings revealed that TSG exhibited bidirectional effects on the levels of ALT and AST, while also regulating the levels of ALT, AST, TNF-α, IL-6, serum TG, serum TC, SOD, MDA, IFN-γ, and apoptosis rate. The histological analysis of liver tissue confirmed the regulatory effects of TSG, and a comprehensive analysis revealed the optimal protective dosage range was 27.27-38.81 mg/kg/d and the optimal toxic dosage range was 51.93-76.07 mg/kg/d. TSG exerts the dual effects on liver injury (LI) through the network of Keap1/Nrf2/HO-1/NQO1, NF-κB, PPAR, PI3K/Akt, JAK/STAT and TGF-β pathways.

Conclusion

TSG could mediate the pathways of oxidation, inflammation, and metabolism to result in hepatoprotection (27.27-38.81 mg/kg/d) and hepatotoxicity (51.93-76.07 mg/kg/d).

Nrf2 signaling pathway studies in Drosophila melanogaster: parallel roles in human health and insect environmental responses

The Nrf2 signalling pathway is crucial for cellular defense against oxidative stress and xenobiotic toxicity, highlighting its importance in both human health and environmental responses.This review focuses on the dual role of Drosophila melanogaster in Nrf2 research: we utilised the PubMed database to collect and summarised research articles on fruit fly Nrf2 studies published in the past decade, using keywords such as 'Nrf2', 'CncC', and 'Drosophila'.We found that Drosophila melanogaster, as a classical model organism for studying human diseases such as neurodegenerative disorders, cancers, and diabetes, and as an insect model for investigating xenobiotic responses and pesticide resistance, is particularly well-suited for exploring the diverse and complex functions of Nrf2 pathway.Additionally, Natural products such as curcumin and quercetin can modulate Nrf2 activity for cytoprotection. Utilising D. melanogaster's genetic tools and short life cycles, researchers can discover new therapeutics and study their mechanisms.This twofold exploration not only advances our understanding of Nrf2 in human health but also provides insights into pest control strategies through enhanced insect resistance mechanisms. Continued research in this area is essential for developing innovative treatments and effective pest management approaches.

Lycopene Ameliorates Polycystic Ovary Syndrome in Rats by Inhibiting Ovarian Ferroptosis Through Activation of the AMPK/Nrf2 Pathway

Lycopene (LYC) is an extremely powerful antioxidant with the potential to treat a range of diseases and to inhibit ferroptosis. This research aims to elucidate how LYC impacts polycystic ovarian syndrome (PCOS) and the action mechanisms. A PCOS rat model was constructed by injecting DHEA. Different doses of LYC were injected intraperitoneally in PCOS rats, the estrous cycle was recorded. The histopathological damage of ovary in PCOS rats was observed by HE staining, testosterone (T), estradiol (E2), luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels were examined by ELISA kits. Transmission electron microscopy, prussian blue staining, biochemical kits to determine ferroptosis. Immunohistochemistry and Western blot to assess the levels of ferroptosis-related and AMPK/Nrf2 pathway-related proteins to explore whether LYC affects ferroptosis in PCOS through this pathway. PCOS rats had significantly higher body weights, ovarian weights and ovarian indices, and disorganized estrous cycles, which were dose-dependently ameliorated by LYC. In addition, LYC significantly ameliorated the histopathological damage of ovary in PCOS rats and restored the normal secretion of T, E2, LH, and FSH. LYC attenuates iron deposition in PCOS ovarian tissues, reduces iron and ROS levels, and inhibits ferroptosis. Notably, LYC activated the AMPK/Nrf2 pathway, and AMPK inhibitor intervention attenuated the therapeutic effect of LYC in PCOS rats, suggesting that LYC acts through the AMPK/Nrf2 pathway. LYC attenuates estrous cycle disruption, ameliorates pathological impairments, and inhibits ferroptosis in PCOS rats by modulating the AMPK/Nrf2 pathway.

Nigella sativa L. seed extract alleviates oxidative stress-induced cellular senescence and dysfunction in melanocytes

Nigella sativa L. seeds have been traditionally utilized in Chinese folk medicine for centuries to treat vitiligo. This study revealed that the ethanolic extract of Nigella sativa L. (HZC) enhances melanogenesis and mitigates oxidative stress-induced cellular senescence and dysfunction in melanocytes. In accordance with established protocols, the ethanol fraction from Nigella sativa L. seeds was extracted, concentrated, and lyophilized to evaluate its herbal effects via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, tyrosinase activity evaluation, measurement of cellular melanin contents, scratch assays, senescence-associated β-galactosidase (SA-β-gal) staining, enzyme-linked immunosorbent assay (ELISA), and Western blot analysis for expression profiling of experimentally relevant proteins. The results indicated that HZC significantly enhanced tyrosinase activity and melanin content while notably increasing the protein expression levels of Tyr, Mitf, and gp100 in B16F10 cells. Furthermore, HZC effectively mitigated oxidative stress-induced cellular senescence, improved melanocyte condition, and rectified various functional impairments associated with melanocyte dysfunction. These findings suggest that HZC increases melanin synthesis in melanocytes through the activation of the MAPK, PKA, and Wnt signaling pathways. In addition, HZC attenuates oxidative damage induced by H2O2 therapy by activating the nuclear factor E2-related factor 2-antioxidant response element (Nrf2-ARE) pathway and enhancing the activity of downstream antioxidant enzymes, thus preventing premature senescence and dysfunction in melanocytes.

Neochlorogenic acid ameliorates allergic airway inflammation by suppressing type 2 immunity and upregulating HO-1 expression

Neochlorogenic acid is a natural compound isolated from various fruits and vegetables that has anti-inflammation and anti-oxidative effects in macrophages. Inflammatory immune cells and tracheal epithelial cells can stimulate airway hyperresponsiveness, inflammation, and reactive oxygen species. In this study, we investigated the effect of neochlorogenic acid in ameliorating inflammatory and oxidative responses in asthmatic mice. We used an ovalbumin (OVA)-induced mouse model, treating mice with neochlorogenic acid by intraperitoneal injection. We also treated inflammatory human tracheal epithelial (BEAS-2B) cells with neochlorogenic acid to evaluate inflammatory cytokine levels and oxidative responses. The results demonstrate that neochlorogenic acid attenuated airway hyperresponsiveness, eosinophil infiltration, and goblet cell hyperplasia in the lungs of asthmatic mice. Neochlorogenic acid also reduced type 2 cytokine expression in bronchoalveolar lavage fluid and improved oxidative stress in the lung. Neochlorogenic acid effectively blocked monocyte attachment to adherent BEAS-2B cells, and reduced pro-inflammatory cytokine and reactive oxygen species production in inflammatory BEAS-2B cells. These findings suggest that neochlorogenic acid is a potential immunomodulator that can ameliorate airway hyperresponsiveness and airway inflammation in asthmatic mice.

Gentisic acid attenuates ovalbumin-induced airway inflammation, oxidative stress, and ferroptosis through the modulation of Nrf2/HO-1 and NF-κB signaling pathways

Asthma, a lung disorder that causes impaired respiratory function, is characterized by an apparent infiltration of inflammatory cells. Gentisic acid (GA), a phenolic acid common in food ingredients, has antioxidant, antibacterial, and anti-inflammatory properties. Its potential application in mitigating asthma, however, remains unexplored. The current investigation studies GA's therapeutic potential for allergic asthma. BALB/c mice were challenged and sensitized to ovalbumin (OVA) to establish the animal model. We investigated how GA affected asthmatic behavior, leukocyte infiltration, histopathological alterations, oxidative stress, immunoglobulin E (IgE) production, and airway inflammation. ELISA and immunohistochemistry (IHC) techniques were employed to measure Nrf2, HO-1, and NF-κB's expression. To investigate the protein-ligand interaction between GA and Keap1, molecular docking analysis was utilized. The GA treatment significantly reduced nasal scratching, oxidative stress in the lungs, the infiltration of inflammatory cells, IgE content, iron accumulation, and NF-κB activation. It also upregulated Nrf2 and HO-1. Additionally, in silico studies revealed GA and Keap1 binding to activate Nrf2 by disrupting the Keap1-Nrf2 interaction. The study at hand is the first to investigate and report on the immunomodulatory impacts of GA on induced asthma in BALB/c mice. Our findings reveal that GA can be utilized as an anti-asthmatic agent via Nrf2/HO-1 and NF-κB pathway regulation.

Antioxidant-Rich Functional Foods and Exercise: Unlocking Metabolic Health Through Nrf2 and Related Pathways

This article reviews the synergistic effects of antioxidant-enriched functional foods and exercise in improving metabolic health, focusing on the underlying molecular mechanisms. The review incorporates evidence from PubMed, SCOPUS, Web of Science, PsycINFO, and reference lists of relevant reviews up to 20 December 2024, highlighting the central role of the Nrf2 pathway. As a critical regulator of oxidative stress and metabolic adaptation, Nrf2 mediates the benefits of these interventions. This article presents an innovative approach to understanding the role of Nrf2 in the regulation of oxidative stress and inflammation, highlighting its potential in the prevention and treatment of various diseases, including cancer, neurodegenerative disorders, cardiovascular and pulmonary diseases, diabetes, inflammatory conditions, ageing, and infections such as COVID-19. The novelty of this study is to investigate the synergistic effects of bioactive compounds found in functional foods (such as polyphenols, flavonoids, and vitamins) and exercise-induced oxidative stress on the activation of the Nrf2 pathway. This combined approach reveals their potential to improve insulin sensitivity and lipid metabolism and reduce inflammation, offering a promising strategy for the management of chronic diseases. However, there are significant gaps in current research, particularly regarding the molecular mechanisms underlying the interaction between diet, physical activity, and Nrf2 activation, as well as their long-term effects in different populations, including those with chronic diseases. In addition, the interactions between Nrf2 and other critical signalling pathways, including AMPK, NF-κB, and PI3K/Akt, and their collective contributions to metabolic health are explored. Furthermore, novel biomarkers are presented to assess the impact of these synergistic strategies, such as the NAD+/NADH ratio, the GSH ratio, and markers of mitochondrial health. The findings provide valuable insights into how the integration of an antioxidant-rich diet and regular exercise can improve metabolic health by activating Nrf2 and related molecular pathways and represent promising strategies for the prevention and treatment of metabolic disorders. Further studies are needed to fully understand the therapeutic potential of these interventions in diseases related to oxidative stress, such as cardiovascular disease, neurodegenerative disease, diabetes, and cancer.

Kurarinone Mitigates LPS-Induced Inflammatory Osteolysis by Inhibiting Osteoclastogenesis Through the Reduction of ROS Levels and Suppression of the PI3K/AKT Signaling Pathway

Inflammatory bone resorption represents a pathological condition marked by an increase in bone loss, commonly associated with chronic inflammatory conditions such as rheumatoid arthritis and periodontitis. Current therapies primarily focus on anti-inflammatory drugs and bisphosphonates; however, these treatments are limited due to side effects, inadequate efficacy, and unpredictable long-term complications. Kurarinone (KR), a bioactive compound isolated from the traditional Chinese herb Sophora flavescens, exhibits a range of biological activities, including anti-inflammatory, anticancer, and cardiovascular protective effects. To address the limitations of existing therapies and enhance drug utilization, this study explores the potential of KR as a therapeutic agent for inflammatory bone resorption and delineates its underlying mechanisms. In vitro experiments reveal that KR notably inhibits osteoclastogenesis and reduces the expression of osteoclastic markers. Additionally, KR decreases the levels of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α, while downregulating NADPH oxidase 1 (NOX1) and Kelch-like ECH-associated protein 1 (Keap1) to diminish ROS production. Furthermore, KR activates the nuclear factor erythroid 2-related factor 2 (Nrf2), which enhances the activity of heme oxygenase-1 (HO-1) and catalase (CAT), facilitating the clearance of excess ROS. The compound also hinders osteoclast formation and functionality by inhibiting the PI3K/AKT/GSK-3β signaling pathway. Lentiviral knockdown of CAT can partially reverse these effects of KR. Meanwhile, in vivo experiments indicate that KR effectively mitigates bone loss in an LPS-induced inflammatory bone resorption model. In summary, KR is a promising new star in breaking through the limitations of previous drugs and treating inflammatory bone resorption.

The total extract of Abelmoschus manihot (L.) medic flowers (TEA) mediated Nrf2-TFAM signalling to regulate mitochondrial antioxidant mechanism

Skin, as the first line of defence of the human body, is exposed to dangers such as overheating substances, ultraviolet rays, and environmental pollutants, and the incidence of skin diseases is increasing annually. Oxidative stress plays a dominant role in most skin diseases. Abelmoschus manihot (L.) medic flower (TEA) is a traditional Chinese medicine widely used to treat injuries to the skin such as water and fire scalds. It has been reported that TEA has excellent antioxidant effects. In this study, we aimed to explore the antioxidant and mitochondrial protection effects of TEA in H2O2-mediated HaCaT cell damage. HaCaT cells were incubated with H2O2 to simulate oxidative stress in the skin. The effect of TEA on HaCaT cells was also evaluated. Cell morphology was observed via inverted microscopy, and cell viability was measured via the MTT reagent. The cells were stained with Hoechst 33,324 solution. Reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA) and ATP detection kits were used to detect the corresponding indicators. The mitochondrial membrane potential was detected by JC-1. RT-PCR was used to detect mRNA and mtDNA expression. The expression of the target protein was detected by Western blotting and immunofluorescence. H2O2 triggered oxidative damage in HaCaT cells, which manifested as apoptosis, increased ROS and MDA contents, and decreased SOD activity. H2O2 activates the KEAP1/Nrf2/NQO1 signalling pathway, which decreases the expression of the intracellular KEAP1 protein and slightly increases the expression of the Nrf2 and NQO1 proteins, further causing mitochondrial oxidative stress, resulting in changes in the mitochondrial membrane potential, a reduction in the mtDNA copy number, and decreased expression of the PGC-1α and TFAM proteins. In addition the expression of mitochondrial respiratory chain genes and proteins decreased. TEA promoted the expression of Nrf2 in HaCaT cells, activated the downstream antioxidant response, and alleviated the oxidative stress and mitochondrial damage caused by H2O2. ML385 is an Nrf2 inhibitor, under which the antioxidant and mitochondrial protective effects of TEA are inhibited. When TFAM was knocked down, the protective effect of TEA on mitochondria was also inhibited. TEA protects HaCaT cells from H2O2-induced oxidative damage and mitochondrial oxidative damage through the KEAP1/Nrf2/NQO1/PGC-1α/TFAM pathway.

Oxyberberine alleviates lipopolysaccharide-induced intestinal barrier disruption and inflammation in human colonic Caco-2 cells in vitro

Background

Oxyberberine (OBB) is a naturally occurring isoquinoline alkaloid that is believed to possess various health-promoting properties, including anti-fungus, hepatoprotection, anti-inflammation, and anti-intestinal mucositis effects. Despite several studies reporting the health benefits of OBB in treating ulcerative colitis (UC), its specific mechanism of action has yet to be fully elucidated.

Purpose

This investigation is designed to explore the potential protective efficacy of OBB and the latent mechanism using an in vitro model of UC-like inflammatory intestinal cells.

Methods

Caco-2 cells were pretreated with OBB and subsequently exposed to lipopolysaccharide (LPS). The transepithelial electrical resistance (TEER), paracellular permeability, and the distribution and expression of tight- and adherent junction proteins were determined to assess barrier integrity. The levels of proinflammatory cytokines, reactive oxygen species (ROS), Nrf2, and NF-κB signaling cascade were analyzed via ELISA, qRT-PCR, immunofluorescence, or Western blotting.

Results

OBB was found to mitigate the effects of LPS on Caco-2 cell monolayers, as evidenced by the improvement in TEER and the decrease in FITC-dextran flux. Moreover, OBB ameliorated the LPS-induced decrease in the distribution and expression of several tight junction markers, including ZO-1, occludin, and E-cadherin. In addition, OBB treatment effectively inhibited LPS-induced increases in ROS, apoptosis, and Keap1 and decreases in Nrf2 and HO-1. LPS-induced elevations in nuclear NF-κB p65 and p-IκBα were suppressed by OBB. In addition, ML385, an antagonist of Nrf2, abolished the protective role of OBB.

Conclusion

OBB has a pronounced beneficial effect on LPS-induced damage to enteral barrier function, and the regulation of the Nrf2/NF-κB pathway is an important mechanism responsible for the protection afforded by OBB.

Emerging targets in amyotrophic lateral sclerosis (ALS): The promise of ATP-binding cassette (ABC) transporter modulation

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative primarily affecting motor neurons, leading to disability and neuronal death, and ATP-Binding Cassette (ABC) transporter due to their role in drug efflux and modulation of various cellular pathways contributes to the pathogenesis of ALS. In this article, we extensively investigated various molecular and mechanistic pathways linking ALS transporter to the pathogenesis of ALS; this involves inflammatory pathways such as Mitogen-Activated Protein Kinase (MAPK), Phosphatidylinositol-3-Kinase/Protein Kinase B (PI3K/Akt), Toll-Like Receptor (TLR), Glycogen Synthase Kinase 3β (GSK-3β), Nuclear Factor Kappa-B (NF-κB), and Cyclooxygenase (COX). Oxidative pathways such as Astrocytes, Glutamate, Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), Sirtuin 1 (SIRT-1), Forkhead box protein O (FOXO), Extracellular signal-regulated kinase (ERK). Additionally, we delve into the role of autophagic pathways like TAR DNA-binding protein 43 (TDP-43), AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), and lastly, the apoptotic pathways. Furthermore, by understanding these intricate interactions, we aim to develop novel therapeutic strategies targeting ABC transporters, improving drug delivery, and ultimately offering a promising avenue for treating ALS.

The Antioxidant Ergothioneine Alleviates Cisplatin-Induced Hearing Loss Through the Nrf2 Pathway

Aims: Cisplatin (CDDP) is a commonly used chemotherapeutic agent for treating head and neck tumors. However, there is high incidence of ototoxicity in patients treated with CDDP, which may be caused by the excessive reactive oxygen species (ROS) generation in the inner ear. Many studies have demonstrated the strong antioxidant effects of ergothioneine (EGT). Therefore, we assumed that EGT could also attenuate cisplatin-induced hearing loss (CIHL) as well. However, the protective effect and mechanism of EGT on CIHL have not been elucidated as so far. In this study, we investigated whether EGT could treat CIHL and the mechanism. Results: In our study, we confirmed the protective effect of EGT on preventing CDDP-induced toxicity both in vitro and in vivo. The auditory brainstem response threshold shift in the EGT + CDDP treatment mice was 30 dB less than that in the CDDP treatment mice. EGT suppressed production of ROS and proapoptotic proteins both in tissue and cells. By silencing nuclear factor erythroid 2-related factor 2 (Nrf2), we confirmed that EGT protected against CIHL via the Nrf2 pathway. We also found that SLC22A4 (OCTN1), an important molecule involved in transporting EGT, was expressed in the cochlea. Innovation: Our results revealed the role of EGT in the prevention of CIHL by activating Nrf2/HO-1/NQO-1 pathway, and broadened a new perspective therapeutic target of EGT. Conclusion: EGT decreased ROS production and promoted the expression of antioxidative enzymes to maintain redox homeostasis in sensory hair cells. Overall, our results indicated that EGT may serve as a novel treatment drug to attenuate CIHL. Antioxid. Redox Signal. 42, 97-114.

Melatonin alleviates oral epithelial cell inflammation via Keap1/Nrf2 signaling

BACKGROUND

Oral mucosal diseases manifest primarily as inflammatory conditions. These diseases affect approximately half a billion people worldwide.

OBJECTIVE

Novel and effective strategies for treating inflammatory diseases of the oral mucosa have great potential for improving patient outcomes, and warrant study.

METHODS

The impact of melatonin on inflammation was investigated using RAW264.7 macrophages and HOEC and HSC-3 oral epithelial cells.

RESULTS

Melatonin decreased macrophage-induced inflammation by acting through the melatonin receptor MTNR1A. Additionally, melatonin mitigated macrophage-induced inflammation in oral epithelial cells. Importantly, the results demonstrated that the effects of melatonin on oral epithelial inflammation were mediated through the KEAP1/Nrf2 signaling pathway.

CONCLUSION

These findings will contribute to the development of innovative therapies for inflammatory conditions affecting the oral epithelium.

BAK ameliorated cerebral infarction/ischemia-reperfusion injury by activating AMPK/Nrf2 to inhibit TXNIP/NLRP3/caspase-1 axis

BACKGROUND

Cerebral ischemia/reperfusion (I/R) injury is a serious vascular disease with extremely high mortality and disability rate. Bakuchiol (BAK) was found in leaves and seeds of Psoralea corylifolia Linn and has been shown to decrease inflammation and reduce oxidative stress, while the mechanism of BAK in ameliorating cerebral I/R injury remains unclear.

METHODS

Middle cerebral artery occlusion reperfusion (MACO/R) was used to establish mouse model. The protective effect of BAK in MCAO/R mices was detected by performing neurological deficit testing, TTC staining, and H&E staining. Oxygen/glucose deprivation and reperfusion (OGD/R) was used to stimulate SH-SY5Y cells in vitro. Protein expression was detected by western blotting, gene expression was detected by quantitative real-time polymerase chain reaction and apoptosis was detected by immunofluorescence.

RESULTS

Our study indicated that BAK protected ischemia-reperfusion injury in MACO/R mice, and upregulated superoxide dismutase (SOD) and the catalase (CAT) enzyme activity. BAK also inhibited the expression of TNF-α, IL-1β, IL-6, and IL-18 and suppressed apoptosis and pyroptosis both in MACO/R mice and in OGD/R SH-SY5Y cells. Further results showed that BAK could suppress TXNIP, ASC, NLRP3, and caspase-1 mRNA levels to reverse assembly of inflammasome. And BAK could also upregulate the expression of phosphorylated AMP-activated protein kinase (AMPK) and nuclear factor erythroid 2-related factor (Nrf2). In addition, Nrf2 inhibitor ML385 reversed the BAK induced reduction of TXNIP, ASC, NLRP3, and the AMPK inhibitor also abolished BAK' the effect on the regulation of Nrf2, TXNIP, ASC, NLRP3, caspase-1, and pro-inflammatory cytokines. In conclusion, BAK, found in leaves and seeds of Psoralea corylifolia Linn, could ameliorated cerebral I/R injury through activating AMPK/Nrf2 to inhibit NLRP3 inflammasome, which might present new therapeutic strategy for cerebral I/R injury.

Nrf2 and Ferroptosis: Exploring Translational Avenues for Therapeutic Approaches to Neurological Diseases

Nrf2, a crucial protein involved in defense mechanisms, particularly oxidative stress, plays a significant role in neurological diseases (NDs) by reducing oxidative stress and inflammation. NDs, including Alzheimer's, Parkinson's, Huntington's, amyotrophic lateral sclerosis, stroke, epilepsy, schizophrenia, depression, and autism, exhibit ferroptosis, iron-dependent regulated cell death resulting from lipid and iron-dependent reactive oxygen species (ROS) accumulation. Nrf2 has been shown to play a critical role in regulating ferroptosis in NDs. Age-related decline in Nrf2 expression and its target genes (HO-1, Nqo-1, and Trx) coincides with increased iron-mediated cell death, leading to ND onset. The modulation of iron-dependent cell death and ferroptosis by Nrf2 through various cellular and molecular mechanisms offers a potential therapeutic pathway for understanding the pathological processes underlying these NDs. This review emphasizes the mechanistic role of Nrf2 and ferroptosis in multiple NDs, providing valuable insights for future research and therapeutic approaches.

Natural Products in the Prevention of Degenerative Bone and Joint Diseases: Mechanisms Based on the Regulation of Ferroptosis

Degenerative bone and joint diseases (DBJDs), characterized by osteoporosis, osteoarthritis, and chronic inflammation of surrounding soft tissues, are systemic conditions primarily affecting the skeletal system. Ferroptosis, a programmed cell death pathway distinct from apoptosis, autophagy, and necroptosis. Accumulating evidence suggests that ferroptosis is intricately linked to the pathogenesis of DBJDs, and targeting its regulation could be beneficial in managing these conditions. Natural products, known for their anti-inflammatory and antioxidant properties, have shown unique advantages in preventing DBJDs, potentially through modulating ferroptosis. This article provides an overview of the latest research on ferroptosis, with a focus on its role in the pathogenesis of DBJDs and the therapeutic potential of natural products targeting this cell death pathway, offering novel insights for the prevention and treatment of DBJDs.

Arsenic-induced transition of thymic inflammation-to-fibrosis involves Stat3-Twist1 interaction: Melatonin to the rescue

Groundwater arsenic is a notorious toxicant and exposure to environmentally relevant concentrations persists as a healthcare burden across the world. Arsenic has been reported to jeopardize the normal functioning of the immune system, but there are still gaps in the understanding of thymic T cell biology. Immunotoxic influence of arsenic in thymic integrity demands a potent restorative molecule. The objectives of this study were to examine key signaling cross-talks associated with arsenic-induced immune alterations in the thymus and propose melatonin as a potential candidate against immunological complications arising from arsenic exposure. Swiss albino mice were exposed to sodium arsenite (0.05 mg/L; in drinking water) and melatonin (IP:10 mg/kg BW) for 28 days. Melatonin successfully protected thymus from arsenic-mediated tissue degeneration and maintained immune homeostasis including T cell maturation and proliferation by mitigating oxidative stress through Nrf2 upregulation. Additionally, melatonin exerted ameliorative effect against arsenic-induced apoptosis and inflammation by inhibiting p53-mediated mitochondrial cell death pathway and NF-κB-p65/STAT3-mediated proinflammatory pathway, respectively. For the first time, we showed that arsenic-induced profibrotic changes were inhibited by melatonin through targeting of inflammation-associated EMT. Our findings clearly demonstrate that melatonin can be a viable and promising candidate in combating arsenic-induced immune toxicity with no collateral damage, making it an important research target.

Comprehensive Review of Biological Functions and Therapeutic Potential of Perilla Seed Meal Proteins and Peptides

This comprehensive review explores the biological functions of Perilla frutescens seed proteins and peptides, highlighting their significant potential for health and therapeutic applications. This review delves into the mechanisms through which perilla peptides combat oxidative stress and protect cells from oxidative damage, encompassing free radical scavenging, metal chelating, in vivo antioxidant, and cytoprotective activities. Perilla peptides exhibit robust anti-aging properties by activating the Nrf2 pathway, enhancing cellular antioxidant capacity, and supporting skin health through the promotion of keratinocyte growth, maintenance of collagen integrity, and reduction in senescent cells. Additionally, they demonstrate antidiabetic activity by inhibiting α-amylase and α-glucosidase. The cardioprotective effects of perilla peptides are underscored by ACE-inhibitory activities and combat oxidative stress through enhanced antioxidant defenses. Further, perilla peptides contribute to improved gut health by enhancing beneficial gut flora and reinforcing intestinal barriers. In liver, kidney, and testicular health, they reduce oxidative stress and apoptotic damage while normalizing electrolyte levels and protecting against cyclophosphamide-induced reproductive and endocrine disruptions by restoring hormone synthesis. Promising anticancer potential is also demonstrated by perilla peptides through the inhibition of key cancer cell lines, alongside their anti-inflammatory and immunomodulating activities. Their anti-fatigue effects enhance exercise performance and muscle function, while perilla seed peptide nanoparticles show potential for targeted drug delivery. The diverse applications of perilla peptides support their potential as functional food additives and therapeutic agents.

Chronic intermittent hypobaric hypoxia alleviates early-stage posttraumatic osteoarthritis via NF-κB/Nrf2 pathway in mice

BACKGROUND

Posttraumatic osteoarthritis (PTOA) is directly associated with early acute articular cartilage injury. Inhibition of cartilage destruction immediately following joint damage can effectively slow or prevent PTOA progression. Therefore, we sought to determine intervention targets and therapeutic strategies in the acute stage of cartilage injury. The benefits of chronic intermittent hypobaric hypoxia (CIHH) extend to various body tissues, but its impact on acute cartilage injury remains unclear. We selected PTOA initiation as the therapeutic window and administered CIHH treatment immediately following cartilage injury initiation to investigate its protective effect on cartilage and molecular mechanism changing with time-varying.

METHODS

The non-invasive PTOA mouse model was established by applying a single rapid specific impact force to the right knee's tibial plateau, initiating load-induced PTOA development, closely resembling the pathological changes in human diseases. Following loading, we inhibited cartilage destruction by treating mice immediately in a hypobaric chamber with a hypobaric hypoxia mimic at 5000 m altitude. Cohorts of mice subjected to distinct experimental conditions were monitored for 3, 7, 14 or 28 days. Safranin O-Fast Green staining, Immunohistochemistry, immunofluorescence, ELISA, and western blotting were performed to evaluate the therapeutic effects of CIHH on cartilage in vivo. The nuclear translocation of NF-κB p65 and Nrf2 were detected by immunofluorescence.

RESULTS

The results showed that inhibiting cartilage destruction using CIHH immediately following acute articular cartilage injury initiation delayed the progression of PTOA, decreased the Mankin score and suppressed the expression of proinflammatory factors, including iNOS, NO, TNF-α, and IL-1β. Meanwhile, immediate CIHH treatment reduced levels of the catabolic enzymes ADAMTS5 and MMP13 in the cartilage matrix, reversed degradation of Collagen II and COMP, and inhibited oxidative stress by decreasing ROS levels. Moreover, CIHH suppressed NF-κB signaling by activating the Nrf2 in vivo studies.

CONCLUSION

Our study demonstrated that immediate CIHH treatment following cartilage injury initiation can attenuate load-induced cartilage damage by activating Nrf2/HO-1 and inhibiting the NF-κB p65 signalling pathways to counteract oxidative stress and inflammatory reactions, enhance the metabolic balance of the cartilage matrix and delay cartilage degeneration. This treatment may represent a potential therapeutic strategy for limiting PTOA progression.

Nrf2/NRF1 signaling activation and crosstalk amplify mitochondrial biogenesis in the treatment of triptolide-induced cardiotoxicity using calycosin

Nuclear factor erythroid 2-related factor 2 (Nrf2) regulates both oxidative stress and mitochondrial biogenesis. Our previous study reported the cardioprotection of calycosin against triptolide toxicity through promoting mitochondrial biogenesis by activating nuclear respiratory factor 1 (NRF1), a coregulatory effect contributed by Nrf2 was not fully elucidated. This work aimed at investigating the involvement of Nrf2 in mitochondrial protection and elucidating Nrf2/NRF1 signaling crosstalk on amplifying the detoxification of calycosin. Results indicated that calycosin inhibited cardiomyocytes apoptosis and F-actin depolymerization following triptolide exposure. Cardiac contraction was improved by calycosin through increasing both fractional shortening (FS%) and ejection fraction (EF%). This enhanced contractile capacity of heart was benefited from mitochondrial protection reflected by ultrastructure improvement, augment in mitochondrial mass and ATP production. NRF1 overexpression in cardiomyocytes increased mitochondrial mass and DNA copy number, whereas NRF1 knockdown mitigated calycosin-mediated enhancement in mitochondrial mass. For nuclear Nrf2, it was upregulated by calycosin in a way of disrupting Nrf2-Keap1 (Kelch-like ECH associated protein 1) interaction, followed by inhibiting ubiquitination and degradation. The involvement of Nrf2 in mitochondrial protection was validated by the results that both Nrf2 knockdown and Nrf2 inhibitor blocked the calycosin effects on mitochondrial biogenesis and respiration. In the case of calycosin treatment, its effect on NRF1 and Nrf2 upregulations were respectively blocked by PGCα/Nrf2 and NRF1 knockdown, indicative of the mutual regulation between Nrf2 and NRF1. Accordingly, calycosin activated Nrf2/NRF1 and the signaling crosstalk, leading to mitochondrial biogenesis amplification, which would become a novel mechanism of calycosin against triptolide-induced cardiotoxicity.

The Keap1-Nrf2/ARE signaling pathway regulates redox balance and apoptosis in the small yellow croaker (Larimichthys polyactis) under hypoxic stress

Hypoxic stress can result in redox imbalance and apoptosis in teleostean fishes; however, the precise molecular mechanisms underlying this process, including its regulation by the key signaling pathway Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2 related factor (Nrf2)/antioxidant response element (ARE), remain elusive. Therefore, in this study, we chose the Keap1-Nrf2/ARE signaling pathway as the entry point and a combination of in vivo (target organ liver) and in vitro (small yellow croaker fry [SYCF] cell line) experiments to investigate the molecular mechanism by which Larimichthys polyactis (L. polyactis) adapts to hypoxic stress by regulating redox balance and apoptosis. As our previous study found that hypoxic stress could lead to redox imbalance and apoptosis in L. polyactis. First, we observed significant alterations in the expression of key genes Lpkeap1, Lpnrf2, Lpho-1, and Lpnqo1 within the Keap1-Nrf2/ARE signaling pathway in both liver tissue and SYCF cells of L. polyactis under hypoxic stress, indicating activation of this pathway in response to hypoxia. Subsequently, we elucidated the mechanism by which hypoxia activates this pathway, that is, hypoxia weakened the interaction between LpNrf2 and LpKeap1, promoting the nuclear translocation of LpNrf2 and enhancing its binding activity to ARE, thereby activating the transcription of target genes. Furthermore, we found that significant changes occurred in the redox balance and apoptosis-related indicators after LpNrf2 knockdown and exposure to hypoxic stress for 24 h in SYCF cells, indicating that this pathway can regulate redox balance and apoptosis regulation under hypoxic stress in L. polyactis. Additionally, we used DNA affinity purification sequencing (DAP-seq) to identify the ARE sequence (ATGATTTAGC) that bound to LpNrf2 and its target genes. Finally, we conducted a combined analysis of DAP-seq and RNA-seq to identify six key target genes involved in the process: haeme oxygenase-1 (Ho-1), B-cell lymphoma-2 (Bcl2), pituitary homeobox 2 isoform X1 (Pitx2), aquaporin-4 isoform X1 (Aqp4), stress-induced phosphoprotein 1-like isoform X1 (Stip1), and guanine nucleotide-binding protein G (i) subunit alpha-2-like (Gnai2). In summary, hypoxic stress induced by weakening LpNrf2 and LpKeap1 interaction promoted LpNrf2 nuclear entry and enhanced its binding activity to ARE, thereby activating the transcription of multiple target genes to regulate redox balance and apoptosis. The research results not only help deepen our understanding of the adaptive mechanisms of L. polyactis and even marine fish to hypoxic stress and its survival strategies but also provide new ideas and potential targets for breeding new hypoxia-tolerant strains.

Demyelination in cuprizone mice is ameliorated by calycosin mediated through astrocyte Nrf2 signaling pathway

Oxidative stress plays a pivotal role in multiple sclerosis (MS), triggering demyelination predominantly through excessive peroxide production and the depletion of antioxidants. The accumulation of oxidative damage can be caused by dysregulation of astrocytes, which are the brain's main regulators of oxidative homeostasis. Calycosin, an essential bioactive component extracted from Astragalus, is recognized for its neuroprotective properties. Although recent research has highlighted calycosin's neuroprotective capabilities, its role in demyelinating conditions like MS remains unclear. In this work, we examined the possible molecular mechanism of calycosin's neuroprotective effect on cuprizone (CPZ)-induced demylination in mice. According to our research, calycosin successfully reduced demyelination and behavioral dysfuction in CPZ mice. Calycosin also decreased the production of oxidative stress and enhanced the expression of antioxidants in CPZ mice and in astrocytes induced by hydrogen peroxide (H2O2). Furthermore, both in vivo and in vitro experiments demonstrated that calycosin promoted the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) along with the upregulation of heme oxygenase 1 (HO-1), NAD(P)H quinone dehydrogenase 1 (NQO1), and superoxide dismutase (SOD). Importantly, the application of all-trans retinoic acid (ATRA), a specific inhibitor of Nrf2, effectively reversed the myelin-protective and antioxidant effects conferred by calycosin. This study suggested that calycosin might exert neuroprotection by inhibiting oxidative stress and reducing demyelination via the activation of astrocyte Nrf2 signaling. These findings indicated that calycosin might be a potential candidate for treating MS.

Nrf2-Independent Anti-Inflammatory Effects of Dimethyl Fumarate: Challenges and Prospects in Developing Electrophilic Nrf2 Activators for Neurodegenerative Diseases

The NF-E2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway is a potential therapeutic target for central nervous system diseases. This review emphasizes the role of oxidative stress and neuroinflammation in neurodegenerative diseases, highlighting the therapeutic potential of Nrf2 activators such as dimethyl fumarate (DMF). DMF, initially administered for treating psoriasis, has demonstrated efficacy in multiple sclerosis and is metabolized to monomethyl fumarate, which may exert significant therapeutic effects. DMF activates the Nrf2-ARE pathway, and recent studies have indicated that its anti-inflammatory effects occur through Nrf2-independent mechanisms. Electrophilic Nrf2 activators, such as DMF, covalently bind to cysteine residues in proteins and modulate their function. We discuss the implications of cysteine residue modifications by DMF, which may cause both therapeutic benefits and potential off-target effects. Furthermore, we propose a chemical proteomics-based drug discovery approach to achieve desired therapeutic effects by selectively covalently modifying cysteines in target proteins. These findings advocate for a broader understanding of the Nrf2-independent mechanisms of electrophilic Nrf2 activators, thereby improving drug discovery strategies that target neurodegenerative diseases while minimizing toxicity.

Acrolein scavengers and detoxification: From high-throughput screening of flavonoids to mechanistic study of epigallocatechin gallate

Acrolein (ACR) is a widespread, highly toxic substance that poses significant health risks. Flavonoids have been recognized as effective ACR scavengers, offering a possible way to reduce these risks. However, the lack of specific high-throughput screening methods has limited the identification of ACR scavengers, and their actual detoxifying capacity on ACR remains unknown. To address this, we developed a high-throughput screening platform to assess the ACR scavenging capacity of 322 flavonoids. Our results showed that 80.7 % of the flavonoids could scavenge ACR, but only 34.4 % exhibited detoxifying effects in an ACR-injured QSG7701 cell model. Some flavonoids even increased toxicity. Structure-activity relationship (SAR) analysis indicated that galloyl and pyrogallol units enhance scavenging but worsen ACR-induced cytotoxicity. Further investigation revealed that epigallocatechin gallate (EGCG) could exacerbate ACR-induced redox disorder, leading to cell apoptosis. Our findings provide crucial data on the scavenging and detoxifying capacities of 322 flavonoids, highlighting that ACR scavengers might not mitigate ACR-induced toxicity and could pose additional safety risks.

Gypenoside A-loaded mPEG-PLGA nanoparticles ameliorate high-glucose-induced retinal microvasculopathy by inhibiting ferroptosis

Diabetic retinopathy (DR) is one of the chronic microvascular complications of type 2 diabetes mellitus (T2DM), which will cause retinal detachment and blindness without ideal therapies. Gypenoside A (GPA) are the main bioactive compound from Gynostemma pentaphyllum, and have various pharmacological effects. However, it suffered from poor bioavailability and potential cardiotoxicity in the clinical application. To overcome those limitations, in this study, nearly spherical nanoparticles (GPA-NP) with a mean particle size of 140.6 ± 22.4 nm were prepared by encapsulating GPA into mPEG-PLGA. This encapsulation efficiency was 84.4 ± 6.9 %, and the drug load was 4.02 %±0.35 %. The results showed that GPA-NP displayed more prolonged GPA release and higher bioavailability in vitro than GPA. GPA-NP obviously reduced the levels of oxidative stress markers and inflammatory cytokines in both retinal tissues of DR mice and high glucose-exposed HRMEC better than GPA alone. Mechanismly, GPA blocked the Nrf2-Keap1 interaction by binding with Kelch domain of Keap1 via alkyl and hydrogen bonds. Therefore, GPA-NP exerted more potent protectivity effects against high glucose-induced retinal microvascular endothelial ferroptosis in vitro and in vivo by activating Nrf2/HO-1/GPX4 pathway. It could be a promising therapeutic agent for preventing DR.

Cytoprotective Effects and Intranuclear Localization of Sulfur-Containing Derivative of Buckminsterfullerene

BACKGROUND

There is a growing interest in exploring the biological characteristics of nanoparticles and exploring their potential applications. However, there is still a lack of research into the potential genotoxicity of fullerene derivatives and their impact on gene expression in human cells. In this study, we investigated the effects of a water-soluble fullerene derivative, C60[C6H4SCH2COOK]5H (F1), on human embryonic lung fibroblasts (HELF).

METHODS

3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was used to study the cytotoxicity of F1; reactive oxygen species (ROS) level was determined with 2,7-DCFH-DA; gene expression level was evaluated by reverse transcription polymerase chain reaction (RT-PCR); protein expression level was determined by flow cytofluorometry; fluorescence microscopy was used for visualization; Mann-Whitney statistical U-test was used for data processing. The differences were considered significant at p < 0.01.

RESULTS

F1 at a concentration of 0.3 mg/mL causes a short-term (up to 1 hour) increase in the number of double-strand breaks and oxidative DNA damage in HELF. Within 1 to 24 hours, F1 penetrates through the cell and nuclear membrane of HELF and localizes in the nucleus. In this case, the response of cells to DNA damage is activated: the functional activity of DNA repair genes, antioxidant and anti-apoptotic genes is increased within 24 hours. Due to the processes of activation of cell division and inhibition of apoptosis, an increase in the population of HELF cells in the presence of the fullerene derivative F1 is observed. F1 has a stabilizing effect on cell nuclei under the action of 1 Gy radiation.

CONCLUSIONS

An increase in antioxidant protection, activation of repair genes, anti-apoptotic genes, progression of the cell cycle, and a decrease in the level of oxidative damage, and DNA breaks in cells indicates the cytoprotective properties of F1.

State-of-the-Art Nrf2 Inhibitors: Therapeutic Opportunities in Non-Cancer Diseases

Nuclear factor erythroid 2-related factor (Nrf2) is a cytoprotective transcription factor that induces the transcription of genes responsible for the cell's response to oxidative stress. While Nrf2 activation has led to the development of clinically relevant therapeutics, the oncogenic role of Nrf2 in the proliferation of cancer cells has underscored the complex nature of Nrf2 and the necessity for the development of Nrf2 inhibitors. Although the application of Nrf2 inhibitors appears limited as anticancer agents, recent studies have begun to pinpoint the impairment of autophagy in diseases as a cellular marker that shifts Nrf2 from a protective to a deleterious state. Therefore, the cytoplasmic accumulation of Nrf2 can lead to the accumulation of lipid hydroperoxides and, ultimately, to ferroptosis. However, some studies aimed at elucidating the role of Nrf2 in non-cancer diseases have yielded conflicting results, attributed to differences in approaches used to inhibit or activate Nrf2, as well as variations in in vitro and/or in vivo disease models. Overall, these results highlight the necessity for a deeper evaluation of Nrf2's role in diseases, especially chronic diseases. In this review, we discuss diseases where Nrf2 inhibition holds potential for beneficial therapeutic effects and summarize recently reported Nrf2 inhibitors exploiting medicinal chemistry approaches suitable for targeting transcription factors like Nrf2.

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

BACKGROUND

Reproductive 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.

RESULTS

A 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.

CONCLUSIONS

Lycopene 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).

Ebeiedinone and peimisine inhibit cigarette smoke extract-induced oxidative stress injury and apoptosis in BEAS-2B cells

Ebeiedinone and peimisine are the major active ingredients of Fritillariae Cirrhosae Bulbus. In this study, we looked at how these two forms of isosteroidal alkaloids protect human bronchial epithelial BEAS-2B cells from oxidative stress and apoptosis caused by cigarette smoke extract (CSE). First, the cytotoxicity was determined using the CCK8 assay, and an oxidative stress model was established. Then the antioxidative stress activity and mechanism were investigated by ELISA, flow cytometry, and Western blotting. By the CCK-8 assay, exposure to CSE (20%, 40%, and 100%) reduced the viability of BEAB-2S cells. The flow cytometry findings indicated that CSE-induced production of ROS (0.5% to maximum) and treatments with 10 μM ebeiedinone and 20 μM peimisine attenuated the production of ROS. The western blot assay results indicate that ebeiedinone and peimisine reduce CSE-induced oxidative stress, DNA damage, apoptosis, and autophagy dysregulation by inhibiting ROS, upregulating SOD and GSH/GSSG, and downregulating MDA, 4-HNE, and 8-OHdG through the NRF2/KEAP1 and JNK/MAPK-dependent pathways, thereby delaying the pathological progression of COPD caused by CS.Our data suggest that CSE causes oxidative stress, DNA damage, and apoptosis in BEAS-2B cells, as well as the progression of COPD. Ebeiedinone and peimisine fight CS-induced COPD by suppressing autophagy deregulation and apoptosis.

GLP-1 receptor agonist liraglutide alleviates kidney injury by regulating nuclear translocation of NRF2 in diabetic nephropathy

Diabetic nephropathy (DN) is a severe renal disorder that arises as a complication of diabetes. Liraglutide, an analogue of a glucagon-like peptide 1 (GLP-1) receptor agonist, has been shown to decrease diabetes-caused renal damage. Nevertheless, the complete understanding of the roles and mechanism remains unclear. In our study, diabetic rat models were created through a single intraperitoneal injection of streptozotocin (STZ). The level of fasting blood glucose, 24-h urine protein, serum creatinine (Scr) and blood urea nitrogen (BUN) were assessed. Periodic acid-Schiff (PAS) staining was applied to examine the pathological changes in renal tissues. Reactive oxygen species (ROS) formation was measured via dichloro-dihydro-fluorescein diacetate (DCFH-DA) probes. Western blot was conducted to examine the levels of oxidative stress-related and extracellular matrix (ECM)-associated proteins. The nuclear translocation of NRF2 was investigated through immunofluorescence and Western blot assays. We demonstrated that liraglutide attenuated DN-induced oxidative stress and ECM deposition in vitro and in vivo. Liraglutide exerted a reno-protective effect by promoting nuclear translocation of NRF2 in mesangial cells. ML385, an NRF2 inhibitor, counteracted the beneficial impact of liraglutide.

Pharmacotherapeutic potential of bilobetin to combat chromium induced hepatotoxicity via regulating TLR-4, Nrf-2/Keap-1, JAK1/STAT3 and NF-κB pathway: A pharmacokinetic and molecular dynamic approach

BACKGROUND

Chromium (Cr) is one of the top-notch noxious heavy metals that is documented to exert deleterious effects on various body organs including the liver. Bilobetin (BLB) is a natural flavonoid which exhibits a wide range of medicinal properties.

AIM

This trial was executed to investigate the pharmacotherapeutic potential of BLB to avert Cr instigated hepatotoxicity via modulating TLR4, JAK1/STAT3, Nrf-2/Keap-1 and NF-κB pathway.

RESEARCH LAYOUT

Our trial was executed on thirty-six male albino rats that were segregated into four equal groups including the control, Cr (10 mg/kg), Cr (10 mg/kg) + BLB (12 mg/kg) and BLB (12 mg/kg) alone treated group. Various biochemical parameters were assessed by using qRT-PCR, molecular docking, molecular dynamic simulation and histological approaches.

FINDINGS

Our results revealed that Cr administration significantly impaired the health of hepatic tissues by reducing the gene expression of Nrf-2 and its downregulating genes while promoting the levels of oxidative stress markers (ROS and MDA). Moreover, Cr administration upregulated the hepatic enzymes including ALT, GGT, AST, and ALP while concurrently decreasing the levels of total protein and albumin. Cr exposure also elevated the gene expression of pro-inflammatory cytokines including toll-like receptor 4 (TLR4), high mobility group box 1 (HMGB1) nuclear factor kappa B (NF-κB), Janus kinase 1 (JAK1), signal transducer and activator of transcription 3 (STAT3), tumor necrosis factor alpha (TNF-α), C-reactive proteins, interferon-gamma inducible protein-10 (IP-10), Interleukin beta-1(IL-1β), monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2). Hepatic apoptosis was observed to be elevated following the Cr intoxication. Nonetheless, BLB treatment remarkably alleviated the hepatic damages via regulating the biochemical as well as histological profile of liver. Our findings are further endorsed by molecular docking analysis that demonstrated that BLB exhibit strong binding affinity to Keap-1 and STAT3 thus supporting its efficient hepatoprotective potential.

CONCLUSION

BLB protected the hepatic tissues via regulating Cr induced impairments. These findings were confirmed by molecular docking and molecular dynamic simulation analysis.

Ivacaftor attenuates gentamicin-induced ototoxicity through the CFTR-Nrf2-HO1/NQO1 pathway

OBJECTIVES

Gentamicin is one of the most common ototoxic drugs that can lower patients' quality of life. Oxidative stress is a key factors inducing sensory hair cell death during gentamicin administration. So far, there are no effective drugs to prevent or treat gentamicin- induced hearing loss. A recent study found cystic fibrosis transmembrane conductance regulator (CFTR) as a new target to modulate cellular oxidative balance. The objective of this study was to estimate the effect of the CFTR activator ivacaftor on gentamicin-induced ototoxicity and determine its mechanism.

METHODS

The hair cell count was analyzed by Myosin 7a staining. Apoptosis was analyzed by TUNEL Apoptosis Kit. Cellular reactive oxygen species (ROS) level was detected by DCFH-DA probes. The Nrf2 related proteins expression levels were analyzed by western blot.

RESULTS

An in vitro cochlear explant model showed that gentamicin caused ROS accumulation in sensory hair cells and induced apoptosis, and this effect was alleviated by pretreatment with ivacaftor. Western blotting showed that ivacaftor administration markedly increased the protein expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO1), and NAD(P)H:quinone oxidoreductase 1 (NQO1). The protective effect of ivacaftor was abolished by the Nrf2 inhibitor ML385.

DISCUSSION

Our results indicate the protective role of the CFTR-Nrf2-HO1/NQO1 pathway in gentamicin-induced ototoxicity. Ivacaftor may be repositioned or repurposed towards aminoglycosides-induced hearing loss.

Urban aerosol particulate matter promotes cellular senescence through mitochondrial ROS-mediated Akt/Nrf2 downregulation in human retinal pigment epithelial cells

Urban aerosol particulate matter (UPM) is widespread in the environment, and its concentration continues to increase. Several recent studies have reported that UPM results in premature cellular senescence, but few studies have investigated the molecular basis of UPM-induced senescence in retinal pigment epithelial (RPE) cells. In this study, we primarily evaluated UPM-induced premature senescence and the protective function of nuclear factor erythroid 2-related factor 2 (Nrf2) in human RPE ARPE-19 cells. The findings indicated that UPM exposure substantially induced premature cellular senescence in ARPE-19 cells, as observed by increased β-galactosidase activity, expression levels of senescence-associated marker proteins, and senescence-associated phenotypes. Such UPM-induced senescence is associated with mitochondrial oxidative stress-mediated phosphatidylinositol 3'-kinase/Akt/Nrf2 downregulation. Sulforaphane-mediated Nrf2 activation Sulforaphane-mediated upregulation of phosphorylated Nrf2 suppressed the decrease in its target antioxidant gene, NAD(P)H quinone oxidoreductase 1, under UPM, which notably prevented ARPE-19 cells from UPM-induced cellular senescence. By contrast, Nrf2 knockdown exacerbated cellular senescence and promoted oxidative stress. Collectively, our results demonstrate the regulatory role of Nrf2 in UPM-induced senescence of RPE cells and suggest that Nrf2 is a potential molecular target.

Unveiling Smyd-2's Role in Cytoplasmic Nrf-2 Sequestration and Ferroptosis Induction in Hippocampal Neurons After Cerebral Ischemia/Reperfusion

SET and MYND Domain-Containing 2 (Smyd-2), a specific protein lysine methyltransferase (PKMT), influences both histones and non-histones. Its role in cerebral ischemia/reperfusion (CIR), particularly in ferroptosis-a regulated form of cell death driven by lipid peroxidation-remains poorly understood. This study identifies the expression of Smyd-2 in the brain and investigates its relationship with neuronal programmed cell death (PCD). We specifically investigated how Smyd-2 regulates ferroptosis in CIR through its interaction with the Nuclear Factor Erythroid-2-related Factor-2 (Nrf-2)/Kelch-like ECH-associated protein (Keap-1) pathway. Smyd-2 knockout protects HT-22 cells from Erastin-induced ferroptosis but not TNF-α + Smac-mimetic-induced apoptosis/necroptosis. This neuroprotective effect of Smyd-2 knockout in HT-22 cells after Oxygen-Glucose Deprivation/Reperfusion (OGD/R) was reversed by Erastin. Smyd-2 knockout in HT-22 cells shows neuroprotection primarily via the Nuclear Factor Erythroid-2-related Factor-2 (Nrf-2)/Kelch-like ECH-associated protein (Keap-1) pathway, despite the concurrent upregulation of Smyd-2 and Nrf-2 observed in both the middle cerebral artery occlusion (MCAO) and OGD/R models. Interestingly, vivo experiments demonstrated that Smyd-2 knockout significantly reduced ferroptosis and lipid peroxidation in hippocampal neurons following CIR. Moreover, the Nrf-2 inhibitor ML-385 abolished the neuroprotective effects of Smyd-2 knockout, confirming the pivotal role of Nrf-2 in ferroptosis regulation. Cycloheximide (CHX) fails to reduce Nrf-2 expression in Smyd-2 knockout HT-22 cells. Smyd-2 knockout suppresses Nrf-2 lysine methylation, thereby promoting the Nrf-2/Keap-1 pathway without affecting the PKC-δ/Nrf-2 pathway. Conversely, Smyd-2 overexpression disrupts Nrf-2 nuclear translocation, exacerbating ferroptosis and oxidative stress, highlighting its dual regulatory role. This study underscores Smyd-2's potential for ischemic stroke treatment by disrupting the Smyd-2/Nrf-2-driven antioxidant capacity, leading to hippocampal neuronal ferroptosis. By clarifying the intricate interplay between ferroptosis and oxidative stress via the Nrf-2/Keap-1 pathway, our findings provide new insights into the molecular mechanisms of CIR and identify Smyd-2 as a promising therapeutic target.

Nrf2 pathways in neuroprotection: Alleviating mitochondrial dysfunction and cognitive impairment in aging

Mitochondrial dysfunction and cognitive impairment are widespread phenomena among the elderly, being crucial factors that contribute to neurodegenerative diseases. Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important regulator of cellular defense systems, including that against oxidative stress. As such, increased Nrf2 activity may serve as a strategy to avert mitochondrial dysfunction and cognitive decline. Scientific data on Nrf2-mediated neuroprotection was collected from PubMed, Google Scholar, and Science Direct, specifically addressing mitochondrial dysfunction and cognitive impairment in older people. Search terms included "Nrf2", "mitochondrial dysfunction," "cognitive impairment," and "neuroprotection." Studies focusing on in vitro and in vivo models and clinical investigations were included to review Nrf2's therapeutic potential comprehensively. The relative studies have demonstrated that increased Nrf2 activity could improve mitochondrial performance, decrease oxidative pressure, and mitigate cognitive impairment. To a large extent, this is achieved through the modulation of critical cellular signalling pathways such as the Keap1/Nrf2 pathway, mitochondrial biogenesis, and neuroinflammatory responses. The present review summarizes the recent progress in comprehending the molecular mechanisms regarding the neuroprotective benefits mediated by Nrf2 through its substantial role against mitochondrial dysfunction and cognitive impairment. This review also emphasizes Nrf2-target pathways and their contribution to cognitive function improvement and rescue from mitochondria-related abnormalities as treatment strategies for neurodegenerative diseases that often affect elderly individuals.

The therapeutic potential of Apigenin in amyotrophic lateral sclerosis through ALDH1A2/Nrf2/ARE signaling

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by motor neuron loss leading to muscle weakness and atrophy. Apigenin (APG), known for its antioxidant properties, holds potential as a therapeutic compound in ALS.

METHODS

We used the Tg(SOD1*G93A)1Gur/J transgenic mouse model of ALS to investigate the therapeutic effects of APG. Key measured included motor function via the ALSTDI score, molecular markers of oxidative stress (OS) and apoptosis in spinal cord tissues. Techniques used included pathological, Western blotting, flow cytometry, and qRT-PCR to assess the effect of ALDH1A2.

RESULTS

APG treatment attenuated weight loss and improved motor function scores in ALS mice compared to untreated ALS models. Molecular analyses revealed a significant upregulation of ALDH1A2 in APG-treated groups, along with a reduction in markers of OS and apoptosis. In vitro studies in NSC34 cells further confirmed the protective effects of APG against SOD1*G93A mutation-induced cytotoxicity. In addition, suppression of ALDH1A2 by shRNA exacerbated disease markers that were ameliorated by APG treatment.

CONCLUSIONS

Our results suggest that APG attenuates the progression of ALS pathology by regulating OS and apoptosis through ALDH1A2. These results support further investigation of APG as a potential therapeutic agent for the treatment of ALS.

New Emerging Therapeutic Strategies Based on Manipulation of the Redox Regulation Against Therapy Resistance in Cancer

Background: Resistance to standard therapeutic methods, including chemotherapy, immunotherapy, and targeted therapy, remains a critical challenge in effective cancer treatment. Redox homeostasis modification has emerged as a promising approach to address medication resistance. Objective: This review aims to explore the mechanisms of redox alterations and signaling pathways contributing to treatment resistance in cancer. Methods: In this study, a comprehensive review of the molecular mechanisms underlying drug resistance governed by redox signaling was conducted. Emphasis was placed on understanding how tumor cells manage increased reactive oxygen species (ROS) levels through upregulated antioxidant systems, enabling resistance across multiple therapeutic pathways. Results: Key mechanisms identified include alterations in drug efflux, target modifications, metabolic changes, enhanced DNA damage repair, stemness preservation, and tumor microenvironment remodeling. These pathways collectively facilitate tumor cells' adaptive response and resistance to various cancer treatments. Conclusion: Developing a detailed understanding of the interrelationships between these redox-regulated mechanisms and therapeutic resistance holds potential to improve treatment effectiveness, offering valuable insights for both fundamental and clinical cancer research. Antioxid. Redox Signal. 00, 000-000.

MicroRNA-mediated regulation of Ferroptosis: Implications for disease pathogenesis and therapeutic interventions

Ferroptosis, a form of iron-dependent regulated cell death, is characterized by the accumulation of lipid peroxides and distinctive morphological features. Moreover, the reduction of intracellular antioxidant enzyme expression or activity, specifically glutathione peroxidase 4 (GPX4) results in activation of the endogenous pathway of ferroptosis. In this review, we aimed to explore the intricate interplay between microRNAs (miRNAs) and ferroptosis, shedding light on its implications in various disease pathologies. This review delves into the role of miRNAs in modulating key regulators of ferroptosis, including genes involved in iron metabolism, lipid peroxidation, and antioxidant defenses. Furthermore, the potential of targeting miRNAs for therapeutic interventions in ferroptosis-related diseases, such as cancer, neurodegenerative disorders, and ischemia/reperfusion injury, is highlighted.

NRF2 in age-related musculoskeletal diseases: Role and treatment prospects

The NRF2 pathway is a metabolic- and redox-sensitive signaling axis in which the transcription factor controls the expression of a multitude of genes that enable cells to survive environmental stressors, such as oxidative stress, mainly by inducing the expression of cytoprotective genes. Basal NRF2 levels are maintained under normal physiological conditions, but when exposed to oxidative stress, cells activate the NRF2 pathway, which is crucial for supporting cell survival. Recently, the NRF2 pathway has been found to have novel functions in metabolic regulation and interplay with other signaling pathways, offering novel insights into the treatment of various diseases. Numerous studies have shown that targeting its pathway can effectively investigate the development and progression of age-related musculoskeletal diseases, such as sarcopenia, osteoporosis, osteoarthritis, and intervertebral disc degeneration. Appropriate regulation of the NRF2 pathway flux holds promise as a means to improve musculoskeletal function, thereby providing a new avenue for drug treatment of age-related musculoskeletal diseases in clinical settings. The review summarized an overview of the relationship between NRF2 and cellular processes such as oxidative stress, apoptosis, inflammation, mitochondrial dysfunction, ferroptosis, and autophagy, and explores the potential of targeted NRF2 regulation in the treatment of age-related musculoskeletal diseases.

Oxidised rice bran oil induced oxidative stress and apoptosis in IPEC-J2 cells via the Nrf2 signalling pathway

Rice bran oil is a type of rice oil made by leaching or pressing during rice processing and has a high absorption rate after consumption. When oxidative rancidity occurs, it may cause oxidative stress (OS) and affect intestinal function. Meanwhile, the toxic effects of oxidised rice bran oil have been less well studied in pigs. Therefore, the IPEC-J2 cells model was chosen to explore the regulatory mechanisms of oxidised rice bran oil on OS and apoptosis. Oxidised rice bran oil extract treatment (OR) significantly decreased the viability of IPEC-J2 cells. The results showed that OR significantly elevated apoptosis and reactive oxygen species levels and promoted the expression of pro-apoptotic gene Caspase-3 messenger RNA levels. The activation of Nrf2 signalling pathway by OR decreased the cellular antioxidant capacity. This was further evidenced by the expression of kelch-like ECH-associated protein 1, heme oxygenase 1, NADH: quinone oxidoreductase 1, superoxide dismutase 2 and heat shock 70 kDa protein genes and proteins were all downregulated. In conclusion, our results suggested that oxidised rice bran oil induced damage in IPEC-J2 cells through the Nrf2 signalling pathway.

MCL restrained ROS/AKT/ASAH1 pathway to therapy tamoxifen resistance breast cancer by stabilizing NRF2

Tamoxifen resistance is a common and difficult problem in the clinical treatment of breast cancer (BC). As a novel antitumor agent, Micheliolide (MCL) has shown a better therapeutic effect on tumours; however, little is known about MCL and its role in BC therapy. With tamoxifen stimulation, drug-resistant BC cells MCF7TAMR and T47DTAMR obtained a high oxidative status and Amidohydrolase 1 (ASAH1) was abnormally activated. The inhibition of ASAH1 rescued the sensitivity of resistant cells to tamoxifen. We found that MCL inhibited the expression of ASAH1 and cell proliferation, especially in MCF7TAMR and T47DTAMR cells. The high oxidative stress status of resistant cells stimulated the expression of ASAH1 by positively regulating AKT, which was restrained by MCL. MCL activated NRF2 by directly binding to KEAP1 and promoting the antioxidant level of tamoxifen-resistant (TAMR) cells. In addition, ACT001, the prodrug of MCL, significantly inhibited the tumour growth of TAMR cells in preclinical xenograft tumour models. In conclusion, ASAH1 mediates tamoxifen resistance in ER-positive BC cells. MCL could activate the cellular antioxidant system via NRF2/KEAP1 and inhibit ASAH1 expression through the ROS/AKT signalling pathway, thus suppressing cell proliferation. MCL could be used as a potential treatment for TAMR-BC.

Astragaloside IV reduces mutant Ataxin-3 levels and supports mitochondrial function in Spinocerebellar Ataxia Type 3

This study investigated the therapeutic effects of astragaloside IV (AST) on spinocerebellar ataxia type 3 (SCA3), also known as Machado-Joseph disease (MJD), a neurodegenerative disorder. Human neuroblastoma SK-N-SH cells expressing mutant ataxin-3 protein with 78 CAG repeats (MJD78) were employed as an in vitro model. Protein expression analysis demonstrated that AST treatment reduced mutant ataxin-3 protein expression and aggregation by enhancing the autophagic process in MJD78 cells. Elevated oxidative stress levels in MJD78 cells were significantly reduced following AST treatment, which also enhanced antioxidant capacity, as evidenced by flow cytometry and antioxidant enzyme activity assays. Furthermore, AST treatment ameliorated mitochondrial dysfunction in MJD78 cells, including improvements in mitochondrial membrane potential, respiration, and mitochondrial dynamics. In conclusion, AST administration increased antioxidant capacity, reduced both cellular and mitochondrial oxidative stress, and improved mitochondrial quality control processes through fusion, fission, and autophagy. These mechanisms collectively reduced intracellular mutant ataxin-3 protein aggregation, thereby achieving therapeutic efficacy in the SCA3 model.

Low miR-936-mediated upregulation of Pim-3 drives sorafenib resistance in liver cancer through ferroptosis inhibition by activating the ANKRD18A/Src/NRF2 pathway

Objective

Sorafenib, a multikinase inhibitor, is currently the standard treatment for advanced liver cancer. However, its application has become limited by the development of drug resistance. We intended to explore the mechanisms underlying the development of sorafenib resistance, therefore identifying an effective strategy to overcome sorafenib resistance remain challenges.

Methods

Here, the follow-up of liver cancer patients undergoing sorafenib therapy, as well as animal tumor challenge and treatment were performed. The sorafenib-resistant liver cancer cell lines Huh7/SOR and HepG2/SOR were also established. miRNA and mRNA microarray analyses, TargetScan prediction, dual luciferase reporter assay, RNA pull-down assay, co-mmunoprecipitation (Co-IP) and pull-down assays, a transcription factor-specific NRF2 assay, an iron detection assay, a lipid peroxidation quantification assay, a ROS measurement assay, and GSH/GSSG and GSH-px standard quantitative assays were used.

Results

We showed that upregulation of the provirus-integrating site for Moloney murine leukemia virus 3 (Pim-3) predicted poor response and unsatisfactory prognosis in sorafenib-treated liver cancer patients. Similarly, Pim-3 expression was positively associated with sorafenib resistance in liver cancer cells. Furthermore, microRNA-936 (miR-936) targeted the 3'-noncoding region (3'-UTR) of Pim-3 but exhibited lower expression in sorafenib-resistant liver cancer cells than in their parental cells. The high expression of Pim-3 mediated by miR-936 insufficiency activated the ANKRD18A/Src/NRF2 pathway which rearranged the expression of the indicated markers involved in iron distribution and lipid peroxidation homeostasis. MiR-936 overexpression and GV102-Pim-3-shRNA significantly attenuated the activity of the ANKRD18A/Src/NRF2 pathway to decrease the expression of Ankyrin repeat domain-containing protein 18A (ANKRD18A), Src, and Nuclear factor (erythroid-derived 2)-like 2 (NRF2), especially decreasing NRF2 nuclear retention and transcriptional activity. The transcriptional activity of NRF2 prompted cell ferroptosis because the transfection of miR-936 mimics, GV102-Pim-3-shRNA and GV102-NRF2-shRNA plasmid increased the expression of transferrin receptor 1 (TFR1) and divalent metal transporter 1 (DMT1) but decreased the expression of solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), quinone oxidoreductase 1 (NQO1), and heme oxygenase-1 (HO-1), thus facilitating the accumulation of intracellular Fe2+, lipid peroxides, and reactive oxygen species (ROS) but reducing the glutathione (GSH) level. Moreover, the elevated expression of Pim-3, resulting from the absence of miR-936 enhances sorafenib resistance in liver cancer by inhibiting cell ferroptosis.

Conclusion

Pim-3 can be regarded as a target in the treatment of sorafenib-resistant liver cancer.

Modular Nanotransporters Deliver Anti-Keap1 Monobody into Mouse Hepatocytes, Thereby Inhibiting Production of Reactive Oxygen Species

Background/Objectives: The study of oxidative stress in cells and ways to prevent it attract increasing attention. Antioxidant defense of cells can be activated by releasing the transcription factor Nrf2 from a complex with Keap1, its inhibitor protein. The aim of the work was to study the effect of the modular nanotransporter (MNT) carrying an R1 anti-Keap1 monobody (MNTR1) on cell homeostasis. Methods: The murine hepatocyte AML12 cells were used for the study. The interaction of fluorescently labeled MNTR1 with Keap1 fused to hrGFP was studied using the Fluorescence-Lifetime Imaging Microscopy-Förster Resonance Energy Transfer (FLIM-FRET) technique on living AML12 cells transfected with the Keap1-hrGFP gene. The release of Nrf2 from the complex with Keap1 and its levels in the cytoplasm and nuclei of the AML12 cells were examined using a cellular thermal shift assay (CETSA) and confocal laser scanning microscopy, respectively. The effect of MNT on the formation of reactive oxygen species was studied by flow cytometry using 6-carboxy-2',7'-dichlorodihydrofluorescein diacetate. Results: MNTR1 is able to interact with Keap1 in the cytoplasm, leading to the release of Nrf2 from the complex with Keap1 and a rapid rise in Nrf2 levels both in the cytoplasm and nuclei, ultimately causing protection of cells from the action of hydrogen peroxide. The possibility of cleavage of the monobody in endosomes leads to an increase in the observed effects. Conclusions: These findings open up a new approach to specifically modulating the interaction of intracellular proteins, as demonstrated by the example of the Keap1-Nrf2 system.

Aged gut microbiota promotes arrhythmia susceptibility via oxidative stress

Arrhythmias and sudden cardiac death (SCD) impose a significant burden. Their prevalence rises with age and is linked to gut dysbiosis. Our study aimed to determine whether aged gut microbiota affects arrhythmogenesis. Here, we demonstrated that arrhythmia susceptibility in aged mice could be transmitted to young mice using fecal microbiota transplantation (FMT). Mechanistically, increased intestinal reactive oxygen species (ROS) in aged mice reduced ion channel protein expression and promoted arrhythmias. Gut microbiota depletion by an antibiotic cocktail reduced ROS and arrhythmia in aged mice. Interestingly, oxidative stress in heart induced by hydrogen peroxide (H2O2) increased arrhythmia. Moreover, aged gut microbiota could induce oxidative stress in young mice colon by gut microbiota metabolites transplantation. Vitexin could reduce aging and arrhythmia through OLA1-Nrf2 signaling pathway. Overall, our study demonstrated that the gut microbiota of aged mice reduced cardiac ion channel protein expression through systemic oxidative stress, thereby increased the risk of arrhythmias.