Transcription factor Nrf2 coordinately regulates a group of oxidative stress-inducible genes in macrophages

Synergistic Neuroprotective Effects of Ergothioneine and Lactoferrin in APP/PS1 Transgenic Mice and Mouse N2a Cells

Ergothioneine and lactoferrin show antioxidant and neuroprotective effects, but their interactive effects and underlying mechanisms on Alzheimer's disease are unclear. This study aims to investigate the synergistic neuroprotective effect for a combination of ergothioneine and lactoferrin and the molecular mechanisms in APP/PS1 transgenic mice and neuroblast N2a cells. In transgenic mice, the combination of ergothioneine and lactoferrin improved cognitive function and alleviated typical Alzheimer's disease's pathological characteristics of Aβ aggregation and tau phosphorylation. In N2a cells, compared with ergothioneine or lactoferrin alone, their combination synergistically increased cell viability by approximately 15% and decreased apoptosis by 5% in flow cytometry. The combination of ergothioneine and lactoferrin showed a more enhanced antioxidant efficacy through Keap1/Nrf2-mediated mechanisms in comparison to ergothioneine or lactoferrin alone. In summary, the combination of ergothioneine and lactoferrin synergistically enhances neuroprotection in APP/PS1 transgenic mice and N2a cells, providing a foundation for the development of functional foods for the prevention and control of Alzheimer's disease.

Enhancing immunotherapy with tumour-responsive nanomaterials

The targeted delivery of immunotherapies to tumours using tumour-responsive nanomaterials is a promising area of cancer research with the potential to address the limitations of systemic administration such as on-target off-tumour toxicities and a lack of activity owing to the immunosuppressive tumour microenvironment (TME). Attempts to address these challenges include the design and functionalization of nanomaterials capable of releasing their cargoes in response to specific TME characteristics, thus facilitating the targeted delivery of immune-checkpoint inhibitors, cytokines, mRNAs, vaccines and, potentially, chimaeric antigen receptors as well as of agents that modulate the extracellular matrix and induce immunogenic cell death. In this Review, we describe these various research efforts in the context of the dynamic properties of the TME, such as pH, reductive conditions, reactive oxygen species, hypoxia, specific enzymes, high levels of ATP and locoregional aspects, which can be leveraged to enhance the specificity and efficacy of nanomaterial-based immunotherapies. Highlighting preclinical successes and ongoing clinical trials, we evaluate the current landscape and potential of these innovative approaches. We also consider future research directions as well as the most important barriers to successful clinical translation, emphasizing the transformative potential of tumour-responsive nanomaterials in overcoming the barriers that limit the activity of traditional immunotherapies, thus improving patient outcomes.

Extracts from petal of the Crocus sativus (saffron) possesses detoxification effects on acetaminophen induced liver injury by inhibiting hepatocyte apoptosis via regulating Nrf2/HO-1 signaling

The purpose of this study was to investigate the detoxification effect of extracts from the petal of Crocus sativus L. (PCSE) on acetaminophen (APAP) induced liver injury in mice and its related mechanisms. LC-MS/MS analysis was used to identify the main components in PCSE, and an APAP-induced acute liver injury model in mice was constructed to evaluate the detoxification effect of PCSE. Liver tissue H&E staining, liver function indexes including ALT and AST, pro-inflammatory cytokine including TNF-α and IL-6, as well as hepatic tissue oxidative stress levels were examined. In addition, in vitro APAP induced cell was also prepared, apoptosis levels were detected by AO/EB staining, ROS fluorescence intensity was analyzed as well as the expression levels of apoptosis-related proteins and Nrf2/HO-1 pathway-related proteins were detected by western blot, to investigate the mechanism of PCSE's action in ameliorating liver injury. The results showed that PCSE can improve the survival rate of APAP induced mice, decrease ALT, AST, TNF-α and IL-6 levels, and ameliorate the liver injury induced by APAP. Furthermore, the mechanism research suggested PCSE attenuated oxidative stress and apoptosis in APAP-induced liver cells, as well as activated the Nrf2/HO-1 signaling. In summary, PCSE possesses potential detoxification effects on APAP induced liver injury by inhibiting hepatocyte apoptosis via regulating Nrf2/HO-1 signaling, which provides more possibilities for the drug selection for the treatment of liver injury in clinical practice.

Natural flavonoids from herbs and nutraceuticals as ferroptosis inhibitors in central nervous system diseases: current preclinical evidence and future perspectives

Flavonoids are a class of important polyphenolic compounds, renowned for their antioxidant properties. However, recent studies have uncovered an additional function of these natural flavonoids: their ability to inhibit ferroptosis. Ferroptosis is a key mechanism driving cell death in central nervous system (CNS) diseases, including both acute injuries and chronic neurodegenerative disorders, characterized by iron overload-induced lipid peroxidation and dysfunction of the antioxidant defense system. This review discusses the therapeutic potential of natural flavonoids from herbs and nutraceuticals as ferroptosis inhibitors in CNS diseases, focusing on their molecular mechanisms, summarizing findings from preclinical animal models, and providing insights for clinical translation. We specifically highlight natural flavonoids such as Baicalin, Baicalein, Chrysin, Vitexin, Galangin, Quercetin, Isoquercetin, Eriodictyol, Proanthocyanidin, (-)-epigallocatechin-3-gallate, Dihydromyricetin, Soybean Isoflavones, Calycosin, Icariside II, and Safflower Yellow, which have shown promising results in animal models of acute CNS injuries, including ischemic stroke, cerebral ischemia-reperfusion injury, intracerebral hemorrhage, subarachnoid hemorrhage, traumatic brain injury, and spinal cord injury. Among these, Baicalin and its precursor Baicalein stand out due to extensive research and favorable outcomes in acute injury models. Mechanistically, these flavonoids not only regulate the Nrf2/ARE pathway and activate GPX4/GSH-related antioxidant pathways but also modulate iron metabolism proteins, thereby alleviating iron overload and inhibiting ferroptosis. While flavonoids show promise as ferroptosis inhibitors for CNS diseases, especially in acute injury settings, further studies are needed to evaluate their efficacy, safety, pharmacokinetics, and blood-brain barrier penetration for clinical application.

The antifibrotic effect of Vildagliptin and Diaminodiphenyl Sulfone in murine schistosomiasis mansoni

Schistosomiasis drastically affects human health, where S. mansoni-induced hepatic fibrosis remains a serious problem with no available drug yet. The current study aimed to evaluate the hepatoprotective effects of Vildagliptin (Vilda), Diaminodiphenyl Sulfone (DDS), and their combination (Vilda/DDS) against S. mansoni-induced hepatic fibrosis and elucidate their underlying molecular mechanisms. S.mansoni-infected mice were administered praziquantel (PZQ) for two consecutive days, or Vilda, DDS, and Vilda/DDS for 14 consecutive days. Schistosomiasis-induced hepatic fibrosis was assessed parasitologically, biochemically, and pathologically. Results revealed that Vilda, DDS, and Vida/DDS treatments significantly reduced worm count, oogram stages, ova count, and ameliorated the granulomatous inflammatory reactions and hepatotoxicity indices. Moreover, they enhanced hepatic Nrf2/HO-1 pathway with significant increasing SOD and reducing MDA levels. Furthermore, they significantly downregulated the hepatic TLR4/NF-κB and NLRP3 inflammasome pathways leading to a significant reduction in TNF-α and caspase-1 levels which is important in the activation of IL-1β and caspase-3. Notably, significant downregulation in hepatic TGF-β1, α-SMA, and MMP-9 expressions were also recorded. In conclusion, Vilda/DDS showed antioxidant, anti-inflammatory and antifibrotic activities in comparison to either Vilda or DDS alone against S. mansoni-induced hepatic fibrosis. Therefore, Vilda/DDS is a promising approach for managing S. mansoni infection, liver fibrosis, and associated disease morbidity.

Resveratrol alleviates testicular toxicity induced by anti-PD-1 through regulating the NRF2-SLC7A11-GPX4 pathway

Background

Fertility preservation is a critical concern for reproductive-age cancer survivors, as conventional cytotoxic therapies can cause irreversible damage to the reproductive system, potentially depriving them of the ability to have children in the future. Immune checkpoint inhibitors (ICIs), including anti-programmed cell death protein 1 (anti-PD-1), have become a standard therapeutic approach for various malignancies. However, the impact of ICIs on reproductive function and fertility is not well understood and remains a largely unexplored domain. Resveratrol (RSV), a plant-derived compound, has shown potential as an nuclear factor erythroid 2-related factor 2 (NRF2) agonist to counteract reproductive toxicity induced by various diseases, drugs, and environmental toxins.

Methods

Male C57BL6/J mice with B16 melanoma were assigned into four groups. RSV and ICI/RSV groups received RSV (40 mg/kg) orally every other day for one month, while controls received the vehicle. ICI and ICI/RSV groups were injected with anti-PD-1 antibody (10 mg/kg) weekly, and controls received IgG2b kappa antibody. Parameters like body and testicular weight, sperm concentration, and western blot for ferroptosis markers were measured. Furthermore, oxidative stress biomarkers, lipid oxidation factors, and gonadal hormone levels were quantified using commercial kits.

Results

Anti-PD-1 therapy caused male reproductive dysfunction, as evidenced by reduced sperm concentration, altered gonadal hormone levels, and disruption of blood-testis barrier (BTB) integrity. Furthermore, ferroptosis was a key mechanism in anti-PD-1-induced testicular dysfunction, characterized by disrupted iron homeostasis, elevated lipid peroxidation, and suppression of the system Xc-/glutathione peroxidase 4 (GPX4) axis. Additionally, anti-PD-1 therapy diminished antioxidant defenses by inhibiting the NRF2 pathway, thereby increasing the susceptibility to ferroptosis. Crucially, RSV treatment ameliorated anti-PD-1-induced reproductive dysfunction. This was achieved by reducing T cell infiltration, lowering interferon-gamma levels, activating the NRF2 pathway, and maintaining iron and lipid homeostasis.

Conclusions

Our study demonstrates that anti-PD-1 triggers oxidative stress and ferroptosis in the testis, causing male reproductive dysfunction. RSV may offer protection against testicular toxicity associated with anti-PD-1, particularly through its antioxidant and anti-ferroptosis properties.

The predominant role of p62/SQSTM1 over NBR1 in methylmercury-induced cytotoxicity and cellular defense

p62/SQSTM1 (p62) and neighbor of BRCA1 gene 1 (NBR1) are two important cargo receptors involved in selective autophagy. While p62 is known to safeguard cells against the toxic effects of the environmental toxicant methylmercury (MeHg), the specific functions of p62 and NBR1 in MeHg-exposed cells remain unclear. In this study, we aimed to elucidate the distinct roles of p62 and NBR1 in conferring protection against cytotoxicity induced by MeHg. We found that MeHg increased both the mRNA and protein levels of p62 while decreasing those of NBR1. Upon exposure to MeHg, p62-knockout (KO) cells exhibited an approximately 30 % reduction in cell viability compared to wild-type (WT) cells; however, no such reduction was observed in NBR1KO cells. Additionally, p62KO cells exhibited a 1.5-fold increase in intracellular mercury (Hg) concentration compared to the WT following MeHg exposure, whereas NBR1KO cells had Hg levels comparable to those of WT cells. Upon exposure to MeHg, Nrf2 signaling activation was significantly reduced in p62KO cells compared to that in WT cells, whereas NBR1KO cells displayed Nrf2 activation levels similar to those of WT cells. Overall, these results suggest that p62, rather than NBR1, plays a crucial role in mitigating MeHg-induced cytotoxicity by reducing intracellular Hg levels through the activation of the Nrf2 signaling pathway.

Hepatoprotective Effects of Cilnidipine in Cholestatic Liver Disease: Role of FXR and NRF2 Signalling

Background

Bile acid (BA) is a type of cholesterol derivative that has long been established for its crucial role in the breakdown and absorption of fat from food. Cholestasis occurs when the liver fails to transfer BAs to the intestines. Chronic cholestatic diseases can lead to liver cirrhosis.

Objective

Ursodeoxycholic acid (UDCA) treatment is ineffective for certain cholestatic diseases like benign recurrent intrahepatic cholestasis (BRIC), despite increasing the hydrophilic bile acid pool. Moreover, studies indicate that UDCA and other bile acids affect liver cell functions, such as biotransformation through CYP enzymes. In hepatitis B virus transgenic mice, a UDCA-rich diet promoted hepatocyte proliferation and tumor growth. Hepatologists advise against using UDCA in patients with severe obstructive cholangiopathies. Given the foregoing, new medications are required to treat these illnesses.

Methods

Twenty-four male Wistar albino rats were separated into three groups (8 rats for each group): negative control group I, positive control group II (ANIT-induced cholestasis), and treatment group III (Cil and ANIT). The mRNA and protein expression levels of FXR, small heterodimer partner (SHP), bile salt export pump (BSEP), nuclear factor erythroid 2-related factor 2 (NRF2), hepatocyte nuclear factor 1α (HNF1α), sirtuin 1 (SIRT1), NADPH dehydrogenase-quinone-1 (NQO-1), and heme oxygenase-1 (HO-1) were assessed post euthanasia. Additionally, other tissue oxidative stress markers were measured.

Results

Cil significantly increased the mRNA expression levels of FXR, SHP, BSEP, HNF1α, and NRF2 and the protein expression levels of FXR, BSEP, SIRT1, NQO-1, and HO-1 in the treatment group compared with those in the positive control group. Additionally, Cil decreased the oxidative stress level compared with that in the ANIT-treated group.

Conclusion

The results suggest that Cil effectively treats cholestasis by affecting the FXR signaling system and the NRF2 pathway.

HPPE Activates NRF2 Signaling by Liberating Heavy Metal Stores

The Cap'n'collar transcription factor BACH1 represses the transcription of gene products involved in oxidative stress protection. Accordingly, agents capable of inhibiting the activity of BACH1 would be of keen interest in treating several autoimmune and age-related diseases. Here, we report that a previously annotated BACH1 inhibitor, HPPE, does not inhibit BACH1 but instead activates a NRF2 driven transcription program that is dependent on the canonical cysteine sensors of NRF2 inhibitory protein KEAP1. Mechanistically, HPPE acts as an ionophore, liberating cellular Zn2+ stores and inducing non-lethal levels of reactive oxygen species, resulting in KEAP1 inactivation. These data provide a surprising mechanism by which HPPE acts in cells and suggest that inducing small amounts of cellular stress may be a viable mechanism for activating NRF2 therapeutically.

Protective effects of black ginseng on testicular toxicity induced by Di-n-butyl phthalate in rats

Di-n-butyl phthalate (DBP) is a phthalate-based material used as a plasticizer to soften polyvinyl chloride, and classified as an endocrine disruptor with antiandrogen effects. Exposure to DBP induces oxidative stress in rat testes, resulting in testicular toxicity. Black ginseng (BG) exhibits a higher antioxidant activity than white or red ginseng following repeated heat treatment and processing. This study aimed to investigate whether the antioxidant activity of BG might protect against DBP-induced testicular toxicity in juvenile Sprague-Dawley rats. A significant decrease in testicular weight was observed in most groups treated with DBP alone or in combination with BG. However, a significant testicular weight increase was detected after exposure to BG (10 ml/kg) + DBP (500 mg/kg). The epididymal weight was significantly reduced with associated histological changes including irregular arrangement, atrophy of seminiferous tubules and Sertoli cells, and Leydig cell damage following exposure to DBP alone as well as BG (2.5 ml/kg) + DBP (500 mg/kg). However, no marked changes were observed in the shape of seminiferous tubules in control and BG + DBP groups. A significant decrease in serum testosterone levels was found after exposure to DBP, but no marked alterations in the BG + DBP groups. Protein expression levels of nuclear factor erythroid-derived 2-related factor (Nrf2), NAD(P)H dehydrogenase 1 (NQO1), and, heme oxygenase-1; (HO-1) were significantly higher following DBP treatment, but lowered in the BG + DBP groups. Evidence indicates that BG exerts a protective effect against DBP-induced testicular toxicity in rats.

p62/SQSTM1 in cancer: phenomena, mechanisms, and regulation in DNA damage repair

The multidomain protein cargo adaptor p62, also known as sequestosome 1, serves as a shuttling factor and adaptor for the degradation of substrates via the proteasome and autophagy pathways. Regarding its structure, p62 is composed of several functional domains, including the N-terminal Phox1 and Bem1p domains, a ZZ-type zinc finger domain, a LIM protein-binding domain that contains the tumor necrosis factor receptor-associated factor 6 (TRAF6) binding region, two nuclear localization signals (NLS 1/2), a nuclear export signal (NES), the LC3-interacting region (LIR), a Kelch-like ECH-associated protein 1 (KEAP1)-interacting region, and a ubiquitin-associated (UBA) domain. Recent studies have highlighted the critical role of p62 in the development and progression of various malignancies. Overexpression and/or impaired degradation of p62 are linked to the initiation and progression of numerous cancers. While p62 is primarily localized in the cytosol and often considered a cytoplasmic protein, most of the existing literature focuses on its cytoplasmic functions, leaving its nuclear roles less explored. However, an increasing body of research has uncovered p62's involvement in the cellular response to DNA damage. In this review, we summarize the current understanding of p62's molecular functions in malignancies, with particular emphasis on its role in DNA damage repair, highlighting the latest advances in this field.

4-Hydroxy-2-nonenal causes nuclear accumulation of p62 by inhibiting Xpo1 and promoting the proteolytic pathway in the nucleus

p62, an adapter protein involved in selective autophagy, is mainly found in the cytoplasm under normal conditions. Because p62 has nuclear localization signal (NLS) and a nuclear export signal, it has been suggested that p62 shuttles between the nucleus and cytoplasm. We studied the effect of 4-hydroxy-nonenal (4-HNE), an endogenous lipid peroxidation product, on intracellular p62 distribution in mouse embryonic fibroblasts. We found that treatment of 4-HNE causes p62 translocation from the cytoplasm to the nucleus. Further analysis revealed that 4-HNE directly binds to exportin-1 (Xpo1), essential protein for nuclear export of various proteins. Further analysis 4-HNE enhanced intranuclear EGFP-NLS-CL1 degradation in a p62-dependent manner. Our results suggest that 4-HNE changes p62 localization to the nucleus by inhibiting Xpo1 and might affect intranuclear protein quality control.

Model organisms for investigating the functional involvement of NRF2 in non-communicable diseases

Non-communicable chronic diseases (NCDs) are most commonly characterized by age-related loss of homeostasis and/or by cumulative exposures to environmental factors, which lead to low-grade sustained generation of reactive oxygen species (ROS), chronic inflammation and metabolic imbalance. Nuclear factor erythroid 2-like 2 (NRF2) is a basic leucine-zipper transcription factor that regulates the cellular redox homeostasis. NRF2 controls the expression of more than 250 human genes that share in their regulatory regions a cis-acting enhancer termed the antioxidant response element (ARE). The products of these genes participate in numerous functions including biotransformation and redox homeostasis, lipid and iron metabolism, inflammation, proteostasis, as well as mitochondrial dynamics and energetics. Thus, it is possible that a single pharmacological NRF2 modulator might mitigate the effect of the main hallmarks of NCDs, including oxidative, proteostatic, inflammatory and/or metabolic stress. Research on model organisms has provided tremendous knowledge of the molecular mechanisms by which NRF2 affects NCDs pathogenesis. This review is a comprehensive summary of the most commonly used model organisms of NCDs in which NRF2 has been genetically or pharmacologically modulated, paving the way for drug development to combat NCDs. We discuss the validity and use of these models and identify future challenges.

Supplementation with carnosine, a food-derived bioactive dipeptide, alleviates dexamethasone-induced oxidative stress and bone impairment via the NRF2 signaling pathway

BACKGROUND

Carnosine, a natural bioactive dipeptide derived from meat muscle, possesses strong antioxidant properties. Dexamethasone, widely employed for treating various inflammatory diseases, raises concerns regarding its detrimental effects on bone health. This study aimed to investigate the protective effects of carnosine against dexamethasone-induced oxidative stress and bone impairment, along with its underlying mechanisms, utilizing chick embryos and a zebrafish model in vivo, as well as MC3T3-E1 cells in vitro.

RESULTS

Our findings revealed that carnosine effectively mitigated bone injury in dexamethasone-exposed chick embryos, accompanied by reduced oxidative stress. Further investigation demonstrated that carnosine alleviated impaired osteoblastic differentiation in MC3T3-E1 cells and zebrafish by suppressing the excessive production of reactive oxygen species (ROS) and enhancing the activity of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPX). Moreover, mechanistic studies elucidated that carnosine promoted the expression and nuclear translocation of nuclear factor erythroid 2-related factor 2 (NRF2), thereby facilitating the transcription of its downstream antioxidant response elements, including heme oxyense-1 (HO-1), glutamate cysteine ligase modifier (GCLM), and glutamate cysteine ligase catalytic (GCLC) to counteract dexamethasone-induced oxidative stress.

CONCLUSION

Overall, this study underscores the potential therapeutic efficacy of carnosine in mitigating oxidative stress and bone damage induced by dexamethasone exposure, shedding light on its underlying mechanism of action by activating the NRF2 signaling pathway. © 2024 Society of Chemical Industry.

Inhibition of transcriptional regulation of detoxification genes contributes to insecticide resistance management in Spodoptera exigua

Synthetic insecticides have been widely used for the prevention and control of disease vectors and agricultural pests. However, frequent uses of insecticides have resulted in the development of insecticide resistance in these insect pests. The resistance adversely affects the efficacy of insecticides, and seriously reduces the lifespan of insecticides. Therefore, resistance management requires new strategies to suppress insecticide resistance. Here, we confirm that CncC/Maf are the key regulators of various detoxification genes involved in insecticide resistance in Spodoptera exigua. Then, we develop a cell screening platform to identify the natural compound inhibitors of CncC/Maf and determine that sofalcone can act as a CncC/Maf inhibitor in vitro and in vivo. Bioassay results showed that sofalcone significantly enhanced the toxicity (more than 3-fold) of chlorpyrifos and lambda-cyhalothrin against S. exigua larvae. Finally, we demonstrate that sofalcone can greatly improve the susceptibility of S. exigua larvae to insecticides by inhibiting the activity of the ROS/CncC-dependent detoxifying enzymes and downregulating the expression levels of detoxification genes. CncC/Maf inhibitors can be used as broad-spectrum synergists to overcome insecticide resistance in pest populations. Altogether, our results demonstrate that reduced expression of detoxification genes resulting from suppression of transcriptional regulation of these genes contributes to controlling insecticide resistance, which provides a very novel and high-efficiency green resistance management strategy.

Crosstalk between ferroptosis and autophagy: broaden horizons of cancer therapy

Ferroptosis and autophagy are two main forms of regulated cell death (RCD). Ferroptosis is a newly identified RCD driven by iron accumulation and lipid peroxidation. Autophagy is a self-degradation system through membrane rearrangement. Autophagy regulates the metabolic balance between synthesis, degradation and reutilization of cellular substances to maintain intracellular homeostasis. Numerous studies have demonstrated that both ferroptosis and autophagy play important roles in cancer pathogenesis and cancer therapy. We also found that there are intricate connections between ferroptosis and autophagy. In this article, we tried to clarify how different kinds of autophagy participate in the process of ferroptosis and sort out the common regulatory pathways between ferroptosis and autophagy in cancer. By exploring the complex crosstalk between ferroptosis and autophagy, we hope to broaden horizons of cancer therapy.

Heat stress induces oxidative stress and activates the KEAP1-NFE2L2-ARE pathway in reproduction-related cells

Heat stress negatively affects the reproductive function of in animals and humans. Although a relationship between heat and oxidative stress has been suggested, the underlying mechanism has not been sufficiently examined in reproduction-related cells. Therefore, we aimed to investigate whether heat stress induces oxidative stress using a variety of reproduction-related cells including bovine placental and cumulus-granulosa cells, human cell lines derived from cervical and endometrial cancers, and fibroblasts derived from endometrium. Quantitative polymerase chain reaction analysis showed that the expression levels of representative heat and oxidative stress-related genes were significantly increased in cells cultured at high temperatures compared with those in cells cultured at basal temperatures. Moreover, luciferase reporter assays showed that the reporter activity of the heat shock element and antioxidant responsive element (ARE) was increased in cells cultured at high temperatures compared with that in cells cultured at basal temperatures. Furthermore, the stability of nuclear factor erythroid 2 like 2 (NFE2L2), a master regulator of the cellular stress response, increased under high temperatures. Point mutations in Kelch-like ECH-associated protein 1 (KEAP1) cysteine residues reduced the luciferase activity. Our results suggest that heat stress induces oxidative stress and that the KEAP1-NFE2L2-ARE pathway may play a protective role in reproduction-related cells against heat stress.

Naoqing formula alleviates acute ischaemic stroke-induced ferroptosis via activating Nrf2/xCT/GPX4 pathway

Backgrounds

Ferroptosis is a form of regulated cell death. The accumulation of iron in the brain is linked to trigger ferroptosis after an ischaemic stroke (IS). Naoqing formula (NQ) is a traditional Chinese medicine metabolites with the clinical function of activating blood circulation, which is applied to treat IS clinically in China.

Methods

Mice and SH-SY5Y cells were utilized to investigate the protective effects and the underlying mechanism of NQ against middle cerebral artery occlusion (MCAO) induced acute ischaemic stroke (AIS) and neuronal cellular ferroptosis caused by ferroptosis inducer Erastin in vitro and in vivo. Utilizing molecular biological techniques, transcriptomics, and proteomics analyses, the role of NQ in Nrf2 regulation and ferroptosis was evaluated through the pharmacologic inhibition of Nrf2.

Results

NQ attenuated AIS-induced neuronal damage and cerebral infarction by increasing cortical blood flow (CBF). Transcriptomics and proteomics analyses revealed that NQ might regulate lipid and iron metabolism through Nrf2 pathway. Additionally, NQ can protect AIS from ferroptosis by reducing oxidative stress and iron overload. Meanwhile, Nrf2, solute carrier family 7 member 11 (SLC7A11; also known as xCT) and glutathione peroxidase 4 (GPX4) were upregulated in NQ-treated AIS mice. Consistent with the results in vivo, NQ led to ferroptosis resistance upon exposure to a ferroptosis-inducing compound through activation of Nrf2/xCT/GPX4 pathway in vitro. Notably, in vivo inhibition of Nrf2 expression by ML385 aggravated the ferroptotic events and weakened the neuroprotective effect of NQ as well as subsequently reduced the expression of xCT and GPX4.

Conclusion

This study demonstrated that NQ protected against AIS via suppression of ferroptosis and oxidative stress, which were largely dependent on the upregulation of Nrf2 pathway.

Role of NRF2 in Pathogenesis of Alzheimer's Disease

Alzheimer's disease (AD) is a polygenic, multifactorial neurodegenerative disorder and remains the most prevalent form of dementia, globally. Despite decades of research efforts, there is still no effective cure for this debilitating condition. AD research has increasingly focused on transcription factor NRF2 (nuclear factor erythroid 2-related factor 2) as a potential therapeutic target. NRF2 plays a crucial role in protecting cells and tissues from environmental stressors, such as electrophiles and reactive oxygen species. Recently, an increasing number of studies have demonstrated that NRF2 is a key regulator in AD pathology. NRF2 is highly expressed in microglia, resident macrophages in the central nervous system, and contributes to neuroinflammation, phagocytosis and neurodegeneration in AD. NRF2 has been reported to modulate microglia-induced inflammation and facilitate the transition from homeostatic microglia to a disease-associated microglia subset. Genetic and pharmacological activation of NRF2 has been demonstrated to improve cognitive function. Here, we review the current understanding of the involvement of NRF2 in AD and the critical role that NRF2 plays in microglia in the context of AD. Our aim is to highlight the potential of targeting NRF2 in the microglia as a promising therapeutic strategy for mitigating the progression of AD.

Salidroside alleviates ferroptosis in FAC-induced Age-related macular degeneration models by activating Nrf2/SLC7A11/GPX4 axis

INTRODUCTION

Age-related macular degeneration (AMD) is a significant contributor to irreversible impairment in visual capability, particularly in its non-neovascular (dry) form. Ferroptosis, an emerging form of programmed necrosis, involves generating lipid peroxidation (LOS) through free iron and reactive oxygen species (ROS). Salidroside, a glycoside from Rhodiola rosea, known for anti-inflammatory and antioxidant properties. The research aim was exploring whether ferroptosis exists in dry AMD pathogenesis and elucidate salidroside's protective mechanisms against ferroptosis in AMD murine models and ARPE-19 cells.

METHODS

ARPE-19 cells were treated with varying concentrations of ferrous ammonium citrate (FAC) and salidroside. In an in vivo model, C57BL/6 mice were administered intraperitoneal injections of salidroside for 7 consecutive days, followed by an intravitreal injection (IVT) of FAC. After 7 days, the eyeballs were harvested for subsequent analyses. Ferroptosis markers were assessed using western blotting, immunofluorescence staining, and flow cytometry. To further elucidate the modulatory role of Nrf2 in ferroptosis, ARPE-19 cells were transfected with si-Nrf2.

RESULTS

In vitro, FAC-treated ARPE-19 cells exhibited reduced viability, decreased mitochondrial membrane potential (MMP), and accumulation of iron and lipid peroxidation (LOS) products. In vivo, FAC administration by IVT led to outer nuclear layer thinning and compromised tight junctions in RPE cells. The GPX4, Nrf2, and SLC7A11 expressions were downregulated both in vitro and in vivo. Salidroside upregulated Nrf2 and ameliorated these outcomes, but its effects were attenuated in ARPE-19 cells transfected with si-Nrf2.

CONCLUSION

Our study establishes that FAC induces RPE cell ferroptosis within dry AMD, and salidroside exerts therapeutic effects by triggering Nrf2/SLC7A11/GPX4 signaling axis.

Quercetin protects the liver of broiler chicken against oxidative stress and apoptosis induced by ochratoxin A

Ochratoxin A (OTA) is a mycotoxin that causes major health concerns in human and animals. Quercetin (QUE) is a flavonoid that possesses antioxidant, anti-inflammatory and anti-apoptotic properties. This report aims to investigate the ameliorative effects of QUE against OTA-induced hepatotoxicity in broiler chicken. Forty broiler chicks were equally allocated into 4 groups: Group I (control), Group II (OTA), Group III (QUE) and Group IV (OTA + QUE). OTA (0.5 mg/kg) and QUE (0.5 g/kg) were incorporated into the chicken feed for 42 days. The results presented a significant decrease in body weight and elevation in feed conversion ratio, and a significant elevation of the activities of serum alanine aminotransferase and aspartate aminotransferase enzymes in the OTA birds. Additionally, there was a significant decrease in catalase activity and reduced glutathione content and a significant elevation in malondialdehyde level in the liver of OTA-exposed birds. Various hepatocellular lesions were also noticed in the OTA-exposed birds. OTA exposure up-regulated the phosphatase and tensin homologue (PTEN) and the pro-apoptotic genes and down-regulated the anti-apoptotic genes in the liver. The addition of QUE ameliorated most of the hepatotoxic effects of OTA.

Norlignans and Phenolics from Curculigo capitulata and Their Neuroprotection Against Glutamate-Induced Oxidative Injury in SH-SY5Y Cells

The herb Curculigo capitulata (Lour.) Ktze is widely distributed in southern and southwestern China. The Curculigo genus and its primary chemical constituents exhibit remarkable antidepressant activities. To investigate the chemical constituents and potential health benefits of C. capitulata, a phytochemical study was conducted. In this study, seven new compounds (capitugenin A-G), including three new norlignans (1-3), a new chalcone dimer (4), a new hemiacetal (5), two novel pyrrolidine-based compounds (6 and 7), including one identified as a natural product (7), and nineteen known compounds (8-26), were isolated from C. capitulata. The chemical structures and absolute configurations of Compounds 1-7 were elucidated via comprehensive spectroscopic data analyses. The neuroprotective effects of Compounds 1-26 against glutamate-induced cell death were tested in the human neuroblastoma cell line SH-SY5Y. Compounds 1, 3, 6, 8, 11, and 17 showed significant neuroprotective effects, with protection rates ranging from 29.4 to 52.8% at concentrations ranging from 5 to 40 μM. Western blot analysis indicated that Compound 3 exerted a protective effect by regulating the expression of Nrf2/HO-1.

Targeting nuclear factor erythroid 2-related factor 2-regulated ferroptosis to treat nervous system diseases

By critically examining the work, we conducted a comprehensive bibliometric analysis on the role of nuclear factor erythroid 2-related factor 2 (NRF2) in nervous system diseases. We also proposed suggestions for future bibliometric studies, including the integration of multiple websites, analytical tools, and analytical approaches, The findings presented provide compelling evidence that ferroptosis is closely associated with the therapeutic challenges of nervous system diseases. Targeted modulation of NRF2 to regulate ferroptosis holds substantial potential for effectively treating these diseases. Future NRF2-related research should not only focus on discovering new drugs but also on designing rational drug delivery systems. In particular, nanocarriers offer substantial potential for facilitating the clinical translation of NRF2 research and addressing existing issues related to NRF2-related drugs.

Protocatechuic acid relieves ferroptosis in hepatic lipotoxicity and steatosis via regulating NRF2 signaling pathway

Ferroptosis represents a newly programmed cell death, and the process is usually accompanied with iron-dependent lipid peroxidation. Importantly, ferroptosis is implicated in a myriad of diseases. Recent literature suggests a potential position of ferroptosis in the pathogenesis of metabolic dysfunction-associated fatty liver disease (MAFLD), the most widespread liver ailment worldwide. Intriguingly, several functional genes and metabolic pathways central to ferroptosis are regulated by nuclear factor erythroid-derived 2-like 2 (NRF2). In current work, we aim to identify protocatechuic acid (PCA), a primary metabolite of antioxidant polyphenols, as a potent NRF2 activator and ferroptosis inhibitor in the hepatic lipotoxicity and steatosis models. Herein, both NRF2+/+ and NRF2-/- cell lines and mice were used to analyze the importance of NRF2 in PCA function, and hepatic lipotoxicity and steatosis models were induced by palmitic acid and high-fat diet respectively. Our results indicated that ferroptosis was mitigated by PCA intervention in hepatic cells. Furthermore, PCA exhibited therapeutic efficacy against ferroptosis, as well as hepatic lipotoxicity and steatosis. The protective role of PCA was predominantly mediated through NRF2 activation, potentially elucidating a pivotal mechanism underlying PCA's therapeutic impact on MAFLD. Additionally, the augmented mitochondrial TCA cycle activity observed in hepatic lipotoxicity and steatosis models was ameliorated by PCA, in part via NRF2-dependent pathways, further bolstering PCA's anti-ferroptosis properties. Collectively, our findings underscore PCA's potential in alleviating hepatic ferroptosis, lipotoxicity and steatosis via inducing activation of NRF2 signaling pathway, offering a promising strategy for the therapy of MAFLD as well as related lipid metabolic disorders.

Human salivary histatin 1 regulating IP3R1/GRP75/VDAC1 mediated mitochondrial-associated endoplasmic reticulum membranes (MAMs) inhibits cell senescence for diabetic wound repair

RATIONALE

Difficulty in skin wound healing is a concern for diabetic patients across the world. Impaired mitochondrial dysfunction and aging-related vascular dysfunction in human umbilical vein endothelial cells (HUVECs) caused by oxidative stress are major impediments to diabetic wound healing. However, research on skin repair at the mechanistic level by improving mitochondrial function and inhibiting oxidative stress-induced HUVEC senescence remains lacking.

METHODS AND RESULTS

Human saliva effectively inhibits the natural aging of HUVECs through immunodepletion experiments. Histatin 1 (Hst1), a short peptide comprising 38 amino acids, is the primary component of human saliva that prevents HUVEC aging. Based on in vitro findings, Hst1 decreased staining for senescence-associated β-galactosidase activity and expression of mediators of senescence signaling, including p53, p21, and p16. Mechanistically, HUVEC senescence is associated with Hst1-modulated nuclear factor Nrf2 signaling as Hst1 induces ERK-mediated Nrf2 nuclear translocation through NADPH oxidase-dependent ROS regulation, reinforced Nrf2 antioxidant response, and suppressed oxidative stress. RNA sequencing identified that the mitochondrial-related gene set was enriched in the Hst1 group. Coimmunoprecipitation indicated that Hst1 delayed hydrogen peroxide-induced HUVEC senescence by inhibiting mitochondria-associated endoplasmic reticulum (ER) membrane formation mediated by inositol 1,4,5-trisphosphate receptor 1-glucose-regulated protein 75-voltage-dependent anion channel 1 (VDAC1) complex interactions. Furthermore, in aging HUVECs, Hst1 treatment or VDAC1 silencing with small interfering RNA hindered calcium (Ca2+) transfer from the ER to the mitochondria, thereby ameliorating mitochondrial Ca2+ overload and restoring mitochondrial function. In an in vivo mouse model of diabetes mellitus skin defects, Hst1 facilitated wound healing by stimulating the new blood vessel formation and impeding the expression of senescent biomarkers.

CONCLUSIONS

This study proposes a theoretical solution that Hst1 can restore mitochondrial function by inhibiting oxidative stress or cellular senescence, thereby promoting angiogenesis and diabetic wound repair.

Tripartite motif 25 inhibits protein aggregate degradation during PRRSV infection by suppressing p62-mediated autophagy

Viral infection causes endoplasmic reticulum stress and protein metabolism disorder, influencing protein aggregates formation or degradation that originate from misfolded proteins. The mechanism by which host proteins are involved in the above process remains largely unknown. The present study found that porcine reproductive and respiratory syndrome virus (PRRSV) infection promoted the degradation of intracellular ubiquitinated protein aggregates via activating autophagy. The host cell E3 ligase tripartite motif-containing (TRIM)25 promoted the recruitment and aggregation of polyubiquitinated proteins and impeded their degradation caused by PRRSV. TRIM25 interacted with ubiquitinated aggregates and was part of the aggregates complex. Next, the present study investigated the mechanisms by which TRIM25 inhibited the degradation of protein aggregates, and it was found that TRIM25 interacted with both Kelch-like ECH-associated protein 1 (KEAP1) and nuclear factor E2-related factor 2 (Nrf2), facilitated the nuclear translocation of Nrf2 by targeting KEAP1 for K48-linked ubiquitination and proteasome degradation, and activated Nrf2-mediated p62 expression. Further studies indicated that TRIM25 interacted with p62 and promoted its K63-linked ubiquitination via its E3 ligase activity and thus caused impairment of its oligomerization, aggregation, and recruitment for the autophagic protein LC3, leading to the suppression of autophagy activation. Besides, TRIM25 also suppressed the p62-mediated recruitment of ubiquitinated aggregates. Activation of autophagy decreased the accumulation of protein aggregates caused by TRIM25 overexpression, and inhibition of autophagy decreased the degradation of protein aggregates caused by TRIM25 knockdown. The current results also showed that TRIM25 inhibited PRRSV replication by inhibiting the KEAP1-Nrf2-p62 axis-mediated autophagy. Taken together, the present findings showed that the PRRSV replication restriction factor TRIM25 inhibited the degradation of ubiquitinated protein aggregates during viral infection by suppressing p62-mediated autophagy.IMPORTANCESequestration of protein aggregates and their subsequent degradation prevents proteostasis imbalance and cytotoxicity. The mechanisms controlling the turnover of protein aggregates during viral infection are mostly unknown. The present study found that porcine reproductive and respiratory syndrome virus (PRRSV) infection promoted the autophagic degradation of ubiquitinated protein aggregates, whereas tripartite motif-containing (TRIM)25 reversed this process. It was also found that TRIM25 promoted the expression of p62 by activating the Kelch-like ECH-associated protein 1 (KEAP1) and nuclear factor E2-related factor 2 (Nrf2) pathway and simultaneously prevented the oligomerization of p62 by promoting its K63-linked ubiquitination, thus suppressing its recruitment of the autophagic adaptor protein LC3 and ubiquitinated aggregates, leading to the inhibition of PRRSV-induced autophagy activation and the autophagic degradation of protein aggregates. The present study identified a new mechanism of protein aggregate turnover during viral infection and provided new insights for understanding the pathogenic mechanism of PRRSV.

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.

Stress response regulation of mRNA translation: Implications for antioxidant enzyme expression in cancer

From tumorigenesis to advanced metastatic stages, tumor cells encounter stress, ranging from limited nutrient and oxygen supply within the tumor microenvironment to extrinsic and intrinsic oxidative stress. Thus, tumor cells seize regulatory pathways to rapidly adapt to distinct physiologic conditions to promote cellular survival, including manipulation of mRNA translation. While it is now well established that metastatic tumor cells must up-regulate their antioxidant capacity to effectively spread and that regulation of antioxidant enzymes is imperative to disease progression, relatively few studies have assessed how translation and the hijacking of RNA systems contribute to antioxidant responses of tumors. Here, we review the major stress signaling pathways involved in translational regulation and discuss how these are affected by oxidative stress to promote prosurvival changes that manipulate antioxidant enzyme expression. We describe how tumors elicit these adaptive responses and detail how stress-induced translation can be regulated by kinases, RNA-binding proteins, RNA species, and RNA modification systems. We also highlight opportunities for further studies focused on the role of mRNA translation and RNA systems in the regulation of antioxidant enzyme expression, which may be of particular importance in the context of metastatic progression and therapeutic resistance.

The Hippo Signaling Pathway, Reactive Oxygen Species Production, and Oxidative Stress: A Two-Way Traffic Regulation

The Hippo signaling pathway is recognized for its significant role in cell differentiation, proliferation, survival, and tissue regeneration. Recently, the Hippo signaling pathway was also found to be associated with oxidative stress and reactive oxygen species (ROS) regulation, which are important in the regulation of cell survival. Studies indicate a correlation between components of the Hippo signaling pathway, including MST1, YAP, and TAZ, and the generation of ROS. On the other hand, ROS and oxidative stress can activate key components of the Hippo signaling pathway. For example, ROS production activates MST1, which subsequently phosphorylates FOXO3, leading to apoptotic cell death. ROS was also found to regulate YAP, in addition to MST1/2. Oxidative stress and ROS formation can impair lipids, proteins, and DNA, leading to many disorders, including aging, neurodegeneration, atherosclerosis, and diabetes. Consequently, understanding the interplay between the Hippo signaling pathway, ROS, and oxidative stress is crucial for developing future disease management strategies. This paper aimed to review the association between the Hippo signaling pathway, regulation of ROS production, and oxidative stress to provide beneficial information in understanding cell function and pathological processes.

Role of Irisin in exercise training-regulated endoplasmic reticulum stress, autophagy and myogenesis in the skeletal muscle after myocardial infarction

Patients with heart failure (HF) are often accompanied by skeletal muscle abnormalities, which can lead to exercise intolerance and compromise daily activities. Irisin, an exercise training (ET) -induced myokine, regulates energy metabolism and skeletal muscle homeostasis. However, the precise role of Irisin in the benefits of ET on inhibiting skeletal muscle atrophy, particularly on endoplasmic reticulum (ER) stress, autophagy, and myogenesis following myocardial infarction (MI) remains unclear. In this study, we investigated the expression of Irisin protein in wild-type mice with MI, and assessed its role in the beneficial effects of ET using an Fndc5 knockout mice. Our findings revealed that MI reduced muscle fiber cross-sectional area (CSA), while downregulating the expression of Irisin, PGC-1α and SOD1. Concurrently, MI elevated the levels of ER stress and apoptosis, and inhibited autophagy in skeletal muscle. Conversely, ET mitigated ER stress and apoptosis in the skeletal muscle of infarcted mice. Notably, Fndc5 knockout worsened MI-induced ER stress and apoptosis, suppressed autophagy and myogenesis, and abrogated the beneficial effects of ET. In conclusion, our findings highlight the role of Irisin in the ET-mediated alleviation of skeletal muscle abnormalities. This study provides valuable insights into MI-induced muscle abnormalities and enhances our understanding of exercise rehabilitation mechanisms in clinical MI patients.

Functional characterization of large yellow croaker (Larimichthys crocea) Peroxiredoxin IV (PrxIV) gene promoter

Peroxiredoxin IV (PrxIV), which possesses an N-terminal signal peptide, is the only secretable protein in Prx family. PrxIV can protect cells against reactive oxygen species (ROS) and act as a DAMP to promote infection-independent immune response. However, the characterization and regulation of promoters of PrxIV genes are rarely reported. In this study, a 1511-bp 5'-flanking sequence of large yellow croaker (Larimichthys crocea) PrxIV (LcPrxIV) was cloned and characterized. DNA truncation combined with luciferase activity assay revealed that a fragment of -781/+20 contained in the plasmid LcPrxIV-P3 exhibited the highest promoter activity. It could initiate the luciferase expression up to 44.6-fold when compared to control plasmid pGL3-Basic. TFSEARCH analysis revealed many recognizing sequences of transcriptional factors exist within this 1511-bp sequence, including Foxo and CREB. Altogether, four putative binding sites located in three recognizing sequences of CREB were identified. Notably, co-transfection of LcPrxIV-P3 with LcCREB led to a significant 2.48-fold increase of the LcPrxIV-P3 promoter activity (P<0.01). Furthermore, the mutation at putative binding sites A, B, and all four sites of CREB in the LcPrxIV-P3 caused the significant decrease of activation on LcPrxIV-P3 promoter activity, suggesting these two sites may be the main binding sites of CREB in LcPrxIV promoter. In addition, the oxidative stress caused by hydrogen peroxide, rather than immune stimuli such as Poly (I: C), LPS, LTA, or PGN could lead to the elevation of LcPrxIV-P3 promoter activity. When the concentration of hydrogen peroxide reached 500 μM, the promoter activity of LcPrxIV-P3 could be up-regulated to 1.47-fold, which was extremely significantly different from the control (P<0.001). These results help to elucidate the regulatory mechanisms of LcPrxIV gene expression, and the role of LcPrxIV in protecting cells against oxidative stress or in oxidoreduction-dependent signal transduction.

Sensor systems of KEAP1 uniquely detecting oxidative and electrophilic stresses separately In vivo

In the KEAP1-NRF2 stress response system, KEAP1 acts as a sensor for oxidative and electrophilic stresses through formation of S-S bond and C-S bond, respectively. Of the many questions left related to the sensor activity, following three appear important; whether these KEAP1 sensor systems are operating in vivo, whether oxidative and electrophilic stresses are sensed by the similar or distinct systems, and how KEAP1 equips highly sensitive mechanisms detecting oxidative and electrophilic stresses in vivo. To address these questions, we conducted a series of analyses utilizing KEAP1-cysteine substitution mutant mice, conditional selenocysteine-tRNA (Trsp) knockout mice, and human cohort whole genome sequence (WGS) data. Firstly, the Trsp-knockout provokes severe deficiency of selenoproteins and compensatory activation of NRF2. However, mice lacking homozygously a pair of critical oxidative stress sensor cysteine residues of KEAP1 fail to activate NRF2 in the Trsp-knockout livers. Secondly, this study provides evidence for the differential utilization of KEAP1 sensors for oxidative and electrophilic stresses in vivo. Thirdly, theoretical calculations show that the KEAP1 dimer equips quite sensitive sensor machinery in which modification of a single molecule of KEAP1 within the dimer is sufficient to affect the activity. WGS examinations of rare variants identified seven non-synonymous variants in the oxidative stress sensors in human KEAP1, while no variant was found in electrophilic sensor cysteine residues, supporting the fail-safe nature of the KEAP1 oxidative stress sensor activity. These results provide valuable information for our understanding how mammals respond to oxidative and electrophilic stresses efficiently.

Mechanistic Insights and Potential Therapeutic Implications of NRF2 in Diabetic Encephalopathy

Diabetic encephalopathy (DE) is a complication of diabetes, especially type 2 diabetes (T2D), characterized by damage in the central nervous system and cognitive impairment, which has gained global attention. Despite the extensive research aimed at enhancing our understanding of DE, the underlying mechanism of occurrence and development of DE has not been established. Mounting evidence has demonstrated a close correlation between DE and various factors, such as Alzheimer's disease-like pathological changes, insulin resistance, inflammation, and oxidative stress. Of interest, nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor with antioxidant properties that is crucial in maintaining redox homeostasis and regulating inflammatory responses. The activation and regulatory mechanisms of NRF2 are a relatively complex process. NRF2 is involved in the regulation of multiple metabolic pathways and confers neuroprotective functions. Multiple studies have provided evidence demonstrating the significant involvement of NRF2 as a critical transcription factor in the progression of DE. Additionally, various molecules capable of activating NRF2 expression have shown potential in ameliorating DE. Therefore, it is intriguing to consider NRF2 as a potential target for the treatment of DE. In this review, we aim to shed light on the role and the possible underlying mechanism of NRF2 in DE. Furthermore, we provide an overview of the current research landscape and address the challenges associated with using NRF2 activators as potential treatment options for DE.

Pretreatment with aqueous Moringa oleifera Lam. leaf extract prevents cadmium-induced hepatotoxicity by improving cellular antioxidant machinery and reducing cadmium accumulation

Cadmium (Cd) is a highly harmful pollutant that poses a serious threat to human health. The liver is the primary organ for Cd accumulation, and Cd-induced hepatotoxicity has been shown to be strongly correlated with an oxidative imbalance in hepatocytes. Our previous studies in the eukaryotic model organism Saccharomyces cerevisiae revealed that not only co-treatment but also pretreatment with aqueous Moringa oleifera Lam. leaf extract (AMOLE) effectively mitigated Cd toxicity by reducing intracellular Cd accumulation and Cd-mediated oxidative stress. In this study, we therefore investigated the preventive effect of AMOLE against Cd toxicity in human HepG2 hepatocytes. The results showed that, similar to the case of the yeast model, pretreatment with AMOLE prior to Cd exposure also significantly inhibited Cd-induced oxidative stress in HepG2 cells. Untargeted LC-MS/MS-based metabolomic analysis of AMOLE revealed that its major phytochemical constituents were organic acids, particularly phenolic acids and carboxylic acids. Additionally, DPPH-HPTLC fingerprints suggested that quercetin and other flavonoids possibly contribute to the antioxidant activities of AMOLE. Based on our findings, it appears that pretreatment with AMOLE prevented Cd-induced hepatotoxicity via three possible mechanisms: i) direct elimination of free radicals by AMOLE antioxidant compounds; ii) upregulation of antioxidant defensive machinery (GPx1, and HO-1) via Nrf2 signaling cascade to improve cellular antioxidant capacity; and iii) reduction of intracellular Cd accumulation, probably by suppressing Cd uptake. These data strongly suggest the high potential of AMOLE for clinical utility in the prevention of Cd toxicity.

The Nrf2-HO-1 system and inflammaging

Nrf2 is a master transcriptional regulator of a number of genes involved in the adaptive response to oxidative stress. Among the genes upregulated by Nrf2, heme oxygenase-1 (HO-1) has received significant attention, given that the products of HO-1-induced heme catabolism have well established antioxidant and anti-inflammatory properties. This is evidenced in numerous models of inflammatory and autoimmune disease whereby induction of HO-1 expression or administration of tolerable amounts of HO-1 reaction products can ameliorate disease symptoms. Unsurprisingly, Nrf2 and HO-1 are now considered viable drug targets for a number of conditions. In recent years, the term 'inflammaging' has been used to describe the low-grade chronic inflammation observed in aging/aged cells. Increased oxidative stress is also a key factor associated with aging and there is convincing evidence that Nrf2, not only declines with age, but that Nrf2 and HO-1 can reduce cellular senescence and the senescence-associated secretory phenotype (SASP) which is now considered an underlying driver of age-related inflammatory disease. In this review, we describe the role of oxidative stress in 'inflammaging' and highlight the potential anti-aging properties of the Nrf2-HO-1 system. We also highlight established and newly emerging Nrf2 activators and their therapeutic application in age-related disease.

UBE2C regulates the KEAP1/NRF2 signaling pathway to promote the growth of gastric cancer by inhibiting autophagy

Gastric cancer (GC) is one of the most common malignant tumors in the world, ranking fourth in incidence and second in mortality among malignant tumors. In recent years, there has been some progress in biological treatment and targeted treatment for gastric cancer, but the prognosis for gastric cancer patients remains pessimistic, and the molecular mechanisms involved are not yet clear. In this study, bioinformatics analysis showed that Ubiquitin-conjugating enzyme E2C(UBE2C) was abnormally expressed in various types of cancer. Furthermore, UBE2C protein and mRNA expression was significantly elevated in gastric cancer tissues and cells. Silencing UBE2C significantly inhibited the proliferation and migration of gastric cancer cells. Mechanistically, UBE2C overexpression inhibited gastric cancer cell autophagy, leading to the accumulation of p62. Furthermore, immunoprecipitation results showed that UBE2C overexpression promoted the interaction between p62 and KEAP1, while inhibiting the binding of NRF2 to KEAP1, thereby weakening the ubiquitination and degradation of NRF2. In addition, the silencing of UBE2C leads to a reduction in the nuclear accumulation of NRF2. Importantly, the NRF2 activator TBHQ reversed the inhibition of gastric cancer cell proliferation and migration caused by the silencing of UBE2C. In summary, our study provides new insights into the molecular mechanisms of UBE2C in anti-cancer therapy.

Hypoxia-induced epigenetic regulation of breast cancer progression and the tumour microenvironment

The events that control breast cancer progression and metastasis are complex and intertwined. Hypoxia plays a key role both in oncogenic transformation and in fueling the metastatic potential of breast cancer cells. Here we review the impact of hypoxia on epigenetic regulation of breast cancer, by interfering with multiple aspects of the tumour microenvironment. The co-dependent relationship between oxygen depletion and metabolic shift to aerobic glycolysis impacts on a range of enzymes and metabolites available in the cell, promoting posttranslational modifications of histones and chromatin, and changing the gene expression landscape to facilitate tumour development. Hormone signalling, particularly through ERα, is also tightly regulated by hypoxic exposure, with HIF-1α expression being a prognostic marker for therapeutic resistance in ER+ breast cancers. This highlights the strong need to understand the hypoxia-endocrine signalling axis and exploit it as a therapeutic target. Furthermore, hypoxia has been shown to enhance metastasis in TNBC cells, as well as promoting resistance to taxanes, radiotherapy and even immunotherapy through microRNA regulation and changes in histone packaging. Finally, several other mediators of the hypoxic response are discussed. We highlight a link between ionic dysregulation and hypoxia signalling, indicating a potential connection between HIF-1α and tumoural Na+ accumulation which would be worth further exploration; we present the role of Ca2+ in mediating hypoxic adaptation via chromatin remodelling, transcription factor recruitment and changes in signalling pathways; and we briefly summarise some of the findings regarding vesicle secretion and paracrine induced epigenetic reprogramming upon hypoxic exposure in breast cancer. By summarising these observations, this article highlights the heterogeneity of breast cancers, presenting a series of pathways with potential for therapeutic applications.

Ferroptosis in the adjuvant treatment of lung cancer-the potential of selected botanical drugs and isolated metabolites

Ferroptosis represents a distinct form of cell death that is not associated with necrosis, autophagy, apoptosis, or pyroptosis. It is characterised by intracellular iron-dependent lipid peroxidation. The current literature indicates that a number of botanical drugs and isolated metabolites can modulate ferroptosis, thereby exerting inhibitory effects on lung cancer cells or animal models. The aim of this review is to elucidate the mechanisms through which botanical drugs and isolated metabolites regulate ferroptosis in the context of lung cancer, thereby providing potential insights into lung cancer treatment. It is crucial to highlight that these preclinical findings should not be interpreted as evidence that these treatments can be immediately translated into clinical applications. In the future, we will continue to study the pharmacology, pharmacokinetics and toxicology of these drugs, as well as evaluating their efficacy and safety in clinical trials, with the aim of providing new approaches to the development of new agents for the treatment of lung cancer.

A First Metabolite Analysis of Norfolk Island Pine Resin and Its Hepatoprotective Potential to Alleviate Methotrexate (MTX)-Induced Hepatic Injury

Drug-induced liver injury (DILI) represents a significant clinical challenge characterized by hepatic dysfunction following exposure to diverse medications. Methotrexate (MTX) is a cornerstone in treating various cancers and autoimmune disorders. However, the clinical utility of MTX is overshadowed by its ability to induce hepatotoxicity. The current study aims to elucidate the hepatoprotective effect of the alcoholic extract of Egyptian Araucaria heterophylla resin (AHR) on MTX-induced liver injury in rats. AHR (100 and 200 mg/kg) significantly decreased hepatic markers (AST, ALT, and ALP), accompanied by an elevation in the antioxidant's markers (SOD, HO-1, and NQO1). AHR extract also significantly inhibited the TGF-β/NF-κB signaling pathway as well as the downstream cascade (IL-6, JAK, STAT-3, and cyclin D). The extract significantly reduced the expression of VEGF and p38 with an elevation in the BCL2 levels, in addition to a significant decrease in the IL-1β and TNF-α levels, with a prominent effect at a high dose (200 mg/kg). Using LC-HRMS/MS analysis, a total of 43 metabolites were tentatively identified, and diterpenes were the major class. This study presents AHR as a promising hepatoprotective agent through inhibition of the TGF-β/NF-κB and JAK/STAT3 pathways, besides its antioxidant and anti-inflammatory effects.

Culture of Bovine Aortic Endothelial Cells in Galactose Media Enhances Mitochondrial Plasticity and Changes Redox Sensing, Altering Nrf2 and FOXO3 Levels

Understanding the complex biological processes of cells in culture, particularly those related to metabolism, can be biased by culture conditions, since the choice of energy substrate impacts all of the main metabolic pathways. When glucose is replaced by galactose, cells decrease their glycolytic flux, working as an in vitro model of limited nutrient availability. However, the effect of these changes on related physiological processes such as redox control is not well documented, particularly in endothelial cells, where mitochondrial oxidation is considered to be low. We evaluated the differences in mitochondrial dynamics and function in endothelial cells exposed to galactose or glucose culture medium. We observed that cells maintained in galactose-containing medium show a higher mitochondrial oxidative capacity, a more fused mitochondrial network, and higher intercellular coupling. These factors are documented to impact the cellular response to oxidative stress. Therefore, we analyzed the levels of two main redox regulators and found that bovine aortic endothelial cells (BAEC) in galactose media had higher levels of FOXO3 and lower levels of Nrf2 than those in glucose-containing media. Thus, cultures of endothelial cells in a galactose-containing medium may provide a more suitable target for the study of in vitro mitochondrial-related processes than those in glucose-containing media; the medium deeply influences redox signaling in these cells.

Nrf2 Deficiency Accelerates IL-17-Dependent Neutrophilic Airway Inflammation in Asthmatic Mice

Asthma is a heterogeneous disease that can be broadly classified into type 2, which is primarily steroid-sensitive and eosinophilic, and non-type 2, which is primarily steroid-resistant and neutrophilic. While the mechanisms leading to the development of molecular-targeted therapies for type 2 asthma are being elucidated, much remains to be learned about non-type 2 asthma. To investigate the role of oxidative stress in refractory allergic airway inflammation, we compared asthma models generated by immunizing wild-type and nuclear factor erythroid-2-related factor 2 (Nrf2)-deficient mice with the house dust mite antigen. Both asthma models had similar levels of airway inflammation and hyperresponsiveness, but the Nrf2-deficient mice had increased oxidative stress and exacerbated neutrophilic airway inflammation compared with the wild-type mice. Type 2 cytokines and the expression of GATA3, a transcription factor that is important for Th2 cell differentiation, had decreased in Nrf2-deficient mice compared with the wild-type mice, whereas helper T (Th) 17 cytokines and the expression of RORγt, which is important for Th17 cell differentiation, had increased. Furthermore, the neutrophilic airway inflammation caused by Nrf2 deficiency was ameliorated by interleukin (IL)-17 neutralization. We have concluded that the disruption of the Nrf2-mediated antioxidant defense system contributed to the induction of Th17 differentiation and exacerbated allergic neutrophilic airway inflammation.

Machine Learning of Three-Dimensional Protein Structures to Predict the Functional Impacts of Genome Variation

Research in the human genome sciences generates a substantial amount of genetic data for hundreds of thousands of individuals, which concomitantly increases the number of variants of unknown significance (VUS). Bioinformatic analyses can successfully reveal rare variants and variants with clear associations with disease-related phenotypes. These studies have had a significant impact on how clinical genetic screens are interpreted and how patients are stratified for treatment. There are few, if any, computational methods for variants comparable to biological activity predictions. To address this gap, we developed a machine learning method that uses protein three-dimensional structures from AlphaFold to predict how a variant will influence changes to a gene's downstream biological pathways. We trained state-of-the-art machine learning classifiers to predict which protein regions will most likely impact transcriptional activities of two proto-oncogenes, nuclear factor erythroid 2 (NFE2L2)-related factor 2 (NRF2) and c-Myc. We have identified classifiers that attain accuracies higher than 80%, which have allowed us to identify a set of key protein regions that lead to significant perturbations in c-Myc or NRF2 transcriptional pathway activities.

Cognitive Impairment Induced by Gestational Diabetes: The Role of Oxidative Stress

BACKGROUND

Cognitive impairment is defined as a neurological condition that alters multiple cerebral functions such as reasoning, memory, concentration, and association, among others. It has found to be widely correlated with several factors such as oxidative stress. The latter could be induced by numerous pathological conditions characterized by increased levels of free radicals and decreased levels of antioxidants. Pregnancy is a period when women undergo a physiological state of oxidative stress due to hormonal changes and increased oxygen requirements to maintain pregnancy. However, when oxidative stress exceeds antioxidant capacity, this leads to cellular damage that promotes a diabetogenic state. Recent studies suggest a possible association between gestational diabetes and cognitive impairment, but the underlying mechanisms remain unclear.

AIMS

We aim to explore the pathophysiological relationship between cognitive impairment and oxidative stress, focusing on the possible involvement of oxidative stress as the inducing mechanism.

METHODS

We performed a comprehensive literature review through PubMed and Google Scholar. Our keywords were "neuroinflammation", "cognitive impairment", "gestational diabetes", "oxidative stress", "antioxidants", and "free radicals".

RESULTS

From the initial 400 records identified, a total of 78 studies were analyzed and included in our study.

CONCLUSION

Oxidative stress plays a fundamental role in the development of cognitive impairment. Understanding this correlation is essential to the development of targeted medical interventions and, ultimately, promote research and prevention that will benefit the mother-child binomial in the short and long term.

CDDO, an Anti-Inflammatory and Antioxidant Compound, Attenuates Vasospasm and Neuronal Cell Apoptosis in Rats Subjected to Experimental Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a type of stroke caused by bleeding into the subarachnoid space. SAH is a medical emergency and requires prompt treatment to prevent complications such as seizures, stroke, or other brain damage. Treatment options may include surgery, medication, or a combination of both. 2-Cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO), a compound with anti-inflammatory and antioxidant properties, is currently being investigated as a potential treatment for various diseases, including chronic kidney disease and pulmonary arterial hypertension. In this study, the effects of CDDO on rats subjected to SAH were evaluated. Male Sprague-Dawley rats were divided into four groups (n = 6/group): (1) control group, (2) SAH group, (3) SAH + low-dose CDDO (10 mg/kg injected into the subarachnoid space at 24 h after SAH) group, and (4) SAH + high-dose CDDO (20 mg/kg) group. CDDO improved SAH-induced poor neurological outcomes and reduced vasospasm in the basal artery following SAH. It also decreased the SAH-induced expression of proinflammatory cytokines such as TNF-α, IL-1β, and IL-6 in both the cerebrospinal fluid and serum samples as determined by ELISA. A Western blot analysis confirmed an increase in the p-NF-κB protein level after SAH, but it was significantly decreased with CDDO intervention. Immunofluorescence staining highlighted the proliferation of microglia and astrocytes as well as apoptosis of the neuronal cells after SAH, and treatment with CDDO markedly reduced the proliferation of these glial cells and apoptosis of the neuronal cells. The early administration of CDDO after SAH may effectively mitigate neuronal apoptosis and vasospasm by suppressing inflammation.

Opportunities and Challenges of Soy Proteins with Different Processing Applications

Soybean meal (SBM) is a prevailing plant protein supplement in animal diets because of its nutritional value and availability. This review paper explores the significance of SBM and processed soy products, emphasizing their nutritional and bioactive components, such as isoflavones and soyasaponins. These compounds are known for their antioxidant and anti-inflammatory properties and are associated with a reduced prevalence of chronic diseases. However, the presence of antinutritional compounds in SBM presents a significant challenge. The paper evaluates various processing methods, including ethanol/acid wash, enzyme treatment, and fermentation, which are aimed at enhancing the nutritional value of soy products. It highlights the significance to maintain a balance between nutritional enhancement and the preservation of beneficial bioactive compounds, emphasizing the importance of different processing techniques to fully exploit the health benefits of soy-based products. Therefore, this review illuminates the complex balance between nutritional improvement, bioactive compound preservation, and the overall health implications of soy products.

Emerging regulatory mechanisms in cardiovascular disease: Ferroptosis

Ferroptosis, distinct from apoptosis, necrosis, autophagy, and other types of cell death, is a novel iron-dependent regulated cell death characterized by the accumulation of lipid peroxides and redox imbalance with distinct morphological, biochemical, and genetic features. Dysregulation of iron homeostasis, the disruption of antioxidative stress pathways and lipid peroxidation are crucial in ferroptosis. Ferroptosis is involved in the pathogenesis of several cardiovascular diseases, including atherosclerosis, cardiomyopathy, myocardial infarction, ischemia-reperfusion injury, abdominal aortic aneurysm, aortic dissection, and heart failure. Therefore, a comprehensive understanding of the mechanisms that regulate ferroptosis in cardiovascular diseases will enhance the prevention and treatment of these diseases. This review discusses the latest findings on the molecular mechanisms of ferroptosis and its regulation in cardiovascular diseases, the application of ferroptosis modulators in cardiovascular diseases, and the role of traditional Chinese medicines in ferroptosis regulation to provide a comprehensive understanding of the pathogenesis of cardiovascular diseases and identify new prevention and treatment options.

LncRNA CARMN inhibits abdominal aortic aneurysm formation and vascular smooth muscle cell phenotypic transformation by interacting with SRF

Phenotypic transformation of vascular smooth muscle cells (VSMCs) plays a crucial role in abdominal aortic aneurysm (AAA) formation. CARMN, a highly conserved, VSMC-enriched long noncoding RNA (lncRNA), is integral in orchestrating various vascular pathologies by modulating the phenotypic dynamics of VSMCs. The influence of CARMN on AAA formation, particularly its mechanisms, remains enigmatic. Our research, employing single-cell and bulk RNA sequencing, has uncovered a significant suppression of CARMN in AAA specimens, which correlates strongly with the contractile function of VSMCs. This reduced expression of CARMN was consistent in both 7- and 14-day porcine pancreatic elastase (PPE)-induced mouse models of AAA and in human clinical cases. Functional analyses disclosed that the diminution of CARMN exacerbated PPE-precipitated AAA formation, whereas its augmentation conferred protection against such formation. Mechanistically, we found CARMN's capacity to bind with SRF, thereby amplifying its role in driving the transcription of VSMC marker genes. In addition, our findings indicate an enhancement in CAMRN transcription, facilitated by the binding of NRF2 to its promoter region. Our study indicated that CARMN plays a protective role in preventing AAA formation and restrains the phenotypic transformation of VSMC through its interaction with SRF. Additionally, we observed that the expression of CARMN is augmented by NRF2 binding to its promoter region. These findings suggest the potential of CARMN as a viable therapeutic target in the treatment of AAA.

Nrf2 activator Diethyl Maleate attenuates ROS mediated NLRP3 inflammasome activation in murine microglia

Microglia are the tissue-resident immune cells of the central nervous system. As a part of the innate immune response, NLR Family Pyrin Domain Containing Protein 3 (NLRP3) inflammasome activation leads to cleavage of caspase-1 and triggers secretion of proinflammatory cytokines and may also result in pyroptotic cell death. Inflammasome activation plays a crucial role in inflammatory conditions; aberrant activation of inflammasome contributes to the pathogenesis of neurodegenerative diseases. Diethyl Maleate (DEM) is a promising antiinflammatory chemical to alleviate inflammasome activation. In this study, NLRP3 inflammasome was activated in N9 murine microglia via 1 µg/ml LPS (Lipopolysaccharide) for 4 h and 5 mM ATP (Adenosine 5'-triphosphate) for 1 h, respectively. We demonstrated that 1 h pretreatment of DEM attenuated NLRP3 inflammasome activation in microglial cells. Besides, mitochondrial ROS decreased upon DEM pretreatment in inflammasome-induced cells. Likewise, it ameliorated pyroptotic cell death in microglia. DEM is a potent activator of Nrf2 transcription factor, the key regulator of the antioxidant response pathway. Nrf2 has been a significant target to decrease aberrant inflammasome activation through the antioxidant compounds, including DEM. Here, we have shown that DEM increased Nrf2 translocation to the nucleus, resulting in Nrf2 target gene expression in microglia. In conclusion, DEM is a promising protective agent against NLRP3 inflammasome activation.

Ferroptosis regulation through Nrf2 and implications for neurodegenerative diseases

This article provides an overview of the background knowledge of ferroptosis in the nervous system, as well as the key role of nuclear factor E2-related factor 2 (Nrf2) in regulating ferroptosis. The article takes Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS) as the starting point to explore the close association between Nrf2 and ferroptosis, which is of clear and significant importance for understanding the mechanism of neurodegenerative diseases (NDs) based on oxidative stress (OS). Accumulating evidence links ferroptosis to the pathogenesis of NDs. As the disease progresses, damage to the antioxidant system, excessive OS, and altered Nrf2 expression levels, especially the inhibition of ferroptosis by lipid peroxidation inhibitors and adaptive enhancement of Nrf2 signaling, demonstrate the potential clinical significance of Nrf2 in detecting and identifying ferroptosis, as well as targeted therapy for neuronal loss and mitochondrial dysfunction. These findings provide new insights and possibilities for the treatment and prevention of NDs.