Toward clinical application of the Keap1-Nrf2 pathway

Silencing NRF2 enhances arsenic trioxide-induced ferroptosis in hepatocellular carcinoma cells

OBJECTIVE

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths worldwide, with high mortality rates partially due to limited therapeutic options and drug resistance. Arsenic trioxide (ATO), a compound clinically proven for acute promyelocytic leukemia (APL), has garnered attention for its emerging efficacy in solid tumors, including HCC. However, the molecular mechanisms driving ATO's antitumor activity in HCC remain incompletely understood. In this study, we aimed to elucidate the ferroptosis-dependent effects of ATO on HCC and and propose a potential therapeutic strategy.

METHODS

The response of HCC cells to ATO was evaluated using cell viability, wound healing, colony formation, Transwell migration assays, and cell cycle analysis. ATO-induced ferroptosis was assessed by measuring lipid peroxidation (via C11-BODIPY staining), intracellular iron levels, and malondialdehyde (MDA) production. Western blotting was performed to quantify protein levels of NRF2, HO-1, SLC7A11, and GPX4; immunofluorescence staining was employed to determine NRF2 subcellular localization.

RESULTS

ATO exhibited significant cytotoxicity and inhibited the progression of HCC cells. Treatment with ATO resulted in a notable increase in lipid ROS and MDA levels, which were subsequently reversed by the ferroptosis inhibitors Fer-1 and DFO. Mechanistically, ATO induced ferroptosis by inhibiting GPX4. Furthermore, NRF2 and its downstream targets, HO-1 and SLC7A11, were upregulated during ferroptosis. NRF2 knockdown enhanced lipid peroxidation and ATO-induced cell death.

CONCLUSIONS

ATO significantly promoted ferroptosis in HCC cells, and NRF2 knockdown enhanced the cytotoxic effects of ATO.

Bixin alleviates radiation-induced intestinal damage via inflammation regulation and barrier recovery

PURPOSE

Radiotherapy for cancer treatment or unintentional exposure to ionizing radiation causes severe damage to the unaffected tissues of the digestive system, including gastrointestinal (GI) tract. Radiation exposure leads to an inflammatory response, and uncontrolled inflammation exacerbates radiation-induced tissue injury. Bixin is a liposoluble apocarotenoid isolated from Bixa orrellana seeds, which effectively attenuates several inflammatory diseases. In this study, we investigated whether bixin mitigated radiation-induced intestinal damage through an examination of its role in inflammation and the protection of the epithelial barrier.

MATERIALS AND METHODS

To determine the therapeutic effects of bixin in treating radiation-induced intestinal damage, we carried out histological analyses, inflammatory response examinations, and barrier function assessments using a mouse model of radiation-induced enteropathy.

RESULTS

We uncovered that bixin effectively mitigates radiation-induced enteropathy by suppressing the inflammatory response, reducing inflammatory cell accumulation, and limiting cytokine expression in the radiation-induced intestinal injury. In a mouse model of acute radiation-induced intestinal injury, treatment with bixin enhanced nuclear factor erythroid-2-related factor 2 (NRF2) activation and promoted tight junction expression in the epithelium, while also hindering bacterial translocation to the mesenteric lymph nodes.

CONCLUSION

Bixin represents a potential therapeutic candidate for the treatment of radiation-induced enteropathy.

Lactiplantibacillus plantarum -derived extracellular vesicles alleviate acute lung injury by inhibiting ferroptosis of macrophages

Despite considerable advancements in understanding the mechanisms of ALI, the therapeutic options available in clinical practice remain predominantly supportive, highlighting the urgent need for innovative treatments. In this study, we investigated the potential protective benefits of extracellular vehicles from the probiotic strain Lactiplantibacillus plantarum (LpEVs) in ALI mouse model. We revealed that LpEVs administration attenuated LPS-induced ALI, as evidenced by reduced lung pathology, decreased inflammatory markers, and mitigated ferroptosis. In vitro experiments demonstrated that LpEVs restrained ferroptosis and promoted a shift towards an anti-inflammatory macrophage phenotype. Moreover, LpEVs increased the expression of NRF2, resulting in the promotion of HO1 and strengthening anti-ferroptotic System Xc-/GPX4 axis. Our analysis revealed that LpEVs alleviated ALI through the suppression of macrophages ferroptosis by delivering cbn-let-7 targeting ferroptosis-related gene Acsl4. These findings propose LpEVs as a promising therapeutic approach for preventing and treating ALI, highlighting the potential of leveraging probiotic-derived biomolecules to develop novel therapeutic strategies.

Enhancing spermatogonial stem cell differentiation: The role of alpha-ketoglutarate in in-Vitro cultures

Spermatogonial stem cells (SSCs) have the unique ability to self-renew and differentiate into mature spermatozoa. In vitro culture of SSCs, however, presents several challenges, particularly in promoting efficient differentiation. This study investigates the role of metabolic intermediates, such as alpha-ketoglutarate (AKG), on the differentiation of SSCs isolated from the testes of 3-6 day-old mice. SSCs and sertoli cells were extracted using collagenase ІV and trypsin and co-cultured in DMEM/F12 supplemented with 20 % fetal bovine serum (FBS) and glial cell-derived neurotrophic factor (GDNF) for one week. The survival rate of cells was evaluated under influence of different dosages of AKG (0.04, 0.1, 0.4, 4, 10 mM) after 1 and 7 days of culture using the MTT test. The cell viability was significantly increased at the 0.1 mM dose of AKG rather than other groups. This dosage was selected for adding to culture system. In the control group, the cells cultured for three weeks in DMEM/F12 with 10 % FBS, 10⁻6 M retinoic acid, and 40 ng/mL bone morphogenetic protein-4 (BMP-4). The treatment group received the same medium with the addition of 0.1 mM AKG. The presence of Sertoli cell in the culture system was confirmed by SOX9-positive immunocytochemistry. The Colonies that formed on the Sertoli cells exhibited positive alkaline phosphatase activity and reacted positively for Oct4 and GFRa1 immunocytochemistry. The expression of testicular-specific genes (Acrosin and Sycp3) and anti-apoptosis-related genes (Nrf2 and Bcl2) was evaluated after 7 days (as the zero group) and again after 21 days of culture, in treatment (0.1 mM AKG) and control groups. A high expression of Acrosin and Sycp3 expression was observed in AKG-treated group compared to control and zero groups (p ≤ 0.05). The expression of Nrf2 and Bcl2 genes was also significantly increased in the treatment group (p ≤ 0.05). These findings suggest that AKG activates mechanisms of cellular antioxidant response and subsequently increase the expression of differentiation genes in SSCs.

Porcine reproductive and respiratory syndrome virus nsp5 inhibits the activation of the Nrf2/HO-1 pathway by targeting p62 to antagonize its antiviral activity

Porcine reproductive and respiratory syndrome virus (PRRSV) infections often trigger oxidative stress and cytokine storms, resulting in significant tissue damage that causes fatalities in piglets and reproductive issues in sows. However, it is still unknown how oxidative stress is regulated by viral and host factors in response to PRRSV infection. Here, we found that PRRSV induced cellular oxidative stress by triggering the production of reactive oxygen species and inhibiting the expression of antioxidant enzymes. Although Nrf2 is an important redox regulator that initiates the expression of downstream antioxidant genes, PRRSV can impair the Nrf2/HO-1 pathway. The overexpression of Nrf2 showed a significant anti-PRRSV effect, and inhibiting the expression of Nrf2 promoted the proliferation of PRRSV. Further analysis showed that Nrf2 positively regulated the production of type I interferons and interferon-stimulated genes, which may contribute to its anti-PRRSV effect. By screening the PRRSV-encoded protein, we found that the PRRSV nsp5 protein can degrade Nrf2 at the protein level. Mechanistically, nsp5 promotes Nrf2-Keap1 binding affinity by inhibiting p62-mediated Keap1 sequestration and increasing Keap1 expression. Subsequently, this increased Keap1-mediated degradation of Nrf2 ubiquitination through K48-linked polyubiquitin. Furthermore, we found that the residues Tyr146 and Arg147 of nsp5 are crucial for inhibiting the activation of the p62-mediated Nrf2 antioxidant pathway. Thus, our findings uncover a novel mechanism by which PRRSV disrupts the host antioxidant defense system and highlight the crucial role of the Nrf2/HO-1 antioxidant pathway in host defense against PRRSV.IMPORTANCEOxidative stress-induced redox imbalance is a crucial pathogenic mechanism in viral infections. Nrf2 and its antioxidant genes serve as the main defense pathways against oxidative stress. However, the role of Nrf2 in the context of porcine reproductive and respiratory syndrome virus (PRRSV) infection remains unclear. In this study, we demonstrated that PRRSV infection decreased the expression of antioxidant genes of the Nrf2 signaling pathway and overexpression of Nrf2 triggered a strong anti-PRRSV effect. PRRSV nsp5 enhanced Keap1-dependent degradation of Nrf2 ubiquitination, thereby weakening cellular resistance to oxidative stress and antagonizing the antiviral activity of Nrf2. Our study further revealed a new mechanism by which PRRSV evades host antiviral innate immunity by disturbing cellular redox homeostasis, providing a new target for developing anti-PRRSV drugs.

Effects of sulforaphane on negative symptoms and cognitive impairments in chronic schizophrenia patients: A randomized double-blind trial

BACKGROUND

The pathological mechanisms of negative symptoms and cognitive impairment in schizophrenia may involve oxidative stress and neuroinflammation. Sulforaphane is an organosulfur compound with antioxidant and anti-inflammatory properties. This study aimed to evaluate its efficacy in ameliorating negative symptoms and cognitive impairments in chronic schizophrenia patients.

METHOD

This 24-week double-blind randomised trial (NCT04521868) recruited schizophrenia patients with significant negative symptoms. Participants were randomly assigned to receive either sulforaphane or placebo and were required to complete at least one post-intervention assessment to evaluate changes in negative symptoms and cognitive functioning. Existing antipsychotic medication treatment regimens remained unchanged throughout the study.

RESULTS

A total of 42 patients were included in the statistical analysis, with 28 receiving sulforaphane and 14 assigned to placebo. Sulforaphane significantly reduced the Negative Symptom Score from the PANSS 5-Factor model between groups (p = 0.007) and exhibited a significant time-by-group interaction (p = 0.023), with more pronounced group differences observed after 12 weeks compared to 24 weeks of treatment. Sulforaphane also demonstrated a significant reduction in the original PANSS Negative Symptom Score between groups (p = 0.029). However, sulforaphane showed no significant effects on the MATRICS Consensus Cognitive Battery composite score or its subscores.

CONCLUSION

The significant improvements in the Negative Symptom Score from the PANSS 5-Factor model and the original PANSS Negative Symptom Score in the sulforaphane group suggest the potential of sulforaphane as an adjunctive treatment for ameliorating negative symptoms in chronic schizophrenia. Further research is warranted to explore the effects of sulforaphane on cognitive function.

Growth Arrest-specific 1 Inhibits Keap1/Nrf2 Signaling Transduction in the Activation of the Ferroptosis Program in Retinal Müller Cells

BACKGROUND

Diabetes retinopathy (DR) represents a microvascular disease in diabetes. Growth arrest-specific 1 (GAS1) is differentially expressed in rat retinal Müller cells under high glucose (HG) conditions, and its promotion of ferroptosis contributes to retinal cell death. However, the influence of GAS1 in DR is elusive. Herein, we aimed to investigate the effect and potential mechanism based on GAS1-mediated ferroptosis on DR.

METHODS

After HG treatment, the differentially expressed genes in rat retinal Müller cells were analyzed by transcriptome sequencing followed by Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses; finally, GAS1 was selected. The effects of GAS1 knockdown/overexpression and nuclear factor erythroid 2-related factor (Nrf2) silencing on viability, apoptosis, lipid peroxidation, Fe2+, and oxidative stress levels in HG-induced/transfected Müller cells were measured by Cell Counting Kit-8 (CCK-8) assay, flow cytometry, and commercial reagent kits. The potential effects of GAS1 and Nrf2, especially on GAS1, Nrf2, and Kelch-like ECH-associated protein 1 (Keap1) expressions in cells, were determined by quantitative real-time polymerase chain reaction (qRT-PCR) or Western blot.

RESULTS

HG treatment decreased cell viability and glutathione (GSH) levels and increased apoptosis, lipid reactive oxygen species (ROS), glutathione disulfide (GSSG), malondialdehyde (MDA), oxidative stress, and Fe2+ levels in Müller cells (p < 0.01). HG treatment also upregulated GAS1, Keap1, and total Nrf2 expressions while downregulating nuclear Nrf2 in Müller cells (p < 0.001). GAS1 downregulation enhanced cell viability, GSH levels, and nuclear Nrf2 expression while reducing the levels of apoptosis, lipid ROS, GSSG, MDA, Fe2+, Keap1, and total Nrf2 in HG-treated Müller cells (p < 0.001), whereas GAS1 overexpression had the opposite effects. Additionally, Nrf2 silencing reversed the impact of GAS1 overexpression in HG-treated Müller cells (p < 0.05).

CONCLUSION

GAS1 inhibits Keap1/Nrf2 signaling transduction in activating ferroptosis in retinal Müller cells; thus, this study can aid in setting the stage for novel treatment methods against DR.

Nodule-Specific NRF2-Targeted Upregulation in Patients With KEAP1 Mutations and Familial Nontoxic Multinodular Goiter

CONTEXT

Kelch-like ECH-associated protein 1 (KEAP1) is associated with nuclear factor erythroid-2-related factor 2 (NRF2) and promotes NRF2 degradation in normal conditions. Genetic abnormality in KEAP1 is a rare disease and presents with familial multinodular goiter.

OBJECTIVE

This study assessed the clinical and molecular findings concerning nodular formation in the thyroid gland of patients harboring KEAP1 germline mutations.

METHODS

Next-generation sequencing analysis targeting goiter-associated genes was performed on 39 patients with familial multinodular goiter. The expression of NRF2-targeted genes from surgical thyroid specimens of patients with KEAP1 mutations were analyzed using a whole-transcript expression array and immunohistochemistry.

RESULTS

We found 5 probands with pathogenic heterozygous mutations in KEAP1 (p.Q86*, p.L136P, p.V411fs, p.R415C, and p.R483H) that had no meaningful concomitance with mutations of other goiter-associated genes at germline and somatic levels. Their common histopathological features showed multinodular goiters in the entire thyroid gland with few degenerative lesions or complications of malignancy and slow proliferation indicating less than 1% at the Ki-67 labeling index. Among 42 NRF2-targeted genes, antioxidant genes were most frequently upregulated (11/12) in the nodule, followed by detoxification genes (6/11). Immunohistochemical analysis showed relatively high expression of glutathione peroxidase 2 and NAD(P)H quinone oxidoreductase 1 (representative NRF2-targeted genes) in the nodules of various patients harboring KEAP1 mutations.

CONCLUSION

KEAP1 germline heterozygous mutations exert excessive NRF2 activity in the thyroid gland and may confer cytoprotective effects even under abundant reactive oxygen species associated with thyroid hormone production, resulting in thyroid hyperplasia with scarce degradation.

Selenoprotein-mediated redox regulation shapes the cell fate of HSCs and mature lineages

ABSTRACT

The maintenance of cellular redox balance is crucial for cell survival and homeostasis and is disrupted with aging. Selenoproteins, comprising essential antioxidant enzymes, raise intriguing questions about their involvement in hematopoietic aging and potential reversibility. Motivated by our observation of messenger RNA downregulation of key antioxidant selenoproteins in aged human hematopoietic stem cells (HSCs) and previous findings of increased lipid peroxidation in aged hematopoiesis, we used selenocysteine transfer RNA (tRNASec) gene (Trsp) knockout (KO) mouse model to simulate disrupted selenoprotein synthesis. This revealed insights into the protective roles of selenoproteins in preserving HSC stemness and B-lineage maturation, despite negligible effects on myeloid cells. Notably, Trsp KO exhibited B lymphocytopenia and reduced HSCs' self-renewal capacity, recapitulating certain aspects of aged phenotypes, along with the upregulation of aging-related genes in both HSCs and pre-B cells. Although Trsp KO activated an antioxidant response transcription factor NRF2, we delineated a lineage-dependent phenotype driven by lipid peroxidation, which was exacerbated with aging yet ameliorated by ferroptosis inhibitors such as vitamin E. Interestingly, the myeloid genes were ectopically expressed in pre-B cells of Trsp KO mice, and KO pro-B/pre-B cells displayed differentiation potential toward functional CD11b+ fraction in the transplant model, suggesting that disrupted selenoprotein synthesis induces the potential of B-to-myeloid switch. Given the similarities between the KO model and aged wild-type mice, including ferroptosis vulnerability, impaired HSC self-renewal and B-lineage maturation, and characteristic lineage switch, our findings underscore the critical role of selenoprotein-mediated redox regulation in maintaining balanced hematopoiesis and suggest the preventive potential of selenoproteins against aging-related alterations.

Intratumour oxidative hotspots provide a niche for cancer cell dissemination

Intratumour heterogeneity represents the hierarchical integration of genetic, phenotypic and microenvironmental heterogeneity. Although single-cell sequencing has clarified genetic and phenotypic variability, the heterogeneity of nongenetic, microenvironmental factors remains elusive. Here, we developed T-AP1, a tumour-targeted probe tracking extracellular H2O2, which allows the visualization and characterization of tumour cells exposed to oxidative stress, a hallmark of cancer. T-AP1 identified actively budding intratumour regions as H2O2-rich microenvironments (H2O2 hotspots), which were primarily established by neutrophils. Mechanistically, tumour cells exposed to H2O2 underwent partial epithelial-mesenchymal transition through p38-MYC axis activation and migrated away from H2O2 hotspots. This escape mechanism was absent in normal epithelial cells but prevalent in most cancers except NRF2-hyperactivated tumours, which exhibited abrogated p38 responses and enhanced antioxidant programmes, thus revealing an intrinsic stress defence programme in cancers. Together, T-AP1 enabled the identification of H2O2 hotspots that provide a niche for cancer cell dissemination, offering insights into metastasis initiation.

Hsa-miR-532-3p protects human decidual mesenchymal stem cells from oxidative stress in recurrent spontaneous abortion via targeting KEAP1

BACKGROUND

Human decidual mesenchymal stem cells (hDMSCs) play crucial roles in pregnancy. The decreased resistance of hDMSCs to oxidative stress is a key factor contributing to recurrent spontaneous abortion (RSA). miRNAs have essential functions in the proliferation and apoptosis of decidual tissues. However, the miRNAs involved in regulating oxidative stress in hDMSCs remain unclear.

METHODS

Decidual tissues and hDMSCs were collected from patients with RSA and early pregnancy miscarriages. We assessed the antioxidant capacity of hDMSCs in both groups by detecting relevant indicators. Furthermore, differentially expressed miRNAs in hDMSCs were analyzed through miRNA sequencing. We evaluated the interaction between hsa-miR-532-3p and KEAP1 using a luciferase reporter assay. A mouse model of RSA was constructed for confirmation. Finally, we analyzed the correlations between serum hsa-miR-532-3p levels and the clinical features of pregnant women with RSA.

RESULTS

miRNA sequencing revealed 44 miRNAs whose expression was downregulated and 9 miRNAs whose expression was upregulated in hDMSCs from the RSA group compared with those from the control group. The overexpression of hsa-miR-532-3p led to a significantly increased antioxidant capacity in hDMSCs. The knockdown or overexpression of hsa-miR-532-3p led to the upregulation or downregulation of KEAP1 expression, respectively. In a mouse model, the overexpression of hsa-miR-532-3p reduced embryo absorption rates in RSA mice, decreased KEAP1 expression levels in decidual tissues, and concurrently enhanced the resistance to oxidative stress. Furthermore, in patients diagnosed with RSA, serum hsa-miR-532-3p levels were significantly and negatively correlated with the gestational age.

CONCLUSIONS

Our study revealed a lower expression level of hsa-miR-532-3p in the hDMSCs of patients with RSA. Moreover, hsa-miR-532-3p protects hDMSCs from oxidative stress by targeting the Kelch-like ECH-associated protein 1/nuclear factor erythroid 2-related factor 2 (KEAP1/NRF2) pathway. Hsa-miR-532-3p is closely related to gestational age and has good predictive value for identifying RSA.

A novel KEAP1 inhibitor, tiliroside, activates NRF2 to protect against acetaminophen-induced oxidative stress and acute liver injury

BACKGROUND

Acetaminophen-induced acute liver injury (AILI) is one of the common causes of abrupt liver failure in numerous nations. Several previous studies revealed that tiliroside, a glycoside flavonoid, exerts neuroprotective and renal protective effects. However, whether it has hepatoprotective effects is not known. The objective of this research is to examine whether tiliroside can protect against AILI.

METHODS

AILI mouse and cell models were performed to evaluate the protective effects of tiliroside. Molecular docking, cellular thermal shift assay, immunoprecipitation, and RNA-seq were performed to analyze the possible mechanisms of tiliroside.

RESULTS

In vivo, tiliroside attenuated AILI in mice significantly, as evidenced by lower ALT and AST levels. Molecular docking, cellular thermal shift assay, and RNA-seq analysis revealed that tiliroside promoted the activation of nuclear factor erythroid 2-related factor 2 (NRF2) and the expression of its downstream genes through disruption of the NRF2-KEAP1 protein-protein interaction to inhibit KEAP1-mediated ubiquitination and degradation of NRF2, thereby inhibiting oxidative stress in the livers of AILI mice. Furthermore, hepatocyte-specific knockout of NRF2 greatly attenuated the hepatic-protective effects of tiliroside in mice. In vitro, tiliroside protected against acetaminophen-induced oxidative stress on cultured hepatocytes through activation of NRF2. In addition, NRF2 knockout markedly blunted the protection effects of tiliroside, suggesting that NRF2 mediates the hepatic-protective effects of tiliroside.

CONCLUSIONS

Our study demonstrated that tiliroside could protect against AILI by activating the KEAP1/NRF2 pathway, which primarily inhibits the processing of oxidative stress and cell death. Our results suggest that tiliroside could serve as a potential agent for the clinical treatment of AILI.

The beneficial effects of curcumin on aging and age-related diseases: from oxidative stress to antioxidant mechanisms, brain health and apoptosis

Aging and age-related disease are among the most common and challenging issues worldwide. During the aging process, the accumulation of oxidative stress, DNA damage, telomere dysfunction, and other related changes lead to cellular dysfunction and the development of diseases such as neurodegenerative and cardiovascular conditions. Curcumin is a widely-used dietary supplement against various diseases such as cancer, diabetes, cardiovascular diseases and aging. This agent mediates its effects through several mechanisms, including the reduction of reactive oxygen species (ROS) and oxidative stress-induced damage, as well as the modulation of subcellular signaling pathways such as AMPK, AKT/mTOR, and NF-κB. These pathways are involved in cellular senescence and inflammation, and their modulation can improve cell function and help prevent disease. In cancer, Curcumin can induce apoptosis in a variety of different tumor cell lines. Curcumin also activates redox reactions within cells inducing ROS production that leads to the upregulation of apoptosis receptors on the tumor cell membrane. Curcumin can also upregulate the expression and activity of p53 that inhibits tumor cell proliferation and increases apoptosis. Furthermore, curcumin has a potent inhibitory effect on the activity of nuclear factor kappa B (NF-κB) and cyclooxygenase-2 (COX-2), which are involved in the overexpression of antiapoptosis genes such as Bcl-2. It can also attenuate the regulation of antiapoptosis phosphoinositide 3-kinases (PI3K) signaling and increase the expression of mitogen-activated protein kinases (MAPKs) to induce endogenous production of ROS. Therefore, herein, we aim to summarize how curcumin affect different epigenetic processes (such as apoptosis and oxidative stress) in order to change aging-related mechanisms. Furthermore, we discuss its roles in age-related diseases, such as Alzheimer, Parkinson, osteoporosis, and cardiovascular diseases.

Lactobacillus acidophilus alleviate Salmonella enterica Serovar Typhimurium-induced murine inflammatory/oxidative responses via the p62-Keap1-Nrf2 signaling pathway and cecal microbiota

Background

Salmonella enterica Serovar Typhimurium (S. Typhimurium) infection can cause inflammation and oxidative stress in the body, leading to gastroenteritis, fever and other diseases in humans and animals. More and more studies have emphasized the broad prospects of probiotics in improving inflammation and oxidative stress, but the ability and mechanism of Lactobacillus acidophilus (LA) to alleviate the inflammatory/oxidative reaction caused by pathogens are still unclear.

Methods and results

In this study, we treated the mice with LA for 14 days, infected them with S. Typhimurium for 24 h, and sacrificed the mice to collect samples. We found that the early intervention of LA alleviated the pathological injury and reversed the down-regulation of the duodenal and hepatic tight junction protein mRNA levels caused by S. Typhimurium infection. Compared with S. Typhimurium group, LA early intervention increased the expression of antioxidant enzymes, but decreased the levels of serum malondialdehyde (MDA), interleukin-8 and tumor necrosis factor-α (TNF-α). Additionally, LA early intervention significantly increased Nrf2 mRNA expression in the liver and decreased Keap1 mRNA expression in the duodenum compared to the S. Typhimurium group. Furthermore, early LA treatment reduced the abundance of Bacteroides acidificiens, increased the abundance of Akkermansia, and alleviated the decrease in SCFAs levels in the cecum of S. Typhimurium-infected mice. Spearman correlation analysis showed that there was a certain correlation between cecal flora and serum indicators and short chain fatty acids.

Conclusion

Taken together, the results indicate that LA early intervention may alleviates S. Typhimurium-induced inflammation and oxidative responses in mice by activating the p62-Keap1-Nrf2 signaling pathway and regulating the gut microbial community.

Significance and impact of the study

Exploring the ability of LA to resist animal oxidative stress and microflora regulation caused by pathogenic microbes, so as to provide more options for developing healthy disease-resistant feed additives.

The SIRT-1/Nrf2/HO-1 axis: Guardians of neuronal health in neurological disorders

SIRT1 (Sirtuin 1) is a NAD+-dependent deacetylase that functions through nucleoplasmic transfer and is present in nearly all mammalian tissues. SIRT1 is believed to deacetylate its protein substrates, resulting in neuroprotective actions, including reduced oxidative stress and inflammation, increased autophagy, increased nerve growth factors, and preserved neuronal integrity in aging or neurological disease. Nrf2 is a transcription factor that regulates the genes responsible for oxidative stress response and substance detoxification. The activation of Nrf2 guards cells against oxidative damage, inflammation, and carcinogenic stimuli. Several neurological abnormalities and inflammatory disorders have been associated with variations in Nrf2 activation caused by either pharmacological or genetic factors. Recent evidence indicates that Nrf2 is at the center of a complex cellular regulatory network, establishing it as a transcription factor with genuine pleiotropy. HO-1 is most likely a component of a defense mechanism in cells under stress, as it provides negative feedback for cell activation and mediator synthesis. This mediator is upregulated by Nrf2, nitric oxide (NO), and other factors in various inflammatory states. HO-1 or its metabolites, such as CO, may mitigate inflammation by modulating signal transduction pathways. Neurological diseases may be effectively treated by modulating the activity of HO-1. Multiple studies have demonstrated that SIRT1 and Nrf2 share an important connection. SIRT1 enhances Nrf2, activates HO-1, protects against oxidative injury, and decreases neuronal death. This has been associated with numerous neurodegenerative and neuropsychiatric disorders. Therefore, activating the SIRT1/Nrf2/HO-1 pathway may help treat various neurological disorders. This review focuses on the current understanding of the SIRT1 and Nrf2/HO-1 neuroprotective processes and the potential therapeutic applications of their target activators in neurodegenerative and neuropsychiatric disorders.

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.

Neuroprotective role of CHCHD2 in Parkinson's disease: Insights into the GPX4-related ferroptosis pathway

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease, characterized by pathogenesis involving mitochondrial dysfunction, oxidative stress, and ferroptosis. Unfortunately, there are currently no effective interventions to slow down the progression of PD. The mitochondrial protein coiled-coil-helix-coiled-coil-helix domain containing 2 (CHCHD2), which is implicated in neurodegeneration and serves as a biomarker for PD, has been reported to have neuroprotective effects against oxidative stress, but the potential molecular mechanisms involved remain elusive. In this study, we uncovered a critical mechanism by which CHCHD2 protected neuronal cells against oxidative stress with the ferroptosis pathway playing a pivotal role, as determined through tandem mass tags (TMT)-based proteomic analysis. The overexpression of CHCHD2 was observed to enhance cell viability, reduce levels of lipid peroxidation and reactive oxygen species (ROS), and upregulate the expression of the ferroptosis negative regulatory protein Glutathione peroxidase 4 (GPX4) in PD cells. Conversely, CHCHD2 knockdown led to reduced cell viability, elevated lipid peroxidation, and a decreased expression of GPX4. Additionally, CHCHD2 overexpression ameliorated motor function impairment, reduced α-synuclein levels, and mitigated dopaminergic (DA) neuron loss in the substantia nigra and striatum of PD mice. Importantly, we show that the inhibitory effect of CHCHD2 on ferroptosis in PD is related to the GPX4 signaling pathway. In summary, our study elucidates the neuroprotective role of CHCHD2 in regulating the GPX4-related ferroptosis pathway in PD, providing new targets and ideas for future PD drug development and therapy.

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.

JP4-039 Mitigates Cisplatin-Induced Acute Kidney Injury by Inhibiting Oxidative Stress and Blocking Apoptosis and Ferroptosis in Mice

Cisplatin is a commonly used chemotherapeutic agent in the treatment of a wide array of cancers. Due to its active transport into the kidney proximal tubule cells, cisplatin treatment can cause a buildup of this nephrotoxic compound in the kidney, resulting in acute kidney injury (AKI). About 30% of patients receiving cisplatin chemotherapy develop cisplatin-induced AKI. JP4-039 is a mitochondria-targeted reactive oxygen species (ROS) and electron scavenger. Recent studies have shown that JP4-039 mitigates a variety of genotoxic insults in preclinical studies in rodents by suppressing oxidative stress-mediated tissue damage and blocking apoptosis and ferroptosis. However, the benefits of JP4-039 treatment have not been tested in the setting of AKI. In this study, we investigated the potential renoprotective effect of JP4-039 on cisplatin-induced AKI. To address this goal, we treated mice with JP4-039 before or after cisplatin administration and analyzed them for functional and molecular changes in the kidney. JP4-039 co-administration attenuated cisplatin-induced renal dysfunction and histopathological changes. Upregulation of tubular injury markers was also suppressed by JP4-039. Mechanistically, JP4-039 suppressed lipid peroxidation, prevented tissue oxidative stress, and preserved the glutathione levels in cisplatin-injected mice. An increase in cisplatin-induced apoptosis and ferroptosis was also alleviated by the compound. Moreover, JP4-039 inhibited cytokine overproduction in cisplatin-injected mice. Together, our findings demonstrate that JP4-039 is a promising therapeutic agent against cisplatin-induced kidney injury.

Interplay between epigenetics, senescence and cellular redox metabolism in cancer and its therapeutic implications

There is accumulating evidence indicating a close crosstalk between key molecular events regulating cell growth and proliferation, which could profoundly impact carcinogenesis and its progression. Here we focus on reviewing observations highlighting the interplay between epigenetic modifications, irreversible cell cycle arrest or senescence, and cellular redox metabolism. Epigenetic alterations, such as DNA methylation and histone modifications, dynamically influence tumour transcriptome, thereby impacting tumour phenotype, survival, growth and spread. Interestingly, the acquisition of senescent phenotype can be triggered by epigenetic changes, acting as a double-edged sword via its ability to suppress tumorigenesis or by facilitating an inflammatory milieu conducive for cancer progression. Concurrently, an aberrant redox metabolism, which is a function of the balance between reactive oxygen species (ROS) generation and intracellular anti-oxidant defences, influences signalling cascades and genomic stability in cancer cells by serving as a critical link between epigenetics and senescence. Recognizing this intricate interconnection offers a nuanced perspective for therapeutic intervention by simultaneously targeting specific epigenetic modifications, modulating senescence dynamics, and restoring redox homeostasis.

Antioxidant peptides from silver carp steak by alkaline protease and flavor enzyme hydrolysis: Characterization of their structure and cytoprotective effects against H2O2-induced oxidative stress

Silver carp steak is a rarely utilized silver carp processing byproduct. This study aimed to optimize a dual enzymatic method to extract antioxidant peptide components from silver carp steak and characterize their structure and in vitro antioxidant activity through ultrafiltration purification, response surface methodology, molecular docking, and radical scavenging activity analysis. The optimal extraction conditions for silver carp steak antioxidant peptides (SCSAP) were determined as 1:6 solid-liquid ratio, 1500 U/g alkaline protease addition, 4 h alkaline protease hydrolysis time, 1946 U/g flavor enzyme addition, and 2.5 h flavor enzyme hydrolysis time. The <3 kDa SCSAP component (SCSAP-3kDa) showed the strongest antioxidant activity, with its 1,1-diphenyl-2-trinitrophenyl hydrazine (DPPH) radical scavenging rate, ABTS radical scavenging rate, hydroxyl radical scavenging rate, metal ion chelating rate, and reducing capacity reaching 88.75%, 91.21%, 67.02%, 69.07%, and 0.985, respectively. Moreover, the three peptides (PF-7, GP-8, and YF-10) of 100 µg/mL could protect HepG2 cells from oxidative stress damage by reducing the oxidative damage level and activating Keap1-Nrf2-ARE pathways, enabling an increase of superoxide dismutases (SOD) activity, and a decrease of malondialdehyde (MDA) content and reactive oxygen species (ROS) level. The integrated results indicate the enormous potential of SCSAP-3kDa as a functional food ingredient in the food industry. PRACTICAL APPLICATION: This study selected the antioxidant capacity of silver carp steak peptides as the index and developed a facile dual enzymatic hydrolysis method to obtain three antioxidant peptides (PF-7, GP-8, and YF-10) with biological activity, providing a theoretical basis for bioavailability of antioxidant peptides from silver carp steak and contributing to their application in new functional foods.

Molecular mechanisms underlying methotrexate-induced intestinal injury and protective strategies

Methotrexate (MTX) is a folic acid reductase inhibitor that manages various malignancies as well as immune-mediated inflammatory chronic diseases. Despite being frequently prescribed, MTX's severe multiple toxicities can occasionally limit its therapeutic potential. Intestinal toxicity is a severe adverse effect associated with the administration of MTX, and patients are significantly burdened by MTX-provoked intestinal mucositis. However, the mechanism of such intestinal toxicity is not entirely understood, mechanistic studies demonstrated oxidative stress and inflammatory reactions as key factors that lead to the development of MTX-induced intestinal injury. Besides, MTX causes intestinal cells to express pro-inflammatory cytokines like interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), which activate nuclear factor-kappa B (NF-κB). This is followed by the activation of the Janus kinase/signal transducer and activator of the transcription3 (JAK/STAT3) signaling pathway. Moreover, because of its dual anti-inflammatory and antioxidative properties, nuclear factor erythroid-2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) has been considered a critical signaling pathway that counteracts oxidative stress in MTX-induced intestinal injury. Several agents have potential protective effects in counteracting MTX-provoked intestinal injury such as omega-3 polyunsaturated fatty acids, taurine, umbelliferone, vinpocetine, perindopril, rutin, hesperidin, lycopene, quercetin, apocynin, lactobacillus, berberine, zinc, and nifuroxazide. This review aims to summarize the potential redox molecular mechanisms of MTX-induced intestinal injury and how they can be alleviated. In conclusion, studying these molecular pathways might open the way for early alleviation of the intestinal damage and the development of various agent plans to attenuate MTX-mediated intestinal injury.

The Interplay of Carveol and All-Trans Retinoic Acid (ATRA) in Experimental Parkinson's Disease: Role of Inflammasome-Mediated Pyroptosis and Nrf2

Parkinson's disease (PD) is a debilitating and the second most common neurodegenerative disorder with a high prevalence. PD has a multifaceted etiology characterized by an altered redox state and an excessive inflammatory response. Extensive research has consistently demonstrated the role of the nuclear factor E2-related factor (Nrf2) and inflammasomes, notably NLRP3 in neurodegenerative diseases. In this study, our focus was on exploring the potential neuroprotective properties of carveol in Parkinson's disease. Our findings suggest that carveol may exhibit these effects through Nrf2 and by suppressing pyroptosis. Male albino mice were treated with carveol, and the animal PD model was induced through a single intranigral dose of 2 µg/2µl lipopolysaccharide (LPS). To further demonstrate the essential role of the Nrf2 pathway, we utilized all-trans retinoic acid (ATRA) to inhibit the Nrf2. Our finding showed the induction of pyroptosis as evidenced by increased levels of NLRP3 and other inflammatory mediators, including IL-1β, iNOS, p-NFKB, and apoptotic cell death indicated by positive fluoro Jade B (FJB) staining. Moreover, increased levels of lipid peroxides and reactive oxygen species indicated a significant rise in oxidative stress due to LPS. The administration of carveol mitigates oxidative stress and suppresses inflammatory pathways through the augmentation of intrinsic antioxidant defenses, primarily via the activation of the Nrf2. Conversely, ATRA reversed carveol protective effects by increasing FJB-positive cells, inflammatory and oxidative biomarkers. Taken together, our findings suggest that carveol mitigated LPS-induced Parkinson-like symptoms, partially through the activation of the Nrf2 and downregulation of pyroptosis notably NLRP3.

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.

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.

Acute exposure to LPS induces cardiac dysfunction via the activation of the NLRP3 inflammasome

Systemic inflammation contributes to left ventricular (LV) dysfunction, however the role of the NLRP3 inflammasome in LV dysfunction in acute inflammatory conditions is unclear. This study investigated the role of the NLRP3 inflammasome in acute (24 h) cardiac structural and functional changes in vivo and in vitro in lipopolysaccharide (LPS)-induced inflammation. LPS-treated Sprague-Dawley (SD) rats showed increased LPS metabolite abundance in their LVs as measured by atmospheric pressure matrix-assisted laser desorption ionisation (AP-MALDI) mass spectrometry imaging (MSI). Echocardiography and histology showed that in LPS-exposed rats, LV internal diameter was decreased, with evidence of macrophage infiltration and oedema. However, there were no changes in LV wall thickness or collagen volume. Additionally, LPS-exposed rats exhibited impaired LV relaxation, potentially contributing to decreased stroke volume. While global systolic function was preserved, LPS exposure in SD rats resulted in impaired myocardial deformation assessed by speckle-tracking echocardiography. Exposure to LPS resulted in upregulation of the expression of components of the NLRP3 inflammasome in rodents. In vitro LPS exposure resulted in increased gene expression of NLRP3 and downstream cytokines IL-1β and IL-18, antioxidant SOD2, and elevated markers of pyroptosis (GSDMD) which were inhibited by treatment with a NLRP3 antagonist. However, LPS-induced increases in the gene expression of apoptosic markers (BAX/Bcl2) were not impacted by NLRP3 antagonism. These findings suggest that inflammation induced adverse cardiac structural and functional changes is, at least in part, mediated by the NLRP3 inflammasome in acute, high-grade inflammatory states. In addition, in vitro findings suggest that while the NLRP3 inflammasome mediates pyroptotic pathways, regulation of apoptosis that is independent of the inflammasome.

Discovery and Optimization of a Series of Vinyl Sulfoximine-Based Analogues as Potent Nrf2 Activators for the Treatment of Multiple Sclerosis

Multiple sclerosis (MS) is an immune-mediated neurodegenerative disease of the central nervous system (CNS), which leads to demyelination, axonal loss, and neurodegeneration. Increased oxidative stress and neurodegeneration have been implicated in all stages of MS, making neuroprotective therapeutics a promising strategy for its treatment. We previously have reported vinyl sulfones with antioxidative and anti-inflammatory properties that activate nuclear factor erythroid 2-related factor 2 (Nrf2), a transcription factor that induces the expression of cytoprotective genes against oxidative stress. In this study, we synthesized vinyl sulfoximine derivatives by modifying the core structure and determined therapeutic potential as Nrf2 activators. Among them, 10v effectively activated Nrf2 (EC50 = 83.5 nM) and exhibited favorable drug-like properties. 10v successfully induced expression of Nrf2-dependent antioxidant enzymes and suppressed lipopolysaccharide (LPS)-induced inflammatory responses in BV-2 microglial cells. We also confirmed that 10v effectively reversed disease progression and attenuated demyelination in an experimental autoimmune encephalitis (EAE) mouse model of MS.

Apo-12'-capsorubinal exhibits anti-inflammatory effects and activates nuclear factor erythroid 2-related factor 2 in RAW264.7 macrophages

Apocarotenoids have short carbon chain structures cleaved at a polyene-conjugated double bond. They can be biosynthesized in plants and microorganisms. Animals ingest carotenoids through food and then metabolize them into apocarotenoids. Although several apocarotenoids have been identified in the body, their precise health functions are still poorly understood. This study investigated the anti-inflammatory activities of apo-12'-capsorubinal in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. It was confirmed that apo-12'-capsorubinal was not cytotoxic to the macrophages at the concentrations tested. Apo-12'-capsorubinal treatment led to a marked downregulation of interleukin (IL)-6 protein and Il6 mRNA levels. This apocarotenoid exhibited more potent inhibitory effects than its parent carotenoids, capsanthin and capsorubin. Furthermore, apo-12'-capsorubinal, but not its parent carotenoids, promoted the nuclear accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and upregulated the expression of Nrf2-target genes, such as heme oxygenase 1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO-1), in a dose-dependent manner. Furthermore, a comparison using apo-12'-zeaxanthinal and 7,8-dihydro-8-oxo-apo-12'-zeaxanthinal revealed that the α, β-unsaturated carbonyl group on the polyene linear chain mediated the enhanced nuclear Nrf2 translocation, HO-1 expression, and inhibition of IL-6 production. In contrast, apo-12'-mytiloxanthinal, which harbored a hydroxyl group at C-8 of apo-12'-capsorubinal, did not exhibit any of these activities. These results indicated that the β carbon of the α, β-unsaturated carbonyl group in the linear part of the polyene chain is crucial to the Nrf2-activating and anti-inflammatory effects of apo-12'-capsorubinal. This study will advance our knowledge of the physiological significance of xanthophyll-derived apocarotenoids and their potential use as nutraceuticals and pharmaceuticals.

Nrf2 deficiency exacerbated pulmonary pyroptosis in maternal hypoxia-induced intrauterine growth restriction offspring mice

Maternal prenatal hypoxia is an important contributor to intrauterine growth restriction (IUGR), which impedes fetal lung maturation and leads to the development of chronic lung diseases. Although evidence suggests the involvement of pyroptosis in IUGR, the molecular mechanism of pyroptosis is still unclear. Nuclear factor erythroid 2-related factor 2 (Nrf2) has been found to potentially interact with gasdermin D (GSDMD), the key protein responsible for pyroptosis, indicating its crucial role in inhibiting pyroptosis. Therefore, we hypothesized that Nrf2 deficiency is a key molecular responsible for lung pyroptosis in maternal hypoxia-induced IUGR offspring mice. Pregnant WT and Nrf2-/- mice were exposed to hypoxia (10.5 % O2) to mimic IUGR model. We assessed body weight, lung histopathology, pulmonary angiogenesis, oxidative stress levels, as well as mRNA and protein expressions related to inflammation in the 2-week-old offspring. Additionally, we conducted a dual-luciferase reporter assay to confirm the targeting relationship between Nrf2 and GSDMD. Our findings revealed that offspring with maternal hypoxia-induced IUGR exhibited reduced birth weight, catch-up growth delay, and pulmonary dysplasia. Furthermore, we observed impaired nuclear translocation of Nrf2 and increased GSDMD-mediated pyroptosis in these offspring with IUGR. Moreover, the dual-luciferase reporter assay demonstrated that Nrf2 could directly inhibit GSDMD transcription; deficiency of Nrf2 exacerbated pyroptosis and pulmonary dysplasia in offspring with maternal hypoxia-induced IUGR. Collectively, our findings suggest that Nrf2 deficiency induces GSDMD-mediated pyroptosis and pulmonary dysplasia in offspring with maternal hypoxia-induced IUGR; thus highlighting the potential therapeutic approach of targeting Nrf2 for treating prenatal hypoxia-induced pulmonary dysplasia in offspring.

Nrf2-mediated ferroptosis inhibition: a novel approach for managing inflammatory diseases

Inflammatory diseases, including psoriasis, atherosclerosis, rheumatoid arthritis, and ulcerative colitis, are characterized by persistent inflammation. Moreover, the existing treatments for inflammatory diseases only provide temporary relief by controlling symptoms, and treatments of unstable and expensive. Therefore, new therapeutic solutions are urgently needed to address the underlying causes or symptoms of inflammatory diseases. Inflammation frequently coincides with a high level of (reactive oxygen species) ROS activation, serving as a fundamental element in numerous physiological and pathological phenotypes that can result in serious harm to the organism. Given its pivotal role in inflammation, oxidative stress, and ferroptosis, ROS represents a focal node for investigating the (nuclear factor E2-related factor 2) Nrf2 pathway and ferroptosis, both of which are intricately linked to ROS. Ferroptosis is mainly triggered by oxidative stress and involves iron-dependent lipid peroxidation. The transcription factor Nrf2 targets several genes within the ferroptosis pathway. Recent studies have shown that Nrf2 plays a significant role in three key ferroptosis-related routes, including the synthesis and metabolism of glutathione/glutathione peroxidase 4, iron metabolism, and lipid processes. As a result, ferroptosis-related treatments for inflammatory diseases have attracted much attention. Moreover, drugs targeting Nrf2 can be used to manage inflammatory conditions. This review aimed to assess ferroptosis regulation mechanism and the role of Nrf2 in ferroptosis inhibition. Therefore, this review article may provide the basis for more research regarding the treatment of inflammatory diseases through Nrf2-inhibited ferroptosis.

The role of pyroptosis in the occurrence and development of pregnancy-related diseases

Pyroptosis is a form of programmed cell death that is crucial in the development of various diseases, including autoimmune diseases, atherosclerotic diseases, cancer, and pregnancy complications. In recent years, it has gained significant attention in national and international research due to its association with inflammatory immune overactivation and its involvement in pregnancy complications such as miscarriage and preeclampsia (PE). The mechanisms discussed include the canonical pyroptosis pathway of gasdermin activation and pore formation (caspase-1-dependent pyroptosis) and the non-canonical pyroptosis pathway (cysteoaspartic enzymes other than caspase-1). These pathways work on various cellular and factorial levels to influence normal pregnancy. This review aims to summarize and analyze the pyroptosis pathways associated with abnormal pregnancies and pregnancy complications. The objective is to enhance pregnancy outcomes by identifying various targets to prevent the onset of pyroptosis.

The promising antioxidant effects of lignans: Nrf2 activation comes into view

Lignans are biologically active compounds widely distributed, recognized, and identified in seeds, fruits, and vegetables. Lignans have several intriguing bioactivities, including anti-inflammatory, antioxidant, and anticancer activities. Nrf2 controls the expression of many cytoprotective genes. Activation of Nrf2 is a promising therapeutic approach for treating and preventing diseases resulting from oxidative injury and inflammation. Lignans have been demonstrated to stimulate Nrf2 signaling in a variety of in vitro and experimental animal models. The review summarizes the findings of fourteen lignans (Schisandrin A, Schisandrin B, Schisandrian C, Magnolol, Honokiol, Sesamin, Sesamol, Sauchinone, Pinoresinol, Phyllanthin, Nectandrin B, Isoeucommin A, Arctigenin, Lariciresinol) as antioxidative and anti-inflammatory agents, affirming how Nrf2 activation affects their pharmacological effects. Therefore, lignans may offer therapeutic candidates for the treatment and prevention of various diseases and may contribute to the development of effective Nrf2 modulators.

Optimization of a Modular Nanotransporter Design for Targeted Intracellular Delivery of Photosensitizer

Modular nanotransporters (MNTs) are drug delivery systems for targeted cancer treatment. As MNTs are composed of several modules, they offer the advantage of high specificity and biocompatibility in delivering drugs to the target compartment of cancer cells. The large carrier module brings together functioning MNT modules and serves as a platform for drug attachment. The development of smaller-sized MNTs via truncation of the carrier module appears advantageous in facilitating tissue penetration. In this study, two new MNTs with a truncated carrier module containing either an N-terminal (MNTN) or a C-terminal (MNTC) part were developed by genetic engineering. Both new MNTs demonstrated a high affinity for target receptors, as revealed by fluorescent-labeled ligand-competitive binding. The liposome leakage assay proved the endosomolytic activity of MNTs. Binding to the importin heterodimer of each truncated MNT was revealed by a thermophoresis assay, while only MNTN possessed binding to Keap1. Finally, the photodynamic efficacy of the photosensitizer attached to MNTN was significantly higher than when attached to either MNTC or the original MNTs. Thus, this work reveals that MNT's carrier module can be truncated without losing MNT functionality, favoring the N-terminal part of the carrier module due to its ability to bind Keap1.

Effect of long-term inorganic arsenic exposure on erythropoietin production in vitro

Arsenic is widely present in the environment in trivalent and pentavalent forms; long-term arsenic exposure due to environmental pollution has become a problem. Previous reports have shown that 24-h exposure to arsenate (as pentavalent arsenic) potentiates erythropoietin (EPO) production via reactive oxygen species (ROS) in EPO-producing HepG2 cells. However, the effects of long-term arsenate exposure on EPO production remain unclear. In HepG2 cells subcultured for 3 weeks in the presence of arsenate, EPO mRNA levels were lower than those in untreated cells. Levels of ARSENITE METHYLTRANSFERASE mRNA, as well as those of Nuclear factor erythroid 2-related factor 2, glutathione, and superoxide dismutase proteins, were increased compared to untreated cells, but levels of malondialdehyde were not significantly altered. Thus, long-term exposure to arsenate enhances ROS scavenging, suggesting that the ROS-induced accumulation of EPO mRNA is attenuated by arsenate exposure. The induction of EPO accumulation by hypoxia also was attenuated by long-term arsenate exposure, suggesting an impairment in responsivity of EPO production. Furthermore, mRNA levels of SIRTUIN-1, which affects EPO transcription, were potentiated by long-term arsenate exposure. These results suggest that long-term arsenate exposure has multiple, distinct effects on EPO production in vitro.

Nrf2 mediated signaling axis in heart failure: Potential pharmacological receptor

Heart failure (HF) has emerged as the most pressing health concerns globally, and extant clinical therapies are accompanied by side effects and patients have a high burden of financial. The protein products of nuclear factor erythroid 2-related factor 2 (Nrf2) target genes have a variety of cardioprotective effects, including antioxidant, metabolic functions and anti-inflammatory. By evaluating established preclinical and clinical research in HF to date, we explored the potential of Nrf2 to exert unique cardioprotective functions as a novel therapeutic receptor for HF. In this review, we generalize the progression, structure, and function of Nrf2 research in the cardiovascular system. The mechanism of action of Nrf2 involved in HF as well as agonists of Nrf2 in natural compounds are summarized. Additionally, we discuss the challenges and implications for future clinical translation and application of pharmacology targeting Nrf2. It's critical to developing new drugs for HF.

Research update for ferroptosis and cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common hepatobiliary malignancy after hepatocellular carcinoma. Due to the poor treatment effect and high mortality rate of CCA, it is of great significance to explore new therapeutic targets. Ferroptosis is a type of cell death caused by iron-dependent cell oxidative injury, which is closely related to the occurrence and development of numerous diseases. Novel ideas for the prevention and treatment of related diseases have been provided by ferroptosis, which has become a focus of research in recent years. This review introduces the underlying mechanisms related to ferroptosis, as well as a research update for ferroptosis in the occurrence and development of CCA. The clinical value of ferroptosis-related regulatory mechanisms in CCA will be elucidated.

Competing endogenous RNA networks and ferroptosis in cancer: novel therapeutic targets

As a newly identified regulated cell death, ferroptosis is a metabolically driven process that relies on iron and is associated with polyunsaturated fatty acyl peroxidation, elevated levels of reactive oxygen species (ROS), and mitochondrial damage. This distinct regulated cell death is dysregulated in various cancers; activating ferroptosis in malignant cells increases cancer immunotherapy and chemoradiotherapy responses across different malignancies. Over the last decade, accumulating research has provided evidence of cross-talk between non-coding RNAs (ncRNAs) and competing endogenous RNA (ceRNA) networks and highlighted their significance in developing and progressing malignancies. Aside from pharmaceutical agents to regulate ferroptosis, recent studies have shed light on the potential of restoring dysregulated ferroptosis-related ceRNA networks in cancer treatment. The present study provides a comprehensive and up-to-date review of the ferroptosis significance, ferroptosis pathways, the role of ferroptosis in cancer immunotherapy and chemoradiotherapy, ceRNA biogenesis, and ferroptosis-regulating ceRNA networks in different cancers. The provided insights can offer the authorship with state-of-the-art findings and future perspectives regarding the ferroptosis and ferroptosis-related ceRNA networks and their implication in the treatment and determining the prognosis of affected patients.

Immunoglobulin Superfamily Containing Leucine-Rich Repeat (ISLR) Serves as a Redox Sensor That Modulates Antioxidant Capacity by Suppressing Pyruvate Kinase Isozyme M2 Activity

Cells defend against oxidative stress by enhancing antioxidant capacity, including stress-activated metabolic alterations, but the underlying intracellular signaling mechanisms remain unclear. This paper reports that immunoglobulin superfamily containing leucine-rich repeat (ISLR) functions as a redox sensor that responds to reactive oxygen species (ROS) stimulation and modulates the antioxidant capacity by suppressing pyruvate kinase isozyme M2 (PKM2) activity. Following oxidative stress, ISLR perceives ROS stimulation through its cysteine residue 19, and rapidly degrades in the autophagy-lysosome pathway. The downregulated ISLR enhances the antioxidant capacity by promoting the tetramerization of PKM2, and then enhancing the pyruvate kinase activity, PKM2-mediated glycolysis is crucial to the ISLR-mediated antioxidant capacity. In addition, our results demonstrated that, in triple-negative breast cancer, cisplatin treatment reduced the level of ISLR, and PKM2 inhibition sensitizes tumors to cisplatin by enhancing ROS production; and argued that PKM2 inhibition can synergize with cisplatin to limit tumor growth. Our results demonstrate a molecular mechanism by which cells respond to oxidative stress and modulate the redox balance.

Icariin‑curcumol promotes ferroptosis in prostate cancer cells through Nrf2/HO‑1 signaling

Ferroptosis is a form of regulatory cell death that relies on iron and reactive oxygen species (ROS) to inhibit tumors. The present study aimed to investigate whether icariin-curcumol could be a novel ferroptosis inducer in tumor inhibition. Various concentrations of icariin-curcumol were used to stimulate prostate cell lines (RWPE-2, PC-3, VCAP and DU145). Small interfering negative control (si-NC) and si-nuclear factor erythroid 2-related factor 2 (Nrf2) were used to transfect DU145 cells. Cell viability was determined by using cell counting kit-8. Ferroptosis-related factor levels were analyzed using western blotting and reverse transcription-quantitative PCR. Enzyme-linked immunosorbent assays were used to assess the ferrous (Fe2+), glutathione and malondialdehyde (MDA) content. The ROS fluorescence intensity was assessed using flow cytometry. DU145 cells were most sensitive to icariin-curcumol concentration. The Fe2+ content, ROS fluorescence intensity and MDA level gradually increased, while solute carrier family 7 member 11 (SLC7A11) level, glutathione peroxidase 4 (GPX4) level, GSH content, Nrf2 and heme oxygenase-1 (HO-1) decreased with icariin-curcumol in a dose-dependent manner. After si-Nrf2 was transfected, the cell proliferation ability, SLC7A11 and GPX4 levels declined compared with the si-NC group. In contrast to the control group, the icariin + curcumol group showed reductions in Nrf2 and HO-1 levels, cell proliferation, SLC7A11 and GPX4 levels, with an increase in Fe2+ content and ROS fluorescence intensity. Overexpression of Nrf2 reversed the regulation observed in the icariin + curcumol group. Icariin-curcumol induced ferroptosis in PCa cells, mechanistically by inhibiting the Nrf2/HO-1 signaling pathway. Icariin-curcumol could be used as a new type of ferroptosis inducer to treat PCa effectively.

Zhilong Huoxue Tongyu capsule improves myocardial ischemia/reperfusion injury via the PI3K/AKT/Nrf2 axis

INTRODUCTION

Zhilong Huoxue Tongyu Capsule (ZL) is a Chinese medicine used for the treatment of cardio-cerebral diseases. However, the pharmacological mechanisms underlying its regulation of myocardial ischemia/reperfusion injury (MI/RI) remain unclear.

PURPOSE

This study aims to investigate the effects and mechanisms of ZL on MI/RI in mice.

MATERIALS AND METHODS

C57BL/6J mice were randomly assigned to four groups: Sham group, I/R group, ZL group, and ZLY group. The MI/RI mouse model was established by ligation of the left anterior descending coronary artery for 30 minutes, followed by reperfusion for 120 minutes to restore blood perfusion. Cardiac function was evaluated using cardiac ultrasound. Histopathological changes and myocardial infarction area were assessed using Hematoxylin and eosin (H&E) staining and triphenyltetrazolium chloride (TTC) staining. The changes in oxidative stress- and ferroptosis-related markers were detected. RT-qPCR, Western blot, and ELISA were conducted to further explore the mechanism of ZL in improving MI/RI.

RESULTS

Our findings demonstrated that ZL exerted a protective effect against MI/RI by inhibiting ferroptosis, evidenced by the upregulation of antioxidant enzymes such as GSH and GPX4, coupled with the downregulation of ACSL4, a pro-ferroptosis factor. Furthermore, ZL positively impacted the PI3K/AKT/Nrf2 pathway by promoting ATPase activities and enhancing the relative protein expression of its components. Notably, the administration of a PI3K/AKT inhibitor reversed the antioxidant and anti-ferroptosis effects of ZL to some extent, suggesting a potential role for this pathway in mediating ZL's protective effects.

CONCLUSIONS

ZL protects against MI/RI-induced ferroptosis by modulating the PI3K/AKT signaling pathway, leading to increased Nrf2 expression and activation of the HO-1/GPX4 pathway. These findings shed light on the potential therapeutic mechanisms of ZL in the context of cardiovascular diseases.

Potential Targets of Natural Products for Improving Cardiac Ischemic Injury: The Role of Nrf2 Signaling Transduction

Myocardial ischemia is the leading cause of health loss from cardiovascular disease worldwide. Myocardial ischemia and hypoxia during exercise trigger the risk of sudden exercise death which, in severe cases, will further lead to myocardial infarction. The Nrf2 transcription factor is an important antioxidant regulator that is extensively engaged in biological processes such as oxidative stress, inflammatory response, apoptosis, and mitochondrial malfunction. It has a significant role in the prevention and treatment of several cardiovascular illnesses, since it can control not only the expression of several antioxidant genes, but also the target genes of associated pathological processes. Therefore, targeting Nrf2 will have great potential in the treatment of myocardial ischemic injury. Natural products are widely used to treat myocardial ischemic diseases because of their few side effects. A large number of studies have shown that the Nrf2 transcription factor can be used as an important way for natural products to alleviate myocardial ischemia. However, the specific role and related mechanism of Nrf2 in mediating natural products in the treatment of myocardial ischemia is still unclear. Therefore, this review combs the key role and possible mechanism of Nrf2 in myocardial ischemic injury, and emphatically summarizes the significant role of natural products in treating myocardial ischemic symptoms, thus providing a broad foundation for clinical transformation.

Decoding cocaine-induced proteomic adaptations in the mouse nucleus accumbens

Cocaine use disorder (CUD) is a chronic neuropsychiatric condition that results from enduring cellular and molecular adaptations. Among substance use disorders, CUD is notable for its rising prevalence and the lack of approved pharmacotherapies. The nucleus accumbens (NAc), a region that is integral to the brain's reward circuitry, plays a crucial role in the initiation and continuation of maladaptive behaviors that are intrinsic to CUD. Leveraging advancements in neuroproteomics, we undertook a proteomic analysis that spanned membrane, cytosolic, nuclear, and chromatin compartments of the NAc in a mouse model. The results unveiled immediate and sustained proteomic modifications after cocaine exposure and during prolonged withdrawal. We identified congruent protein regulatory patterns during initial cocaine exposure and reexposure after withdrawal, which contrasted with distinct patterns during withdrawal. Pronounced proteomic shifts within the membrane compartment indicated adaptive and long-lasting molecular responses prompted by cocaine withdrawal. In addition, we identified potential protein translocation events between soluble-nuclear and chromatin-bound compartments, thus providing insight into intracellular protein dynamics after cocaine exposure. Together, our findings illuminate the intricate proteomic landscape that is altered in the NAc by cocaine use and provide a dataset for future research toward potential therapeutics.

Natural products as non-covalent and covalent modulators of the KEAP1/NRF2 pathway exerting antioxidant effects

By controlling several antioxidant and detoxifying genes at the transcriptional level, including NAD(P)H quinone oxidoreductase 1 (NQO1), multidrug resistance-associated proteins (MRPs), UDP-glucuronosyltransferase (UGT), glutamate-cysteine ligase catalytic (GCLC) and modifier (GCLM) subunits, glutathione S-transferase (GST), sulfiredoxin1 (SRXN1), and heme-oxygenase-1 (HMOX1), the KEAP1/NRF2 pathway plays a crucial role in the oxidative stress response. Accordingly, the discovery of modulators of this pathway, activating cellular signaling through NRF2, and targeting the antioxidant response element (ARE) genes is pivotal for the development of effective antioxidant agents. In this context, natural products could represent promising drug candidates for supplementation to provide antioxidant capacity to human cells. In recent decades, by coupling in silico and experimental methods, several natural products have been characterized to exert antioxidant effects by targeting the KEAP1/NRF2 pathway. In this review article, we analyze several natural products that were investigated experimentally and in silico for their ability to modulate KEAP1/NRF2 by non-covalent and covalent mechanisms. These latter represent the two main sections of this article. For each class of inhibitors, we reviewed their antioxidant effects and potential therapeutic applications, and where possible, we analyzed the structure-activity relationship (SAR). Moreover, the main computational techniques used for the most promising identified compounds are detailed in this survey, providing an updated view on the development of natural products as antioxidant agents.

Cyclic Peptide Keap1-Nrf2 Protein-Protein Interaction Inhibitors: Design, Synthesis, and In Vivo Treatment of Acute Lung Injury

Directly blocking the Keap1-Nrf2 pathway is a promising strategy for the mitigation of acute lung injury (ALI). Peptide Keap1-Nrf2 inhibitors have been reported to have a high Keap1 binding affinity. However, these inhibitors showed weak activity in cells and/or animals. In this study, we designed a series of linear peptides from an Nrf2-based 9-mer Ac-LDEETGEFL-NH2. To improve the cellular activity, we further designed cyclic peptides based on the crystal complex of Keap1 with a linear peptide. Among them, cyclic 9-mer ZC9 targeting Keap1 showed a better affinity (KD2 = 51 nM). Specifically, it exhibited an acceptable water solubility (>38 mg/mL), better cell permeability, cell activity, and metabolic stability (serum t1/2 > 24 h). In the in vitro LPS-induced oxidative damages and ALI model, ZC9 showed significant dose-response reversal activity without apparent toxicity. In conclusion, our results suggested ZC9 as a lead cyclic peptide targeting the Keap1-Nrf2 pathway for ALI clinical treatment.

Fucosylated chondroitin sulfate from sea cucumber Stichopus chloronotus alleviate the intestinal barrier injury and oxidative stress damage in vitro and in vivo

This study aimed to investigate the alleviative effects of fucosylated chondroitin sulfate from sea cucumber Stichopus chloronotus (fCSSc) on the intestinal barrier injury and oxidative stress damage in vitro and in vivo. The results showed that fCS-Sc protected the intestinal barrier and improved the antioxidant function in H2O2 damaged Caco-2 cells via up-regulating the tight junction proteins and activating Keap1-Nrf2-ARE antioxidant pathway. Furthermore, administration fCS-Sc could ameliorate the weight loss and spleen index decrease in Cyclophosphamide (Cy) treated mice, improve the expressions of ZO-1, Claudin-1, Nrf2, SOD, and NQO-1 in Cy damaged colon tissue, showing significant protective effects against intestinal barrier damage and oxidative stress in vivo. fCS-Sc intervention also alleviated the gut microbiota disorder though increasing the richness and diversity of intestinal bacteria, regulating the structural composition of gut microbiota. fCS-Sc promoted the relative abundance of beneficial microbiota and inhibited the growth of harmful bacteria. This study provided a theoretical basis for the application of fCS-Sc as a prebiotic in chemotherapy.

Transcriptomic screening of novel targets of sericin in human hepatocellular carcinoma cells

Sericin, a natural protein derived from Bombyx mori, is known to ameliorate liver tissue damage; however, its molecular mechanism remains unclear. Herein, we aimed to identify the possible novel targets of sericin in hepatocytes and related cellular pathways. RNA sequencing analysis indicated that a low dose of sericin resulted in 18 differentially expressed genes (DEGs) being upregulated and 68 DEGs being downregulated, while 61 DEGs were upregulated and 265 DEGs were downregulated in response to a high dose of sericin (FDR ≤ 0.05, fold change > 1.50). Functional analysis revealed that a low dose of sericin regulated pathways associated with the complement and coagulation cascade, metallothionine, and histone demethylate (HDMs), whereas a high dose of sericin was associated with pathways involved in lipid metabolism, mitogen-activated protein kinase (MAPK) signaling and autophagy. The gene network analysis highlighted twelve genes, A2M, SERPINA5, MT2A, MT1G, MT1E, ARID5B, POU2F1, APOB, TRAF6, HSPA8, FGFR1, and OGT, as novel targets of sericin. Network analysis of transcription factor activity revealed that sericin affects NFE2L2, TFAP2C, STAT1, GATA3, CREB1 and CEBPA. Additionally, the protective effects of sericin depended on the counterregulation of APOB, POU2F1, OGT, TRAF6, and HSPA5. These findings suggest that sericin exerts hepatoprotective effects through diverse pathways at different doses, providing novel potential targets for the treatment of liver diseases.

Insights into the mechanism of transcription factors in Pb2+-induced apoptosis

The health risks associated with exposure to heavy metals, such as Pb2+, are increasingly concerning the public. Pb2+ can cause significant harm to the human body through oxidative stress, autophagy, inflammation, and DNA damage, disrupting cellular homeostasis and ultimately leading to cell death. Among these mechanisms, apoptosis is considered crucial. It has been confirmed that transcription factors play a central role as mediators during the apoptosis process. Interestingly, these transcription factors have different effects on apoptosis depending on the concentration and duration of Pb2+ exposure. In this article, we systematically summarize the significant roles of several transcription factors in Pb2+-induced apoptosis. This information provides insights into therapeutic strategies and prognostic biomarkers for diseases related to Pb2+ exposure.

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.

PSMD12 promotes non-small cell lung cancer progression through activating the Nrf2/TrxR1 pathway

BACKGROUND

Non-small cell lung cancer (NSCLC) contributes to the vast majority of cancer-related deaths. Proteasome 26S subunit, non-ATPase 12 (PSMD12), a subunit of 26S proteasome complex, is known to play the tumor-promoting role in several types of cancer but its function in NSCLC remains elusive.

OBJECTIVE

To explore the role and underlying mechanisms of PSMD12 in NSCLC.

METHODS

The PSMD12 expression in human normal lung epithelial cell line (BEAS-2B) and four NSCLC cell lines (A549, NCI-H1299, NCI-H1975, Calu-1) were determined by qRT-PCR and western blot. Malignant phenotypes of NSCLC cells were detected by CCK-8, EdU staining, immunofluorescence staining for E-cadherin, flow cytometry, and Transwell assays to assess cell viability, proliferation, epithelial-mesenchymal transition (EMT), apoptosis, migration and invasion. Dual luciferase assay was used to verify the regulatory role of transcription factor on the promoter.

RESULTS

We identified the upregulation of PSMD12 in NSCLC tissues based on the GEO datasets, which further verified in NSCLC and BEAS-2B cell lines. PSMD12 knockdown significantly suppressed malignant behaviors of NSCLC cells, including cell growth, invasion, and migration, while PSMD12 overexpression presented the opposite effects. Interestingly, we found that PSMD12 upregulated the tumor-promoting factor TrxR1 mRNA expression. For its potential mechanisms, we demonstrated that PSMD12 elevated transcription factor Nrf2 protein level and promoted Nrf2 nuclear translocation. And Nrf2 further increased TrxR1 promoter activity and enhanced TrxR1 transcription. Meanwhile, we proved that TrxR1 overexpression erased the inhibitory effect of PSMD12 knockdown.

CONCLUSION

PSMD12 promotes NSCLC progression by activating the Nrf2/TrxR1 pathway, providing a novel prognostic and therapeutic target for NSCLC treatment.

How did antibiotic growth promoters increase growth and feed efficiency in poultry?

It has been hypothesized that reducing the bioenergetic costs of gut inflammation as an explanation for the effect of antibiotic growth promoters (AGPs) on animal efficiency, framing some observations but not explaining the increase in growth rate or the prevention of infectious diseases. The host's ability to adapt to alterations in environmental conditions and to maintain health involves managing all physiological interactions that regulate homeostasis. Thus, metabolic pathways are vital in regulating physiological health as the energetic demands of the host guides most biological functions. Mitochondria are not only the metabolic heart of the cell because of their role in energy metabolism and oxidative phosphorylation, but also a central hub of signal transduction pathways that receive messages about the health and nutritional states of cells and tissues. In response, mitochondria direct cellular and tissue physiological alterations throughout the host. The endosymbiotic theory suggests that mitochondria evolved from prokaryotes, emphasizing the idea that these organelles can be affected by some antibiotics. Indeed, therapeutic levels of several antibiotics can be toxic to mitochondria, but subtherapeutic levels may improve mitochondrial function and defense mechanisms by inducing an adaptive response of the cell, resulting in mitokine production which coordinates an array of adaptive responses of the host to the stressor(s). This adaptive stress response is also observed in several bacteria species, suggesting that this protective mechanism has been preserved during evolution. Concordantly, gut microbiome modulation by subinhibitory concentration of AGPs could be the result of direct stimulation rather than inhibition of determined microbial species. In eukaryotes, these adaptive responses of the mitochondria to internal and external environmental conditions, can promote growth rate of the organism as an evolutionary strategy to overcome potential negative conditions. We hypothesize that direct and indirect subtherapeutic AGP regulation of mitochondria functional output can regulate homeostatic control mechanisms in a manner similar to those involved with disease tolerance.