NQO1 promotes osteogenesis and suppresses angiogenesis in DPSCs via MAPK pathway modulation.

BACKGROUND: Influence on stem cells' angiogenesis and osteogenesis of NAD(P)H Quinone Dehydrogenase 1(NQO1) has been established, but its impact on dental pulp stem cells (DPSCs) is unexplored. An important strategy for the treatment of arteriosclerosis is to inhibit calcium deposition and to promote vascular repair and angiogenesis. This study investigated the function and mechanism of NQO1 on angiogenesis and osteogenesis of DPSCs, so as to provide a new ideal for the treatment of arteriosclerosis. METHODS: Co-culture of human DPSCs and human umbilical vein endothelial cells (HUVECs) was used to detect the angiogenesis ability. Alkaline phosphatase (ALP) activity, alizarin red staining (ARS), and transplantation of HA/tricalcium phosphate with DPSCs were used to detect osteogenesis. RESULTS: NQO1 suppressed in vitro tubule formation, migration, chemotaxis, and in vivo angiogenesis, as evidenced by reduced CD31 expression. It also enhanced ALP activity, ARS, DSPP expression and osteogenesis and boosted mitochondrial function in DPSCs. CoQ10, an electron transport chain activator, counteracted the effects of NQO1 knockdown on these processes. Additionally, NQO1 downregulated MAPK signaling, which was reversed by CoQ10 supplementation in DPSCs-NQO1sh. CONCLUSIONS: NQO1 inhibited angiogenesis and promoted the osteogenesis of DPSCs by suppressing MAPK signaling pathways and enhancing mitochondrial respiration.

Mangiferin activates the nuclear factor erythroid 2-related factor pathway to protect SOD1-G93A induced NSC-34 motor neurons from oxidative stress and apoptosis.

One of the main factors in the pathophysiology of amyotrophic lateral sclerosis is oxidative stress. Mangiferin (MF), a natural plant polyphenol, has anti-inflammatory and antioxidant effects. The aim of our study was to investigate the protective effects and mechanisms of MF in the hSOD1-G93A ALS cell model. Our result revealed that MF treatment reduced the generation of reactive oxygen species (ROS) and malondialdehyde (MDA), decreased oxidative damage, and reduced apoptosis. Additionally, it was observed that MF significantly increased the synthesis of the antioxidant genes hemeoxygenase-1 and NAD(P)H: quinone oxidoreductase 1, which are downstream of the Nrf2 signaling pathway, and increased the expression and activation of nuclear factor erythroid 2-related factor 2 (Nrf2). Nrf2 knockdown greatly promoted apoptosis, which was reversed by MF treatment. To summarize, MF promoted the Nrf2 pathway and scavenged MDA and ROS to protect the ALS cell model.

[Suppression effect of secoisolariciresinol diglucoside against trans fatty acids-induced oxidative damage and inflammatory in brain of offspring mice].

OBJECTIVE: To probe into the protective effect of different dose of secoisolariciresinol diglucoside(SDG) on brain of offspring of mice anainst oxidative damage and inflammatory reaction induced by maternal exposure to trans fatty acids(TFA) during gestation, and observe the the changes of regulating Nrf2/Keap1 pathway in the course. METHODS: 30 healthy female mice(C57BL/6) were divided into 5 groups randomly, they are respectively control group, TFA-exposed group, and three SDG-intervention groups(low-(TFA+LSDG), medium-(TFA+MSDG) and high-(TFA+HSDG)). The pregnancy mice of control group and TFA group were treated with distilled water and 60 mg/kg·d TFA by gavage, in the same time, the mice of three SDG-intervention groups were treated with 60 mg/kg·d TFA by gavage and fed with feed included SDG(10, 20 and 30 mg/kg). The treatment to pregnancy mice continued to birth of offspring. After 21 days of lactation, the offspring were killed under anesthesia and the experiment was ended. The coefficient of brain was calculated. The levels of superoxide dismutase(SOD), glutathione peroxidase(GSH-Px), malondialdehyde(MDA), tumor necrosis factor-α(TNF-α), interferon-γ(IFN-γ) and amyloid-ß(Aß)of brain were detected. RT-PCR and Western Blot was used to detected gene expression and protein levels of nuclear factor erythroid-2 related factor 2(Nrf2), kelch-like ECH-associated protein 1(Keap1), quinone oxidoreductase 1(NQO1) and hemeoxygenase-l(HO-1). RESULTS: Compared with control group, the brain coefficient and Aß1-40 of offspring of TFA-group had no significant changes(P>0.05), the activity of SOD and GSH-Px reduced, the content of MDA, IFN-γ, TNF-α and Aß1-42 increased, the level of mRNA and protein expression of Nrf2, NQO1 and HO-1 decreased and the level of mRNA and protein expression of Keap1 increase because of the exposion to TFA during gestation and all the differences were statistically significant(P<0.05). Compared with TFA-group, the brain coefficient, Aß1-40 and the level of NQO1 mRNA of offspring of three SDG-intervention groups had no significant changes(P>0.05), the activity of SOD(the middle and high dose SDG intervention groups) and GSH-Px(three SDG-intervention groups) increased, the content of MDA(the middle and high dose SDG intervention groups), IFN-γ(the middle and high dose SDG intervention groups), TNF-α(three SDG-intervention groups) and Aß1-42(the middle and high dose SDG intervention groups) decreased, the mRNA expression of Nrf2 and HO-1(the middle and high dose SDG intervention groups) was up-regulated, the mRNA expression of Keap1(the middle and high dose SDG intervention group) decreased, proteic expression of Nrf2, NQO1 and HO-1 of three SDG-intervention groups increase and the level of protein of Keap1 decreased because of the intervention of SDG during gestation(P<0.05). CONCLUSION: These result suggest that maternal TFA exposure during gestation can result in oxidative stress and inflammation to brain of offspring in a way. SDG can protect brain of mice of offspring from TFA-induced oxidative injury by up-regulating the expression of mRNA and protein of Nrf2, down-regulating the expression of Keap1, accelerating expression of protein of NQO1 and HO-1 which are antioxidant protein lying downstream of pathway of Nrf2/Keap1.

Berberine sensitizes immune checkpoint blockade therapy in melanoma by NQO1 inhibition and ROS activation.

Unprecedented progress in immune checkpoint blockade (ICB) therapy has been made in cancer treatment. However, the response to ICB therapy is limited to a small subset of patients. The development of ICB sensitizers to improve cancer immunotherapy outcomes is urgently needed. Berberine (BBR), a well-known phytochemical compound isolated from many kinds of medicinal plants such as Berberis aristata, Coptis chinensis, and Phellondendron chinense Schneid, has shown the ability to inhibit the proliferation, invasion and metastasis of cancer cells. In this study, we investigated whether BBR can enhance the therapeutic benefit of ICB for melanoma, and explored the underlying mechanisms involved. The results showed that BBR could sensitize ICB to inhibit tumor growth and increased the survival rate of mice. Moreover, BBR stimulated intracellular ROS production partially by inhibiting NQO1 activity, which induced immunogenic cell death (ICD) in melanoma, elevated the levels of damage-associated molecular patterns (DAMPs), and subsequently activated DC cells and CD8 + T cells in vitro and in vivo. In conclusion, BBR is a novel ICD inducer. BBR could enhance the therapeutic benefit of ICB for melanoma. These effects were partially mediated through the inhibition of NQO1 and ROS activation.

DPP9 regulates NQO1 and ROS to promote resistance to chemotherapy in liver cancer cells.

Chemotherapy has been the standard treatment for liver cancer. However, intrinsic or acquired drug resistance remains a major barrier to successful treatment. At present, the underlying molecular mechanisms of chemoresistance in liver cancer have not been elucidated. Dipeptidyl peptidase 9 (DPP9) is a member of the dipeptidyl peptidase IV family that has been found to be highly expressed in a variety of tumors, including liver cancer. It is unclear whether DPP9 affects chemoresistance in liver cancer. In this study, we find that DPP9 weakens the responses of liver cancer cells to chemotherapy drugs by up-regulating NQO1 and inhibiting intracellular ROS levels. In terms of mechanism, DPP9 inhibits ubiquitin-mediated degradation of NRF2 protein by binding to KEAP1, up-regulates NRF2 protein levels, promotes mRNA transcription of NQO1, and inhibits intracellular ROS levels. In addition, the NQO1 inhibitor dicoumarol can enhance the efficacy of chemotherapy drugs in liver cancer cells. Collectively, our findings suggest that inhibiting DPP9/NQO1 signaling can serve as a potential therapeutic strategy for liver cancer.

Research on the Anti-Fatigue Effects and Mechanisms of Arecoline in Sleep-Deprived Mice.

The betel nut is one of the most widely consumed addictive substances in the world after nicotine, ethanol, and caffeine. Arecoline is an active ingredient from the areca nut. It has many pharmacological effects and can affect the central nervous system. In this study, we found that arecoline can relieve fatigue behavior. OBJECTIVE: This research aims to estimate the anti-fatigue effects of arecoline and explore its underlying mechanisms using a murine model of central fatigue precipitated by sleep deprivation (SD). METHODS: Seventy-two male C57BL/6 mice were randomly assigned to six groups: a control group, an SD-induced fatigue model group, a group that received Rhodiola Rosea capsules (2.5 mg/kg), and three arecoline groups, which were administered at low, medium, and high doses (10, 20, and 40 mg/kg, respectively). Following 28 days of continuous administrations, the effects of arecoline on mouse fatigue-related behaviors were assessed by behavioral tests, including grip strength, rotarod performance, and weight-bearing swimming endurance. The release levels of the related biochemical markers were measured by enzyme-linked immunosorbent assays (ELISAs). Western blotting was employed to quantify the expression levels of nuclear factor erythroid 2-related factor (Nrf2), Kelch-like ECH-associated protein 1 (Keap1), heme oxygenase 1 (HO-1), sequestosome-1 (p62), and NADPH quinone oxidoreductase 1 (NQO1) in the gastrocnemius muscle. RESULTS: Arecoline administration notably enhanced grip strength, delayed the onset of fatigue as evidenced by extended latencies in rotarod tests, and increased the duration of weight-bearing swimming in mice. In the elevated plus maze, arecoline obviously decreased both the number of entries and the total distance traveled in the open arms. Arecoline markedly decreased the contents of creatine kinase, blood urea nitrogen, lactate dehydrogenase, triglycerides, and cholesterol in the serum, while it elevated the levels of total testosterone, lactate dehydrogenase, and immunoglobulin G. Furthermore, it significantly increased the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase in the gastrocnemius muscle, reduced malondialdehyde levels, augmented hippocampal SOD and CAT activity, and elevated glycogen stores in both liver and muscle tissues. Neurotransmitter levels showed significant increases, cytokine levels were markedly reduced, and the expressions of Nrf2, Keap1, NQO1, p62, and HO-1 in brain tissues were significantly upregulated. CONCLUSIONS: This study demonstrates that arecoline has anti-fatigue activity, and the specific mechanisms are associated with elevating glucose and lipid metabolism levels, relieving oxidative stress damage, inhibiting neuroinflammatory response, and regulating neurotransmitter levels and the Keap1/Nrf2/HO-1 signaling pathway. The research provides a new direction for arecoline's potential in preventing and improving fatigue.

p-Hydroxy benzaldehyde, a phenolic compound from Nostoc commune, ameliorates DSS-induced colitis against oxidative stress via the Nrf2/HO-1/NQO-1/NF-κB/AP-1 pathway.

BACKGROUND: Ulcerative colitis (UC), a chronic idiopathic inflammatory bowel disease (IBD), presents with limited current drug treatment options. Consequently, the search for safe and effective drug for UC prevention and treatment is imperative. Our prior studies have demonstrated that the phenolic compound p-Hydroxybenzaldehyde (HD) from Nostoc commune, effectively mitigates intestinal inflammation. However, the mechanisms underlying HD's anti-inflammatory effects remain unclear. PURPOSE: This study delved into the pharmacodynamics of HD and its underlying anti-inflammation mechanisms. METHODS: For in vivo experiments, dextran sodium sulfate (DSS)-induced colitis mouse model was established. In vitro inflammation model was established using lipopolysaccharide (LPS)-induced RAW264.7 and bone marrow-derived macrophages (BMDMs). The protective effect of HD against colitis was determined by monitoring clinical symptoms and histological morphology in mice. The levels of inflammatory factors and oxidative stress markers were subsequently analyzed with enzyme-linked immunosorbent assay (ELISA) and biochemical kits. Furthermore, western blotting (WB), immunofluorescence (IF), luciferase reporter gene, drug affinity reaction target stability (DARTS) assay, molecular docking, and molecular dynamics (MD) simulation were used to determine the potential target and molecular mechanism of HD. RESULTS: Our findings indicate that HD significantly alleviated the clinical symptoms and histological morphology of colitis in mice, and curtailed the production of pro-inflammatory cytokines, including TNF-α, IL-6, IFN-γ, COX-2, and iNOS. Furthermore, HD stimulated the production of SOD, CAT, and GSH-px, enhanced total antioxidant capacity (T-AOC), and reduced MDA levels. Mechanically, HD augmented the expression of Nrf2, HO-1, and NQO-1, while concurrently downregulating the phosphorylation of p65, IκBα, c-Jun, and c-Fos. ML385 and siNrf2 largely attenuated the protective effect of HD in enteritis mice and RAW 264.7 cells, as well as the promotion of HO-1 expression levels. ZnPP-mediated HO-1 knockdown reversed HD-induced inhibition of colonic inflammation. Luciferase reporter assay and IF assay confirmed the transcriptional activation of Nrf2 by HD. DARTS analysis, molecular docking, and MD results showed high binding strength, interaction efficiency and remarkable stability between Nrf2 and HD. CONCLUSION: These outcomes extend our previous research results that HD can combat oxidative stress through the Nrf2/HO-1/NQO-1/NF-κB/AP-1 pathways, effectively alleviating colitis, and propose new targets for HD to protect against intestinal barrier damage.

Saikosaponin D potentiates the antineoplastic effects of doxorubicin in drug-resistant breast cancer through perturbing NQO1-mediated intracellular redox balance.

BACKGROUND: Drug resistance to doxorubicin (DOX) significantly limits its therapeutic efficacy in breast cancer (BC) patients. Saikosaponin D (SSD), a triterpene saponin derived from the traditional herb Radix Bupleuri, has shown promise as a chemotherapeutic sensitizer in preclinical studies due to its notable antitumor activity. However, the role and mechanism of SSD in DOX-resistant BC cells remain largely unexplored. PURPOSE: This study aimed to investigate the chemosensitizing effect of SSD on DOX-resistant BC and the underlying molecular mechanisms both in vitro and in vivo. METHODS: In vitro assays, including cell viability, clone formation, three-dimensional tumor spheroid growth, and apoptosis analysis, were conducted to evaluate the synergistic effect of SSD and DOX on resistant BC cells. Reactive oxygen species (ROS), GSH/GSSG, NADPH/NADP+, and NADH/NAD+ detections were employed to assess the impact of SSD on cellular redox homeostasis. Western blotting, cell cycle distribution assay, and DOX uptake assay were performed to further elucidate the possible antineoplastic mechanism of SSD. Finally, a subcutaneous MCF7/DOX cell xenografted model in nude mice was established to identify the in vivo anticarcinogenic effect of SSD combined with DOX. RESULTS: SSD significantly inhibited cell viability, proliferation, and clone formation, enhancing DOX's anticancer efficacy in vitro and in vivo. Mechanistically, SSD reduced STAT1, NQO1, and PGC-1α protein levels, leading to cellular redox imbalance, excessive ROS generation, and depletion of GSH, NADPH, and NADH. SSD induced DNA damage by disrupting redox homeostasis, resulting in G0/G1 phase cell cycle arrest. Additionally, SSD increased DOX accumulation in BC cells via inhibiting P-gp protein expression and efflux activity. CONCLUSION: We demonstrated for the first time that SSD enhances the sensitivity of chemoresistant BC cells to DOX by disrupting cellular redox homeostasis through inactivation of the STAT1/NQO1/PGC-1α signaling pathway. This study provides evidence for SSD as an adjuvant agent in drug-resistant BC treatment.

Prebiotic stachyose inhibits PRDX5 activity and castration-resistant prostate cancer development.

Stachyose (STA) is a prebiotic with poor oral bioavailability. In this study, we developed stachyose caproate (C6-STA), as a novel STA derivative, to demonstrate its high adsorption rate via oral administration. Pharmacokinetic analysis reveals that after absorption, the STA derived from C6-STA reaches its highest peak in the blood, liver, and kidney at 20 min, 30 min, and 12-24 h, with approximate levels of 1200 µg/mL, 0.14 µg/mL, and 0.2-0.3 µg/mL, respectively. In addition, the accumulation of STA in prostate tissues of mice with castration-resistant prostate cancer (CRPC) (1.75 µg/mg) is 10-fold higher than that in normal prostate tissues (0.14 µg/mg). The analysis also reveals that C6-STA has t1/2 of 12.8 h and Tmax of 0.25 h, indicating that it has the potential to be used as a promising drug in clinical practice. The toxicological evaluation shows no obvious side effects of C6-STA in mice administered with a 0.2 g/kg intragastric dose. Pharmacodynamic analysis and mechanism investigation of C6-STA show its ability to inhibit peroxiredoxin 5 (PRDX5) enzyme activity, disrupt PRDX5-nuclear factor erythroid 2-related factor 2 (NRF2) interaction, and decrease NAD(P)H quinone dehydrogenase 1 (NQO1) levels. NQO1 decrease further causes the accumulation of quinone radicals, which ultimately leads to the apoptosis of LNCaP cell-derived drug-tolerant persister (DTP) cells and slows CRPC progression. Our study discovered the anti-tumor activity of stachyose and shows that prebiotics have biological functions in vivo besides in the gut. Further investigation of C6-STA, especially in CRPC patients, is warranted.

Attenuation of chromium (VI) and arsenic (III)-induced oxidative stress and hepatic apoptosis by phloretin, biochanin-A, and coenzyme Q10 via activation of SIRT1/Nrf2/HO-1/NQO1 signaling.

Heavy metal contamination is an alarming concern on a global scale, as drinking tainted water significantly increases human susceptibility to heavy metals. In a realistic scenario, humans are often exposed to a combination of harmful chemicals rather than a single toxicant. Phloretin (PHL), biochanin-A (BCA), and coenzyme Q10 (CoQ10) are bioactive compounds owning plentiful pharmacological properties. Henceforth, the current research explored the putative energizing effects of selected nutraceuticals in combined chromium (Cr) and arsenic (As) intoxicated Swiss albino mice. Potassium dichromate (75 ppm) and sodium meta-arsenite (100 ppm) were given in the drinking water to induce hepatotoxicity, conjugated with PHL and BCA (50 mg/kg each), and CoQ10 (10 mg/kg) intraperitoneally for 2 weeks. After the statistical evaluation, it was observed that the hepato-somatic index, metal load, and antioxidant activity (lipid peroxidation and protein carbonyl content) increased along with the concomitant decrease in the antioxidants (catalase, glutathione-S-transferase, superoxide dismutase, reduced glutathione, and total thiol) in the Cr and As intoxicated mice. Additionally, light microscopy observations, DNA breakages, decreased silent information regulator 1 (SIRT1), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), heme oxygenase (HO-1), and NAD(P)H quinone dehydrogenase 1 (NQO1) gene expressions, together with stimulated apoptotic cell death manifested by the increased expressions of caspase 8 and caspase 3, thus, proved consistency with the aforementioned outcomes. Importantly, the treatment with nutraceuticals not only restored the antioxidant activity but also favorably altered the expressions of SIRT1, Nrf2, HO-1, and NQO1 signaling and apoptosis markers. These findings highlight the crucial role of the PHL, BCA, and CoQ10 combination in reducing Cr and As-induced hepatotoxicity in mice. By averting the triggered apoptosis in conjunction with oxidative stress, this combination increases the SIRT1, Nrf2, HO-1, and NQO1 signaling, thereby reassuringly maintaining the cellular equilibrium.

Human NQO1 as a Selective Target for Anticancer Therapeutics and Tumor Imaging.

Human NAD(P)H-quinone oxidoreductase1 (HNQO1) is a two-electron reductase antioxidant enzyme whose expression is driven by the NRF2 transcription factor highly active in the prooxidant milieu found in human malignancies. The resulting abundance of NQO1 expression (up to 200-fold) in cancers and a barely detectable expression in body tissues makes it a selective marker of neoplasms. NQO1 can catalyze the repeated futile redox cycling of certain natural and synthetic quinones to their hydroxyquinones, consuming NADPH and generating rapid bursts of cytotoxic reactive oxygen species (ROS) and H2O2. A greater level of this quinone bioactivation due to elevated NQO1 content has been recognized as a tumor-specific therapeutic strategy, which, however, has not been clinically exploited. We review here the natural and new quinones activated by NQO1, the catalytic inhibitors, and the ensuing cell death mechanisms. Further, the cancer-selective expression of NQO1 has opened excellent opportunities for distinguishing cancer cells/tissues from their normal counterparts. Given this diagnostic, prognostic, and therapeutic importance, we and others have engineered a large number of specific NQO1 turn-on small molecule probes that remain latent but release intense fluorescence groups at near-infrared and other wavelengths, following enzymatic cleavage in cancer cells and tumor masses. This sensitive visualization/quantitation and powerful imaging technology based on NQO1 expression offers promise for guided cancer surgery, and the reagents suggest a theranostic potential for NQO1-targeted chemotherapy.

Daphnetin induces ferroptosis in ovarian cancer by inhibiting NAD(P)H:Quinone oxidoreductase 1 (NQO1).

BACKGROUND: Ferroptosis, an emerging nonapoptotic, modulated cell death process characterized by iron accumulation and subsequent lipid peroxidation, has been intimately implicated in the development and progression of ovarian cancer (OC). Daphnetin (Daph), a natural product isolated from Daphne Korean Nakai, exhibits anticancer efficacy against various solid tumors. However, the specific role and potential mechanism underlying Daph-mediated modulation of ferroptosis in OC cells remain elusive. PURPOSE: This study aims to analyze the proferroptotic impacts of Daph on OC cells and to further explore the underlying mechanisms involved. STUDY DESIGN AND METHODS: We used CCK-8, wound healing and Transwell assays to assess whether Daph can inhibit the proliferation and migration of OC cells. Additionally, transmission electron microscopy (TEM), iron measurement, reactive oxygen species (ROS) analysis, lipid peroxidation assays, qRT-PCR and western blotting were utilized to evaluate the impact of Daph on ferroptosis and elucidate the potential underlying mechanism. Furthermore, RNA sequencing analysis, molecular docking analysis, cellular thermal shift assays (CETSAs) and NQO1 activity assays were used to predict and validate the binding and mechanistic interactions between Daph and NQO1. Subcutaneous tumorigenesis models were utilized to examine the effectiveness of Daph (and/or cisplatin) in vivo. RESULTS: Daph exerted antitumor effects by inducing the death and suppressing the migration of A2780 and SKOV3 cells. Further, Daph induced ferroptosis in OC cells, as evidenced by the accumulation of intracellular ferrous iron (Fe2+), ROS and lipid peroxides, as well as the decreases in the glutathione/oxidized glutathione disulfide (GSH/GSSG) ratio and the expression of ferroptosis indicators (SLC7A11 and GPX4). RNA sequencing and molecular docking analyses revealed that the direct interaction between NQO1 and Daph reduced both the activity and expression of NQO1. Importantly, NQO1 overexpression effectively alleviated the effects of Daph on proliferation, migration, and ferroptosis in vitro and in vivo. Interestingly, we also found that combination treatment with Daph, a negative regulator of NQO1, and cisplatin synergistically induced cytotoxicity in OC cells. CONCLUSION: Our findings are the firstly demonstrated that Daph acts as a novel ferroptosis inducer in OC cells by specifically targeting NQO1 and is thus a promising candidate agent for OC treatment.

Sesamolin suppresses adipocyte differentiation through Keap1-dependent Nrf2 activation in adipocytes.

Sesamolin, a lignan isolated from sesame oils, has been found to possess neuroprotective, anticancer, and free radical scavenging properties. We hypothesized that sesamolin could stimulate the activity of nuclear factor erythroid-derived 2-like 2 (Nrf2) and inhibit adipocyte differentiation of preadipocytes. The objective of this study was to investigate effects of sesamolin on adipocyte differentiation and its underlying molecular mechanisms. In this study, we determined the effects of treatment with 25 to 100 µM sesamolin on adipogenesis in cell culture systems. Sesamolin inhibited lipid accumulation and suppressed the expression of adipocyte markers during adipocyte differentiation of C3H10T1/2, 3T3-L1, and primary preadipocytes. Mechanism studies revealed that sesamolin increased Nrf2 protein expression without inducing its mRNA, leading to an increase in the expression of Nrf2 target genes such as heme oxygenase 1 and NAD(P)H:quinone oxidoreductase 1 (Nqo1) in C3H10T1/2 adipocytes and mouse embryonic fibroblasts. These effects were significantly attenuated in Nrf2 knockout (KO) mouse embryonic fibroblasts, indicating that effects of sesamolin were dependent on Nrf2. In H1299 human lung cancer cells with KO of Kelch like-ECH-associated protein 1 (Keap1), a negative regulator of Nrf2, sesamolin failed to further increase Nrf2 protein expression. However, upon reexpressing Keap1 in Keap1 KO cells, the ability of sesamolin to elevate Nrf2 protein expression was restored, highlighting the crucial role of Keap1 in sesamolin-induced Nrf2 activation. Taken together, these findings show that sesamolin can inhibit adipocyte differentiation through Keap1-mediated Nrf2 activation.

Innovative Colorimetric NQO1 Detection Strategy via Substrate Competitive and Biomimetic Cascade Reactions with a Highly Active NADH Oxidase Mimic.

NAD(P)H: quinone oxidoreductase-1 (NQO1) plays critical roles in antioxidation and abnormally overexpresses in tumors. Developing a fast and sensitive method of monitoring NQO1 will greatly promote cancer diagnosis in clinical practice. This study introduces a transformative colorimetric detection strategy for NQO1, harnessing an innovative competitive substrate mechanism between NQO1 and a new NADH oxidase (NOX) mimic, cobalt-nitrogen-doped carbon nanozyme (CoNC). This method ingeniously exploits the differential consumption of NADH in the presence of NQO1 to modulate the generation of H2O2 from CoNC catalysis, which is then quantified through a secondary, peroxidase-mimetic cascade reaction involving Prussian blue (PB) nanoparticles. This dual-stage reaction framework not only enhances the sensitivity of NQO1 detection, achieving a limit of detection as low as 0.67 µg mL-1, but also enables the differentiation between cancerous and noncancerous cells by their enzymatic activity profiles. Moreover, CoNC exhibits exceptional catalytic efficiency, with a specific activity reaching 5.2 U mg-1, significantly outperforming existing NOX mimics. Beyond mere detection, CoNC serves a dual role, acting as both a robust mimic of cytochrome c reductase (Cyt c) and a cornerstone for enzymatic regeneration, thereby broadening the scope of its biological applications. This study not only marks a significant step forward in the bioanalytical application of nanozymes but also sets the stage for their expanded use in clinical diagnostics and therapeutic monitoring.

UBA2 SUMOylates NQO1 and promotes the proliferation of hepatocellular carcinoma by modulating the MAPK pathway.

In our previous study, we found that small ubiquitin-related modifier (SUMO)-activating enzyme ubiquitin-associated-2 domain (UBA2) was upregulated in hepatocellular carcinoma (HCC) patients who were insensitive to chemoembolization. In this study, we aimed to investigate the role of UBA2 in HCC progression. Three cohorts were used to evaluate the efficacy of UBA2 as a prognostic factor for HCC. Our results indicated that UBA2 was associated with aggressive clinical behaviors and was a strong indicator of poor prognosis in HCC. In vitro experiments demonstrated that UBA2 accelerated cell growth, invasion, and migration. These results were further supported by in vivo experiments. RNA-sequencing analysis indicated NQO1 as a target of UBA2, with its levels altering following UBA2 manipulation. The results were verified by western blotting (WB) and quantitative PCR. The SUMOplot Analysis Program predicted lysine residue K240 as a modification target of UBA2, which was confirmed by immunoprecipitation (IP) assays. Subsequent mutation of NQO1 at K240 in HCC cell lines and functional assays revealed the significance of this modification. In addition, the oncogenic effect of UBA2 could be reversed by the SUMO inhibitor ML792 in vivo and in vitro. In conclusion, our study elucidated the regulatory mechanism of UBA2 in HCC and suggested that the SUMO inhibitor ML792 may be an effective combinatory treatment for patients with aberrant UBA2 expression.

Therapeutic effect of nicotinamide mononucleotide on Alzheimer's disease through activating autophagy and anti-oxidative stress.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the deposition of ß-amyloid (Aß) plaques and neurofibrillary tangles composed of tau protein in the brain. These neuropathological hallmarks contribute to cognitive impairment by inducing neuronal loss in the cerebral cortex and hippocampus. Unfortunately, current therapeutic approaches only target symptomatic relief and do not impede disease progression. Nicotinamide mononucleotide (NMN), a precursor of nicotinamide adenine dinucleotide (NAD+), has emerged as a promising candidate for the treatment of age-related neurodegenerative disorders. NMN supplementation could restore NAD+ levels, thereby alleviating neuronal damage and slowing the progression of AD and other aging-associated diseases. AD is closely associated with autophagic impairment and oxidative stress. Our in vivo experiments demonstrated that NMN could ameliorate pathological and behavioral impairments in AD mice. Specifically, NMN enhanced autophagy and promoted p-tau clearance. Meanwhile, NMN could activate the Nrf2/Keap1/NQO1 pathway, thereby reducing the oxidative stress. Immunofluorescence results demonstrated that NMN could alleviate neuronal damage in AD mice. Furthermore, in vitro results showed that the p-tau clearance and antioxidant stress effects of NMN were suppressed by autophagy inhibitor, chloroquine (CQ) or bafilomycin A1 (BafA1), in Aß-induced PC12 cells. Lastly, when Nrf2 was knocked down, the antioxidant stress, autophagy enhancement, and p-tau clearance effects of NMN were all inhibited. In conclusion, our research indicates that NMN exerts therapeutic effect against AD by activating autophagy and the Nrf2/Keap1/NQO1 pathway through a mutual regulating mechanism of autophagy and antioxidative stress. These findings highlight the promising potential of NMN for the treatment of AD.

Correlation of PD-L1 expression with CD8+ T cells and oxidative stress-related molecules NRF2 and NQO1 in esophageal squamous cell carcinoma.

Oxidative stress and the immune microenvironment both contribute to the pathogenesis of esophageal squamous cell carcinoma (ESCC). However, their interrelationships remain poorly understood. We aimed to examine the status of key molecules involved in oxidative stress and the immune microenvironment, as well as their relationships with each other and with clinicopathological features and prognosis in ESCC. The expression of programmed death-ligand 1 (PD-L1), CD8, nuclear factor erythroid-2 related factor-2 (NRF2), and NAD(P)H quinone oxidoreductase 1 (NQO1) was detected using immunohistochemistry in tissue samples from 176 patients with ESCC. We employed both combined positive score (CPS) and tumor proportion score (TPS) to evaluate PD-L1 expression and found a positive correlation between CPS and TPS. Notably, PD-L1 expression, as assessed by either CPS or TPS, was positively correlated with both NRF2 nuclear score and NQO1 score in stage II-IV ESCC. We also observed a positive correlation between the density of CD8+ T cells and PD-L1 expression. Furthermore, high levels of PD-L1 CPS, but not TPS, were associated with advanced TNM stage and lymph node metastases. Moreover, both PD-L1 CPS and the nuclear expression of NRF2 were found to be predictive of shorter overall survival in stage II-IV ESCC. By using the Mandard-tumor regression grading (TRG) system to evaluate the pathological response of tumors to neoadjuvant chemotherapy (NACT), we found that the TRG-5 group had higher NRF2 nuclear score, PD-L1 CPS, and TPS in pre-NACT biopsy samples compared with the TRG-3 + 4 group. The NQO1 scores of post-NACT surgical specimens were significantly higher in the TRG-5 group than in the TRG 3 + 4 group. In conclusion, the expression of PD-L1 is associated with aberrant NRF2 signaling pathway, advanced TNM stage, lymph node metastases, and unfavorable prognosis. The dysregulation of PD-L1 and aberrant activation of the NRF2 signaling pathway are implicated in resistance to NACT. Our findings shed light on the complex interrelationships between oxidative stress and the immune microenvironment in ESCC, which may have implications for personalized therapies and improved patient outcomes.

Engineering Magnetic Extracellular Vesicles Mimetics for Enhanced Targeting Chemodynamic Therapy to Overcome Ovary Cancer.

Chemodynamic therapy (CDT), employing metal ions to transform endogenous H2O2 into lethal hydroxyl radicals (•OH), has emerged as an effective approach for tumor treatment. Yet, its efficacy is diminished by glutathione (GSH), commonly overexpressed in tumors. Herein, a breakthrough strategy involving extracellular vesicle (EV) mimetic nanovesicles (NVs) encapsulating iron oxide nanoparticles (IONPs) and ß-Lapachone (Lapa) was developed to amplify intracellular oxidative stress. The combination, NV-IONP-Lapa, created through a serial extrusion from ovarian epithelial cells showed excellent biocompatibility and leveraged magnetic guidance to enhance endocytosis in ovarian cancer cells, resulting in selective H2O2 generation through Lapa catalysis by NADPH quinone oxidoreductase 1 (NQO1). Meanwhile, the iron released from IONPs ionization under acidic conditions triggered the conversion of H2O2 into •OH by the Fenton reaction. Additionally, the catalysis process of Lapa eliminated GSH in tumor, further amplifying oxidative stress. The designed NV-IONP-Lapa demonstrated exceptional tumor targeting, facilitating MR imaging, and enhanced tumor suppression without significant side effects. This study presents a promising NV-based drug delivery system for exploiting CDT against NQO1-overexpressing tumors by augmenting intratumoral oxidative stress.

Efficient Deep Model Ensemble Framework for Drug-Target Interaction Prediction.

Accurate prediction of Drug-Target Interactions (DTI) is crucial for drug development. Current state-of-the-art deep learning methods have significantly advanced the field; however, these methods exhibit limitations in predictive performance and the propensity for false negatives. Therefore, we propose EADTN, a simple and efficient ensemble model. We have designed an innovative feature adaptation technique to automatically extract local weights of drugs and targets, and we utilize clustering-enhanced parameter fine-tuning to overcome the issue of false negatives, thereby enhancing its reliability in drug discovery. Based on EADTN, we also propose a Shapley value-based method for identifying key drug substructures, effectively enhancing the model's interpretability. Additionally, we utilized EADTN to reveal potential interactions between NQO1 targets and the drugs SIRT-IN-1 and LY2183240, which were subsequently validated through wet-lab experiments. Experimental evidence demonstrates that EADTN consistently outperforms existing best-performing models across various data sets, promising significant benefits in fields such as drug repositioning.

Ecklonia cava Polyphenols Have a Preventive Effect on Parkinson's Disease through the Activation of the Nrf2-ARE Pathway.

Parkinson's disease (PD) is a degenerative neurological disorder defined by the deterioration and loss of dopamine-producing neurons in the substantia nigra, leading to a range of motor impairments and non-motor symptoms. The underlying mechanism of this neurodegeneration remains unclear. This research examined the neuroprotective properties of Ecklonia cava polyphenols (ECPs) in mitigating neuronal damage induced by rotenone via the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway. Using human neuroblastoma SH-SY5Y cells and PD model mice, we found that ECP, rich in the antioxidant polyphenol phlorotannin, boosted the gene expression and functionality of the antioxidant enzyme NAD(P)H quinone oxidoreductase-1. ECP also promoted Nrf2 nuclear translocation and increased p62 expression, suggesting that p62 helps sustain Nrf2 activation via a positive feedback loop. The neuroprotective effect of ECP was significantly reduced by Compound C (CC), an AMP-activated protein kinase (AMPK) inhibitor, which also suppressed Nrf2 nuclear translocation. In PD model mice, ECPs improved motor functions impaired by rotenone, as assessed by the pole test and wire-hanging test, and restored intestinal motor function and colon tissue morphology. Additionally, ECPs increased tyrosine hydroxylase expression in the substantia nigra, indicating a protective effect on dopaminergic neurons. These findings suggest that ECP has a preventative effect on PD.