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Immunity Feb 2023Neuronal signals have emerged as pivotal regulators of group 2 innate lymphoid cells (ILC2s) that regulate tissue homeostasis and allergic inflammation. The molecular...
Neuronal signals have emerged as pivotal regulators of group 2 innate lymphoid cells (ILC2s) that regulate tissue homeostasis and allergic inflammation. The molecular pathways underlying the neuronal regulation of ILC2 responses in lungs remain to be fully elucidated. Here, we found that the abundance of neurotransmitter dopamine was negatively correlated with circulating ILC2 numbers and positively associated with pulmonary function in humans. Dopamine potently suppressed lung ILC2 responses in a DRD1-receptor-dependent manner. Genetic deletion of Drd1 or local ablation of dopaminergic neurons augmented ILC2 responses and allergic lung inflammation. Transcriptome and metabolic analyses revealed that dopamine impaired the mitochondrial oxidative phosphorylation (OXPHOS) pathway in ILC2s. Augmentation of OXPHOS activity with oltipraz antagonized the inhibitory effect of dopamine. Local administration of dopamine alleviated allergen-induced ILC2 responses and airway inflammation. These findings demonstrate that dopamine represents an inhibitory regulator of ILC2 responses in allergic airway inflammation.
Topics: Humans; Immunity, Innate; Dopamine; Lymphocytes; Lung; Pneumonia; Inflammation; Interleukin-33
PubMed: 36693372
DOI: 10.1016/j.immuni.2022.12.017 -
Aging Mar 2021Oxaliplatin resistance can develop in colorectal cancer (CRC), which may involve inhibition of ferroptosis, although further research is needed to understand this...
Oxaliplatin resistance can develop in colorectal cancer (CRC), which may involve inhibition of ferroptosis, although further research is needed to understand this potential mechanism. We evaluated CRC cells with acquired oxaliplatin resistance (HCT116-Or) or congenital resistance (H716) to determine whether a ferroptosis inducer (RSL3) or inhibitor (liproxstatin-1) could modulate the effects of oxaliplatin. The results suggested that induction of ferroptosis could significantly reverse the oxaliplatin resistance of the CRC cells. Bioinformatic and cytobiological searches also revealed that KIF20A was highly expressed in the oxaliplatin-resistant cell lines and was strongly correlated with survival among CRC patients. Silencing KIF20A enhanced cellular sensitivity to oxaliplatin both and , and silencing KIF20A also suppressed NUAK1 activation, while a NUAK1 agonist (ETC-1002) could reverse the oxaliplatin sensitivity of KIF20A-silenced cells. Moreover, silencing NUAK1 up-regulated the expression of PP1β, down-regulated the phosphorylation of downstream GSK3βSer9, suppressed the nuclear import of Nrf2, inhibited the expression of a ferroptosis key negative regulatory protein (GPX4), and blocked cellular resistance. Applying a Nrf2 agonist (oltipraz) also reversed the oxaliplatin sensitivity of NUAK1-silenced cells. Therefore, cellular ferroptosis may be inhibited via the KIF20A/NUAK1/PP1β/GPX4 pathway in CRC cells, which may underly the resistance of CRC to oxaliplatin.
Topics: Animals; Cell Line, Tumor; Colorectal Neoplasms; Drug Resistance, Neoplasm; Female; Ferroptosis; Glycogen Synthase Kinase 3 beta; Humans; Kinesins; Mice, Nude; Mice, SCID; NF-E2-Related Factor 2; Oxaliplatin; Phospholipid Hydroperoxide Glutathione Peroxidase; Protein Kinases; Repressor Proteins; Signal Transduction; Up-Regulation; Mice
PubMed: 33819186
DOI: 10.18632/aging.202774 -
Antioxidants (Basel, Switzerland) Aug 2020The transcription factor NF-E2 p45-related factor 2 (NRF2; encoded by ) plays a critical role in the maintenance of cellular redox and metabolic homeostasis, as well as... (Review)
Review
The transcription factor NF-E2 p45-related factor 2 (NRF2; encoded by ) plays a critical role in the maintenance of cellular redox and metabolic homeostasis, as well as the regulation of inflammation and cellular detoxication pathways. The contribution of the NRF2 pathway to organismal homeostasis is seen in many studies using cell lines and animal models, raising intense attention towards targeting its clinical promise. Over the last three decades, an expanding number of clinical studies have examined NRF2 inducers targeting an ever-widening range of diseases. Full understanding of the pharmacokinetic and pharmacodynamic properties of drug candidates rely partly on the identification, validation, and use of biomarkers to optimize clinical applications. This review focuses on results from clinical trials with four agents known to target NRF2 signaling in preclinical studies (dimethyl fumarate, bardoxolone methyl, oltipraz, and sulforaphane), and evaluates the successes and limitations of biomarkers focused on expression of NRF2 target genes and others, inflammation and oxidative stress biomarkers, carcinogen metabolism and adduct biomarkers in unavoidably exposed populations, and targeted and untargeted metabolomics. While no biomarkers excel at defining pharmacodynamic actions in this setting, it is clear that these four lead clinical compounds do touch the NRF2 pathway in humans.
PubMed: 32784785
DOI: 10.3390/antiox9080716 -
Molecular Cancer Therapeutics Nov 2008Dithiolethiones are a well-known class of cancer chemopreventive agents; the key mechanism of action of dithiolethiones involves activation of Nrf2 signaling and... (Review)
Review
Dithiolethiones are a well-known class of cancer chemopreventive agents; the key mechanism of action of dithiolethiones involves activation of Nrf2 signaling and induction of phase II enzymes. In the past, attention has been focused mainly on 4-methyl-5-pyrazinyl-3H-1,2-dithiole-3-thione (oltipraz), which showed ability as a wide-spectrum inhibitor of chemical carcinogenesis in preclinical models. However, clinical trials of oltipraz have shown questionable efficacy, and at the high doses employed in such studies, significant side effects were observed. Dithiolethiones that are markedly more effective and potent than oltipraz in both induction of phase II enzymes and inhibition of chemical carcinogenesis in preclinical studies have been identified, and these compounds have shown pronounced organ specificity in vivo. Further investigation of these compounds may lead to development of effective and safe agents for cancer prevention in humans.
Topics: Animals; Anticarcinogenic Agents; Chemoprevention; Humans; Models, Biological; Neoplasms; Pyrazines; Thiones; Thiophenes
PubMed: 19001432
DOI: 10.1158/1535-7163.MCT-08-0625 -
Preventive Medicine Sep 1993Oltipraz (4-methyl-5-(2-pyrazinyl)-1,2-dithiole-3-thione) is an antischistosomal drug presently under evaluation as a possible chemoprotective agent in humans. To date,... (Review)
Review
Oltipraz (4-methyl-5-(2-pyrazinyl)-1,2-dithiole-3-thione) is an antischistosomal drug presently under evaluation as a possible chemoprotective agent in humans. To date, oltipraz has proved effective as an inhibitor of carcinogenesis in experimental models for breast, bladder, liver, forestomach, colon, tracheal, lung, and skin cancer. Studies on the mechanisms of action of oltipraz indicate that it affects the metabolism and disposition of chemical carcinogens, principally through the induction of electrophile detoxication enzymes. While this feature is common to many different classes of both natural and synthetic experimental chemoprotectors (i.e., phenolic antioxidants, isothiocyanates, flavonoids, indoles, cinnamates, coumarins, terpenes, and others), oltipraz may offer the earliest and easiest prospect for examining the role of enzyme induction as a protective strategy in humans. Unlike the situation with many of the anutrients, substantial preclinical research has already been conducted with oltipraz to establish its safety and efficacy in animals. Hopefully, Phase I investigations will demonstrate a high tolerance for oltipraz in the chemoprotective dose range of the drug. A major concern for the success of any trial is selecting participants who are likely to adhere to the intervention as well as to all aspects of the protocol. Factors influencing participation and adherence in a trial include the design of the trial, the nature of the disease under study as well as the nature of the intervention, in particular the toxicities of the intervention (J. A. Tangrea, M. E. Adrianza, and W. E. Helsel, Cancer Epi Biomarkers Prev 1992; 1:325-330). Chemoprotection trials with oltipraz have an excellent prospect for success. Individuals with known carcinogenic exposures are likely to be interested in participation in trials designed to reduce the risks of the exposures. Moreover, the availability of intermediate markers reflecting the modulation of the biologically effective dose of environmental carcinogens as study end points will enable efficient trials to be designed.
Topics: Animals; Anticarcinogenic Agents; Clinical Trials as Topic; Drug Screening Assays, Antitumor; Female; Humans; Male; Neoplasms; Neoplasms, Experimental; Pyrazines; Thiones; Thiophenes
PubMed: 8234218
DOI: 10.1006/pmed.1993.1072 -
Frontiers in Pharmacology 2018In this study, acetaminophen (APAP)-induced acute liver injury mice model was used to investigate the effects of C2-ceramide and oltipraz on hepatocyte nuclear factor 1...
In this study, acetaminophen (APAP)-induced acute liver injury mice model was used to investigate the effects of C2-ceramide and oltipraz on hepatocyte nuclear factor 1 (HNF-1) and glutathione S-transferase A1 (GSTA1). Notably, C2-ceramide caused alteration in mice serum transaminases and liver tissue indexes, and aggravated hepatic injury, while oltipraz alleviated hepatic injury. By screening, the optimal concentrations of C2-ceramide and oltipraz were confirmed to be 120 and 150 μmol/L, respectively. In histopathology, karyolysis and more necrotic cells and bleeding spots were appeared on administration of C2-ceramide, but only a small amount of inflammatory cells infiltration was seen after oltipraz treatment. In addition, RT-PCR and western blot results revealed that the mRNA and protein expression levels of HNF-1 and GSTA1 in liver were significantly decreased ( < 0.01) with the administration of 120 μmol/L C2-ceramide. Meanwhile, GSTA1 content in serum increased up to 1.27-fold. In contrast, 150 μmol/L oltipraz incorporation to APAP model mice resulted in obvious elevation ( < 0.01) in the mRNA and protein expression levels of HNF-1 and GSTA1 in liver, and serum GSTA1 content decreased up to 0.77-fold. In conclusion, C2-ceramide could down-regulate the expression of HNF-1 and GSTA1 which exacerbated hepatic injury, while oltipraz could up-regulate the expression of HNF-1 and GSTA1 which mitigated hepatic injury.
PubMed: 30254584
DOI: 10.3389/fphar.2018.01009 -
Memorias Do Instituto Oswaldo Cruz 1987Drug resistance associated with the treatment of human schistosomiasis appears to be an emerging problem requiring more attention from the scientific community than the... (Comparative Study)
Comparative Study Review
Drug resistance associated with the treatment of human schistosomiasis appears to be an emerging problem requiring more attention from the scientific community than the subject currently receives. Drug-resistant strains of Schistosoma mansoni have been isolated by various investigators as a result of laboratory experimentation or from a combination of field and laboratory studies. Review of this data appears to indicate that the lack of susceptibility observed for some of the isolated strains cannot be ascribed solely to previous administration of antischistosome drugs and thus further studies are required to elucidate this phenomena. Strains of S. mansoni have now been identified from Brazil which are resistant to oxamniquine, hycanthone and niridazole; from Puerto Rico which are resistant to hycanthone and oxamniquine; and from Kenya which are resistant to niridazole and probably oxamniquine. Strains derived by in vitro selection and resistant to oxamniquine and possibly to oltipraz are also available. All of these strains are currently maintained in the laboratory in snails and mice, thus providing for the first time an opportunity for indepth comparative studies. Preliminary data indicates that S. haematobium strains resistant to metrifonate may be occurring in Kenya. This problem could poise great difficulty in the eventual development of antischistosomal agents. Biomphalaria glabrata from Puerto Rico and Brazil were found to be susceptible to drug-resistant S. mansoni from each country.
Topics: Animals; Anthelmintics; Biomphalaria; Drug Resistance; Helminthiasis; Helminthiasis, Animal; Humans; Mice; Schistosoma mansoni; Schistosomiasis mansoni; Schistosomicides
PubMed: 3151088
DOI: 10.1590/s0074-02761987000800025 -
Journal of Clinical Biochemistry and... Mar 2022Oltipraz, a synthetic dithiolethione, has chemopreventive effect through nuclear factor erythroid 2-related factor 2 (Nrf2) activation. Nrf2 is known to be involved in...
Oltipraz, a synthetic dithiolethione, has chemopreventive effect through nuclear factor erythroid 2-related factor 2 (Nrf2) activation. Nrf2 is known to be involved in the development of experimental steatohepatitis in rodents. In this study, to evaluate the effect of oltipraz on lipid and bile acid metabolism, wild-type and Nrf2-null mice were fed the standard diet (containing 4% soybean oil) with or without oltipraz. Based on these results, we examined the effect of oltipraz on the experimental steatohepatitis in high-fat diet (containing 4% soybean oil and 20% lard) fed Nrf2-null mice. Oltipraz induced hepatic mRNA expression of peroxisome proliferator-activated receptor α, carnitine palmityl transferase 1, and bile salt export pump by Nrf2 independent mechanisms. In Nrf2-null mice fed a high-fat diet for 12 weeks, moderate to severe inflammation and fibrosis were observed. Oral administration of oltipraz suppressed the degree of inflammation and fibrosis in Nrf2-null mouse liver fed a high-fat diet. These histopathological findings approximately corresponded to the data of mRNA expression of tumor necrosis factor α, monocyte chemoattractant protein-1, Timp-1, and collagen type 1α1. These results indicated that oltipraz administration ameliorated liver injury by Nrf2 independent manner in a model of steatohepatitis generated by Nrf2-null mice with high-fat diet.
PubMed: 35400824
DOI: 10.3164/jcbn.21-58 -
Biomedicine & Pharmacotherapy =... Jan 2024Excessive deposition of monosodium urate (MSU) crystal in the joint results in gout arthritis, which triggers severe pain and affects life quality. Oxidative stress is a...
Excessive deposition of monosodium urate (MSU) crystal in the joint results in gout arthritis, which triggers severe pain and affects life quality. Oxidative stress is a pivotal mechanism that contributes to etiology of gout pain and inflammation. Here we investigated whether activating Nrf2, which plays important roles in regulating endogenous antioxidant response, would attenuate gout arthritis via promoting antioxidant signaling in joint tissues. Gout arthritis model was established by intra-articular injection of MSU (500 μg/ankle) into the right ankle joint of mouse. Pharmacologically activating Nrf2 by activator oltipraz (50, 100 or 150 mg/kg, intraperitoneal) at 1 h before and 5, 23, 47 h after model establishment dose-dependently inhibited joint inflammation, mechanical and heat hypersensitivities in model mice. Oltipraz (100 mg/kg) reversed gait impairments without altering locomotor activity and reduced neutrophil infiltrations in ankle joints. In vitro studies revealed oltipraz (25 μM) inhibited MSU-induced ROS production in mouse macrophages and improved mitochondrial bioenergetics impairments caused by MSU. In vivo ROS imaging combined with biochemical assays confirmed the antioxidant effects of oltipraz on model mice. Nrf2 activation inhibited pro-inflammatory cytokine overproduction in ankle joint and attenuated the overexpression and enhancement in TRPV1 channel in DRG neurons innervating hind limb. Therapeutic effects of oltipraz were abolished by inhibiting Nrf2 or in Nrf2 knockout mice. These results suggest pharmacologically activating Nrf2 alleviates gout pain, gait impairments, inflammation and peripheral sensitization via Nrf2-dependent antioxidant mechanism. Targeting Nrf2 may represent a novel treatment option for gout arthritis.
Topics: Mice; Animals; Antioxidants; Gout; NF-E2-Related Factor 2; Uric Acid; Reactive Oxygen Species; Arthritis, Gouty; Inflammation; Pain
PubMed: 38042115
DOI: 10.1016/j.biopha.2023.115957 -
Journal of the American College of... Apr 2022Our previous studies have found that burn injury induces cardiac dysfunction through interruption of the antioxidant-response element (ARE) pathway in cardiac...
BACKGROUND
Our previous studies have found that burn injury induces cardiac dysfunction through interruption of the antioxidant-response element (ARE) pathway in cardiac mitochondria. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key regulator that activates many antioxidant enzymes. Oltipraz (Olti) is a Nrf2 activator and a well-known inducer of NQO1 along with other enzymes that comprise the Nrf2-associated antioxidants. We propose that Nrf2 activation will induce the ARE pathway, leading to abrogation of burn-induced cardiac dysfunction.
STUDY DESIGN
In this study, we investigated the effect of Nrf2-deficiency in mice on burn-induced cardiac dysfunction. Wild-type (WT) and Nrf2-deficient mice received 30% total body surface area burn injury and were treated with or without Olti and then harvested at 3 hours and 24 hours post burn (3 hpb and 24 hpb).
RESULTS
As expected, Nrf2-deficient mice exhibited exacerbated cardiac dysfunction after burn injury, as measured by Vevo 2100 echocardiography. Electron microscopy showed that Nrf2 depletion worsened burn injury-induced cardiac mitochondrial damage. In addition, Nrf2 depletion increased cardiac mitochondrial dysfunction and myocardial fibrosis after burn injury. Treatment with Olti ameliorated the heart dysfunction in burned Nrf2-/+ mice, improved cardiac mitochondrial structure and oxidative phosphorylation, as well as decreased cardiac fibrosis. These results suggest that Nrf2 and its downstream targets modulate cardiac function after burn injury.
CONCLUSIONS
In summary, Nrf2 depletion worsens cardiac dysfunction after burn injury. Nrf2 activation, with a drug such as Olti, offers a promising therapeutic strategy for abrogating burn-induced cardiac dysfunction.
Topics: Animals; Antioxidant Response Elements; Antioxidants; Burns; Heart Diseases; Mice; NF-E2-Related Factor 2; Signal Transduction
PubMed: 35290286
DOI: 10.1097/XCS.0000000000000119