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Biomolecules & Therapeutics Nov 2023According to recent evidence, ferroptosis is a major cell death mechanism in the pathogenesis of kidney injury and fibrosis. Despite the renoprotective effects of...
According to recent evidence, ferroptosis is a major cell death mechanism in the pathogenesis of kidney injury and fibrosis. Despite the renoprotective effects of classical ferroptosis inhibitors, therapeutic approaches targeting kidney ferroptosis remain limited. In this study, we assessed the renoprotective effects of melatonin and zileuton as a novel therapeutic strategy against ferroptosis-mediated kidney injury and fibrosis. First, we identified RSL3-induced ferroptosis in renal tubular epithelial HK-2 and HKC-8 cells. Lipid peroxidation and cell death induced by RSL3 were synergistically mitigated by the combination of melatonin and zileuton. Combination treatment significantly downregulated the expression of ferroptosis-associated proteins, 4-HNE and HO-1, and upregulated the expression of GPX4. The expression levels of p-AKT and p-mTOR also increased, in addition to that of NRF2 in renal tubular epithelial cells. When melatonin (20 mg/kg) and zileuton (20 mg/kg) were administered to a unilateral ureteral obstruction (UUO) mouse model, the combination significantly reduced tubular injury and fibrosis by decreasing the expression of profibrotic markers, such as α-SMA and fibronectin. More importantly, the combination ameliorated the increase in 4-HNE levels and decreased GPX4 expression in UUO mice. Overall, the combination of melatonin and zileuton was found to effectively ameliorate ferroptosis-related kidney injury by upregulating the AKT/mTOR/ NRF2 signaling pathway, suggesting a promising therapeutic strategy for protection against ferroptosis-mediated kidney injury and fibrosis.
PubMed: 37183002
DOI: 10.4062/biomolther.2023.062 -
American Journal of Physiology. Lung... Aug 2023Asthma is one of the most common noncommunicable diseases in the world. Approximately 30% of severe cases are associated with fungal sensitization, often associated with...
Asthma is one of the most common noncommunicable diseases in the world. Approximately 30% of severe cases are associated with fungal sensitization, often associated with allergy to the opportunistic mold . Leukotrienes, immunopathogenic mediators derived from the metabolism of arachidonic acid (AA) by 5-lipoxygenase (5-LOX), are often elevated in severe asthma. As such, these mediators are Food and Drug Administration-approved therapeutic targets of the antiasthmatic drugs Zileuton/Zyflo and Singulair/Montelukast. A second enzyme involved in AA metabolism is 12/15-lipoxygenase (12/15-LOX; ). Here, C57BL/6 wild-type (WT) mice subjected to experimental fungal asthma had increased expression of mRNA and increased levels of 12-HETE, a product of 12/15-LOX activity, in the lung when compared with naïve and vehicle-treated mice. Mice deficient in 12/15-LOX () demonstrated better lung function, as measured by airway hyperresponsiveness (AHR), during fungal asthma. Histological assessment revealed reduced inflammation in the lungs of mice compared with WT mice, which was corroborated by flow cytometric analysis of multiple myeloid (eosinophils and neutrophils) and lymphoid (CD4+ T and γδ T) cell populations. This was further supported by decreased levels of specific chemokines that promote the recruitment of these cells. Likewise, type 1 and 2, but not type 17 cytokines, were significantly lower in the lungs of mice. Bone marrow chimera studies revealed that the presence of 12/15-LOX in hematopoietic cells contributed to AHR during fungal asthma. Taken together, our data support the hypothesis that hematopoietic-associated 12/15-LOX contributes to type 1 and 2 responses and exacerbation of allergic fungal asthma. Humans with asthma sensitized to fungi often have more severe asthma than those who are not sensitized to fungi. Products of arachidonic acid generated via 5-lipoxygenase are often elevated in severe asthma and are successful FDA-approved drug targets. Less understood is the role of products generated via 12/15-lipoxygenase. We demonstrate that 12/15-lipoxygenase expression in hematopoietic cells contributes to type 1 and 2 responses and impaired lung function during allergic fungal asthma.
Topics: Animals; Humans; Mice; Arachidonate 15-Lipoxygenase; Arachidonate 5-Lipoxygenase; Arachidonic Acid; Asthma; Disease Models, Animal; Mice, Inbred C57BL; Mice, Knockout
PubMed: 37253655
DOI: 10.1152/ajplung.00090.2023 -
Biomedicine & Pharmacotherapy =... Jun 2023Arachidonic acid 5-lipoxygenase (5-LOX), an enzyme that synthesizes leukotrienes (LTs), is involved in cancer development including proliferation, invasion, metastasis...
Arachidonic acid 5-lipoxygenase (5-LOX), an enzyme that synthesizes leukotrienes (LTs), is involved in cancer development including proliferation, invasion, metastasis and drug resistance. However, the functional role of 5-LOX in hepatocellular carcinoma (HCC) remains to be elucidated. In this study, we analyzed the contribution of 5-LOX in HCC progression and investigated the potential of targeted therapy. Analysis of 86 resected HCC specimens and the clinical data of 362 cases of liver cancer from The Cancer Genome Atlas Liver Hepatocellular Carcinoma dataset, showed that 5-LOX expression was associated with postoperative survival. The cancer proliferative and stem cell potential were correlated with the levels of 5-LOX in CD163(+) tumor-associated macrophages (TAMs). In an HCC mouse model, CD163(+) TAMs expressed 5-LOX and produced LTB4 and LTC/D/E4; the 5-LOX inhibitor, zileuton, suppressed HCC progression. LTB4 and LTC/D/E4 promoted cancer proliferation and stem cell capacity via phosphorylation of extracellular signal-regulated kinase 1/2 and stem cell-associated genes. Taken together, we identified a novel mechanism of HCC progression in which CD163(+) TAMs express 5-LOX and produce LTB4 and LTC/D/E4, thereby enhancing the proliferative and stem cell potential of HCC cells. Furthermore, inhibition of 5-LOX activity regulates HCC progression, suggesting it has potential as a new therapeutic target.
Topics: Mice; Animals; Carcinoma, Hepatocellular; Liver Neoplasms; Arachidonate 5-Lipoxygenase; Tumor-Associated Macrophages; Leukotriene B4
PubMed: 36966664
DOI: 10.1016/j.biopha.2023.114592 -
Alternative Therapies in Health and... Jul 2023Ferroptosis is a novel type of cell-death pattern characterized by iron-dependent, oxidative stress, and lipid peroxidation. Neurological pathology, especially in spinal...
CONTEXT
Ferroptosis is a novel type of cell-death pattern characterized by iron-dependent, oxidative stress, and lipid peroxidation. Neurological pathology, especially in spinal cord injury (SCI), may involve a trace amount of ferroptosis. However, it's uncertain whether zileuton (ZIL), a selective 5-lipoxygenase (5-LO) inhibitor, can inhibit ferroptosis in SCI.
OBJECTIVE
The study intended to investigate the etiology of neuronal ferroptosis and the ameliorative effects of ZIL against it for SCI mice.
DESIGN
The research team performed an animal study.
SETTING
The study took place at the Fourth Affiliated Hospital of Harbin Medical University in Harbin, China.
ANIMALS
The animals were adult, male, C57BL/6 mice, about 20 to 25 g in weight.
INTERVENTION
The research team: (1) stimulated HT22 cells, an immortalized mouse hippocampal neuronal cell line treated with erastin, and mice induced spinal cord trauma using a moderate hit, and (2) treated the cells and mice with ZIL.
OUTCOME MEASURES
The research team measured: (1) motor function, (2) neurological damage, (3) iron content, (4) lipid oxidation, and (5) neuroinflammation and glial response.
RESULTS
ZIL administration attenuated ferroptosis and lipid peroxidation in the HT22 cells. Moreover, ZIL mitigated the ferroptosis and inflammation in the injured spinal cords. Hence, ZIL can decrease neurological damage and improve recovery of motor function, indicating an ameliorative role for ZIL in SCI.
CONCLUSIONS
ZIL has anti-ferroptosis and anti-oxidative effects in neurons, which can contribute to recovery of motor function after induction of SCI. ZIL is a promising drug for inhibiting ferroptosis and protecting neurological functions after induction of SCI.
Topics: Mice; Male; Animals; Mice, Inbred C57BL; Spinal Cord Injuries; Neurons; Iron
PubMed: 37171943
DOI: No ID Found -
Journal of Translational Medicine Dec 2023Intrahepatic cholangiocarcinoma (ICC) is poorly treated due to the presence of an inhibitory immune microenvironment. Tumor-associated macrophages (TAM) are an important...
BACKGROUND
Intrahepatic cholangiocarcinoma (ICC) is poorly treated due to the presence of an inhibitory immune microenvironment. Tumor-associated macrophages (TAM) are an important component of TME. ALOX5 is an important lipid metabolism enzyme in cancer progression, but the mechanism by which it regulates TAM to promote ICC progression is unknown. The aim of this study was to investigate the potential mechanism of TAM regulation by ALOX5 and the translational effect of targeting ALOX5.
METHODS
In this study, we investigated the association between the spatial localization of epithelial cells and TAMs by combining scRNA-seq analysis with multiplex immunofluorescence analysis. Through bulk sequencing analysis and spatial analysis, lipid metabolism genes closely related to TAM infiltration were screened. In vitro co-culture model was constructed to verify that ALOX5 and its downstream metabolite LTB4 promote M2 macrophage migration. Bulk sequencing after co-culture combined with single-cell analysis was performed to identify key pathways for up-regulation of M2 macrophage migration. Finally, the effect of CSF1R inhibitor (PLX3397) combined with ALOX5 inhibitor (Zileuton) in vivo was investigated by by xenograft tumor formation experiment in nude mice.
RESULTS
ALOX5 in ICC cells was a key lipid metabolism gene affecting the infiltration of M2 macrophages in TME. Mechanically, LTB4, a metabolite downstream of ALOX5, recruited M2 macrophages to migrate around tumor cells by binding to BLT1/BLT2 and activating the PI3K pathway, which ultimately lead to the promotion of ICC progression. Targeting CSF1R in combination with ALOX5 inhibitor effectively reduced tumor volume and M2 macrophage infiltration abundance.
CONCLUSION
In ICC, LTB4, a metabolite secreted by ALOX5 of epithelial cells, binded to BLT1/BLT2 on TAM surface to activate PI3K pathway and promote TAM migration, thus promoting ICC progression. Targeting CSF1R in combination with ALOX5 inhibitor for ICC is a promising combination therapy modality.
Topics: Animals; Mice; Humans; Phosphatidylinositol 3-Kinases; Tumor-Associated Macrophages; Mice, Nude; Leukotriene B4; Cholangiocarcinoma; Tumor Microenvironment; Cell Line, Tumor; Arachidonate 5-Lipoxygenase
PubMed: 38124204
DOI: 10.1186/s12967-023-04804-1 -
Frontiers in Pharmacology 2024Inflammation is a protective response to a variety of infectious agents. To develop a new anti-inflammatory drug, we explored a pharmacologically important thiazole...
Inflammation is a protective response to a variety of infectious agents. To develop a new anti-inflammatory drug, we explored a pharmacologically important thiazole scaffold in this study. In a multi-step synthetic approach, we synthesized seven new thiazole derivatives (-). Initially, we examined the anti-inflammatory potentials of our compounds using COX-1, COX-2, and 5-LOX enzyme assays. After confirmation, the potential compounds were subjected to analgesic and anti-inflammatory studies. The hot plate method was used for analgesia, and carrageenan-induced inflammation was also assayed. Overall, all our compounds proved to be potent inhibitors of COX-2 compared to celecoxib (IC 0.05 μM), exhibiting IC values in the range of 0.76-9.01 μM .Compounds , , and were dominant and selective COX-2 inhibitors with the lowest IC values and selectivity index (SI) values of 42, 112, and 124, respectively. Similarly, in the COX-1 assay, our compounds were relatively less potent but still encouraging. Standard aspirin exhibited an IC value of 15.32 μM. In the 5-LOX results, once again, compounds and were dominant with IC values of 23.08 and 38.46 μM, respectively. Standard zileuton exhibited an IC value of 11.00 μM. Based on the COX/LOX and SI potencies, the compounds and were subjected to analgesic and anti-inflammatory studies. Compounds and at concentrations of 5, 10, and 20 mg/kg body weight were significant in animal models. Furthermore, we explored the potential role of compounds and in various phlogistic agents. Similarly, both compounds and were also significantly potent in the anti-nociceptive assay. The molecular docking interactions of these two compounds with the target proteins of COX and LOX further strengthened their potential for use in COX/LOX pathway inhibitions.
PubMed: 38487174
DOI: 10.3389/fphar.2024.1366695 -
Viruses Oct 2023Exacerbated inflammatory responses are a hallmark of severe coronavirus disease 2019 (COVID-19). Zileuton (Zi) is a selective inhibitor of 5-lipoxygenase, an enzyme...
Exacerbated inflammatory responses are a hallmark of severe coronavirus disease 2019 (COVID-19). Zileuton (Zi) is a selective inhibitor of 5-lipoxygenase, an enzyme involved in the production of several inflammatory/pro-resolving lipid mediators. Herein, we investigated the effect of Zi treatment in a severe acute respiratory syndrome (SARS) model. Mouse hepatitis virus (MHV)3-infected mice treated with Zi significantly improved the clinical score, weight loss, cardiopulmonary function, and survival rates compared with infected untreated animals. The protection observed in Zi-treated mice was associated with a lower inflammatory score, reduced dendritic cell-producing tumor necrosis factor (TNF), and increased neutrophil-producing interleukin (IL)-10 in the lungs three days after infection (dpi). At 5 dpi, the lungs of treated mice showed an increase in Th2-, Treg CD4-, and Treg CD8-producing IL-10 and reduced Th1 infiltrating cells. Furthermore, similar results were found upon Zi treatment after SARS-CoV-2 infection in transgenic mice expressing the human angiotensin I-converting enzyme 2 (ACE2) receptor driven by the cytokeratin-18 (K18) gene promoter (K18-hACE2), significantly improving the clinical score, weight loss, and lung inflammatory score compared with untreated animals. Our data suggest that Zi protects against developing severe lung disease during SARS induced by betacoronavirus without affecting the host's capacity to deal with infection.
Topics: Humans; Mice; Animals; Lipoxygenase Inhibitors; SARS-CoV-2; COVID-19; Lung; Mice, Transgenic; Immunity, Innate; Weight Loss; Disease Models, Animal
PubMed: 37896826
DOI: 10.3390/v15102049