OBJECTIVES: To investigate the protective effects of dexmedetomidine (DEX) against heat stress (HS)-induced oncosis in human skeletal muscle cells (HSKMCs) and its underlying mechanisms. METHODS: A HSKMC model of HS-induced oncosis were established by 43 ℃ water bath for 4 h, and the effects of treatments with 30 μmol/L DEX, ML385 (a Nrf2 inhibitor) +DEX, si-Nrf2+HS, and si-Nrf2+DEX prior to modeling on cell viability was assessed using CCK-8 assay. Oncosis characteristics were evaluated using transmission electron microscopy and Annexin V-FITC/PI flow cytometry. The oxidative stress markers (GSH, GSH-Px, MDA, SOD and ROS), mitochondrial membrane potential, energy metabolism, and inflammatory cytokines (TNF-α, IL-6 and IL-1β) in the cells were quantified using standard kits, and the expressions of porimin, caspase-3 and Nrf2 pathway proteins were analyzed using Western blotting and qRT-PCR. RESULTS: HS induced typical oncotic features in HSKMCs including organelle swelling and cytoplasmic vacuolization. DEX pretreatment significantly attenuated these changes, reduced Annexin V⁺/PI⁺ cell ratio and cellular porimin expression, and lowered the levels of ROS and MDA while restoring GSH and SOD levels. DEX pretreatment also significantly increased the mitochondrial membrane potential and ATP level, upregulated the expressions of Nrf2, p-Nrf2, HO-1 and NQO1, and suppressed the expressions of TNF-α, IL-6 and IL-1β. The protective effects of DEX were obviously attenuated by interventions with ML385 or si-Nrf2. CONCLUSIONS DEX mitigates HS-induced HSKMC oncosis by activating the Nrf2/HO-1 pathway to relieve oxidative stress, mitochondrial dysfunction, and inflammatory responses.
Humans ; Dexmedetomidine/pharmacology* ; NF-E2-Related Factor 2/metabolism* ; Oxidative Stress/drug effects* ; Heat-Shock Response/drug effects* ; Signal Transduction/drug effects* ; Membrane Potential, Mitochondrial ; Muscle, Skeletal/cytology* ; Heme Oxygenase-1/metabolism* ; Apoptosis/drug effects*

OBJECTIVES: To explore whether the antioxidant axis Nrf2/HO-1 is involved in the regulation of hippocampus injury induced by cypermethrin and its underlying mechanism. METHODS: Ten-week-old C57BL/6 mice were randomly divided into control group and cypermethrin exposure groups with low, medium, and high exposure levels. After 21 days of oral gavage of corn oil (control) or cypermethrin, the levels of MDA, T-SOD, GSH-Px and CAT in the hippocampus of the mice were examined to evaluate the oxidative stress levels. HE staining was used to observe morphological changes of the hippocampal neurons. Western blotting, immunofluorescence staining and RT-qPCR were employed to detect the protein expressions and mRNA expression of Nrf2 and HO-1 and HO-1. RESULTS: Subacute oral exposure to cypermethrin significantly increased MDA level, decreased the activities of antioxidant enzymes T-SOD, GSH-Px and CAT, and induced neuronal damage in the CA1 and CA3 regions in the hippocampus of C57BL/6 mice. Cypermethrin exposure also caused Nrf2 protein translocation from the cytoplasm to the nucleus, accompanied by upregulated expression levels of the key antioxidant factor Nrf2 and its downstream target kinase HO-1. CONCLUSIONS Cypermethrin exposure dose-dependently causes oxidative damage in the hippocampus of C57BL/6 mice, which is regulated by the Nrf2/HO-1 antioxidant pathway.
Animals ; Pyrethrins/toxicity* ; NF-E2-Related Factor 2/metabolism* ; Hippocampus/cytology* ; Mice, Inbred C57BL ; Mice ; Oxidative Stress/drug effects* ; Neurons/pathology* ; Heme Oxygenase-1/metabolism* ; Signal Transduction ; Membrane Proteins

OBJECTIVES: To investigate the neuroprotective effects of electroacupuncture (EA) preconditioning against cerebral ischemia-reperfusion injury (CIRI) mediated by gut microbiota modulation, Nrf2/HO-1 pathway activation, and ferroptosis suppression. METHODS: Adult male SD rats were divided into sham operation group, CIRI model group, and EA preconditioning group. In the latter two groups, rat models of CIRI were established by middle cerebral artery occlusion (MCAO), and in EA preconditioning group, EA was applied at Baihui (DU20) and Zusanli (ST36) for 3 days before modeling. Neurological deficits, cerebral infarction, and hippocampal pathology of the rats were evaluated using behavioral tests, TTC staining, and Nissl and HE staining, and the oxidative stress markers (MDA, ROS, and SOD), apoptosis/ferroptosis-related proteins (Bax, Bcl-2, GPX4, and SLC7A11), and changes in gut microbiota were analyzed. RESULTS: EA preconditioning significantly reduced neurological deficits, decreased infarct volume, promoted hippocampal neuronal survival, and improved structural integrity of the hippocampal neurons in MCAO rats. EA preconditioning also significantly lowered MDA and ROS and increased SOD levels, upregulated Bcl-2, GPX4, and SLC7A11 expressions, and downregulated Bax expression in the hippocampal tissue of the rats, causing also activation of Nrf2/HO-1 signaling and improvement of gut microbiota composition. CONCLUSIONS EA preconditioning alleviates CIRI in rats by suppressing ferroptosis and apoptosis, enhancing antioxidant defenses via activating Nrf2/HO-1 signaling, and regulating the gut-brain axis.
Animals ; Electroacupuncture ; NF-E2-Related Factor 2/metabolism* ; Rats, Sprague-Dawley ; Signal Transduction ; Reperfusion Injury/therapy* ; Ferroptosis ; Male ; Rats ; Brain Ischemia ; Gastrointestinal Microbiome ; Heme Oxygenase (Decyclizing)/metabolism* ; Brain/metabolism* ; Oxidative Stress ; Heme Oxygenase-1/metabolism* ; Apoptosis

OBJECTIVES: To evaluate the inhibitory effect of oridonin against proliferation of pancreatic cancer cells and the mechanism underlying the synergistic effect of low-intensity pulsed ultrasound (LIPUS). METHODS: PANC-1 cells treated with different concentrations of oridonin were examined for changes in cell proliferation using CCK-8 assay and in MDA, GSH and ATP levels using flow cytometry. The protein expressions of GPX4, Nrf2 and HO-1 in the treated cells were detected with Western blotting. The effect of Fer-1, a ferroptosis inhibitor, on proliferation of oridonin-treated cells were assessed, and the effects of oridonin combined with LIPUS on PIEZO1 protein expression was evalauted using Western blotting. A C57BL/6J mouse model bearing pancreatic cancer cell xenograft was established and treated with oridonin, LIPUS, or both, and the histological changes in the tumor tissues and tumor cell proliferation were examined with HE staining and immunohistochemistry for Ki67; the changes in GPX4 expression in the tumor tissues were detected using Western blotting and immunofluorescence staining. RESULTS: In PANC-1 cells, oridonin treatment significantly inhibited cell proliferation, increased intracellular Fe²⁺, ROS, and MDA levels, and decreased GSH and ATP levels. Oridonin also resulted in lowered GPX4 and increased HO-1 and Nrf2 protein expression levels in the cells. The combined treatment with LIPUS signficiantly enhanced the inhibitory effect of oridonin on PANC-1 cell viability in vitro and on xenograft growth in the mouse models, resulting also in more obvious reduction of the intensity of Ki67 staining and GPX4 protein expression and more pronounced increase of PIEZO1 protein expression in the tumor tissues in the mouse models. CONCLUSIONS LIPUS enhances the effect of oridonin to promote ferroptosis of pancreatic cancer cells by activating PIEZO1 through the Nrf2/HO-1/GPX4 pathway.
Ferroptosis/drug effects* ; Animals ; Pancreatic Neoplasms/metabolism* ; NF-E2-Related Factor 2/metabolism* ; Humans ; Cell Line, Tumor ; Mice ; Heme Oxygenase-1/metabolism* ; Diterpenes, Kaurane/pharmacology* ; Cell Proliferation/drug effects* ; Mice, Inbred C57BL ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Ion Channels/metabolism* ; Ultrasonic Waves ; Signal Transduction

OBJECTIVE: To observe the protective effect of Fisetin on sepsis-associated brain injury and explore its possible mechanism from the perspective of ferroptosis. METHODS: Sprague-Dawley (SD) rats (6-8-week-old male) were randomly divided into three groups: sham operation group (Sham group), colonic ligation and puncture (CLP) induced sepsis model group (CLP group) and Fisetin preprocessing group (CLP+Fisetin group), with 18 rats in each group (12 for observing survival rate and 6 for indicator testing). The CLP+Fisetin group was given Fisetin solution 50 mg×kg^-1×d^-1 by gavage continuously for 5 days before CLP, with dimethyl sulfoxide (DMSO) as the solute, while Sham group and CLP group were given the same dose of DMSO. The model was established at 2 hours after the last gavage. The general condition of each group of rats were observed, and the 10-day mortality were record. The behavioral testing (new object recognition experiment, elevated cross maze experiment) were performed after 7 days of modeling. After 24 hours of modeling, nerve reflex scoring was performed, and then the rats were euthanized and brain tissue was collected. The pathological changes of brain tissue were observed under a microscope by hematoxylin-eosin (HE) staining, the deposition of iron ion in brain tissue was observed by Prussian blue staining. The content of iron in brain tissue was determined by tissue iron kit, and the content of malondialdehyde (MDA) in brain tissue was determined by colorimetry. The expressions of tumor necrosis factor-α (TNF-α), neuron damage marker S100β, nuclear factor E2-related factor 2 (Nrf2), heme oxygenases-1 (HO-1) and glutathione peroxidase 4 (GPX4) were detected by Western blotting. RESULTS: On day 10 post-operation, 12, 3, and 7 animals survived in the Sham group, CLP group, and CLP+Fisetin group, respectively. Compared with the Sham group, rats in the CLP group showed significantly decreased nerve reflex score, new object discrimination index and open arm dwell time. HE staining showed arranged disorderly of neuronal cells, cytoplasm deep staining, nuclear condensation, unclear structures, neuron loss, and significant inflammation in the hippocampus in the hippocampus. Prussian blue staining showed iron ion deposition in the brain tissue. The contents of iron and MDA in brain tissue were elevated, and the expressions of TNF-α and S100β were up-regulated, while the expressions of Nrf2, HO-1, and GPX4 were down-regulated. Compared with the CLP group, the CLP+Fisetin group showed significantly increased neurological reflex score (7.33±1.15 vs. 4.67±1.53), improved new object discrimination index (0.44±0.02 vs. 0.32±0.04), and longer open arm dwell time (minutes: 78.33±9.29 vs. 41.15±9.64). Neuronal cells in the hippocampus were more organized, with less cytoplasmic staining, nuclear condensation, reduced neuronal loss, and fewer inflammatory cells. Iron ion deposition was reduced, and the contents of iron ions and MDA in brain tissue were decreased [iron ion (μg/g): 151.27±14.90 vs. 224.69±17.64, MDA (μmol/g): 470.0±44.3 vs. 709.3±65.4]. The expressions of TNF-α and S100β were significantly decreased (TNF-α/GAPDH: 0.651±0.060 vs. 0.896±0.022, S100β/GAPDH: 0.685±0.032 vs. 0.902±0.014), while the expressions of Nrf2, HO-1, and GPX4 were significantly increased (Nrf2/GAPDH: 0.708±0.108 vs. 0.316±0.112, HO-1/GAPDH: 0.694±0.022 vs. 0.538±0.024, GPX4/GAPDH: 0.620±0.170 vs. 0.317±0.039). All differences were statistically significant (all P < 0.05). CONCLUSION Fisetin pretreatment can inhibit ferroptosis and reduce sepsis-associated brain injury by Nrf2/HO-1/GPX4 pathway.
Animals ; Ferroptosis/drug effects* ; Rats, Sprague-Dawley ; NF-E2-Related Factor 2/metabolism* ; Sepsis/complications* ; Male ; Rats ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Neurons/drug effects* ; Signal Transduction ; Brain Injuries/metabolism* ; Flavonols ; Flavonoids/pharmacology* ; Heme Oxygenase-1/metabolism* ; Heme Oxygenase (Decyclizing)

The activation of the sirtuin1 (SIRT1)/nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway has been shown to mitigate oxidative stress-induced apoptosis and mitochondrial damage by reducing reactive oxygen species (ROS) levels. Clinical trials have demonstrated that Zhongfeng Xingnao Liquid (ZFXN) ameliorates post-stroke cognitive impairment (PSCI). However, the underlying mechanism, particularly whether it involves protecting mitochondria and inhibiting apoptosis through the SIRT1/Nrf2/HO-1 pathway, remains unclear. This study employed an oxygen-glucose deprivation (OGD) cell model using SH-SY5Y cells and induced PSCI in rats through modified bilateral carotid artery ligation (2VO). The effects of ZFXN on learning and memory, neuroprotective activity, mitochondrial function, oxidative stress, and the SIRT1/Nrf2/HO-1 pathway were evaluated both in vivo and in vitro. Results indicated that ZFXN significantly increased the B-cell lymphoma 2 (Bcl2)/Bcl2-associated X (Bax) ratio, reduced terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling (TUNEL)⁺ cells, and markedly improved cognition, synaptic plasticity, and neuronal function in the hippocampus and cortex. Furthermore, ZFXN exhibited potent antioxidant activity, evidenced by decreased ROS and malondialdehyde (MDA) content and increased superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) levels. ZFXN also demonstrated considerable enhancement of mitochondrial membrane potential (MMP), Tom20 fluorescence intensity, adenosine triphosphate (ATP) and energy charge (EC) levels, and mitochondrial complex I and III activity, thereby inhibiting mitochondrial damage. Additionally, ZFXN significantly increased SIRT1 activity and elevated SIRT1, nuclear Nrf2, and HO-1 levels. Notably, these effects were substantially counteracted when SIRT1 was suppressed by the inhibitor EX-527 in vitro. In conclusion, ZFXN alleviates PSCI by activating the SIRT1/Nrf2/HO-1 pathway and preventing mitochondrial damage.
Sirtuin 1/genetics* ; Animals ; NF-E2-Related Factor 2/genetics* ; Cognitive Dysfunction/genetics* ; Male ; Rats, Sprague-Dawley ; Rats ; Humans ; Signal Transduction/drug effects* ; Drugs, Chinese Herbal/administration & dosage* ; Heme Oxygenase-1/genetics* ; Stroke/complications* ; Oxidative Stress/drug effects* ; Apoptosis/drug effects* ; Mitochondria/metabolism* ; Reactive Oxygen Species/metabolism* ; Neuroprotective Agents

This study identified six novel azaphilones, isochromophilones G-L (1-6), and three novel biosynthetically related congeners (7-9) from Diaporthe sp. SCSIO 41011. The structures and absolute configurations were elucidated through comprehensive spectroscopic analyses combined with experimental and calculated electronic circular dichroism (ECD) spectra. Significantly, three highly oxygenated azaphilones contain an acetyl group at the terminal chain (4) or linear conjugated polyenoid moieties (5 and 6), which occur infrequently in the azaphilone family. Additionally, several compounds demonstrated inhibition of lipopolysaccharide (LPS)-induced nuclear factor kappa-B (NF-κB) activation in RAW 264.7 macrophages at 20 μmol·L^-1. The novel compound (1) effectively inhibited receptor activator of NF-κB ligand (RANKL)-induced osteoclast differentiation without exhibiting cytotoxicity in bone marrow and RAW 264.7 macrophages, indicating its potential as a promising lead compound for osteolytic disease treatment. This research presents the first documented evidence of azaphilone derivatives as inhibitors of RANKL-induced osteoclastogenesis.
Animals ; Mice ; RANK Ligand/genetics* ; RAW 264.7 Cells ; Osteoclasts/metabolism* ; Benzopyrans/isolation & purification* ; Osteogenesis/drug effects* ; Macrophages/metabolism* ; Molecular Structure ; Pigments, Biological/isolation & purification* ; Ascomycota/chemistry* ; NF-kappa B/genetics* ; Cell Differentiation/drug effects*

Gastric cancer (GC) is characterized by high morbidity and mortality rates. Chinese agarwood comprises the resin-containing wood of Aquilaria sinensis (Lour.) Gilg., traditionally utilized for treating asthma, cardiac ischemia, and tumors. However, comprehensive research regarding its anti-GC effects and underlying mechanisms remains limited. In this study, Chinese agarwood petroleum ether extract (CAPEE) demonstrated potent cytotoxicity against human GC cells, with half maximal inhibitory concentration (IC₅₀) values for AGS, HGC27, and MGC803 cells of 2.89, 2.46, and 2.37 μg·mL^-1, respectively, at 48 h. CAPEE significantly induced apoptosis in these GC cells, with B-cell lymphoma-2 (BCL-2) associated X protein (BAX)/BCL-2 antagonist killer 1 (BAK) likely mediating CAPEE-induced apoptosis. Furthermore, CAPEE induced G₀/G₁ phase cell cycle arrest in human GC cells via activation of the deoxyribonucleic acid (DNA) damage-p21-cyclin D1/cyclin-dependent kinase 4 (CDK4) signaling axis, and increased Fe²⁺, lipid peroxides and reactive oxygen species (ROS) levels, thereby inducing ferroptosis. Ribonucleic acid (RNA) sequencing, real-time quantitative polymerase chain reaction (RT-qPCR), and Western blotting analyses revealed CAPEE-mediated upregulation of heme oxygenase-1 (HO-1) in human GC cells. RNA interference studies demonstrated that HO-1 knockdown reduced CAPEE sensitivity and inhibited CAPEE-induced ferroptosis in human GC cells. Additionally, CAPEE administration exhibited robust in vivo anti-GC activity without significant toxicity in nude mice while inhibiting tumor cell growth and promoting apoptosis in tumor tissues. These findings indicate that CAPEE suppresses human GC cell growth through upregulation of the DNA damage-p21-cyclin D1/CDK4 signaling axis and HO-1-mediated ferroptosis, suggesting its potential as a candidate drug for GC treatment.
Animals ; Humans ; Mice ; Antineoplastic Agents, Phytogenic ; Apoptosis/drug effects* ; Cell Line, Tumor ; Cyclin D1/genetics* ; Cyclin-Dependent Kinase 4/genetics* ; DNA Damage/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Ferroptosis/drug effects* ; G1 Phase Cell Cycle Checkpoints/drug effects* ; Heme Oxygenase-1/genetics* ; Mice, Inbred BALB C ; Mice, Nude ; Plant Extracts/pharmacology* ; Stomach Neoplasms/physiopathology* ; Thymelaeaceae/chemistry* ; Up-Regulation/drug effects*

Flavonoid 3-O-glucosyltransferase (3GT) is a key enzyme in the glucosidation of anthocyanins. To investigate the 3GT gene in rhododendron, we cloned an open reading frame (ORF) of 3GT gene (named Rh3GT) from Rhododendron hybridum Hort (Red cultivar) and then characterized this gene and the deduced protein in terms of the biochemical characteristics, expression level, and enzymatic function. The results showed that Rh3GT had a full length of 993 bp and encoded 330 amino acid residues. The deduced protein was hydrophilic, stable, weak acid, belonging to the glycosyltransferase family (GT-B type), with glutamine (Q) at position 44 in the PSPG box. The phylogenetic analysis showed that Rh3GT was most closely related to Vc3GT from Vaccinium corymbosum and Vm3GT from Vaccinium myrtillus. Rh3GT was expressed in the stems, leaves, and flowers and almost not expressed in the roots, with the highest expression level in petals during full blooming stage. Introduction of pCAMBIAL1302-Rh3GT into petals significantly up-regulated the expression level of Rh3GT and increased the total anthocyanin accumulation. Rh3GT was successfully expressed in Escherichia coli BL21 in the form of inclusion bodies with a size of about 36 kDa. The results of HPLC showed that the recombinant Rh3GT after denaturation, purification, and dilution could catalyze the synthesis of cyanidin and UDP-glucose to synthesize cyanidin 3-O-glucoside, indicating that the expressed protein had 3GT activity. This study provides basic data for further studying the molecular regulation mechanism of anthocyanin biosynthesis and theoretical support for molecular breeding of rhododendron.
Rhododendron/classification* ; Glucosyltransferases/metabolism* ; Cloning, Molecular ; Escherichia coli/metabolism* ; Recombinant Proteins/biosynthesis* ; Anthocyanins/biosynthesis* ; Phylogeny ; Plant Proteins/metabolism* ; Amino Acid Sequence

Hormesis effect has been observed in the secondary metabolite synthesis of microorganisms induced by rare earth elements. However, the underlying molecular mechanism remains unclear. To analyze the molecular mechanism of the regulatory effect of Rhodotorula mucilaginosa in the presence of lanthanum chloride, different concentrations of lanthanum chloride were added to the fermentation medium of Rhodotorula mucilaginosa, and the carotenoid content was subsequently measured. It was found that the concentrations of La³⁺ exerting the promotional and inhibitory effects were 0-100 mg/L and 100-400 mg/L, respectively. Furthermore, the expression of 33 genes and the synthesis of 55 metabolites were observed to be up-regulated, while the expression of 85 genes and the synthesis of 123 metabolites were found to be down-regulated at the concentration range of the promotional effect. Notably, the expression of carotenoid synthesis-related genes except AL1 was up-regulated. Additionally, the content of β-carotene, lycopene, and astaxanthin demonstrated increases of 10.74%, 5.02%, and 3.22%, respectively. The expression of 5 genes and the synthesis of 91 metabolites were up-regulated, while the expression of 35 genes and the synthesis of 138 metabolites were down-regulated at the concentration range of the inhibitory effect. Meanwhile, the content of β-carotene, lycopene, and astaxanthin decreased by 21.73%, 34.81%, and 35.51%, respectively. In summary, appropriate concentrations of rare earth ions can regulate the synthesis of secondary metabolites by modulating the activities of various enzymes involved in metabolic pathways, thereby exerting the hormesis effect. The findings of this study not only contribute to our comprehension for the mechanism of rare earth elements in organisms but also offer a promising avenue for the utilization of rare earth elements in diverse fields, including agriculture, pharmaceuticals, and healthcare.
Lanthanum/pharmacology* ; Rhodotorula/genetics* ; Carotenoids/metabolism* ; Hormesis/drug effects* ; Fermentation ; Multiomics