OBJECTIVES: The purinergic receptor P2X2 (P2RX2) encodes an ATP-gated ion channel permeable to Na⁺, K⁺, and especially Ca²⁺. Loss-of-function mutations in P2RX2 are known to cause autosomal dominant nonsyndromic deafness 41 (DFNA41), which manifests as high-frequency hearing loss, accelerated presbycusis, and increased susceptibility to noise-induced damage. Zebrafish, owing to their small size, rapid development, high fecundity, transparent embryos, and high gene conservation with humans, provide an ideal model for studying human diseases and developmental mechanisms. This study aims to generate a p2rx2 knockout zebrafish model using CRISPR/Cas9 gene editing system to investigate the effect of p2rx2 deficiency on the auditory system, providing a basis for understanding P2RX2-related hearing loss and developing gene therapy strategies. METHODS: Two CRISPR targets (sgRNA1 and sgRNA2) spaced 47 bp apart were designed within the zebrafish p2rx2 gene. Synthesized sgRNAs and Cas9 protein were microinjected into single-cell stage Tübingen (TU)-strain zebrafish embryos. PCR and gel electrophoresis verified editing efficiency at 36 hours post-fertilization (hpf). Surviving embryos were raised to adulthood (F0), tail-clipped, genotyped, and screened for positive mosaics. F1 heterozygotes were generated by outcrossing, and F2 homozygous mutants were obtained by intercrossing. Polymerase chain reaction (PCR) combined with sequencing verified mutation type and heritability. At 5 days post-fertilization (dpf), YO-PRO-1 staining was used to examine hair cell morphology and count in lateral line neuromasts and the otolith region. Auditory evoked potential (AEP) thresholds at 600, 800, 1 000, and 2 000 Hz were measured in nine 4-month-old wild type and mutant zebrafish per group. RESULTS: A stable p2rx2 knockout zebrafish line was successfully established. Sequencing revealed a 66 bp insertion at the first target site introducing a premature stop codon (TAA), leading to early termination of protein translation and loss of function. Embryos developed normally with no gross malformations. At 5 dpf, mutants exhibited significantly reduced hair cell density in the otolith region compared with wild type, although lateral line neuromasts were unaffected. AEP testing showed significantly elevated auditory thresholds at all 4 frequencies in homozygous mutants compared with wild type (all P<0.001), indicating reduced hearing sensitivity. CONCLUSIONS We successfully generated a p2rx2 loss-of-function zebrafish model using CRISPR/Cas9 technology. p2rx2 deficiency caused hair cell defects in the otolith region and increased auditory thresholds across frequencies, indicating its key role in maintaining zebrafish auditory hair cell function and hearing perception. The phenotype's restriction to the otolith region suggests tissue-specific roles of p2rx2 in sensory organs. This model provides a valuable tool for elucidating the molecular mechanisms of P2RX2-related hearing loss and for screening otoprotective drugs and developing gene therapies.
Animals ; Zebrafish/genetics* ; Receptors, Purinergic P2X2/deficiency* ; CRISPR-Cas Systems/genetics* ; Gene Knockout Techniques ; Phenotype ; Zebrafish Proteins/genetics* ; Disease Models, Animal

OBJECTIVES: To observe the effect of 4-(arylethynyl)-pyrrolo[2,3-d] pyrimidine (10b) on post-traumatic stress disorder (PTSD)-like behaviors and ERK1/2-SGK1 signaling pathway in mice. METHODS: C57BL/6 mouse models exposed to single prolonged stress (SPS) were treated with daily gavage of saline, 10b at low, moderate and high doses, or paroxetine for 14 days. The changes in PTSD-like behaviors of SPS mice with different treatments were observed using behavioral tests. Western blotting and immunofluorescence assay were used to detect the protein expression levels of mGluR5, p-ERK, and SGK1 in the hippocampus of the mice. Pathological changes in the liver and kidney tissues of the mice were examined using HE staining. Molecular docking and molecular dynamics analyses were employed to evaluate the binding stability between the compound 10b and mGluR5. RESULTS: Compared to the normal control mice, the SPS mice exhibited obvious PTSD-like behaviors with increased hippocampal expressions of mGluR5 and p-ERK proteins and decreased SGK1 protein expression. Compound 10b significantly ameliorated behavioral abnormalities in SPS mice, inhibited mGluR5 expression, and reversed the dysregulation of p-ERK and SGK1. No obvious liver or kidney toxicity was observed after 10b treatment. Molecular docking and dynamics studies demonstrated a stable interaction between 10b and mGluR5. CONCLUSIONS The compound 10b ameliorates PTSD-like behaviors induced by SPS in mice possibly by inhibiting mGluR5 expression to modulate the ERK1/2-SGK1 signaling pathway.
Animals ; Stress Disorders, Post-Traumatic/drug therapy* ; Receptor, Metabotropic Glutamate 5/metabolism* ; Mice, Inbred C57BL ; Mice ; Protein Serine-Threonine Kinases/metabolism* ; Pyrimidines/pharmacology* ; Immediate-Early Proteins/metabolism* ; Signal Transduction/drug effects* ; MAP Kinase Signaling System/drug effects* ; Male ; Molecular Docking Simulation ; Hippocampus/metabolism*

OBJECTIVES: To investigate the role of sphingosine-1-phosphate receptor 5 (S1PR5) in modulating barrier function of mouse brain microvascular endothelial cells with oxygen-glucose deprivation and reoxygenation (OGD/R). METHODS: Mouse brain microvascular endothelial cells (bEnd.3) were exposed to OGD/R to induce barrier dysfunction following treatment with S1PR5-specific agonist A971432 or lentivirus-mediated transfection with a S1PR5-specific siRNA, a S1PR5-overexpressing plasmid, or their respective negative control sequences. The changes in viability and endothelial barrier permeability of the treated cells were evaluated with CCK-8 assay and FITC-dextran permeability assay; the levels of intracellular reactive oxygen species (ROS) and localization and expression levels of the proteins related with barrier function and oxidative stress were detected using immunofluorescence staining, DCFH-DA probe and Western blotting. RESULTS: S1PR5 activation obviously enhanced viability of bEnd.3 cells exposed to OGD/R (P<0.0001). Both activation and overexpression of S1PR5 reduced FITC-dextran leakage, while S1PR5 knockdown significantly increased FITC-dextran leakage in the exposed bEnd.3 cells. Activation and overexpression of S1PR5 both increased the cellular expressions of the barrier proteins ZO-1 and occludin, while S1PR5 knockdown produced the opposite effect. In cells exposed to OGD/R, ROS production was significantly reduced by S1PR5 activation and overexpression but increased following S1PR5 knockdown. Overexpression of S1PR5 obviously increased the expressions of the antioxidant proteins Nrf2, HO-1 and SOD2 in the exposed cells. CONCLUSIONS S1PR5 activation and overexpression significantly improve cell viability and reduce permeability of a mouse brain microvascular endothelial cell model of OGD/R, the mechanism of which may involve the reduction in ROS production and upregulation of the antioxidant proteins.
Animals ; Mice ; Oxidative Stress ; Endothelial Cells/cytology* ; Brain/blood supply* ; Reactive Oxygen Species/metabolism* ; Receptors, Lysosphingolipid/metabolism* ; Sphingosine-1-Phosphate Receptors ; Blood-Brain Barrier/metabolism* ; Glucose ; Cell Line ; Oxygen/metabolism* ; NF-E2-Related Factor 2/metabolism*

OBJECTIVES: To investigate the effects of live combined Bacillus subtilis and Enterococcus faecium (LCBE) on glucose and lipid metabolism in mice with type 2 diabetes mellitus (T2DM) and circadian rhythm disorder (CRD) and explore the possible mechanisms. METHODS: KM mice were randomized into normal diet (ND) group (n=8), high-fat diet (HFD) group (n=8), and rhythm-intervention with HFD group (n=16). After 8 weeks of feeding, the mice were given an intraperitoneal injection of streptozotocin (100 mg/kg) to induce T2DM. The mice in CRD-T2DM group were further randomized into two equal groups for treatment with LCBE (225 mg/kg) or saline by gavage; the mice in ND and HFD groups also received saline gavage for 8 weeks. Blood glucose level of the mice was measured using a glucometer, and serum levels of Bmal1, PER2, insulin, C-peptide and lipids were determined with ELISA. Colon morphology and hepatic lipid metabolism of the mice were examined using HE staining and Oil Red O staining, respectively, and fecal short-chain fatty acids (SCFAs) was detected using LC-MS; GPR43 and GLP-1 expression levels were analyzed using RT-qPCR and Western blotting. RESULTS: Compared with those in CRD-T2DM group, the LCBE-treated mice exhibited significant body weight loss, lowered levels of PER2, insulin, C-peptide, total cholesterol (TC) and LDL-C, and increased levels of Bmal1 and HDL-C levels. LCBE treatment significantly increased SCFAs, upregulated GPR43 and GLP-1 expressions at both the mRNA and protein levels, and improved hepatic steatosis and colon histology. CONCLUSIONS LCBE ameliorates lipid metabolism disorder in CRD-T2DM mice by reducing body weight and improving lipid profiles and circadian regulators possibly via the SCFAs/GPR43/GLP-1 pathway.
Animals ; Mice ; Lipid Metabolism ; Diabetes Mellitus, Type 2/metabolism* ; Enterococcus faecium ; Glucagon-Like Peptide 1/metabolism* ; Bacillus subtilis ; Diabetes Mellitus, Experimental/metabolism* ; Circadian Rhythm ; Blood Glucose/metabolism* ; Receptors, G-Protein-Coupled/metabolism* ; Fatty Acids, Volatile/metabolism* ; Male ; Chronobiology Disorders/metabolism*

OBJECTIVES: To explore the toxic mechanism of Clostridium perfringens Beta1 toxin mediated by P2X7 receptor-induced calcium dyshomeostasis. METHODS: Ten-day-old BALB/c mice were randomly divided into control group, recombinant Beta1 toxin (rCPB1) group, PD151746 group, and PD151746+rCPB1 group, and all the treatment agents were administered by gavage. The changes in expressions of inflammatory factors in the jejunum of the mice were detected using antibody chip technology to explore the regulatory role of calcium dyshomeostasis in Beta1 toxin-induced inflammatory injury level. In the cell experiment, THP-1 cells were transfected with a si-RNA targeting P2X7 receptor and treated with rCPB1, and the changes in cell survival rate, levels of Ca²⁺, ROS and ATP, and expressions of pyroptosis and ferroptosis markers were determined. RESULTS: Oral administration of rCPB1 significantly increased the levels of inflammatory cytokines in the jejunal tissue of the neonatal mice, but their levels were significantly decreased after treatment with PD151746. In THP-1 cells, rCPB1 treatment significantly decreased cell survival and increased the levels of Ca²⁺, ROS, ATP and the expressions of pyroptosis and ferroptosis markers, and these changes were obviously attenuated by P2X7 receptor knockdown. CONCLUSIONS P2X7 receptor-mediated functional pore formation by Beta1 toxin can further lead to calcium dyshomeostasis, thereby triggering excessive accumulation of ROS to subsequently induce the co-occurrence of pyroptosis and ferroptosis.
Animals ; Pyroptosis/drug effects* ; Receptors, Purinergic P2X7/metabolism* ; Mice ; Mice, Inbred BALB C ; Ferroptosis/drug effects* ; Humans ; Calcium/metabolism* ; Macrophages/drug effects* ; Bacterial Toxins/toxicity*

Aging involves the accumulation of various forms of molecular and cellular damage over time. Key features of aging, such as mitochondrial dysfunction, dysbiosis, and oxidative stress, are closely linked and largely driven by inflammation. This study examines the role of succinate, a key metabolite produced and utilized by cells of both host and microbes, and its receptor, succinate receptor 1 (SUCNR1), in age-related oral dysbiosis and inflammation. We examined young and aged wild-type (WT) and SUCNR1 knockout (KO) mice for this analysis. Our findings revealed significant aging-associated alveolar bone loss and succinate elevation in aged WT mice, along with notable changes in the oral microbiome. Conversely, aged KO mice showed reduced bone loss, lower succinate levels, less inflammation, and better-maintained microbial function. These results suggest that SUCNR1 is crucial in influencing aging-related succinate elevation, oral dysbiosis, and inflammation. Analysis of gene families and pathways in the oral microbiome demonstrated distinct aging-related changes between WT and KO mice, with the functional potential being preserved in the KO-aged group. This study underscores the importance of succinate elevation and signaling through SUCNR1 in regulating inflammation, alveolar bone loss, and shifts in the oral microbiome, offering potential targets for therapeutic interventions in age-related oral health issues.
Animals ; Dysbiosis/metabolism* ; Mice ; Succinic Acid/metabolism* ; Mice, Knockout ; Receptors, G-Protein-Coupled/metabolism* ; Inflammation/metabolism* ; Aging ; Alveolar Bone Loss/metabolism* ; Mouth/microbiology* ; Mice, Inbred C57BL ; Male ; Microbiota

OBJECTIVE: To investigate whether the G protein-coupled estrogen receptor (GPER) can attenuates acute lung injury in mice with exertional heat stroke (EHS) by inhibiting ferroptosis. METHODS: Sixty SPF-grade male C57BL/6 mice were randomly divided into four groups: normal control group (control group), EHS model group (EHS group), dimethyl sulfoxide (DMSO) solvent group (EHS+DMSO group), and GPER-specific agonist G1 group (EHS+G1 group), with 15 mice in each group. All mice underwent 14 days of adaptive training at 24-26 centigrade before modeling, and the EHS model was established using a high-temperature treadmill device. After successful modeling, the mice were allowed to cool naturally at room temperature. In the EHS+G1 group, 40 μg/kg of the GPER-specific agonist G1 was slowly injected intraperitoneally immediately after modeling. In the EHS+DMSO group, 40 μg/kg of DMSO was slowly injected intraperitoneally immediately after modeling. The control group received no treatment. Five hours after modeling, abdominal aortic blood was collected, and lung tissues were harvested after euthanasia. The lung coefficient was calculated to evaluate lung injury. Lung histopathological changes were observed under a light microscope after hematoxylin-eosin (HE) staining, and a lung histopathological score was assigned. Enzyme-linked immunosorbent assay (ELISA) was used to detect serum levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), malondialdehyde (MDA), and Fe²⁺ in lung tissue. Immunofluorescence was used to detect the expression of glutathione peroxidase 4 (GPX4). Real-time polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of GPX4, ferroportin 1 (FPN1), and ferritin heavy chain 1 (FTH1). Western blotting was performed to detect the protein expression of GPX4, FPN1, and FTH1. RESULTS: Compared with the control group, the lung coefficient and lung histopathological score were significantly increased in the EHS group. HE staining showed significant thickening and unevenness of the alveolar septa and alveolar walls, partial alveolar collapse, and extensive erythrocyte, inflammatory cell, and plasma-like material extravasation in the alveolar spaces. Serum levels of TNF-α, IL-1β, MDA, and Fe²⁺ were significantly elevated. Immunofluorescence staining showed a significant decrease in GPX4-positive expression in lung tissue. Western blotting and RT-PCR showed significantly reduced protein and mRNA expression of GPX4, FPN1, and FTH1 in lung tissue. Compared with the EHS group, the EHS+G1 group showed a significant reduction in lung coefficient and lung histopathological score [lung coefficient (mg/g): 3.9±0.1 vs. 4.6±0.3, lung histopathological score: 4.2±0.2 vs. 6.9±0.2, both P < 0.05]. HE staining revealed reduced severity of lung tissue fluid extravasation, inflammatory infiltration, decreased hemorrhage, and less severe alveolar structural damage. Serum levels of TNF-α, IL-1β, MDA, and Fe²⁺ were significantly reduced [TNF-α (ng/L): 44.3±0.2 vs. 64.6±0.3, IL-1β (ng/L): 69.3±0.4 vs. 97.8±0.2, MDA (nmol/L): 2.8±0.3 vs. 3.6±0.5, Fe²⁺ (nmol/L): 0.021±0.004 vs. 0.028±0.004, all P < 0.05]. Immunofluorescence staining showed a significant decrease in GPX4-positive expression in lung tissue (fluorescence intensity: 35.53±2.41 vs. 16.45±0.31, P < 0.05). RT-PCR and Western blotting showed significantly increased mRNA and protein expression of GPX4, FPN1, and FTH1 in lung tissue [mRNA expression: GPX4 mRNA (2^-ΔΔCt): 0.44±0.05 vs. 0.09±0.01, FPN1 mRNA (2^-ΔΔCt): 0.77±0.17 vs. 0.42±0.14, FTH1 mRNA (2^-ΔΔCt): 0.75±0.04 vs. 0.58±0.01; protein expression: GPX4/β-actin: 0.96±0.11 vs. 0.24±0.04, FPN1/β-actin: 1.26±0.21 vs. 0.44±0.14, FTH1/β-actin: 0.27±0.12 vs. 0.15±0.07; all P < 0.05]. However, there were no statistically significant differences in any of the above indicators between the EHS+DMSO group and the EHS group. CONCLUSION Activation of GPER can attenuate EHS-related lung injury in mice, and its mechanism may be related to the activation of the GPX4 signaling pathway and inhibition of ferroptosis.
Animals ; Mice, Inbred C57BL ; Male ; Mice ; Heat Stroke/metabolism* ; Receptors, G-Protein-Coupled ; Ferroptosis ; Receptors, Estrogen ; Acute Lung Injury/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-1beta/metabolism* ; Lung Injury ; Lung/metabolism*

In order to investigate whether the effect of Yuxuebi Tablets on the peripheral and central inflammation resolution of mice with inflammatory pain is related to their regulation of G protein-coupled receptor 37(GPR37), an inflammatory pain model was established by injecting complete Freund's adjuvant(CFA) into the paws of mice, with a sham-operated group receiving a similar volume of normal saline. The mice were assigned randomly to the sham-operated group, model group, ibuprofen group(91 mg·kg~(-1)), and low-, medium-, and high-dose groups of Yuxuebi Tablets(60, 120, and 240 mg·kg~(-1)). The drug was administered orally from days 1 to 19 after modeling. Von Frey method and the hot plate test were used to detect mechanical pain thresholds and heat hyperalgesia. The levels of interleukin-10(IL-10) and transforming growth factor-beta(TGF-β) in the spinal cord were quantified using enzyme-linked immunosorbent assay(ELISA), and the mRNA and protein expression of GPR37 in the spinal cord was measured by real-time quantitative reverse transcription PCR(qRT-PCR) and Western blot. Additionally, immunofluorescence was used to detect the expression of macrosialin antigen(CD68), mannose receptor(MRC1 or CD206), and GPR37 in dorsal root ganglia, as well as the expression of calcium-binding adapter molecule 1(IBA1), CD206, and GPR37 in the dorsal horn of the spinal cord. The results showed that compared with those of the sham-operated group, the mechanical pain thresholds and hot withdrawal latency of the model group significantly declined, and the expression of CD68 in the dorsal root ganglia and the expression of IBA1 in the dorsal horn of the spinal cord significantly increased. The expression of CD206 and GPR37 significantly decreased in the dorsal root ganglion and dorsal horn of the spinal cord, and IL-10 and TGF-β levels in the spinal cord were significantly decreased. Compared with those of the model group, the mechanical pain thresholds and hot withdrawal latency of the high-dose group of Yuxuebi Tablets significantly increased, and the expression of CD68 in the dorsal root ganglion and IBA1 in the dorsal horn of the spinal cord significantly decreased. The expression of CD206 and GPR37 in the dorsal root ganglion and dorsal horn of the spinal cord significantly increased, as well as IL-10 and TGF-β levels in the spinal cord. These findings indicated that Yuxuebi Tablets may reduce macrophage(microglial) infiltration and foster M2 macrophage polarization by enhancing GPR37 expression in the dorsal root ganglia and dorsal horn of the spinal cord of CFA-induced mice, so as to improve IL-10 and TGF-β levels, promote resolution of both peripheral and central inflammation, and play analgesic effects.
Inflammation/genetics* ; Pain/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Animals ; Mice ; Freund's Adjuvant/pharmacology* ; Ibuprofen ; Pain Threshold/drug effects* ; Hyperalgesia/genetics* ; Ganglia, Spinal ; Interleukin-10/genetics* ; Transforming Growth Factor beta/genetics* ; Reverse Transcriptase Polymerase Chain Reaction ; Tablets ; Receptors, G-Protein-Coupled

The quality of traditional Chinese medicine(TCM) is a critical foundation for ensuring the stability of its efficacy, as well as the safety and effectiveness of its clinical use. The identification of critical quality attributes(CQAs) is one of the core components of TCM preparation quality control. This study focuses on Jianwei Xiaoshi Tablets and explores their CQAs related to property and flavor from the perspective of taste receptor proteins. Three taste receptor proteins, T1R2, T1R3, and TRPV1, were selected, and a biosensor based on high-electron-mobility transistor(HEMT) was constructed to detect the interactions between Jianwei Xiaoshi Tablets and taste receptor proteins. Simultaneously, liquid chromatography-mass spectrometry(LC-MS) technology was used to analyze the chemical composition of Jianwei Xiaoshi Tablets. In examining the interaction strength, the results indicated that the interaction between Jianwei Xiaoshi Tablets and TRPV1 protein was the strongest, followed by T1R3, with the interaction with T1R2 being relatively weaker. By combining biosensing technology with LC-MS, 16 chemical components were identified from Jianwei Xiaoshi Tablets, among which six were selected as CQAs for sweetness and seven for pungency. Further validation experiments demonstrated that CQAs such as hesperidin and hesperetin had strong interactions with their corresponding taste receptor proteins. Through the combined use of multiple technological approaches, this study successfully determined the property and flavor-related CQAs of Jianwei Xiaoshi Tablets. It provides novel ideas and approach for the identification of CQAs in TCM preparations and offers comprehensive theoretical support for TCM quality control, contributing to the improvement and development of TCM preparation quality control systems.
Drugs, Chinese Herbal/chemistry* ; Biosensing Techniques/methods* ; TRPV Cation Channels/chemistry* ; Tablets/chemistry* ; Receptors, G-Protein-Coupled/genetics* ; Quality Control ; Taste ; Humans ; Mass Spectrometry

Objective This study aims to investigate the effect of berberine (Ber) on foam cell formation induced by oxidized low-density lipoprotein (ox-LDL) in macrophages and to explore the mechanism's association with the ACE2-Ang(1-7)-Mas axis. Methods They were randomly divided into blank group, model group (RAW264.7 cells induced with 60 μg/mL ox-LDL), and berberine group (the model treated with berberine interventions at 2.5, 5, and 10 μmol/L concentrations). Lipid accumulation within the cells was assessed by Oil Red O staining, and the content of lipid droplets in each group was quantitatively analyzed by enzymatic method. The content of total cholesterol (TC) and free cholesterol (FC) in foam cells were detected by enzymatic method. The levels of oxidative stress factors (malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH)), inflammatory factors such as tumor necrosis factor α(TNF-α), and nitric oxide (NO) were measured using corresponding relevant reagent kits. The mRNA and protein expressions of ACE2 and Mas were evaluated through quantitative real-time PCR and Western blot analysis, respectively. The levels of AngII and Ang(1-7) were detected by ELISA. Results Compared with the model group, the berberine groups exhibited reduced lipid droplet accumulation and a dose-dependent decrease in intracellular lipid content. Berberine significantly lowered TC and FC levels in foam cells and reduced the CE/TC ratio. The levels of the oxidative factor MDA were significantly reduced, while the levels of the antioxidant factors SOD and GSH were markedly increased. Inflammatory factors TNF-α and NO were significantly decreased. The expression of the ACE2-Ang(1-7)-Mas signaling pathway was significantly activated, and the effect was more pronounced in the Ber group with high-concentration compared to the group with low-concentration, demonstrating a dose-dependent response. Conclusion Berberine can inhibit macrophage foam cell formation, potentially through upregulation of the ACE2-Ang(1-7)-Mas signaling pathway, thereby contributing to the alleviation of atherosclerosis.
Berberine/pharmacology* ; Foam Cells/cytology* ; Animals ; Signal Transduction/drug effects* ; Mice ; Angiotensin-Converting Enzyme 2 ; Angiotensin I/genetics* ; Peptidyl-Dipeptidase A/genetics* ; Peptide Fragments/genetics* ; Receptors, G-Protein-Coupled/genetics* ; RAW 264.7 Cells ; Proto-Oncogene Proteins/genetics* ; Proto-Oncogene Mas ; Lipoproteins, LDL/pharmacology* ; Nitric Oxide/metabolism* ; Tumor Necrosis Factor-alpha/metabolism*