1.Alamandine inhibits pathological retinal neovascularization by targeting the MrgD-mediated HIF-1α/VEGF pathway.
Kun ZHAO ; Yaping JIANG ; Wen HUANG ; Yukang MAO ; Yihui CHEN ; Peng LI ; Chuanxi YANG
Journal of Zhejiang University. Science. B 2025;26(10):1015-1036
Retinopathy of prematurity (ROP) is a vision-threatening disorder that leads to pathological growth of the retinal vasculature due to hypoxia. Here, we investigated the potential effects of alamandine, a novel heptapeptide in the renin-angiotensin system (RAS), on hypoxia-induced retinal neovascularization and its underlying mechanisms. In vivo, the C57BL/6J mice with oxygen-induced retinopathy (OIR) were injected intravitreally with alamandine (1.0 μmol/kg per eye). In vitro, human retinal microvascular endothelial cells (HRMECs) were utilized to investigate the effects of alamandine (10 μg/mL) on proliferation, apoptosis, migration, and tubular formation under vascular endothelial growth factor (VEGF) stimulation. Single-cell RNA sequencing (scRNA-seq) matrix data from the Gene Expression Omnibus (GEO) database and RAS-related genes from the Molecular Signatures Database (MSigDB) were sourced for subsequent analyses. By integrating scRNA-seq data across multiple species, we identified that RAS-associated endothelial cell populations were highly related to retinal neovascularization. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis revealed a significant decrease in alamandine levels in both the serum and retina of OIR mice compared to those in the control group. Next, alamandine ameliorated hypoxia-induced retinal pathological neovascularization and physiologic revascularization in OIR mice. In vitro, alamandine effectively mitigated VEGF-induced proliferation, scratch wound healing, and tube formation of HRMECs primarily by inhibiting the hypoxia-inducible factor-1α (HIF-1α)/VEGF pathway. Further, coincubation with D-Pro7 (Mas-related G protein-coupled receptor D (MrgD) antagonist) hindered the beneficial impacts of alamandine on hypoxia-induced pathological angiogenesis both in vivo and in vitro. Our findings suggested that alamandine could mitigate retinal neovascularization by targeting the MrgD-mediated HIF-1α/VEGF pathway, providing a potential therapeutic agent for OIR prevention and treatment.
Animals
;
Retinal Neovascularization/prevention & control*
;
Mice, Inbred C57BL
;
Vascular Endothelial Growth Factor A/metabolism*
;
Humans
;
Mice
;
Hypoxia-Inducible Factor 1, alpha Subunit/metabolism*
;
Oligopeptides/therapeutic use*
;
Signal Transduction/drug effects*
;
Cell Proliferation/drug effects*
;
Endothelial Cells/drug effects*
;
Retinopathy of Prematurity/drug therapy*
;
Apoptosis/drug effects*
;
Cell Movement/drug effects*
;
Renin-Angiotensin System/drug effects*
;
Cells, Cultured
2.Schistosoma japonicum cystatin has protective effects against "two-hit" sepsis in mice by regulating the inflammatory microenvironment.
Wenjuan DUO ; Yixiang WANG ; Jiaxing WANG ; Xinlong XU ; Linxian LI ; Dongchen YANG ; Qili SHEN ; Lichun YANG ; Xiaojing LIU ; Qiwang JING ; Liang CHU ; Xiaodi YANG
Journal of Southern Medical University 2025;45(1):110-117
OBJECTIVES:
To evaluate the protective effect of Schistosoma japonicum cystatin (rSj-Cystatin) in a mouse mode of "two-hit" sepsis.
METHODS:
Sixty male C57BL/6 mice randomized equally into sham-operated group, protein group, "two-hit" modeling group, and protein intervention group. In the former two groups, the mice received an intraperitoneal injection of 100 μL PBS followed by exposure of the cecum and then by intraperitoneal injection of 100 μL PBS or 25 μg rSj-Cystatin 30 min later; In the latter two groups, 100 μL PBS containing LPS (5 mg/kg) was injected intraperitoneally 24 h before cecal ligation and puncture (CLP), and 100 μL PBS or 25 μg rSj-Cystatin were injected 30 min after CLP. At 12 h after rSj-Cystatin treatment, 6 mice from each group were sacrificed for detection of TNF-α, IL-6, IL-10, TGF-β, iNOS and Arg-1 in the serum, spleen, liver, lung and kidney tissues using ELISA, for examinations of liver, lung and kidney pathologies with HE staining, and for analysis of CD3+CD4+CD25+Foxp3+ T cell percentage in the spleen using flow cytometry. The remaining mice were observed for general condition and 72-h survival.
RESULTS:
The 72-h survival rates in the 4 groups were 100%, 100%, 0% and 20%, respectively, showing significant differences between the latter two groups. The mouse models of "two-hit" sepsis exhibited obvious tissue pathologies and significant elevations of TNF-α and IL-6 in both the serum and tissue homogenate, which were significantly ameliorated by rSj-Cystatin treatment. Treatment with rSj-Cystatin also increased IL-10 and TGF-β levels and spleen CD3+CD4+CD25+Foxp3+ T cell percentage. The septic mouse models also showed increased iNOS levels in all the detected tissues and a decreased Arg-1 level in the kidney, and these changes were obviously improved by rSj-Cystatin treatment.
CONCLUSIONS
rSj-Cystatin has a protective effect against "two-hit" sepsis in mice by regulating the inflammatory microenvironment.
Animals
;
Mice
;
Sepsis/drug therapy*
;
Male
;
Schistosoma japonicum/chemistry*
;
Mice, Inbred C57BL
;
Cystatins/therapeutic use*
;
Interleukin-10/metabolism*
;
Interleukin-6/blood*
;
Tumor Necrosis Factor-alpha/blood*
;
Disease Models, Animal
;
Transforming Growth Factor beta/metabolism*
3.NLRP6 overexpression improves nonalcoholic fatty liver disease by promoting lipid oxidation and decomposition in hepatocytes through the AMPK/CPT1A/PGC1A pathway.
Qing SHI ; Suye RAN ; Lingyu SONG ; Hong YANG ; Wenjuan WANG ; Hanlin LIU ; Qi LIU
Journal of Southern Medical University 2025;45(1):118-125
OBJECTIVES:
To investigate the regulatory role of nucleotide-bound oligomerized domain-like receptor containing pyrin-domain protein 6 (NLRP6) in liver lipid metabolism and non-alcoholic fatty liver disease (NAFLD).
METHODS:
Mouse models with high-fat diet (HFD) feeding for 16 weeks (n=6) or with methionine choline-deficient diet (MCD) feeding for 8 weeks (n=6) were examined for the development of NAFLD using HE and oil red O staining, and hepatic expressions of NLRP6 were detected with RT-qPCR, Western blotting, and immunohistochemical staining. Cultured human hepatocytes (LO2 cells) with adenovirus-mediated NLRP6 overexpression or knock-down were treated with palmitic acid (PA) in the presence or absence of compound C (an AMPK inhibitor), and the changes in cellular lipid metabolism were examined by measuring triglyceride, ATP and β-hydroxybutyrate levels and using oil red staining, RT-qPCR, and Western blotting.
RESULTS:
HFD and MCD feeding both resulted in the development of NAFLD in mice, which showed significantly decreased NLRP6 expression in the liver. In PA-treated LO2 cells, NLRP6 overexpression significantly decreased cellular TG content and lipid deposition, while NLRP6 knockdown caused the opposite effects. NLRP6 overexpression in PA-treated LO2 cells also increased mRNA and protein expressions of PGC1A and CPT1A, levels of ATP and β-hydroxybutyrate, and the phosphorylation level of AMPK pathway; the oxidative decomposition of lipids induced by Ad-NLRP6 was inhibited by the use of AMPK inhibitors.
CONCLUSIONS
NLRP6 overexpression promotes lipid oxidation and decomposition through AMPK/CPT1A/PGC1A to alleviate lipid deposition in hepatocytes.
Non-alcoholic Fatty Liver Disease/metabolism*
;
Animals
;
Hepatocytes/metabolism*
;
Lipid Metabolism
;
Mice
;
Humans
;
Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
;
AMP-Activated Protein Kinases/metabolism*
;
Carnitine O-Palmitoyltransferase/metabolism*
;
Diet, High-Fat
;
Male
;
Mice, Inbred C57BL
;
Signal Transduction
4.Prevotella nigrescens exacerbates periodontal inflammation and impairs cognitive function in mice.
Qi CHEN ; Tiantian XIA ; Yongqiang ZHOU ; Mingyang CHANG ; Nan HU ; Yanmei YANG ; Zhong LI ; Yue GAO ; Bin GU
Journal of Southern Medical University 2025;45(3):453-460
OBJECTIVES:
To investigate the effects of periodontitis induced by Prevotella nigrescens (Pn) combined with ligation on cognitive functions in mice.
METHODS:
Twenty-four C57BL/6J mice were randomly divided into control group, ligation group, and ligation + Pn treatment (P+Pn) group. Experimental periodontitis was induced by silk ligation of the first molars followed by topical application of Pn for 6 weeks. After modeling, alveolar bone resorption was assessed using micro-CT and histological analysis. Learning and memory abilities of the mice were evaluated using open field test (OFT), novel object recognition test (NORT), and Morris water maze test (MWM). Seven weeks after the start of modeling, the mice were sacrificed for examining histopathological changes in the hippocampus using HE and Nissl staining.
RESULTS:
After 6 weeks of molar ligation, micro-CT revealed horizontal alveolar bone resorption and furcation exposure in the mice, and histological analysis showed apical migration of the junctional epithelium, epithelial ridge hyperplasia, and lymphocyte infiltration, and these changes were obviously worsened in P+Pn group. Alveolar bone height decreased significantly in both ligation groups compared to the control group. Cognitive tests showed that the mice in both of the ligation groups traveled shorter distances in OFT, showed reduced novel object preference in NORT, and exhibited longer escape latencies in MWM, and the mice in P+Pn group had significantly poorer performances in the tests. Histologically, obvious neuronal cytoplasmic degeneration, necrosis, nuclear pyknosis, vacuolation, and reduced Nissl bodies and viable neurons were observed in the hippocampal regions of the mice in the two ligation groups.
CONCLUSIONS
Pn infection aggravates alveolar bone destruction, accelerates necrosis and causes morphological abnormalities of neuronal cells in the hippocampus to reduce cognitive functions of mice with periodontitis.
Animals
;
Periodontitis/microbiology*
;
Mice
;
Mice, Inbred C57BL
;
Cognition
;
Alveolar Bone Loss
;
Hippocampus/pathology*
;
Male
;
Inflammation
;
Maze Learning
5.Hypericin ameliorates stress-induced depressive-like behaviors in mice by modulating the CN-NFAT calcium signaling pathway in microglia.
Zhengtao GAO ; Pingyan LIN ; Bingcan ZHOU ; Mingheng CHEN ; Erqi LIU ; Tianxiang LEI ; Huixin NI ; Haixin LIU ; Yao LIN ; Qian XU
Journal of Southern Medical University 2025;45(3):506-513
OBJECTIVES:
To investigate the role of the calcium/calmodulin (CaM)-mediated activation of calcineurin (CN)-nuclear factor of activated T cells (NFAT) signaling pathway in mediating the regulatory effect of hyperforin (HY) on stress-induced depression-like disorder (DP) in mice.
METHODS:
C57BL/6J mice were randomly divided into control group, DP model group, and hyperforin treatment group (n=15). Behavioral changes of the mice were assessed using open field test (OFT), sucrose preference test (SPT), tail suspension test (TST), light/dark box test (LDB), and novel object suppression test (NSFT). Immunohistochemistry was used to detect tyrosine hydroxylase (TH) expression in the CA1 region of the hippocampus, and serum serotonin (5-HT) and norepinephrine (NA) levels were detected with ELISA. Western blotting was used to analyze the expressions of TNF-α, IL-1β, IL-2, and CN-NFAT pathway proteins. In cultured BV-2 microglial cells with lipopolysaccharide (LPS) stimulation, the effects of hyperforin and CN inhibitor (CNIS) on expressions of ionized calcium-binding adapter molecule 1 (IBA-1), 5-HT, NA, inflammatory cytokines and CN-NFAT pathway proteins were examined using immunofluorescence assay, ELISA or Western blotting.
RESULTS:
Compared with the control mice, the mice in DP group showed significantly reduced activity in OFT, decreased sucrose consumption in SPT, reduced shuttle crossing in LDB, and lowered food intake in NSFT with significantly increased immobility in TST. The mice with DP showed significantly decreased TH-positive neurons, lowered 5-HT and NA levels, and increased expressions of TNF-α, IL-1β, IL-2 and CaM-CN-NFAT pathway proteins. In cultured BV-2 cells, LPS stimulation strongly increased cellular IBA-1 expression, decreased the levels of neurotransmitters (5-HT and NA), and increased the levels of inflammatory cytokines and CN-NFAT signaling, and these changes were effectively reversed by treatment with hyperforin or CNIS.
CONCLUSIONS
Hyperforin improves stress-induced depression-like behaviors in mice and activated BV-2 cells by targeting the CN-NFAT signaling pathway.
Animals
;
Mice, Inbred C57BL
;
Mice
;
Microglia/drug effects*
;
Depression/etiology*
;
Perylene/pharmacology*
;
Calcineurin/metabolism*
;
NFATC Transcription Factors/metabolism*
;
Calcium Signaling/drug effects*
;
Stress, Psychological
;
Phloroglucinol/pharmacology*
;
Signal Transduction
;
Male
;
Behavior, Animal/drug effects*
;
Terpenes
6.Protective effect of graphene heating film far-infrared hyperthermia against frostbite in mice.
Jinshui ZHANG ; Shuo LI ; Dongdong WEI ; Xin CHENG ; Yun DENG ; Youzhi ZHANG
Journal of Southern Medical University 2025;45(3):522-530
OBJECTIVES:
To investigate the protective effects of graphene heating film far-infrared (FIR) hyperthermia therapy against frostbite in mice and its impacts on microcirculation and coagulation function.
METHODS:
Seventy-six C57BL/6J mice were randomized into control, model, graphene-FIR, and carbon fiber-FIR groups. After 7-day FIR intervention (4 h/day), the mice were subjected to acute (4 ℃, 4 h) and intermittent (4 ℃, 4 h/day for 3 days) cold exposure and the changes in rectal temperature were monitored. In liquid nitrogen frostbite experiment, 24 ICR mice were divided into model, graphene-FIR, and carbon fiber-FIR groups, and after a 7-day FIR pretreatment (4 h/day), the liquid nitrogen frostbite models were established and apparent scores of the wounds were assessed on days 3 and 6 after modeling. In carrageenan-induced thrombosis experiment, 40 ICR mice were allocated to control, model, graphene-FIR, carbon fiber-FIR, and prazosin groups to test the effect of a 7-day FIR intervention on thrombosis induced by intraperitoneal carrageenan injection (2.5 mg/kg) by measuring thrombus length, blood perfusion, and serum biomarkers (6-keto-PGF1α, TXB2, t-PA, IL-6, IL-1β, TNF‑α) 24 h after the injection.
RESULTS:
The mice in graphene-FIR group showed significantly elevated rectal temperature in cold exposure tests. In mice with liquid nitrogen-induced frostbite, graphene-FIR treatment significantly reduced the wound scores and reduced frostbite area, producing better effects than carbon fiber. In mice with carrageenan-induced thrombosis, graphene-FIR treatment significantly decreased tail thrombosis length and thrombosis area, increased blood perfusion, lowered serum levels of TXB2, TNF-α and IL-6, and increased the levels of 6-keto-PGF1α and t-PA.
CONCLUSIONS
Graphene heating film FIR therapy can alleviate frostbite injury in mice by improving microcirculation, suppressing thrombosis and inflammatory responses, and reducing coagulation dysfunction.
Animals
;
Frostbite/therapy*
;
Graphite
;
Mice, Inbred C57BL
;
Mice
;
Infrared Rays
;
Mice, Inbred ICR
;
Hyperthermia, Induced/methods*
;
Male
;
Microcirculation
7.Therapeutic effects of inulin-type oligosaccharides of Morinda officinalis on Streptococcus pneumoniae meningitis in mice.
Zehan LI ; Meng LIANG ; Gencheng HAN ; Xuewu ZHANG
Journal of Southern Medical University 2025;45(3):577-586
OBJECTIVES:
To investigate the therapeutic effects of inulin-type oligosaccharides of Morinda officinalis (IOMO) in a murine model of Streptococcus pneumoniae meningitis (SPM) and explore its possible mechanisms.
METHODS:
A total of 120 male C57BL/6J mice were randomly assigned into Sham, SPM+Saline, SPM+IOMO (25 mg/kg), and SPM+IOMO (50 mg/kg) groups. After modeling, the mice received daily gavage of saline or IOMO at the indicated doses for 7 consecutive days, and the changes in symptom scores and mortality of the mice were monitored. Brain pathology and neuronal injury of the mice were assessed using HE and Nissl staining, and qRT-PCR was performed to detect mRNA levels of the inflammatory mediators. Brain edema and blood-brain barrier (BBB) permeability of the mice were evaluated by measuring brain water content and Evans blue (EB) staining; Western blotting was used to analyze the expressions of BBB-associated proteins, and flow cytometry was employed to detect IFN‑γ expression level in the infiltrating lymphocytes. Open-field test (OFT) and novel object recognition test (NORT) were conducted to assess learning and memory ability of the mice on day 21 after modeling.
RESULTS:
IOMO treatment at 50 mg/kg significantly reduced the symptom scores and mortality rate of SPM mice, alleviated brain damage, and downregulated mRNA levels of IL-6, TNF‑α, IL-1β, IL-18, IFN‑γ, iNOS, NLRP3, ASC, caspase-1 and GSDMD in the brain tissue. IOMO treatment also decreased brain water content and EB leakage, upregulated VE-cadherin and occludin expressions, and suppressed AQP4, iNOS, and IFN‑γ levels of the mice. IOMO-treated mice exhibited improved learning and memory compared with the saline-treated mice on day 21 after SPM modeling.
CONCLUSIONS
IOMO alleviates SPM symptoms, reduces mortality, and mitigates cognitive deficits in mice possibly by suppressing cerebral inflammation and protecting BBB functions.
Animals
;
Morinda/chemistry*
;
Mice, Inbred C57BL
;
Male
;
Mice
;
Meningitis, Pneumococcal/drug therapy*
;
Blood-Brain Barrier/metabolism*
;
Inulin/therapeutic use*
;
Oligosaccharides/therapeutic use*
;
Disease Models, Animal
;
Interferon-gamma/metabolism*
;
Brain Edema
8.Cimifugin ameliorates Crohn's disease-like colitis in mice by modulating Th-cell immune balance via inhibiting the MAPK pathway.
Lixia YIN ; Minzhu NIU ; Keni ZHANG ; Zhijun GENG ; Jianguo HU ; Jiangyan LI ; Jing LI
Journal of Southern Medical University 2025;45(3):595-602
OBJECTIVES:
To investigate the therapeutic effects of cimifugin on Crohn's disease (CD)-like colitis in mice and its possible mechanism.
METHODS:
Thirty adult male C57BL/6 mice were randomized equally into control group, 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced CD-like colitis model group, and cimifugin treatment (daily gavage at 12.5 mg/kg) group. The therapeutic effect of cimifugin was evaluated by observing changes in body weight, disease activity index (DAI) scores, colon length, histopathological inflammation scores, and inflammatory cytokine levels in the colonic mucosa. Intestinal barrier integrity in the mice was assessed using immunofluorescence assay and Western blotting for claudin-1 and ZO-1; T-helper (Th) cell subset ratios in the mesenteric lymph nodes were analyzed with flow cytometry. Network pharmacology, KEGG enrichment analysis and molecular docking were used to predict the targets of cimifugin and analyze the key pathways and cimifugin-MAPK protein interactions, which were validated by Western blotting in the mouse models.
RESULTS:
In mice with TNBS-induced colitis, cimifugin treatment significantly attenuated body weight loss and colon shortening, lowered DAI and histopathological scores, decreased IFN-γ and IL-17 levels, and increased IL-4 and IL-10 levels in the colonic mucosa. Cimifugin treatment also significantly improved TNBS-induced claudin-1 dislocation and reduction of goblet cells, upregulated claudin-1 and ZO-1 expressions, reduced Th1 and Th17 cell percentages, and increased Th2 and Treg cell percentages in the colonic mucosa of the mice. KEGG analysis suggested a possible connection between the effect of cimifugin and MAPK signaling, and molecular docking showed strong binding affinity between cimifugin and MAPK core proteins. Western blotting demonstrated significantly decreased phosphorylation levels of JNK, ERK, and p38 in the colonic mucosa of cimifugin-treated mouse models.
CONCLUSIONS
Cimifugin alleviates TNBS-induced CD-like colitis by repairing intestinal barrier damage and restoring Th1/Th2 and Th17/Treg balance via suppressing MAPK pathway activation.
Animals
;
Mice, Inbred C57BL
;
Male
;
Mice
;
Crohn Disease/immunology*
;
Colitis/immunology*
;
MAP Kinase Signaling System/drug effects*
;
Trinitrobenzenesulfonic Acid
;
T-Lymphocytes, Helper-Inducer/drug effects*
;
Intestinal Mucosa
;
Disease Models, Animal
9.Effects of liver fibrosis induced by iron overload on M2 polarization of macrophages in mice.
Jiawen YU ; Yi ZHOU ; Chunmei QIAN ; Lan MU ; Renye QUE
Journal of Southern Medical University 2025;45(4):684-691
OBJECTIVES:
To observe the evolution of intrahepatic macrophage polarization in mice with liver fibrosis induced by iron overload.
METHODS:
Thirty-two C57BL/6 mice (6-8 weeks) were randomized into control group (n=8) and liver fibrosis model group (n=24) induced by aidly intraperitoneal injection of iron dextran. At the 3rd, 5th, and 7th weeks of modeling, 8 mice in the model group were sacrificed for observing liver fibrosis using Masson, Sirius Red and immunohistochemical staining and detecting serum levels of ALT, AST and the levels of serum iron, ferritin, liver total Fe and ferrous Fe. iNOS+/F4/80+ cells and CD206+/F4/80+ cells were detected by double immunofluorescence assay to observe the proportion and distribution of M1 and M2 macrophages. The hepatic expressions of Arg-1, iNOS, IL-6, IL-10, and TNF‑α proteins were detected using Western blotting or ELISA, and the expression of CD206 mRNA was detected using RT-PCR.
RESULTS:
The mice in the model group showed gradual increase of fibrous tissue hyperplasia in the portal area over time, structural destruction of the hepatic lobules and formation of pseudolobules. With the passage of time during modeling, the rat models showed significantly increased hepatic expressions of α-SMA and COL-1, elevated serum levels of ALT, AST, Fe, ferritin, and increased liver total Fe and ferrous Fe levels. The expressions of M1 polarization markers IL-6, TNF‑α, and iNOS all increased with time and reached their peak levels at the 3rd week; The expressions of M2 polarization markers (IL-10 and Arg-1 proteins and CD206 mRNA) significantly increased in the 3rd week and but decreased in the 5th and 7th weeks.
CONCLUSIONS
Iron overload promotes M1 polarization of macrophages in mice. Liver fibrosis in the early stage promotes M2 polarization of macrophages but negatively regulate M2 polarization at later stages.
Animals
;
Mice
;
Mice, Inbred C57BL
;
Iron Overload/pathology*
;
Macrophages/metabolism*
;
Male
;
Liver Cirrhosis/etiology*
;
Nitric Oxide Synthase Type II/metabolism*
;
Interleukin-10/metabolism*
;
Liver/pathology*
;
Interleukin-6/metabolism*
;
Mannose Receptor
;
Tumor Necrosis Factor-alpha/metabolism*
;
Mannose-Binding Lectins/metabolism*
;
Arginase
10.Activation of astrocytes in the dorsomedial hypothalamus accelerates sevoflurane anesthesia emergence in mice.
Shuting GUO ; Fuyang CAO ; Yongxin GUO ; Yanxiang LI ; Xinyu HAO ; Zhuoning ZHANG ; Zhikang ZHOU ; Li TONG ; Jiangbei CAO
Journal of Southern Medical University 2025;45(4):751-759
OBJECTIVES:
To investigate the regulatory role of astrocytes in the dorsomedial hypothalamus (DMH) during sevoflurane anesthesia emergence.
METHODS:
Forty-two male C57BL/6 mice were randomized into 6 groups (n=7) for assessing astrocyte activation in the dorsomedial hypothalamus (DMH) under sevoflurane anesthesia. Two groups of mice received microinjection of agfaABC1D promoter-driven AAV2 vector into the DMH for GCaMP6 overexpression, and the changes in astrocyte activity during sevoflurane or air inhalation were recorded using calcium imaging. For assessing optogenetic activation of astrocytes, another two groups of mice received microinjection of an optogenetic virus or a control vector into the DMH with optic fiber implantation, and sevoflurane anesthesia emergence was compared using behavioral experiments. In the remaining two groups, electroencephalogram (EEG) recording during sevoflurane anesthesia emergence was conducted after injection of the hChR2-expressing and control vectors. Anesthesia induction and recovery were assessed by observing the righting reflex. EEG data were recorded under 2.0% sevoflurane to calculate the burst suppression ratio (BSR) and under 1.5% sevoflurane for power spectrum analysis. Immunofluorescence staining was performed to visualize the colocalization of GFAP-positive astrocytes with viral protein signals.
RESULTS:
Astrocyte activity in the DMH decreased progressively as sevoflurane concentration increased. During 2.0% sevoflurane anesthesia, the mice injected with the ChR2-expressing virus exhibited a significantly shortened wake-up time (P<0.05), and optogenetic activation of the DMH astrocytes led to a marked reduction in BSR (P<0.001). Under 1.5% sevoflurane anesthesia, optogenetic activation resulted in a significant increase in EEG gamma power and a significant decrease in delta power in ChR2 group (P<0.01).
CONCLUSIONS
Optogenetic activation of DMH astrocytes facilitates sevoflurane anesthesia emergence but does not significantly influence anesthesia induction. These findings offer new insights into the mechanisms underlying anesthesia emergence and may provide a potential target for accelerating postoperative recovery and managing anesthesia-related complications.
Animals
;
Astrocytes/physiology*
;
Sevoflurane
;
Mice, Inbred C57BL
;
Mice
;
Male
;
Electroencephalography
;
Anesthetics, Inhalation/pharmacology*
;
Hypothalamus/cytology*
;
Anesthesia Recovery Period
;
Methyl Ethers/pharmacology*

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