OBJECTIVE: To observe the effects of Tongdu Tiaoshen acupuncture (acupuncture for unblocking the obstruction in the governor vessel and regulating the spirit) on the depression-like behavior and the hippocampal neuronal ferroptosis mediated by solute carrier family 7 member 11 (SLC7A11)/glutathione peroxidase 4 (GPX4) pathway in depression rats, and explore the mechanism of this therapy for depression. METHODS: Of 30 male SD rats of SPF grade, 24 rats were selected. According to the random number table, they were divided into a normal group (n=8) and a modeling group (n=16). The rats in the modeling group were subjected to chronic unpredictable mild stress (CUMS) for 28 consecutive days to establish depression model. After modeling, 16 successfully-modeled rats were randomly divided into a model group and an acupuncture group, 8 rats in each one. In the acupuncture group, Tongdu Tiaoshen acupuncture was applied to "Dazhui"(GV14), "Shuigou" (GV26), "Baihui" (GV20) and "Shenting" (GV24). This intervention measure was deliveredonce a day, continuously for 6 days. The intervention discontinued on day 7, and was completed in 4 weeks. Before and after modeling, and after intervention completion, the behavioristics detection was performed using sucrose preference experiment and open field experiment. After intervention, using hematoxylin-eosin (HE) and Nissl staining, the morphology of hippocampal neurons was observed; with Western blot method, the protein expression of GPX4, SLC7A11, Ferritin and acyl-CoA synthetase long-chain family 4 (ACSL4) in hippocampal tissues was detected; with the real-time fluorescence quantitative PCR adopted, the mRNA expression of GPX4, SLC7A11, Ferritin and ACSL4 was detected; and using colorimetry, the hippocampal iron content was determined. RESULTS: After modeling, the sucrose preference rates, the total distance of movement, the standing times and the boxes of horizontal crossing in the model group and the acupuncture group were lower than those in the normal group (P<0.01). After the intervention, the sucrose preference rates, the total distance of movement, the standing times and the boxes of horizontal crossing in the acupuncture group were higher than those in the model group (P<0.01, P<0.05). Compared with the normal group, the number of necrotic cells increased and the number of Nissl bodies decreased in the model group; and when compared with the model group, the neuronal pyknosis and necrosis were ameliorated, the cells were arranged more regularly, the neuronal structure was clear, the matrix was dense, the blood vessels were enriched and the number of Nissl bodies increased in the acupuncture group. In comparison with the normal group, the relative expression of protein and mRNA of hippocampal GPX4, SLC7A11 decreased (P<0.01), it increased in the expression of hippocampal Ferritin and ACSL4 (P<0.01) in the model group. When compared with the model group, in the acupuncture group, the relative expression of protein and mRNA of hippocampal GPX4, SLC7A11 was elevated (P<0.01, P<0.05), it was dropped for hippocampal Ferritin and ACSL4 (P<0.01). In the model group, the hippocampal iron content was elevated when compared with that in the normal group (P<0.01); and it was reduced in the acupuncture group when compared with that in the model group (P<0.05). CONCLUSION Tongdu Tiaoshen acupuncture attenuates depression-like behaviors in the depression rats, which may be related to regulating SLC7A11/GPX4 pathway and inhibiting neuronal ferroptosis in the hippocampus.
Animals ; Ferroptosis ; Male ; Hippocampus/cytology* ; Rats, Sprague-Dawley ; Rats ; Depression/enzymology* ; Phospholipid Hydroperoxide Glutathione Peroxidase/genetics* ; Acupuncture Therapy ; Neurons/metabolism* ; Humans ; Acupuncture Points ; Amino Acid Transport System y+/genetics* ; Glutathione Peroxidase/genetics*

OBJECTIVE: To observe the effect of Huayu Tongluo moxibustion on the NOD-like receptor protein 3 (NLRP3)/cysteine-aspartic acid protease-1 (Caspase-1)/gasdermin D (GSDMD) signaling pathway in rats with vascular dementia (VD), and to explore its mechanism in improving learning and memory ability and alleviating neuronal injury in the hippocampal CA1 region. METHODS: A total of 80 SPF-grade male Wistar rats were included. Three rats were excluded based on the Morris water maze test. From the remaining rats, 12 were randomly selected as the sham operation group. The rest were used to establish VD models via modified bilateral common carotid artery ligation. Thirty-six successfully modeled rats were randomly divided into a model group, a medication group, and a moxibustion group, with 12 rats in each group. The medication group was treated with nimodipine solution (12 mg/kg) via gavage. The moxibustion group was treated with Huayu Tongluo moxibustion. The suspended moxibustion was applied at Shenting (GV24) and Dazhui (GV14), and aconite cake-separated moxibustion was applied at Baihui (GV20), with each acupoint treated for 20 min. All treatments were administered once daily for 21 consecutive days. Before and after modeling, and after intervention, the Morris water maze test was used to assess cognitive function. After intervention, the activation and morphology of microglia in the hippocampal CA1 region were observed by immunofluorescence. Ultrastructure of hippocampal CA1 neurons was examined by transmission electron microscopy. Western blot was used to detect protein expression of NLRP3, apoptosis-associated speck-like protein (ASC), Caspase-1, GSDMD, and interleukin-1β (IL-1β) in the hippocampal CA1 region. ELISA was used to detect the content of IL-6, IL-8, and tumor necrosis factor-α (TNF-α) in the hippocampal CA1 region. RESULTS: Compared with the sham operation group, the model group showed longer mean escape latency (P<0.01) and fewer platform crossings (P<0.01); the microglial processes in the hippocampal CA1 region were thickened, cytoplasm was hypertrophic, and relative fluorescence intensity of ionized calcium-binding adapter molecule 1 (IBA-1) was increased (P<0.05); the neuronal ultrastructure in the CA1 region was severely damaged, rough endoplasmic reticulum was swollen, mitochondria were deformed and swollen, some cristae were ruptured or dissolved, showing vacuolar changes; the protein expression of NLRP3, ASC, Caspase-1, GSDMD, and IL-1β, as well as levels of IL-6, IL-8, and TNF-α were significantly elevated (P<0.001). Compared with the model group, both the medication group and the moxibustion group showed shortened mean escape latency (P<0.01) and increased platform crossings (P<0.01); the microglial processes were thinner, and IBA-1 fluorescence intensity was decreased (P<0.05); the neuronal ultrastructure in the CA1 region was partially improved; the protein expression of NLRP3, ASC, Caspase-1, GSDMD, and IL-1β, and levels of IL-6, IL-8, and TNF-α were significantly reduced (P<0.001). Compared with the medication group, the moxibustion group showed shortened mean escape latency (P<0.05) and more platform crossings (P<0.05); the IBA-1 fluorescence intensity was decreased (P<0.05); the neuronal ultrastructure in the CA1 region was improved; the protein expression of NLRP3, ASC, Caspase-1, GSDMD, and IL-1β, as well as levels of IL-6, IL-8, and TNF-α, were significantly lower (P<0.001). CONCLUSION The Huayu Tongluo moxibustion could enhance learning and memory abilities in VD rats, inhibit excessive activation of microglia, and alleviate neuronal injury in the hippocampal CA1 region. Its mechanism may involve modulation of the NLRP3/Caspase-1/GSDMD signaling pathway, reduction of inflammatory responses.
Animals ; Male ; Dementia, Vascular/physiopathology* ; Rats ; Signal Transduction ; Moxibustion ; Rats, Wistar ; CA1 Region, Hippocampal/injuries* ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; Caspase 1/genetics* ; Memory ; Humans ; Neurons/metabolism* ; Learning

OBJECTIVE: To investigate the role of α7-nicotinic acetylcholine receptor (α7-nAChR) in the regulation of neuronal activity and expression of synapse-related proteins in the thalamic reticular nucleus (TRN) of insomnia rats treated by acupuncture. METHODS: A total of 36 male Sprague-Dawley (SD) rats of clean grade were randomly divided into a control group, a model group, an acupuncture group, and an acupuncture+antagonist group, with 9 rats in each group. The model group, the acupuncture group, and the acupuncture+antagonist group were treated with intraperitoneal injection of p-chlorophenylalanine (PCPA) to establish insomnia model. After successful modeling, the acupuncture group and the acupuncture+antagonist group received acupuncture at bilateral Neiguan (PC6) and Zusanli (ST36) once daily for 5 consecutive days. Thirty min before each acupuncture session, the acupuncture+antagonist group was intraperitoneally injected with methyllycaconitine citrate (MLA), an α7-nAChR antagonist, at a dosage of 5 mg/kg while the acupuncture group received the same volume of 0.9% sodium chloride solution. The rats' daytime spontaneous activity was observed. Neuronal discharge in the TRN was detected using neuroelectrophysiological methods. Immunofluorescence staining was used to detect parvalbumin-positive (PV⁺) neurons and co-expression of PV⁺ and postsynaptic density protein-95 (PSD-95) in the TRN. RESULTS: Compared with the control group, the model group showed increased daytime spontaneous activity (P<0.01); decreased average fluorescence intensity and positive number of PV⁺ neurons in the TRN (P<0.01); decreased neuronal discharge frequency (P<0.01), prolonged inter-discharge intervals (P<0.01) in the TRN; reduced number of PV⁺/PSD-95 double-positive cells in the TRN (P<0.01). Compared with the model group, the acupuncture group showed decreased daytime spontaneous activity (P<0.01); increased average fluorescence intensity and positive number of PV⁺ neurons in the TRN (P<0.01); increased neuronal discharge frequency (P<0.01), shortened inter-discharge intervals (P<0.01) in the TRN; increased number of PV⁺/PSD-95 double-positive cells in the TRN (P<0.05). Compared with the acupuncture group, the acupuncture+antagonist group exhibited increased daytime spontaneous activity (P<0.01); reduced average fluorescence intensity and positive number of PV⁺ neurons in the TRN (P<0.01); decreased neuronal discharge frequency (P<0.05), prolonged inter-discharge intervals (P<0.05) in the TRN; reduced number of PV⁺/PSD-95 double-positive cells in the TRN (P<0.01). CONCLUSION α7-nAChR are involved in mediating the regulatory effect of acupuncture on circadian rhythm disturbances in PCPA-induced insomnia rats. Blocking α7-nAChR attenuates the activating effect of acupuncture on TRN neurons, and reduces the expression of PSD-95 protein on GABAergic neurons.
Animals ; Male ; Acupuncture Therapy ; alpha7 Nicotinic Acetylcholine Receptor/genetics* ; Rats, Sprague-Dawley ; Rats ; Sleep Initiation and Maintenance Disorders/physiopathology* ; Neurons/metabolism* ; Humans ; Thalamic Nuclei/physiopathology* ; Acupuncture Points ; Disks Large Homolog 4 Protein

The study aimed to investigate the effect of the CD200R1 gene deletion on microglia activation and nigrostriatal dopamine neuron loss in the Parkinson's disease (PD) process. The CRISPR-Cas9 technology was applied to construct the CD200R1^-/- mice. The primary microglia cells of wild-type and CD200R1^-/- mice were cultured and treated with bacterial lipopolysaccharide (LPS). Microglia phagocytosis level was assessed by a fluorescent microsphere phagocytosis assay. PD mouse model was prepared by nigral stereotaxic injection of recombinant adeno-associated virus vector carrying human α-synuclein (α-syn). The changes in the motor behavior of the mice with both genotypes were evaluated by cylinder test, open field test, and rotarod test. Immunohistochemical staining was used to assess the loss of dopamine neurons in substantia nigra. Immunofluorescence staining was used to detect the expression level of CD68 (a key molecule involved in phagocytosis) in microglia. The results showed that CD200R1 deletion markedly enhanced LPS-induced phagocytosis in vitro by the microglial cells. In the mouse model of PD, CD200R1 deletion exacerbated motor behavior impairment and dopamine neuron loss in substantia nigra. Fluorescence intensity analysis results revealed a significant increase in CD68 expression in microglia located in the substantia nigra of CD200R1^-/- mice. The above results suggest that CD200R1 deletion may further activates microglia by promoting microglial phagocytosis, leading to increased loss of the nigrostriatal dopamine neurons in the PD model mice. Therefore, targeting CD200R1 could potentially serve as a novel therapeutic target for the treatment of early-stage PD.
Animals ; Microglia/physiology* ; Mice ; Phagocytosis ; Parkinson Disease/genetics* ; Disease Models, Animal ; Receptors, Cell Surface/physiology* ; Dopaminergic Neurons/pathology* ; Antigens, CD/metabolism* ; Gene Deletion ; Substantia Nigra ; Mice, Inbred C57BL ; Mice, Knockout ; Cells, Cultured ; Male ; alpha-Synuclein ; CD68 Molecule ; Orexin Receptors

Currently, the incidence of Parkinson's disease (PD) is on the rise. More and more evidences suggest that mitochondrial dysfunction plays a crucial role in the etiology of PD, and dysfunction of mitochondrial complex I (MCI) is one of the most critical factors leading to mitochondrial dysfunction. On one hand, MCI dysfunction stimulates dopaminergic neurons to produce reactive oxygen species (ROS). On the other hand, MCI dysfunction decreases dopaminergic neuron viability and reduces ATP production. All these outcomes promote the pathological progression of PD. This review summarizes research progress on the role of MCI in the pathogenesis of PD, as well as PD treatment strategies based on MCI.
Parkinson Disease/metabolism* ; Humans ; Electron Transport Complex I/metabolism* ; Mitochondria/physiology* ; Reactive Oxygen Species/metabolism* ; Dopaminergic Neurons/metabolism* ; Animals ; Adenosine Triphosphate/metabolism*

The etiology of nervous system diseases is complicated, posing significant harm to patients and often resulting in poor prognoses. In recent years, the role of dopaminergic system in nervous system diseases has attracted much attention, and its complex regulatory mechanism and therapeutic potential have been gradually revealed. This paper reviews the role of dopaminergic neurons, the neurotransmitter dopamine, dopamine receptors and dopamine transporters in neurological diseases (including Alzheimer's disease, Parkinson's disease and schizophrenia), with a view to further elucidating the disease mechanism and providing new insights and strategies for the treatment of neurological diseases.
Humans ; Dopamine/metabolism* ; Nervous System Diseases/physiopathology* ; Parkinson Disease/physiopathology* ; Receptors, Dopamine/metabolism* ; Dopaminergic Neurons/physiology* ; Dopamine Plasma Membrane Transport Proteins/metabolism* ; Alzheimer Disease/physiopathology* ; Schizophrenia/physiopathology* ; Animals

The purpose of this study was to investigate the anxiety-like behaviors, circadian rhythms and sleep, and to elucidate the possible underlying mechanisms of the abnormal sleep behavior in Shank3 gene knockout (Shank3-KO) mice. The anxiety-like behaviors were detected by elevated plus-maze (EPM) test, open field test (OFT) and tail suspension test (TST). The circadian rhythms were detected by running wheel test. The electroencephalogram (EEG)/electromyogram (EMG) recordings were performed synchronically by polysomnograph. The distribution of SHANK3 in anterior cingulate cortex (ACC), paraventricular thalamus (PVT), nucleus accumbens (NAc), basolateral amygdala (BLA) and hippocampal CA2 region in wild type (WT) mice was detected by immunofluorescence assay. The protein expression of c-Fos in PVT, ACC and NAc was also detected by immunofluorescence assay during light cycle. The colocalization of c-Fos and vesicular glutamate transporter 2 (Vglut2, a marker for glutamatergic neurons) in the PVT was detected by immunofluorescence double labeling experiment. The results of EPM test showed that, compared with the WT mice, the Shank3-KO mice showed less time in open arms and less number of open arm entries. The results of OFT showed that the Shank3-KO mice showed less time in central area and less number of central area entries. The immobility time of Shank3-KO mice was increased in the TST. The results of running wheel rhythm test showed that the phase shift time of Shank3-KO mice in the continuous dark period was increased. The results of EEG/EMG recording showed that, compared with the WT mice, the duration of wakefulness in Shank3-KO mice was increased and the duration of non-rapid eye movement (NREM) sleep was decreased during light phase; The bout number of wakefulness was increased, the bout number of NREM sleep was decreased, NREM-wake transitions were increased, and wake-NREM transitions were decreased during light phase. SHANK3 was expressed in ACC, PVT, NAc and BLA in the WT mice. The expression of c-Fos in the PVT of Shank3-KO mice was up-regulated 2 h after entering the light phase, and majority of c-Fos was co-localized with Vglut2. These results suggest that the anxiety level of Shank3-KO mice is increased, the regulation of the internal rhythms is decreased, and the bout number of wakefulness is increased during light phase. The glutamatergic neurons in PVT may be involved in the regulation of abnormal sleep behavior in Shank3-KO mice during the light phase.
Animals ; Mice, Knockout ; Mice ; Neurons/metabolism* ; Nerve Tissue Proteins/physiology* ; Male ; Midline Thalamic Nuclei/cytology* ; Circadian Rhythm/physiology* ; Sleep/physiology* ; Anxiety/physiopathology* ; Proto-Oncogene Proteins c-fos/metabolism* ; Vesicular Glutamate Transport Protein 2/metabolism* ; Mice, Inbred C57BL ; Microfilament Proteins

Buyang Huanwu Decoction(BYHWD), as one of the classic formulas in traditional Chinese medicine(TCM) for the treatment of cerebral ischemic stroke(CIS), has demonstrated definite effects in clinical practice. However, the material basis and mechanism of treatment have not been systematically elucidated. This study employed network pharmacology and molecular docking to analyze the potential targets and mechanisms of blood-and brain-penetrating active components of BYHWD in reducing cell apoptosis in CIS. Cell experiments were then carried out to validate the prediction results. In the experiments, five active components including hydroxysafflor yellow A( HSYA), tetramethylpyrazine( TMP), astragaloside Ⅳ( AS-Ⅳ), amygdalin( AMY), and paeoniflorin(PF) were selected to explore the pharmacological effects of BYHWD. HT22 cells were treated with BYHWD, and the cell counting kit-8(CCK-8) method was employed to examine the toxic and side effects of BYHWD. A cell model of oxygen-glucose deprivation/reoxygenation( OGD/R) was constructed, with apoptosis and pyroptosis as the main screening indicators. The levels of lactate dehydrogenase(LDH) and glutathione(GSH) were measured to assess the cell membrane integrity. Flow cytometry was employed to detect apoptosis, and the activities of caspase-3 and caspase-1 were measured to clarify the status of apoptosis and pyroptosis. ELISA was employed to determine the levels of interleukin(IL)-1β and IL-18 to confirm pyroptosis. HSYA and AMY were identified in this study as the active components regulating apoptosis and pyroptosis. TUNEL was employed to detect the apoptosis rate, and Western blot was employed to determine the expression levels of apoptosis-related proteins B-cell lymphoma-2(Bcl-2), Bcl-2-associated X protein(Bax), and caspase-3, which confirmed that the anti-apoptotic effect of the combined component group was superior to that of the single component groups. The molecular docking results revealed strong binding affinity of HSYA and AMY with SDF-1α and CXCR4.AMD3100, a selective antagonist of CXCR4, was then used for intervention. The results of Western blot showed alterations in the expression levels of apoptosis-associated proteins, SDF-1α, and CXCR4. In conclusion, HSYA and AMY influence cellular apoptosis by modulating the SDF-1α/CXCR4 signaling cascade.
Drugs, Chinese Herbal/chemistry* ; Apoptosis/drug effects* ; Animals ; Neurons/cytology* ; Mice ; Molecular Docking Simulation ; Cell Line ; Glucose/metabolism* ; Humans ; Neuroprotective Agents/pharmacology*

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)

OBJECTIVE: To explore the effects and mechanisms of the C-X-C motif chemokine ligand 12/C-X-C motif chemokine receptor 4 (CXCL12/CXCR4) signaling axis on apoptosis and autophagy in SH-SY5Y neuronal cells subjected to oxygen-glucose deprivation/reperfusion (OGD/R) model in vitro. METHODS: SH-SY5Y cells were divided into the following groups: OGD/R group and non-OGD/R group, with the OGD/R group subjected to OGD/R modeling and the non-OGD/R group receiving no treatment. Cells were also divided into CXCL12⁺ and CXCL12^- groups; the CXCL12⁺ group received 0.1 mg/L exogenous recombinant CXCL12 (rhCXCL12) at reoxygenation, while the CXCL12^- group did not. Another set of cells was divided into CXCL12+AMD3100 and CXCL12 groups; the CXCL12+AMD3100 group was pretreated with 2.5 mg/L AMD3100, a CXCR4 inhibitor, for 2 hours before OGD/R and received both 2.5 mg/L AMD3100 and 0.1 mg/L rhCXCL12 at reoxygenation, whereas the CXCL12 group received rhCXCL12 only. Additionally, cells were divided into small interfering RNA CXCR4 (siCXCR4) and small interfering RNA negative control (siNC) groups; the siCXCR4 group underwent CXCR4 knockdown before OGD/R modeling and received 0.1 mg/L rhCXCL12 at reoxygenation, while the siNC group, transfected with a negative control, received the same treatment. Protein expression of autophagy-related 16 (ATG16), microtubule-associated protein 1 light chain 3 (LC3), aquaporin-3 (AQP3), and CXCR4 was detected by Western blotting. Apoptosis rate and CXCR4 expression were measured by flow cytometry. RESULTS: Compared with the non-OGD/R group, the OGD/R group showed a significantly increased apoptosis rate and markedly decreased protein expression levels of ATG16, LC3, AQP3, and CXCR4 (all P < 0.05). CXCR4 fluorescent expression was also significantly reduced, suggesting that OGD/R simultaneously affects neuronal apoptosis and autophagy while inhibiting CXCR4 and AQP3 expression in SH-SY5Y cells. Compared with the CXCL12^- group, the CXCL12⁺ group exhibited no significant change in apoptosis rate but demonstrated significantly increased protein expression of ATG16, LC3, and AQP3 (ATG16/GAPDH: 1.21±0.10 vs. 1.00±0.00; LC3/β-actin: 1.22±0.10 vs. 1.00±0.00; AQP3/β-actin: 1.26±0.04 vs. 1.00±0.00; all P < 0.05). CXCR4 expression was also significantly enhanced (fluorescence intensity: 1.19±0.05 vs. 1.00±0.00, P < 0.05), indicating that CXCL12 may promote autophagy in OGD/R-injured SH-SY5Y cells via the CXCR4/AQP3 pathway. Compared with the CXCL12 group, the CXCL12+AMD3100 group showed no significant difference in apoptosis rate but significantly lower protein levels of ATG16 and LC3 (ATG16/GAPDH: 0.75±0.08 vs. 1.00±0.00; LC3/GAPDH: 0.86±0.07 vs. 1.00±0.00; both P < 0.05), suggesting that CXCL12 induces autophagy in OGD/R SH-SY5Y cells through CXCR4. Compared with the siNC group, the siCXCR4 group showed no significant change in apoptosis rate but significantly reduced protein expression of ATG16, LC3, AQP3, and CXCR4 (ATG16/GAPDH: 0.76±0.06 vs. 1.00±0.00; LC3/GAPDH: 0.79±0.11 vs. 1.00±0.00; AQP3/GAPDH: 0.81±0.05 vs. 1.00±0.00; CXCR4/GAPDH: 0.86±0.04 vs. 1.00±0.00; all P < 0.05), indicating that CXCR4 knockdown suppresses OGD/R-induced autophagy in SH-SY5Y cells likely via AQP3. CONCLUSIONS The CXCL12/CXCR4 signaling axis can regulate OGD/R-induced autophagy in SH-SY5Y cells through AQP3 without affecting apoptosis, indicating a role for this pathway in neuronal autophagy during cerebral ischemia/reperfusion injury.
Humans ; Receptors, CXCR4/metabolism* ; Chemokine CXCL12/metabolism* ; Autophagy ; Glucose/metabolism* ; Apoptosis ; Neurons/cytology* ; Oxygen/metabolism* ; Signal Transduction ; Cell Line, Tumor ; Cell Hypoxia ; Benzylamines ; Cyclams