Microglial functions are linked to Ca²⁺ signaling, with endoplasmic reticulum (ER) calcium stores playing a crucial role. Microglial abnormality is a hallmark of Alzheimer's disease (AD), but how ER Ca²⁺ receptors regulate microglial functions under physiological and AD conditions remains unclear. We found reduced ryanodine receptor 2 (Ryr2) expression in microglia from an AD mouse model. Modulation of RyR2 using S107, a RyR-Calstabin stabilizer, blunted spontaneous Ca²⁺ transients in controls and normalized Ca²⁺ transients in AD mice. S107 enhanced ATP-induced migration and phagocytosis while reducing ramification in control microglia; however, these effects were absent in AD microglia. Our findings indicate that RyR2 stabilization promotes an activation state shift in control microglia, a mechanism impaired in AD. These results highlight the role of ER Ca²⁺ receptors in both homeostatic and AD microglia, providing insights into microglial Ca²⁺ malfunctions in AD.
Animals ; Microglia/pathology* ; Alzheimer Disease/pathology* ; Phagocytosis/drug effects* ; Ryanodine Receptor Calcium Release Channel/metabolism* ; Disease Models, Animal ; Mice ; Cell Movement/drug effects* ; Mice, Transgenic ; Calcium Signaling/physiology* ; Calcium/metabolism* ; Mice, Inbred C57BL ; Male ; Endoplasmic Reticulum/metabolism*

Astrocytes in the spinal dorsal horn (SDH) exhibit diverse reactive phenotypes under neuropathic conditions, yet the mechanisms driving this diversity and its implications in chronic pain remain unclear. Here, we report that spared nerve injury (SNI) induces marked upregulation of both complement component 3 (C3⁺, A1-like) and S100 calcium-binding protein A10 (S100A10⁺, A2-like) astrocyte subpopulations in the SDH, with elevated microglial cytokines including interleukin-1α, tumor necrosis factor-α, and complement component 1q. Transcriptomic, immunohistochemical, and Western blot analyses reveal co-activation of multiple reactive astrocyte states over a unidirectional shift toward an A1-like phenotype. Fibroblast growth factor 8 (FGF8), a neuroprotective factor via FGFR3, mitigated microglia-induced C3⁺ astrocyte reactivity in vitro and suppressed spinal C3 expression and mechanical allodynia following intrathecal administration in SNI mice. These findings reveal a microglia-astrocyte signaling axis that promotes A1 reactivity and position FGF8 as a promising therapeutic candidate for neuropathic pain by modulating astrocyte heterogeneity.
Animals ; Astrocytes/drug effects* ; Neuralgia/pathology* ; Receptor, Fibroblast Growth Factor, Type 3/metabolism* ; Signal Transduction/physiology* ; Male ; Mice ; Microglia/drug effects* ; Fibroblast Growth Factor 8/pharmacology* ; Mice, Inbred C57BL ; Hyperalgesia/drug therapy* ; Spinal Cord/drug effects* ; Complement C3/metabolism* ; Spinal Cord Dorsal Horn/metabolism*

Study on the mechanism of Fangxia Dihuang Formula(FXDH) in treating breast cancer complicated with depression through the regulation of M1/M2 microglial polarization via the PERK/eIF2α axis. In addition to control group and 4T1 group, a mouse model of breast cancer complicated with depression was established using 4T1 cells combined with corticosterone. The mice were divided into model group, PERK/eIF2α signaling axis agonist(CCT020312, 2 mg·kg~(-1)·d~(-1)) group, CCT020312(2 mg·kg~(-1)·d~(-1)) + FXDH(13.65 g·kg~(-1)·d~(-1)) group, FXDH(13.65 g·kg~(-1)·d~(-1)) group, FXDH(13.65 g·kg~(-1)·d~(-1)) + Capecitabine Tablets(CAP, 390 mg·kg~(-1)·d~(-1)) group, and Fluoxetine Hydrochloride Capsules(FXT, 2.6 mg·kg~(-1)·d~(-1)) + CAP(390 mg·kg~(-1)·d~(-1)) group, with continuous intervention for 21 d. Depression-like behaviors in mice were assessed through sugar preference test and open field test. Hematoxylin-eosin(HE) staining was used to evaluate the morphology of tumor and hippocampal DG region neurons. Nissl staining was employed to detect changes in Nissl bodies in the hippocampal CA3 region. Immunofluorescence was used to observe cluster of differentiation 86(CD86)/ionized calcium-binding adapter molecule 1(Iba-1) and cluster of differentiation 206(CD206)/Iba-1 in hippocampal tissue. Real-time fluorescence quantitative polymerase chain reaction(RT-qPCR) was used to detect the mRNA expression of M1-type microglia [interleukin-6(IL-6), tumor necrosis factor-α(TNF-α)] and M2-type [arginase-1(Arg-1), IL-10] in hippocampal tissue. Western blot was used to detect the protein expression of key factors in the PERK/eIF2α axis, including PERK, eIF2α, activating transcription factor 4(ATF4), and C/EBP homologous protein(CHOP) in hippocampal tissue. The results showed that compared to model group/CCT020312 + FXDH group, FXDH group increased sugar preference index, total movement distance, central zone distance, and central zone entries; reduced tumor mass and volume; tumor cells were sparsely arranged, with a smaller nuclear-to-cytoplasmic ratio and reduced nuclear division figures, increased Nissl body count, and alleviated neuronal nuclear pyknosis; increased CD206-positive M2-type microglia expression, decreased CD86/Iba-1-positive M1-type microglia expression; reduced IL-6 and TNF-α mRNA expression, and increased Arg-1 and IL-10 mRNA expression; downregulated PERK, eIF2α, ATF4, and CHOP protein expression levels. The results indicate that the mechanism of FXDH in treating breast cancer complicated with depression may be related to inhibiting the activity of the PERK/eIF2α axis, reducing the proportion of M1-type microglia, increasing the proportion of M2-type microglia, thereby suppressing neuronal immune inflammation, improving depressive symptoms, and subsequently delaying the progression of breast cancer.
Animals ; Drugs, Chinese Herbal/administration & dosage* ; Female ; Microglia/cytology* ; Mice ; Depression/complications* ; eIF-2 Kinase/genetics* ; Humans ; Breast Neoplasms/psychology* ; Eukaryotic Initiation Factor-2/genetics* ; Mice, Inbred BALB C ; Signal Transduction/drug effects* ; Cell Line, Tumor

This study aims to explore the effects and action mechanisms of the active ingredients in Buyang Huanwu Decoction(BYHWD), namely tetramethylpyrazine(TMP) and hydroxy-safflor yellow A(HSYA), on oxygen-glucose deprivation/reglucose-reoxygenation(OGD/R)-induced inflammation and oxidative stress of microglia(MG). Network pharmacology was used to screen the effective monomer ingredients of BYHWD and determine the safe concentration range for each component. Inflammation and oxidative stress models were established to further screen the best ingredient combination and optimal concentration ratio with the most effective anti-inflammatory and antioxidant effects. OGD/R BV2 cell models were constructed, and BV2 cells in the logarithmic growth phase were divided into a normal group, a model group, an HSYA group, a TMP group, and an HSYA + TMP group. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of inflammatory cytokines such as interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and interleukin-6(IL-6). Oxidative stress markers, including superoxide dismutase(SOD), nitric oxide(NO), and malondialdehyde(MDA), were also measured. Western blot was used to analyze the protein expression of both inflammation-related pathway [Toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB)] and oxidative stress-related pathway [nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)]. Immunofluorescence was used to assess the expression of proteins such as inducible nitric oxide synthase(iNOS) and arginase-1(Arg-1). The most effective ingredients for anti-inflammatory and antioxidant effects in BYHWD were TMP and HSYA. Compared to the normal group, the model group showed significantly increased levels of IL-1β, TNF-α, IL-6, NO, and MDA, along with significantly higher protein expression of NF-κB, TLR4, Nrf2, and HO-1 and significantly lower SOD levels. The differences between the two groups were statistically significant. Compared to the model group, both the HSYA group and the TMP group showed significantly reduced levels of IL-1β, TNF-α, IL-6, NO, and MDA, lower expression of NF-κB and TLR4 proteins, higher levels of SOD, and significantly increased protein expression of Nrf2 and HO-1. Additionally, the expression of the M1-type MG marker iNOS was significantly reduced, while the expression of the M2-type MG marker Arg-1 was significantly increased. The results of the HSYA group and the TMP group had statistically significant differences from those of the model group. Compared to the HSYA group and the TMP group, the HSYA + TMP group showed further significant reductions in IL-1β, TNF-α, IL-6, NO, and MDA levels, along with significant reductions in NF-κB and TLR4 protein expression, an increase in SOD levels, and elevated Nrf2 and HO-1 protein expression. Additionally, the expression of the M1-type MG marker iNOS was reduced, while the M2-type MG marker Arg-1 expression increased significantly in the HSYA + TMP group compared to the TMP or HSYA group. The differences in the results were statistically significant between the HSYA + TMP group and the TMP or HSYA group. The findings indicated that the combined use of HSYA and TMP, the active ingredients of BYHWD, can effectively inhibit OGD/R-induced inflammation and oxidative stress of MG, showing superior effects compared to the individual use of either component.
Oxidative Stress/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Animals ; Mice ; Glucose/metabolism* ; Cell Line ; Inflammation/genetics* ; Oxygen/metabolism* ; Pyrazines/pharmacology* ; Microglia/metabolism* ; NF-E2-Related Factor 2/immunology* ; NF-kappa B/immunology* ; Toll-Like Receptor 4/immunology* ; Anti-Inflammatory Agents/pharmacology* ; Humans

OBJECTIVE: To investigate the effects of removing microglia from spinal cord on nerve repair and functional recovery after spinal cord injury (SCI) in mice. METHODS: Thirty-nine 6-week-old female C57BL/6 mice were randomly divided into control group ( n=12), SCI group ( n=12), and PLX3397+SCI group ( n=15). The PLX3397+SCI group received continuous feeding of PLX3397, a colony-stimulating factor 1 receptor inhibitor, while the other two groups were fed a standard diet. After 14 days, both the SCI group and the PLX3397+SCI group were tested for ionized calcium binding adapter molecule 1 (Iba1) to confirm that the PLX3397+SCI group had completely depleted the spinal cord microglia. The SCI model was then prepared by clamping the spinal cord in both the SCI group and the PLX3397+SCI group, while the control group underwent laminectomy. Preoperatively and at 1, 3, 7, 14, 21, and 28 days postoperatively, the Basso Mouse Scale (BMS) was used to assess the hind limb function of mice in each group. At 28 days, a footprint test was conducted to observe the gait of the mice. After SCI, spinal cord tissue from the injury site was taken, and Iba1 immunofluorescence staining was performed at 7 days to observe the aggregation and proliferation of microglia in the spinal cord. HE staining was used to observe the formation of glial scars at the injury site at 28 days; glial fibrillary acidic protein (GFAP) immunofluorescence staining was applied to astrocytes to assess the extent of the injured area; neuronal nuclei antigen (NeuN) immunofluorescence staining was used to evaluate neuronal survival. And 5-hydroxytryptamine (5-HT) immunofluorescence staining was performed to assess axonal survival at 60 days. RESULTS: All mice survived until the end of the experiment. Immunofluorescence staining revealed that the microglia in the spinal cord of the PLX3397+SCI group decreased by more than 95% compared to the control group after 14 days of continuous feeding with PLX3397 ( P<0.05). Compared to the control group, the BMS scores in the PLX3397+SCI group and the SCI group significantly decreased at different time points after SCI ( P<0.05). Moreover, the PLX3397+SCI group showed a further decrease in BMS scores compared to the SCI group, and exhibited a dragging gait. The differences between the two groups were significant at 14, 21, and 28 days ( P<0.05). HE staining at 28 days revealed that the SCI group had formed a well-defined and dense gliotic scar, while the PLX3397+SCI group also developed a gliotic scar, but with a more blurred and loose boundary. Immunofluorescence staining revealed that the number of microglia near the injury center at 7 days increased in the SCI group than in the control group, but the difference between groups was not significant ( P>0.05). In contrast, the PLX3397+SCI group showed a significant reduction in microglia compared to both the control and SCI groups ( P<0.05). At 28 days after SCI, the area of spinal cord injury in the PLX3397+SCI group was significantly larger than that in SCI group ( P<0.05); the surviving neurons significantly reduced compared with the control group and SCI group ( P<0.05). The axonal necrosis and retraction at 60 days after SCI were more obvious. CONCLUSION The removal of microglia in the spinal cord aggravate the tissue damage after SCI and affecte the recovery of motor function in mice, suggesting that microglia played a neuroprotective role in SCI.
Animals ; Spinal Cord Injuries/surgery* ; Microglia/pathology* ; Female ; Mice ; Mice, Inbred C57BL ; Nerve Regeneration/drug effects* ; Spinal Cord/pathology* ; Pyrroles/administration & dosage* ; Aminopyridines/administration & dosage* ; Recovery of Function ; Disease Models, Animal ; Calcium-Binding Proteins/metabolism* ; Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors* ; Microfilament Proteins/metabolism* ; Glial Fibrillary Acidic Protein/metabolism*

Stem-leaf saponins from Panax notoginseng (SLSP) comprise numerous PPD-type saponins with diverse pharmacological properties; however, their role in Parkinson's disease (PD), characterized by microglia-mediated neuroinflammation, remains unclear. This study evaluated the effects of SLSP on suppressing microglia-driven neuroinflammation in experimental PD models, including the 1-methyl-4-phenylpyridinium (MPTP)-induced mouse model and lipopolysaccharide (LPS)-stimulated BV-2 microglia. Our findings revealed that SLSP mitigated behavioral impairments and excessive microglial activation in models of PD, including MPTP-treated mice. Additionally, SLSP inhibited the upregulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) and attenuated the phosphorylation of PI3K, protein kinase B (AKT), nuclear factor-κB (NFκB), and inhibitor of NFκB protein α (IκBα) both in vivo and in vitro. Moreover, SLSP suppressed the production of inflammatory markers such as interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha (TNF-α) in LPS-stimulated BV-2 cells. Notably, the P2Y2R agonist partially reversed the inhibitory effects of SLSP in LPS-treated BV-2 cells. These results suggest that SLSP inhibit microglia-mediated neuroinflammation in experimental PD models, likely through the P2Y2R/PI3K/AKT/NFκB signaling pathway. These novel findings indicate that SLSP may offer therapeutic potential for PD by attenuating microglia-mediated neuroinflammation.
Animals ; Panax notoginseng/chemistry* ; Saponins/pharmacology* ; Microglia/immunology* ; Mice ; NF-kappa B/immunology* ; Signal Transduction/drug effects* ; Proto-Oncogene Proteins c-akt/immunology* ; Phosphatidylinositol 3-Kinases/genetics* ; Male ; Parkinson Disease/immunology* ; Mice, Inbred C57BL ; Disease Models, Animal ; Plant Leaves/chemistry* ; Neuroinflammatory Diseases/drug therapy* ; Humans

Triggering receptor expressed on myeloid cells 2 (TREM2)-mediated microglial phagocytosis is an energy-intensive process that plays a crucial role in amyloid beta (Aβ) clearance in Alzheimer's disease (AD). Energy metabolic reprogramming (EMR) in microglia induced by TREM2 presents therapeutic targets for cognitive impairment in AD. Jiawei Xionggui Decoction (JWXG) has demonstrated effectiveness in enhancing energy supply, protecting microglia, and mitigating cognitive impairment in APP/PS1 mice. However, the mechanism by which JWXG enhances Aβ phagocytosis through TREM2-mediated EMR in microglia remains unclear. This study investigates how JWXG facilitates microglial phagocytosis and alleviates cognitive deficits in AD through TREM2-mediated EMR. Microglial phagocytosis was evaluated through immunofluorescence staining in vitro and in vivo. The EMR level of microglia was assessed using high-performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay (ELISA) kits. The TREM2/protein kinase B (Akt)/mammalian target of rapamycin (mTOR)/hypoxia-inducible factor-1α (HIF-1α) signaling pathway was analyzed using Western blotting in BV₂ cells. TREM2^-/- BV₂ cells were utilized for reverse validation experiments. The Aβ burden, neuropathological features, and cognitive ability in APP/PS1 mice were evaluated using ELISA kits, immunohistochemistry (IHC), and the Morris water maze (MWM) test. JWXG enhanced both the phagocytosis of EMR disorder-BV₂ cells (EMRD-BV₂) and increased EMR levels. Notably, these effects were significantly reversed in TREM2^-/- BV₂ cells. JWXG elevated TREM2 expression, adenosine triphosphate (ATP) levels, and microglial phagocytosis in APP/PS1 mice. Additionally, JWXG reduced Aβ-burden, neuropathological lesions, and cognitive deficits in APP/PS1 mice. In conclusion, JWXG promoted TREM2-induced EMR and enhanced microglial phagocytosis, thereby reducing Aβ deposition, improving neuropathological lesions, and alleviating cognitive deficits.
Drugs, Chinese Herbal/pharmacology* ; Microglia/drug effects* ; Phagocytosis ; Cognitive Dysfunction/drug therapy* ; Metabolic Reprogramming ; Animals ; Mice ; Cell Line ; Receptors, Immunologic/metabolism* ; Membrane Glycoproteins/metabolism* ; Signal Transduction ; Amyloid beta-Peptides/metabolism* ; Energy Metabolism

Thirteen novel diterpenoids, comprising seven tiglianes (walliglianes G-M, 1-7), four rhamnofolanes (wallinofolanes A-D, 8-11), and two daphnanes (wallaphnanes A and B, 12 and 13), together with two known rhamnofolane diterpenoids (euphorwallside H and euphorwallside I, 14 and 15), were isolated and characterized from Euphorbia wallichii(E. wallichii). The chemical structures of these compounds were elucidated through nuclear magnetic resonance (NMR), mass spectrometry (MS), and quantum chemical calculations. Compounds 9 and 11 demonstrated protective effects against H₂O₂-induced BV-2 microglial cell damage. Molecular docking analyses indicated that compound 9 exhibited binding affinity to the anti-oxidant-related targets HMGCR, GSTP1, and SHBG.
Euphorbia/chemistry* ; Antioxidants/isolation & purification* ; Diterpenes/isolation & purification* ; Molecular Structure ; Mice ; Molecular Docking Simulation ; Animals ; Hydrogen Peroxide/toxicity* ; Cell Line ; Microglia/drug effects*

Objective To explore the effects of Shuanglu Tongnao Formula on neuroinflammation in ischemic stroke (IS) rats via the P2X purinoceptor 7 receptor (P2X7R)/NLR family pyrin domain-containing 3 (NLRP3) pathway. Methods The rats were divided into five groups: the IS group, control group, Shuanglu Tongnao Formula group, P2X7R inhibitor brilliant blue G (BBG) group, and Shuanglu Tongnao Formula combined with P2X7R activator adenosine triphosphate (ATP) group, with 18 rats in each group. Except for the control group, rats in all other groups were used to construct an IS model using the suture method. After successful modeling, the drug was given once a day for 2 weeks. Neurological function scores and cerebral infarction volume ratios were measured in rats. Pathological examination of the ischemic penumbra brain tissue was performed. Immunofluorescence staining was used to quantify the proportions of microglia co-expressing both inducible nitric oxide synthase (iNOS) and ionized calcium-binding adapter molecule 1 (Iba1), as well as arginase 1 (Arg1) and Iba1, in the ischemic penumbra brain tissue. ELISA was used to detect tumor necrosis factor-alpha (TNF-α), transforming growth factor-beta (TGF-β), interleukin 6 (IL-6) and IL-10 in the ischemic penumbra brain tissue. Western blotting was used to measure P2X7R, NLRP3, and IL-1β proteins in the ischemic penumbra brain tissue. Results Compared with the control group, the IS group showed disordered neuronal arrangement, nuclear condensation, and obvious infiltration of inflammatory cells in the ischemic penumbra; significantly elevated neurological function scores, cerebral infarction volume ratios, proportions of microglia co-expressing iNOS and Iba1, and levels of TNF-α, IL-6, and P2X7R, NLRP3, IL-1β proteins; along with reduced proportions of microglia co-expressing Arg1 and Iba1 and levels of TGF-β and IL-10. Compared with the IS group, the Zhuang medicine Shuanglu Tongnao Formula and BBG groups demonstrated alleviated brain tissue damage; reduced neurological function scores, cerebral infarction volume ratios, proportions of microglia co-expressing iNOS and Iba1, and levels of TNF-α, IL-6, and P2X7R, NLRP3, IL-1β proteins; along with increased proportions of microglia co-expressing Arg1 and Iba1 and levels of TGF-β and IL-10. ATP reversed the effects of Zhuang medicine Shuanglu Tongnao Formula on microglial polarization and neuroinflammation in IS rats. Conclusion Zhuang medicine Shuanglu Tongnao Formula may promote the transformation of microglia from M1 type to M2 type by inhibiting the P2X7R/NLRP3 pathway, thereby improving neuroinflammation in IS rats.
Animals ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Receptors, Purinergic P2X7/metabolism* ; Male ; Drugs, Chinese Herbal/pharmacology* ; Rats ; Ischemic Stroke/pathology* ; Rats, Sprague-Dawley ; Disease Models, Animal ; Signal Transduction/drug effects* ; Neuroinflammatory Diseases/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Nitric Oxide Synthase Type II/metabolism* ; Interleukin-10/metabolism* ; Brain Ischemia/drug therapy* ; Microglia/metabolism*

OBJECTIVE: To investigate the therapeutic effect of Xiangshao Granules (XSG) on post-stroke depression (PSD) and explore the underlying mechanisms. METHODS: Forty-three C57BL/6J mice were divided into 3 groups: sham (n=15), PSD+vehicle (n=14), and PSD+XSG (n=14) groups according to a random number table. The PSD models were constructed using chronic unpredictable mild stress (CUMS) after middle cerebral artery occlusion (MCAO). The sham group only experienced the same surgical operation, but without MACO and CUMS stimulation. The XSG group received XSG (60 mg/kg per day) by gavage for 4 weeks. The mice in the sham and vehicle groups were given the same volume of 0.9% saline at the same time. The body weight and behavior tests including open field test, sucrose preference test, tail suspension test, and elevated plus-maze test, were used to validate the PSD mouse model. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), and immunofluorescence staining were used to evaluate the anti-inflammatory effects of XSG. The potential molecular mechanisms were explored and verified through network pharmacology analysis, Nissl staining, Western blot, ELISA, and RT-qPCR, respectively. RESULTS: The body weight and behavior tests showed that MCAO combined with CUMS successfully established the PSD models. XSG alleviated neuronal damage, reduced the expressions of pro-apoptotic proteins Caspase-3 and B-cell lymphoma-2 (BCL-2)-associated X (BAX), and increased the expression of anti-apoptotic protein BCL-2 in PSD mice (P<0.05 or P<0.01). XSG inhibited microglial activation and the expressions of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin (IL)-1 β, and IL-6 via the toll-like receptor 4/nuclear factor kappa-B signaling pathway in PSD mice (P<0.05 or P<0.01). Furthermore, XSG decreased the expression of indoleamine 2,3-dioxygenase1 (IDO1) and increased the concentration of 5-hydroxytryptamine in PSD mice (P<0.05 or P<0.01). CONCLUSION XSG could reverse the anxiety/depressionlike behaviors and reduce the neuronal injury in the hippocampus and prefrontal cortex of PSD mice, which may be a potential therapeutic agent for PSD.
Animals ; Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism* ; Depression/etiology* ; Drugs, Chinese Herbal/therapeutic use* ; Hippocampus/metabolism* ; Male ; Mice, Inbred C57BL ; Prefrontal Cortex/pathology* ; Microglia/metabolism* ; Stroke/drug therapy* ; Disease Models, Animal ; Mice ; Behavior, Animal/drug effects*