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The repair mechanisms following sciatic nerve injury involve complex signaling interactions between neurons and microglia. Recent studies have demonstrated that neurons activate microglia by releasing chemokines, glutamate, and neurotrophic factors. In turn, microglia regulate neuronal survival and regeneration via phagocytosis, phenotypic switching, and secretion of growth factors. However, the spatiotemporal diversity of signaling pathways, metabolic regulation of the microenvironment, and barriers to clinical application remain inadequately addressed. This review provides a comprehensive analysis of morphological and functional changes in neuronal cell bodies and of the activation and regulatory mechanisms of microglia after sciatic nerve injury. It highlights the dynamic interaction network encompassing the ATP-P2X7 signaling pathway, the CX3CL1- CX3CR1 pathway, the CCL2-CCR2 chemokine axis, the BDNF-TrkB pathway, and inflammatory mediators, offering novel insights into precision therapeutic strategies targeting neuron-glial interactions. Show less

Attention deficit hyperactivity disorder(ADHD), a common neurodevelopmental disorder in children, is characterized by inattention, hyperactivity, and impulsivity. Epidemiological surveys show that the prevalence of ADHD in children is gradually increasing worldwide, and it is the most common childhood mental disorder in China. Because of the complex clinical symptoms, multiple co-morbidities, and unknown etiology, ADHD has far-reaching negative impacts on individuals, families, and the society. Behavioral interventions, as a pillar in the management of ADHD, play a targeted role in improving children's social functioning, with significant benefits supported by evidence. However, they are constrained by uneven resources, poor compliance, and insufficient continuity, Western medicine has multiple adverse effects and unclear long-term effects in the treatment of ADHD despite the definite efficacy. Accordingly, there is an urgent need to find safe and effective therapies suitable for children. With a holistic view and treatment based on syndrome differentiation, traditional Chinese medicine(TCM) has significant advantages in treating ADHD via multiple targets, which involves dopamine(DA), norepinephrine(NE), 5-hydroxytryptamine(5-HT), cyclic adenosine monophosphate(cAMP), brain-derived neurotrophic factor(BDNF) and other signaling pathways. Through these pathways, TCM can treat ADHD through the regulation of neurotransmitters, enhancement of prefrontal and striatal functions, enhancement of neuronal protection, attenuation of neuroinflammation, and reduction of neuronal apoptosis. However, a systematic study remains to be conducted. This paper summarizes the signaling pathways related to the treatment of ADHD by TCM in the past two decades, aiming to provide reference for delving into the mechanism and exploring effective TCM prescriptions for ADHD in children and to give full play to the advantages of the efficacy and characteristics of TCM. Show less

Neuroinflammation driven by dysfunctional microglial responses represents a critical early pathogenic process, particularly in the context of Alzheimer's disease (AD). The natural flavonoid fisetin possesses anti-inflammatory characteristics; however, the exact mechanisms via which it mitigates microglial dysfunction in AD are not fully elucidated. This work employed a combination of in vivo and in vitro approaches, utilizing male APP/PS1 mice and ADDL-stimulated primary microglia. Behavioral tests, immunohistochemistry, molecular profiling, and mitochondrial function assays were conducted. This research combines network pharmacology, molecular docking, and cellular thermal shift assays (CETSA) to offer predictive insights. Fisetin treatment improved cognitive performance in APP/PS1 mice, concurrently reducing amyloid pathology and plaque-associated microglial clustering. In primary microglia, fisetin potently inhibited ADDL-induced pro-inflammatory activation, mitochondrial ROS overproduction, and membrane depolarization. PI3K was identified as a signaling node potentially involved in fisetin-mediated regulation of microglial inflammatory responses. Accordingly, fisetin constrained microglial inflammatory signaling, at least in part through modulation of the PI3K-Akt-NF-κB axis, thereby limiting NF-κB nuclear translocation and pro-inflammatory cytokine release in both the mouse hippocampus and cultured primary microglia. Furthermore, conditioned medium from fisetin-treated microglia alleviated neuronal damage and restored the expression of BDNF and PSD95 in primary neurons. The collective findings, along with experimental studies utilizing the PI3K inhibitor (LY294002), indicate that PI3K may act as a molecular target of fisetin, underscoring its potential therapeutic significance in regulating early inflammatory processes in AD. Show less

Microplastic (MPs) pollution is widespread in the environment and poses growing risks to food safety and human health. In a 60-day oral exposure study, male Swiss mice received MPs (10 mg/kg b.wt), and the neuroprotective potential of taurine (Tau, 200 mg/kg b.wt) was evaluated. MPs exposure induced pronounced anxiety-like behavior, evidenced by increased peripheral zone activity in the open field test (+ 81.1%) and elevated anxiety index in the elevated plus maze (+ 75.9%), along with significant memory and spatial learning impairments in the Y-maze (increased trials + 31.6% and latency + 75.2%). Neurochemically, MPs increased acetylcholinesterase (AChE) activity (+ 89.4%) while reducing dopamine (-29.4%) and γ-aminobutyric acid (GABA) (-17.9%) levels. MPs also triggered marked oxidative stress, as shown by elevated reactive oxygen species (+ 107.6%) and malondialdehyde (+ 249.0%), accompanied by reduced total antioxidant capacity (-26.2%). At the molecular level, MPs downregulated CREB1 (-82.2%) and BDNF (-80.2%) while markedly upregulating AKT1 (~ fivefold) and pro-inflammatory cytokines (TNF-α, IL-6, CXCL-10, and IL-1β; 5.2-7.2-fold). Histopathological analysis revealed severe neurodegenerative alterations across the cerebrum, hippocampus, and cerebellum. Tau co-treatment significantly ameliorated MPs' induced neurotoxicity by reducing anxiety and memory deficits, lowering AChE activity (- 17.3%), restoring dopamine (+ 28.8%) and GABA (+ 14.2%) levels, attenuating oxidative stress (ROS -45.4% and MDA -44.7%), suppressing inflammatory gene expression (-51.0 to -68.1%), and partially normalizing CREB1 and BDNF expression (+239% and +240%, respectively). Collectively, these findings identify Tau as a promising natural neuroprotective agent against MPs' induced neurotoxicity. Show less

Depression is a major mental illness, and its underlying mechanisms remain unclear. Emerging evidence suggests that astrocytes, which play a crucial role in brain function, may be involved in the pathophysiology of depression. We previously showed that downregulation of astrocytic connexin43 (Cx43) enhances the antidepressant effect of amitriptyline. However, the precise molecular mechanisms underlying this phenomenon remain unknown. In the present study, we investigated the signaling pathways involved in the antidepressant action of amitriptyline using an in vitro model involving Cx43-knockdown astrocytes. We found that amitriptyline potentiated the expression of brain-derived neurotrophic factor (BDNF), a key neurotrophic factor, in Cx43-knockdown astrocytes. This potentiation was mediated by the activation of Gq protein-coupled lysophosphatidic acid (LPA) receptors, a pathway that was sensitized by Cx43 downregulation. We further demonstrated that this signaling cascade involved the activation of Protein Kinase C (PKC) δ and transcription factor NF-κB, but not the conventional BDNF transcription factor CREB. We propose that Cx43 downregulation enhances the antidepressant effect of amitriptyline by specifically engaging the Gq-PKCδ-NF-κB pathway. These findings suggest that Cx43 downregulation in astrocytes, which has been considered a pathological feature of depression, may paradoxically contribute to the therapeutic efficacy of antidepressants by sensitizing a specific signaling pathway. Our study provides new insights into the molecular mechanism of antidepressant action and highlights the potential role of astrocytic Cx43 in modulating therapeutic responses. Show less

The integrated stress response (ISR) has been implicated in cognitive decline associated with ageing and neurodegenerative diseases. Pharmacological inhibition of the ISR using the small-molecule ISRIB has demonstrated promising neuroprotective effects in several preclinical models. However, its potential therapeutic value in vascular cognitive impairment (VCI) remains largely unexplored. Here, we established a modified permanent bilateral carotid occlusion (2-VO) rat model of VCI and investigated the therapeutic potential of the ISRIB via microinjection in hippocampal dentate gyrus (DG). VCI rats exhibited elevated expression of vascular endothelial growth factor (VEGF), cluster of differentiation 34 (CD34), ionized calcium-binding adapter molecule 1 (Iba1), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6), indicating successful establishment of the model. Behavioral assessments revealed that VCI rats exhibited impaired spatial, working, and recognition memory. Bioinformatic analysis highlighted ISR pathway activation in VCI. Furthermore, elevated phosphorylated eukaryotic initiation factor 2 alpha (p-eIF2α) and activating transcription factor 4 (ATF4) protein levels in the DG confirmed ISR activation in the DG of VCI rats. VCI also reduced neuronal integrity, as evidenced by decreased Nissl body density. ISRIB treatment significantly improved cognitive performance, suppressed ATF4 expression, enhanced puromycin-labeled protein synthesis, and restored phosphorylated cAMP response element-binding protein (p-CREB) and brain-derived neurotrophic factor (BDNF) signaling. Notably, ISRIB increased c-fos activation and upregulated synaptophysin and postsynaptic density protein 95 (PSD95) expression in the DG of VCI rats, indicating enhanced neuronal activity and synaptic function. Our results indicate that ISR activation contributes to hippocampal-dependent memory impairment in VCI. ISRIB effectively restores synaptic function and cognition, underscoring its therapeutic value and translational potential in treating VCI. Show less