NeuroMolecular Medicine最新文献

Mitochondrial diseases (MDs) are heterogeneous multisystemic disorders often caused by genetic defects in either nuclear or mitochondrial DNA. Although next-generation sequencing technologies have dramatically expanded the number of variants associated with these diseases, many remain variants of unknown significance (VUS). This review explores the utility of zebrafish (Danio rerio) as a vertebrate model system for studying mitochondrial dysfunction, with a focused analysis on the application of morpholino oligonucleotides (MOs) to functionally characterize and interpret VUS. MO-induced knockdown produces a transient suppression of target genes during zebrafish early development, recapitulating key MD phenotypes. Furthermore, rescue experiments involving co-injection of MO and either wild-type or mutant mRNA have proven useful to functionally assess the pathogenicity of specific variants. Specifically, while wild-type mRNA rescues the morphant phenotype, failure of mutant mRNA to do so confirms the variant's pathogenic effect. This approach has successfully linked previously uncharacterized genes to MD and helped reclassify ambiguous variants. The use of MO-based strategies in zebrafish remains a valuable tool for variant interpretation and functional validation, bridging the gap between genomic data and clinical action, and ultimately reducing the diagnostic odyssey. Overall, this review places MO knockdown and rescue assays in zebrafish as a robust and versatile platform to address functional genomics in MD research.

Alzheimer's disease (AD), an irreversible, degenerative disorder, affects the central nervous system. However, its accurate pathology remains unclear, and studies on treatment modalities are ongoing. Picroside II (PII) is an active compound in the medicinal herb Rhizoma coptis. It has strong effects, including antioxidation, anti-inflammatory, antiapoptotic, and neuroprotective effects. In this study, we analyzed how PII affects cognitive impairment in mice with AD and its underlying mechanism. PII at doses of 20 or 40 mg/kg was given to APP/PS1 mice through intraperitoneal injection for 2 months. Moreover, we carried out the Morris water maze test to evaluate cognitive function. Immunofluorescence analysis was performed to observe cortical Aβ plaque deposition, neuronal loss, and inflammatory cell expression. An enzyme-linked immunosorbent assay (ELISA) was performed to measure the levels of the cortical inflammatory factors tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β. Western blotting and quantitative polymerase chain reaction (qPCR) were performed to measure NLRP3, ASC, GSDMD, and caspase-1 expression. PII improved cognitive function, reduced Aβ plaque deposition and glial activation, and alleviated cortical neuronal loss in APP/PS1 mice. Furthermore, PII decreased the levels of cortical inflammatory factors (TNF-α, IL-6, and IL-1β). In addition, it suppressed NLRP3, ASC, GSDMD, and caspase-1 expression at the mRNA and protein levels. PII enhances the cognitive function of APP/PS1 mice by reducing inflammation and pyroptosis via the suppression of the NLRP3/caspase-1/GSDMD pathway. Therefore, PII is a candidate anti-AD therapeutic agent.

This study investigates the influence of sex on region-specific neural vulnerability following global cerebral ischemia using a Bilateral Common Carotid Artery Occlusion (BCCAo) mouse model that mimics severe ischemic brain stroke condition in humans. Comprehensive behavioral assessments, neuropathological analyses, and molecular profiling were conducted across multiple time points post-ischemia in male and female CD1 mice. Both sexes exhibited early motor deficits, cortical-striatal mitochondrial dysfunction, inflammation, and cell death at day 1, with gradual behavioral recovery. However, the hippocampus demonstrated a clear sex-specific divergence: males exhibited delayed yet prolonged inflammation, apoptotic cell death, and increased autophagy/mitophagy activity, while females were largely protected despite hypoxic and inflammatory gene expression. Molecular assays revealed prolonged upregulation of hypoxia-inducible factor 1α (HIF-1α), IL-1β, IL-6, TNF-α, and apoptotic markers in males, especially in the hippocampus, alongside increased expression of autophagy (Beclin-1, LC3-II, ATG7) and mitophagy (PINK1, BNIP3L) regulators and a shift in mitochondrial dynamics favoring fission.

The persistence of deleterious substances at lesion sites severely impedes neuronal survival and axonal regeneration following central nervous system (CNS) injury or in neurodegenerative disorders. Therefore, clearing these harmful components and establishing a regeneration-permissive microenvironment are crucial for functional recovery. In this study, primary olfactory ensheathing cells (OECs) isolated from adult SD rats were pharmacologically treated with fisetin, a pharmacological agent. To model CNS injury conditions, neural debris was generated through mechanical disruption of primary neural cells. Neurons exposed to this hostile environment were then treated with conditioned medium from fisetin-activated OECs. Subsequent assessments using qRT-PCR, Western blot, CCK-8 assays, immunofluorescence, and ELISA revealed that fisetin significantly enhanced OEC activation, increasing proliferation and viability. Critically, fisetin-treated OECs markedly mitigated debris-induced neurotoxicity, thereby promoting neuronal survival and neurite outgrowth, which was associated with the upregulated anti-inflammatory cytokines (IL-4, IL-10, TGF-β) and neurotrophic factors (BDNF, GDNF, NGF). Mechanistically, fisetin-activated OECs facilitated neuronal growth via the PI3K/Akt/CREB pathway, suggesting that fisetin potentiates OEC-mediated neuroprotection and neurite regeneration in degenerative environments. These findings may highlight the therapeutic potential of combining OECs therapy with fisetin for CNS injuries and neurodegenerative diseases.

The composition of intestinal microbial communities plays a crucial role in maintaining immune homeostasis, influencing both innate and adaptive immune responses. Growing evidence indicates that bidirectional communication between gut bacteria and host immune cells contributes to the development of autoimmune diseases. Disruptions in microbial diversity, known as dysbiosis, are linked to an increased susceptibility to autoimmune disorders such as rheumatoid arthritis (RA), multiple sclerosis (MS), and lupus erythematosus. This review examines the mechanistic connections between microbial dysregulation and abnormal immune activation, focusing on key signaling pathways. Pathways such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), Janus kinase/signal transducers and activators of transcription (JAK/STAT), and Toll-like receptor (TLR) networks act as immunological gatekeepers, and their dysregulation-induced by microbial metabolites or shifts in microbial composition-can lead to chronic inflammation and the breakdown of self-tolerance. Additionally, bacterial fermentation products, including short-chain fatty acids (SCFAs), exert immunomodulatory effects by influencing T-cell differentiation and cytokine profiles. Emerging therapeutic strategies targeting microbial restoration, such as precision probiotics, microbiota transplantation, and tailored nutritional interventions, aim to restore immune balance. This review underscores the gut microbiota as a dynamic regulator of immune signaling.

Hypertension is a significant risk factor for cognitive decline and dementia, yet the underlying mechanisms linking hypertension to cognitive impairments remain poorly understood. Central acetylcholine (ACh) receptors play a crucial role in the regulation of cognitive function. This study aimed to investigate the effects of hypertension on the mRNA levels of ACh receptors in the hippocampus and medial prefrontal cortex (mPFC). We induced hypertension in mice by continuous Angiotensin II (Ang II) infusion and evaluated cardiovascular parameters as well as cognitive performance using behavioral tests, including the Y-maze, object location task, and Morris water maze. Our findings indicated a significant increase in systolic blood pressure (SBP) and heart weight in Ang II-treated mice without affecting body weight or heart rate. Behavioral assessments revealed notable cognitive deficits characterized by reduced alternation in the Y-maze, impaired object recognition, and increased escape latency in the Morris water maze. Furthermore, quantitative real-time PCR analysis demonstrated reductions in the mRNA levels of muscarinic ACh receptor (Chrm1) and nicotinic ACh receptors (Chrnα4, Chrnα7 and Chrnβ2) in the hippocampus as well as Chrm1, Chrnα5 and Chrnα7 in the mPFC. In addition, correlations were observed between SBP and mRNA levels of labile ACh receptors in mice. Our findings elucidate the critical relationship between hypertension-induced cognitive impairment and the altered mRNA levels of ACh receptors, providing a foundation for future research aimed at restoring cholinergic function and developing therapeutic strategies to mitigate cognitive decline in hypertensive patients.

Autoimmune diseases occur when the immune system mistakenly attacks the body's own tissues, affecting millions of people and often requiring long-term treatment. Current therapies, such as immunosuppressants and biologics, help manage symptoms but can cause serious side effects. A promising new approach involves engineered microbiota-a method that modifies gut bacteria to influence immune function and potentially ease autoimmune conditions. The gut microbiome is crucial in regulating immunity, and imbalances in its composition have been linked to diseases, such as rheumatoid arthritis (RA), multiple sclerosis (MS), and inflammatory bowel disease (IBD). Engineered microbiota works by altering microbial communities, either by adding new strains, genetically modifying existing bacteria, or using carefully selected groups of microbes to control inflammation and immune responses. Recent studies in both animal models and human trials suggest this approach could help restore immune tolerance, reduce inflammation, and repair the gut barrier. However, challenges remain, including ensuring safety, long-term effectiveness, and meeting regulatory standards. Despite being in its early stages, engineered microbiota holds great promise as a future treatment for autoimmune diseases, paving the way for more precise and personalized therapies that leverage the power of the microbiome to improve health.

It is now widely accepted that the development of neurodegenerative diseases depends on and affects many pathological processes, both in the brain and the periphery. Inflammatory, cardiovascular, metabolic, cerebrovascular, autoimmune, and other environmental factors have been extensively studied and shown to contribute notably to the onset, pathogenesis, and clinical outcome of Alzheimer´s disease (AD), Parkinson´s disease (PD), cerebral amyloid angiopathy (CAA), multiple sclerosis, and other neurological disorders. Likewise, AD-induced changes in other tissues outside the central nervous system, such as abnormalities observed in the liver, spleen, or lungs, have been documented and extensively studied, leading to a better understanding of brain-periphery crosstalk in neurodegenerative diseases and the development of novel diagnostic and therapeutic approaches. In this study, we documented striking differences in the periphery in two frequently used, well-established APP transgenic mouse models of AD: 3xTg-AD mice, harboring three human genes (APP, tau, and Psen1), and Tg-SwDI mice, expressing human APP with the Swedish and vasculotropic Dutch/Iowa mutations in the brain. We documented splenomegaly, immunoglobulin-associated spleen amyloidosis, and an increase in the percentage of neutrophils in the spleen and macrophages in the liver in 3xTg-AD mice but not in age-matched Tg-SwDI mice, which are commonly used as an AD/CAA model. Our data suggest that the results observed in any transgenic mouse strain should be taken into account with caution. A detailed knowledge of pathological characteristics recapitulated in a particular strain can help to determine which mice are more appropriate for studying a specific mechanism or therapeutic approach.

The recently discovered family of heat-resistant obscure (Hero) proteins represents a novel class with chaperone-like activity and unique protective properties. These proteins may contribute to cellular survival in ischemic stroke (IS) conditions. Herein, we aimed to investigate the expression dynamics of six Hero genes during the acute and subacute phases of IS. Peripheral blood samples were collected from IS patients in the acute (day 1, n = 47) and subacute (day 7, n = 41) phases, along with healthy controls (n = 42). Gene expression was assessed via quantitative PCR. Statistical analysis included group comparisons, multivariate regression modelling, and correlation analysis. In the acute phase, C9orf16 (P = 0.006), C11orf58 (P = 0.00001), and SERBP1 (P = 0.006) were significantly downregulated compared to controls. By day 7, SERBP1 expression normalized, while C9orf16 (P = 0.002) and C11orf58 (P = 0.0004) remained downregulated. Multivariate regression identified C11orf58 expression as a potential biomarker of IS. Expression levels of SERBP1 and C11orf58 negatively correlated with infarct size during both the acute (R = - 0.59, P = 0.00012; R = - 0.49, P = 0.004) and subacute phases (R = - 0.54, P = 0.0024; R = - 0.44, P = 0.032). eQTL analysis showed that SERBP1 SNPs were associated with reduced expression only in controls. Our findings underscore the potential relevance of Hero proteins as biomarkers or therapeutic targets in IS, warranting further investigation into their mechanistic involvement in neuroprotection and recovery.

Long-term hyperglycemia and insulin dysfunction deteriorate peripheral nerve functions, leading to sensory loss, spontaneous pain, and hypersensitivity (i.e., allodynia and hyperalgesia). Evidence indicates glucose-induced upregulation of the Wnt/β-catenin mechanism in diabetic peripheral neuropathy (DPN). Eriodictyol (Ed) has shown protective effects against glucotoxicity. The present study explored the bioactivity of Ed in streptozotocin (STZ) induced DPN and the role of the Wnt/β-catenin pathway. Ed or gabapentin (Gpn), or methyl vanillate (MV) was administered in Wistar rats for 4 weeks, starting 6 weeks after STZ administration. Ed ameliorated the mean body weight and mitigated polydipsia and polyphagia in DPN rats. The data indicated that Ed attenuated hyperglycemia, glycosylated hemoglobin (HbA1c) levels, and HOMA-IR, and enhanced circulating insulin levels and HOMA-β against STZ-induced DPN. MV (Wnt/β-catenin activator) caused a significant increase in STZ-induced hyperglycemia, HbA1c, HOMA-IR, and further decreased the insulin levels and HOMA-β in STZ-treated rats. Ed attenuated oxidative stress, inflammatory expression, level of advanced glycation end products, and nuclear factor kappa B in the sciatic nerve of STZ-treated neuropathic rats, and MV further potentiated these markers triggered by STZ. Interestingly, Ed and Gpn attenuated mRNA expression of Wnt1/β-catenin in the sciatic nerve of neuropathic rats. Hyperalgesia and allodynia were significantly ameliorated in Ed or Gpn-treated rats against DPN. Furthermore, Ed ameliorated the biochemical biomarkers, histopathological characteristics, and nociceptive-like responses in STZ and MV-treated rats. It is concluded that Ed can alleviate the pathogenic course of DPN. Wnt/β-catenin pathway might be involved in the eriodyctiol-triggered mitigation of nociceptive-like responses in diabetic rats.