Mouse spermatogenesis entails the maintenance and self-renewal of spermatogonial stem cells (SSCs), which require a complex web-like signaling network transduced by various cytokines. Although brain-derived neurotrophic factor (BDNF) is expressed in Sertoli cells in the testis, and its receptor tropomyosin receptor kinase B (TrkB) is expressed in the spermatogonial population containing SSCs, potential functions of BDNF for spermatogenesis have not been uncovered. Here, we generate BDNF conditional knockout mice and find that BDNF is dispensable for in vivo spermatogenesis and fertility. However, in vitro , we reveal that BDNF -deficient germline stem cells (GSCs) exhibit growth potential not only in the absence of glial cell line-derived neurotrophic factor (GDNF), a master regulator for GSC proliferation, but also in the absence of other factors, including epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and insulin. GSCs grown without these factors are prone to differentiation, yet they maintain expression of promyelocytic leukemia zinc finger ( Plzf ), an undifferentiated spermatogonial marker. Inhibition of phosphoinositide 3-kinase (PI3K), mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK), and Src pathways all interfere with the growth of BDNF-deficient GSCs. Thus, our findings suggest a role for BDNF in maintaining the undifferentiated state of spermatogonia, particularly in situations where there is a shortage of growth factors.
Animals ; Male ; Brain-Derived Neurotrophic Factor/genetics* ; Spermatogonia/cytology* ; Mice ; Spermatogenesis/genetics* ; Mice, Knockout ; Cell Differentiation ; Glial Cell Line-Derived Neurotrophic Factor/genetics* ; Promyelocytic Leukemia Zinc Finger Protein/genetics* ; Cell Survival/physiology* ; Signal Transduction/physiology* ; Cell Proliferation/physiology*

OBJECTIVES: To investigate whether mesenchymal stem cell-derived exosomes (MSC-Exo) alleviate white matter damage (WMD) in neonatal rats by targeting the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3). METHODS: Three-day-old Sprague-Dawley rats were randomly assigned to four groups: Sham, hypoxia-ischemia (HI), MSC-Exo, and MCC950 (NLRP3 inhibitor) (n=24 per group). The WMD model was established by unilateral common carotid artery ligation combined with hypoxia. Exosomes (1×10⁸ particles/μL) were transplanted into the lateral ventricle using stereotaxic guidance. Fourteen days after modeling, hematoxylin-eosin staining was used to observe pathological changes in brain tissue, and transmission electron microscopy was used to assess myelinated axons. Western blotting was performed to detect the expression of myelin basic protein (MBP), NLRP3, caspase-1, and interleukin-1β (IL-1β). Immunohistochemistry was used to measure NLRP3, caspase-1, and IL-1β expression. Twenty-eight days post-modeling, behavioral changes were evaluated using the Morris water maze. RESULTS: In the HI group, marked inflammatory cell infiltration, extensive vacuolation, and decreased numbers of myelinated axons were observed compared to the Sham group. The MSC-Exo group showed reduced inflammatory infiltration, fewer vacuoles, and increased myelinated axons compared to the HI group, while the MCC950 group showed nearly normal cell morphology. Compared to the Sham group, the HI group exhibited decreased MBP expression, fewer platform crossings, shorter time in the target quadrant, increased expression of NLRP3, caspase-1, and IL-1β, and longer escape latency (all P<0.05). Compared to the HI group, the MSC-Exo and MCC950 groups showed increased MBP expression, more platform crossings, longer target quadrant stay, and reduced NLRP3, caspase-1, and IL-1β expression, as well as shorter escape latency (all P<0.05). CONCLUSIONS MSC-Exo may attenuate white matter damage in neonatal rats by targeting the NLRP3 inflammasome and promoting oligodendrocyte maturation.
Animals ; NLR Family, Pyrin Domain-Containing 3 Protein/antagonists & inhibitors* ; Rats, Sprague-Dawley ; White Matter/pathology* ; Inflammasomes/physiology* ; Rats ; Animals, Newborn ; Mesenchymal Stem Cells ; Interleukin-1beta/analysis* ; Male ; Caspase 1/analysis* ; Hypoxia-Ischemia, Brain/therapy* ; Myelin Basic Protein/analysis*

OBJECTIVES: To investigate whether human umbilical cord mesenchymal stem cells (HUC-MSCs) play protective effects against white matter injury (WMI) in neonatal rats via activation of the nuclear factor-erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1)/heme oxygenase-1 (HO-1) signaling pathway. METHODS: A neonatal WMI model was established in 3-day-old Sprague-Dawley rats by unilateral common carotid artery ligation combined with hypoxia. The study comprised two parts. (1) Rats were randomized into sham, hypoxia-ischemia (HI), and HUC-MSC groups (n=36 per group); brain tissues were collected at 7, 14, and 21 days after modeling. (2) Rats were randomized into sham, HI, HUC-MSC, and HUC-MSC+ML385 (Nrf2 inhibitor) groups (n=12 per group); tissues were collected 14 days after modeling. Hematoxylin-eosin staining assessed histopathology, and Luxol fast blue staining evaluated myelination. Immunohistochemistry examined the localization and expression of Nrf2, myelin basic protein (MBP), and proteolipid protein (PLP). Immunofluorescence assessed synaptophysin (SYP) and postsynaptic density-95 (PSD-95). Western blotting quantified Nrf2, Keap1, HO-1, SYP, PSD-95, MBP, and PLP. Spatial learning and memory were evaluated by the Morris water maze. RESULTS: At 7, 14, and 21 days after modeling, the sham group showed intact white matter, whereas the HI group exhibited white matter disruption, cellular vacuolation, and disorganized nerve fibers. These pathological changes were attenuated in the HUC-MSC group. Compared with the HI group, the HUC-MSC group showed increased Nrf2 immunopositivity and protein levels, increased HO-1 protein levels, and decreased Keap1 protein levels (P<0.05). Compared with the HI group, the HUC-MSC group had higher SYP and PSD-95 immunofluorescence intensities and protein levels, higher MBP and PLP positivity and protein levels, increased mean optical density of myelin, more platform crossings, and longer time in the target quadrant (all P<0.05). These improvements were reduced in the HUC-MSC+ML385 group compared with the HUC-MSC group (P<0.05). CONCLUSIONS HUC-MSCs may promote oligodendrocyte maturation and synaptogenesis after neonatal WMI by activating the Nrf2/Keap1/HO-1 pathway, thereby improving spatial cognitive function.
NF-E2-Related Factor 2/physiology* ; Animals ; Rats, Sprague-Dawley ; Signal Transduction/physiology* ; Humans ; Rats ; White Matter/pathology* ; Kelch-Like ECH-Associated Protein 1/physiology* ; Umbilical Cord/cytology* ; Heme Oxygenase-1/physiology* ; Animals, Newborn ; Male ; Mesenchymal Stem Cell Transplantation ; Heme Oxygenase (Decyclizing)/physiology* ; Mesenchymal Stem Cells/physiology* ; Female ; Hypoxia-Ischemia, Brain

Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in children. Growing evidence links ADHD to gut microbiota dysbiosis, positioning the microbiota-gut-brain axis as a new focus of childhood ADHD research. This review systematically elucidates the association between gut dysbiosis and childhood ADHD and analyzes key mechanisms by which the microbiota-gut-brain axis regulates bidirectional gut-brain communication through multiple pathways. It highlights recent findings on microbiota-targeted strategies to improve ADHD symptoms and discusses therapeutic prospects, with the aim of exploring new avenues for early intervention and treatment in children with ADHD.
Humans ; Attention Deficit Disorder with Hyperactivity/microbiology* ; Gastrointestinal Microbiome/physiology* ; Child ; Brain/physiology* ; Dysbiosis

In the era of big data, neuroimaging and algorithmic analyses have propelled brain science research and brain mapping. Acupuncture, widely recognized as an effective surface stimulation therapy, has demonstrated therapeutic efficacy for various brain conditions such as stroke and depression. However, the mechanisms linking acupuncture to brain function and its modulatory effects on brain activity require systematic exploration. Additionally, there is an urgent need to scientifically reinterpret traditional meridian theory and enhance its clinical applicability. Therefore, we propose the initiative of constructing a "brain mapping atlas of meridian, collateral and body surface stimulation" to explore the patterns linking the therapeutic effects of stimulating the twelve meridians, eight extraordinary vessels, divergent channels, collateral channels, sinew channels, and skin regions to brain function. This initiative aims to provide a scientific interpretation of traditional Chinese medicine meridian theory and enhance its practical applicability. This paper begins by reviewing the current state of brain mapping. It then summarizes existing research on the relationship between acupuncture and the brain, highlighting the necessity of constructing this atlas. The paper further analyzes the methodologies and technical challenges involved. Finally, the potential applications of the brain mapping atlas of meridian, collateral and body surface stimulation, and its main significance in advancing traditional meridian theory to keep pace with the times are prospected.
Humans ; Acupuncture Therapy ; Meridians ; Big Data ; Brain/physiology* ; Brain Mapping

The correlation between meridians and zangfu organs is one of the core contents of the theory of zangfu organs and meridians, which has significant research value and clinical application potential. In this paper, the research literature on correlation between meridians and zangfu organs in the past five years is sorted out and summarized, and it is found that more clinical application basis is added in meridian-diagnosis, and a new situation of high-quality evidence-based medicine is opened in the aspect of meridian-treatment. In terms of internal connection and biological mechanism, the neurobiological characteristics and regulatory mechanism represented by "heart meridian-heart" are illustrated. The research model of the relationship between the meridians-zangfu organs and the brain, which combines the functional connection of the brain network in clinic and the basic neural circuit mechanism under the premise of the "effect law", is clearly proposed.
Meridians ; Humans ; Brain/physiology*

Electroencephalography (EEG) and magnetic resonance imaging (MRI), as neuroimaging technologies, provided objective and visualized technical tools for analyzing the brain effect mechanisms of acupuncture and moxibustion from the perspectives of brain structure, function, metabolism, and hemodynamics. The advancement of artificial intelligence (AI) algorithms can compensate for issues such as the large and scattered nature of neuroimaging data, inconsistent quality, and high heterogeneity of image information. The integration of AI with neuroimaging can facilitate individualized, intelligent, and precise prediction of acupuncture and moxibustion effects, enable intelligent classification of differential acupuncture responses, and identify brain activation patterns. This paper focuses on EEG and MRI, analyzing how machine learning and deep learning optimize multimodal neuroimaging data and their applications in the study of acupuncture and moxibustion brain effects mechanisms. Furthermore, it highlights current research gaps and limitations to provide insights for future studies on acupuncture brain effects mechanisms.
Humans ; Acupuncture Therapy ; Brain/physiology* ; Moxibustion ; Neuroimaging/methods* ; Artificial Intelligence ; Magnetic Resonance Imaging ; Electroencephalography

Gliomas are the most common primary neuroepithelial tumors of the central nervous system in adults, of which glioblastoma is the deadliest subtype. Apart from the intrinsically indestructible characteristics of glioma (stem) cells, accumulating evidence suggests that the tumor microenvironment also plays a vital role in the refractoriness of glioblastoma. The primary functions of platelets are to stop bleeding and regulate thrombosis under physiological conditions. Furthermore, platelets are also active elements that participate in a variety of processes of tumor development, including tumor growth, invasion, and chemoresistance. Glioma cells recruit and activate resting platelets to become tumor-educated platelets (TEPs), which in turn can promote the proliferation, invasion, stemness, and chemoresistance of glioma cells. TEPs can be used to obtain genetic information about gliomas, which is helpful for early diagnosis and monitoring of therapeutic effects. Platelet membranes are intriguing biomimetic materials for developing efficacious drug carriers to enhance antiglioma activity. Herein, we review the recent research referring to the contribution of platelets to the malignant characteristics of gliomas and focusing on the molecular mechanisms mediating the interaction between TEPs and glioma (stem) cells, as well as present the challenges and opportunities in targeting platelets for glioma therapy.
Humans ; Glioma/metabolism* ; Blood Platelets/physiology* ; Brain Neoplasms/pathology* ; Tumor Microenvironment

Inflammatory bowel disease (IBD) is an idiopathic intestinal inflammatory condition with chronic and relapsing manifestations and is characterized by a disturbance in the interplay between the intestinal microbiota, the gut, and the brain. The microbiota-gut-brain axis involves interactions among the nervous system, the neuroendocrine system, the gut microbiota, and the host immune system. Increasing published data indicate that psychological stress exacerbates the severity of IBD due to its negative effects on the microbiota-gut-brain axis, including alterations in the stress response of the hypothalamic-pituitary-adrenal (HPA) axis, the balance between the sympathetic nervous system and vagus nerves, the homeostasis of the intestinal flora and metabolites, and normal intestinal immunity and permeability. Although the current evidence is insufficient, psychotropic agents, psychotherapies, and interventions targeting the microbiota-gut-brain axis show the potential to improve symptoms and quality of life in IBD patients. Therefore, further studies that translate recent findings into therapeutic approaches that improve both physical and psychological well-being are needed.
Humans ; Inflammatory Bowel Diseases/metabolism* ; Stress, Psychological/microbiology* ; Gastrointestinal Microbiome/physiology* ; Brain/metabolism* ; Hypothalamo-Hypophyseal System ; Pituitary-Adrenal System ; Animals

Brain science is the frontier of modern science, and new advances have been made in brain-like designs and brain-computer interfaces to simulate or develop brain functions. However, given that the brain is hermetically sealed within the skull, exploration and deciphering of the brain structure and functions are limited. Growing evidence suggests that the gut is not just a digestive organ. It not only provides essential nutrients and electrolytes for brain neurodevelopment and the maintenance of brain function, but it also transmits external environmental and intestinal wall signals from the intestinal lumen to the central nervous system through multiple pathways to regulate brain activity, function, and structure. A variety of gut-brain interaction pathways have been identified, including neural pathways, neuroimmune signaling, endocrine pathways, and biochemical messengers produced by gut microbes. Gut microbes interact with food and the gut to modulate gut-brain communication. The gut's important role and potential in neurodevelopment, maintenance of normal function, and disease development make it an increasingly important area of research in brain science and neuropsychiatric disorders. The gut's unique role in brain functions and its accessibility for research (compared to direct brain studies) establish it as a critical gate to understanding the mysteries of brain science. Crucially, intestinal nutrients and microbes provide two unique keys to unlock this gate-enabling neural regulation and novel treatments for neuropsychiatric diseases.
Humans ; Brain/physiology* ; Animals ; Gastrointestinal Microbiome/physiology* ; Gastrointestinal Tract/microbiology*