{"title":"Age-related alterations in functional and structural networks in the brain in macaque monkeys.","authors":"Kazuya Ouchi, Shinya Yamamoto, Makoto Obara, Yasuko Sugase-Miyamoto, Tomokazu Tsurugizawa","doi":"10.3389/fnana.2025.1495735","DOIUrl":"10.3389/fnana.2025.1495735","url":null,"abstract":"<p><p>Resting-state networks (RSNs) have been used as biomarkers of brain diseases and cognitive performance. However, age-related changes in the RSNs of macaques, a representative animal model, are still not fully understood. In this study, we measured the RSNs in macaques aged 3-20 years and investigated the age-related changes from both functional and structural perspectives. The proportion of structural connectivity in the RSNs relative to the total fibers in the whole brain significantly decreased in aged macaques, whereas functional connectivity showed an increasing trend with age. Additionally, the amplitude of low-frequency fluctuations tended to increase with age, indicating that resting-state neural activity may be more active in the RSNs may increase with age. These results indicate that structural and functional alterations in typical RSNs are age-dependent and can be a marker of aging in the macaque's brain.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1495735"},"PeriodicalIF":2.1,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11975867/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frontiers in NeuroanatomyPub Date : 2025-03-25eCollection Date: 2025-01-01DOI: 10.3389/fnana.2025.1547165
Edgar Buloz-Osorio, Marisa Ortega-Sánchez, Miguel B Royo-Salvador, Alfonso Rodríguez-Baeza
{"title":"Morphological analysis of the filum terminale and detailed description of the distal filum terminale externum: a cadaveric study.","authors":"Edgar Buloz-Osorio, Marisa Ortega-Sánchez, Miguel B Royo-Salvador, Alfonso Rodríguez-Baeza","doi":"10.3389/fnana.2025.1547165","DOIUrl":"10.3389/fnana.2025.1547165","url":null,"abstract":"<p><p>This observational, descriptive anatomical cadaveric study aimed to identify, characterize, and analyze the morphometric parameters of the filum terminale (FT) and macroscopically describe the distal insertion of the FTE. The FT is a complex, three-dimensional, fibro-cellular structure of connective tissue and glial cells, extending from the conus medullaris (CM) to the dural sac (DS) and coccyx. It is divided into two segments: an intradural filum terminale internum (FTI) and extradural filum terminale externum (FTE). Few studies have comprehensively addressed its morphometric characteristics in the last decades. Thirty-eight embalmed (M = 16, F = 22) human cadavers were examined to determine the CM-FTI and DS-FTE vertebral levels and FT, FTI, and FTE lengths and widths. FTI and FTE segmental diameters, correlations, gross characteristics, tension, and mobility <i>in situ</i> and <i>ex vivo</i> were assessed. FTE distal insertion is thoroughly described. FT, FTI, and FTE mean lengths were 254.32 mm (±26.46), 152.75 mm (±22.02), and 106.64 mm (±12.21), respectively. The CM-FTI junction was observed at the L1-L2 disk space (32.1%), DS-FTE fusion in the upper third of S2 (39.3%), and FTI-DS fusion in the DS midline (46.4%). FT length and FTI, FTE lengths were directly correlated, as were all FTI diameters. FT gross characteristics were an irregular surface (71.4%), bright hue (57.1%), macroscopic FTI-CM contrast (64.3%), filiform shape (60.7%), and movement-resistance (53.6%). The FTE exhibited a flattened shape (64.3%), immobility (60.7%), distal insertion at Cx1 (67.8%) and one distal strand (60.7%). FTI segments ≥ 2 mm were uncommon (21.4%). The FTE distal insertion is variable, inserting as strands, with vascular tissue surrounding it. A distal coccygeal venous plexus and single or multiple strand-like insertions of the distal FTE are for the first time described in detail. Discrepancies in the morphometric parameters of the FT between studies highlight the need for standardized protocols, especially given the FT's anatomic-clinical importance and potential role as a neural progenitor niche. We provide a comprehensive basis for future standardized morphometric analyses, acknowledging the limitations of embalmed cadaveric studies.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1547165"},"PeriodicalIF":2.1,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11975916/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143811021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frontiers in NeuroanatomyPub Date : 2025-03-19eCollection Date: 2025-01-01DOI: 10.3389/fnana.2025.1553952
Lorena Morales, Ester Desfilis, Loreta Medina
{"title":"Development of catecholaminergic neurons of Otp-lineage in the medial extended amygdala and related forebrain centers.","authors":"Lorena Morales, Ester Desfilis, Loreta Medina","doi":"10.3389/fnana.2025.1553952","DOIUrl":"10.3389/fnana.2025.1553952","url":null,"abstract":"<p><p>Catecholaminergic (CA) neurons of the medial extended amygdala, preoptic region and adjacent alar hypothalamus have been involved in different aspects of social behavior, as well as in modulation of homeostasis in response to different stressors. Previous data suggested that at least some CA neurons of the medial extended amygdala could originate in a hypothalamic embryonic domain that expresses the transcription factor Otp. To investigate this, we used Otp-eGFP mice (with permanent labeling of GFP in Otp cells) to analyze coexpression of GFP and tyrosine hydroxylase (TH) throughout ontogenesis by way of double immunofluorescence. Our results provide evidence that some forebrain CA cells belong to the Otp lineage. In particular, we found small subpopulations of TH cells that coexpress GFP within the medial extended amygdala, the periventricular preoptic area, the paraventricular hypothalamus, the periventricular hypothalamus, as well as some subdivisions of the basal hypothalamus. In some of the Otp cells, such as those of extended amygdala, the expression of TH appears to be transitory, in agreement with previous studies. The results open interesting questions about the role of these Otp versus non-Otp catecholaminergic subpopulations during development, network integration and in modulation of different functions, including homeostasis and social behaviors.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1553952"},"PeriodicalIF":2.1,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11961924/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143772059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frontiers in NeuroanatomyPub Date : 2025-03-12eCollection Date: 2025-01-01DOI: 10.3389/fnana.2025.1557214
Eneritz López-Muguruza, Carla Peiró-Moreno, Fernando Pérez-Cerdá, Carlos Matute, Asier Ruiz
{"title":"Del Río Hortega's insights into oligodendrocytes: recent advances in subtype characterization and functional roles in axonal support and disease.","authors":"Eneritz López-Muguruza, Carla Peiró-Moreno, Fernando Pérez-Cerdá, Carlos Matute, Asier Ruiz","doi":"10.3389/fnana.2025.1557214","DOIUrl":"10.3389/fnana.2025.1557214","url":null,"abstract":"<p><p>Pío Del Río Hortega (1882-1945) was a giant of modern neuroscience and perhaps the most impactful member of Cajal's School. His contributions to clarifying the structure of the nervous system were key to understanding the brain beyond neurons. He uncovered microglia and oligodendrocytes, the latter until then named mesoglia. Most importantly, the characterization of oligodendroglia subtypes he made has stood the omics revolution that added molecular details relevant to comprehend their biological properties. Astounding as it may seem on today's eyes, he postulated a century ago that oligodendrocytes provide trophic support to axons, an idea that is now beyond doubt and under scrutiny as dysfunction at the axon-myelin unit is key to neurodegeneration. Here, we revised recent key advancements in oligodendrocyte biology that shed light on Hortega's ideas a century ago.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1557214"},"PeriodicalIF":2.1,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11936973/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143718626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frontiers in NeuroanatomyPub Date : 2025-03-12eCollection Date: 2025-01-01DOI: 10.3389/fnana.2025.1532900
Doriane Hazart, Marwa Moulzir, Brigitte Delhomme, Martin Oheim, Clément Ricard
{"title":"Imaging the enteric nervous system.","authors":"Doriane Hazart, Marwa Moulzir, Brigitte Delhomme, Martin Oheim, Clément Ricard","doi":"10.3389/fnana.2025.1532900","DOIUrl":"10.3389/fnana.2025.1532900","url":null,"abstract":"<p><p>The enteric nervous system (ENS) has garnered increasing scientific interest due to its pivotal role in digestive processes and its involvement in various gastrointestinal and central nervous system (CNS) disorders, including Crohn's disease, Parkinson's disease, and autism. Despite its significance, the ENS remains relatively underexplored by neurobiologists, primarily because its structure and function are less understood compared to the CNS. This review examines both pioneering methodologies that initially revealed the intricate layered structure of the ENS and recent advancements in studying its three-dimensional (3-D) organization, both in fixed samples and at a functional level, <i>ex-vivo</i> or <i>in-vivo</i>. Traditionally, imaging the ENS relied on histological techniques involving sequential tissue sectioning, staining, and microscopic imaging of single sections. However, this method has limitations representing the full complexity of the ENS's 3-D meshwork, which led to the development of more intact preparations, such as whole-mount preparation, as well as the use of volume imaging techniques. Advancements in 3-D imaging, particularly methods like spinning-disk confocal, 2-photon, and light-sheet microscopies, combined with tissue-clearing techniques, have revolutionized our understanding of the ENS's fine structure. These approaches offer detailed views of its cellular architecture, including interactions among various cell types, blood vessels, and lymphatic vessels. They have also enhanced our comprehension of ENS-related pathologies, such as inflammatory bowel disease, Hirschsprung's disease (HSCR), and the ENS's involvement in neurodegenerative disorders like Parkinson's (PD) and Alzheimer's diseases (AD). More recently, 2-photon or confocal <i>in-vivo</i> imaging, combined with transgenic approaches for calcium imaging, or confocal laser endomicroscopy, have opened new avenues for functional studies of the ENS. These methods enable real-time observation of enteric neuronal and glial activity and their interactions. While routinely used in CNS studies, their application to understanding local circuits and signals in the ENS is relatively recent and presents unique challenges, such as accommodating peristaltic movements. Advancements in 3-D <i>in-vivo</i> functional imaging are expected to significantly deepen our understanding of the ENS and its roles in gastrointestinal and neurological diseases, potentially leading to improved diagnostic and therapeutic strategies.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1532900"},"PeriodicalIF":2.1,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11937143/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143718627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frontiers in NeuroanatomyPub Date : 2025-03-07eCollection Date: 2025-01-01DOI: 10.3389/fnana.2025.1557961
Mohammed M Nakhal, Ayishal B Mydeen, Lydia K Yassin, Reem Almazrouei, Rasha Alkamali, Mahra Alsulaimi, Rawan I Elsaleh, Shamsa BaniYas, Shaikha Al Houqani, Farah Al-Marzooq, Maya Hassane, Roman Voitetskii, Yauhen Statsenko, Mushal Allam, Amal Akour, Mohammad I K Hamad
{"title":"Antibiotics-induced dysbiosis impacts dendritic morphology of adult mouse cortical interneurons.","authors":"Mohammed M Nakhal, Ayishal B Mydeen, Lydia K Yassin, Reem Almazrouei, Rasha Alkamali, Mahra Alsulaimi, Rawan I Elsaleh, Shamsa BaniYas, Shaikha Al Houqani, Farah Al-Marzooq, Maya Hassane, Roman Voitetskii, Yauhen Statsenko, Mushal Allam, Amal Akour, Mohammad I K Hamad","doi":"10.3389/fnana.2025.1557961","DOIUrl":"10.3389/fnana.2025.1557961","url":null,"abstract":"<p><strong>Introduction: </strong>A growing body of evidence suggests that the gut microbiome may contribute to changes in brain morphology. The microbiota-gut-brain axis (MGBA) has been shown to influence neurogenesis, axon myelination, and synapse structure. However, it remains unclear whether the MGBA can influence the morphology and density of inhibitory GABAergic interneurons. The aim of this study was to determine whether antibiotic-induced dysbiosis (AID) is associated with alterations in dendritic morphology of GABAergic inhibitory interneurons in the medial entorhinal cortex (mEC), somatosensory cortex (SSC), motor cortex (MC), and hippocampus (Hp).</p><p><strong>Methods: </strong>A cohort of six-month-old GAD-67-EGFP transgenic mice was treated with an antibiotic cocktail for two weeks, resulting in gut dysbiosis as validated by collecting stool samples at baseline and after treatment, then using next-generation sequencing of 16S ribosomal RNA.</p><p><strong>Results: </strong>The results demonstrate that the proposed model effectively exhibited the defining features of gut dysbiosis, including a significant reduction in microbiome diversity, expansion of pathobionts, and loss of beneficial microbes. The AID group showed alterations in density and morphology of GABAergic interneurons in different brain areas. The mean dendritic length and mean dendritic segments of the SSC and Hp were found to be significantly decreased, while no such decrease was observed in the mEC or MC. Furthermore, the density of interneurons was decreased in the mEC, Hp, and SSC areas, while no change was observed in the MC area.</p><p><strong>Discussion: </strong>The interneuron dysfunction plays a role in the pathogenesis of neurological disease. The findings of this study suggest that AID potentially influences the density and morphology of the interneurons, which may contribute to the development of neurological disorders.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1557961"},"PeriodicalIF":2.1,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11925899/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143691683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frontiers in NeuroanatomyPub Date : 2025-03-06eCollection Date: 2025-01-01DOI: 10.3389/fnana.2025.1535745
Siddhi S Ozarkar, Ridthi K R Patel, Tasmai Vulli, Carlee A Friar, Alain C Burette, Benjamin D Philpot
{"title":"Regional analysis of myelin basic protein across postnatal brain development of C57BL/6J mice.","authors":"Siddhi S Ozarkar, Ridthi K R Patel, Tasmai Vulli, Carlee A Friar, Alain C Burette, Benjamin D Philpot","doi":"10.3389/fnana.2025.1535745","DOIUrl":"10.3389/fnana.2025.1535745","url":null,"abstract":"<p><p>Healthy brain development hinges on proper myelination, with disruption contributing to a wide array of neurological disorders. Immunohistochemical analysis of myelin basic protein (MBP) is a fundamental technique for investigating myelination and related disorders. However, despite decades of MBP research, detailed accounts of normal MBP progression in the developing mouse brain have been lacking. This study aims to address this gap by providing a detailed spatiotemporal account of MBP distribution across 13 developmental ages from postnatal day 2 to 60. We used an optimized immunohistochemistry protocol to overcome the challenges of myelin's unique lipid-rich composition, enabling more consistent staining across diverse brain structures and developmental stages, offering a robust baseline for typical myelination patterns, and enabling comparisons with pathological models. To support and potentially accelerate research into myelination disorders, we have made >1,400 high-resolution micrographs accessible online under the Creative Commons license.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1535745"},"PeriodicalIF":2.3,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11922784/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frontiers in NeuroanatomyPub Date : 2025-02-19eCollection Date: 2025-01-01DOI: 10.3389/fnana.2025.1457557
Wigínio Gabriel Lira-Bandeira, Lílian Andrade Carlos Mendonça Batista, Andréa Silva Medeiros-Bandeira, Paulo Leonardo Araújo Góis Morais, Luiz Roberto Fernandes Pereira, Maria Lara Porpino Meiroz-Grilo, Jeferson Souza Cavalcante, Melquisedec Abiaré Dantas Santana, Ruthnaldo Rodrigues Melo Lima, Nicole Leite Galvão-Coelho, Fernando Vagner Lobo Ladd, Expedito Silva Nascimento
{"title":"Ayahuasca partially preserves striatal integrity in juvenile non-human primates exposed to chronic stress: evidence from stereological evaluation.","authors":"Wigínio Gabriel Lira-Bandeira, Lílian Andrade Carlos Mendonça Batista, Andréa Silva Medeiros-Bandeira, Paulo Leonardo Araújo Góis Morais, Luiz Roberto Fernandes Pereira, Maria Lara Porpino Meiroz-Grilo, Jeferson Souza Cavalcante, Melquisedec Abiaré Dantas Santana, Ruthnaldo Rodrigues Melo Lima, Nicole Leite Galvão-Coelho, Fernando Vagner Lobo Ladd, Expedito Silva Nascimento","doi":"10.3389/fnana.2025.1457557","DOIUrl":"10.3389/fnana.2025.1457557","url":null,"abstract":"<p><strong>Introduction: </strong>The striatum (St) integrates cognitive, motor, and limbic functions and plays a critical role in processing emotions, motivation, and rewards. It may undergo several morphophysiological changes in neuropsychiatric diseases. Depression, a complex psychiatric disorder, affects millions of people around the world and leads to an increased risk of suicide, decreased quality of life, and functional impairment. Conventional treatments require prolonged use, leading to drug resistance; thus, new treatments and therapeutic strategies have been widely studied. Ayahuasca results from the joint infusion of the <i>Banisteriopsis caapi</i> vine and Psychotria viridis leaves have psychoactive properties, and its use in depression has shown promising results. Our objective was to morphoquantitatively evaluate the effects of ayahuasca on the St in an already validated model of juvenile depression induced in a non-human primate.</p><p><strong>Methods: </strong>Six marmosets were divided into three groups of two animals each. One group was kept in family life (FG), and two groups were socially isolated (IG). Isolation was carried out by separating the animal from all others in the colony. One of the isolated groups received doses of ayahuasca tea (AG) 3 days before and two times during the isolation period, while the other groups received the same dose of placebo. After 13 weeks of experimentation, euthanasia, and transcardiac perfusion were performed. The brains were sectioned and stained with thionin using the Nissl method. We employed stereological techniques to assess the striatum and investigate potential alterations in neuronal volume in socially isolated animals treated with ayahuasca. Equidistant sections of the caudate and putamen were analyzed for all measurements and selected by systematic and uniform sampling.</p><p><strong>Results and discussion: </strong>Striatal neurons in the IG group exhibited significantly smaller volumes compared to those in the FG and AG groups. Our findings suggest that ayahuasca may prevent extensive neuronal volume loss, as observed in the IG, by acting as a prophylactic agent and buffering neural structural changes during chronical social isolation.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1457557"},"PeriodicalIF":2.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11886963/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143585488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frontiers in NeuroanatomyPub Date : 2025-02-12eCollection Date: 2025-01-01DOI: 10.3389/fnana.2025.1504065
Lidya K Yassin, Mohammed M Nakhal, Alreem Alderei, Afra Almehairbi, Ayishal B Mydeen, Amal Akour, Mohammad I K Hamad
{"title":"Exploring the microbiota-gut-brain axis: impact on brain structure and function.","authors":"Lidya K Yassin, Mohammed M Nakhal, Alreem Alderei, Afra Almehairbi, Ayishal B Mydeen, Amal Akour, Mohammad I K Hamad","doi":"10.3389/fnana.2025.1504065","DOIUrl":"10.3389/fnana.2025.1504065","url":null,"abstract":"<p><p>The microbiota-gut-brain axis (MGBA) plays a significant role in the maintenance of brain structure and function. The MGBA serves as a conduit between the CNS and the ENS, facilitating communication between the emotional and cognitive centers of the brain via diverse pathways. In the initial stages of this review, we will examine the way how MGBA affects neurogenesis, neuronal dendritic morphology, axonal myelination, microglia structure, brain blood barrier (BBB) structure and permeability, and synaptic structure. Furthermore, we will review the potential mechanistic pathways of neuroplasticity through MGBA influence. The short-chain fatty acids (SCFAs) play a pivotal role in the MGBA, where they can modify the BBB. We will therefore discuss how SCFAs can influence microglia, neuronal, and astrocyte function, as well as their role in brain disorders such as Alzheimer's disease (AD), and Parkinson's disease (PD). Subsequently, we will examine the technical strategies employed to study MGBA interactions, including using germ-free (GF) animals, probiotics, fecal microbiota transplantation (FMT), and antibiotics-induced dysbiosis. Finally, we will examine how particular bacterial strains can affect brain structure and function. By gaining a deeper understanding of the MGBA, it may be possible to facilitate research into microbial-based pharmacological interventions and therapeutic strategies for neurological diseases.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1504065"},"PeriodicalIF":2.1,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11860919/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143515340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frontiers in NeuroanatomyPub Date : 2025-02-12eCollection Date: 2025-01-01DOI: 10.3389/fnana.2025.1526962
Tao Qu
{"title":"The effects of amyloidosis and aging on glutamatergic and GABAergic synapses, and interneurons in the barrel cortex and non-neocortical brain regions.","authors":"Tao Qu","doi":"10.3389/fnana.2025.1526962","DOIUrl":"10.3389/fnana.2025.1526962","url":null,"abstract":"<p><p>Previous studies on changes in the distribution of GABAergic interneurons and excitation/inhibition (E/I) balance in Alzheimer's disease (AD) and aging were mainly conducted in the neocortex and hippocampus. However, the limbic system is the primary and crucial location for AD progression. Therefore, in this study, we utilized AD and aging mouse models to investigate the E/I balance and the distribution of parvalbumin (PV)- and somatostatin (SST)-expressing cells in S1BF (barrel field of primary somatosensory cortex, barrel cortex), CA1 hippocampal area and brain regions beyond the neocortex and hippocampus, including retrosplenial cortex (RSC, which is composed of RSG and RSA), piriform cortex (Pir), amygdala (BMA), and hypothalamus (DM). We discovered that amyloidosis may disrupt the alignment of excitatory pre- and postsynaptic quantities. Amyloidosis reduces the quantity of synapses and SST cells, but does not impact the counts of PV cells. By contrast, aging is linked to a decline in synapses, I/E ratios, SST and PV cells. Amyloidosis affects the S1BF and BMA, while aging may harm all studied regions, including the S1BF, RSC, hippocampus, Pir, BMA, and DM. Aging mostly affects synapses and I/E ratios in Pir, BMA, and DM, and PV and SST interneurons in the hippocampus.</p>","PeriodicalId":12572,"journal":{"name":"Frontiers in Neuroanatomy","volume":"19 ","pages":"1526962"},"PeriodicalIF":2.1,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11863279/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143515344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}