-
Journal of Ethnopharmacology Sep 2024Citri Reticulata Pericarpium Viride (also known Qing-Pi or QP) is a plant in the Rutaceae family, QP is a traditional Qi-regulating medicine in Chinese medicine that is...
ETHNOPHARMACOLOGICAL RELEVANCE
Citri Reticulata Pericarpium Viride (also known Qing-Pi or QP) is a plant in the Rutaceae family, QP is a traditional Qi-regulating medicine in Chinese medicine that is compatible with other Chinese medicine components and has extensive clinical practice in treating anxiety and depression. Reports on the pharmacological effects of QP have demonstrated its neuroprotective effects and antioxidant capacities. Numerous pharmacological benefits of QP are attributed to its antioxidant abilities. Anxiety disorders are a broadly defined category of mental illnesses. Oxidative stress and an imbalance in the antioxidant defense system are typical pathological features of these disorders.
AIM OF THE STUDY
The aim of this study was to evaluate the effects of QP essential oil on anxiety using animal models and investigate the underlying neurobiological mechanisms.
MATERIALS AND METHODS
This study aimed to develop an animal model of anxiety using chronic restraint stress and investigate the effects of inhalation of Citri Reticulata Pericarpium Viride essential oil on anxiety-like behavior, olfactory function, and olfactory bulb neurogenesis in mice with anxiety.
RESULTS
The results showed that long-term chronic restraint stimulation caused a decrease in olfactory function, significant anxiety-like behavior, and a notable reduction in the number of neurons in the olfactory bulb. However, inhalation of Citri Reticulata Pericarpium Viride essential oil reversed these effects, improving the olfactory function, neuro-stimulating effect, alleviating anxiety-like behavior, and regulating theta (4-12Hz) oscillation in the hippocampus DG area. These effects were associated with changes in the expression levels of glutamate receptor NMDAR and NeuN in olfactory bulb.
CONCLUSIONS
The study revealed that mice with anxiety induced by chronic restraint stress exhibited significant olfactory dysfunction, providing strong evidence for the causal relationship between anxiety disorders and olfactory dysfunction. Moreover, QP essential oil has the potential to be developed as a therapeutic drug for anxiety disorders, in addition to its role as a complementary anxiolytic.
Topics: Animals; Oils, Volatile; Male; Anxiety; Mice; Olfactory Bulb; Anti-Anxiety Agents; Receptors, N-Methyl-D-Aspartate; Behavior, Animal; Glutamic Acid; Neurogenesis; Disease Models, Animal; Stress, Psychological
PubMed: 38735421
DOI: 10.1016/j.jep.2024.118332 -
Journal of Pharmaceutical Sciences May 2024The olfactory and trigeminal pathways are direct delivery pathways between the nose and brain. To determine the effect of direct delivery on drug distribution in the...
The olfactory and trigeminal pathways are direct delivery pathways between the nose and brain. To determine the effect of direct delivery on drug distribution in the brain, two model drugs with different physical properties, antipyrine (ANP), with high membrane permeability, and ranitidine (RNT), with low membrane permeability, were selected. For ANP, direct delivery from the nose to the brain was observed only in the olfactory bulb beside the nasal cavity, with a direct transport percentage (DTP) of approximately 45 %, whereas in the frontal and occipital brains, the contribution from the systemic circulation to the brain was observed as the primary route of brain distribution. No significant variations were observed in the pharmacokinetics of ANP in the left and right brain, whereas RNT was distributed in all brain regions with a DTP of > 95 %. The closer the brain region is to the nasal cavity, the higher the DTP. Furthermore, the left brain, the same nostril site (left nostril) of administration, had a larger level of drug delivery than the right brain. These findings imply that the influence of the administered nostril site differs based on the physicochemical properties and amount of the drug.
PubMed: 38734208
DOI: 10.1016/j.xphs.2024.05.003 -
International Journal of Molecular... May 2024The role of afferent target interactions in dendritic plasticity within the adult brain remains poorly understood. There is a paucity of data regarding the effects of...
The role of afferent target interactions in dendritic plasticity within the adult brain remains poorly understood. There is a paucity of data regarding the effects of deafferentation and subsequent dendritic recovery in adult brain structures. Moreover, although adult zebrafish demonstrate ongoing growth, investigations into the impact of growth on mitral cell (MC) dendritic arbor structure and complexity are lacking. Leveraging the regenerative capabilities of the zebrafish olfactory system, we conducted a comprehensive study to address these gaps. Employing an eight-week reversible deafferentation injury model followed by retrograde labeling, we observed substantial morphological alterations in MC dendrites. Our hypothesis posited that cessation of injury would facilitate recovery of MC dendritic arbor structure and complexity, potentially influenced by growth dynamics. Statistical analyses revealed significant changes in MC dendritic morphology following growth and recovery periods, indicating that MC total dendritic branch length retained significance after 8 weeks of deafferentation injury when normalized to individual fish physical characteristics. This suggests that regeneration of branch length could potentially function relatively independently of growth-related changes. These findings underscore the remarkable plasticity of adult dendritic arbor structures in a sophisticated model organism and highlight the efficacy of zebrafish as a vital implement for studying neuroregenerative processes.
Topics: Animals; Zebrafish; Olfactory Bulb; Dendrites; Neuronal Plasticity
PubMed: 38732248
DOI: 10.3390/ijms25095030 -
Animals : An Open Access Journal From... Apr 2024Nasopharyngeal myiasis in European roe deer is a pathological condition caused by the larval stages of , a fly from the Oestridae family. These larvae reside in the...
Nasopharyngeal myiasis in European roe deer is a pathological condition caused by the larval stages of , a fly from the Oestridae family. These larvae reside in the host's upper respiratory tract for months, inducing significant tissue damage and clinical symptoms. The lifecycle of is complex, involving three larval stages before maturation into adult flies, with each stage contributing to the progressive pathology observed in the host. Despite their prevalence, the histopathological effects of these larvae in the nasal and nasopharyngeal cavities have been understudied. Our study fills this knowledge gap by providing a detailed histopathological analysis of the affected tissues, using various staining techniques to reveal the extent and nature of the damage caused by these parasitic larvae. This histopathological examination reveals significant alterations within the nasopharyngeal mucosa and nasal cavity, including erythematous changes, mucosal metaplasia, fibrosis, and tissue necrosis. Parasitic cysts and eosinophilic infiltration further characterize the impact of the infestation, compromising not only the mucosal integrity but also potentially the olfactory function of the affected animals. This research is crucial for understanding the impact of myiasis on both the health and olfactory capabilities of roe deer populations and could have significant implications for wildlife management and conservation.
PubMed: 38731301
DOI: 10.3390/ani14091297 -
Bulletin of Experimental Biology and... Mar 2024This paper shows for the first time that co-transplantation of human olfactory ensheathing cells with neurotrophin-3 into spinal cord cysts is more effective for...
This paper shows for the first time that co-transplantation of human olfactory ensheathing cells with neurotrophin-3 into spinal cord cysts is more effective for activation of remyelination than transplantation of cells with brain-derived neurotrophic factor and a combination of these two factors. The studied neurotrophic factors do not affect proliferation and migration of ensheathing cells in vitro. It can be concluded that the maximum improvement of motor function in rats receiving ensheathing cells with neurotrophin-3 is largely determined by activation of remyelination.
Topics: Animals; Rats; Neurotrophin 3; Humans; Brain-Derived Neurotrophic Factor; Remyelination; Olfactory Bulb; Cell Proliferation; Spinal Cord; Myelin Sheath; Cells, Cultured; Cell Movement; Cysts; Female; Central Nervous System Cysts
PubMed: 38727956
DOI: 10.1007/s10517-024-06088-x -
Experimental Neurobiology Apr 2024The development of the olfactory system is influenced by sensory inputs, and it maintains neuronal generation and plasticity throughout the lifespan. The olfactory bulb...
The development of the olfactory system is influenced by sensory inputs, and it maintains neuronal generation and plasticity throughout the lifespan. The olfactory bulb contains a higher proportion of interneurons than other brain regions, particularly during the early postnatal period of neurogenesis. Although the relationship between sensory stimulation and olfactory bulb development during the postnatal period has been well studied, the molecular mechanisms have yet to be identified. In this study, we used western blotting and immunohistochemistry to analyze the expression of the transcription factor Npas4, a neuron-specific immediate-early gene that acts as a developmental regulator in many brain regions. We found that Npas4 is highly expressed in olfactory bulb interneurons during the early postnatal stages and gradually decreases toward the late postnatal stages. Npas4 expression was observed in all olfactory bulb layers, including the rostral migratory stream, where newborn neurons are generated and migrate to the olfactory bulb. Under sensory deprivation, the olfactory bulb size and the number of olfactory bulb interneurons were reduced. Furthermore, Npas4 expression and the expression of putative Npas4 downstream molecules were decreased. Collectively, these findings indicate that Npas4 expression induced by sensory input plays a role in the formation of neural circuits with excitatory mitral/tufted cells by regulating the survival of olfactory bulb interneurons during the early stages of postnatal development.
PubMed: 38724478
DOI: 10.5607/en23037 -
Proceedings of the National Academy of... May 2024During development, neural stem cells in the cerebral cortex, also known as radial glial cells (RGCs), generate excitatory neurons, followed by production of cortical...
During development, neural stem cells in the cerebral cortex, also known as radial glial cells (RGCs), generate excitatory neurons, followed by production of cortical macroglia and inhibitory neurons that migrate to the olfactory bulb (OB). Understanding the mechanisms for this lineage switch is fundamental for unraveling how proper numbers of diverse neuronal and glial cell types are controlled. We and others recently showed that Sonic Hedgehog (Shh) signaling promotes the cortical RGC lineage switch to generate cortical oligodendrocytes and OB interneurons. During this process, cortical RGCs generate intermediate progenitor cells that express critical gliogenesis genes , and . The increased expression and appearance of Egfr and Olig2 cortical progenitors are concurrent with the switch from excitatory neurogenesis to gliogenesis and OB interneuron neurogenesis in the cortex. While Shh signaling promotes expression in the developing spinal cord, the exact mechanism for this transcriptional regulation is not known. Furthermore, the transcriptional regulation of and has not been explored. Here, we show that in cortical progenitor cells, multiple regulatory programs, including Pax6 and Gli3, prevent precocious expression of , a gene essential for production of cortical oligodendrocytes and astrocytes. We identify multiple enhancers that control expression in cortical progenitors and show that the mechanisms for regulating expression are conserved between the mouse and human. Our study reveals evolutionarily conserved regulatory logic controlling the lineage switch of cortical neural stem cells.
Topics: Animals; Neurogenesis; Cerebral Cortex; Basic Helix-Loop-Helix Transcription Factors; ErbB Receptors; Mice; Oligodendrocyte Transcription Factor 2; Nerve Tissue Proteins; Hedgehog Proteins; PAX6 Transcription Factor; Neural Stem Cells; Homeodomain Proteins; Zinc Finger Protein Gli3; Eye Proteins; Repressor Proteins; Paired Box Transcription Factors; Neuroglia; Gene Expression Regulation, Developmental; Signal Transduction; Olfactory Bulb; Cell Lineage; Humans
PubMed: 38713624
DOI: 10.1073/pnas.2321711121 -
The Journal of Comparative Neurology May 2024Histamine H receptor (HR) in the central nervous system plays an important role in various functions, including learning and memory, aggression, feeding behaviors, and...
Histamine H receptor (HR) in the central nervous system plays an important role in various functions, including learning and memory, aggression, feeding behaviors, and wakefulness, as evidenced by studies utilizing HR knockout mice and pharmacological interventions. Although previous studies have reported the widespread distribution of HR in the brains of rats, guinea pigs, monkeys, and humans, the detailed distribution in the mouse brain remains unclear. This study provides a comprehensive description of the distribution of HR mRNA in the mouse brain using two recently developed techniques: RNAscope and in situ hybridization chain reaction, both of which offer enhanced sensitivity and resolution compared to traditional methodologies such as radioisotope labeling, which were used in previous studies. The HR mRNA expression was observed throughout the entire brain, including key regions implicated in sleep-wake regulatory functions, such as the pedunculopontine tegmental nucleus and dorsal raphe. Additionally, strong HR mRNA signals were identified in the paraventricular hypothalamus and ventromedial hypothalamus, which may explain the potential mechanisms underlying histamine-mediated feeding regulation. Notably, we identified strong HR mRNA expression in previously unreported cerebral regions, such as the dorsal endopiriform nucleus, bed nucleus of the accessory olfactory tract, and postsubiculum. These findings significantly contribute to our understanding of the multifaceted roles of HR in diverse brain functions.
Topics: Animals; Male; Mice; Brain; Brain Mapping; In Situ Hybridization; Mice, Inbred C57BL; Receptors, Histamine H1; RNA, Messenger
PubMed: 38712635
DOI: 10.1002/cne.25622 -
The European Journal of Neuroscience May 2024
PubMed: 38712542
DOI: 10.1111/ejn.16387 -
Neuroscience Jun 2024Parkinson's disease (PD) is a common and complex neurodegenerative disease. This disease is typically characterized by the formation of Lewy bodies in multiple brain...
Parkinson's disease (PD) is a common and complex neurodegenerative disease. This disease is typically characterized by the formation of Lewy bodies in multiple brain regions and dopaminergic neuronal loss in the substantia nigra pars compacta, resulting in non-motor symptoms (e.g., olfactory deficits) and motor dysfunction in the late stages. There is yet no effective cure for Parkinson's disease. Considering the neuroprotective effects of exosomes, we investigated whether intranasal administration of umbilical cord mesenchymal stem cell exosomes could improve behavioral functions in PD mice. First, exosomes were endocytosed by the cells in vitro and in vivo, indicating that exosomes can cross the blood-brain barrier. Second, we found that both motor and non-motor functions of the PD models were effectively improved during intranasal exosomes treatment. Finally, the activity of olfactory bulb neurons was improved and the loss of dopaminergic neurons in the substantia nigra pars compacta was reversed. Moreover, exosomes attenuated microglia and astrocyte activation, leading to a low level of inflammation in the brain. In conclusion, our study provided a new reference for the clinical application of exosomes in the treatment of PD.
Topics: Exosomes; Animals; Administration, Intranasal; Umbilical Cord; Mesenchymal Stem Cells; Male; Dopaminergic Neurons; Mice, Inbred C57BL; Olfactory Bulb; Parkinson Disease; Mice; Disease Models, Animal; Humans; Mesenchymal Stem Cell Transplantation; Microglia
PubMed: 38705349
DOI: 10.1016/j.neuroscience.2024.04.010