A triple-transgenic (tyrosine hydroxylase/dopamine decarboxylase/GTP cyclohydrolase 1, TH/DDC/GCH1) bone marrow mesenchymal stem cell line (BMSCs) capable of stably synthesizing dopamine (DA) transmitters were established to provide experimental evidence for the clinical treatment of Parkinson's disease (PD) by using this cell line. The DA-BMSCs cell line that could stably synthesize and secrete DA transmitters was established by using the triple transgenic recombinant lentivirus. The triple transgenes (TH/DDC/GCH1) expression in DA-BMSCs was detected using reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescence. Moreover, the secretion of DA was tested by enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC). Chromosome G-banding analysis was used to detect the genetic stability of DA-BMSCs. Subsequently, the DA-BMSCs were stereotactically transplanted into the right medial forebrain bundle (MFB) of Parkinson's rat models to detect their survival and differentiation in the intracerebral microenvironment of PD rats. Apomorphine (APO)-induced rotation test was used to detect the improvement of motor dysfunction in PD rat models with cell transplantation. The TH, DDC and GCH1 were expressed stably and efficiently in the DA-BMSCs cell line, but not expressed in the normal rat BMSCs. The concentration of DA in the cell culture supernatant of the triple transgenic group (DA-BMSCs) and the LV-TH group was extremely significantly higher than that of the standard BMSCs control group (P < 0.000 1). After passage, DA-BMSCs stably produced DA. Karyotype G-banding analysis showed that the vast majority of DA-BMSCs maintained normal diploid karyotypes (94.5%). Moreover, after 4 weeks of transplantation into the brain of PD rats, DA-BMSCs significantly improved the movement disorder of PD rat models, survived in a large amount in the brain microenvironment, differentiated into TH-positive and GFAP-positive cells, and upregulated the DA level in the injured area of the brain. The triple-transgenic DA-BMSCs cell line that stably produced DA, survived in large numbers, and differentiated in the rat brain was successfully established, laying a foundation for the treatment of PD using engineered culture and transplantation of DA-BMSCs.
Rats ; Animals ; Dopamine ; Parkinson Disease/metabolism* ; Mesenchymal Stem Cells/metabolism* ; Cell Line ; Brain/metabolism* ; Cell Differentiation ; Mesenchymal Stem Cell Transplantation

Glioma is the most common and lethal intrinsic primary tumor of the brain. Its controversial origins may contribute to its heterogeneity, creating challenges and difficulties in the development of therapies. Among the components constituting tumors, glioma stem cells are highly plastic subpopulations that are thought to be the site of tumor initiation. Neural stem cells/progenitor cells and oligodendrocyte progenitor cells are possible lineage groups populating the bulk of the tumor, in which gene mutations related to cell-cycle or metabolic enzymes dramatically affect this transformation. Novel approaches have revealed the tumor-promoting properties of distinct tumor cell states, glial, neural, and immune cell populations in the tumor microenvironment. Communication between tumor cells and other normal cells manipulate tumor progression and influence sensitivity to therapy. Here, we discuss the heterogeneity and relevant functions of tumor cell state, microglia, monocyte-derived macrophages, and neurons in glioma, highlighting their bilateral effects on tumors. Finally, we describe potential therapeutic approaches and targets beyond standard treatments.
Humans ; Glioma/metabolism* ; Neuroglia/metabolism* ; Carcinogenesis/pathology* ; Neural Stem Cells/metabolism* ; Microglia/metabolism* ; Brain Neoplasms/metabolism* ; Tumor Microenvironment

Detailed characterizations of genomic alterations have not identified subtype-specific vulnerabilities in adult gliomas. Mapping gliomas into developmental programs may uncover new vulnerabilities that are not strictly related to genomic alterations. After identifying conserved gene modules co-expressed with EGFR or PDGFRA (EM or PM), we recently proposed an EM/PM classification scheme for adult gliomas in a histological subtype- and grade-independent manner. By using cohorts of bulk samples, paired primary and recurrent samples, multi-region samples from the same glioma, single-cell RNA-seq samples, and clinical samples, we here demonstrate the temporal and spatial stability of the EM and PM subtypes. The EM and PM subtypes, which progress in a subtype-specific mode, are robustly maintained in paired longitudinal samples. Elevated activities of cell proliferation, genomic instability and microenvironment, rather than subtype switching, mark recurrent gliomas. Within individual gliomas, the EM/PM subtype was preserved across regions and single cells. Malignant cells in the EM and PM gliomas were correlated to neural stem cell and oligodendrocyte progenitor cell compartment, respectively. Thus, while genetic makeup may change during progression and/or within different tumor areas, adult gliomas evolve within a neurodevelopmental framework of the EM and PM molecular subtypes. The dysregulated developmental pathways embedded in these molecular subtypes may contain subtype-specific vulnerabilities.
Humans ; Brain Neoplasms/pathology* ; Neoplasm Recurrence, Local/metabolism* ; Glioma/pathology* ; Neural Stem Cells/pathology* ; Oligodendrocyte Precursor Cells/pathology* ; Tumor Microenvironment

OBJECTIVES: To explore the potential biomarkers for the diagnosis of primary brain stem injury (PBSI) by using metabonomics method to observe the changes of metabolites in rats with PBSI caused death. METHODS: PBSI, non-brain stem brain injury and decapitation rat models were established, and metabolic maps of brain stem were obtained by LC-MS metabonomics method and annotated to the HMDB database. Partial least square-discriminant analysis (PLS-DA) and random forest methods were used to screen potential biomarkers associated with PBSI diagnosis. RESULTS: Eighty-six potential metabolic markers associated with PBSI were screened by PLS-DA. They were modeled and predicted by random forest algorithm with an accuracy rate of 83.3%. The 818 metabolic markers annotated to HMDB database were used for random forest modeling and prediction, and the accuracy rate was 88.9%. According to the importance in the identification of cause of death, the most important metabolic markers that were significantly up-regulated in PBSI group were HMDB0038126 (genipinic acid, GA), HMDB0013272 (N-lauroylglycine), HMDB0005199 [(R)-salsolinol] and HMDB0013645 (N,N-dimethylsphingosine). CONCLUSIONS GA, N-lauroylglycine, (R)-salsolinol and N,N-dimethylsphingosine are expected to be important metabolite indicators in the diagnosis of PBSI caused death, thus providing clues for forensic medicine practice.
Rats ; Animals ; Metabolomics/methods* ; Brain Injuries ; Biomarkers/metabolism* ; Brain Stem/metabolism*

Traumatic brain injury (TBI) contributes to the key causative elements of neurological deficits. However, no effective therapeutics have been developed yet. In our previous work, extracellular vesicles (EVs) secreted by stem cells from human exfoliated deciduous teeth (SHED) offered new insights as potential strategies for functional recovery of TBI. The current study aims to elucidate the mechanism of action, providing novel therapeutic targets for future clinical interventions. With the miRNA array performed and Real-time PCR validated, we revealed the crucial function of miR-330-5p transferred by SHED-derived EVs (SHED-EVs) in regulating microglia, the critical immune modulator in central nervous system. MiR-330-5p targeted Ehmt2 and mediated the transcription of CXCL14 to promote M2 microglia polarization and inhibit M1 polarization. Identified in our in vivo data, SHED-EVs and their effector miR-330-5p alleviated the secretion of inflammatory cytokines and resumed the motor functional recovery of TBI rats. In summary, by transferring miR-330-5p, SHED-EVs favored anti-inflammatory microglia polarization through Ehmt2 mediated CXCL14 transcription in treating traumatic brain injury.
Animals ; Brain Injuries, Traumatic/therapy* ; Chemokines, CXC/metabolism* ; Extracellular Vesicles/metabolism* ; Histocompatibility Antigens/metabolism* ; Histone-Lysine N-Methyltransferase/metabolism* ; Humans ; MicroRNAs/metabolism* ; Microglia/metabolism* ; Rats ; Stem Cells/metabolism*

Objective: To study the protective effects of metformin on noise-induced hearing loss (NIHL) and its differential protein omics expression profile. Methods: In January 2021, 39 male Wistar rats were randomly divided into control group, noise exposure group and metformin+noise exposure group, with 13 rats in each group. Rats in the noise exposure group and metformin+noise exposure group were continuously exposed to octave noise with sound pressure level of 120 dB (A) and center frequency of 8 kHz for 4 h. Rats in the metformin+noise exposure group were treated with 200 mg/kg/d metformin 3 d before noise exposure for a total of 7 d. Auditory brainstem response (ABR) was used to test the changes of hearing thresholds before noise exposure and 1, 4, 7 d after noise exposure in the right ear of rats in each group. Tandem mass tag (TMT) quantitative proteomics was used to identify and analyze the differentially expressed protein in the inner ear of rats in each group, and it was verified by immunofluorescence staining with frozen sections. Results: The click-ABR thresholds of right ear in the noise exposure group and metformin+noise exposure group were significantly higher than those in the control group 1, 4, 7 d after noise exposure (P<0.05) . The click-ABR threshold of right ear in the metformin+noise exposure group were significantly lower than that in the noise exposure group (P<0.05) . Compared with the noise exposure group, 1035 up-regulated proteins and 1145 down-regulated proteins were differentially expressed in the metformin+noise exposure group. GO enrichment analysis showed that the significantly differentially expressed proteins were mainly involved in binding, molecular function regulation, signal transduction, and other functions. Enrichment analysis of KEGG pathway revealed that the pathways for significant enrichment of differentially expressed proteins included phosphatidylinositol 3-kinase-protein kinase B (PI3K-Akt) signaling pathway, focal adhesion, diabetic cardiomyopathy, mitogen, and mitogen-activated protein kinase (MAPK) signaling pathway. Immunofluorescence experiments showed that compared with the noise exposure group, the fluorescence intensity of insulin-like growth factor 1 receptor (IGF1R) in the metformin+noise exposure group was increased, and the fluorescence intensity of eukaryotic translation initiation factor 4E binding protein 1 (eIF4EBP1) was decreased. Conclusion: Noise exposure can lead to an increase in rat hearing threshold, and metformin can improve noise-induced hearing threshold abnormalities through multiple pathways and biological processes.
Animals ; Auditory Threshold/physiology* ; Cochlea ; Ear, Inner ; Evoked Potentials, Auditory, Brain Stem/physiology* ; Hearing Loss, Noise-Induced/prevention & control* ; Male ; Metformin/pharmacology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Rats ; Rats, Wistar

Diffuse intrinsic pontine glioma (DIPG) is the main cause of brain tumor-related death among children. Until now, there is still a lack of effective therapy with prolonged overall survival for this disease. A typical strategy for preclinical cancer research is to find out the molecular differences between tumor tissue and para-tumor normal tissue, in order to identify potential therapeutic targets. Unfortunately, it is impossible to obtain normal tissue for DIPG because of the vital functions of the pons. Here we report the human fetal hindbrain-derived neural progenitor cells (pontine progenitor cells, PPCs) as normal control cells for DIPG. The PPCs not only harbored similar cell biological and molecular signatures as DIPG glioma stem cells, but also had the potential to be immortalized by the DIPG-specific mutation H3K27M in vitro. These findings provide researchers with a candidate normal control and a potential medicine carrier for preclinical research on DIPG.
Animals ; Brain Stem Neoplasms ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; Cellular Senescence ; Female ; Glioma ; genetics ; metabolism ; pathology ; Histones ; genetics ; Humans ; Mice, Inbred NOD ; Mice, SCID ; Neoplasm Transplantation ; Neoplastic Stem Cells ; drug effects ; metabolism ; pathology ; Neural Stem Cells ; drug effects ; metabolism ; pathology ; Pons ; embryology ; metabolism ; pathology ; Primary Cell Culture

N-methyladenosine (mA), catalyzed by the methyltransferase complex consisting of Mettl3 and Mettl14, is the most abundant RNA modification in mRNAs and participates in diverse biological processes. However, the roles and precise mechanisms of mA modification in regulating neuronal development and adult neurogenesis remain unclear. Here, we examined the function of Mettl3, the key component of the complex, in neuronal development and adult neurogenesis of mice. We found that the depletion of Mettl3 significantly reduced mA levels in adult neural stem cells (aNSCs) and inhibited the proliferation of aNSCs. Mettl3 depletion not only inhibited neuronal development and skewed the differentiation of aNSCs more toward glial lineage, but also affected the morphological maturation of newborn neurons in the adult brain. mA immunoprecipitation combined with deep sequencing (MeRIP-seq) revealed that mA was predominantly enriched in transcripts related to neurogenesis and neuronal development. Mechanistically, mA was present on the transcripts of histone methyltransferase Ezh2, and its reduction upon Mettl3 knockdown decreased both Ezh2 protein expression and consequent H3K27me3 levels. The defects of neurogenesis and neuronal development induced by Mettl3 depletion could be rescued by Ezh2 overexpression. Collectively, our results uncover a crosstalk between RNA and histone modifications and indicate that Mettl3-mediated mA modification plays an important role in regulating neurogenesis and neuronal development through modulating Ezh2.
Adenosine ; analogs & derivatives ; metabolism ; Adult Stem Cells ; cytology ; metabolism ; Animals ; Brain ; metabolism ; Cell Differentiation ; genetics ; Cell Proliferation ; Enhancer of Zeste Homolog 2 Protein ; metabolism ; Gene Expression Regulation ; Methyltransferases ; metabolism ; Mice, Inbred C57BL ; Neural Stem Cells ; cytology ; metabolism ; Neurogenesis ; genetics ; Neurons ; cytology ; metabolism ; RNA, Messenger ; genetics ; metabolism

Previous genetic fate-mapping studies have indicated that embryonic glial fibrillary acidic protein-positive (GFAP) cells are multifunctional progenitor/neural stem cells that can produce astrocytes as well as neurons and oligodendrocytes throughout the adult mouse central nervous system (CNS). However, emerging evidence from recent studies indicates that GFAP cells adopt different cell fates and generate different cell types in different regions. Moreover, the fate of GFAP cells in the young adult mouse CNS is not well understood. In the present study, hGFAP-Cre/R26R transgenic mice were used to investigate the lineage of embryonic GFAP cells in the young adult mouse CNS. At postnatal day 21, we found that GFAP cells mainly generated NeuN neurons in the cerebral cortex (both ventral and dorsal), hippocampus, and cerebellum. Strangely, these cells were negative for the Purkinje cell marker calbindin in the cerebellum and the neuronal marker NeuN in the thalamus. Thus, contrary to previous studies, our genetic fate-mapping revealed that the cell fate of embryonic GFAP cells at the young adult stage is significantly different from that at the adult stage.
Animals ; Astrocytes ; cytology ; metabolism ; Brain ; cytology ; growth & development ; metabolism ; Calbindins ; metabolism ; Glial Fibrillary Acidic Protein ; metabolism ; Mice ; Mice, Transgenic ; Nerve Tissue Proteins ; metabolism ; Neural Stem Cells ; cytology ; metabolism ; Neurons ; cytology ; metabolism ; Nuclear Proteins ; metabolism

The GABAergic neurons in the parafacial zone (PZ) play an important role in sleep-wake regulation and have been identified as part of a sleep-promoting center in the brainstem, but the long-range connections mediating this function remain poorly characterized. Here, we performed whole-brain mapping of both the inputs and outputs of the GABAergic neurons in the PZ of the mouse brain. We used the modified rabies virus EnvA-ΔG-DsRed combined with a Cre/loxP gene-expression strategy to map the direct monosynaptic inputs to the GABAergic neurons in the PZ, and found that they receive inputs mainly from the hypothalamic area, zona incerta, and parasubthalamic nucleus in the hypothalamus; the substantia nigra, pars reticulata and deep mesencephalic nucleus in the midbrain; and the intermediate reticular nucleus and medial vestibular nucleus (parvocellular part) in the pons and medulla. We also mapped the axonal projections of the PZ GABAergic neurons with adeno-associated virus, and defined the reciprocal connections of the PZ GABAergic neurons with their input and output nuclei. The newly-found inputs and outputs of the PZ were also listed compared with the literature. This cell-type-specific neuronal whole-brain mapping of the PZ GABAergic neurons may reveal the circuits underlying various functions such as sleep-wake regulation.
Animals ; Axons ; physiology ; Brain ; anatomy & histology ; Brain Mapping ; Brain Stem ; cytology ; GABAergic Neurons ; physiology ; Green Fluorescent Proteins ; genetics ; metabolism ; Mice ; Mice, Inbred C57BL ; Mice, Transgenic ; Neural Pathways ; physiology ; Peptide Elongation Factor 1 ; genetics ; metabolism ; Rabies virus ; genetics ; metabolism ; Transduction, Genetic ; Vesicular Inhibitory Amino Acid Transport Proteins ; genetics ; metabolism