Dynamic expression of Dab2 in the mouse embryonic central nervous system

Endothelial FOXM1 and Dab2 promote diabetic wound healing

Diabetes mellitus can cause impaired and delayed wound healing, leading to lower extremity amputations; however, the mechanisms underlying the regulation of vascular endothelial growth factor-dependent (VEGF-dependent) angiogenesis remain unclear. In our study, the molecular underpinnings of endothelial dysfunction in diabetes are investigated, focusing on the roles of disabled-2 (Dab2) and Forkhead box M1 (FOXM1) in VEGF receptor 2 (VEGFR2) signaling and endothelial cell function. Bulk RNA-sequencing analysis identified significant downregulation of Dab2 in high-glucose-treated primary mouse skin endothelial cells. In diabetic mice with endothelial deficiency of Dab2, in vivo and in vitro angiogenesis and wound healing were reduced when compared with wild-type diabetic mice. Restoration of Dab2 expression by injected mRNA-containing, LyP-1-conjugated lipid nanoparticles rescued impaired angiogenesis and wound healing in diabetic mice. Furthermore, FOXM1 was downregulated in skin endothelial cells under high-glucose conditions as determined by RNA-sequencing analysis. FOXM1 was found to bind to the Dab2 promoter, regulating its expression and influencing VEGFR2 signaling. The FOXM1 inhibitor FDI-6 reduced Dab2 expression and phosphorylation of VEGFR2. Our study provides evidence of the crucial roles of Dab2 and FOXM1 in diabetic endothelial dysfunction and establishes targeted delivery as a promising treatment for diabetic vascular complications.

Genetic Markers of Spina Bifida in an Indian Cohort

Objective

To identify the genetic markers of spina bifida through a systematic survey of the exome in an Indian cohort.

Materials and Methods

Three consecutive patients (P1: 1 year, male; P2: 2.8 years, male; and P3: 10 years, female) with spina bifida (lumbosacral meningomyelocele) underwent whole-exome sequencing (libraries: SureSelect Human All Exon V8; sequencing: 2 * 150 bp paired-end run, 100×) with NovaSeq 6000. Data analysis was performed using SMART-One™ (secondary analysis) and SMARTer™ (tertiary analysis) for automated quality check, alignment (GRCh38/hg38), variant calling, annotation (ClinVar, OMIM, avsnp150, 1000 Genomes v5b, ExAC v0.3, gnomAD v4.0, and esp6500vi2all v0.0.25), v0.0.25), interpretation. The pathogenic and likely pathogenic (ClinVar/ InterVar), non-synonymous, exonic markers (read depth ≥ 5) were matched with the Familial Neural Tube Defects (Version 1.10) panel (FNTD panel).

Results

Pathogenic variants overlapping with the FNTD panel were MTRR, CC2D2A, and ZIC2 in P1 and P2, TGIF1 in P1 only, and none in P3. Novel pathogenic/likely pathogenic variants common to all three patients were PRUNE1, PKD1, PDZD2, and DAB2 in the homozygous state as well as in the heterozygous state, PLK1 and NLGN2. The possible role of such markers in etiopathogenesis was explored through a literatur search.

Conclusions

The genetic landscape of the spina bifida in an Indian cohort is diverse compared to that reported from other parts of the world. A comprehensive catalog of single-nucleotide variants in the etiopathogenesis of the spina bifida on a background of the Familial Neural Tube Defects Panel has been generated.

Interplay Between FoxM1 and Dab2 Promotes Endothelial Cell Responses in Diabetic Wound Healing

Diabetes mellitus can cause impaired and delayed wound healing, leading to lower extremity amputations; however, the mechanisms underlying the regulation of vascular endothelial growth factor (VEGF)-dependent angiogenesis remain uncertain and could reveal new therapeutic targets. In our study, the molecular underpinnings of endothelial dysfunction in diabetes were investigated, focusing on the roles of Disabled-2 (Dab2) and Forkhead Box M1 (FoxM1) in VEGF receptor 2 (VEGFR2) signaling and endothelial cell (EC) function. Bulk RNA-sequencing analysis identified significant downregulation of Dab2 in high concentrations glucose treated primary mouse skin ECs, simulating hyperglycemic conditions in diabetes mellitus. In diabetic mice with a genetic EC deficiency of Dab2 angiogenesis was reduced in vivo and in vitro when compared with wild-type mice. Restoration of Dab2 expression by injected mRNA-containing lipid nanoparticles rescued impaired angiogenesis and wound healing in diabetic mice. At the same time, FoxM1 was downregulated in skin ECs subjected to high glucose conditions as determined by RNA-sequencing analysis. FoxM1 was found to bind to the Dab2 promoter, regulating its expression and influencing VEGFR2 signaling. The FoxM1 inhibitor FDI-6 reduced Dab2 expression and phosphorylation of VEGFR2. These findings indicate that restoring Dab2 expression through targeted therapies can enhance angiogenesis and wound repair in diabetes. To explore this therapeutic potential, we tested LyP-1-conjugated lipid nanoparticles (LNPs) containing Dab2 or control mRNAs to target ECs and found the former significantly improved wound healing and angiogenesis in diabetic mice. This study provides evidence of the crucial roles of Dab2 and FoxM1 in diabetic endothelial dysfunction and establishes targeted delivery as a promising treatment for diabetic vascular complications.

The scaffold protein disabled 2 (DAB2) and its role in tumor development and progression

BACKGROUND

Disabled 2 (DAB2) is a multifunctional protein that has emerged as a critical component in the regulation of tumor growth. Its dysregulation is implicated in various types of cancer, underscoring its importance in understanding the molecular mechanisms underlying tumor development and progression. This review aims to unravel the intricate molecular mechanisms by which DAB2 exerts its tumor-suppressive functions within cancer signaling pathways.

METHODS AND RESULTS

We conducted a comprehensive review of the literature focusing on the structure, expression, physiological functions, and tumor-suppressive roles of DAB2. We provide an overview of the structure, expression, and physiological functions of DAB2. Evidence supporting DAB2's role as a tumor suppressor is explored, highlighting its ability to inhibit cell proliferation, induce apoptosis, and modulate key signaling pathways involved in tumor suppression. The interaction between DAB2 and key oncogenes is examined, elucidating the interplay between DAB2 and oncogenic signaling pathways. We discuss the molecular mechanisms underlying DAB2-mediated tumor suppression, including its involvement in DNA damage response and repair, regulation of cell cycle progression and senescence, and modulation of epithelial-mesenchymal transition (EMT). The review explores the regulatory networks involving DAB2, covering post-translational modifications, interactions with other tumor suppressors, and integration within complex signaling networks. We also highlight the prognostic significance of DAB2 and its role in pre-clinical studies of tumor suppression.

CONCLUSION

This review provides a comprehensive understanding of the molecular mechanisms by which DAB2 exerts its tumor-suppressive functions. It emphasizes the significance of DAB2 in cancer signaling pathways and its potential as a target for future therapeutic interventions.

MicroRNA‑93 knockdown inhibits acute myeloid leukemia cell growth via inactivating the PI3K/AKT pathway by upregulating DAB2

Acute myeloid leukemia (AML) is associated with a poor prognosis in elderly adults and currently lacks optimal treatment strategies. MicroRNAs (miRNAs or miRs) have increasingly been reported to be associated with AML progression; however, the mechanisms of action of miR-93 in AML with the involvement of disabled 2 (DAB2) are currently unknown. In the present study, miR-93 expression was assessed in patients with AML and in AML cell lines. The association between miR-93 expression and the pathological characteristics of patients with AML was analyzed. AML cells were then transfected to knockdown or overexpress miR-93 in order to elucidate its function in AML progression. The target gene of miR-93 was assessed using a dual-luciferase reporter gene assay. The expression levels of miR-93, DAB2 and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway-related proteins were measured and in vivo experiments were conducted to confirm the results. It was observed that miR-93 was highly expressed in patients with AML and in AML cells. The knockdown of miR-93 in HL-60 cells inhibited AML cell proliferation and resistance to apoptosis, while the overexpression of miR-93 in THP-1 cells led to contrasting results. Moreover, miR-93 targeted DAB2 to inactivate the PI3K/AKT pathway, and the overexpression of DAB2 reversed the effects of miR-93 on THP-1 cell growth. Tumor volume, tumor weight, and the positive expression of Ki67, survivin and p53 were increased in THP-1 cells overexpressing miR-93. On the whole, the present study demonstrates that miR-93 is highly expressed in AML cells, and that the suppression of miR-93 inhibits AML cell growth by targeting DAB2 and inhibiting the PI3K/AKT pathway.

The role of disabled-2 (Dab2) in diseases

Disabled-2 (Dab2/DOC-2) is a mitogen-responsive adaptor protein required for multiple cellular functions. It is involved in many signaling pathways and plays an integral role in vesicular uptake and trafficking, modulating immune function, protein-protein interactions, cellular homeostasis and differentiation, oncogenesis, and inflammatory processes in organ systems. It contains domains for binding to NPXY motif-containing and SH3 domain-containing adapter proteins, phosphoinositides, glycoprotein 100 (gp100, or megalin), integrins, clathrin, and myosin VI. However, the molecular mechanism(s) of Dab2's biological function still remain to be elucidated. In this review, we provide an extensive up-to-date understanding of the function of Dab2 and its regulation in cardiovascular diseases, immune disorders, tumorigenesis, and central nervous system disorders.

Disabled-2: a positive regulator of the early differentiation of myoblasts

Dab2 is an adaptor protein and a tumor suppressor. Our previous study has found that Dab2 was expressed in early differentiating skeletal muscles in mouse embryos. In this study, we determined the role of Dab2 in the skeletal muscle differentiation using C2C12 myoblasts in vitro and Xenopus laevis embryos in vivo. The expression of Dab2 was increased in C2C12 myoblasts during the formation of myotubes in vitro. Knockdown of Dab2 expression in C2C12 myoblasts resulted in a reduction of myotube formation, whereas the myotube formation was enhanced upon overexpression of Dab2. Re-expression of Dab2 in C2C12 myoblasts with downregulated expression of Dab2 restored their capacity to form myotubes. Microarray profiling and subsequent network analyses on the 155 differentially expressed genes after Dab2 knockdown showed that Mef2c was an important myogenic transcription factor regulated by Dab2 through the p38 MAPK pathway. It was also involved in other pathways that are associated with muscular development and functions. In Xenopus embryos developed in vivo, XDab2 was expressed in the myotome of somites where various myogenic markers were also expressed. Knockdown of XDab2 expression with antisense morpholinos downregulated the expression of myogenic markers in somites. In conclusion, this study is the first to provide solid evidence to show that Dab2 is a positive regulator of the early myoblast differentiation.

Single-cell profiling of the developing mouse brain and spinal cord with split-pool barcoding

To facilitate scalable profiling of single cells, we developed split-pool ligation-based transcriptome sequencing (SPLiT-seq), a single-cell RNA-seq (scRNA-seq) method that labels the cellular origin of RNA through combinatorial barcoding. SPLiT-seq is compatible with fixed cells or nuclei, allows efficient sample multiplexing, and requires no customized equipment. We used SPLiT-seq to analyze 156,049 single-nucleus transcriptomes from postnatal day 2 and 11 mouse brains and spinal cords. More than 100 cell types were identified, with gene expression patterns corresponding to cellular function, regional specificity, and stage of differentiation. Pseudotime analysis revealed transcriptional programs driving four developmental lineages, providing a snapshot of early postnatal development in the murine central nervous system. SPLiT-seq provides a path toward comprehensive single-cell transcriptomic analysis of other similarly complex multicellular systems.

Regeneration of Zebrafish CNS: Adult Neurogenesis

Regeneration in the animal kingdom is one of the most fascinating problems that have allowed scientists to address many issues of fundamental importance in basic biology. However, we came to know that the regenerative capability may vary across different species. Among vertebrates, fish and amphibians are capable of regenerating a variety of complex organs through epimorphosis. Zebrafish is an excellent animal model, which can repair several organs like damaged retina, severed spinal cord, injured brain and heart, and amputated fins. The focus of the present paper is on spinal cord regeneration in adult zebrafish. We intend to discuss our current understanding of the cellular and molecular mechanism(s) that allows formation of proliferating progenitors and controls neurogenesis, which involve changes in epigenetic and transcription programs. Unlike mammals, zebrafish retains radial glia, a nonneuronal cell type in their adult central nervous system. Injury induced proliferation involves radial glia which proliferate, transcribe embryonic genes, and can give rise to new neurons. Recent technological development of exquisite molecular tools in zebrafish, such as cell ablation, lineage analysis, and novel and substantial microarray, together with advancement in stem cell biology, allowed us to investigate how progenitor cells contribute to the generation of appropriate structures and various underlying mechanisms like reprogramming.

Transient activation of an adaptor protein, disabled-2, in rat spinal cord injury

We previously reported that disabled-2 (Dab-2), a cytosolic adaptor protein, was expressed in inflammatory and glial cells in the central nervous system (CNS) in experimental autoimmune encephalomyelitis and cerebral cryoinjury. Here, to determine the pattern of Dab-2 expression in a clip compression-induced rat spinal cord injury (SCI) model, the protein level and localization of Dab-2 in the spinal cord were investigated in rats with SCI using Western blotting and immunohistochemistry. Western blotting revealed that the expression of both the 75- and 100-kDa isoforms of Dab-2 peaked significantly in the spinal cord after clip compression injury 7 days post-injury compared to sham controls, and declined slightly thereafter. Immunohistochemistry revealed weak Dab-2 immunostaining in some neurons, glial cells, and ependymal cells in the spinal cords of the control animals, compared to staining in the macrophages and reactive astrocytes in lesions of the SCI animals. Overall, these findings suggest that both isoforms of Dab-2 are transiently upregulated in response to SCI and that the increased expression of Dab-2 is associated with the early activation of macrophages and astrogliosis in the course of CNS inflammation.

Effects of Prenatal Testosterone Exposure on Sexually Dimorphic Gene Expression in the Neonatal Mouse Cortex and Hippocampus

OBJECTIVE

Using gene expression microarrays and reverse transcription with quantitative polymerase chain reaction (RT-qPCR), we have recently identified several novel genes that are differentially expressed in the neonatal male versus female mouse cortex/hippocampus (Armoskus et al.). Since perinatal testosterone (T) secreted by the developing testes masculinizes cortical and hippocampal structures and the behaviors regulated by these brain regions, we hypothesized that sexually dimorphic expression of specific selected genes in these areas might be regulated by T during early development.

METHODS

To test our hypothesis, we treated timed pregnant female mice daily with vehicle or testosterone propionate (TP) starting on embryonic day 16 until the day of birth. The cortex/hippocampus was collected from vehicle- and TP-treated, male and female neonatal pups. Total RNA was extracted from these brain tissues, followed by RT-qPCR to measure relative mRNA levels of seven sex chromosome genes and three autosomal genes that have previously showed sex differences.

RESULTS

The effect of prenatal TP was confirmed as it stimulated Dhcr24 expression in the neonatal mouse cortex/hippocampus and increased the anogenital distance in females. We found a significant effect of sex, but not TP, on expression of three Y-linked (Ddx3y, Eif2s3y, and Kdm5d), four X-linked (Eif2s3x, Kdm6a, Mid1, and Xist), and one autosomal (Klk8) genes in the neonatal mouse cortex/hippocampus.

CONCLUSION

Although most of the selected genes are not directly regulated by prenatal T, their sexually dimorphic expression might play an important role in the control of sexually differentiated cognitive and social behaviors as well as in the etiology of sex-biased neurological disorders and mental illnesses.

Frequent loss expression of dab2 and promotor hypermethylation in human cancers: a meta-analysis and systematic review

Objective: Disabled-2 (Dab2) is an important endocytic adaptor which plays an inhibition role in cancer cell growth. The objective of this study was to systematically review expressions of Dab2 in human cancers.

Methods: Eligible studies about Dab2 in human cancers were retrieved from databases of PubMed, Embase, Web of Science. Odds Ratios (ORs) with 95% confidence intervals (CIs) were calculated using Review Manager 5.0 software and statistical analyses were performed by the SPSS 13.0 software.

Results: Fourteen case-control studies with a total of 689 human tumor tissues, 332 control tissues and 32 cancer cell lines were included in the meta-analysis study. The results indicated loss expressions of Dab2 were observed in 74.9% and 46.9% in human malignant cancer tissues and cancer cell lines, respectively. The ratio of Dab2 promotor hypermethylation is 34.54% in cancer tissues which Dab2 expression are lost, but none in the control tissues or cells by Methylation-specific PCR (MSP).

Conclusions: The expressions of Dab2 are frequently lost in human malignant cancer tissues, and promotor hypermethylation of Dab2 are common in human malignant cancer tissues, which is an important factor for the loss expression of Dab2 in human cancers tissues.

Identification of sexually dimorphic genes in the neonatal mouse cortex and hippocampus

The cerebral cortex and hippocampus are important for the control of cognitive functions and social behaviors, many of which are sexually dimorphic and tightly regulated by gonadal steroid hormones via activation of their respective nuclear receptors. As different levels of sex steroid hormones are present between the sexes during early development and their receptors act as transcription factors to regulate gene expression, we hypothesize that sexually dimorphic gene expression in the developing mouse cortex and hippocampus might result in sex differences in brain structures and neural circuits governing distinct behaviors between the sexes as adults. To test our hypothesis, we used gene expression microarrays to identify 90 candidate genes differentially expressed in the neonatal cortex/hippocampus between male and female mice, including 55 male-biased and 35 female-biased genes. Among these genes, sexually dimorphic expression of eight sex chromosome genes was confirmed by reverse transcription with quantitative PCR (RT-qPCR), including three located on the X chromosome (Xist, Eif2s3x, and Kdm6a), three on the Y chromosome (Ddx3y, Eif2s3y, and Kdm5d), and two in the pseudoautosomal region of the X and Y chromosomes (Erdr1 and Mid1). In addition, five autosomal genes (Cd151, Dab2, Klk8, Meg3, and Prkdc) were also validated for their sexually dimorphic expression in the neonatal mouse cortex/hippocampus. Gene Ontology annotation analysis suggests that many of these sexually dimorphic genes are involved in histone modifications, cell proliferation/death, androgen/estrogen signaling pathways, and synaptic organization, and these biological processes have been implicated in differential neural development, cognitive function, and neurological diseases between the sexes.

Genome wide expression profiling during spinal cord regeneration identifies comprehensive cellular responses in zebrafish

BACKGROUND

Among the vertebrates, teleost and urodele amphibians are capable of regenerating their central nervous system. We have used zebrafish as a model to study spinal cord injury and regeneration. Relatively little is known about the molecular mechanisms underlying spinal cord regeneration and information based on high density oligonucleotide microarray was not available. We have used a high density microarray to profile the temporal transcriptome dynamics during the entire phenomenon.

RESULTS

A total of 3842 genes expressed differentially with significant fold changes during spinal cord regeneration. Cluster analysis revealed event specific dynamic expression of genes related to inflammation, cell death, cell migration, cell proliferation, neurogenesis, neural patterning and axonal regrowth. Spatio-temporal analysis of stat3 expression suggested its possible function in controlling inflammation and cell proliferation. Genes involved in neurogenesis and their dorso-ventral patterning (sox2 and dbx2) are differentially expressed. Injury induced cell proliferation is controlled by many cell cycle regulators and some are commonly expressed in regenerating fin, heart and retina. Expression pattern of certain pathway genes are identified for the first time during regeneration of spinal cord. Several genes involved in PNS regeneration in mammals like stat3, socs3, atf3, mmp9 and sox11 are upregulated in zebrafish SCI thus creating PNS like environment after injury.

CONCLUSION

Our study provides a comprehensive genetic blue print of diverse cellular response(s) during regeneration of zebrafish spinal cord. The data highlights the importance of different event specific gene expression that could be better understood and manipulated further to induce successful regeneration in mammals.

Role of the subcommissural organ in the pathogenesis of congenital hydrocephalus in the HTx rat

The present investigation was designed to clarify the role of the subcommissural organ (SCO) in the pathogenesis of hydrocephalus occurring in the HTx rat. The brains of non-affected and hydrocephalic HTx rats from embryonic day 15 (E15) to postnatal day 10 (PN10) were processed for electron microscopy, lectin binding and immunocytochemistry by using a series of antibodies. Cerebrospinal fluid (CSF) samples of non-affected and hydrocephalic HTx rats were collected at PN1, PN7 and PN30 and analysed by one- and two-dimensional electrophoresis, immunoblotting and nanoLC-ESI-MS/MS. A distinct malformation of the SCO is present as early as E15. Since stenosis of the Sylvius aqueduct (SA) occurs at E18 and dilation of the lateral ventricles starts at E19, the malformation of the SCO clearly precedes the onset of hydrocephalus. In the affected rats, the cephalic and caudal thirds of the SCO showed high secretory activity with all methods used, whereas the middle third showed no signs of secretion. At E18, the middle non-secretory third of the SCO progressively fused with the ventral wall of SA, resulting in marked aqueduct stenosis and severe hydrocephalus. The abnormal development of the SCO resulted in the permanent absence of Reissner's fibre (RF) and led to changes in the protein composition of the CSF. Since the SCO is the source of a large mass of sialilated glycoproteins that form the RF and of those that remain CSF-soluble, we hypothesize that the absence of this large mass of negatively charged molecules from the SA domain results in SA stenosis and impairs the bulk flow of CSF through the aqueduct.

Analysis of the sacral neural crest cell contribution to the hindgut enteric nervous system in the mouse embryo

BACKGROUND & AIMS

The majority of the enteric nervous system is derived from the vagal neural crest, with a second contribution, which is restricted to the post-umbilical gut, originating from the sacral neural crest. In mammals, although sacral neural crest cells (NCCs) have been shown to enter the hindgut, information on their development and role remains scant. Our aim was to determine the migratory routes of sacral NCCs to the hindgut, their timing and site of entry into the gut, and their migratory behaviors and differentiation within the hindgut.

METHODS

We used in situ cell labeling, whole embryo culture, immunofluorescence, organotypic culture, and time-lapse live-cell imaging in mouse embryos.

RESULTS

Sacral NCCs emigrated from the neural tube at embryonic day 9.5, accumulated bilateral to the hindgut to form prospective pelvic ganglia at embryonic day 11.5, and from there entered the distal hindgut through its ventrolateral side at embryonic day 13.5. They then migrated along nerve fibers extending from the pelvic ganglia toward the proximal hindgut, intermingling with rostrocaudally migrating vagal NCCs to differentiate into neurons and glia. In organotypic culture, genetically labeled sacral and vagal NCCs displayed different capabilities of entering the hindgut, implying differences in their intrinsic migratory properties. Time-lapse live-cell imaging on explants ex vivo showed that sacral NCCs migrated along nerve fibers and exhibited different migratory behaviors from vagal NCCs.

CONCLUSIONS

Murine sacral NCCs are a distinct group of cells that migrate along defined pathways from neural tube to hindgut. They exhibit discrete migratory behaviors within the gut mesenchyme and contribute neurons and glial cells to the hindgut enteric nervous system.

Similarities and differences in structure, expression, and functions of VLDLR and ApoER2

Very Low Density Lipoprotein Receptor (VLDLR) and Apolipoprotein E Receptor 2 (ApoER2) are important receptors in the brain for mediating the signaling effects of the extracellular matrix protein Reelin, affecting neuronal function in development and in the adult brain. VLDLR and ApoER2 are members of the low density lipoprotein family, which also mediates the effects of numerous other extracellular ligands, including apolipoprotein E. Although VLDLR and ApoER2 are highly homologous, they differ in a number of ways, including structural differences, expression patterns, alternative splicing, and binding of extracellular and intracellular proteins. This review aims to summarize important aspects of VLDLR and ApoER2 that may account for interesting recent findings that highlight the unique functions of each receptor.

Cuprizone treatment induces demyelination and astrocytosis in the mouse hippocampus

Memory impairment is outstanding within the spectrum of cognitive deficits in multiple sclerosis (MS) patients. Demyelination has been reported in the hippocampus formation of MS patients. The degree of hippocampus lesions in MS strongly correlates with progression of cognitive dysfunction. Because no appropriate animal model for the study of hippocampus demyelination has been established, we used the cuprizone mouse model to investigated demyelination in young adult and aged mice. The myelin status was analyzed by classical histological staining, immunocytochemistry for proteolipoprotein, and electron microscopy. Oligodendrocyte, astroglial, and microglia markers were studied. Cuprizone intoxication induced an almost complete demyelination of distinct hippocampus subregions to a similar extent in young adult and aged male mice. Demyelination was pronounced in a subset of white and gray matter areas, i.e., the stratum lacunosum moleculare containing the perforant path, medial alveus, stratum pyramidale in the cornu ammonis 2/3 region, and hilus region. Besides demyelination, affected areas displayed hypertrophic and hyperplastic astrocytosis. No significant effect on microglia invasion was detected at any investigated time point (0, 3, 5, and 7 weeks). We conclude that cuprizone-induced demyelination provides an adequate animal model to investigate appropriate therapy strategies for the prevention of hippocampus demyelination.

Cuprizone treatment induces distinct demyelination, astrocytosis, and microglia cell invasion or proliferation in the mouse cerebellum

Demyelination of the cerebellum is a well-known phenomenon in human multiple sclerosis (MS). Concordantly, patients with MS frequently developed symptoms deriving from cerebellar lesions, i.e., dysmetria leading to hand dexterity impairment. Important advances in MS research have been made as a direct or indirect consequence of the establishment of adequate animal models. In this study, we used the cuprizone mouse model to investigate cerebellar demyelination in young adult male mice. The myelin status was analyzed by immunohistochemistry for proteolipoprotein and electron microscopy. The expression and presence of oligodendrocyte, astroglial, and microglia markers were supplementary studied. Cuprizone intoxication induced an almost complete demyelination of cerebellar nuclei. Cerebellar cortex regions were not (cortical gray matter) or only marginally (cortical white matter) affected. In addition, the affected areas displayed hypertrophic and hyperplastic astrocytosis accompanied by microglia or macrophage invasion. We conclude that cuprizone-induced demyelination pictures cerebellar deep gray matter involvement but not cerebellar cortex pathology as described for human MS. Behavioral changes after cuprizone described for this animal model may not only result from effects on commissural fiber tracts but also can arise from cerebellar demyelination.