40 research outputs found
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Creation of a library of induced pluripotent stem cells from Parkinsonian patients.
Induced pluripotent stem cells (iPSCs) are becoming an important source of pre-clinical models for research focusing on neurodegeneration. They offer the possibility for better understanding of common and divergent pathogenic mechanisms of brain diseases. Moreover, iPSCs provide a unique opportunity to develop personalized therapeutic strategies, as well as explore early pathogenic mechanisms, since they rely on the use of patients' own cells that are otherwise accessible only post-mortem, when neuronal death-related cellular pathways and processes are advanced and adaptive. Neurodegenerative diseases are in majority of unknown cause, but mutations in specific genes can lead to familial forms of these diseases. For example, mutations in the superoxide dismutase 1 gene lead to the motor neuron disease amyotrophic lateral sclerosis (ALS), while mutations in the SNCA gene encoding for alpha-synuclein protein lead to familial Parkinson's disease (PD). The generations of libraries of familial human ALS iPSC lines have been described, and the iPSCs rapidly became useful models for studying cell autonomous and non-cell autonomous mechanisms of the disease. Here we report the generation of a comprehensive library of iPSC lines of familial PD and an associated synucleinopathy, multiple system atrophy (MSA). In addition, we provide examples of relevant neural cell types these iPSC can be differentiated into, and which could be used to further explore early disease mechanisms. These human cellular models will be a valuable resource for identifying common and divergent mechanisms leading to neurodegeneration in PD and MSA
Morphological Changes in Neural Progenitors Derived from Human Induced Pluripotent Stem Cells and Transplanted into the Striatum of a Parkinson's Disease Rat Model
Introduction. Development of cell therapy for Parkinson's disease (PD) requires protocols based on transplantation of neurons derived from human induced pluripotent stem cells (hiPSCs) into the damaged area of the brain.
Objective: to characterize neurons transplanted into a rat brain and evaluate neural transplantation efficacy using a PD animal model.
Materials and methods. Neurons derived from hiPSCs (IPSRG4S line) were transplanted into the striatum of rats after intranigral injection of 6-hydroxydopamine (6-OHDA). Immunostaining was performed to identify expression of glial and neuronal markers in the transplanted cells within 224 weeks posttransplant.
Results. 4 weeks posttransplant we observed increased expression of mature neuron markers, decreased expression of neural progenitor markers, and primary pro-inflammatory response of glial cells in the graft. Differentiation and maturation of neuronal cells in the graft lasted over 3 months. At 3 and 6 months we detected 2 graft zones: one mainly contained the transplanted neurons and the other human astrocytes. We detected human neurites in the corpus callosum and surrounding striatal tissue and large human tyrosine hydroxylase-expressing neurons in the graft.
Conclusion. With graft's morphological characteristics identified at different periods we can better understand pathophysiology and temporal patterns of new dopaminergic neurons integration and striatal reinnervation in a rat PD model in the long-term postoperative period
Unus pro omnibus, omnes pro uno: A novel, evidence-based, unifying theory for the pathogenesis of endometriosis
The theory of retrograde menstruation as aetiopathogenesis of endometriosis formulated by John Sampson in 1927 shows clear shortcomings: this does not explain why retrograde menstruation is a physiological process that affects 90% of women, while endometriosis occurs in only 10% of cases; it also does not explain the endometriotic foci distant from the pelvis, nor explains the cases of endometriosis in male patients. The immunological alterations of the peritoneal fluid explains the effects of disease, such as the inhibition of the physiological processes of cytolysis, but does not explain the cause. There is evidence to support the hypothesis that ectopic müllerian remnants of the endometrium, endocervix and endosalpinx are items from the genital ridge leaked during organogenesis. It is known that tissues derived from coelomatic epithelial and mesenchymal cells have the potential to metaplastically differentiate into epithelium and stroma. In addition, the phenotype of the ectopic endometrial cells is significantly different from those ectopic. There is scientific evidence that, during organogenesis, the genes of the Homeobox and Wingless family play a fundamental role in the differentiation of the ducts of Muller and development of the anatomical structure of the urogenital tract. We present here a hypothesis that deregulation of genes and the Wnt signaling pathway Wnt/β-catenin leads to aberrations and deregulation within the mesoderm, thus, may cause aberrant placement of stem cells. In addition, immune cells, adhesion molecules, extracellular matrix metalloproteinase and pro-inflammatory cytokines activate/alter peritoneal microenvironment, creating the conditions for differentiation, adhesion, proliferation and survival of ectopic endometrial cells
Screening ethnically diverse human embryonic stem cells identifies a chromosome 20 minimal amplicon conferring growth advantage
The International Stem Cell Initiative analyzed 125 human embryonic stem (ES) cell lines and 11 induced pluripotent stem (iPS) cell lines, from 38 laboratories worldwide, for genetic changes occurring during culture. Most lines were analyzed at an early and late passage. Single-nucleotide polymorphism (SNP) analysis revealed that they included representatives of most major ethnic groups. Most lines remained karyotypically normal, but there was a progressive tendency to acquire changes on prolonged culture, commonly affecting chromosomes 1, 12, 17 and 20. DNA methylation patterns changed haphazardly with no link to time in culture. Structural variants, determined from the SNP arrays, also appeared sporadically. No common variants related to culture were observed on chromosomes 1, 12 and 17, but a minimal amplicon in chromosome 20q11.21, including three genes expressed in human ES cells, ID1, BCL2L1 and HM13, occurred in >20% of the lines. Of these genes, BCL2L1 is a strong candidate for driving culture adaptation of ES cells
THE NEW APPROACHES TO THE STUDY OF THE CHROMOSOME LOOP ORGANISATION
The object of investigation: the DNA of the higher eucaryotes. The work is aimed at studying the specificity of the large-scale fragmentation of the higher eucaryotes genome. The methods of investigation: the pulse-electrophoresis, the DNA hybridization, the transfer on the nitrocellulose membranes, the cultivation of the eucaryotic cells, the autoradiography. The developed approaches of mapping the DNA loops allow to clear up the question of the correspondence of the DNA loops to the functional units of the genome. It has been shown, that the loop organisation of the DNA depends on the proliferative status of the cellsAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio
Patient-Specific iPSC-Based Models of Huntington’s Disease as a Tool to Study Store-Operated Calcium Entry Drug Targeting
Neurodegenerative pathologies are among the most serious and socially significant problems of modern medicine, along with cardiovascular and oncological diseases. Several attempts have been made to prevent neuronal death using novel drugs targeted to the cell calcium signaling machinery, but the lack of adequate models for screening markedly impairs the development of relevant drugs. A potential breakthrough in this field is offered by the models of hereditary neurodegenerative pathologies based on endogenous expression of mutant proteins in neurons differentiated from patient-specific induced pluripotent stem cells (iPSCs). Here, we study specific features of store-operated calcium entry (SOCE) using an iPSCs-based model of Huntington’s disease (HD) and analyze the pharmacological effects of a specific drug targeted to the calcium channels. We show that SOCE in gamma aminobutyric acid-ergic striatal medium spiny neurons (GABA MSNs) was mediated by currents through at least two different channel groups, ICRAC and ISOC. Both of these groups were upregulated in HD neurons compared with the wild-type neurons. Thapsigargin-induced intracellular calcium store depletion in GABA MSNs resulted in predominant activation of either ICRAC or ISOC. The potential anti-HD drug EVP4593, which was previously shown to have neuroprotective activity in different HD models, affected both ICRAC and ISOC
Methylation profile of induced pluripotent stem cells generated by integration and integration-free approaches
The genetic reprogramming technology allows generation of induced pluripotent stem cells (iPSCs) from somatic cells (Takahashi and Yamanaka, 2006) [1]. iPSCs have the ability to self-renew, and to differentiate into any type of somatic cells, and are considered as a promising tool for drug development, disease modeling, and regenerative medicine. The reprogramming factors (oct4, sox2, klf4, c-myc) can be delivered to the cell nucleus either by vectors integrating into the genome (lentiviruses, retroviruses) or by non-integrative methods (e.g., plasmids, Sendai virus, synthetic mRNAs and recombinant proteins). To evaluate the contribution of the reprogramming process isogenic system should be utilized (Shutova et al., 2016) [2]. Isogenic iPSC lines, obtained in different ways can serve the ideal system to investigate DNA methylation changes. The data presented in this article report methylation profiles for iPSC lines derived from fibroblasts of a healthy donor and PARK8-associated Parkinson's disease patient via integrating (lentiviral transfection) and non-integrating (Sendai virus infection) reprogramming using an Illumina 450K Methylation BeadChip platform. The data on DNA methylation of neurons differentiated from iPSC lines are also provided here. Keywords: Induced pluripotent stem cells, Illumina 450К Methylation BeadChip, DNA methylation, Sendai virus reprogramming, Lentiviral reprogrammin
Chromosome rearrangements in sublines of human embryonic stem cell lines hESM01 and hESM03
Due to possible proliferative effects of karyotypic reorganization of human embryonic stem cell (hESC) lines detailed genetic analysis are indicated prior to any application of hESCs. Molecular cytogenetic analysis of two different hESC sublines was performed and revealed aberrant chromosomes in both of them, i.e. in hESM01r18 (46,ХХ,-18,+mar) and hESM0309 (46,ХХ,del(4),dup(9)). This study shows that microdissection and multicolor fluorescence <em>in situ</em> hybridization (mFISH) can be used to detect the chromosomal changes precisely of the derivative chromosomes that are difficult to identify by conventional G-banded chromosome analysis. In the present study chromosome microdissection and reverse FISH were applied using multicolor fluorescence <em>in situ</em> hybridization (mFISH) for detailed characterization of the derivative chromosomes. The karyotypes of hESC lines were described as: 46,ХХ,r(18)(::p11.31→q21.2::q21.2→p11.31::) and 46,XX,del(4)(q25q31.1),dup(9)(q12q33), respectively. The potential role of the chromosomal regions involved in rearrangements for cell proliferation is discussed
Chromosome rearrangements in sublines of human embryonic stem cell lines hESM01 and hESM03
Due to possible proliferative effects of karyotypic reorganization of human embryonic stem cell (hESC) lines detailed genetic analysis are indicated prior to any application of hESCs. Molecular cytogenetic analysis of two different hESC sublines was performed and revealed aberrant chromosomes in both of them, i.e. in hESM01r18 (46,ХХ,-18,+mar) and hESM0309 (46,ХХ,del(4),dup(9)). This study shows that microdissection and multicolor fluorescence in situ hybridization (mFISH) can be used to detect the chromosomal changes precisely of the derivative chromosomes that are difficult to identify by conventional G-banded chromosome analysis. In the present study chromosome microdissection and reverse FISH were applied using multicolor fluorescence in situ hybridization (mFISH) for detailed characterization of the derivative chromosomes. The karyotypes of hESC lines were described as: 46,ХХ,r(18)(::p11.31→q21.2::q21.2→p11.31::) and 46,XX,del(4)(q25q31.1),dup(9)(q12q33), respectively. The potential role of the chromosomal regions involved in rearrangements for cell proliferation is discussed