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1.
Stem Cell Res ; 79: 103470, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38896970

ABSTRACT

Autism spectrum disorder (ASD) is a complex developmental disorder characterized by challenges with social interactions and restricted/repetitive behaviors. Here, we recruited nine Qatari children of Arab ethnicity (males, aged 2-4 years), including six ASD subjects (n = 3 mild-to-moderate ASD and n = 3 severe ASD) and three control subjects. We generated induced pluripotent stem cell (iPSC) lines from PBMC samples of these subjects using non-integrating Sendai viral vectors. These iPSC lines were fully characterized and exhibited pluripotency characteristics, normal karyotypes, and trilineage differentiation potential. These iPSC lines provide valuable cell models for understanding ASD pathophysiology and developing new therapeutics for ASD.

2.
Stem Cell Rev Rep ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38916841

ABSTRACT

The pathogenesis of diabetes involves complex changes in the expression profiles of mRNA and non-coding RNAs within pancreatic islet cells. Recent progress in induced pluripotent stem cell (iPSC) technology have allowed the modeling of diabetes-associated genes. Our recent study using FOXA2-deficient human iPSC models has highlighted an essential role for FOXA2 in the development of human pancreas. Here, we aimed to provide further insights on the role of microRNAs (miRNAs) by studying the miRNA-mRNA regulatory networks in iPSC-derived islets lacking the FOXA2 gene. Consistent with our previous findings, the absence of FOXA2 significantly downregulated the expression of islet hormones, INS, and GCG, alongside other key developmental genes in pancreatic islets. Concordantly, RNA-Seq analysis showed significant downregulation of genes related to pancreatic development and upregulation of genes associated with nervous system development and lipid metabolic pathways. Furthermore, the absence of FOXA2 in iPSC-derived pancreatic islets resulted in significant alterations in miRNA expression, with 61 miRNAs upregulated and 99 downregulated. The upregulated miRNAs targeted crucial genes involved in diabetes and pancreatic islet cell development. In contrary, the absence of FOXA2 in islets showed a network of downregulated miRNAs targeting genes related to nervous system development and lipid metabolism. These findings highlight the impact of FOXA2 absence on pancreatic islet development and suggesting intricate miRNA-mRNA regulatory networks affecting pancreatic islet cell development.

3.
Cell Commun Signal ; 21(1): 229, 2023 09 05.
Article in English | MEDLINE | ID: mdl-37670346

ABSTRACT

BACKGROUND: Our recent studies have demonstrated the crucial involvement of FOXA2 in the development of human pancreas. Reduction of FOXA2 expression during the differentiation of induced pluripotent stem cells (iPSCs) into pancreatic islets has been found to reduce α-and ß-cell masses. However, the extent to which such changes are linked to alterations in the expression profile of long non-coding RNAs (lncRNAs) remains unraveled. METHODS: Here, we employed our recently established FOXA2-deficient iPSCs (FOXA2-/- iPSCs) to investigate changes in lncRNA profiles and their correlation with dysregulated mRNAs during the pancreatic progenitor (PP) and pancreatic islet stages. Furthermore, we constructed co-expression networks linking significantly downregulated lncRNAs with differentially expressed pancreatic mRNAs. RESULTS: Our results showed that 442 lncRNAs were downregulated, and 114 lncRNAs were upregulated in PPs lacking FOXA2 compared to controls. Similarly, 177 lncRNAs were downregulated, and 59 lncRNAs were upregulated in islet cells lacking FOXA2 compared to controls. At both stages, we observed a strong correlation between lncRNAs and several crucial pancreatic genes and TFs during pancreatic differentiation. Correlation analysis revealed 12 DE-lncRNAs that strongly correlated with key downregulated pancreatic genes in both PPs and islet cell stages. Selected DE-lncRNAs were validated using RT-qPCR. CONCLUSIONS: Our data indicate that the observed defects in pancreatic islet development due to the FOXA2 loss is associated with significant alterations in the expression profile of lncRNAs. Therefore, our findings provide novel insights into the role of lncRNA and mRNA networks in regulating pancreatic islet development, which warrants further investigations. Video Abstract.


Subject(s)
Induced Pluripotent Stem Cells , Insulin-Secreting Cells , RNA, Long Noncoding , Humans , Pancreas , Cell Differentiation , RNA, Messenger , Hepatocyte Nuclear Factor 3-beta
4.
Stem Cell Rev Rep ; 19(4): 1082-1097, 2023 05.
Article in English | MEDLINE | ID: mdl-36749553

ABSTRACT

Recently, we reported that forkhead box A2 (FOXA2) is required for the development of human pancreatic α- and ß-cells. However, whether miRNAs play a role in regulating pancreatic genes during pancreatic development in the absence of FOXA2 expression is largely unknown. Here, we aimed to capture the dysregulated miRNAs and to identify their pancreatic-specific gene targets in pancreatic progenitors (PPs) derived from wild-type induced pluripotent stem cells (WT-iPSCs) and from iPSCs lacking FOXA2 (FOXA2-/-iPSCs). To identify differentially expressed miRNAs (DEmiRs), and genes (DEGs), two different FOXA2-/-iPSC lines were differentiated into PPs. FOXA2-/- PPs showed a significant reduction in the expression of the main PP transcription factors (TFs) in comparison to WT-PPs. RNA sequencing analysis demonstrated significant reduction in the mRNA expression of genes involved in the development and function of exocrine and endocrine pancreas. Furthermore, miRNA profiling identified 107 downregulated and 111 upregulated DEmiRs in FOXA2-/- PPs compared to WT-PPs. Target prediction analysis between DEmiRs and DEGs identified 92 upregulated miRNAs, predicted to target 1498 downregulated genes in FOXA2-/- PPs. Several important pancreatic TFs essential for pancreatic development were targeted by multiple DEmiRs. Selected DEmiRs and DEGs were further validated using RT-qPCR. Our findings revealed that FOXA2 expression is crucial for pancreatic development through regulating the expression of pancreatic endocrine and exocrine genes targeted by a set of miRNAs at the pancreatic progenitor stage. These data provide novel insights of the effect of FOXA2 deficiency on miRNA-mRNA regulatory networks controlling pancreatic development and differentiation.


Subject(s)
Cell Differentiation , Gene Expression Regulation, Developmental , Hepatocyte Nuclear Factor 3-beta , Induced Pluripotent Stem Cells , Islets of Langerhans , MicroRNAs , Induced Pluripotent Stem Cells/cytology , Induced Pluripotent Stem Cells/metabolism , Hepatocyte Nuclear Factor 3-beta/genetics , Hepatocyte Nuclear Factor 3-beta/physiology , MicroRNAs/genetics , Humans , Islets of Langerhans/cytology , Islets of Langerhans/growth & development , Islets of Langerhans/metabolism , Cell Differentiation/genetics , Cell Line
5.
Stem Cell Res Ther ; 13(1): 428, 2022 08 20.
Article in English | MEDLINE | ID: mdl-35987697

ABSTRACT

BACKGROUND: The genetic factors associated with insulin resistance (IR) are not well understood. Clinical studies on first-degree relatives of type 2 diabetic (T2D) patients, which have the highest genetic predisposition to T2D, have given insights into the role of IR in T2D pathogenesis. Induced pluripotent stem cells (iPSCs) are excellent tools for disease modeling as they can retain the genetic imprint of the disease. Therefore, in this study, we aimed to investigate the genetic perturbations associated with insulin resistance (IR) in the offspring of T2D parents using patient-specific iPSCs. METHODS: We generated iPSCs from IR individuals (IR-iPSCs) that were offspring of T2D parents as well as from insulin-sensitive (IS-iPSCs) individuals. We then performed transcriptomics to identify key dysregulated gene networks in the IR-iPSCs in comparison to IS-iPSCs and functionally validated them. RESULTS: Transcriptomics on IR-iPSCs revealed dysregulated gene networks and biological processes indicating that they carry the genetic defects associated with IR that may lead to T2D. The IR-iPSCs had increased lactate secretion and a higher phosphorylation of AKT upon stimulation with insulin. IR-iPSCs have increased cellular oxidative stress indicated by a high production of reactive oxygen species and higher susceptibility to H2O2 -induced apoptosis. CONCLUSIONS: IR-iPSCs generated from offspring of diabetic patients confirm that oxidative stress and increased lactate secretion, associated with IR, are inherited in this population, and may place them at a high risk of T2D. Overall, our IR-iPSC model can be employed for T2D modeling and drug screening studies that target genetic perturbations associated with IR in individuals with a high risk for T2D.


Subject(s)
Diabetes Mellitus, Type 2 , Induced Pluripotent Stem Cells , Insulin Resistance , Diabetes Mellitus, Type 2/genetics , Humans , Hydrogen Peroxide , Induced Pluripotent Stem Cells/metabolism , Insulin/metabolism , Insulin Resistance/genetics , Lactates , Oxidative Stress
6.
Stem Cell Res ; 56: 102500, 2021 10.
Article in English | MEDLINE | ID: mdl-34438163

ABSTRACT

Autism spectrum disorder (ASD) is a childhood-onset neurodevelopmental disorder characterized by social interaction, behavior, and communication challenges. Here, we generated an induced pluripotent stem cell (iPSC) line, QBRIi013-A using a non-integrating Sendai virus from a 6-year-old female diagnosed with ASD and intellectual disability. The QBRIi013-A cell line was fully characterized and exhibited a pluripotency capacity and trilineage differentiation potential. Furthermore, it showed normal karyotype and genetic identity to the patient's PBMCs. Consequently, this iPSC line provides a valuable cell model in understanding the molecular mechanism underlying the complexities of ASD pathogenesis.


Subject(s)
Autism Spectrum Disorder , Induced Pluripotent Stem Cells , Intellectual Disability , Cell Line , Child , Female , Humans , Intellectual Disability/genetics , Sendai virus
7.
Int J Mol Sci ; 22(12)2021 Jun 18.
Article in English | MEDLINE | ID: mdl-34207213

ABSTRACT

Autism spectrum disorder (ASD) is a multifaced neurodevelopmental disorder that becomes apparent during early childhood development. The complexity of ASD makes clinically diagnosing the condition difficult. Consequently, by identifying the biomarkers associated with ASD severity and combining them with clinical diagnosis, one may better factionalize within the spectrum and devise more targeted therapeutic strategies. Currently, there are no reliable biomarkers that can be used for precise ASD diagnosis. Consequently, our pilot experimental cohort was subdivided into three groups: healthy controls, individuals those that express severe symptoms of ASD, and individuals that exhibit mild symptoms of ASD. Using next-generation sequencing, we were able to identify several circulating non-coding RNAs (cir-ncRNAs) in plasma. To the best of our knowledge, this study is the first to show that miRNAs, piRNAs, snoRNAs, Y-RNAs, tRNAs, and lncRNAs are stably expressed in plasma. Our data identify cir-ncRNAs that are specific to ASD. Furthermore, several of the identified cir-ncRNAs were explicitly associated with either the severe or mild groups. Hence, our findings suggest that cir-ncRNAs have the potential to be utilized as objective diagnostic biomarkers and clinical targets.


Subject(s)
Autism Spectrum Disorder/blood , Cell-Free Nucleic Acids/blood , RNA, Long Noncoding/blood , RNA, Small Untranslated/blood , Adolescent , Autism Spectrum Disorder/diagnosis , Biomarkers/blood , Child , Child, Preschool , Female , Humans , Male
8.
Stem Cell Res ; 54: 102433, 2021 07.
Article in English | MEDLINE | ID: mdl-34171785

ABSTRACT

Recessive mutations in the glucose transporter gene SLC2A2 (GLUT2) lead to permanent neonatal diabetes (PNDM) and Fanconi Bickel Syndrome (FBS). Here, we generated an induced pluripotent stem cell (iPSC) line, QBRIi012-A, from a 24-month-old boy with FBS and PNDM due to homozygous nonsense mutation in the SLC2A2 gene (c.901C > T). The QBRIi012-A was fully characterized using different approaches. The cell line showed normal karyotype and was able to differentiate into the three germ layers in vitro. This iPSC line provides a novel human cell model to understand the pathophysiology of FBS and diabetes associated with SLC2A2 defects.


Subject(s)
Diabetes Mellitus , Fanconi Syndrome , Induced Pluripotent Stem Cells , Child, Preschool , Glucose Transporter Type 2/genetics , Homozygote , Humans , Infant, Newborn , Male , Mutation
9.
World J Stem Cells ; 13(3): 221-235, 2021 Mar 26.
Article in English | MEDLINE | ID: mdl-33815671

ABSTRACT

Insulin resistance (IR) is associated with several metabolic disorders, including type 2 diabetes (T2D). The development of IR in insulin target tissues involves genetic and acquired factors. Persons at genetic risk for T2D tend to develop IR several years before glucose intolerance. Several rodent models for both IR and T2D are being used to study the disease pathogenesis; however, these models cannot recapitulate all the aspects of this complex disorder as seen in each individual. Human pluripotent stem cells (hPSCs) can overcome the hurdles faced with the classical mouse models for studying IR. Human induced pluripotent stem cells (hiPSCs) can be generated from the somatic cells of the patients without the need to destroy a human embryo. Therefore, patient-specific hiPSCs can generate cells genetically identical to IR individuals, which can help in distinguishing between genetic and acquired defects in insulin sensitivity. Combining the technologies of genome editing and hiPSCs may provide important information about the genetic factors underlying the development of different forms of IR. Further studies are required to fill the gaps in understanding the pathogenesis of IR and diabetes. In this review, we summarize the factors involved in the development of IR in the insulin-target tissues leading to diabetes. Also, we highlight the use of hPSCs to understand the mechanisms underlying the development of IR.

10.
Environ Sci Pollut Res Int ; 28(32): 44420-44431, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33846926

ABSTRACT

p-Nitrophenol (PNP) is the main end product of organophosphorus insecticides and a derivative of diesel exhaust particles. In addition to its unfavorable impact on reproductive functions in both genders, it also has various harmful physiological effects including lung cancer and allergic rhinitis. The identification of the cellular readout that functions in metabolic pathway perpetuation is still far from clear. This research aimed to study the impact of chronic PNP exposure on the health condition of the liver in Japanese quails. Quails were exposed to different concentrations of PNP as follows: 0.0 (control), 0.01mg (PNP/0.01), 0.1mg (PNP/0.1), and 1mg (PNP/1) per kg of body weight for 2.5 months through oral administration. Liver and plasma samples were collected at 1.5, 2, and 2.5 months post-treatment for biochemical, histopathology, and immunohistochemistry assessment. The plasma aspartate aminotransferase (AST) level was assessed enzymatically. The livers were collected for histopathology, glycogen accumulation, proliferating cell nuclear antigen (PCNA), and apoptosis assessment. Our results revealed an irregularity in body weight due to the long-term exposure of PNP with a significant reduction in liver weight. PNP treatment caused histopathological alterations in the hepatic tissues which increased in severity by the long-term exposure. The low dose led to mild degeneration with lymphocytic infiltration, while the moderate dose has a congestion effect with some necrosis; meanwhile severe hepatocyte degeneration and RBCs hemolysis were noticed due to high dose of PNP. Glycogen accumulation increased in hepatocytes by prolonged exposure to p-Nitrophenol with the highest intensity in the group treated by the high dose. Moderate and high doses of PNP resulted in a significant increase in apoptosis and hepatocytes' proliferation at the different time points after treatment. This increase is markedly notable and maximized at 2.5 months post-treatment. The damage occurred in a time-dependent manner. These changes reflected on the plasma hepatic enzyme AST that was clearly increased at 2.5 months of exposure. Therefore, it could be concluded that PNP has profound toxic effects on the liver in cellular level. Taking into consideration the time and dose factors, both have a synergistic effect on the accumulation of glycogen, apoptosis, and cellular proliferation, highlighting the power of cellular investigation which will potentially open the door for earlier medical intervention to counteract this toxicity. Collectively, PNP could have critical hurtful effects on the health of human beings, wild animals as well as livestock.


Subject(s)
Chemical and Drug Induced Liver Injury , Coturnix , Animals , Apoptosis , Female , Glycogen , Humans , Liver , Male , Nitrophenols
11.
Cell Death Dis ; 12(1): 103, 2021 01 20.
Article in English | MEDLINE | ID: mdl-33473118

ABSTRACT

FOXA2 has been identified as an essential factor for pancreas development and emerging evidence supports an association between FOXA2 and diabetes. Although the role of FOXA2 during pancreatic development is well-studied in animal models, its role during human islet cell development remains unclear. Here, we generated induced pluripotent stem cells (iPSCs) from a patient with FOXA2 haploinsufficiency (FOXA2+/- iPSCs) followed by beta-cell differentiation to understand the role of FOXA2 during pancreatic beta-cell development. Our results showed that FOXA2 haploinsufficiency resulted in aberrant expression of genes essential for the differentiation and proper functioning of beta cells. At pancreatic progenitor (PP2) and endocrine progenitor (EPs) stages, transcriptome analysis showed downregulation in genes associated with pancreatic development and diabetes and upregulation in genes associated with nervous system development and WNT signaling pathway. Knockout of FOXA2 in control iPSCs (FOXA2-/- iPSCs) led to severe phenotypes in EPs and beta-cell stages. The expression of NGN3 and its downstream targets at EPs as well as INSUILIN and GLUCAGON at the beta-cell stage, were almost absent in the cells derived from FOXA2-/- iPSCs. These findings indicate that FOXA2 is crucial for human pancreatic endocrine development and its defect may lead to diabetes based on FOXA2 dosage.


Subject(s)
Diabetes Mellitus/genetics , Hepatocyte Nuclear Factor 3-beta/deficiency , Insulin-Secreting Cells/metabolism , Pancreas/physiopathology , Animals , Disease Models, Animal , Humans , Mice , Transfection
12.
Stem Cell Res ; 48: 101991, 2020 10.
Article in English | MEDLINE | ID: mdl-32971462

ABSTRACT

Heterozygous and homozygous mutations in the glucokinase (GCK) gene leads to maturity-onset diabetes of the young type 2 (MODY2) and permanent neonatal diabetes (PNDM), respectively. Here, we report the generation of two induced pluripotent stem cell (iPSC) lines, QBRIi010-A and QBRIi011-A, from patients with MODY2 and PNDM due to mutations in the GCK gene (c.437 T > C). The generated iPSC lines displayed pluripotency characteristics, were able to differentiate into the three germ layers, and showed normal karyotypes. These iPSC lines will serve as valuable human cell models for understanding diabetes pathogenesis and developing new therpaies for diabetes.


Subject(s)
Diabetes Mellitus, Type 2 , Induced Pluripotent Stem Cells , Diabetes Mellitus, Type 2/genetics , Glucokinase/genetics , Humans , Infant, Newborn , Mutation/genetics
13.
Stem Cell Res ; 44: 101736, 2020 04.
Article in English | MEDLINE | ID: mdl-32146263

ABSTRACT

Fanconi Bickel Syndrome (FBS) is an autosomal recessive disease resulting from mutations in the SLC2A2 gene, encoding the GLUT2. FBS patients develop diabetes mellitus. Using non-integrating Sendai virus, we generated an induced pluripotent stem cell (iPSC) line, QBRIi007-A, carrying the c.613-7 T>G homozygous mutation in intron 5 of the SLC2A2 gene from a 19-year-old female with FBS and diabetes. The iPSC line was characterized for pluripotency, differentiation potential, genomic integrity, and genetic identity. This iPSC line provides a useful cell model to understand the role of GLUT2 in the disease development and to discover new drug candidates.


Subject(s)
Cell Line , Fanconi Syndrome , Induced Pluripotent Stem Cells , Adult , Female , Glucose Transporter Type 2 , Homozygote , Humans , Mutation , Young Adult
14.
Stem Cells Dev ; 29(7): 383-400, 2020 04 01.
Article in English | MEDLINE | ID: mdl-31996098

ABSTRACT

Psoriasis is characterized by hyperproliferation and defective differentiation of keratinocytes (KCs). Patients with psoriasis are at a high risk of developing diabetes and cardiovascular diseases. The debate on the genetic origin of psoriasis pathogenesis remains unresolved due to lack of suitable in vitro human models mimicking the disease phenotypes. In this study, we provide the first human induced pluripotent stem cell (iPSC) model for psoriasis carrying the genetic signature of the patients. iPSCs were generated from patients with psoriasis (PsO-iPSCs) and healthy donors (Ctr-iPSCs) and were efficiently differentiated into mature KCs. RNA sequencing of KCs derived from Ctr-iPSCs and PsO-iPSCs identified 361 commonly upregulated and 412 commonly downregulated genes. KCs derived from PsO-iPSCs showed dysregulated transcripts associated with psoriasis and KC differentiation, such as HLA-C, KLF4, chemokines, type I interferon-inducible genes, solute carrier family, IVL, DSG1, and HLA-DQA1, as well as transcripts associated with insulin resistance, such as IRS2, GDF15, GLUT10, and GLUT14. Our data suggest that the KC abnormalities are the main driver triggering psoriasis pathology and highlights the substantial contribution of genetic predisposition in the development of psoriasis and insulin resistance.


Subject(s)
Induced Pluripotent Stem Cells/physiology , Keratinocytes/physiology , Psoriasis/genetics , Adult , Cell Differentiation/genetics , Cells, Cultured , Female , Genetic Predisposition to Disease/genetics , Humans , Insulin Resistance/genetics , Kruppel-Like Factor 4 , Male , Middle Aged , Sequence Analysis, RNA/methods , Transcriptome/genetics
15.
Stem Cell Res ; 42: 101705, 2020 01.
Article in English | MEDLINE | ID: mdl-31991389

ABSTRACT

FOXA2 is a transcription factor, playing an important role during development. We established an induced pluripotent stem cell (iPSC) line, QBRIi009-A, using non-integrating Sendai virus from a 4-year-old boy, displaying a complex clinical phenotype. Molecular karyotyping and cytogenetics confirmed a de novo proximal 20p11.2 deletion with a reciprocal translocation between the short arm of chromosome 6 and 20. The deleted region (~969 kb) contains only one gene, FOXA2. The generated hiPSC line was fully characterized for its pluripotency and its genetic identity. This iPSC line provides a useful model to study FOXA2 role during human development and in disease pathogenesis.


Subject(s)
Hepatocyte Nuclear Factor 3-beta/genetics , Induced Pluripotent Stem Cells/metabolism , Animals , Cell Differentiation , Cell Line , Child, Preschool , Heterozygote , Humans , Male
16.
Int. j. morphol ; 37(2): 498-503, June 2019. graf
Article in English | LILACS | ID: biblio-1002250

ABSTRACT

A successive embryonic developmental study was conducted on the brain of twenty eight embryos and fetuses of one humped camel (Camelus Dromedarius), whose crown vertebral rump lengths (CVRL) ranged from 9 to 80 mm, collected from the El-Basateen (Cairo) and Belbees (ElSharqya) Slaughterhouse. The current investigation revealed that camel brain was found to consist of fore, mid and hind brains. The fore brain is divided into telencephalon and diencephalon while the rhombencephalon divided into metencephalon and myelencephalon. Flexures appeared between the vesicles are cervical flexure between the rhomencephalon and the spinal cord, cephalic flexure in the mesencephalon and pontine flexure between the metencephalon, and the myelencephalon of the hind brain (rhombencephalon). The cavity of the rhombencephalon is the fourth ventricle, while that of the diencephalon is the third ventricle, and those of the telencephalon are the lateral ventricles but that of mid brain is the cerebral aqueduct. myelencephalon becomes medulla oblongata and metencephalon developed to pons and cerebellum while mesencephalon gives rise to the cerebral crura and anterior and a posterior colliculus. Diencephalon gives the thalamus, hypothalamus, mamillary body, infundibulum and pineal body while telencephalon becomes the cerebral hemispheres and corpus striatum.


Se llevó a cabo un estudio del desarrollo embrionario cerebral de veintiocho embriones y fetos de camello jorobado (Camelus dromedarius). Las muestras fueron recolectadas en los mataderos de El-Basateen (El Cairo) y Belbees (ElSharqya). La investigación reveló que el cerebro de camello posee un cerebro anterior, medio y posterior. El cerebro anterior se divide en telencéfalo y diencéfalo, mientras que el rombencéfalo se divide en metencéfalo y mielencéfalo. Las flexiones encontradas entre las vesículas son la flexión cervical entre el rombencéfalo y la médula espinal; la flexión cefálica en el mesencéfalo; y la flexión pontina entre el metencéfalo y el mielencéfalo del cerebro posterior (rombencéfalo). La cavidad del rombencéfalo conforma el cuarto ventrículo, la del diencéfalo forma el tercer ventrículo, y las del telencéfalo a los ventrículos laterales. En el cerebro medio, la cavidad corresponde al acueducto cerebral. El mielencéfalo se convierte en médula oblonga y el metencéfalo deriva en puente y cerebelo, mientras que el mesencéfalo da lugar a la crura cerebral y a los colículos anterior y posterior. El diencéfalo origina el tálamo, el hipotálamo, el cuerpo mamilar, el infundíbulo y la hipófisis, mientras que del telencéfalo se originan los hemisferios cerebrales y el cuerpo estriado.


Subject(s)
Animals , Brain/embryology , Camelus , Brain/growth & development
17.
Stem Cell Res Ther ; 9(1): 83, 2018 04 03.
Article in English | MEDLINE | ID: mdl-29615106

ABSTRACT

BACKGROUND: The expression of a specific combination of transcription factors (TFs) in the multipotent progenitor cells (MPCs) is critical for determining pancreatic cell fate. NKX6.1 expression in PDX1+ MPCs is required for functional ß cell generation. We have recently demonstrated the generation of a novel population of human pluripotent stem cell (hPSC)-derived MPCs that exclusively express NKX6.1, independently of PDX1 (PDX1-/NKX6.1+). Therefore, the aim of this study was to characterize this novel population to elucidate its role in pancreatic development. METHODS: The hPSCs were exposed to two differentiation protocols to generate MPCs that were analyzed using different techniques. RESULTS: Based on the expression of PDX1 and NKX6.1, we generated three different populations of MPCs, two of them were NKX6.1+. One of these NKX6.1 populations coexpressed PDX1 (PDX1+/NKX6.1+) which is known to mature into functional ß cells, and an additional novel population did not express PDX1 (PDX1-/NKX6.1+) with an undefined role in pancreatic cell fate. This novel population was enriched using our recently established protocol, allowing their reorganization in three-dimensional (3D) structures. Since NKX6.1 induction in MPCs can direct them to endocrine and/or ductal cells in humans, we examined the coexpression of endocrine and ductal markers. We found that the expression of the pancreatic endocrine progenitor markers chromogranin A (CHGA) and neurogenin 3 (NGN3) was not detected in the NKX6.1+ 3D structures, while few structures were positive for NKX2.2, another endocrine progenitor marker, thereby shedding light on the origin of this novel population and its role in pancreatic endocrine development. Furthermore, SOX9 was highly expressed in the 3D structures, but cytokeratin 19, a main ductal marker, was not detected in these structures. CONCLUSIONS: These data support the existence of two independent NKX6.1+ MPC populations during human pancreatic development and the novel PDX1-/NKX6.1+ population may be involved in a unique trajectory to generate ß cells in humans.


Subject(s)
Cell Differentiation , Homeodomain Proteins/metabolism , Induced Pluripotent Stem Cells/cytology , Islets of Langerhans/cytology , Cells, Cultured , Homeobox Protein Nkx-2.2 , Homeodomain Proteins/genetics , Humans , Induced Pluripotent Stem Cells/metabolism , Islets of Langerhans/metabolism , Keratin-19/genetics , Keratin-19/metabolism , Nuclear Proteins , SOX9 Transcription Factor/genetics , SOX9 Transcription Factor/metabolism , Trans-Activators/genetics , Trans-Activators/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Zebrafish Proteins
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