Long-term expansion of human neural progenitor cells by epigenetic stimulation in vitro.
Zhang H, Zhao Y, Zhao C, Yu S, Duan D, Xu Q
Researchers successfully expanded human neural progenitor cells in a lab dish for eight months using a new monolayer culture technique. The study confirms these cells retain their identity and can become neurons or astrocytes, offering a potential source for future dopaminergic neuron research.
- Human neural progenitor cells expand exponentially for 240 days in monolayer culture.
- Cells maintain typical progenitor markers like nestin and express Nurr1.
- The method supports ex vivo gene transfer applications.
- Findings provide a potential cell source for dopaminergic neuron development studies.
Transactivation activity of Nur77 discriminates between Ca2+ and cAMP signals.
Klopotowska D, Matuszyk J, Rapak A, Gidzinska B, Cebrat M, Ziolo E, Strzadala L
This study shows that different cellular signals move the Nur77 protein to different locations within cells, with one signal keeping it in the cytoplasm and another moving it to the nucleus. This mechanism explains how cells distinguish between calcium and cAMP signals through protein location rather than just production levels. The findings are limited to basic cell biology and do not provide direct clinical insights for NR4A2-related syndromes.
- Nur77 protein moves to the nucleus with cAMP signals but stays in the cytoplasm with calcium signals.
- Both signals increase gene transcription, but only cAMP strongly activates Nur77's transactivation function.
- The study uses PC12 cells, a standard laboratory cell line for neuroendocrine research.
- Results suggest protein location, not just amount, determines how Nur77 responds to cellular signals.
Nurr1 co-localizes with EphB1 receptors in the developing ventral midbrain, and its expression is enhanced by the EphB1 ligand, ephrinB2.
Calò L, Spillantini M, Nicoletti F, Allen ND
This study shows that the EphB1 receptor and its ligand ephrinB2 regulate Nurr1 expression in developing mouse brains, suggesting a mechanism for dopaminergic neuron development. The findings are based entirely on embryonic mouse tissue and do not involve human patients or clinical treatments.
- EphB1 receptors and Nurr1 share similar expression patterns in early mouse embryonic midbrain.
- Applying ephrinB2 ligand increases Nurr1 mRNA and protein levels in mouse brain explants.
- High concentrations of ephrinB2 do not affect Nurr1 expression, indicating a dose-dependent effect.
- The study suggests EphB1 activation helps dopaminergic neurons develop in mice.
- No human data, clinical trials, or direct therapeutic implications are presented.
Induction patterns of transcription factors of the nur family (nurr1, nur77, and nor-1) by typical and atypical antipsychotics in the mouse brain: implication for their mechanism of action.
Maheux J, Ethier I, Rouillard C, Lévesque D
This study measures how different antipsychotic drugs change the levels of NR4A2 (Nurr1) and related genes in mouse brains. It finds that these drugs alter gene expression patterns in dopamine-related brain regions, which helps distinguish between typical and atypical medications.
- Researchers measured NR4A2 gene activity in mouse brains after giving antipsychotic drugs.
- Typical and atypical antipsychotics create distinct patterns of NR4A2 family gene expression.
- Drug effects on these genes correlate with dopamine receptor binding in the striatum.
- The study uses mice, not humans, to observe these molecular changes.
The NGFI-B family of transcription factors regulates expression of 3beta-hydroxysteroid dehydrogenase type 2 in the human ovary.
Havelock JC, Smith AL, Seely JB, Dooley CA, Rodgers RJ, Rainey WE, Carr BR
The NGFI-B protein, also known as NR4A1, helps control the production of progesterone in human ovarian cells by turning on the HSD3B2 gene, which is essential for hormone synthesis during ovulation.
- NGFI-B boosts HSD3B2 gene activity in ovarian cells
- This increases progesterone production during ovulation
- NR4A1 (NGFI-B) is more active than NURR1 or NOR-1 in human ovaries
- HSD3B2 activation depends on a specific NGFI-B binding site
- Hormones and signals like FSH trigger NGFI-B expression
Protein-protein interactions and transcriptional antagonism between the subfamily of NGFI-B/Nur77 orphan nuclear receptors and glucocorticoid receptor.
Martens C, Bilodeau S, Maira M, Gauthier Y, Drouin J
This study defines a molecular mechanism where glucocorticoids suppress gene expression by physically interacting with NR4A2 family proteins. It demonstrates that the glucocorticoid receptor directly binds to these orphan nuclear receptors to block their ability to activate transcription.
- Glucocorticoids repress genes targeted by NGFI-B, Nurr1, and NOR1.
- The glucocorticoid receptor physically interacts with all three NR4A2 family members.
- This interaction occurs via the DNA binding domains of the proteins.
- The mechanism resembles known transrepression pathways involving other transcription factors.
Dopaminergic neurons.
Chinta SJ, Andersen JK
This article explains that Nurr1 is a key transcription factor required for the development of dopaminergic neurons, which are the brain cells lost in Parkinson's disease. It highlights that while these neurons control movement and mood, their exact cause of death remains unknown.
- Nurr1 helps build midbrain dopamine neurons essential for movement and behavior.
- Loss of these neurons causes Parkinson's disease symptoms.
- The specific reason these neurons die is still unknown.
Nur77 family of nuclear hormone receptors.
Hsu HC, Zhou T, Mountz JD
This review describes the general biological functions of the Nur77 family of proteins, including Nurr1 (NR4A2), in cell growth, immune response, and inflammation. It highlights their dual roles in the nucleus and mitochondria but does not provide specific insights into NR4A2-related syndromes or potential treatments for affected children.
- Nurr1 is part of the Nur77 family of orphan nuclear receptors involved in transcription regulation.
- These proteins influence cell death, growth, and immune function in various tissues.
- The review focuses on general biochemical mechanisms rather than specific disease pathways.
- No clinical data or treatment strategies for NR4A2-related conditions are presented.
Chronic lithium decreases Nurr1 expression in the rat brain and impairs spatial discrimination.
Al Banchaabouchi M, Peña de Ortíz S, Menéndez R, Ren K, Maldonado-Vlaar CS
Chronic lithium treatment reduces Nurr1 levels in the rat hippocampus and impairs spatial learning. This study links lithium-induced cognitive deficits to decreased expression of the NR4A2 protein in specific brain regions.
- Lithium lowers Nurr1 expression in rat hippocampal regions like CA1.
- Rats given lithium show impaired spatial discrimination learning.
- Nurr1 levels rise back to normal after spatial training in treated rats.
- The study uses a rat model, not human participants or clinical data.
Nurr1 mutational screen in Parkinson's disease.
Tan EK, Chung H, Chandran VR, Tan C, Shen H, Yew K, Pavanni R, Puvan KA, Wong MC, Teoh ML, Yih Y, Zhao Y
No pathogenic mutations in the Nurr1 gene were found in Asian patients with familial or young-onset Parkinson's disease. The intron 7 +33 C-->T variant is common in Malay and Indian populations and is a harmless genetic variation, not a disease-causing mutation.
- No harmful Nurr1 mutations found in Asian Parkinson's patients
- Intron 7 +33 C-->T is a common variant in some ethnic groups
- This variant is not linked to Parkinson's disease
- It is a harmless genetic difference, not a disease cause
Presynaptic dopaminergic properties of differentiated mouse embryonic stem cells.
Nakano Y, Hirko AC, Smith AD, Oka M, Dawson R, Peris J, Terada N, Meyer EM
Differentiated mouse embryonic stem cells develop presynaptic dopaminergic functions, including dopamine uptake and release, when co-cultured with PA6 support cells. These cells express key dopaminergic genes such as Nurr1, TH, VMAT2, and DAT, demonstrating their potential for maintaining dopaminergic homeostasis in vitro.
- Mouse embryonic stem cells differentiate into dopaminergic neurons with functional presynaptic properties.
- Co-culture with PA6 cells yields approximately 30% tyrosine hydroxylase-positive cells.
- Cells exhibit sodium-dependent dopamine uptake and calcium-dependent dopamine release.
- Key dopaminergic genes including Nurr1, VMAT2, and DAT are expressed in these cultures.
NGFI-B (Nurr77/Nr4a1) orphan nuclear receptor in rat pinealocytes: circadian expression involves an adrenergic-cyclic AMP mechanism.
Humphries A, Weller J, Klein D, Baler R, Carter DA
This study maps the daily biological clock in rat pineal glands, showing that NGFI-B (Nur77/Nr4a1) protein levels rise at night through adrenergic signaling. It identifies Fra-2 as a regulatory partner for this specific receptor within the pineal gland.
- NGFI-B mRNA and protein peak at night in rat pinealocytes.
- Adrenergic receptors and cyclic AMP drive this nocturnal increase.
- Fra-2 protein regulates NGFI-B expression in the pineal gland.
- The study focuses on circadian rhythms, not NR4A2 or Nurr1.
The orphan nuclear receptors NURR1 and NGFI-B modulate aromatase gene expression in ovarian granulosa cells: a possible mechanism for repression of aromatase expression upon luteinizing hormone surge.
Wu Y, Ghosh S, Nishi Y, Yanase T, Nawata H, Hu Y
This study shows that NURR1 and NGFI-B proteins repress aromatase gene expression in ovarian cells, a mechanism relevant to reproductive biology rather than neurodevelopment. The findings do not provide direct insight into NR4A2-related syndrome or potential treatments for the child's condition. This research focuses on hormonal regulation in the ovary, which is unrelated to the dopaminergic pathways affected by NR4A2 mutations.
- NURR1 and NGFI-B repress aromatase gene expression in human ovarian granulosa cells.
- This repression occurs rapidly after luteinizing hormone surge during follicular development.
- The study uses a human granulosa-like tumor cell line (KGN) for analysis.
- DNA-binding domain of NURR1 is required for this transcriptional repression.
- Findings relate to ovarian steroidogenesis, not central nervous system function.
Nuclear orphan receptor Nurr1 directly transactivates the osteocalcin gene in osteoblasts.
Pirih FQ, Tang A, Ozkurt IC, Nervina JM, Tetradis S
This study shows that Nurr1 regulates bone formation by directly activating the osteocalcin gene in bone cells. It does not address brain development, dopamine signaling, or neurological symptoms relevant to NR4A2 syndrome.
- Nurr1 activates osteocalcin expression in bone-forming cells.
- The mechanism involves direct binding to specific DNA sites in the osteocalcin promoter.
- This research focuses entirely on skeletal biology, not neurology.
- No findings relate to dopaminergic neurons or human NR4A2 phenotypes.
Tyrosine hydroxylase-positive neurons intrinsic to the human striatum express the transcription factor Nurr1.
Cossette M, Parent A, Lévesque D
This study confirms that a small population of dopamine-producing neurons exists naturally within the human striatum and shares key molecular features with those in the substantia nigra. It establishes that these intrinsic striatal neurons consistently express both tyrosine hydroxylase and the transcription factor Nurr1.
- Dopamine neurons exist intrinsically within the human striatum, not just in the substantia nigra.
- These striatal neurons express Nurr1, the same transcription factor linked to NR4A2-related syndromes.
- The study uses post-mortem tissue from seven healthy individuals to reach these conclusions.
- Findings describe basic neuroanatomy without testing treatments or analyzing patient genetics.
Expression, purification, and initial structural characterization of rat orphan nuclear receptor NOR-1 LBD domain.
Razzera G, Vernal J, Portugal RV, Calgaro MR, Fernandez P, Zakin MM, Polikarpov I, Terenzi H
Researchers determined the physical structure of a specific part of the NOR-1 protein, which is closely related to NR4A2. This work provides structural data for laboratory analysis but does not offer clinical insights or treatment options for patients.
- The study characterizes the rat NOR-1 protein domain in a lab setting.
- NOR-1 belongs to the same family as NR4A2 (Nurr1).
- No ligands or binding sites are identified for this receptor.
- The findings apply only to basic molecular biology research.
Identification of a novel co-regulator interaction surface on the ligand binding domain of Nurr1 using NMR footprinting.
Codina A, Benoit G, Gooch JT, Neuhaus D, Perlmann T, Schwabe JW
Researchers identify a specific surface on the Nurr1 protein where co-repressor molecules bind to regulate gene activity. This discovery clarifies how Nurr1 functions at a molecular level by revealing an interaction site distinct from the classical ligand-binding groove.
- Nurr1 lacks a traditional ligand binding cavity filled with hydrophobic side chains.
- Co-repressors SMRT and NCoR bind to a novel hydrophobic patch on Nurr1.
- This interaction occurs in a groove between helices 11 and 12 of the protein.
- Mutations at this site abolish Nurr1 activation, confirming its functional importance.
Angiotensin II early regulated genes in H295R human adrenocortical cells.
Romero DG, Plonczynski M, Vergara GR, Gomez-Sanchez EP, Gomez-Sanchez CE
This study identifies 11 genes rapidly turned on by angiotensin II in human adrenal cells, including Nurr1 (NR4A2), which is involved in hormone production and cellular stress responses. These genes are activated before aldosterone is made and may help explain how angiotensin II drives adrenal hormone release.
- Angiotensin II quickly turns on 11 genes in adrenal cells
- NR4A2 (Nurr1) is among the genes activated
- Gene activation happens before aldosterone is produced
- Other hormones like potassium and endothelin also trigger these genes
- These genes may control how the adrenal gland responds to stress
Nurr1, an orphan nuclear receptor with essential functions in developing dopamine cells.
Perlmann T, Wallén-Mackenzie A
Nurr1 is a transcription factor essential for the development and survival of dopamine neurons in the brain. It functions by partnering with another protein, RXR, to activate genes required for dopamine production and neuronal health.
- Nurr1 drives dopamine neuron development in the embryonic midbrain.
- It partners with RXR to promote dopamine neuron survival.
- RXR ligands support neurons through this Nurr1-RXR partnership.
- Nurr1 maintains adult dopamine neurons and regulates other genes.
Differentiation and transcription factor gene therapy in experimental parkinson's disease: sonic hedgehog and Gli-1, but not Nurr-1, protect nigrostriatal cell bodies from 6-OHDA-induced neurodegeneration.
Hurtado-Lorenzo A, Millan E, Gonzalez-Nicolini V, Suwelack D, Castro MG, Lowenstein PR
This study shows that gene therapy using Sonic hedgehog or Gli-1 protects dopaminergic neurons in rats from toxin-induced death, while Nurr-1 (NR4A2) provides no protection. The findings suggest that NR4A2 is not a viable target for neuroprotective gene therapy in this context.
- Sonic hedgehog and Gli-1 protect dopaminergic cell bodies in rat brains from neurotoxin damage.
- NR4A2 (Nurr-1) gene therapy fails to protect neurons or axons in this Parkinson's model.
- The study uses a rat model, not human patients or clinical trials.
- Results indicate NR4A2 is ineffective for neuroprotection against 6-OHDA-induced degeneration.
Assessment of Nurr1 nucleotide variations in familial Parkinson's disease.
Levecque C, Destée A, Mouroux V, Amouyel P, Chartier-Harlin MC
This study found no evidence that mutations in the NR4A2 gene (Nurr1) contribute to familial Parkinson's disease in a French population, suggesting it is unlikely to be a major cause in this group.
- No NR4A2 mutations were found in French familial Parkinson's cases
- Previous links between NR4A2 and Parkinson's were not confirmed
- NR4A2 is unlikely to be a major cause of familial Parkinson's in this population
NR4A2 and schizophrenia: lack of association in a Portuguese/Brazilian study.
Ruano D, Macedo A, Dourado A, Soares MJ, Valente J, Coelho I, Santos V, Azevedo MH, Goodman A, Hutz MH, Gama C, Lobato MI, Belmonte-de-Abreu P, Palha JA
This study finds no evidence that the specific NR4A2 mutations previously linked to schizophrenia are present in a cohort of Portuguese and Brazilian patients with the condition. The results suggest these particular genetic variants do not contribute to schizophrenia in this population, though they do not rule out other potential roles for NR4A2 in brain development.
- Researchers screened 258 schizophrenia patients for known NR4A2 mutations.
- None of the previously reported schizophrenia-linked mutations were found.
- The study confirms these specific variants are not associated with schizophrenia in this group.
- Altered NR4A2 expression or other mutations may still play a role in the disease.
Efficient induction of dopaminergic neurons from embryonic stem cells for application to Parkinson's disease.
Kim DW
This study demonstrates that overexpressing the Nurr1 protein in embryonic stem cells significantly increases the efficiency of generating dopamine-producing neurons. The modified cells mature into functional dopaminergic neurons and show improved survival and phenotype after transplantation in animal models.
- Nurr1 overexpression boosts dopaminergic neuron generation from stem cells to nearly 90% efficiency.
- Genetically modified cells produce higher levels of dopamine than unmodified controls.
- Transplanted cells maintain dopaminergic characteristics in living animal models.
- The method combines genetic engineering with specific culture conditions for cell therapy.
Absence of NR4A2 exon 1 mutations in 108 families with autosomal dominant Parkinson disease.
Ibáñez P, Lohmann E, Pollak P, Durif F, Tranchant C, Agid Y, Dürr A, Brice A, French Parkinson's Disease Genetics Study Group
This study found no mutations in NR4A2 exon 1 among 108 families with autosomal dominant Parkinson’s disease, suggesting that NR4A2 exon 1 is not a common cause of inherited Parkinson’s in this group.
- NR4A2 exon 1 mutations were not found in 108 Parkinson’s families
- NR4A2 exon 1 is unlikely a major cause of inherited Parkinson’s
- Results help rule out a specific genetic cause in some cases
Novel splicing variant of the human orphan nuclear receptor Nurr1 gene.
Xu PY, Le WD
Researchers identified a new version of the Nurr1 gene that is present in body tissues like blood and liver but absent from the brain. This specific variant shows reduced activity in laboratory tests, suggesting it functions differently than the standard gene.
- The novel Nurr1 variant exists in non-neuronal human tissues such as lymphocytes and liver.
- The variant is not found in the adult brain or spinal cord.
- Laboratory assays show this variant has significantly lower transcriptional activity.
- The study does not link this variant to clinical symptoms or disease.
Evaluation of the role of Nurr1 in a large sample of familial Parkinson's disease.
Nichols WC, Uniacke SK, Pankratz N, Reed T, Simon DK, Halter C, Rudolph A, Shults CW, Conneally PM, Foroud T, Parkinson Study Group
Genetic changes in the Nurr1 gene are not linked to Parkinson's disease in this large group of families with the condition, suggesting Nurr1 is unlikely to be a major cause of familial Parkinson's in this population.
- No link found between Nurr1 gene changes and Parkinson's in 783 patients
- The previously reported Nurr1 mutations were not found in this study
- Nurr1 is not a significant risk factor for familial Parkinson's here
- Results suggest other genes likely play bigger roles in this group
Forskolin cooperating with growth factor on generation of dopaminergic neurons from human fetal mesencephalic neural progenitor cells.
Wang X, Li X, Wang K, Zhou H, Xue B, Li L, Wang X
Forskolin enhances the production of dopamine-producing neurons from human fetal stem cells when combined with FGF8. This combination increases the yield of mature dopaminergic neurons that express key markers like Nurr1 and tyrosine hydroxylase. The study suggests this method could improve cell therapies for neurodegenerative diseases.
- Forskolin boosts FGF8-driven generation of dopamine neurons from human fetal stem cells.
- Treated cells produce dopamine and express Nurr1, TH, and D2 receptor genes.
- The approach aims to improve cell replacement therapies for neurodegenerative conditions.
GDNF promotes neuronal differentiation and dopaminergic development of mouse mesencephalic neurospheres.
Roussa E, Krieglstein K
GDNF drives mouse stem cells to become dopaminergic neurons in a laboratory dish. This finding confirms basic biological mechanisms but provides no direct evidence for treating human patients with NR4A2-related syndromes.
- The study uses mouse embryonic stem cells, not human tissue or patients.
- GDNF increases the number of cells expressing early dopaminergic markers.
- No clinical outcomes, safety data, or human trials are reported.
- Results describe molecular pathways without immediate therapeutic application.
Over-expression of bHLH genes facilitate neural formation of mouse embryonic stem (ES) cells in vitro.
Kanda S, Tamada Y, Yoshidome A, Hayashi I, Nishiyama T
Forcing mouse stem cells to express specific neural genes rapidly creates early nerve cells and some dopamine-producing neurons in a petri dish. This study shows how basic genetic switches can drive initial brain cell formation but does not test treatments or analyze human patients with NR4A2 mutations. The findings describe general developmental biology rather than offering insights into the specific syndrome or potential therapies for your child.
- Mouse stem cells differentiate into nerve cells faster when forced to express NeuroD2 or Mash1 genes.
- The treated cells show markers of early neural development and some dopamine neuron characteristics.
- This is an in vitro study using mouse cells, with no human clinical data involved.
- The research focuses on general neural differentiation mechanisms rather than NR4A2-specific pathology.
Synaptotagmin IV overexpression inhibits depolarization-induced exocytosis in PC12 cells.
Machado HB, Liu W, Vician LJ, Herschman HR
Overexpressing synaptotagmin IV in PC12 cells reduces the release of neurotransmitter-like molecules in response to electrical stimulation, likely by interfering with calcium-triggered vesicle fusion. This effect depends on a specific amino acid change in synaptotagmin IV that prevents it from binding to cell membranes properly.
- Synaptotagmin IV blocks neurotransmitter release when overexpressed
- Its inhibitory effect relies on a unique serine in its calcium-binding site
- Changing serine to aspartate removes the inhibition
- Other immediate-early genes tested had no effect on exocytosis
- This suggests synaptotagmin IV may regulate synaptic signaling
Nur77 induction and activation are necessary for interleukin-1 stimulation of proopiomelanocortin in AtT-20 corticotrophs.
Kovalovsky D, Paez Pereda M, Labeur M, Renner U, Holsboer F, Stalla GK, Arzt E
This study shows that the protein Nur77 is required for immune signals to stimulate hormone production in pituitary cells. It does not provide information relevant to NR4A2-related syndromes or dopaminergic neuron function.
- The research focuses on pituitary corticotroph cells, not brain dopamine neurons.
- It examines Nur77 (NR4A1), a different gene from the child's NR4A2 mutation.
- The findings relate to immune response and ACTH secretion in pituitary tissue.
- No clinical data or treatment implications for NR4A2 syndrome are presented.
[The research advance of nuclear receptor Nurr1].
Lai YL, Xie ZP
This article is a general review of the Nurr1 nuclear receptor's biological functions and its role in various physiological processes. It does not provide specific clinical data, treatment options, or genetic insights relevant to NR4A2-related syndromes.
- The paper reviews general biology of the Nurr1 receptor.
- It covers broad physiological roles without disease-specific focus.
- No human clinical data or patient outcomes are included.
- It lacks specific guidance for NR4A2-related conditions.
Induction of orphan nuclear receptor Nur77 gene expression and its role in cadmium-induced apoptosis in lung.
Shin HJ, Lee BH, Yeo MG, Oh SH, Park JD, Park KK, Chung JH, Moon CK, Lee MO
Cadmium exposure triggers the expression of Nur77 family genes in lung cells, leading to apoptosis and lung toxicity. This process involves specific signaling pathways and is linked to cell death in both human lung cells and rat lungs.
- Cadmium induces Nur77 genes in lung cells
- Nur77 activation causes cell death in the lungs
- Blocking Nur77 reduces cadmium-induced apoptosis
- This pathway may explain cadmium lung damage
- Signaling pathways control Nur77 expression
Temporally induced Nurr1 can induce a non-neuronal dopaminergic cell type in embryonic stem cell differentiation.
Sonntag KC, Simantov R, Kim KS, Isacson O
Forcing Nurr1 expression in stem cell precursors creates non-neuronal cells that produce dopamine and express key dopaminergic markers. This process does not generate actual neurons but establishes a functional dopamine-producing cell type independent of neurogenesis.
- Nurr1 induction generates non-neuronal cells with dopamine transporters.
- These cells express midbrain dopaminergic markers like TH and AADC.
- Nurr1 maintains the phenotype by upregulating Ret and GDNF receptors.
- The induced cells function without becoming mature neurons.
Modulation of nurr1 gene expression in mesencephalic dopaminergic neurones.
Volpicelli F, Perrone-Capano C, Da Pozzo P, Colucci-D'Amato L, di Porzio U
This study shows that Nurr1 expression in rat brain cells increases with electrical activity and that Sonic hedgehog signaling promotes the growth of dopaminergic neurons. These findings describe basic developmental mechanisms in animal tissue cultures without testing any treatments or involving human patients.
- Nurr1 levels peak during early development in rat midbrain tissue.
- Electrical stimulation increases Nurr1 mRNA and protein in cultured cells.
- Sonic hedgehog signaling expands dopaminergic neuron populations in vitro.
- The research uses only rat embryonic brain cultures, not human subjects.
Regulation of the osteopontin gene by the orphan nuclear receptor NURR1 in osteoblasts.
Lammi J, Huppunen J, Aarnisalo P
This study shows that Nurr1 regulates bone formation by directly activating the osteopontin gene in bone cells. It demonstrates that Nurr1 works with vitamin D to promote this process but is inhibited by estrogen-related receptors.
- Nurr1 increases osteopontin mRNA expression in osteoblastic cell lines.
- Nurr1 directly binds to and activates the mouse osteopontin promoter.
- Nurr1 and vitamin D synergistically activate bone gene expression.
- Estrogen-related receptors repress Nurr1-mediated activation of the osteopontin promoter.
Rotenone induces non-specific central nervous system and systemic toxicity.
Lapointe N, St-Hilaire M, Martinoli MG, Blanchet J, Gould P, Rouillard C, Cicchetti F
Rotenone causes widespread toxicity in animals, affecting both the brain and body, and does not reliably produce Parkinson's-like symptoms or brain changes seen in human Parkinson's disease. The observed movement problems are likely due to general illness rather than specific damage to dopamine neurons.
- Rotenone causes systemic illness, not just brain damage
- Movement issues are linked to overall health, not Parkinson's-like brain changes
- No consistent loss of dopamine neurons in the brain
- Brain changes seen are likely due to general toxicity, not specific Parkinson's pathology
- Subcutaneous rotenone is not a good model for Parkinson's disease
Differential role of ERK in cAMP-induced Nurr1 expression in N2A and C6 cells.
Lee MK, Nikodem VM
This study shows that the ERK signaling pathway regulates Nurr1 expression differently depending on the cell type, acting as a necessary component in some cells but inhibiting it in others. The findings rely entirely on standard cancer and glioma cell lines without any animal models or clinical data.
- ERK pathway effects on Nurr1 vary between neuroblastoma and glioma cell lines.
- PKA activation drives Nurr1 expression in both cell types studied.
- MEK inhibition blocks Nurr1 induction in N2A cells but increases it in C6 cells.
- No human subjects, animal models, or therapeutic interventions are included.
- Results describe basic molecular mechanisms with no direct clinical application.
Defining an N-terminal activation domain of the orphan nuclear receptor Nurr1.
Nordzell M, Aarnisalo P, Benoit G, Castro DS, Perlmann T
Researchers identified a specific core region in the Nurr1 protein that activates gene expression and found that cellular signaling pathways can enhance this activity through phosphorylation. This work maps the molecular mechanics of how Nurr1 functions but does not test any treatments or analyze patient data. It provides basic biological context rather than clinical guidance for managing NR4A2-related syndrome.
- The study defines a short core activation region near the start of the Nurr1 protein.
- Cellular signaling pathways boost Nurr1 activity via specific phosphorylation sites.
- This is basic molecular biology with no human patient data or treatment testing.
- Findings do not directly inform clinical management or therapeutic options for NR4A2 syndrome.
Dopaminergic differentiation of human embryonic stem cells.
Zeng X, Cai J, Chen J, Luo Y, You ZB, Fotter E, Wang Y, Harvey B, Miura T, Backman C, Chen GJ, Rao MS, Freed WJ
Human embryonic stem cells differentiate into functional dopaminergic neurons when cultured with PA6 support cells, expressing key markers like Nurr1 and releasing dopamine. These generated neurons integrate into the brains of Parkinson's disease model rats, although survival rates after transplantation are low.
- PA6 coculture efficiently generates human dopaminergic neurons from embryonic stem cells.
- Differentiated cells express Nurr1 and other specific dopaminergic markers.
- Neurons release dopamine but not noradrenaline upon stimulation.
- Transplanted cells survive in rat brains but in very small numbers.