Rotenone is a toxic isoflavone and an inhibitor of the mitochondrial respiratory chain. Rotenone is commonly used due to its piscicidal and pesticidal properties. The peripheral nervous system (PNS) lacks protective barriers and is exposed to many environmental substances due to its long-reaching structure.
View Article and Find Full Text PDFMicrofluidics have revolutionized cell culture by allowing for precise physical and chemical environmental control. Coupled with electrodes, microfluidic cell culture can be activated or have its changes sensed in real-time. We used our previously developed reliable and stable microfluidic device for cell growth and monitoring to design, fabricate, and characterize a whole-channel impedance-based sensor and used it to systematically assess the electrical and electrochemical influences of microfluidic channel boundaries coupled with varying electrode sizes, distances, coatings, and cell coverage.
View Article and Find Full Text PDFPeripheral autonomic nervous system (P-ANS) dysfunction is a critical non-motor phenotype of Parkinson's disease (PD). The majority of PD cases are sporadic and lack identified PD-associated genes involved. Epidemiological and animal model studies suggest an association with pesticides and other environmental toxins.
View Article and Find Full Text PDFExpansion mutations in polyalanine stretches are associated with a growing number of diseases sharing a high degree of genotypic and phenotypic commonality. These similarities prompted us to query the normal function of physiological polyalanine stretches and to investigate whether a common molecular mechanism is involved in these diseases. Here, we show that UBA6, an E1 ubiquitin-activating enzyme, recognizes a polyalanine stretch within its cognate E2 ubiquitin-conjugating enzyme USE1.
View Article and Find Full Text PDFAutism Spectrum Disorder (ASD) is characterized mainly by social and sensory-motor abnormal and repetitive behavior patterns. Over hundreds of genes and thousands of genetic variants were reported to be highly penetrant and causative of ASD. Many of these mutations cause comorbidities such as epilepsy and intellectual disabilities (ID).
View Article and Find Full Text PDFPleckstrin Homology And RUN Domain Containing M2 (PLEKHM2) [delAG] mutation causes dilated cardiomyopathy with left ventricular non-compaction (DCM-LVNC), resulting in a premature death of PLEKHM2[delAG] individuals due to heart failure. PLEKHM2 is a factor involved in autophagy, a master regulator of cellular homeostasis, decomposing pathogens, proteins and other cellular components. Autophagy is mainly carried out by the lysosome, containing degradation enzymes, and by the autophagosome, which engulfs substances marked for decomposition.
View Article and Find Full Text PDFMonocarboxylate transporter 8 (MCT8) deficiency is a rare genetic disease leading to a severe developmental delay due to a lack of thyroid hormones (THs) during critical stages of human brain development. Some MCT8-deficient patients are not as severely affected as others. Previously, we hypothesized that these patients' mutations do not affect the functionality but destabilize the MCT8 protein, leading to a diminished number of functional MCT8 molecules at the cell surface.
View Article and Find Full Text PDFAllan-Herndon-Dudley syndrome (AHDS) is a severe psychomotor disability disorder that also manifests characteristic abnormal thyroid hormone (TH) levels. AHDS is caused by inactivating mutations in monocarboxylate transporter 8 (MCT8), a specific TH plasma membrane transporter widely expressed in the central nervous system (CNS). mutations cause impaired transport of TH across brain barriers, leading to insufficient neural TH supply.
View Article and Find Full Text PDFPatients with Parkinson's disease present with signs and symptoms of dysregulation of the peripheral autonomic nervous system that can even precede motor deficits. This dysregulation might reflect early pathology and therefore could be targeted for the development of prodromal or diagnostic biomarkers. Only a few objective clinical tests assess disease progression and are used to evaluate the entire spectrum of autonomic dysregulation in patients with Parkinson's disease.
View Article and Find Full Text PDFFamilial Dysautonomia (FD) is an autosomal recessive congenital neuropathy affecting the development and function of the peripheral nervous system. FD causing gene is IKBKAP, encoding IkappaB kinase complex-associated protein also named elongator complex like protein 1 (IKAP/ELP1). The most common mutation (IVS20 + 6 T > C) causes an exon 20 skipping, leading to a truncated protein.
View Article and Find Full Text PDFActivity-dependent neuroprotective protein (ADNP) is essential for brain formation and function. As such, de novo mutations in ADNP lead to the autistic ADNP syndrome and somatic ADNP mutations may drive Alzheimer's disease (AD) tauopathy. Sirtuin 1 (SIRT1) is positively associated with aging, the major risk for AD.
View Article and Find Full Text PDFInactivating mutations in the thyroid hormone (TH) transporter monocarboxylate transporter 8 (MCT8) causes a rare and debilitating form of X-linked psychomotor disability known as Allan Herndon Dudley syndrome (AHDS). One of the most prominent pathophysiological symptoms of MCT8-deficiency is hypomyelination. Here, patient-derived induced pluripotent stem cells (iPSCs) were used to study the role of MCT8 and TH on the maturation of oligodendrocytes.
View Article and Find Full Text PDFStem Cell Res
March 2021
The GLUN2D subunit of the N-methylD-aspartate receptor (NMDAR) is encoded by the GRIN2D gene. Mutations in GRIN2D have been associated with neurodevelopmental and epileptic encephalopathies. Access to patient samples harboring mutations in GRIN2D can contribute to understanding the role of NMDAR in neuronal development and function.
View Article and Find Full Text PDFp450 oxidoreductase (POR) cytochromes are enzymes involved in the metabolism of steroids and sex hormones, in which POR acts as an electron donor. Inactivating mutations in the POR gene cause diverse deficiencies. Access to patient samples carrying these POR mutations can contribute to the understanding of metabolic and developmental processes.
View Article and Find Full Text PDFCongenital central hypoventilation syndrome (CCHS) is a rare life-threatening condition affecting the autonomic nervous system that usually presents shortly after birth as hypoventilation or central apnea during sleep. In the majority of cases, heterozygous polyalanine expansion mutations within the third exon of the paired-like homeobox 2B (PHOX2B) gene underlie CCHS. Here, we report the generation of two induced pluripotent stem cell (iPSC) lines from two identical twins with a heterozygous PHOX2B expansion mutation (+5 alanine residues).
View Article and Find Full Text PDFThe blood brain barrier (BBB) is formed by neurovascular units (NVUs) that shield the central nervous system (CNS) from a range of factors found in the blood that can disrupt delicate brain function. As such, the BBB is a major obstacle to the delivery of therapeutics to the CNS. Accumulating evidence suggests that the BBB plays a key role in the onset and progression of neurological diseases.
View Article and Find Full Text PDFThe blood-brain barrier (BBB) tightly regulates the entry of solutes from blood into the brain and is disrupted in several neurological diseases. Using Organ-Chip technology, we created an entirely human BBB-Chip with induced pluripotent stem cell (iPSC)-derived brain microvascular endothelial-like cells (iBMECs), astrocytes, and neurons. The iBMECs formed a tight monolayer that expressed markers specific to brain vasculature.
View Article and Find Full Text PDFInactivating mutations in the thyroid hormone (TH) transporter Monocarboxylate transporter 8 (MCT8) cause severe psychomotor retardation in children. Animal models do not reflect the biology of the human disease. Using patient-specific induced pluripotent stem cells (iPSCs), we generated MCT8-deficient neural cells that showed normal TH-dependent neuronal properties and maturation.
View Article and Find Full Text PDFBrain microvascular endothelial cells (BMECs) are an essential component of the blood-brain barrier (BBB) that shields the brain against toxins and immune cells. While BBB dysfunction exists in neurological disorders, including Huntington's disease (HD), it is not known if BMECs themselves are functionally compromised to promote BBB dysfunction. Further, the underlying mechanisms of BBB dysfunction remain elusive given limitations with mouse models and post-mortem tissue to identify primary deficits.
View Article and Find Full Text PDFThe blood-brain barrier (BBB) is critical in maintaining a physical and metabolic barrier between the blood and the brain. The BBB consists of brain microvascular endothelial cells (BMECs) that line the brain vasculature and combine with astrocytes, neurons and pericytes to form the neurovascular unit. We hypothesized that astrocytes and neurons generated from human-induced pluripotent stem cells (iPSCs) could induce BBB phenotypes in iPSC-derived BMECs, creating a robust multicellular human BBB model.
View Article and Find Full Text PDFThe mechanisms and treatment of psychomotor retardation, which includes motor and cognitive impairment, are indefinite. The Allan-Herndon-Dudley syndrome (AHDS) is an X-linked psychomotor retardation characterized by delayed development, severe intellectual disability, muscle hypotonia, and spastic paraplegia, in combination with disturbed thyroid hormone (TH) parameters. AHDS has been associated with mutations in the monocarboxylate transporter 8 (mct8/slc16a2) gene, which is a TH transporter.
View Article and Find Full Text PDFGNE Myopathy is a rare recessively inherited neuromuscular disorder caused by mutations in the GNE gene, which codes for the key enzyme in the metabolic pathway of sialic acid synthesis. The process by which GNE mutations lead to myopathy is not well understood. By in situ hybridization and gne promoter-driven fluorescent transgenic fish generation, we have characterized the spatiotemporal expression pattern of the zebrafish gne gene and have shown that it is highly conserved compared with the human ortholog.
View Article and Find Full Text PDFLight constitutes a primary signal whereby endogenous circadian clocks are synchronized ('entrained') with the day/night cycle. The molecular mechanisms underlying this vital process are known to require gene activation, yet are incompletely understood. Here, the light-induced transcriptome in the zebrafish central clock organ, the pineal gland, was characterized by messenger RNA (mRNA) sequencing (mRNA-seq) and microarray analyses, resulting in the identification of multiple light-induced mRNAs.
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