Glial controls systemic mitochondrial function, oxidative stress, and neuronal viability via copper ion homeostasis.

Cuprous copper [Cu(I)] is an essential cofactor for enzymes that support many fundamental cellular functions including mitochondrial respiration and suppression of oxidative stress. Neurons are particularly reliant on mitochondrial production of ATP, with many neurodegenerative diseases, including Parkinson's disease, associated with diminished mitochondrial function. The gene encodes a ribonuclease that targets pre-mRNA of replication-dependent histones, proteins recently found in yeast to reduce Cu(II) to Cu(I), and when mutated disrupt ATP production, elevates oxidative stress, and severely impacts cell growth.

Amphetamine Exposure during Embryogenesis Alters Expression and Function of Tyrosine Hydroxylase and the Vesicular Monoamine Transporter in Adult .

Amphetamines (Amph) are psychostimulants broadly used as physical and cognitive enhancers. However, the long-term effects of prenatal exposure to Amph have been poorly investigated. Here, we show that continuous exposure to Amph during early development induces long-lasting changes in histone methylation at the tyrosine hydroxylase (TH) homolog and the vesicular monoamine transporter (VMAT) homologue genes.

Effects of Heparan sulfate acetyl-CoA: Alpha-glucosaminide N-acetyltransferase (HGSNAT) inactivation on the structure and function of epithelial and immune cells of the testis and epididymis and sperm parameters in adult mice.

Heparan sulfate (HS), an abundant component of the apical cell surface and basement membrane, belongs to the glycosaminoglycan family of carbohydrates covalently linked to proteins called heparan sulfate proteoglycans. After endocytosis, HS is degraded in the lysosome by several enzymes, including heparan-alpha-glucosaminide N-acetyltransferase (HGSNAT), and in its absence causes Mucopolysaccharidosis III type C (Sanfilippo type C). Since endocytosis occurs in epithelial cells of the testis and epididymis, we examined the morphological effects of Hgsnat inactivation in these organs.

Long-Lasting Epigenetic Changes in the Dopamine Transporter in Adult Animals Exposed to Amphetamine during Embryogenesis: Investigating Behavioral Effects.

The dopamine transporter (DAT) is an integral member of the dopaminergic system and is responsible for the release and reuptake of dopamine from the synaptic space into the dopaminergic neurons. DAT is also the major target of amphetamine (Amph). The effects of Amph on DAT have been intensively studied; however, the mechanisms underlying the long-term effects caused by embryonal exposure to addictive doses of Amph remain largely unexplored.

Prolonged Amphetamine Exposures Increase the Endogenous Human Dopamine Receptors 2 at the Cellular Membrane in Cells Lacking the Dopamine Transporter.

The dopamine 2 receptors (D2R) are G-protein coupled receptors expressed both in pre- and post-synaptic terminals that play an important role in mediating the physiological and behavioral effects of amphetamine (Amph). Previous studies have indicated that the effects of Amph at the D2R mainly rely on the ability of Amph to robustly increase extracellular dopamine through the dopamine transporter (DAT). This implies that the effects of Amph on D2R require the neurotransmitter dopamine.

Caenorhabditis elegans as an in vivo Model to Assess Amphetamine Tolerance.

Amphetamine is a potent psychostimulant also used to treat attention deficit/hyperactivity disorder and narcolepsy. In vivo and in vitro data have demonstrated that amphetamine increases the amount of extra synaptic dopamine by both inhibiting reuptake and promoting efflux of dopamine through the dopamine transporter. Previous studies have shown that chronic use of amphetamine causes tolerance to the drug.

Prolonged Amphetamine Treatments Cause Long-Term Decrease of Dopamine Uptake in Cultured Cells.

Amphetamine (AMPH) is a systemic stimulant used to treat a variety of diseases including Attention Deficit Hyperactive Disorder, narcolepsy and obesity. Previous data showed that by binding to catecholamine transporters, AMPH prevents the reuptake of the neurotransmitters dopamine (DA) and norepinephrine (NE). Because AMPH, either used therapeutically at final concentrations of 1-10 µM or abused as recreational drug (50-200 µM), is taken over long periods of time, we investigated the prolonged effects of this drug on the uptake of DA.

Swimming Induced Paralysis to Assess Dopamine Signaling in Caenorhabditis elegans.

The swimming assay described in this protocol is a valid tool to identify proteins regulating the dopaminergic synapses. Similar to mammals, dopamine (DA) controls several functions in C. elegans including learning and motor activity.

Hypoxia-ischemia alters distribution of lysosomal proteins in rat cortex and hippocampus.

Neuronal excitotoxicity induced by glutamatergic receptor overstimulation contributes to brain damage. Recent studies have shown that lysosomal membrane permeabilization (LMP) is involved in ischemia-associated neuronal death. In this study we evaluated the effect of neonatal hypoxia-ischemia (HI), as a model of excitotoxicity, on the lysosomal integrity throughout the distribution of the lysosomal proteins cathepsin D and prosaposin.

Silencing of in the Dopaminergic Neurons Decreases the Activity of the Dopamine Transporter and Prevents Amphetamine-Induced Behaviors in .

The dopamine transporter (DAT) is a cell membrane protein whose main function is to reuptake the dopamine (DA) released in the synaptic cleft back into the dopaminergic neurons. Previous studies suggested that the activity of DAT is regulated by allosteric proteins such as Syntaxin-1A and is altered by drugs of abuse such as amphetamine (Amph). Because expresses both DAT (DAT-1) and Syntaxin-1A (UNC-64), we used this model system to investigate the functional and behavioral effects caused by lack of expression of in cultured dopaminergic neurons and in living animals.

Targeting exogenous β-Defensin to the endolysosomal compartment via a vehicle guided system.

A number of pathogens for which there are no effective treatments infect the cells via endocytosis. Once in the endosomes, the pathogens complete their life cycle by overriding normal lysosomal functions. Recently, our laboratory identified the lysosomal targeting signal of prosaposin, which is recognized by the sorting receptor "sortilin".

Glycosidases Interact Selectively With Mannose-6-Phosphate Receptors of Bull Spermatozoa.

Glycosidases may play a role in sperm maturation during epididymal transit. In this work, we describe the interaction of these enzymes with bull spermatozoa. We found that β-galactosidase associated to spermatozoa can be released under low ionic strength conditions, whereas the interaction of N-acetyl-β-D-glucosaminidase and β-glucuronidase with spermatozoa appeared to be stronger.

Glial Expression of the Caenorhabditis elegans Gene swip-10 Supports Glutamate Dependent Control of Extrasynaptic Dopamine Signaling.

Glial cells play a critical role in shaping neuronal development, structure, and function. In a screen for Caenorhabditis elegans mutants that display dopamine (DA)-dependent, Swimming-Induced Paralysis (Swip), we identified a novel gene, swip-10, the expression of which in glia is required to support normal swimming behavior. swip-10 mutants display reduced locomotion rates on plates, consistent with our findings of elevated rates of presynaptic DA vesicle fusion using fluorescence recovery after photobleaching.

Changes in lysosomal enzymes and mannose-6-phosphate receptors related to sexual maturation in bull epididymis.

One of the most striking features of the mammalian epididymis is the secretion of lysosomal enzymes (LE). These LE may play a role in sperm maturation. In the present study we investigated the activity and distribution of four LE (?-galactosidase (?-Gal), N-acetyl-?-D-glucosaminidase (?-NAG), ?-mannosidase (?-Man) and ?-glucuronidase (?-Glu)) in bull epididymis at two different ages (6 months and 4 years) to determine whether these enzymes vary with sexual maturity.

The Epigenetic Mechanisms of Amphetamine.

Amphetamine (AMPH) is a psychostimulant and the most prescribed drug to treat attention deficit hyperactive disorder (ADHD). Although therapeutically used doses are generally well tolerated, numerous side effects are still known to occur, such as jitteriness, loss of appetite and psychosis. Moreover, AMPH is liable to be abused by users looking for increased alertness, weight loss or athletic performance.

Prosaposin: a protein with differential sorting and multiple functions.

In eukaryotes the delivery of newly synthesized proteins to their final destination is dependent on a series of functionally distinct compartments, including the endoplasmic reticulum and the Golgi apparatus, which plays a role in post-translational modification, sorting and distribution of proteins. Most cargo is sorted within, and exits from, the trans-Golgi network (TGN). Proteins delivered to lysosomes include hydrolytic enzymes and nonenzymic activator proteins.

Amphetamine potentiates the effects of β-phenylethylamine through activation of an amine-gated chloride channel.

β-Phenylethylamine (βPEA) is a trace amine present in the CNS of all animals tested to date. However, its function is still not fully understood. βPEA has been suggested to function as a neurotransmitter and/or to mimic the effect of amphetamine (Amph).

β-Phenylethylamine requires the dopamine transporter to increase extracellular dopamine in Caenorhabditis elegans dopaminergic neurons.

β-Phenylethylamine (βPEA) is an endogenous amine that has been shown to increase the synaptic levels of dopamine (DA). A number of in vitro and behavioral studies suggest the dopamine transporter (DAT) plays a role in the effects generated by βPEA, however the mechanism through which βPEA affects DAT has not yet been elucidated. Here, we used Caenorhabditis (C.

Amphetamine activates an amine-gated chloride channel to generate behavioral effects in Caenorhabditis elegans.

Amphetamine is a highly addictive psychostimulant, which is thought to generate its effects by promoting release of dopamine through reverse activation of dopamine transporters. However, some amphetamine-mediated behaviors persist in dopamine transporter knock-out animals, suggesting the existence of alternative amphetamine targets. Here we demonstrate the identification of a novel amphetamine target by showing that in Caenorhabditis elegans, a large fraction of the behavioral effects of amphetamine is mediated through activation of the amine-gated chloride channel, LGC-55.