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Aims: Alzheimer's disease (AD) is a devastating dementia characterized by extracellular amyloid‐β (Aβ) protein aggregates and intracellular tau protein deposition. Clinically available drugs mainly target acetylcholinesterase (AChE) and indirectly sustain cholinergic neuronal tonus. Butyrylcholinesterase (BChE) also controls acetylcholine (ACh) turnover and is involved in the formation of Aß aggregates and senile plaques. UW‐MD‐95 is a novel carbamate‐based compound acting as a potent pseudo‐irreversible BChE inhibitor, with high selectivity versus AChE, and showing promising protective potentials in AD. Methods: We characterized the neuroprotective activity of UW‐MD‐95 in mice treated intracerebroventricularly with oligomerized Aβ25‐35 peptide using behavioral, biochemical, and immunohistochemical approaches. Results: When injected acutely 30 min before the behavioral tests (spontaneous alternation in the Y‐maze, object recognition, or passive avoidance), UW‐MD‐95 (0.3‐3 mg/kg) showed anti‐amnesic effects in Aβ25‐35‐treated mice. When injected once a day over 7 days, it prevented Aβ25‐35‐induced memory deficits. This effect was lost in BChE knockout mice. Moreover, the compound prevented Aβ25‐35‐induced oxidative stress (assessed by lipid peroxidation or cytochrome c release), neuroinflammation (IL‐6 and TNFα levels or GFAP and IBA1 immunoreactivity) in the hippocampus and cortex, and apoptosis (Bax level). Moreover, UW‐MD‐95 significantly reduced the increase in soluble Aβ1‐42 level in the hippocampus induced by Aβ25‐35. Conclusion: UW‐MD‐95 appeared as a potent neuroprotective compound in the Aβ25‐35 model of AD, with potentially an impact on Aβ1‐42 accumulation that could suggest a novel mechanism of neuroprotection. [ABSTRACT FROM AUTHOR]

Mouse adrenal SEC-associated genes are expressed at significantly higher levels in the adrenal gland (Supporting information Figure S4A) and include a higher percentage of tissue-specific genes (Supporting information Figure S4B) than TEC-associated genes. We report here that the pituitary hormone prolactin (PRL) has an important, conserved role in regulating adrenal gland function. 9 Glasow A, Breidert M, Haidan A, Anderegg U, Kelly PA, Bornstein SR. Functional aspects of the effect of prolactin (PRL) on adrenal steroidogenesis and distribution of the PRL receptor in the human adrenal gland. [Extracted from the article]

Tight control of the concentration of acetylcholine at cholinergic synapses requires precise regulation of the number and state of the acetylcholine receptors, and of the synthesis and degradation of the neurotransmitter. In particular, the cholinesterase activity has to be controlled exquisitely. In the genome of the first experimental models used (man, mouse, zebrafish and drosophila), there are only one or two genes coding for cholinesterases, whereas there are more genes for their closest relatives the carboxylesterases. Natural amplification of cholinesterase genes was first found to occur in some cancer cells and in insect species subjected to evolutionary pressure by insecticides. Analysis of the complete genome sequences of numerous representatives of the various metazoan phyla show that moderate amplification of cholinesterase genes is not uncommon in molluscs, echinoderms, hemichordates, prochordates or lepidosauria. Amplification of acetylcholinesterase genes is also a feature of parasitic nematodes or ticks. In these parasites, over-production of cholinesterase-like proteins in secreted products and the saliva are presumed to have effector roles related to host infection. These amplification events raise questions about the role of the amplified gene products, and the adaptation processes necessary to preserve efficient cholinergic transmission. This is an article for the . [ABSTRACT FROM AUTHOR]

ABSTRACT As the volume of data relating to proteins increases, researchers rely more and more on the analysis of published data, thus increasing the importance of good access to these data that vary from the supplemental material of individual articles, all the way to major reference databases with professional staff and long-term funding. Specialist protein resources fill an important middle ground, providing interactive web interfaces to their databases for a focused topic or family of proteins, using specialized approaches that are not feasible in the major reference databases. Many are labors of love, run by a single lab with little or no dedicated funding and there are many challenges to building and maintaining them. This perspective arose from a meeting of several specialist protein resources and major reference databases held at the Wellcome Trust Genome Campus (Cambridge, UK) on August 11 and 12, 2014. During this meeting some common key challenges involved in creating and maintaining such resources were discussed, along with various approaches to address them. In laying out these challenges, we aim to inform users about how these issues impact our resources and illustrate ways in which our working together could enhance their accuracy, currency, and overall value. Proteins 2015; 83:1005-1013. © 2015 The Authors. Proteins: Structure, Function, and Bioinformatics Published by Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Introduction: The effects of locomotor training (LT) on skeletal muscle after peripheral nerve injury and acetylcholinesterase deficiency are not well documented. Methods: We determined the effects of LT on mouse soleus muscle performance after sciatic nerve transection with excision (full and permanent denervation), nerve transection (partial functional reinnervation), nerve crush (full denervation with full functional reinnervation), and acetylcholinesterase deficiency (alteration in neuromuscular junction functioning). Results: We found no significant effect of LT on the recovery of soleus muscle weight, maximal force in response to muscle stimulation, and fatigue resistance after nerve transection with or without excision. However, LT significantly increased soleus muscle fatigue resistance after nerve crush and acetylcholinesterase deficiency. Moreover, hindlimb immobilization significantly aggravated the deficit in soleus muscle maximal force production and atrophy after nerve crush. Conclusions: LT is beneficial, and reduced muscle use is detrimental for intrinsic muscle performance in the context of disturbed nerve-muscle communication. Muscle Nerve, 2012 [ABSTRACT FROM AUTHOR]

Thyroid hormones (TH, including the prohormone thyroxine (T4) and its active deiodinated derivative 3,3',5-triiodo-L-thyronine (T3)) are important regulators of vertebrates neurodevelopment. Specific transporters and deiodinases are required to ensure T3 access to the developing brain. T3 activates a number of differentiation processes in neuronal and glial cell types by binding to nuclear receptors, acting directly on transcription. Only few T3 target genes are currently known. Deeper investigations are urgently needed, considering that some chemicals present in food are believed to interfere with T3 signaling with putative neurotoxic consequences. [ABSTRACT FROM AUTHOR]

To learn more about the evolution of the cholinesterases (ChEs), acetylcholinesterase (AChE) and butyrylcholinesterase in the vertebrates, we investigated the AChE activity of a deuterostome invertebrate, the urochordate Ciona intestinalis, by expressing in vitro a synthetic recombinant cDNA for the enzyme in COS-7 cells. Evidence from kinetics, pharmacology, molecular biology, and molecular modeling confirms that the enzyme is AChE. Sequence analysis and molecular modeling also indicate that the cDNA codes for the AChET subunit, which should be able to produce all three globular forms of AChE: monomers (G1), dimers (G2), and tetramers (G4), and assemble into asymmetric forms in association with the collagenic subunit collagen Q. Using velocity sedimentation on sucrose gradients, we found that all three of the globular forms are either expressed in cells or secreted into the medium. In cell extracts, amphiphilic monomers (G1a) and non-amphiphilic tetramers (G4na) are found. Amphiphilic dimers (G2a) and non-amphiphilic tetramers (G4na) are secreted into the medium. Co-expression of the catalytic subunit with Rattus norvegicus collagen Q produces the asymmetric A12 form of the enzyme. Collagenase digestion of the A12 AChE produces a lytic G4 form. Notably, only globular forms are present in vivo. This is the first demonstration that an invertebrate AChE is capable of assembling into asymmetric forms. We also performed a phylogenetic analysis of the sequence. We discuss the relevance of our results with respect to the evolution of the ChEs in general, in deuterostome invertebrates, and in chordates including vertebrates. [ABSTRACT FROM AUTHOR]

Hyperpnoeic episodic breathing (HEB), a cyclic waxing and waning of breathing, has been widely reported in pre-term neonates, patients with Joubert syndrome and adults (Cheyne-Stokes respiration) with congestive heart failure and brainstem infarction. We now provide a developmental mouse model of neonatal HEB. We used retinoic acid (RA) (0.5–10 mg/kg of maternal weight) to alter embryonic development of the respiratory neuronal network at the onset of hindbrain segmentation (7.5 days post-coitum). HEB was observed in vivo after RA treatment during post-natal days 1–7 but not in control animals. HEB persisted after reduction of the chemoafferent input by hypocapnic hyperoxia (100% O2). A large increase and decrease of the rhythm resembling an HEB episode was induced in vitro by stimulating the parafacial respiratory oscillator in treated but not in control neonates. Post-natal localization of the superior cerebellar peduncle and adjacent dorsal tegmentum was found to be abnormal in the pons of RA-treated juvenile mice. Thus, early developmental specifications in the rostral hindbrain are required for the development of neurones that stabilize the function of the respiratory rhythm generator, thereby preventing HEB during post-natal maturation. [ABSTRACT FROM AUTHOR]

Discusses the non-catalytic functions of acetylcholinesterases in mutant animal models. Clearance of released neurotransmitter at cholinergic synapses; Comparison of in vivo studies on invertebrate and vertebrate genetic models; Appearance of phenotypes following the loss of function of ache in the biological systems.

1 The present study was performed to evaluate the presence and the physiological consequences of butyrylcholinesterase (BChE) inhibition on isolated phrenic-hemidiaphragm preparations from normal mice expressing acetylcholinesterase (ACHE) and BChE, and from AChE-knockout mice (ACHE[sup -/-]) expressing only BChE. 2 Histochemical and enzymatic assays revealed abundance of AChE and BChE in normal mature neuromuscular junctions (NMJs). 3 In normal NMJs, in which release was reduced by low Ca[sup 2+]/high Mg[sup 2+] medium BChE inhibition with tetraisopropylpyrophosphoramide (iso-OMPA) or bambuterol decreased (∼50%) evoked quantal release, while inhibition of AChE with fasciculin-l, galanthamine (10, 20 µM) or neostigmine (0.1-1 µM) increased (50-80%) evoked quantal release. Inhibition of both AChE and BChE with galanthamine (80 µM), neostigmine (3-10 µM), O-ethylS-2-(diisopropylamino)ethyl-methylphosphonothioate (MTP) or phospholine decreased evoked transmitter release (20-50%). 4 In AChE[sup -/-] NMJs, iso-OMPA pre-treatment decreased evoked release. 5 Muscarinic toxin-3 decreased evoked release in both AChE[sup -/-] and normal NMJs treated with low concentrations of neostigmine, galanthamine or fasciculin-1, but had no effect in normal NMJs pretreated with iso-OMPA, bambuterol, MTP and phospholine. 6 In normal and AChE[sup -/-] NMJs pretreatment with iso-OMPA failed to affect the time course of miniature endplate potentials and full-sized endplate potentials. 7 Overall, our results suggest that inhibition or absence of AChE increases evoked quantal release by involving muscarinic receptors (mAChRs), while BChE inhibition decreases release through direct or indirect mechanisms not involving mAChRs. BChE apparently is not implicated in limiting the duration of acetylcholine action on postsynaptic receptors, but is involved in a presynaptic modulatory step of the release process. [ABSTRACT FROM AUTHOR]

Abstract During embryonic development, restricted expression of the regulatory genes Krox20 and kreisler are involved in segmentation and antero-posterior patterning of the hindbrain neural tube. The analysis of transgenic mice in which specific rhombomeres (r) are eliminated points to an important role of segmentation in the generation of neuronal networks controlling vital rhythmic behaviours such as respiration. Thus, elimination of r3 and r5 in Krox20 –/– mice suppresses a pontine antiapneic system (Jacquin et al ., 1996). We now compare Krox20 –/– to kreisler heterozygous (+/kr ) and homozygous (kr/kr ) mutant neonates. In +/kr mutant mice, we describe hyperactivity of the antiapneic system: analysis of rhythm generation in vitro revealed a pontine modification in keeping with abnormal cell specifications previously reported in r3 (Manzanares et al ., 1999b). In kr/kr mice, elimination of r5 abolished all +/kr respiratory traits, suggesting that +/kr hyperactivity of the antiapneic system is mediated through r5-derived territories. Furthermore, collateral chemosensory pathways that normally mediate delayed responses to hypoxia and hyperoxia were not functional in kr/kr mice. We conclude that the pontine antiapneic system originates from r3r4, but not r5. A different rhythm-promoting system originates in r5 and kreisler controls the development of antiapneic and chemosensory signal transmission at this level. [ABSTRACT FROM AUTHOR]

A large cDNA fragment covering the complete sequence of the mature catalytic subunit of rabbit acetylcholinesterase (AChE) has been cloned and sequenced. This sequence was compared to that of rabbit butyrylcholinesterase (BChE; Jbilo, O. & Chatonnet, A. (1990) Nucleic Acids Res. 18, 3990). Amino acid sequences of AChE and BChE have 51% identity. They both possessed a choline-binding site W84, a catalytic triad S200-H440-E327 and six cysteine residues (positions 67-94, 254-265, 402-521) in conserved sequence positions to those that form three intrachain disulfide bonds in all cholinesterases (by convention, numbering of amino acids is that used for Torpedo AChE). Rabbit AChE had a larger number of aromatic residues lining the active-site gorge than rabbit BChE (14 compared to 8, respectively) and a smaller number of potential N-glycosylation sites (3 compared to 8, respectively). Both catalytic subunits have a hydrophilic C-terminus (catalytic subunits of type T). Expression of acetylcholinesterase and butyrylcholinesterase genes (ACHE and BCHE) was studied in rabbit tissues and during development by a correlation of Northern-blot analysis and enzymic activities. This correlation was rendered difficult by the presence of an eserine-resistant esterase active on butyrylthiocholine in serum, liver and lung. When the contribution of this carboxylesterase was taken into account, brain was found as the richest source of BChE followed by lung and heart. Rabbit liver had a very low content of BChE that correlated with the low BChE activity in plasma. During development, BCHE transcripts were detected as early as day 10 post coitum, whereas ACHE transcripts appeared only on day 12. [ABSTRACT FROM AUTHOR]

Abstract Cholinergic neurotransmission ensures muscle contraction and plays a role in the regulation of respiratory pattern in the brainstem. Inactivation of acetylcholinesterase (AChE) by organophosphates produces respiratory failure but AChE knockout mice survive to adulthood. Respiratory adaptation mechanisms which ensure survival of these mice were examined in vivo by whole body plethysmography and in vitro in the neonatal isolated brainstem preparation. AChE[sup -/-] mice presented no AChE activity but unaffected butyrylcholinesterase (BChE) activity. In vivo , bambuterol (50–500 µg/kg s.c.) decreased BChE activity peripherally but not in brain tissue and induced apnea and death in adult and neonate AChE[sup -/-] mice without affecting littermate AChE[sup +/+] and [sup +/-] animals. In vitro , bath-applied bambuterol (1–100 µm) and tetraisopropylpyrophosphoramide (10–100 µm) decreased BChE activity in the brainstem but did not perturb central respiratory activity recorded from spinal nerve rootlets. In vitro , the cholinergic agonists muscarine (50–100 µm) and nicotine (0.5–10 µm) induced tonic activity in respiratory motoneurons and increased the frequency of inspiratory bursts in AChE[sup +/+] and [sup +/-] animals. These effects were greatly attenuated in AChE[sup -/-] animals. The results suggest that, in mice lacking AChE, (i) BChE becomes essential for survival peripherally but plays no critical role in central rhythm-generating structures and (ii) a major adaptive mechanism for respiratory survival is the down-regulated response of central respiratory-related neurons and motoneurons to muscarinic and nicotinic agonists. [ABSTRACT FROM AUTHOR]