NO-dependent protective effect of VEGF against excitotoxicity on layer VI of the developing cerebral cortex.

In industrialized countries, cerebral palsy affects 2.5‰ of preterm and term infants. At a neurochemical level, the massive release of glutamate constitutes a major process leading to excitotoxicity and neonatal brain lesions.

Effect of unilateral subthalamic deep brain stimulation on rat digestive motor activity.

Unlabelled: A significant proportion of patients with Parkinson's disease suffers from digestive symptoms. Bilateral deep brain stimulation of the subthalamic nucleus has become a reliable therapeutic option for parkinsonian patients, but its effects on digestive motility remain poorly investigated. The aim of our study was to assess whether subthalamic stimulation could induce changes in gastric, colonic, and rectal motility and modulate brain centers involved in gut motility.

Structure-activity relationships of a series of analogues of the RFamide-related peptide 26RFa.

26RFa is a new member of the RFamide peptide family that has been identified as the endogenous ligand of the orphan GPCR GPR103. As the C-terminal heptapeptide (26RFa((20-26))) mimics the action of the native peptide on food intake and gonadotropin secretion in rodents, we have synthesized a series of analogues of 26RFa((20-26)) and measured their potency to induce [Ca(2+)](i) mobilization in Gα(16)-hGPR103-transfected CHO cells. Systematic replacement of each residue by an alanine (Ala scan) and its D-enantiomer (D scan) showed that the last three C-terminal residues were very sensitive to the substitutions while position 23 tolerated rather well both modifications.

Rumination syndrome: when the lower oesophageal sphincter rises.

Background: Rumination syndrome is an uncommon condition characterised by the self-induced regurgitation from the stomach to the mouth of recently ingested meal that is chewed and reswallowed. Rumination is caused by a voluntary rise in intra-abdominal and intra-gastric pressure leading to the reflux of the gastric content into the oesophagus. However, the precise mechanisms preventing reflux at the gastro-oesophageal junction during the rise in intra-gastric pressure remains unknown.

Transplantation of olfactory ensheathing cells promotes axonal regeneration and functional recovery of peripheral nerve lesion in rats.

Introduction: Olfactory ensheathing cells (OECs) hold promise for cell therapy because they may promote regeneration of the central nervous system. However, OECs have been less studied after peripheral nerve injury (PNI). The purpose of this investigation was to determine the effect of OEC transplantation on a severe sciatic nerve (SN) lesion.

Neurosteroid biosynthesis in the brain of amphibians.

Amphibians have been widely used to investigate the synthesis of biologically active steroids in the brain and the regulation of neurosteroid production by neurotransmitters and neuropeptides. The aim of the present review is to summarize the current knowledge regarding the neuroanatomical distribution and biochemical activity of steroidogenic enzymes in the brain of anurans and urodeles. The data accumulated over the past two decades demonstrate that discrete populations of neurons and/or glial cells in the frog and newt brains express the major steroidogenic enzymes and are able to synthesize de novo a number of neurosteroids from cholesterol/pregnenolone.

Efficiency of laryngeal motor nerve repair is greater with bulbar than with mucosal olfactory ensheathing cells.

The real ability of OECs provided by olfactory mucosa cultures (OM-OECs) and those from olfactory bulb cultures (OB-OECs) must be better characterized in order to propose their future clinical application. Therefore, we used a lesion of the vagus nerve (VN), which constitutes a severe motor denervation due to long distance of the muscular targets (4.5 cm).

Effects of essential amino acids or glutamine deprivation on intestinal permeability and protein synthesis in HCT-8 cells: involvement of GCN2 and mTOR pathways.

GCN2 and mTOR pathways are involved in the regulation of protein metabolism in response to amino acid availability in different tissues. However, regulation at intestinal level is poorly documented. The aim of the study was to evaluate the effects of a deprivation of essential amino acids (EAA) or glutamine (Gln) on these pathways in intestinal epithelial cells.

Beneficial effects of cathepsin inhibition to prevent chemotherapy-induced intestinal mucositis.

One of the main secondary toxic side effects of anti-mitotic agents used to treat cancer patients is intestinal mucositis. Previous data showed that cathepsin D activity, contributing to the proteolytic lysosomal pathway, is up-regulated during intestinal mucositis in rats. At the same time, cathepsin inhibition limits intestinal damage in animal models of inflammatory bowel diseases.

Urotensin II, from fish to human.

The cyclic peptide urotensin II (UII) was originally isolated from the urophysis of teleost fish on the basis of its ability to contract intestinal smooth muscle. The UII peptide has subsequently been isolated from frog brain and, later on, the pre-proUII cDNA has been characterized in mammals, including humans. A UII paralog called urotensin II-related peptide (URP) has been identified in the rat brain.

Granins and their derived peptides in normal and tumoral chromaffin tissue: Implications for the diagnosis and prognosis of pheochromocytoma.

Pheochromocytomas are rare catecholamine-secreting tumors that arise from chromaffin tissue within the adrenal medulla and extra-adrenal sites. Typical clinical manifestations are sustained or paroxysmal hypertension, severe headaches, palpitations and sweating resulting from hormone excess. However, their presentation is highly variable and can mimic many other diseases.

Comparative gene expression profiling of olfactory ensheathing cells from olfactory bulb and olfactory mucosa.

Olfactory ensheathing cells (OEC) have the ability to promote regeneration in the nervous system. Hence, they hold promise for cell therapy. Most of the experimental studies have investigated the role of OECs taken from olfactory bulb (OB).

Prolyl endopeptidase mRNA expression in the central nervous system during rat development.

Prolyl endopeptidase (PEP) is a serine protease that cleaves small peptides at the carboxyl side of L-proline. PEP has been reported to have important functions in the brain being implicated in learning and memory processes, psychological disorders and neurodegenerative diseases. Several PEP substrates have been shown to play a role during brain development and this observation led us to investigate the expression of PEP mRNA in the rat brain and spinal cord, from embryo to adult stages.

Acute food deprivation reduces expression of diazepam-binding inhibitor, the precursor of the anorexigenic octadecaneuropeptide ODN, in mouse glial cells.

In the central nervous system of mammals, the gene encoding diazepam-binding inhibitor (DBI) is exclusively expressed in glial cells. Previous studies have shown that central administration of a DBI processing product, the octadecaneuropeptide ODN, causes a marked inhibition of food consumption in rodents. Paradoxically, however, the effect of food restriction on DBI gene expression has never been investigated.

The vasoactive peptides urotensin II and urotensin II-related peptide regulate astrocyte activity through common and distinct mechanisms: involvement in cell proliferation.

UII (urotensin II) and its paralogue URP (UII-related peptide) are two vasoactive neuropeptides whose respective central actions are currently unknown. In the present study, we have compared the mechanism of action of URP and UII on cultured astrocytes. Competition experiments performed with [125I]UII showed the presence of very-high- and high-affinity binding sites for UII, and a single high-affinity site for URP.

Structural and pharmacological characteristics of chimeric peptides derived from peptide E and beta-endorphin reveal the crucial role of the C-terminal YGGFL and YKKGE motifs in their analgesic properties.

Peptide E (a 25-amino acid peptide derived from proenkephalin A) and beta-endorphin (a 31-amino acid peptide derived from proopiomelanocortin) bind with high affinity to opioid receptors and share structural similarities but induce analgesic effects of very different intensity. Indeed, whereas they possess the same N-terminus Met-enkephalin message sequence linked to a helix by a flexible spacer and a C-terminal part in random coil conformation, in contrast with peptide E, beta-endorphin produces a profound analgesia. To determine the key structural elements explaining this very divergent opioid activity, we have compared the structural and pharmacological characteristics of several chimeric peptides derived from peptide E and beta-endorphin.

Balanced effect of PACAP and FasL on granule cell death during cerebellar development: a morphological, functional and behavioural characterization.

It is now established that the development of the CNS requires equilibrium between cell survival and apoptosis. Pituitary adenylate cyclase-activating polypeptide (PACAP) exerts a powerful protective effect on cerebellar granule cells by inhibiting the caspase 3. In contrast, Fas ligand (FasL) plays an essential role during ontogenesis in eliminating supernumerary neurons by apoptosis.

A diet containing whey protein, glutamine, and TGFbeta modulates gut protein metabolism during chemotherapy-induced mucositis in rats.

Background: Mucositis, a common side effect of chemotherapy, is characterized by compromised digestive function, barrier integrity and immune competence.

Aims: Our aim was to evaluate the impact of a specifically designed diet Clinutren Protect (CP), which contains whey proteins, TGFbeta-rich casein, and free glutamine, on mucositis in rats.

Methods: Mucositis was induced by three consecutive injections (day 0, day 1, day 2) of methotrexate (2.

Pituitary adenylate cyclase-activating polypeptide and its receptors: 20 years after the discovery.

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a 38-amino acid C-terminally alpha-amidated peptide that was first isolated 20 years ago from an ovine hypothalamic extract on the basis of its ability to stimulate cAMP formation in anterior pituitary cells (Miyata et al., 1989. PACAP belongs to the vasoactive intestinal polypeptide (VIP)-secretin-growth hormone-releasing hormone-glucagon superfamily.

Dual effect of glutamate on GABAergic interneuron survival during cerebral cortex development in mice neonates.

In term and preterm neonates, massive glutamate release can lead to excitotoxic white-matter and cortical lesions. Because of its high permeability toward calcium, the N-methyl-D-aspartic acid (NMDA) receptor is thought to play an important role in excitotoxic lesions and NMDA antagonists therefore hold promise for neuroprotection. We found that, in neonatal mouse cortex, a given NMDA concentration exerted either excitotoxic or antiapoptotic effects depending on the cortical layers.

Gastric electrical stimulation in intractable nausea and vomiting: assessment of predictive factors of favorable outcomes.

Background: Gastric electrical stimulation (GES) represents a new therapy in patients with intractable vomiting and nausea. We aimed to determine preoperative factors associated with positive response during GES. Thirty-three consecutive patients received implants for medically refractory nausea or vomiting or both.

Potential for amino acids supplementation during inflammatory bowel diseases.

The pathophysiology of inflammatory bowel diseases (IBDs) is multifactorial and involves interactions of gut luminal content with mucosal barrier and especially immune cells. Malnutrition is a frequent issue during IBD flares, especially in Crohn's disease (CD) patients, and nutritional support is frequently used to treat malnutrition but also in an attempt to modulate intestinal inflammation. The use of oral or enteral nutrition intervention in IBDs may be effective, alone or in combination with drugs, to achieve and maintain remission.

Paradoxical effect of ethanol on potassium channel currents and cell survival in cerebellar granule neurons.

Transient exposure to ethanol (EtOH) results in a massive neurodegeneration in the developing brain leading to behavioral and cognitive deficits observed in fetal alcohol syndrome. There is now compelling evidence that K+ channels play an important role in the control of programmed cell death. The aim of the present work was to investigate the involvement of K+ channels in the EtOH-induced cerebellar granule cell death and/or survival.

TRH acts as a multifunctional hypophysiotropic factor in vertebrates.

Thyrotropin-releasing hormone (TRH) is the first hypothalamic hypophysiotropic neuropeptide whose sequence has been chemically characterized. The primary structure of TRH (pGlu-His-Pro-NH(2)) has been fully conserved across the vertebrate phylum. TRH is generated from a large precursor protein that contains multiple repeats of the TRH progenitor tetrapeptide Gln-His-Pro-Gly.