A 72-hour high fat diet increases transcript levels of the neuropeptide galanin in the dorsal hippocampus of the rat.

Background: Recent evidence identifies the hippocampus, a brain structure commonly associated with learning and memory, as key to the regulation of food intake and the development and consequences of obesity. Intake of a high fat diet (HFD) results in altered consumptive behavior, hippocampal damage, and cognitive deficits. While many studies report the effects of HFD after chronic consumption and in the instance of obesity, few examine the events that occur following acute HFD consumption.

Externalizing proneness and brain response during pre-cuing and viewing of emotional pictures.

Externalizing proneness, or trait disinhibition, is a concept relevant to multiple high-impact disorders involving impulsive-aggressive behavior. Its mechanisms remain disputed: major models posit hyperresponsive reward circuitry or heightened threat-system reactivity as sources of disinhibitory tendencies. This study evaluated alternative possibilities by examining relations between trait disinhibition and brain reactivity during preparation for and processing of visual affective stimuli.

HemQ: An iron-coproporphyrin oxidative decarboxylase for protoheme synthesis in Firmicutes and Actinobacteria.

Genes for chlorite dismutase-like proteins are found widely among heme-synthesizing bacteria and some Archaea. It is now known that among the Firmicutes and Actinobacteria these proteins do not possess chlorite dismutase activity but instead are essential for heme synthesis. These proteins, named HemQ, are iron-coproporphyrin (coproheme) decarboxylases that catalyze the oxidative decarboxylation of coproheme III into protoheme IX.

Chronic exercise dampens hippocampal glutamate overflow induced by kainic acid in rats.

Our laboratory has previously reported that chronic, voluntary exercise diminishes seizure-related behaviors induced by convulsant doses of kainic acid. The present experiments tested the hypothesis that exercise exerts this protective effect through a mechanism involving suppression of glutamate release in the hippocampal formation. Following three weeks of voluntary wheel running or sedentary conditions, rats were injected with 10 mg/kg of kainic acid, and hippocampal glutamate was measured in real time using a telemetric, in vivo voltammetry system.

Noncanonical coproporphyrin-dependent bacterial heme biosynthesis pathway that does not use protoporphyrin.

It has been generally accepted that biosynthesis of protoheme (heme) uses a common set of core metabolic intermediates that includes protoporphyrin. Herein, we show that the Actinobacteria and Firmicutes (high-GC and low-GC Gram-positive bacteria) are unable to synthesize protoporphyrin. Instead, they oxidize coproporphyrinogen to coproporphyrin, insert ferrous iron to make Fe-coproporphyrin (coproheme), and then decarboxylate coproheme to generate protoheme.

Prevention of palatable diet-induced hyperphagia in rats by central injection of a VEGFR kinase inhibitor.

Our previous studies have demonstrated a critical role of a VEGFR-like signaling pathway in hunger-driven overeating of sugar-rich food in Drosophila larvae. In the current study, we investigate whether the VEGFR signaling mechanism plays a similar role in the feeding behavior of vertebrates using male Sprague Dawley rats. Young rats were treated intracerebroventrically (i.

Galanin mediates features of neural and behavioral stress resilience afforded by exercise.

Exercise promotes resilience to stress and increases galanin in the locus coeruleus (LC), but the question of whether changes in galanin signaling mediate the stress-buffering effects of exercise has never been addressed. To test the contributions of galanin to stress resilience, male Sprague Dawley rats received intracerebroventricular (ICV) cannulation for drug delivery and frontocortical cannulation for microdialysis, and were housed with or without a running wheel for 21d. Rats were acutely injected with vehicle or the galanin receptor antagonist M40 and exposed to a single session of either footshock or no stress.

Trophic Mechanisms for Exercise-Induced Stress Resilience: Potential Role of Interactions between BDNF and Galanin.

Current concepts of the neurobiology of stress-related disorders, such as anxiety and depression emphasize disruptions in neural plasticity and neurotrophins. The potent trophic actions of exercise, therefore, represent not only an effective means for prevention and treatment of these disorders, they also afford the opportunity to employ exercise paradigms as a basic research tool to uncover the neurobiological mechanisms underlying these disorders. Novel approaches to studying stress-related disorders focus increasingly on trophic factor signaling in corticolimbic circuits that both mediate and regulate cognitive, behavioral, and physiological responses to deleterious stress.

Yogic breathing and Ayurveda in aphasia: a case study.

Purpose: We present a case study of a woman who used yogic breathing as Ayurvedic medicine in her recovery from poststroke aphasia. Ayurvedic medicine is one of the most ancient medicines of the world, but it is not widely used for aphasia rehabilitation in many Western countries. The description of this case aims to further the understanding of the benefits that this type of medicine may provide to poststroke patients living with aphasia.

Octopamine-mediated circuit mechanism underlying controlled appetite for palatable food in Drosophila.

The easy accessibility of energy-rich palatable food makes it difficult to resist food temptation. Drosophila larvae are surrounded by sugar-rich food most of their lives, raising the question of how these animals modulate food-seeking behaviors in tune with physiological needs. Here we describe a circuit mechanism defined by neurons expressing tdc2-Gal4 (a tyrosine decarboxylase 2 promoter-directed driver) that selectively drives a distinct foraging strategy in food-deprived larvae.

Erythroid heme biosynthesis and its disorders.

Heme, which is composed of iron and the small organic molecule protoporphyrin, is an essential component of hemoglobin as well as a variety of physiologically important hemoproteins. During erythropoiesis, heme synthesis is induced before, and is essential for, globin synthesis. Although all cells possess the ability to synthesize heme, there are distinct differences between regulation of the pathway in developing erythroid cells and all other types of cells.

Neuropeptide-gated perception of appetitive olfactory inputs in Drosophila larvae.

Understanding how smell or taste translates into behavior remains challenging. We have developed a behavioral paradigm in Drosophila larvae to investigate reception and processing of appetitive olfactory inputs in higher-order olfactory centers. We found that the brief presentation of appetitive odors caused fed larvae to display impulsive feeding of sugar-rich food.

Mutations in Bacchus reveal a tyramine-dependent nuclear regulator for acute ethanol sensitivity in Drosophila.

Fruit flies and humans display remarkably similar behavioral responses to ethanol intoxication. Here we report that loss-of-function mutations in the CG9894 gene (now named Bacchus or Bacc) attenuate ethanol sensitivity in flies. Bacc encodes a broadly expressed nuclear protein with a motif similar to ribosomal RNA-binding domains.

Activation of type 5 metabotropic glutamate receptors and diacylglycerol lipase-α initiates 2-arachidonoylglycerol formation and endocannabinoid-mediated analgesia.

Acute stress reduces pain sensitivity by engaging an endocannabinoid signaling circuit in the midbrain. The neural mechanisms governing this process and molecular identity of the endocannabinoid substance(s) involved are unknown. We combined behavior, pharmacology, immunohistochemistry, RNA interference, quantitative RT-PCR, enzyme assays, and lipidomic analyses of endocannabinoid content to uncover the role of the endocannabinoid 2-arachidonoyl-sn-glycerol (2-AG) in controlling pain sensitivity in vivo.

Exercise offers anxiolytic potential: a role for stress and brain noradrenergic-galaninergic mechanisms.

Although physical activity reduces anxiety in humans, the neural basis for this response is unclear. Rodent models are essential to understand the mechanisms that underlie the benefits of exercise. However, it is controversial whether exercise exerts anxiolytic-like potential in rodents.

Identification and characterization of solvent-filled channels in human ferrochelatase.

Ferrochelatase catalyzes the formation of protoheme from two potentially cytotoxic products, iron and protoporphyrin IX. While much is known from structural and kinetic studies on human ferrochelatase of the dynamic nature of the enzyme during catalysis and the binding of protoporphyrin IX and heme, little is known about how metal is delivered to the active site and how chelation occurs. Analysis of all ferrochelatase structures available to date reveals the existence of several solvent-filled channels that originate at the protein surface and continue to the active site.

The Escherichia coli protein YfeX functions as a porphyrinogen oxidase, not a heme dechelatase.

Unlabelled: The protein YfeX from Escherichia coli has been proposed to be essential for the process of iron removal from heme by carrying out a dechelation of heme without cleavage of the porphyrin macrocycle. Since this proposed reaction is unique and would represent the first instance of the biological dechelation of heme, we undertook to characterize YfeX. Our data reveal that YfeX effectively decolorizes the dyes alizarin red and Cibacron blue F3GA and has peroxidase activity with pyrogallal but not guiacol.

An overview of brain-derived neurotrophic factor and implications for excitotoxic vulnerability in the hippocampus.

The present paper examines the nature and function of brain-derived neurotrophic factor (BDNF) in the hippocampal formation and the consequences of changes in its expression. The paper focuses on literature describing the role of BDNF in hippocampal development and neuroplasticity. BDNF expression is highly sensitive to developmental and environmental factors, and increased BDNF signaling enhances neurogenesis, neurite sprouting, electrophysiological activity, and other processes reflective of a general enhancement of hippocampal function.

Discovery of a gene involved in a third bacterial protoporphyrinogen oxidase activity through comparative genomic analysis and functional complementation.

Tetrapyrroles are ubiquitous molecules in nearly all living organisms. Heme, an iron-containing tetrapyrrole, is widely distributed in nature, including most characterized aerobic and facultative bacteria. A large majority of bacteria that contain heme possess the ability to synthesize it.

Pharmacological characterization of AM1710, a putative cannabinoid CB2 agonist from the cannabilactone class: antinociception without central nervous system side-effects.

Cannabinoid CB(2) agonists produce antinociception without central nervous system (CNS) side-effects. This study was designed to characterize the pharmacological and antinociceptive profile of AM1710, a CB(2) agonist from the cannabilactone class of cannabinoids. AM1710 did not exhibit off-target activity at 63 sites evaluated.

Locus coeruleus galanin expression is enhanced after exercise in rats selectively bred for high capacity for aerobic activity.

The neuropeptide galanin extensively coexists with norepinephrine in locus coeruleus (LC) neurons. Previous research in this laboratory has demonstrated that unlimited access to activity wheels in the home cage increases mRNA for galanin (GAL) in the LC, and that GAL mediates some of the beneficial effects of exercise on brain function. To assess whether capacity for aerobic exercise modulates this upregulation in galanin mRNA, three heterogeneous rat models were tested: rats selectively bred for (1) high intrinsic (untrained) aerobic capacity (High Capacity Runners, HCR) and (2) low intrinsic aerobic capacity (Low Capacity Runners, LCR) and (3) unselected Sprague-Dawley (SD) rats with and without free access to running wheels for 3 weeks.

Discovery and Characterization of HemQ: an essential heme biosynthetic pathway component.

Here we identify a previously undescribed protein, HemQ, that is required for heme synthesis in Gram-positive bacteria. We have characterized HemQ from Bacillus subtilis and a number of Actinobacteria. HemQ is a multimeric heme-binding protein.