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Lactate's role in the brain is understood as a contributor to brain energy metabolism, but it may also regulate the cerebral microcirculation. The purpose of this systematic review was to evaluate evidence of lactate as a physiological effector within the normal cerebral microcirculation in reports ranging from in vitro experiments to in vivo studies in animals and humans. Following pre‐registration of a review protocol, we systematically searched the PubMed, EMBASE, and Cochrane databases for literature covering themes of 'lactate', 'the brain', and 'microcirculation'. Abstracts were screened, and data extracted independently by two individuals. We excluded studies evaluating lactate in disease models. Twenty‐eight papers were identified, 18 of which were in vivo animal experiments (65%), four on human studies (14%), and six on in vitro or ex vivo experiments (21%). Approximately half of the papers identified lactate as an augmenter of the hyperemic response to functional activation by a visual stimulus or as an instigator of hyperemia in a dose‐dependent manner, without external stimulation. The mechanisms are likely to be coupled to NAD+/NADH redox state influencing the production of nitric oxide. Unfortunately, only 38% of these studies demonstrated any control for bias, which makes reliable generalizations of the conclusions insecure. This systematic review identifies that lactate may act as a dose‐dependent regulator of cerebral microcirculation by augmenting the hyperemic response to functional activation below 5 mmol/kg, and by initiating a hyperemic response above 5 mmol/kg. Open Science Badges: This article has received a badge for *Pre‐registration* because it made the data publicly available. The data can be accessed at www.radboudumc.nl/getmedia/53625326-d1df-432c-980f-27c7c80d1a90/THollyer%5flactate%5fprotocol.aspx. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/. This systematic review evaluated the role of lactate in the cerebral microcirculation across in vitro, in vivo, and clinical studies. We identified that when administered exogenously, at 5 mmol/kg or higher, lactate is an initiator of cerebral hyperemia and acts as an augmenter of functional hyperemia at lower doses. These findings shine light on novel aspects of lactate biochemistry in the brain. This manuscript was awarded with the Pre‐registration Badge. The pre‐registration protocol can be accessed at http://www.radboudumc.nl/getmedia/53625326-d1df-432c-980f-27c7c80d1a90/THollyer%5flactate%5fprotocol.aspx. For more information see: https://cos.io/our-services/open-science-badges/ [ABSTRACT FROM AUTHOR]

J. Neurochem. (2012) 122, 672-680. Abstract Choline acetyltransferase (ChAT) catalyzes the reaction between choline and acetylcoenzyme A (AcCoA) to form acetylcholine (ACh) in nerve terminals. ACh metabolism has implications in numerous aspects of physiology and varied disease states, such as Alzheimer's disease. Therefore a specific, sensitive, and reliable method for detecting ChAT enzyme activity is of great utility in a number of situations. Using an existing radionuclide-based enzyme activity assay, we have observed detectable ChAT signals from non-cholinergic cells, suggesting a contaminant in the assay producing an artifactual signal. Previous reports have suggested that L-acetylcarnitine (LAC) contaminates many assays of ChAT activity, because of difficulties in separating LAC from ACh by organic extraction. To determine the source of this hypothesized artifact and to rectify the problem, we have developed a paper chromatography-based assay for the detection of acetylcholine and other contaminating reaction products of this assay, including LAC. Our first goal was to develop a simple and economical method for resolving and verifying the identities of various reaction products or contaminants that could be performed in most laboratories without specialized equipment. Our second goal was to apply this separation method in postmortem human brain tissue samples. Our assay successfully detected several contaminants, especially in assays using brain tissue, and allowed the separation of the intended ACh product from these contaminants. We further demonstrate that this assay can be used to measure carnitine acetyltransferase (CrAT) activity in the same samples, and assays comparing ChAT and CrAT show that CrAT is highly active in neuronal tissues and in neuronal cell cultures relative to ChAT. Thus, the simple chromatography-based assay we describe allows the measurement of specific reaction products separated from contaminants using commonly available and inexpensive materials. Further, we show that ChAT activity is significantly reduced in brain extracts from Alzheimer's disease compared to controls. [ABSTRACT FROM AUTHOR]

Opiate drugs, such as codeine, morphine, and heroin, are powerful analgesics, but also are used as drugs of abuse because of their psychogenic properties. Many studies have shown that opiates impact on cellular proliferation in the adult and developing brain, although anatomical pathologies are lacking in in utero exposed infants and opioid knockout mice. Recent research has defined a context-dependent role for the opioid system in neurogenesis in the adult hippocampus with exercise. Opioids have been shown to interact with proliferating cells of the postnatal subventricular zone of the lateral ventricles. The subventricular zone is also a region of adult neurogenesis, a fact that was not well established at the time this earlier research was conducted. Although a relationship between opioids and fetal neurogenesis has yet to be firmly established, many studies have implicated the opioid system in this process. One common factor that links neurogenesis in adult, postnatal, and fetal structures is the involvement of neuronal progenitor cells of the astrocytic lineage. It is therefore of interest that opioids have been consistently shown to impact upon astrocytic proliferation. It is the intention of this paper to review the literature that has established a role for the opioid system in neurogenesis in vivo in fetal, postnatal, and adult animals and to examine the links of opioids to modulation of astrocytic proliferation. [ABSTRACT FROM AUTHOR]

Aggregation of α-synuclein, an abundant and conserved pre-synaptic brain protein, is implicated as a critical factor in several neurodegenerative diseases. These diseases, known as synucleinopathies, include Parkinson’s disease, dementia with Lewy bodies (LBs), diffuse LB disease, the LB variant of Alzheimer’s disease, multiple system atrophy, and neurodegeneration with brain iron accumulation type I. Although the precise nature of in vivoα-synuclein function remains elusive, considerable knowledge has been accumulated about its structural properties and conformational behavior. α-Synuclein is a typical natively unfolded protein. It is characterized by the lack of rigid, well-defined, 3-D structure and possesses remarkable conformational plasticity. The structure of this protein depends dramatically on its environment and it accommodates a number of unrelated conformations. This paper provides an overview of the biochemistry, biophysics, and neuropathology of α-synuclein aggregation. [ABSTRACT FROM AUTHOR]

Presents abstracts of papers featured in the "Journal of Neurochemistry" that deal with proliferation, survival and differentiation processes in cells. "Influence of prenatal irradiation by 131-I on the heparin-binding activity of newborn rat brain proteins"; Cannabinoid inhibition of neuronal differentiation".

The article presents abstracts of research papers on demyelination. They include "Acute depletion of glutathione leads to carbonylation of rat brain proteins," "Mechanism of protein s-nitrosylation in rat spinal cord," "Immediate early gene expression patterns map neuronal responses to cuprizone-induced demyelination," and "Lipoic acid inhibits expression of ICAM-1 and VCAM-1 by CNS endothelial cells and T cell migration into the spinal cord in EAE."

The article presents abstracts of research papers about the function of alpha-synuclein in brain physiology. They include "The role of alpha-synuclein in phosphatidylinositol signal transduction," "Synuclein as a mediator between synaptic membrane and cytoskeleton," "Mitochondrial lipid abnormality and electron transport chain impairment in mice lacking alpha-synuclein," and "Alpha-synuclein modulates brain fatty acid metabolism."

The article presents abstracts of research papers about mitochondrial neuochemistry. They include "Mitochondrial heterogeneity in brain," "Brain mitochondrial dysfunction—the critical event in neurodegeneration?," "Differential responses of astrocyte and neuronal mitochondria to calcium and oxidative stress," and "Proapoptotic mitochondrial signaling: the hows and whens."

The article presents an abstract of the medical research paper "Nitric Oxide Protects Brain Endothelial Cells Subjected to Oxidative Stress." The paper examined the role of nitric oxide (NO) and superoxide in blood-brain barrier. It has been discovered that NO may counterpart superoxide toxicity. NO reacts with oxygen radicals affording protection of cell membranes from peroxidation.

The article presents an abstract of the medical research paper "Temperature Dependencies of Oxygen Consumption by Rat Brain Tissue Homogenates at Hypothermia." The paper will be discussed at the Seventeenth Biennial Meeting of the International Society for Neurochemistry (ISN) and the Thirteenth General Meeting of the European Society for Neurochemistry (ESN) to be held in Berlin, Germany from August 8-14, 1999. It will determine adaptive changes in energy metabolism in rat brain.

The article presents an abstract of the medical research paper "Blood Platelets As Indicator of Disturbances of Acetyl-COA Metabolism in Diabetic Brain Neurons." The paper will be discussed at the Seventeenth Biennial Meeting of the International Society for Neurochemistry (ISN) and the Thirteenth General Meeting of the European Society for Neurochemistry (ESN) to be held in Berlin, Germany from August 8-14, 1999.

The article presents an abstract of the medical research paper "Immunocytochemical Localization of Glutathione Reductase in Cells of Neural Cultures." The paper will be discussed at the Seventeenth Biennial Meeting of the International Society for Neurochemistry (ISN) and the Thirteenth General Meeting of the European Society for Neurochemistry (ESN) to be held in Berlin, Germany from August 8-14, 1999. It will discuss the location of the enzyme Glutathione reductase in brain.

The article presents an abstract of the medical research paper "Ganglioside Administration to Mice Protects Brain Na,K-ATPase From Glutamate-Induced Inhibition." The paper will be discussed at the Seventeenth Biennial Meeting of the International Society for Neurochemistry (ISN) and the Thirteenth General Meeting of the European Society for Neurochemistry (ESN) to be held in Berlin, Germany from August 8-14, 1999.

The article presents an abstract of the medical research paper "Effect of Chronic Low Lead Dose on NCAM and GFAP levels in Different Region of Rat Brain Under Chronic X-Irradiation." The paper will be discussed at the Seventeenth Biennial Meeting of the International Society for Neurochemistry (ISN) and the Thirteenth General Meeting of the European Society for Neurochemistry (ESN) to be held in Berlin, Germany from August 8-14, 1999.

The article presents an abstract of the medical research paper "An Integrated Neuron-Glia Dialogue in the Processing of Brain Formation." The paper will be discussed at the Seventeenth Biennial Meeting of the International Society for Neurochemistry (ISN) and the Thirteenth General Meeting of the European Society for Neurochemistry (ESN) to be held in Berlin, Germany from August 8-14, 1999. The paper will discuss the role of astrocytes in the processing of brain formation.

The article presents an abstract of the medical research paper "Mouse Brain Neurons and Oligodendrocytes Express a Novel PLP/DM-20-Related Product." This paper is to be discussed in the Seventeenth Biennial Meeting of the International Society for Neurochemistry (ISN) and the Thirteenth General Meeting of the European Society for Neurochemistry (ESN) to be held at Berlin, Germany from August 8-14, 1999. This paper informs that PLP/DM-20 gene appears to be expressed in selected neurons.

The article presents an abstract of the medical research paper "Cytochrome P450 fo the 2B Subfamily in Rat Brain." The paper studies the constitutive expression of the P4502B subfamily in rat brain by applying a RT-PCR analysis of brain regions using nested primer probes for the P450 isoforms 2B1 and 2B2.

The article presents an abstract of the paper "High Integrity mRNA is Recovered From Brains of Rats Killed by High Energy Microwave Irradiation," which will be presented at the 30th Annual Meeting of the American Society for Neurochemistry to be held from March 14-17, 1999 in New Orleans, Louisiana. The paper suggests that by using microwave irradiation, the messenger RNA coherence will not get reduced, but it can be used to study various events in brains of experimental animals in vivo.

The article presents an abstract of the paper "Non-Invasive Assessment of the Diffusion Characteristics of Glucose in the Rat Brain in Vivo," which will be presented at the 30th Annual Meeting of the American Society for Neurochemistry to be held from March 14-17, 1999 in New Orleans, Louisiana. The paper concludes that the analysis of glucose in vivo during hyperglycemia is consistent with a considerable portion of glucose signal being intracellular.

The article presents an abstract of the paper "Ganglioside Patterns in Sleep-Related Subregions of Young and Aged Rat Brain," which will be presented at the 30th Annual Meeting of the American Society for Neurochemistry to be held from March 14-17, 1999 in New Orleans, Louisiana. The paper seeks to associate neurochemical patterns with neurophsiological processes, in analyzing age-related changes in the neural control of sleep.

The article presents the abstract of the paper "Effect of Hypoglycaemia and Ischaemia on Energetic Status of Primary Brain Cells." The paper will be presented at the 30th meeting of the American Society for Neurochemistry which is scheduled to be held from March 14-17, 1999. in New Orleans, Louisiana. The paper analyses the achievement of cell energization in hypoglycemia and ischaemia using Nuclear Magnetic Resonance techniques.

The article presents the abstract of the paper "Aerobic Lactate Utilization is Paramount for the Rescue of Brain Tissue Postischemia." The paper will be presented at the 30th meeting of the American Society for Neurochemistry which will be held from March 14-17, 1999 in New Orleans, Louisiana. The paper proves that lactate plays a vital role in the protection of neural tissues if given postischemia.

The article presents an abstract of the paper "Melatonin Exhibits Both Antioxidant and Pro-Oxidant Properties in a Mouse Brain Slice Model of Ischemia," which will be presented at the 30th Annual Meeting of the American Society for Neurochemistry to be held in New Orleans, Louisiana from March 14-17, 1999. The paper suggests that melatonin can be effective in protecting brain cells from excitotoxic insult by N-methyl-D-aspartate.

The article presents an abstract of the paper "Sensory Stimulation and Spreading Cortical Depression Stimulate Glial Citric Acid Cycle Activity," which will be presented at the 30th annual meeting of the American Society for Neurochemistry to be held from March 14-17, 1999 in New Orleans, Louisiana. The paper discusses the functional metabolic responses of glial cells to sensory stimulation. Glia are not glycolytic and can increase tricarboxylic acid cycle activity in working brain.

Presents abstracts of papers featured in the "Journal of Neurochemistry" that deal with developments in the knocking out of genes in the brain. "Proopiomelanocortin peptides and the regulation of energy homeostasis, reward, and stress responsiveness"; "Molecular and cellular cognition: lessons from mutant mice".

Presents abstracts of papers featured in the "Journal of Neurochemistry" that deal with glial function. "Glial communication studied in brain slices": "Roles of astrocytes-neuron cross talking on synaptic plasticity"; "A role for glia in the making and breaking of synapses".

The article presents an abstract of the research paper "Glutathione Metabolism and the Defence of Brain Cells Against Oxidative Stress." There appears a connection between oxidative stress and deficiency of the antioxidant glutathione in brain, and several diseases characterized by the neuronal loss.

The article presents an abstract of the research paper "Metabolic Abnormalities and Ischaemic Damage in the Mature Brain." A range of tissue damage determined by multiple factors including the severity and duration of insult is produced by cerebral ischaemia. Delayed death of selected neuronal subpopulations is caused by a short period of global ischaemia.

The article presents an abstract of the research paper "Neuropathology of the Developing Brain." There is a direct association between the pattern of damage and timing of insult. Damage in the first trimester leads to major malformations when the brain structures are forming. During neuronal migration, insults lead to heterotopias and cortical dysplasia.

The article presents an abstract of the research paper "Diet, lipids and brain development." Formation of a myelin sheath is one of the fundamental and necessary events in the normal development of the central nervous system in vertebrates. Myelinogenesis is basically a postnatal process in rodents.

The article presents an abstract of the research paper "Energy Metabolism in the Neonatal Human Brain." Unique insights into oxidative energy metabolism in the neonatal brain have been provided by phosphorus and proton magnetic resonance spectroscopy. A consistent rise in high energy phosphate concentrations with increasing maturity was observed as developmental changes.

The article presents an abstract of the research paper "Development of Rat Serotonergic Neurons from Various Raphe Subregions in Serum-Free Culture." The study determines a differential pattern in the development of the functional equipment in the various subgroups of serotonergic neurons. It determines that the serotonergic system is one of the earliest developing neurotransmitter systems in the mammalian brain.

The article presents an abstract of a research paper concerning regulation of brain derived neurotrophic factor (BDNF) gene expression in rat brain by chronic antipsychotic drug treatment. Rats received injections of either haloperidol, risperidone or clozapine for 20 days at various doses. Chronic haloperidol treatment significantly decreased hippocampal BDNF mRNA. The findings suggest that administration of atypical neuroleptics can prevent further neuronal deterioration in schizophrenia.

The article presents an abstract of a research paper analyzing the levels of DNA polymerases in aging rat brain cells. Isolated neurons and astroglia from cerebral cortex of inbred Wistar rats of three ages: 4 days, 6 months and 2 years, were suspended in extraction buffer and sonicated. From the results at all ages studied and in both types of brain cells, β polymerase appears to be the predominant one although other DNA-polymerases seem to be present in reasonable amounts.

The article presents an abstract of a research paper concerning the modulatory role of polyamines in nuclear transcription factor activator protein-1 (AP1) DNA binding in Murine brain. The addition of particular polyamines including spermine and spermidine markedly potentiated AP1 binding in nuclear extracts of whole murine brain. However, these polyamines were less potent in potentiating AP1 binding in the cerebellum obtained from mice injected with N-Methyl-D-aspartic acid and kainic acid.

The article presents an abstract of the research paper "Temperature Dependencies of Acetylcholinesterase Activity in Synaptosomal Membranes from Brain Cortex of Suslics Citellus Pigmaeus at Artificial Hypothermia and Hibernation." The study aimed at investigating adaptive changes in kinetic properties of acetylcholinesterase at hibernation.

The article presents an abstract of the research paper "Oxidative Stress in Oligodendroglia-Like Cells with Altered Phopholipid Composition." It will be presented in the joint meeting of the International Society for Neurochemistry and the European Society of Neurochemistry that will be held in Berlin, Germany from August 8-14, 1999. The most vulnerable tissue to oxidative damage is brain tissue. The high content of polyunsaturated fatty acids is one of the major reasons for this damage.

The article presents an abstract of the paper titled "Glutamate Transporters in Brain: New Complexities in Structure and Function." It discusses the mechanism of glutamate transport in the brain. The transport of glutamate is facilitated by the proteins of the family "excitatory amino acid transporters 1-5." The glutamate transporters mediate the coupled flux of glutamate functioning as a multi-subunit complex.

The article presents an abstract of the study "Lipid Signal Molecules and their Regulation During Oxidative Stress in the Developing Brain." The research paper for the study would be presented in the 30th Annual Meeting of the American Society for Neurochemistry, on March 14-17, 1999, in New Orleans, Louisiana.

The article presents an abstract of the paper "Human Brain Capillary Endothelium: ET-1-Induced Ca2+ Mobilization and F-Actin Cytoskeleton Is Modified by NO," by Y. Chen, R.M. McCarron, N. Azzam, F.A. Lenz and M. Siatz, which will be presented at the 30th Annual Meeting of the American Society for Neurochemistry to be held from March 14-17, 1999 in New Orleans, Louisiana. The study finds a functional relationship between NO and endothelin-1 (ET-1) at the level of the ET-1 receptor.