THE ROLE OF SIALIC ACID IN INFANT NUTRITION AND BRAIN DEVELOPMENT
Funder
National Health and Medical Research Council
Funding Amount
$402,750.00
Summary
Sub-optimal nutrition during critical periods of brain growth has persistent effects on the human brain. Premature infants are especially vulnerable because brain growth reaches its peak at 26 weeks gestation and remains high throughout the first year of life. Those fed human milk in the first month after birth have been shown to have a significant intellectual advantage compared with infants fed standard infant formulas. While the n-3 fatty acids such as DHA are thought to be important, other c ....Sub-optimal nutrition during critical periods of brain growth has persistent effects on the human brain. Premature infants are especially vulnerable because brain growth reaches its peak at 26 weeks gestation and remains high throughout the first year of life. Those fed human milk in the first month after birth have been shown to have a significant intellectual advantage compared with infants fed standard infant formulas. While the n-3 fatty acids such as DHA are thought to be important, other components of human milk may be of greater significance for brain growth. Our interest is in a sugar compound called sialic acid. It occurs in remarkably large amounts in human milk (up to 1g-L) but is present in only small quantities in infant formulas. Sialic acid is an important structural and functional component of brain cells. It is directly involved in nerve cell transmission, memory formation and cell-to-cell communication. During peak brain growth, young infants, especially pre-term ones, are unlikely to be able to synthesise sufficient sialic acid to meet their needs. At these times, they rely on human milk and infant formulas to supply the necessary building blocks. If their diet is a poor source of sialic acid, however, there may be lasting consequences for intellectual development. This research project addresses several questions. 1. Does oral sialic acid supplementation over the first few weeks of life increase both brain sialic acid levels as well as learning behaviour? 2. Is there any dose-response relationship - is more better? 3. Does supplementation influence the expression of genes encoding key enzymes in the brain? 4. Does dietary supplementation affect the activity of the liver enzyme involved in synthesis of sialic acid? If our findings can be extrapolated to human infants, they will have implications for the etiology of all types of cognitive and behavioural defects in children, including learning difficulties and attention deficit disorder.Read moreRead less
Relationship Between Anterior Cingulate Morphology, Neuronal Integrity And Function In Schizophrenia And OCD
Funder
National Health and Medical Research Council
Funding Amount
$312,813.00
Summary
Schizophrenia and obsessive-compulsive disorder (OCD) are extremely disabling psychiatric disorders. Both tend to appear in early adulthood and have a number of important similarities. These include problems with planning and organising thoughts, abnormal brain chemistry, and changed function in the same brain region, the anterior cingulate. The anterior cingulate has been known for some time to be involved in emotion, motivation and attention. However, it is now recognised as the interface betw ....Schizophrenia and obsessive-compulsive disorder (OCD) are extremely disabling psychiatric disorders. Both tend to appear in early adulthood and have a number of important similarities. These include problems with planning and organising thoughts, abnormal brain chemistry, and changed function in the same brain region, the anterior cingulate. The anterior cingulate has been known for some time to be involved in emotion, motivation and attention. However, it is now recognised as the interface between the emotional, feeling part of the brain and the controlling, thinking part. Many, if not all, of the functions performed by the anterior cingulate are disturbed in both schizophrenia and OCD, meaning that studying this region may provide important clues to the nature of the two illnesses. One important characteristic of the anterior cingulate which has not been considered in previous research is its division into three distinct subregions, each with their own specific function. In particular, there is a cognitive region, which deals with response selection and information processing, and an emotional region, which assesses motivational content and controls emotional learning. Because of the nature of the two disorders we intend to study, we believe that schizophrenia will be associated with more abnormalities of the cognitive region, while OCD will be associated with changes in the emotional region. Another important feature of our research design is that we intend to collect data from the same subjects using four separate brain imaging techniques, which provide information about different levels of brain structure and function. This will allow us to interpret our findings from measures of brain chemistry in the context of our findings of brain function. Hopefully this will help us to clarify the pathophysiology of schizophrenia and OCD, and provide potential ways to assess the effect of different treatment strategies in these illnesses.Read moreRead less
Neurodevelopmental Role Of Susceptibility Genes For Autism Spectrum Disorders: From Genes To Behaviour
Funder
National Health and Medical Research Council
Funding Amount
$482,968.00
Summary
Autism is a developmental neuropsychiatric syndrome characterised by impairments in three principal domains: social interaction, language and behavioural inflexibility. Autism spectrum disorder (ASD) refers to a group of neurodevelopmental syndromes with the common feature of dysfunctional reciprocal social interaction. In this project we will investigate the role of genes that increase the risk of ASD in the development of behaviours using an animal model. This work will lead to a better unders ....Autism is a developmental neuropsychiatric syndrome characterised by impairments in three principal domains: social interaction, language and behavioural inflexibility. Autism spectrum disorder (ASD) refers to a group of neurodevelopmental syndromes with the common feature of dysfunctional reciprocal social interaction. In this project we will investigate the role of genes that increase the risk of ASD in the development of behaviours using an animal model. This work will lead to a better understanding of the genetic basis of ASD.Read moreRead less
Promoting Plasticity And Functional Recovery In The Adult Brain: Enrichment And Transcranial Magnetic Stimulation
Funder
National Health and Medical Research Council
Funding Amount
$402,493.00
Summary
The adult human brain is unable to repair itself: axons do not regenerate effectively and there is limited reorganisation of remaining projections. Our research directly addresses how to form anatomically accurate and thus functionally useful networks through improving axonal regeneration per se, but more importantly it investigates clinically relevant, non-invasive methods that encourage the remaining nerve cells to reorganise, maximising the surviving resources of the damaged brain.
Regulation Of Pre-mRNA And MRNA Processing By The Neuron-specific Hu RNA-binding Proteins
Funder
National Health and Medical Research Council
Funding Amount
$477,750.00
Summary
The precise control of protein expression is absolutely critical in biology, and the key decisions about which genes are turned on or off at any one moment control the proper growth and maturation of an organism during development, and are responsible for the organism's homeostasis and proper response to environmental changes as an adult. Many gene expression programs are highly complex and controlled by regulating the activation of individual genes as they are copied from DNA to RNA. However, t ....The precise control of protein expression is absolutely critical in biology, and the key decisions about which genes are turned on or off at any one moment control the proper growth and maturation of an organism during development, and are responsible for the organism's homeostasis and proper response to environmental changes as an adult. Many gene expression programs are highly complex and controlled by regulating the activation of individual genes as they are copied from DNA to RNA. However, this activation is just the start of the process to produce an active protein. In higher organisms, these RNA copies almost always contain interruptions called introns, which must be excised from the RNA. Also, protein factors bound to specific RNAs can dictate whether the RNA is used to make protein or not, and these factors can also affect the localisation of the RNA to a specific sub-cellular destination, giving rise to highly localised protein expression. Evidence suggests that neurons are a cell type that rely heavily on mechanisms of RNA regulation. During development neurons become highly polarised, acquiring an axon which can elongate and find distant synaptic targets. While much is known about how axon growth cones respond to various guidance cues, the mechanisms by which the axon is able to translate this guidance cue information into structural changes which allow the growth cone to expand or collapse is largely unexplored. Recent evidence suggests that accurate growth cone guidance is absolutely dependent upon local protein synthesis. The functional corollary of this finding is that axon guidance requires RNA localisation and control of protein synthesis of RNAs in the growth cone. This phenomenon of spatial gene regulation within an individual cell is a central research interest for understanding how the brain functions.Read moreRead less
Using Contextual Effects To Test Theories Of Coding In Visual Cortex
Funder
National Health and Medical Research Council
Funding Amount
$200,500.00
Summary
The visual cortex is the main structure in the brain that processes the visual scene. Cells in the cortex respond selectively to features of the scene such as the orientation of objects, the direction they move and their brightness relative to the background. Cortical cells are arranged in a topographic map of visual space, so that nearby cells respond to light from nearby parts of the image. Recent advances have shown that cells talk to each other so a stimulus in one part of the visual field c ....The visual cortex is the main structure in the brain that processes the visual scene. Cells in the cortex respond selectively to features of the scene such as the orientation of objects, the direction they move and their brightness relative to the background. Cortical cells are arranged in a topographic map of visual space, so that nearby cells respond to light from nearby parts of the image. Recent advances have shown that cells talk to each other so a stimulus in one part of the visual field can influence the responses of cells looking at other regions. This communication between cells is important in guiding the brain to focus on areas of the visual scene that are most important, a process known as attention. An example would be that a mouse moving through the periphery of someone's vision would attract their attention away from objects elsewhere in the scene. This project is designed to study the way that cells in the visual cortex cooperate to guide attention. Attention is important because it reduces the need to process all the detail in the visual scene with the same level of accuracy, leaving more resources free to process what is important. Attention deficits are a problem for people with dyslexia, so understanding the physiological basis of attention is an important goal. As well as attention, the visual system has a range of other mechanisms to select important information from the visual scene. For example, visual adaptation tends to improve the ability to code changes in the visual scene at the expense of reducing the sensitivity of the system overall. This project will investigate the relationship between attentional and adaptive mechanisms in the visual cortex. We expect to establish the precise physiological mechanisms that drive adaptive and attentional mechanisms in the mammalian brain.Read moreRead less