IMPACTS OF FOOD ON INTESTINAL FUNCTION & HEALTH - PowerPoint PPT Presentation

IMPACTS ¡OF ¡FOOD ¡ON ¡ ¡ INTESTINAL ¡FUNCTION ¡& ¡HEALTH ¡ JULIE ¡DALZIEL, ¡ SENIOR ¡RESEARCH ¡SCIENTIST, ¡ FOOD ¡NUTRITION ¡GENOMICS ¡ AGRI-­‑FOODS ¡& ¡HEALTH ¡ TOKYO, ¡12 ¡OCTOBER ¡2010 ¡

AGRESEARCH ¡  NZ’s largest Crown Research Institute • Wholly government-owned • 860 full-time equivalent staff (250 PhDs)  Research and development funding • 45% revenue from competitive grants • 55% revenue from commercial contracts • Total annual revenue (08/09): NZ$ 148m • Small amount of direct Government funding  Research and development scope • From “paddock to the plate” • Basic and applied research

OUR ¡FOCUS ¡  Raise productivity in the NZ pastoral sector in an environmentally sustainable manner.  Introduce a range of biotechnologies and other technologies to NZ.  Export our own biotechnologies and other technologies to the world.

AGRESEARCH ¡SITES: ¡ Ruakura ¡ (Hamilton) ¡  Grasslands ¡ (Palmerston ¡North) ¡ Wallaceville ¡ (Wellington) ¡   Lincoln ¡ (Christchurch) ¡  Invermay ¡ (Dunedin) ¡ AgResearch ¡Grasslands ¡  Palmerston ¡North ¡ + ¡several ¡farms ¡around ¡NZ ¡

AGRESEARCH ¡SCIENCE ¡STRUCTURE ¡ CEO Tom Richardson GM – Food & Textiles GM – Applied Biotechnologies GM – Agriculture & Environment Warren McNabb Jimmy Suttie Peter Benfell Biocontrol & Biosecurity Animal Improvement Agri-Foods & Health Agricultural Systems Animal Biosciences Rumen Nutrition & Bioinformatics, Climate, Land & Microbiology Mathematics & Statistics Environment Bio-based Products & Textiles Forage Improvement Animal Health Forage Biotechnology Greenhouse Gas Research Centre

NutriLon ¡ Meat ¡Science ¡ Food ¡Safety ¡ Chemistry ¡ Metabolism ¡ FuncLonal ¡(Epi) genomics ¡ PlaNorm ¡ Microbiology ¡ BioinformaLcs ¡ Proteomics ¡ MathemaLcs ¡ Metabolomics ¡ Modelling ¡ PlaNorm ¡ PlaNorm ¡ AgResearch’s Systems Food Nutrition Genomics Biology Platform Dairy Foods Food Microbiology & Safety Meat Science & Technology

DAIRY ¡FOODS ¡-­‑ ¡PROTEIN ¡PURIFICATION ¡  Purification of proteins and milk fractions • lab-scale (mg to gram quantities) • pilot-scale (gram to kg)  Anti-fungal, anti-viral, anti-bacterial e.g. nutraceutical food, crop protection, food preservative (Smolenski et al., 2007, J Proteome Res 6: 207-15)  Immune-modulating e.g. nutraceutical food  Enzymes for flavour development e.g. kokumi Mold growing on food and crop products

FOOD ¡NUTRITION ¡GENOMICS ¡TEAM ¡ Team Leader • Dr Nicole Roy Team composition • 12 scientists • 8 technicians • 11 PhD students Core capabilities • Functional genomics • Microbiology • Cell/tissue bioassays & electrophysiology • Animal models Core areas of research • Food, host and microbial interactions • Molecular Nutrition (nutritional genomics, epigenomics, metabolomics) • Neuromotor function and membrane physiology

The intestinal tract is a highly complex system – food/ microbe/mucosal interface >25,000 food components Human intestinal mucosa • Largest interface (barrier) between humans and the environment. • Critical for the balance between health and disease. Foods can affect: • Crucial to food utilisation; poor • probiotic bacterial growth function linked to diet-related • immune system balance diseases. • intestinal barrier function • intestinal motility

What is intestinal barrier function? Intestinal barrier separates intestinal lumen from underlying tissue and provides a protective interface between internal and external environment of body. Microbial ¡barrier ¡ (commensal ¡bacteria) ¡ Chemical ¡barrier ¡ (mucus ¡layer) ¡ Physical ¡barrier ¡ (the ¡epithelium) ¡ Immunological ¡ barrier ¡ (immune ¡cells ¡of ¡the ¡ lamina ¡propria) ¡ Muscle ¡layers ¡ ¡ (smooth ¡muscle ¡gut ¡wall) ¡ Hooper LV (2009) Nat Rev Microbiol. 7(5):367-74.

CELL ¡& ¡TISSUE ¡BIOASSAYS ¡ Techniques to measure changes in cell and tissue function in response to food/pharmaceuticals and therefore predict human health outcomes and detect unwanted gastrointestinal side effects.  Intestinal muscle assay  Fluorescence-based cellular assay  Intestinal permeability assay  Patch-clamping

NEUROMOTOR ¡FUNCTION ¡ Longitudinal Circular muscle muscle Interneuron motor neuron motor neuron ANAL ORAL Interneuron Network of neurons INTESTINAL ¡SMOOTH ¡MUSCLE ¡ Intestinal contraction is determined by circular and longitudinal muscle layers and affected by neuronal inputs

INTESTINAL ¡MUSCLE ¡ASSAY ¡  Measures effects of intestinal contents on smooth muscle contractility Control Test condition Contraction force Control Time  Provides information on whether intestinal contractility is affected.

FLUORESCENCE-BASED CELLULAR ASSAY ¡  Indirectly measure changes in membrane permeability by detecting changes in membrane potential or intracellular calcium.  Provides general information on whether receptor/ion channel mechanisms are affected  Permeability measured across the cell membrane (fluoresense, patch-clamp), apical between cells, or both (TEER). Cl K Cl K K K 3N 3N a a AT AT P P Na 2K Na 2K K K 2Cl 2Cl basolateral

TRANS-EPITHELIAL ELECTRICAL RESISTANCE ASSAY (TEER) ¡ bacteria  TEER measures changes in tight junction added resistance across an epithelial Caco-2 cell monolayer using an ohmmeter  Example shows a control, a bacterial strain that decreases epithelial resistance (strain 2), and another that increases resistance (strain 1). Control Strain 1 Strain 2  The results indicate improved (increased resistance) or weakened (decreased resistance) epithelial barrier function by bacteria (food ingredients could also be used).

ION ¡CHANNELS ¡IN ¡THE ¡CELL ¡MEMBRANE ¡ cellular permeability cellular excitability muscle contraction, neuronal ion and water firing and neurotransmitter absorption/secretion release faecal moisture intestinal motility faecal consistency (diarrhoea/constipation) - microbial balance - enteric nervous system - immune system

ELECTROPHYSIOLOGY ¡ Patch-clamping of cells to directly measure ionic currents across cell membranes as ion channels open and close. Express protein Identify cell Record current

ELECTROPHYSIOLOGY ¡ Patch-clamp data example of an inhibitory effect measured for a K+ ion channel control test condition recovery Dose response Provides specific information on how relationship receptor/ion channel mechanisms are affected. Dalziel et al . 2005, Toxicology Letters 155: 421-6.

RELEVANT ¡PUBLICATIONS ¡

COLLABORATORS ¡ NZ: Auckland University, Liggins (Auckland), Plant & Food Research, Otago University (Dunedin), Massey University Riddet Institute (Palmerston North). International: A/Prof Andrea Meredith, University of Maryland – K+ channel knockout mice Prof Shunyi Zhu, Chinese Academy of Sciences – K+ channel inhibitors Dr Yue-kun Ju, University of Sydney – Cardiac ion channels Prof Richard Aldrich, University of Texas – Ion channel research Prof Kikuji Itoh, Tokyo University – Germ-free rodents. Prof Jeremy Wells, Wageningen University – Intestinal barrier function. Prof Ian Rowland, Reading University – Molecular nutrition/cancer. Prof Jonathan Powell, Cambridge University – Nanoparticles.

COLLABORATIVE ¡OPPORTUNITIES ¡  Protein purification  Test effects of food ingredients on intestinal function, including motility and effects on receptors and ion channels  Explore underlying mechanisms of action We invite you to visit us in NZ! AgResearch ¡ Grasslands ¡ Palmerston ¡North ¡