Sport Science at Nottingham Trent University

1. Getting to the guts of the matter - how changing the gut microbial population using diet may improve quality of life in a care home setting Dr Kirsty Hunter

2. Sport Science at Nottingham Trent University 2 01 August 2014

3. What causes ageing? • The two main theories of ageing are: • Programmed cell death – cell death is a genetically programmed event • Cellular wear and tear – ageing caused by an accumulation of cellular damage • Cell death is probably caused by a combination of both • Rate of ageing determined by genetics, environment, and lifestyle • Generally accepted that genes only account for 25% of the determinants of life length

4. What is ageing? • Ageing results from impaired immune, genetic, neurological, hormonal or antioxidant functions • These changes accumulate over time and are responsible for increased susceptibility to disease and death Number of cells and cellular function decreases Ability of organs to perform physiological functions decreases Increase in disease Increased risk of malnutrition e.g. PEM

5. So, can we influence the rate at which we age? • Yes, the ageing process is malleable – it may be possible to enhance the body’s natural mechanisms for protection and repair • Human lifespan may be extended by decreasing exposure to damage, or by enhancing repair, perhaps through improved nutrition, improved lifestyle and modified environment • Goals of successful ageing are: • To increase life expectancy • To increase the number of healthy years i.e. delay the onset of age-related diseases/disorders • Nutrition is an important factor in achieving both of these goals

6. How do physiological changes impact on nutritional status? Influence of ageing on nutritional status Appeal of food - reduction in sight, smell, taste Digestion and absorption Nutritional requirements Ability to obtain food

7. The causes and consequences of malnutrition are interlinked MALNUTRITION Decreased immune function Decreased nutrient intake Increased nutrient need Decreased muscle mass Increased use of medications Decreased accessibility and safety of food Increased illness

8. Poor nutrition can contribute to a number of health problems including: Constipation and other digestive disorders Anaemia Diabetes mellitus Muscle and bone disorders including osteoporosis, osteomalacia and osteoarthritis Overweight and obesity Cardiovascular diseases Declining mental health Changes to the nervous system and the immune system Cataract Some cancers e.g. breast, prostate Nutrition has a significant impact on ageing

9. Another component of the body which changes are the microorganisms which live in the gut

10. The Gastrointestinal Tract • In our bodies there are 20 x more bacteria than human cells • We carry around 1kg of bacteria • Gut problems take up significant GP time

11. Gut microfloral profile

13. Distribution of bacteria on the gut wall

14. Factors affecting colonisation and growth of bacteria in the gut Physicochemical • Amount and type of substrate • pH of gut contents • Redox potential Microbial • Competition • Inhibition through end products • Specific inhibitor substances • Bile salts • Immunity

17. Metabolic Fate of Principal Carbohydrate End Products • Acetate: metabolised in muscle, kidney, heart, brain • Propionate: cleared by the liver • Butyrate: metabolised by the colonic epithelium, regulates cell growth • Lactate, ethanol, pyruvate: absorbed, electron sink products • Hydrogen: partially excreted in breath, metabolised by bacteria

18. Metabolic Fate of Principal Protein End Products • Ammonia: formed by deamination of amino acids, detoxified by urea formation in the liver, induces quick cell turnover • Phenols/indoles: produced from aromatic amino acids, may act as co-carcinogens • Amines: formed by decarboxylation of amino acids,linked to migraine, cancer, schizophrenia

19. Different bacteria use different substances as food and generate different end products Different bacteria have different effects on body functions Different bacteria have different effects on disease

21. 2 Inhibition of growth of exogenous and harmful bacteria Ps. aeruginosa Intestinal putrefaction Proteus sp. Candida sp. Digestion/ absorption of food ingredients & minerals Sulphate reducers Clostridia Enterococci Production of carcinogens Stimulate immune function E. coli Lactobacilli Streptococci Diarrhoea, constipation, infections, liver damage, cancer, toxigenesis, encephalopathy Vitamin synthesis Bifidobacteria Bacteroides 11 No./g faeces (log scale)

22. Gut Disorders • Acute inflammation • Diverticulitis • Inflammatory bowel disease • Bowel cancer • Constipation • Food poisoning • IBS • Systemic????

23. Balanced gut flora Dysbiosis

24. Age related changes in gut microflora are caused by: • Greater permeability of the gut wall • Reduced transit times • Secretion of acids by the stomach lining • Reduced numbers of beneficial bacteria • Bifidobacteria, Eubacterium • Increased numbers of putrefactive bacteria • Clostridia, Enterobacteria What kind of changes occur?

25. Could the microbial organisms that live in the gut impact on quality of life and disease in the elderly? Can we beneficially change the types of gut microorganisms using food and drink?

26. Influencing the ‘Balance’ PROBIOTICS A live microbial feed supplement which beneficially affects the host Examples: lactobacilli, bifidobacteria

27. Commercially available probiotics • Bio yoghurts • Fermented milks • Fortified fruit juice Fairly short shelf life Need refrigeration Debate on numbers of live organisms • Powders • Capsules • Tablets • Sprays Longer shelf life Storage easy Labels often misleading

28. The Alternative Approach PREBIOTICS ‘Non digestible food ingredients that selectively stimulate a limited number of bacteria in the colon, to improve host health’ • (after Gibson and Roberfroid, 1995) • Market leaders are the fructo-oligosacharides, galacto-oligosaccharides & the polysaccharide inulin

29. Prebiotics 1. Must be stable under acidic conditions and small gut secretions 3. Must be selectively metabolised 2. Must get to the colon intact

30. Vehicles for Prebiotics • Beverages and fermented milks • Health drinks, spreads • Cereals • Biscuits* • Confectionery, cakes • Food supplements

31. Issues with probiotics • Species variability • Viability in the product • Contradictory results Why prebiotics may be better • Heat stable • Increases the host’s own gut microbial population • Not a living product so no issues of viability

32. 22 elderly subjects fed prebiotic powder for 10 weeks • Increased numbers of Bifidobacterium spp., Lactobacillus spp, Enterococcus spp in faeces • Lower numbers of Bacteroides spp, Clostridium spp, E. coli, Desulfovibrio spp. Vulevic, 2008

33. Effects on markers of immune status

34. Synbiotics Müller® Vitality® Apple & Prune 150g Ingredients Yogurt, Sugar, Fruit (Apples (6%), Water, Prune Puree (4%), Inulin, Modified Maize Starch, Flavourings, Omega 3 from Refined Fish Oil, Acidity Regulators: Citric Acid, Sodium Citrates; Cultures: Sugar, Bifidobacterium sp., Lactobacillus acidophilus Nutritional Values per 100g

35. 2 Inhibition of growth of exogenous and harmful bacteria Ps. aeruginosa Intestinal putrefaction Proteus sp. Candida sp. Digestion/ absorption of food ingredients & minerals Sulphate reducers Clostridia Enterococci Production of carcinogens Stimulate immune function E. coli Lactobacilli Streptococci Diarrhoea, constipation, infections, liver damage, cancer, toxigenesis, encephalopathy Vitamin synthesis Bifidobacteria Bacteroides 11 No./g faeces (log scale)

36. Potential uses of pro- & prebiotics in the elderly

37. Why are pro- and prebiotics an attractive proposal for use in residential care? • Can be incorporated into food (commercially available or cooked on site) • Virtually tasteless • Prebiotics are heat stable • Food ingredients not drugs • Few side effects • Many potential beneficial effects

38. What do we need to do? • Free-living versus residential care • Measure absence/presence of disease and functional markers • Quality of life markers • Nutritional status

39. Thank you for listening