NUTRITION & IMMUNITY IN OLDER AGE

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1 NUTRITION & IMMUNITY IN OLDER AGE Parveen Yaqoob Professor of Nutritional Physiology Head of School, Chemistry, Food & Pharmacy Copyright University of Reading

2 SCOPE OF LECTURE Impact of ageing on the immune system What does EFSA say about nutrition and immunity? Introducing inflammaging as a concept Diet and inflammaging

3 Sources of variation Early life events Nutrient status Diet Gut flora Obesity Genetics Alcohol consumption Gender Immune function Smoking Age Hormonal status Exposure to pathogens (Infections) - Presence - History Vaccination history Exercise - Acute - Chronic Stress - Environmental - Physiological - Psychological

4 Ageing Bone marrow capacity to produce B cells Thymus involution Low naïve T cell output Sharp decline after 65y Naïve memory T cells Decreased capacity to fight new infections Oligoclonal expansion Dysfunctional cells fill immunological space Clinical implications Defective responses to infections, & vaccines

5 Appropriate nutrient supply Appropriate nutrient status Appropriate immune function

6 MALNUTRITION IN OLDER PEOPLE (From Stratton et al 2003; Disease-related malnutrition)

7 Contributes to normal function of the immune system Vitamin A Vitamin C Vitamin D Zinc Selenium and others. plays a role and supports normal function is acceptable, but stimulates or optimises normal function is not.

8 KEY CHALLENGES Impact of immunosenescence is intensified by nutritional deficiencies in older people. Impact of nutritional components on both immune response and clinical endpoints is controversial. Favourably modulating immune function does not necessarily translate into a corresponding change in clinical outcome.

9 DNA damage Oxidative stress Immunosenescence Obesity Inflamm- aging Years of exposure to inflammatory proteins Age-related chronic diseases Exacerbation of the ageing process Chronic renal failure Osteoarthritis Cognitive dysfunction Sarcopenia CVD Cancer

10 Inflammatory stimulus TNF-a IL-1b IL-6 Inflammation Loss of lean body mass Loss of bone mass Associated with dementia Insulin resistance Poor outcome from injury, surgery & trauma Loss of CD28 (immunosenescence)

11 PUTATIVE BIOMARKERS OF AGEING LIMITLESS Wagner POTENTIAL et al., 2016, LIMITLESS Nutrients, 8, 338 OPPORTUNITIES LIMITLESS IMPACT

12 INFLAMMATORY SCORE PREDICTS HOSPITALISATION AND DEATH 370 community dwelling persons aged > 65 years (mean age 74 years) Measured CRP, albumin, IL-6 (and cholesterol) gave a score for high CRP, low albumin, high IL-6, high cholesterol Follow-up 4 years 132 hospitalisations and 71 deaths Score predicted hospitalisation and death Salanitro et al. (2012) Arch. Gerontol. Geriatr. 54, e387-e391

13 INFLAMMAGING & SKELETAL MUSCLE PROTEIN: CAN PROTEIN INTAKE MAKE A DIFFERENCE? Draganidis (2016) J Nutr 146,

14 After the analysis, we conclude that there is sufficient evidence for an anti-inflammatory effects in aging only for n-3 PUFA intake, while the few existing intervention studies do not support a similar activity for vitamin D and whey supplements

15 Am J Clin Nutr (2011) 93,

16 Parallel, randomised 1-year trial in 1250 apparently healthy 65-80y olds. Dietary advice focussing on vitamin D, vitamin B12 and calcium. Primary outcome CRP.

17 SUMMARY Reduced resistance to infection and inflammageing are major challenges for an ageing population Inflammageing has metabolic consequences, including loss of muscle mass Inflammatory score appears to predict hospitalisation and death Lack of strong evidence that dietary protein provides bioactive peptides that stimulate muscle protein synthesis and mitigate against sarcopenia Evidence for other nutrients is also inconclusive