Nutrition and Aging - Volume 1, issue 3-4

Authors: Alam, Iftikhar | Pawelec, Graham

Article Type: Research Article

Abstract: Demographic shifts worldwide are resulting in ever-increasing numbers of the elderly in both developed and developing countries. With aging come changes in physical and physiological integrity that are accompanied by a gradual decline in immunocompetence, commonly termed ‘immunosenescence’. Indeed, there are marked differences between young and old subjects with respect to the proportions of naïve and memory T cells and less marked differences in B cells and other immune cells. The number and proportion of late-stage memory T and B cells commonly increases, being particularly prominent in the CD8+ cytotoxic T cell pool. The accumulation of late-stage potentially “terminally” differentiated …CD8+CD27−CD28−CD45RA+ cells is often considered a hallmark of immunosenescence. Malnutrition in old age can further add to the severity of this age-associated remodeling of the immune system. Age-associated obesity, in particular, is accompanied by greater chronic inflammation, as reflected in increased plasma concentrations of C-reactive protein (CRP), IL-6, TNF and other factors which may mark compromised immunity. These physiological and immunological changes accompanying aging, markedly affected by nutritional status, are likely to be different in different parts of the globe. Data suggest a gradual decline in both nutritional status and immune functions with aging, but the details of these processes, and potential differences in different societies are unclear. In the following review, we will discuss the hallmarks of age-associated immune system changes and consider how these might be affected by nutritional status. Show more

Keywords: Aging, physical changes, nutrition, immunity, immunosenescence

DOI: 10.3233/NUA-130013

Citation: Nutrition and Aging, vol. 1, no. 3-4, pp. 151-165, 2012

Authors: Toward, Ruth E. | Walton, Gemma E. | Gibson, Glenn R.

Article Type: Research Article

Abstract: The global population is becoming increasingly older presenting medical and economic challenges to society. One factor associated with the aging process is immunosenescence, which may be defined as the decline in immunity with age, and represents a potential causative factor for many age related illnesses. The profile of the gut microbiota is also known to alter with aging and these changes have been linked the declines in the immunity observed in immunosenescence. For example, above the age of 60 years populations of bifidobacteria have been observed to decrease markedly, leading to a reduction in the inhibition of the growth of …some pathogens and potentially an increase in the susceptibility to infections. As such, an interest exists in attempting to reverse their decline in elderly individuals, through the use of both probiotics and prebiotics. Both approaches have shown to be encouraging in altering microbiota profiles beneficially and in reducing immunosenescence by reducing the colonisation potential of pathogens and counteracting chronic inflammation. The current review will give an overview of the process of immunosenescence and its role in disease, detail how the microbiota are involved in its progression and highlight data suggesting that pre- and probiotics may counteract these age-related events. Show more

Keywords: Age, gut, bacteria, bifidobacteria, fermentation, immunity, metabolism, probiotics, prebiotics

DOI: 10.3233/NUA-130014

Citation: Nutrition and Aging, vol. 1, no. 3-4, pp. 167-180, 2012

Authors: Jackson, Kim G. | Lovegrove, Julie A.

Article Type: Research Article

Abstract: Public health strategies for reducing the risk of coronary heart disease have focused on lowering plasma lipids, particularly cholesterol levels, with recent studies also highlighting triacylglycerol (TAG) as an important modifiable risk factor. One approach is to supplement the diet with probiotics, prebiotics or synbiotics. Probiotics are live microorganisms which when administered in adequate amounts confer a health benefit on the host. Putative health benefits include improved resistance to gastrointestinal infections, reduction in lipid levels and stimulation of the immune system. Prebiotics are selectively fermented dietary components that are aimed at improving host health through selective fermentation by the gut …microbiota, such as bifidobacteria and lactobacilli. Animal studies have shown prebiotics to markedly reduce circulating TAG and to a lesser extent cholesterol concentrations, with favourable but inconsistent findings with respect to changes in lipid levels in human studies. Here we provide an overview of the effects, and possible mechanisms, of probiotics, prebiotics and synbiotics (combination of a probiotic and prebiotic) on circulating lipeamia in humans. Show more

Keywords: Probiotics, prebiotics, synbiotics, coronary heart disease, lipids, lactic acid bacteria, short chain fatty acids, inulin

DOI: 10.3233/NUA-130017

Citation: Nutrition and Aging, vol. 1, no. 3-4, pp. 181-200, 2012

Authors: Guéroux, Marie | Laguerre, Michel | Szlosek-Pinaud, Magali | Fouquet, Eric | Pianet, Isabelle

Article Type: Research Article

Abstract: Tau that belongs to the family of microtubule-associated proteins is the major constituent of intraneuronal fibrillar lesions described in Alzheimer's Disease (AD). Its sequence homology with salivary proline-rich proteins (sPRP), known to fix tannins, combined with some epidemiological evidences that a moderate consumption of polyphenols presents benefits in AD, suggests that tannins can bind Tau protein and, perhaps, could inhibit or modulate the cascade of events leading to AD symptoms. To study the affinity of tannins towards the Tau proline rich domain P2, we have first synthesized a peptide representative of this domain, determined its 3D-structure and its affinity towards …different procyanidins (epicatechin-EC, epicatechin gallate-ECG, epigallocatechin gallate-EGCG and procyanidin B3 and B2) by using both NMR, molecular modelling and dynamic techniques. We have found that the Tau peptide is able to fix the different tested tannins in two distinct domains with an affinity in the mM range. Show more

Keywords: Alzheimer, Tau, procyanidins, interactions, NMR, molecular modelling

DOI: 10.3233/NUA-130015

Citation: Nutrition and Aging, vol. 1, no. 3-4, pp. 201-206, 2012

Authors: Giovannelli, Lisa

Article Type: Research Article

Abstract: Human studies indicate that consumption of olive oil is associated with decreased mortality, reduced cardiovascular risk and improved cognitive function in the elderly. Many of these benefits are thought to be due to the phenolic content of olive oil. In support of this, intervention studies in humans indicate that olive oil phenols protect blood lipids from oxidation and improve blood parameters of inflammation, hemostasis and vascular function, all risk factors for cardiovascular disease. The aim of this review is to evaluate the experimental evidence that olive oil phenols are beneficial to the aging process. Animal studies suggest that olive oil …phenols have preventive actions on age-related cognitive and motor dysfunction, an important cause of disability in the elderly. Supporting mechanistic in vitro studies indicate that olive oil phenols may inhibit inflammatory pathways and associated proteins, induce pathways related to cell protection and survival, and modulate pathways related to energy metabolism similar to anti-aging substances. Furthermore, they can interact with beta-amyloid peptide and Tau protein to inhibit the formation of protein aggregates, a hallmark of Alzheimer's disease. However, caution should be expressed in interpreting these in vitro data are as they are based on experiments carried out mainly using un-physiological concentrations of native olive phenols rather than phenolic metabolites. In conclusion, while in vivo data for the beneficial effects of olive oil phenols in aging are growing, a mechanistic explanation for these effects requires much additional research on the effects of metabolites at relevant concentrations. Show more

Keywords: Olive phenols, oxidative stress, inflammation, behavior, cell survival, energy metabolism

DOI: 10.3233/NUA-130016

Citation: Nutrition and Aging, vol. 1, no. 3-4, pp. 207-223, 2012

Article Type: Other

Citation: Nutrition and Aging, vol. 1, no. 3-4, pp. 225-226, 2012

Article Type: Other

Citation: Nutrition and Aging, vol. 1, no. 3-4, pp. 227-227, 2012