Anti-ageing effects

Citation

(2009), "Anti-ageing effects", Nutrition & Food Science, Vol. 39 No. 3. https://doi.org/10.1108/nfs.2009.01739cab.008

Anti-ageing effects

Article Type: Food facts From: Nutrition & Food Science, Volume 39, Issue 3.

Soya shown to trigger the effect of calorie restriction

New research presented for the first time ever at the 9th National Nutrition & Health Conference in London on 21 November indicates that soya may mimic the body's natural biochemical trigger mechanism for calorie restriction.

It is well established that limiting calorie intake delays the onset of disease and prolongs healthy lifespan. Knowledge of the underlying mechanisms, and which dietary substances may mimic this effect, could result in public health benefits through the potential to provide anti-ageing effects and extended healthy lifespan. This research identified a possible mechanism by which limiting calorie intake may result in longer lifespan, thus identifying a potential target for anti-ageing intervention. The research also showed that daidzein, an isoflavone found in soya, may mimic some of these beneficial biochemical changes.

The academic behind this exciting research project, Laura Ions was awarded the Prestigious Alpro Foundation Award at an awards ceremony at the conference. The award of 2,500 Euros was presented to Laura by the President of the Foundation Professor Ian Rowlands, Professor of Human Nutrition, University of Reading. Laura's research has been chosen by the foundations scientific committee as the most outstanding research entry from across the UK and Ireland relating to plant-based nutrition with a special interest in soya.

This in vitro research tested the hypothesis that some of the beneficial effects of calorie restriction are mediated by an enzyme (Sirt1) through beneficial effects on DNA, and that this effect could be mimicked by isoflavones such as daidzein. Sirt1 belongs to a family of enzymes called sirtuins. Sirtuins are present in many organisms and have been implicated in the extension of lifespan due to calorie restriction. Sirtuins are thus potential targets for anti-ageing interventions or therapies. Sirt1 is involved in regulating fat metabolism, the production of glucose and insulin, and cell survival. It also mediates removal of the acetyl group (COCH3) from histone (protein within the chromosome), as part of gene regulation. Sirt1 activity is increased in situations of calorie restriction and Sirt1 promotes effects consistent with longevity.

DNA is hypomethylated with ageing and age-associated changes in DNA methylation can result in genome instability, inappropriate gene expression or gene silencing. DNA methylation is a potential mechanism to mediate effects of calorie restriction on lifespan.

The particular studies undertaken in the research project used the human intestinal cell line Caco-2. The cells were altered to over-express Sirt1 activity. DNA methylation was measured in the presence and absence of the soy isoflavones genistein and daidzein.

This study has established for the first time a beneficial effect of Sirt1 on DNA methylation. Other mechanisms by which Sirt1 may mediate extended lifespan with calorie restriction have already been proposed and this new finding represents an additional, or alternative pathway, particularly in the presence of daidzein (at supra physiological concentrations). Sirt1 over-expression and treatment with daidzein resulted in a statistically significant increase in DNA methylation (by 20 per cent; P > 0.05). The results were consistent with daidzein acting through Sirt1 to increase DNA methylation.

These exciting findings pave the way for further investigations to establish if Sirt1 helps to maintain the DNA methylation status of specific genes for which the ageing process has detrimental effects, and if Sirt1 has other effects that can be linked to lifespan extension. Further investigations are also needed to improve assay sensitivity, demonstrate the effect by alterative techniques, investigate physiological concentrations of daidzein and investigate whether the parent compound or a metabolite is responsible for the effect of daidzein.

About the National Nutrition & Health Conference

The National Nutrition & Health Conference was founded almost ten years ago by a group of health professionals who saw the need for more education dialogue and joined up thinking about nutrition and health across all health professionals. A focus is public health nutrition while a growing and significant proportion of effort is also given to the secondary care issues.

For more information about the conference visit www.nutritionandhealth.co.uk

About the Alpro Foundation

The Alpro Foundation is an independent non-profit organisation, which was founded in 1996. The objective of the foundation is to support and promote scientific knowledge and research in the field of nutrition and health with a focus on plant-based nutrition and a special interest in soya. The foundation aims to help increase the awareness and knowledge about the impact of “nutrition on human health” amongst health professionals and the general public.

The foundation establishes numerous activities to help achieve these objectives e.g. organising conferences, dissemination of an educational newsletter, awards for BSc and MSc and research grants.

For more information see www.alprofoundation.org