Glutathione and glutathione-dependent enzymes: From biochemistry to gerontology and successful aging

The tripeptide glutathione (GSH), namely γ-L-glutamyl-L-cysteinyl-glycine, is an ubiquitous low-molecular weight thiol nucleophile and reductant of utmost importance, representing the central redox agent of most aerobic organisms. GSH has vital functions involving also antioxidant protection, detoxification, redox homeostasis, cell signaling, iron metabolism/homeostasis, DNA synthesis, gene expression, cysteine/protein metabolism, and cell proliferation/differentiation or death including apoptosis and ferroptosis. Various functions of GSH are exerted in concert with GSH-dependent enzymes. Indeed, although GSH has direct scavenging antioxidant effects, its antioxidant function is substantially accomplished by glutathione peroxidase-catalyzed reactions with reductive removal of H2O2, organic peroxides such as lipid hydroperoxides, and peroxynitrite; to this antioxidant activity also contribute peroxiredoxins, enzymes further involved in redox signaling and chaperone activity. Moreover, the detoxifying function of GSH is basically exerted in conjunction with glutathione transferases, which have also antioxidant properties. GSH is synthesized in the cytosol by the ATP-dependent enzymes glutamate cysteine ligase (GCL), which catalyzes ligation of cysteine and glutamate forming γ-glutamylcysteine (γ-GC), and glutathione synthase, which adds glycine to γ-GC resulting in GSH formation; GCL is rate-limiting for GSH synthesis, as is the precursor amino acid cysteine, which may be supplemented as N-acetylcysteine (NAC), a therapeutically available compound. After its cell export, GSH is degraded extracellularly by the membrane-anchored ectoenzyme γ-glutamyl transferase, a process occurring, as GSH synthesis and export, in the γ-glutamyl cycle. GSH degradation occurs also intracellularly by the cytoplasmic enzymatic ChaC family of γ-glutamyl cyclotransferase. Synthesis and degradation of GSH, together with its export, translocation to cell organelles, utilization for multiple essential functions, and regeneration from glutathione disulfide by glutathione reductase, are relevant to GSH homeostasis and metabolism. Notably, GSH levels decline during aging, an alteration generally related to impaired GSH biosynthesis and leading to cell dysfunction. However, there is evidence of enhanced GSH levels in elderly subjects with excellent physical and mental health status, suggesting that heightened GSH may be a marker and even a causative factor of increased healthspan and lifespan. Such aspects, and much more including GSH-boosting substances administrable to humans, are considered in this state-of-the-art review, which deals with GSH and GSH-dependent enzymes from biochemistry to gerontology, focusing attention also on lifespan/healthspan extension and successful aging; the significance of GSH levels in aging is considered also in relation to therapeutic possibilities and supplementation strategies, based on the use of various compounds including NAC-glycine, aimed at increasing GSH and related defenses to improve health status and counteract aging processes in humans.

The roles of NADPH and isocitrate dehydrogenase in cochlear mitochondrial antioxidant defense and aging

Hearing loss is the third most prevalent chronic health condition affecting older adults. Age-related hearing loss affects one in three adults over 65 years of age and is caused by both extrinsic and intrinsic factors, including genetics, aging, and exposure to noise and toxins. All cells possess antioxidant defense systems that play an important role in protecting cells against these factors. Reduced nicotinamide adenine dinucleotide phosphate (NADPH) serves as a co-factor for antioxidant enzymes such as glutathione reductase and thioredoxin reductase and is produced by glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, isocitrate dehydrogenase 1 (IDH1) or malic enzyme 1 in the cytosol, while in the mitochondria, NADPH is generated from mitochondrial transhydrogenase, glutamate dehydrogenase, malic enzyme 3 or IDH2. There are three isoforms of IDH: cytosolic IDH1, and mitochondrial IDH2 and IDH3. Of these, IDH2 is thought to be the major supplier of NADPH to the mitochondrial antioxidant defense system. The NADP⁺/NADPH and NAD⁺/NADH couples are essential for maintaining a large array of biological processes, including cellular redox state, and energy metabolism, mitochondrial function. A growing body of evidence indicates that mitochondrial dysfunction contributes to age-related structural or functional changes of cochlear sensory hair cells and neurons, leading to hearing impairments. In this review, we describe the current understanding of the roles of NADPH and IDHs in cochlear mitochondrial antioxidant defense and aging.

Redox Parameters as Markers of the Rate of Aging and Predictors of Life Span

Oxidative stress has been reported to increase with aging, and although several age-related changes in redox parameters have been described, none of them have been verified as markers of the rate of aging and life span. Therefore, antioxidant (catalase, glutathione peroxidase, reductase activities, and reduced glutathione) and oxidant (oxidized glutathione, basal superoxide anion, and malondialdehyde concentrations) parameters were studied in whole blood cells from humans divided into different age groups (adult, mature, older adult, nonagenarian, and centenarian) in a cross-sectional study. Moreover, the same parameters were investigated in peritoneal leukocytes of mice at the analogous human ages (adult, mature, old, very old, and long-lived) in a longitudinal study as well as in adult prematurely aging mice. The results reveal that the age-related alterations of these markers are similar in humans and mice, with decreased antioxidants and increased oxidants in old participants, whereas long-lived individuals show similar values to those in adults. In addition, adult prematurely aging mice showed similar values to those in chronologically old mice and had a shorter life span than nonprematurely aging mice. Thus, these parameters could be proposed as markers of the rate of aging and used to ascertain biological age in humans.

Selenium Status in Elderly People: Longevity and Age-Related Diseases

BACKGROUND

Selenium (Se) is a trace element active in selenoproteins, which can regulate oxidative stress. It is generally perceived as an import factor for maintaining health in the elderly.

METHODS

The goal of this review is to discuss selenium concentration in biological samples, primarily serum or plasma, as a function of age and its relation with longevity. The elemental level in various age-related diseases is reviewed.

CONCLUSION

Highest selenium values were observed in healthy adults, while in an elderly population significantly lower concentrations were reported. Variables responsible for contradictory findings are mentioned. Risk and benefits of Se-supplementation still remain under debate.

Riboflavin - properties, occurrence and its use in medicine

Riboflavin is built on an isoalloxazin ring, which contains three sixcarbon rings: benzoic, pyrazine and pyrimidine. Riboflavin is synthesized by some bacteria, but among humans and animals, the only source of flavin coenzymes (FAD, FMN) is exogenous riboflavin. Riboflavin transport in enterocytes takes place via three translocators encoded by the SLC52 gene. Deficiency of dietary riboflavin has wide ranging implications for the efficacy of other vitamins, the mechanism of cellular respiration, lactic acid metabolism, hemoglobin, nucleotides and amino acid synthesis. In studies it was found that, pharmacologic daily doses (100 mg) have the potential to react with light, which can have adverse cellular effects. Extrene caution should be exercised when using riboflavin as phototherapy in premature newborns. At the cellular level, riboflavin deficiency leads to increased oxidative stress and causes disorders in the glutathione recycling process. Risk factors for developing riboflavin deficinecy include pregnancy, malnutrition (including anorexia and other eating disorders, vegitarianism, veganism and alcoholism. Furthermore, elderly people and atheletes are also at risk of developing this deficiency. Widespread use of riboflavin in medicine, cancer therapy, treatment of neurodegenerative diseases, corneal ectasia and viral infections has resulted in the recent increased interest in this flavina.

Relation of Moderate Physical Activity to Blood Markers of Oxidative Stress and Antioxidant Defense in the Elderly

The aim of the present study was to establish whether markers of oxidative stress and the enzymatic defense system of the blood are related to moderate physical activity in younger old and the oldest old men. They were divided into four groups according to the age and level of physical activity (groups YN and YA—inactive and active younger old men aged 65-74 years, groups ON and OA—inactive and active oldest old men aged 90-99 years). Venous blood was collected from the subjects in the morning before breakfast. MDA concentration and antioxidant enzyme activities (SOD, CAT, GPx, and GR) in erythrocyte hemolysates were assayed. The concentration of isoprostanes (8-iso-PGF2α) and carbonyl groups in protein (CP) was measured in plasma and serum. All assayed antioxidant enzyme activities and the SOD/GPx ratios were significantly higher in the active younger old males than in all the inactive ones. In the group of oldest old active participants, only the GPx activity was significantly higher compared to the inactive oldest old males. The activity of CAT and GPx in the younger old inactive men was significantly lower than that in the oldest old inactive subjects. However, SOD, CAT, and GR activities and SOD/GPx ratio were significantly higher in the younger old active men compared to the oldest old active participants. The concentrations of isoprostanes, protein carbonyls, and MDA were significantly lower in both active and inactive younger old males than in the respective groups of the oldest old men and in both groups of active men, independently of age, compared to the respective inactive subjects. The present study confirmed that oxidative stress is related to age. Physical activity caused a decrease of oxidative stress markers independently of age and resulted in an increase of GPx activity in both younger old and the oldest old active groups.

Metabolic Slowing and Reduced Oxidative Damage with Sustained Caloric Restriction Support the Rate of Living and Oxidative Damage Theories of Aging

Calorie restriction (CR) is a dietary intervention with potential benefits for healthspan improvement and lifespan extension. In 53 (34 CR and 19 control) non-obese adults, we tested the hypothesis that energy expenditure (EE) and its endocrine mediators are reduced with a CR diet over 2 years. Approximately 15% CR was achieved over 2 years, resulting in an average 8.7 kg weight loss, whereas controls gained 1.8 kg. In the CR group, EE measured over 24 hr or during sleep was approximately 80-120 kcal/day lower than expected on the basis of weight loss, indicating sustained metabolic adaptation over 2 years. This metabolic adaptation was accompanied by significantly reduced thyroid axis activity and reactive oxygen species (F2-isoprostane) production. Findings from this 2-year CR trial in healthy, non-obese humans provide new evidence of persistent metabolic slowing accompanied by reduced oxidative stress, which supports the rate of living and oxidative damage theories of mammalian aging.

The Effect of Moderate- Versus High-Intensity Resistance Training on Systemic Redox State and DNA Damage in Healthy Older Women

This study investigated effects of a 16-week progressive resistance training program (RTP) with elastic bands at two different intensities on systemic redox state, DNA damage, and physical function in healthy older women.

Methods:

Participants were randomly assigned to the high-intensity group (HIGH; n = 39), moderate-intensity group (MOD; n = 31), or control group (CG; n = 23). The exercise groups performed an RTP twice a week with three to four sets of 6 (HIGH) or 15 (MOD) repetitions of six overall body exercises at a perceived exertion rate of 8–9 on the OMNI-Resistance Exercise Scale for use with elastic bands. Thiol redox state was determined by reduced glutathione (GSH), oxidized glutathione (GSSG), and GSSG/GSH in blood mononuclear cells. Degree of DNA damage was assessed by presence of the oxidized DNA base molecule 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-OHdG) in urine. Physical function monitoring was based on the arm curl, chair stand, up and go, and 6-min walk tests.

Results:

The HIGH group showed a significant increase in 8-OHdG (+71.07%, effect size [ES] = 1.12) and a significant decrease in GSH (−10.91, ES = −0.69), while the MOD group showed a significant decrease in 8-OHdG levels (−25.66%, ES = −0.69) with no changes in thiol redox state. GSH levels differed significantly between the HIGH and CG groups posttest. The exercise groups showed significant improvements in physical function with no differences between groups.

Conclusion:

RTP at a moderate rather than high intensity may be a better strategy to reduce DNA damage in healthy older women while also increasing independence.

Vitamin E family: Role in the pathogenesis and treatment of Alzheimer's disease

Introduction

Vitamin E family, composed by tocopherols and tocotrienols, is a group of compounds with neuroprotective properties. The exact role in the pathogenesis and the benefit of vitamin E as treatment for Alzheimer's disease (AD) are still under debate.

Methods

A literature search in PubMed, Medline, and Cochrane databases has been carried out. All types of studies, from bench and animal models to clinical, were included.

Results

High plasma vitamin E levels are associated with better cognitive performance, even if clear evidence of their ability to prevent or delay cognitive decline in AD is still lacking. Each vitamin E form is functionally unique and shows specific biological functions. Tocotrienols seem to have superior antioxidant and anti-inflammatory properties compared with tocopherols.

Discussion

The benefit of vitamin E as a treatment for AD is still under debate, mainly because of the inconsistent findings from observational studies and the methodological limitations of clinical trials.

Vitamin E Supplementation Delays Cellular Senescence In Vitro

Vitamin E is an important antioxidant that protects cells from oxidative stress-induced damage, which is an important contributor to the progression of ageing. Ageing can be studied in vitro using primary cells reaching a state of irreversible growth arrest called senescence after a limited number of cellular divisions. Generally, the most utilized biomarker of senescence is represented by the expression of the senescence associated β-galactosidase (SA-β-gal). We aimed here to study the possible effects of vitamin E supplementation in two different human primary cell types (HUVECs and fibroblasts) during the progression of cellular senescence. Utilizing an unbiased automated system, based on the detection of the SA-β-gal, we quantified cellular senescence in vitro and showed that vitamin E supplementation reduced the numbers of senescent cells during progression of ageing. Acute vitamin E supplementation did not affect cellular proliferation, whereas it was decreased after chronic treatment. Mechanistically, we show that vitamin E supplementation acts through downregulation of the expression of the cycline dependent kinase inhibitor P21. The data obtained from this study support the antiageing properties of vitamin E and identify possible mechanisms of action that warrant further investigation.

Effects of vitamin E on cognitive performance during ageing and in Alzheimer's disease

Vitamin E is an important antioxidant that primarily protects cells from damage associated with oxidative stress caused by free radicals. The brain is highly susceptible to oxidative stress, which increases during ageing and is considered a major contributor to neurodegeneration. High plasma vitamin E levels were repeatedly associated with better cognitive performance. Due to its antioxidant properties, the ability of vitamin E to prevent or delay cognitive decline has been tested in clinical trials in both ageing population and Alzheimer’s disease (AD) patients. The difficulty in performing precise and uniform human studies is mostly responsible for the inconsistent outcomes reported in the literature. Therefore, the benefit of vitamin E as a treatment for neurodegenerative disorders is still under debate. In this review, we focus on those studies that mostly have contributed to clarifying the exclusive function of vitamin E in relation to brain ageing and AD.

Maintaining good hearing: calorie restriction, Sirt3, and glutathione

Reducing calorie intake extends the lifespan of a variety of experimental models and delays progression of age-related hearing loss (AHL). AHL is a common feature of aging and is characterized by age-related decline of hearing associated with loss of sensory hair cells, spiral ganglion neurons, and/or stria vascularis degeneration in the cochlea. Sirtuins are a family of NAD(+)-dependent enzymes that regulate lifespan in lower organisms and have emerged as broad regulators of cellular fate. Our recent study indicated that mitochondrial Sirt3, a member of the sirtuin family, mediates the anti-aging effects of calorie restriction (CR) on AHL in mice. Interestingly, we also found that weight loss alone may not be sufficient for maintaining normal hearing. How does CR slow the progression of AHL through regulation of Sirt3? Here we review the evidence that during CR, Sirt3 slows the progression of AHL by promoting the glutathione-mediated mitochondrial antioxidant defense system in mice. A significant reduction in food consumption in one's daily life may not be a desirable and realistic option for most people. Therefore, identification/discovery of compounds that induce the activation of SIRT3 or glutathione reductase, or that increase mitochondrial glutathione levels has potential for maintaining good hearing through mimicking the anti-aging effects of CR in human inner ear cells.

Markers of oxidative stress and erythrocyte antioxidant enzyme activity in older men and women with differing physical activity

The aim of the present study was to examine the relationship between markers of oxidative stress and erythrocyte antioxidant enzyme activity and physical activity in older men and women. The present study included 481 participants (233 men and 248 women) in the age group 65-69 years (127 men and 125 women) and in the age group 90 years and over (106 men and 123 women). The classification of respondents by physical activity was based on answers to the question if, in the past 12 months, they engaged in any pastimes which require physical activity. The systemic oxidative stress status was assessed by measuring plasma iso-PGF2α and protein carbonyl concentration as well as erythrocyte antioxidant enzymes activity, i.e., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR). The concentration of plasma iso-PGF2α and protein carbonyls (CP) was lower in groups of younger men and women compared to the respective older groups. In all examined groups, physical activity resulted in decrease of these oxidative stress markers and simultaneously caused adaptive increase in the erythrocyte SOD activity. Additionally, in active younger men CAT, GPx, and GR activities were higher than in sedentary ones. In conclusion, oxidative stress increase is age-related, but physical activity can reduce oxidative stress markers and induce adaptive increase in the erythrocyte antioxidant enzyme activity, especially SOD, even in old and very old men and women.

Mouse models of age-related mitochondrial neurosensory hearing loss

Hearing loss is the most common sensory disorder in the elderly population. Overall, 10% of the population has a hearing loss in the US, and this age-related hearing disorder is projected to afflict more than 28 million Americans by 2030. Age-related hearing loss is associated with loss of sensory hair cells (sensory hearing loss) and/or spiral ganglion neurons (neuronal hearing loss) in the cochlea of the inner ear. Many lines of evidence indicate that oxidative stress and associated mitochondrial dysfunction play a central role in age-related neurodegenerative diseases and are a cause of age-related neurosensory hearing loss. Yet, the molecular mechanisms of how oxidative stress and/or mitochondrial dysfunction lead to hearing loss during aging remain unclear, and currently there is no treatment for this age-dependent disorder. Several mouse models of aging and age-related diseases have been linked to age-related mitochondrial neurosensory hearing loss. Evaluation of these animal models has offered basic knowledge of the mechanism underlying hearing loss associated with oxidative stress, mitochondrial dysfunction, and aging. Here we review the evidence that specific mutations in the mitochondrial DNA or nuclear DNA that affect mitochondrial function result in increased oxidative damage and associated loss of sensory hair cells and/or spiral ganglion neurons in the cochlea during aging, thereby causing hearing loss in these mouse models. Future studies comparing these models will provide further insight into fundamental knowledge about the disordered process of hearing and treatments to improve the lives of individuals with communication disorders. This article is part of a Special Issue entitled 'Mitochondrial function and dysfunction in neurodegeneration'.

Oxidative stress and longevity in okinawa: an investigation of blood lipid peroxidation and tocopherol in okinawan centenarians

Background. The Free Radical Theory of Aging mechanistically links oxidative stress to aging. Okinawa has among the world's longest-lived populations but oxidative stress in this population has not been well characterized. Methods. We compared plasma lipid peroxide (LPO) and vitamin E—plasma and intracellular tocopherol levels (total α, β, and γ), in centenarians with younger controls. Results. Both LPO and vitamin E tocopherols were lower in centenarians, with the exception of intracellular β-tocopherol, which was significantly higher in centenarians versus younger controls. There were no significant differences between age groups for tocopherol: cholesterol and tocopherol: LPO ratios. Correlations were found between α-Tocopherol and LPO in septuagenarians but not in centenarians. Conclusions. The low plasma level of LPO in Okinawan centenarians, compared to younger controls, argues for protection against oxidative stress in the centenarian population and is consistent with the predictions of the Free Radical Theory of Aging. However, the present work does not strongly support a role for vitamin E in this phenomenon. The role of intracellular β-tocopherol deserves additional study. More research is needed on the contribution of oxidative stress and antioxidants to human longevity.

Effect of riboflavin supply on student body's provision in north-western Poland with riboflavin measured by activity of glutathione reductase considering daily intake of other nutrients

The riboflavin nutritional status of 120 people, age 22-25, studying in Szczecin, Poland, together with contents of their daily food servings were studied. Body's provision with riboflavin was determined using the erythrocyte glutathione reductase activity coefficient (EGRAC) and was compared with a sample in which the enzyme activity was stimulated with flavin adenine dinucleotide. The information concerning diets was collected with the method of a 7-day food record prior to blood collection. Biochemical deficiency in riboflavin was observed in 33.7% of women and 25% of men. The resulting average EGRAC value was 1.02 for women and 0.88 for men. Assessment of significant differences in riboflavin provision between the sexes revealed better provision in the male group. The comparison of EGRAC values with riboflavin content in 7-day diets of the respondents showed that the average intake of this vitamin in the female group, in which biochemical deficiency was observed, amounted to 1.05 mg, whereas in the male group it was, on average, 1.39 mg. In the group of people in which the potential risk of riboflavin deficiency in the body was not observed, the level of this vitamin consumption was, on average, 1.43 mg and 1.8 mg in the female and male groups, respectively. Women with biochemical riboflavin deficiency consumed significantly less of all the analyzed nutrients in comparison with the people without riboflavin deficiency.

Response of oxidative stress markers and antioxidant parameters to an 8-week aerobic physical activity program in healthy, postmenopausal women

The aim of the study was to assess the influence of an 8-week aerobic physical activity program on oxidative stress markers, antioxidant parameters, and selected metabolic parameters in healthy, postmenopausal women. The study was carried out in a group of 41 healthy women (mean age 65 years) participating in an 8-week cycle ergometer physical workout of moderate intensity. Before and after completing the training program, the following parameters were assessed: total antioxidant status (TAS) and concentrations of thiobarbituric acid reactive substances (TBARS) in plasma, serum levels of antibodies against oxidatively modified low-density lipoproteins (LDL) (oLAB), serum concentrations of glucose, high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), insulin, and reduced glutathione (GSH) concentrations in red blood cells (RBC). Atherogenic index of plasma (AIP) and insulin resistance index (HOMA(IR)) were calculated. The 8-week aerobic physical activity program resulted in significant decrease (p<0.01) in serum glucose and LDL-cholesterol (LDL-C) levels, plasma TBARS concentrations (p<0.05), and in significant decrease of HOMA(IR) (p<0.01). TAS of plasma and GSH concentrations in RBC increased significantly (p<0.01) over the study period. The results show that an 8-week aerobic training enhanced insulin sensitivity, and improved the balance between oxidants and antioxidants in healthy, postmenopausal women.

Aging, resting metabolic rate, and oxidative damage: results from the Louisiana Healthy Aging Study

BACKGROUND

The aging process occurs at variable rates both among and within species and may be related to the variability in oxygen consumption and free radical production impacting oxidative stress. The current study was designed to test whether nonagenarians have a relatively low metabolic rate and whether it is associated with low levels of oxidative stress relative to age.

METHODS

Resting metabolic rate (RMR) and markers of oxidative stress to lipids, proteins, and DNA were measured in three groups of individuals aged 20-34 (n=47), 60-74 (n=49), and>or=90 years (n=74).

RESULTS

RMR, adjusted for fat-free mass, fat mass, and sex, was lower in both older groups when compared to the young group (p<or=.0001). There were no significant differences in urinary isoprostanes, serum protein carbonyls, or DNA fragmentation between groups, and RMR was not related to any markers of oxidative stress.

CONCLUSIONS

This study confirms an age-related decline in RMR independent of changes in body composition but surprisingly did not show an accumulation of oxidative damage with increasing age. Our data challenge the theory that RMR is a significant determinant of oxidative stress and therefore contributes to the aging process.

Insulin resistance, oxidative stress markers and the blood antioxidant system in overweight elderly men

The purpose of the study was to examine in the blood of overweight men aged from 62 to 83 years, the relationships between age and insulin resistance, selected parameters of the oxidative stress, and the antioxidant defense system. The population studied was divided into two groups: the group 'young-old' consisted of men aged 62 to 74 years old, and the group 'old-old'--of men aged between 75 and 83 years. The total antioxidative status (TAS) and concentrations of thiobarbituric acid reactive substances (TBARS) were measured in the blood plasma. In the serum samples, the levels of antibodies against oxidized LDL (oLAB), glucose, total cholesterol, HDL-cholesterol, triglycerides and insulin were measured. Homeostasis Model Assessment of Insulin Resistance (HOMAIR) was calculated. Concentration of reduced glutathione (GSH) and glutathione peroxidase activity (GPx) were determined in the red blood cells hemolysate. The results of the study did not show significant differences between groups investigated with respect to concentrations of TBARS, TAS, GSH and GPx. However, significantly higher concentrations of glucose and antibodies against oxLDL (p < 0.05) were observed in the group of men over 74 years old in comparison to the group of 'young-old' men. It was indicated that the increased insulin resistance and hyperglycemia in elderly men are related to body mass and that they cause intensified oxidative modifications of LDL.

Position paper of the American Dietetic Association: Nutrition across the spectrum of aging

It is the position of the American Dietetic Association that older Americans receive appropriate care; have broadened access to coordinated, comprehensive food and nutrition services; and receive the benefits of ongoing research to identify the most effective food and nutrition programs, interventions, and therapies across the spectrum of aging. Food and water and nutritional well-being are essential to the health, self-sufficiency, and quality of life for the fast growing, heterogeneous, multiracial, and ethnic populations of older adults. Many people, as they age, remain fully independent and actively engaged in their communities; however, others fare less well and need more support. A broad array of appropriate, culturally sensitive food and nutrition services, physical activities, and health and supportive care customized to the population of older adults are necessary. National, state, and local policies that promote coordination and integration of food and nutrition services into health and supportive systems are needed to maintain independence, functional ability, chronic disease management, and quality of life. Dietetics professionals can take the lead by researching and developing national, state, and local collaborative networks to incorporate effectively the food and nutrition services across the spectrum of aging.