ABSTRACT
Layer 3 (L3) pyramidal neurons in aged rhesus monkey lateral prefrontal cortex (LPFC) exhibit significantly elevated excitability in vitro and reduced spine density compared to neurons in young subjects. The time-course of these alterations, and whether they can be ameliorated in middle age by the powerful anti-oxidant curcumin is unknown. We compared the properties of L3 pyramidal neurons from the LPFC of behaviorally characterized rhesus monkeys over the adult lifespan using whole-cell patch clamp recordings and neuronal reconstructions. Working memory (WM) impairment, neuronal hyperexcitability, and spine loss began in middle age. There was no significant relationship between neuronal properties and WM performance. Middle-aged subjects given curcumin exhibited better WM performance and less neuronal excitability compared to control subjects. These findings suggest that the appropriate time frame for intervention for age-related cognitive changes is early middle age, and points to the efficacy of curcumin in delaying WM decline. Because there was no relationship between excitability and behavior, the effects of curcumin on these measures appear to be independent.
Subject(s)
Aging/drug effects , Aging/pathology , Curcumin/administration & dosage , Curcumin/pharmacology , Dietary Supplements , Memory, Short-Term/drug effects , Memory, Short-Term/physiology , Prefrontal Cortex/drug effects , Prefrontal Cortex/pathology , Pyramidal Cells/drug effects , Pyramidal Cells/pathology , Age Factors , Aging/psychology , Animals , Female , Macaca mulatta , Male , Patch-Clamp Techniques , Pyramidal Cells/physiology , Time FactorsABSTRACT
Calcium intake is critical for adequate bone mineralization in adolescence, but it is usually inadequate in US adolescents. A strategy to maximize bone mineralization is to increase calcium absorption, which could be achieved by soluble corn fiber (SCF). There are no studies determining the long-term effects of SCF on bone mass in children. OBJECTIVES: To determine the effect of one-year SCF supplementation compared to placebo on bone mass and bone biomarkers in children with low habitual calcium intake. We hypothesize that SCF supplementation will result in a higher bone mineral content and higher levels of bone formation and lower bone resorption biomarkers. METHODS: 240 healthy children (10-13â¯years), with usual low calcium intake, will be randomized to four experimental groups for 1â¯year: (1) SCF (12â¯g/d); (2) SCF (12â¯g/d)â¯+â¯600â¯mg/d of calcium; (3) Placebo (maltodextrin); and (4) Placebo +600â¯mg/d of calcium. The supplements have been pre-mixed with a flavored powder beverage and participants will only need to dilute it in water and drink this twice per day. Bone will be measured using dual energy x-ray absorptiometry (DXA) at baseline, 6 and 12â¯months. Serum bone biomarkers will be measured at baseline and at 12â¯months. CONCLUSIONS: If supplementing diets with SCF lead to higher bone mass during adolescence, this could help achieve the genetic potential for PBM and to start adult life with stronger bones. If successful, SCF can be incorporated into diets for promoting bone health in adolescents.
Subject(s)
Calcium, Dietary , Zea mays , Absorptiometry, Photon , Adolescent , Adult , Bone Density , Bone and Bones , Child , Dietary Supplements , HumansABSTRACT
Eggs contain bioactive compounds thought to benefit pediatric bone. This cross-sectional study shows a positive link between childhood egg intake and radius cortical bone. If randomized trials confirm our findings, incorporating eggs into children's diets could have a significant impact in preventing childhood fractures and reducing the risk of osteoporosis. INTRODUCTION: This study examined the relationships between egg consumption and cortical bone in children. METHODS: The cross-sectional study design included 294 9-13-year-old black and white males and females. Three-day diet records determined daily egg consumption. Peripheral quantitative computed tomography measured radius and tibia cortical bone. Body composition and biomarkers of bone turnover were assessed using dual-energy X-ray absorptiometry and ELISA, respectively. RESULTS: Egg intake was positively correlated with radius and tibia cortical bone mineral content (Ct.BMC), total bone area, cortical area, cortical thickness, periosteal circumference, and polar strength strain index in unadjusted models (r = 0.144-0.224, all P < 0.050). After adjusting for differences in race, sex, maturation, fat-free soft tissue mass (FFST), and protein intakes, tibia relationships were nullified; however, egg intake remained positively correlated with radius Ct.BMC (r = 0.138, P = 0.031). Egg intake positively correlated with total body bone mineral density, BMC, and bone area in the unadjusted models only (r = 0.119-0.224; all P < 0.050). After adjusting for covariates, egg intake was a positive predictor of radius FFST (ß = 0.113, P < 0.050) and FFST was a positive predictor of Ct.BMC (ß = 0.556, P < 0.050) in path analyses. There was a direct influence of egg on radius Ct.BMC (ß = 0.099, P = 0.035), even after adjusting for the mediator, FFST (ß = 0.137, P = 0.020). Egg intake was positively correlated with osteocalcin in both the unadjusted (P = 0.005) and adjusted (P = 0.049) models. CONCLUSION: If the positive influence of eggs on Ct.BMC observed in this study is confirmed through future randomized controlled trials, whole eggs may represent a viable strategy to promote pediatric bone development and prevent fractures.
Subject(s)
Bone Density/physiology , Child Nutritional Physiological Phenomena/physiology , Cortical Bone/physiology , Eggs/statistics & numerical data , Absorptiometry, Photon , Adolescent , Anthropometry/methods , Biomarkers/blood , Bone Development/physiology , Bone Remodeling/physiology , Child , Cross-Sectional Studies , Diet/statistics & numerical data , Feeding Behavior/physiology , Female , Humans , Male , Radius/physiology , Sexual Maturation/physiology , Tibia/physiology , Tomography, X-Ray Computed/methodsABSTRACT
Low bone mass leads to fracture risk. Osteoporosis affects over 10% of the population and one of every two women over the age of 50 years. Genetics predicts more than half of bone mass. Diet and weight bearing exercise are two lifestyle choices that can influence the risk of fracture. Nutrients are the structural constituents of bone. As bone is a living tissue and turns over, albeit more slowly than other tissues, there is an obligatory loss of minerals daily that must be replaced through diet. Three servings of dairy products daily are recommended to replace those losses. Alternative sources of nutrients can come from calcium fortified orange juice, plant-based beverages, or tofu to provide many nutrients needed for bone health. Supplements can provide nutrients at risk for being inadequate such as calcium or vitamin D.
Subject(s)
Diet , Osteoporosis/prevention & control , Bone Density , Bone Remodeling , Dietary Supplements , Humans , Osteoporosis/etiology , Protective Factors , Recommended Dietary Allowances , Risk FactorsABSTRACT
The rare, long-lived radiotracer, 41Ca, measured by accelerator mass spectrometry in the urine or serum following incorporation into the bone provides an ultra-sensitive tool to assess changes in bone calcium balance in response to an intervention. Changes in bone balance can be followed for years with one small dose that is both radiologically and biologically non-invasive. Sequential interventions can be compared, with greater precision than they can with biochemical markers of bone turnover and with greater power than with bone densitometry. This method is especially useful to screen interventions over a period of weeks. The development and validation of this tool and its applications are reviewed. Mini abstract: Use of 41Ca measured in the urine or blood by accelerator mass spectrometry to assess bone balance provides a tool to compare the relative efficacy of multiple interventions. This perspective provides insights in the use of this novel method and comparisons with more traditional methods for evaluating the efficacy of interventions.
Subject(s)
Bone Remodeling/physiology , Bone and Bones/metabolism , Calcium Radioisotopes , Animals , Calcium/metabolism , Calcium Radioisotopes/administration & dosage , Calcium Radioisotopes/urine , Humans , Models, AnimalABSTRACT
Lifestyle choices influence 20-40 % of adult peak bone mass. Therefore, optimization of lifestyle factors known to influence peak bone mass and strength is an important strategy aimed at reducing risk of osteoporosis or low bone mass later in life. The National Osteoporosis Foundation has issued this scientific statement to provide evidence-based guidance and a national implementation strategy for the purpose of helping individuals achieve maximal peak bone mass early in life. In this scientific statement, we (1) report the results of an evidence-based review of the literature since 2000 on factors that influence achieving the full genetic potential for skeletal mass; (2) recommend lifestyle choices that promote maximal bone health throughout the lifespan; (3) outline a research agenda to address current gaps; and (4) identify implementation strategies. We conducted a systematic review of the role of individual nutrients, food patterns, special issues, contraceptives, and physical activity on bone mass and strength development in youth. An evidence grading system was applied to describe the strength of available evidence on these individual modifiable lifestyle factors that may (or may not) influence the development of peak bone mass (Table 1). A summary of the grades for each of these factors is given below. We describe the underpinning biology of these relationships as well as other factors for which a systematic review approach was not possible. Articles published since 2000, all of which followed the report by Heaney et al. [1] published in that year, were considered for this scientific statement. This current review is a systematic update of the previous review conducted by the National Osteoporosis Foundation [1]. [Table: see text] Considering the evidence-based literature review, we recommend lifestyle choices that promote maximal bone health from childhood through young to late adolescence and outline a research agenda to address current gaps in knowledge. The best evidence (grade A) is available for positive effects of calcium intake and physical activity, especially during the late childhood and peripubertal years-a critical period for bone accretion. Good evidence is also available for a role of vitamin D and dairy consumption and a detriment of DMPA injections. However, more rigorous trial data on many other lifestyle choices are needed and this need is outlined in our research agenda. Implementation strategies for lifestyle modifications to promote development of peak bone mass and strength within one's genetic potential require a multisectored (i.e., family, schools, healthcare systems) approach.
Subject(s)
Bone Density/physiology , Bone Development/physiology , Life Style , Osteoporosis/prevention & control , Absorptiometry, Photon/methods , Aging/physiology , Body Composition/physiology , Evidence-Based Medicine/methods , Exercise/physiology , Humans , Nutritional Physiological Phenomena/physiology , Osteoporotic Fractures/prevention & control , Tomography, X-Ray Computed/methods , Weight-Bearing/physiologyABSTRACT
UNLABELLED: The aim was to meta-analyze randomized controlled trials of calcium plus vitamin D supplementation and fracture prevention. Meta-analysis showed a significant 15 % reduced risk of total fractures (summary relative risk estimate [SRRE], 0.85; 95 % confidence interval [CI], 0.73-0.98) and a 30 % reduced risk of hip fractures (SRRE, 0.70; 95 % CI, 0.56-0.87). INTRODUCTION: Calcium plus vitamin D supplementation has been widely recommended to prevent osteoporosis and subsequent fractures; however, considerable controversy exists regarding the association of such supplementation and fracture risk. The aim was to conduct a meta-analysis of randomized controlled trials [RCTs] of calcium plus vitamin D supplementation and fracture prevention in adults. METHODS: A PubMed literature search was conducted for the period from July 1, 2011 through July 31, 2015. RCTs reporting the effect of calcium plus vitamin D supplementation on fracture incidence were selected from English-language studies. Qualitative and quantitative information was extracted; random-effects meta-analyses were conducted to generate summary relative risk estimates (SRREs) for total and hip fractures. Statistical heterogeneity was assessed using Cochran's Q test and the I (2) statistic, and potential for publication bias was assessed. RESULTS: Of the citations retrieved, eight studies including 30,970 participants met criteria for inclusion in the primary analysis, reporting 195 hip fractures and 2231 total fractures. Meta-analysis of all studies showed that calcium plus vitamin D supplementation produced a statistically significant 15 % reduced risk of total fractures (SRRE, 0.85; 95 % confidence interval [CI], 0.73-0.98) and a 30 % reduced risk of hip fractures (SRRE, 0.70; 95 % CI, 0.56-0.87). Numerous sensitivity and subgroup analyses produced similar summary associations. A limitation is that this study utilized data from subgroup analysis of the Women's Health Initiative. CONCLUSIONS: This meta-analysis of RCTs supports the use of calcium plus vitamin D supplements as an intervention for fracture risk reduction in both community-dwelling and institutionalized middle-aged to older adults.
Subject(s)
Bone Density Conservation Agents/therapeutic use , Calcium/therapeutic use , Dietary Supplements , Osteoporotic Fractures/prevention & control , Vitamin D/therapeutic use , Drug Therapy, Combination , Humans , Osteoporosis, Postmenopausal/complications , Osteoporosis, Postmenopausal/drug therapy , Osteoporotic Fractures/etiology , Randomized Controlled Trials as Topic , Risk Assessment/methodsABSTRACT
CONTEXT: Although animal studies suggest that adenovirus 36 (Ad36) infection is linked to obesity and systemic inflammation, human data are scant and equivocal. OBJECTIVE: Associations of Ad36 infection with total body adiposity and inflammatory-related markers were determined in 291 children aged 9-13 years (50% female, 49% black). DESIGN: Fasting blood samples were measured for presence of Ad36-specific antibodies and TNF-α, IL-6, vascular endothelial growth factor (VEGF), and monocyte chemoattractant protein-1 (MCP-1). Fat mass and fat-free soft tissue mass were measured by dual-energy X-ray absorptiometry. RESULTS: The overall prevalence of Ad36 seropositivity [Ad36(+)] was 42%. There was a higher percentage of Ad36(+) children in the highest tertiles of TNF-α and IL-6 compared with their respective middle and lowest tertiles (both P < .03). There was also a trend toward a higher prevalence of Ad36(+) children in the highest tertile of VEGF compared with tertiles 1 and 2 (P = .05). Multinomial logistic regression, adjusting for age, race, sex, and fat-free soft tissue mass, revealed that compared with children with the lowest TNF-α, IL-6, and VEGF levels (tertile 1), the adjusted odds ratios for Ad36(+) were 2.2 [95% confidence interval (CI) 1.2-4.0], 2.4 (95% CI 1.4-4.0), and 1.8 (95% CI 1.0-3.3), respectively, for those in the highest TNF-α, IL-6, and VEGF levels (tertile 3). No association was observed between Ad36(+) and greater levels of fat mass or MCP-1 (all P > .05). CONCLUSIONS: In children, our data suggest that Ad36(+) may be associated with biomarkers implicated in inflammation but not with greater levels of fat mass.
Subject(s)
Adenoviridae/immunology , Adenovirus Infections, Human/epidemiology , Adenovirus Infections, Human/immunology , Adiposity/immunology , Inflammation/epidemiology , Inflammation/immunology , Adolescent , Antibodies, Viral/blood , Biomarkers/blood , Chemokine CCL2/blood , Child , Female , Humans , Interleukin-6/blood , Male , Odds Ratio , Prevalence , Seroepidemiologic Studies , Tumor Necrosis Factor-alpha/blood , Vascular Endothelial Growth Factor A/bloodABSTRACT
SUMMARY: Urinary excretion of calcium tracers in labeled individuals decreases in response to antiresorptive therapy, providing a tool to rapidly screen potential therapies. Using teriparatide, we demonstrate in this study that anabolic therapy also decreases tracer excretion, confirming that this method can also be used to screen potential anabolic therapies. INTRODUCTION: Changes in urinary excretion of calcium tracers from a labeled skeleton may be a rapid and sensitive method to screen potential therapies for osteoporosis. This method has been used to screen antiresorptive therapies, but the effect of anabolic therapies on tracer excretion is unknown. METHODS: Eight-month-old female Sprague Dawley rats (n = 11) were given 50 µCi (45)Ca iv. After a 1-month equilibration period, baseline urinary (45)Ca excretion and total bone mineral content (BMC) were measured. Rats were then treated with 30 µg/kg teriparatide sc per day, a bone anabolic agent, for 80 days. Urine was collected throughout the study and analyzed for (45)Ca and total Ca, and BMC was measured at the beginning and end of the study. RESULTS: Teriparatide decreased urinary (45)Ca excretion by 52.1 % and increased BMC by 21.7 %. The change in bone calcium retention as determined by the ratio of (45)Ca to total Ca excretion in urine from day 6 through 15 of teriparatide treatment was significantly correlated (p = 0.036) with the change in BMC after 80 days of teriparatide treatment. CONCLUSION: Urinary excretion of calcium tracers from labeled bone is an effective method to rapidly screen potential anabolic therapies for osteoporosis.
Subject(s)
Bone Density Conservation Agents/therapeutic use , Calcium Radioisotopes , Drug Evaluation, Preclinical/methods , Osteoporosis/drug therapy , Teriparatide/therapeutic use , Animals , Bone Density/drug effects , Bone Density Conservation Agents/pharmacology , Bone and Bones/metabolism , Calcium Radioisotopes/urine , Female , Osteoporosis/physiopathology , Radiopharmaceuticals/urine , Rats, Sprague-Dawley , Teriparatide/pharmacologyABSTRACT
UNLABELLED: The interaction of habitual Ca and vitamin D intake from preovariectomy to 4 months postovariectomy on bone and Ca metabolism was assessed. Higher Ca intake suppressed net bone turnover, and both nutrients independently benefitted trabecular structure. Habitual intake of adequate Ca and ~50 nmol/L vitamin D status is most beneficial. INTRODUCTION: Dietary strategies to benefit bone are typically tested prior to or after menopause but not through menopause transition. We investigated the interaction of Ca and vitamin D status on Ca absorption, bone remodeling, Ca kinetics, and bone strength as rats transitioned through estrogen deficiency. METHODS: Sprague Dawley rats were randomized at 8 weeks to 0.2 or 1.0 % Ca and 50, 100, or 1,000 IU (1.25, 2.5, or 25 µg) vitamin D/kg diet (2 × 3 factorial design) and ovariectomized at 12 weeks. Urinary (45)Ca excretion from deep-labeled bone was used to assess net bone turnover weekly. Ca kinetics was performed between 25 and 28 weeks. Rats were killed at 29 weeks. Femoral and tibiae structure (by µCT), dynamic histomorphometry, and bone Ca content were assessed. RESULTS: Mean 25(OH)D for rats on the 50, 100, 1,000 IU vitamin D/kg diet were 32, 54, and 175 nmol/L, respectively. Higher Ca intake ameliorated net bone turnover, reduced fractional Ca absorption and bone resorption, and increased net Ca absorption. Tibial and femoral trabecular structures were enhanced independently by higher Ca and vitamin D intake. Tibial bone width and fracture resistance were enhanced by higher vitamin D intake. Dynamic histomorphometry in the tibia was not affected by either nutrient. A Ca × vitamin D interaction existed in femur length, tibial Ca content, and mass of the soft tissue/extracellular fluid compartment. CONCLUSIONS: Adequate Ca intake and serum 25(OH)D level of 50 nmol/L provided the most benefit for bone health, mostly through independent effects of Ca and vitamin D.
Subject(s)
Bone Remodeling/physiology , Calcium, Dietary/administration & dosage , Menopause/physiology , Vitamin D/administration & dosage , Animals , Biomechanical Phenomena , Bone Density/drug effects , Bone Density/physiology , Bone Remodeling/drug effects , Bone Resorption/physiopathology , Bone Resorption/prevention & control , Calcium Radioisotopes , Calcium, Dietary/pharmacokinetics , Calcium, Dietary/pharmacology , Feces/chemistry , Female , Intestinal Absorption/physiology , Menopause/metabolism , Ovariectomy , Rats, Sprague-Dawley , Tibia/physiology , Vitamin D/analogs & derivatives , Vitamin D/blood , Vitamin D/pharmacologyABSTRACT
The 2011 vitamin D recommendations set by the Food and Nutrition Board of the Institute of Medicine was the first time that Estimated Average Requirements (EAR) and Recommended Dietary Allowance (RDA) were given for vitamin D. Previous versions (i.e., 1997 and earlier) used Adequate Intakes, implying less certainty of evidence to determine the EAR. It is difficult to set requirements for vitamin D because it behaves more like a hormone than a nutrient and because diet is not the only source of vitamin D. In fact, more vitamin D comes from cutaneous production than from diet for most people. Therefore, one cannot use the common factorial approach of estimating daily losses adjusted by absorption and needs during growth to set intake recommendations. The basis for the 2011 vitamin D recommendations was for bone health. Systematic reviews showed vitamin D status levels associated with calcium absorption, bone mineral density, and risk of osteomalacia or rickets. An integrated model was used to set vitamin D status, measured by serum 25-hydroxyvitamin D (25(OH)D) levels, at 40 nM for the EAR and 50 nM for the RDA. Vitamin D intakes to achieve these levels became the recommended intakes based on a nonlinear model of the relationship of vitamin D intake and achieved serum 25(OH)D levels. The panel assumed all vitamin D intakes should come from diet in their recommendations because many groups are not exposed to UVB light, are elderly or are dark skinned, which limits cutaneous production. However, intakes are well below recommended levels. Clinical guidelines for patients at risk for vitamin D deficiency were also established in 2011 by the Endocrine Society, which gives physicians more latitude for vitamin D recommendations.
Subject(s)
Recommended Dietary Allowances , Vitamin D/administration & dosage , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Lactation , Male , Middle Aged , Pregnancy , Young AdultABSTRACT
CONTEXT: Changes in serum vitamin D metabolites and calcium absorption with varying doses of oral vitamin D3 in healthy children are unknown. OBJECTIVE: Our objective was to examine the dose-response effects of supplemental vitamin D3 on serum vitamin D metabolites and calcium absorption in children living at two U.S. latitudes. DESIGN: Black and white children (n = 323) participated in a multisite (U.S. latitudes 34° N and 40° N), triple-masked trial. Children were randomized to receive oral vitamin D3 (0, 400, 1000, 2000, and 4000 IU/d) and were sampled over 12 weeks in winter. Serum 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)2D) were measured using RIA and intact PTH (iPTH) by immunoradiometric assay. Fractional calcium absorption was determined from an oral stable isotope 44Ca (5 mg) in a 150-mg calcium meal. Nonlinear and linear regression models were fit for vitamin D metabolites, iPTH, and calcium absorption. RESULTS: The mean baseline 25(OH)D value for the entire sample was 70.0 nmol/L. Increases in 25(OH)D depended on dose with 12-week changes ranging from -10 nmol/L for placebo to 76 nmol/L for 4000 IU. Larger 25(OH)D gains were observed for whites vs blacks at the highest dose (P < .01). Gains for 1,25(OH)2D were not significant (P = .07), and decreases in iPTH were not dose-dependent. There was no dose effect of vitamin D on fractional calcium absorption when adjusted for pill compliance, race, sex, or baseline 25(OH)D. CONCLUSION: Large increases in serum 25(OH)D with vitamin D3 supplementation did not increase calcium absorption in healthy children living at 2 different latitudes. Supplementation with 400 IU/d was sufficient to maintain wintertime 25(OH)D concentrations in healthy black, but not white, children.
Subject(s)
Calcium, Dietary/metabolism , Child Development , Cholecalciferol/administration & dosage , Dietary Supplements , Intestinal Absorption , Models, Biological , Vitamin D Deficiency/prevention & control , Adolescent , Black or African American , Calcifediol/blood , Calcifediol/metabolism , Calcitriol/blood , Calcitriol/metabolism , Child , Cholecalciferol/adverse effects , Cholecalciferol/metabolism , Cholecalciferol/therapeutic use , Dietary Supplements/adverse effects , Double-Blind Method , Female , Georgia , Humans , Indiana , Intestinal Absorption/ethnology , Male , Parathyroid Hormone/blood , Parathyroid Hormone/metabolism , Seasons , Sunlight , Vitamin D Deficiency/blood , Vitamin D Deficiency/ethnology , Vitamin D Deficiency/metabolism , White PeopleABSTRACT
Wild mushrooms are an excellent source of vitamin D. The presence of vitamin D in mushrooms is attributed to sunlight exposure, which catalyzes the conversion of fungal ergosterol to vitamin D2 via a series of photochemical/thermal reactions. Mushroom growers now incorporate UV light treatments during processing to produce mushrooms with levels of vitamin D that compare to those in wild mushrooms. Presented herein is a comprehensive review of information relevant to the safety of introducing vitamin D mushrooms, produced using UV light technologies, to the food supply. Historical reference to the use of UV light for production of vitamin D is discussed, and studies evaluating the nutritional value and safety of vitamin D mushrooms are reviewed. Traditional safety evaluation practices for food additives are not applicable to whole foods; therefore, the application of substantial equivalence and history-of-safe-use is presented. It was demonstrated that vitamin D in mushrooms, produced using UV light technologies, are equivalent to vitamin D in mushrooms exposed to sunlight, and that UV light has a long-history of safe use for production of vitamin D in food. Vitamin D mushrooms produced using UV light technologies were therefore considered safe and suitable for introduction to the marketplace.
Subject(s)
Agaricales/radiation effects , Nutritive Value/radiation effects , Ultraviolet Rays , Vitamin D/analysis , Vitamins/analysis , Agaricales/chemistry , Animals , Food Technology/methods , Humans , SunlightABSTRACT
Given the rapid rate of population aging and the increased incidence of cognitive decline and neurodegenerative diseases with advanced age, it is important to ascertain the determinants that result in cognitive impairment. It is also important to note that much of the aged population exhibit 'successful' cognitive aging, in which cognitive impairment is minimal. One main goal of normal aging studies is to distinguish the neural changes that occur in unsuccessful (functionally impaired) subjects from those of successful (functionally unimpaired) subjects. In this review, we present some of the structural adaptations that neurons and spines undergo throughout normal aging and discuss their likely contributions to electrophysiological properties and cognition. Structural changes of neurons and dendritic spines during aging, and the functional consequences of such changes, remain poorly understood. Elucidating the structural and functional synaptic age-related changes that lead to cognitive impairment may lead to the development of drug treatments that can restore or protect neural circuits and mediate cognition and successful aging.