Aging is associated with impaired learning and memory accompanied by reductions in adult hippocampal neurogenesis and brain expression of neurotrophic factors among other processes. Epigallocatechin-3-gallate (EGCG, a green tea catechin), β-alanine (β-ala, the precursor of carnosine), and exercise have independently been shown to be neuroprotective and to reduce inflammation and oxidative stress in the central nervous system. We hypothesized that EGCG, β-ala supplementation or exercise alone would improve learning and memory and increase neurogenesis in aged mice, and the combined intervention would be better than either treatment alone. Male Balb/cByJ mice (19 mo) were given AIN-93M diet with or without EGCG (182 mg/kg/d) and β-ala (417 mg/kg/d). Half of the mice were given access to a running wheel (VWR). The first 10 days, animals received 50 mg/kg bromodeoxyuridine (BrdU) daily. After 28 days, learning and memory was assessed by Morris water maze (MWM) and contextual fear conditioning (CFC). Brains were collected for immunohistochemical detection of BrdU and quantitative mRNA expression in the hippocampus. VWR increased the number of BrdU cells in the dentate gyrus, increased expression of brain-derived neurotrophic factor, decreased expression of the inflammatory cytokine interleukin-1β, and improved performance in the MWM and CFC tests. The dietary intervention reduced brain oxidative stress as measured by 4-hydroxynonenal in the cerebellum, but had no effect on BrdU labeling or behavioral performance. These results suggest that exercise, but not a diet containing EGCG and β-ala, exhibit pro-cognitive effects in aged mice when given at these doses in this relatively short time frame.

Nutrition and physical exercise can enhance cognitive function but the specific combinations of dietary bioactives that maximize pro-cognitive effects are not known nor are the contributing neurobiological mechanisms. Epigallocatechin-3-gallate (EGCG) is a flavonoid constituent of many plants with high levels found in green tea. EGCG has anti-inflammatory and anti-oxidant properties and is known to cross the blood brain barrier where it can affect brain chemistry and physiology. β-alanine (B-ALA) is a naturally occurring β–amino acid that could increase cognitive functioning by increasing levels of exercise via increased capacity of skeletal muscle, by crossing the blood brain barrier and acting as a neurotransmitter, or by free radical scavenging in muscle and brain after conversion into carnosine. The objective of this study was to determine the effects of EGCG (∼ 250 mg/kg/day), B-ALA (∼550 mg/kg/day), and their combination with voluntary wheel running exercise on the following outcome measures: body composition, time to fatigue, production of new cells in the granule layer of the dentate gyrus of the hippocampus as a marker for neuronal plasticity, and behavioral performance on the contextual and cued fear conditioning tasks, as measures of associative learning and memory. Young adult male BALB/cJ mice approximately 2 months old were randomized into 8 groups varying the nutritional supplement in their diet and access to running wheels over a 39 day study period. Running increased food intake, decreased fat mass, increased time to exhaustive fatigue, increased numbers of new cells in the granule layer of the hippocampus, and enhanced retrieval of both contextual and cued fear memories. The diets had no effect on their own or in combination with exercise on any of the fitness, plasticity, and behavioral outcome measures other than B-ALA decreased percent body fat whereas EGCG increased lean body mass slightly. Results suggest that, in young adult BALB/cJ mice, a 39 day treatment of exercise but not dietary supplementation with B-ALA or EGCG, enhances measures of fitness, neuroplasticity and cognition.

Aging leads to sarcopenia and loss of physical function. We examined whether voluntary wheel running, when combined with dietary supplementation with (-)-epigallocatechin-3-gallate (EGCG) and β-alanine (β-ALA), could improve muscle function and alter gene expression in the gastrocnemius of aged mice. Seventeen-month-old BALB/cByJ mice were given access to a running wheel or remained sedentary for 41 days while receiving either AIN-93M (standard feed) or AIN-93M containing 1.5 mg·kg(-1) EGCG and 3.43 mg·kg(-1) β-ALA. Mice underwent tests over 11 days from day 29 to day 39 of the study period, including muscle function testing (grip strength, treadmill exhaustive fatigue, rotarod). Following a rest day, mice were euthanized and gastrocnemii were collected for analysis of gene expression by quantitative PCR. Voluntary wheel running (VWR) improved rotarod and treadmill exhaustive fatigue performance and maintained grip strength in aged mice, while dietary intervention had no effect. VWR increased gastrocnemius expression of several genes, including those encoding interleukin-6 (Il6, p = 0.001), superoxide dismutase 1 (Sod1, p = 0.046), peroxisome proliferator-activated receptor gamma coactivator 1-α (Ppargc1a, p = 0.013), forkhead box protein O3 (Foxo3, p = 0.005), and brain-derived neurotrophic factor (Bdnf, p = 0.008), while reducing gastrocnemius levels of the lipid peroxidation marker 4-hydroxynonenal (p = 0.019). Dietary intervention alone increased gastrocnemius expression of Ppargc1a (p = 0.033) and genes encoding NAD-dependent protein deacetylase sirtuin-1 (Sirt1, p = 0.039), insulin-like growth factor I (Igf1, p = 0.003), and macrophage marker CD11b (Itgam, p = 0.016). Exercise and a diet containing β-ALA and EGCG differentially regulated gene expression in the gastrocnemius of aged mice, while VWR but not dietary intervention improved muscle function. We found no synergistic effects between dietary intervention and VWR.

Objective To examine the association between accelerometer activity counts and energy expenditure during walking in breast cancer survivors (BCS) compared with age‐matched healthy controls, and differences in moderate‐to‐vigorous physical activity (MVPA) cut‐points. Methods Using a case–control design, 19 BCS and 19 age‐matched women completed 6 min of resting energy expenditure and 6‐min periods of treadmill walking in Midwestern United States. Accelerometers and an open‐circuit spirometry system were used to measure activity counts and energy expenditure (VO2). A mixed‐factor analysis of variance was conducted on activity counts and VO2. Independent samples t tests compared the magnitude of associations between groups. Results There were group by speed interactions on energy expenditure (p < 0.001) and counts (p < 0.001). The linear association did not differ between BCS and controls for the R2 (p = 0.62) nor the slope (p = 0.43), but there was a difference in the intercept (p = 0.01). This resulted in different MVPA cut‐points between groups: 1,439 ± 761 counts·min−1 in BCS and 1,937 ± 639 counts·min−1 in controls. Conclusion The findings support the use of different cut‐points to quantify time spent in MVPA for BCS. Application of these cut‐points is warranted to accurately assess physical activity (PA) patterns for better prescription and health outcomes in PA programmes for BCS.

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Exercise improves muscle function and oxidative stress in the elderly. Several dietary interventions have been evaluated for their effects. Beta‐alanine (BA) improves muscle function, while epigallocatechin gallate (EGCG) is an antioxidant. Little is known about the interaction between exercise and diet. We examined the effects of voluntary wheel running (VWR) and/or supplementation with BA and EGCG on muscle function and oxidative stress in aged mice. Control diet (CTRL) or diet supplemented with 1.5 mg/g EGCG and 3.43 mg/g BA was given ad lib. to 17 month old male Balb/c mice for 4 weeks, during which they ran on a wheel or remained sedentary (SED). Mice then underwent muscle function tests over 11 days, and were euthanized 24 hours after the final test for tissue collection. Mice were maintained on diet and exercise interventions during the 11 day period. Diet and VWR did not differ in impact on body weight, food intake, or body composition. VWR maintained strength (p=.027) and improved performance on a treadmill (p=.001). VWR increased Nos2 and Sod2 gene expression in the gastrocnemius. There was a diet × VWR interaction (p=.012) such that the CTRL/SED group had non‐significantly increased gastrocnemius 4‐HNE levels compared to the other 3 groups. In conclusion, VWR but not a diet supplemented with BA and EGCG increased muscle function, whereas both VWR and BA/EGCG tended to reduce oxidative stress in aged muscle. Grant Funding Source: Supported by a grant from Abbott Nutrition.

Aging is associated with a decline in cognition in humans and rodents. Recently, these changes have been linked with decreased hippocampal neurogenesis. Physical exercise increases neurogenesis and reverses some of the cognitive deficits in elderly subjects, but the extent to which dietary supplementation may interact with physical exercise is unknown. Green tea contains high levels of epigallocatechin gallate (EGCG) that reduces age‐related cognitive decline. Similarly, β‐alanine (β‐Ala) may be beneficial against cognitive aging. We tested the hypothesis that exercise (voluntary wheel running) and dietary supplementation with EGCG (1.5mg/g) and β‐Ala (3.4 mg/g) would interact to improve cognition of aged mice. Balb/c mice (17 mo) served as sedentary controls or were provided access to running wheels for 4 weeks with or without EGCG + β‐Ala. The Morris water maze (MWM) and contextual fear conditioning (CFC) were used to assess learning and memory. Hippocampal neurogenesis was assessed by labeling new neurons with BrdU. Exercise improved cognition with increased platform crossings in the MWM and increased time spent frozen during CFC. Exercise also increased BDNF expression and diminished microglial activation in the hippocampus. Dietary supplementation did not affect any measurement. Collectively, these data verify that exercise has positive effects on neurogenesis and cognition of aged mice. Grant Funding Source: Supported by a grant from Abbott Nutrition to JAW

The influence of nutritional supplementation with Epigallacetechin gallate and β‐alanine in combination with physical exercise on adult hippocampal neurogenesis and contextual fear conditioning in young adult BALB/cJ mice. Nutritional supplementation and physical exercise can enhance cognitive function but the specific combinations of nutrients that maximize pro‐cognitive effects are not known nor are the contributing neurobiological mechanisms. Epigallacetechin gallate (EGCG) is a flavonoid constituent of green tea which has anti‐inflammatory and anti‐oxidant properties and is known to cross the the blood brain barrier and affect brain structure and function. β ‐alanine (B‐ALA) is a naturally occurring amino acid and could increase cognitive functioning by improving the exercise capacity of skeletal muscle. The objective of this study was to determine the effects of EGCG, B‐ALA, and their combination with physical exercise on adult hippocampal neurogenesis and performance on the contextual fear conditioning task in a mouse model. Young adult male BALB/cJ mice approximately 2 months old were divided into 8 groups varying the nutritional supplement in their diet and access to running wheels over a 30 day study period. Results indicated that exercise enhanced contextual fear conditioning; however the diets had no positive effect on performance. Additionally, running enhanced neurogenesis in the hippocampus, as well as BDNF and NOS2 gene expression. Dietary β‐alanine increased VEGF gene expression in the hippocampus, while the combination of β‐alanine and EGCG reduced CX3CL1 gene expression, which was recovered from exercise. EGCG combined with exercise enhanced NOS2 gene expression. These results suggest more work should be done to determine whether increased adult hippocampal neurogenesis from exercise directly contributed to the improved performance on the contextual fear conditioning task in the young BALB/cJ mice.