Resveratrol and exercise to treat functional limitations in late life: design of a randomized controlled trial

Effects of resveratrol on changes in trimethylamine-N-oxide and circulating cardiovascular factors following exercise training among older adults

PURPOSE

Trimethylamine-N-oxide (TMAO) is a gut-derived metabolite associated with cardiovascular disease (CVD). In preclinical and observational studies, resveratrol and exercise training have been suggested as potential strategies to reduce the systemic levels of TMAO. However, evidence from experimental studies in humans remains unknown. This project examined the dose-dependent effects of a combined resveratrol intervention with exercise training on circulating TMAO and other related metabolite signatures in older adults with high CVD risk.

METHODS

Forty-one older adults [mean (±SD) age of 72.1 (6.8) years] participated in a 12-week supervised center-based, multi-component exercise training intervention [2×/week; 80 min/session] and were randomized to one of two resveratrol dosages [Low: 500 vs. High:1000 mg/day] or a cellulose-based placebo. Serum/plasma were collected at baseline and post-intervention and evaluated for TMAO and associated analytes.

RESULTS

After the 12-week intervention, TMAO concentration increased over time, regardless of treatment [mean (±SD) Placebo: 11262 (±3970); Low:13252 (±1193); High: 12661(±3359) AUC; p = 0.04]. Each resveratrol dose produced different changes in metabolite signatures. Low dose resveratrol upregulated metabolites associated with bile acids biosynthesis (i.e., glycochenodeoxycholic acid, glycoursodeoxycholic acid, and glycocholic acid). High dose resveratrol modulated metabolites enriched for glycolysis, and pyruvate, propanoate, β-alanine, and tryptophan metabolism. Different communities tightly correlated to TMAO and resveratrol metabolites were associated with the lipid and vascular inflammatory clinical markers [|r| > 0.4, p < 0.05].

CONCLUSION

These findings suggest a distinct dose-dependent adaptation response to resveratrol supplementation on circulating metabolite signatures but not on TMAO among high-risk CVD older adults when combined with an exercise training intervention.

Muscle-Specific Cellular and Molecular Adaptations to Late-Life Voluntary Concurrent Exercise

Murine exercise models can provide information on factors that influence muscle adaptability with aging, but few translatable solutions exist. Progressive weighted wheel running (PoWeR) is a simple, voluntary, low-cost, high-volume endurance/resistance exercise approach for training young mice. In the current investigation, aged mice (22-mo-old) underwent a modified version of PoWeR for 8 wk. Muscle functional, cellular, biochemical, transcriptional, and myonuclear DNA methylation analyses provide an encompassing picture of how muscle from aged mice responds to high-volume combined training. Mice run 6-8 km/d, and relative to sedentary mice, PoWeR increases plantarflexor muscle strength. The oxidative soleus of aged mice responds to PoWeR similarly to young mice in every parameter measured in previous work; this includes muscle mass, glycolytic-to-oxidative fiber type transitioning, fiber size, satellite cell frequency, and myonuclear number. The oxidative/glycolytic plantaris adapts according to fiber type, but with modest overall changes in muscle mass. Capillarity increases markedly with PoWeR in both muscles, which may be permissive for adaptability in advanced age. Comparison to published PoWeR RNA-sequencing data in young mice identified conserved regulators of adaptability across age and muscles; this includes Aldh1l1 which associates with muscle vasculature. Agrn and Samd1 gene expression is upregulated after PoWeR simultaneous with a hypomethylated promoter CpG in myonuclear DNA, which could have implications for innervation and capillarization. A promoter CpG in Rbm10 is hypomethylated by late-life exercise in myonuclei, consistent with findings in muscle tissue. PoWeR and the data herein are a resource for uncovering cellular and molecular regulators of muscle adaptation with aging.

The effect of dietary (poly)phenols on exercise-induced physiological adaptations: A systematic review and meta-analysis of human intervention trials

We performed a systematic review and meta-analysis to determine whether (poly)phenol supplementation augments the physiological adaptations to exercise training. Eligible studies administered a (poly)phenol supplement alongside ≥2 weeks of supervised exercise in adult humans. After screening, 22 studies were included in the analysis. Isoflavones and green tea (poly)phenols were administered most frequently. Quality assessments suggested most studies were free from bias. (Poly)phenols had no effect on training-induced adaptations in muscle strength, peak power output, and V̇O_2max, but enhanced exercise capacity (SMD: 0.67, 95% CI: 0.25 to 1.09, p < 0.01). (Poly)phenols had no overall effect on fat loss (SMD: 0.10, 95% CI: -0.10 to 0.29; p = 0.97) or lean mass gains (SMD: 0.06, 95% CI: -0.18 to 0.30, p = 0.62) but sub-analysis suggested that isoflavones increased lean mass (SMD: 0.25, 95 CI%: -0.00 to 0.50, p = 0.05). Resveratrol impaired adaptations in two studies, although this was a non-statistically significant finding (SMD: -0.54, 95% CI: -1.15 to 0.07, p = 0.08). Our results suggest that isoflavones may augment aspects of the adaptive response to exercise training, while resveratrol may compromise training adaptations. More high-quality research is needed to resolve the effects of (poly)phenols on exercise training adaptations.

Resveratrol and exercise combined to treat functional limitations in late life: A pilot randomized controlled trial

PURPOSE

To evaluate the safety and feasibility of combining exercise (EX) and resveratrol to treat older adults with physical function limitations.

METHODS

Three-arm, two-site pilot randomized, controlled trial (RCT) for community-dwelling adults (N = 60), 71.8 ± 6.3 years of age with functional limitations. Participants were randomized to receive either 12 weeks of (1) EX + placebo [EX0], (2) EX + 500 mg/day resveratrol [EX500], or (3) EX + 1000 mg/day resveratrol [EX1000]. EX consisted of two sessions a week for 12 weeks of center-based walking and whole-body resistance training. Safety was assessed through adverse events and feasibility through exercise session and supplement (placebo, or resveratrol) protocol adherence. Outcome measures included a battery of indices of physical function as well as skeletal muscle mitchondrial function. Data were adjusted for age and gender using the Intent-To-Treat approach.

RESULTS

Adverse event frequency and type were similar between groups (n = 8 EX0, n = 12 EX500, and n = 7 EX1000). Overall, 85% of participants met the supplement adherence via pill counts while 82% met the exercise session adherence. Adjusted within group mean differences (95% confidence interval) from week 0 to 12 for gait speed ranged from -0.04 (EX0: -0.1, 0.03) m/s to 0.04 (EX1000: -0.02, 0.11) and the six-minute walk test mean differences were 9.45 (EX0: -9.02, 27.7), 22.9 (EX500: 4.18, 41.6), and 33.1 (EX1000: 13.8, 52.4) meters. Unadjusted mean differences for citrate synthase were -0.80 (EX0: -15.45, 13.84), -1.38 (EX500: -12.16, 9.39), and 7.75 (EX1000: -4.68, 20.18) mU/mg. COX activity mean within group changes ranged from -0.05 (EX0) to 0.06 (EX500) k/s/mg. Additional outcomes are detailed in the text.

CONCLUSION

The pilot RCT indicated that combined EX + resveratrol was safe and feasible for older adults with functional limitations and may improve skeletal muscle mitochondrial function and mobility-related indices of physical function. A larger trial appears warranted and is needed to formally test these hypotheses.

Natural constituents from food sources: potential therapeutic agents against muscle wasting

Skeletal muscle wasting is highly correlated with not only reduced quality of life but also higher morbidity and mortality. Although an increasing number of patients are suffering from various kinds of muscle atrophy and weakness, there is still no effective therapy available, and skeletal muscle is considered as an under-medicated organ. Food provided not only essential macronutrients but also functional substances involved in the modulation of the physiological systems of our body. Natural constituents from commonly consumed dietary plants, either extracts or compounds, have attracted more and more attention to be developed as agents for preventing and treating muscle wasting due to their safety and effectiveness, as well as structural diversity. This review provides an overview of the mechanistic aspects of muscle wasting, and summarizes the extracts and compounds from food sources as potential therapeutic agents against muscle wasting.