Beneficial effects of dietary supplementation with green tea catechins and cocoa flavanols on aging-related regressive changes in the mouse neuromuscular system.

Sílvia Gras,Suzette L Pereira,Alejandro Barranco,Alba Blasco,Xavier Navarro,Ricardo Rueda,Josep E Esquerda,Jordi Calderó,Lídia Piedrafita,Tapas Das,Guillem Mòdol-Caballero,Anna Casanovas,Olga Tarabal

doi:10.18632/aging.203336

Abstract

Besides skeletal muscle wasting, sarcopenia entails morphological and molecular changes in distinct components of the neuromuscular system, including spinal cord motoneurons (MNs) and neuromuscular junctions (NMJs); moreover, noticeable microgliosis has also been observed around aged MNs. Here we examined the impact of two flavonoid-enriched diets containing either green tea extract (GTE) catechins or cocoa flavanols on age-associated regressive changes in the neuromuscular system of C57BL/6J mice. Compared to control mice, GTE- and cocoa-supplementation significantly improved the survival rate of mice, reduced the proportion of fibers with lipofuscin aggregates and central nuclei, and increased the density of satellite cells in skeletal muscles. Additionally, both supplements significantly augmented the number of innervated NMJs and their degree of maturity compared to controls. GTE, but not cocoa, prominently increased the density of VAChT and VGluT2 afferent synapses on MNs, which were lost in control aged spinal cords; conversely, cocoa, but not GTE, significantly augmented the proportion of VGluT1 afferent synapses on aged MNs. Moreover, GTE, but not cocoa, reduced aging-associated microgliosis and increased the proportion of neuroprotective microglial phenotypes. Our data indicate that certain plant flavonoids may be beneficial in the nutritional management of age-related deterioration of the neuromuscular system.

Highlights

Sarcopenia, the progressive loss of skeletal muscle mass and function with age, is considered the main causative factor of the physical performance decline in the elderly.The compromised muscular function associated to sarcopenia has a negative impact on the life quality of older adults and increases the risk for adverse health outcomes including disability, fall-associated injuries, morbidity, and mortality [1]
Starting at age of 92 weeks (21 months), mice were fed with a standard (AIN-93M) diet or AIN-93M diet supplemented with either green tea extract (GTE) (GTE group) or cocoa flavanols
No significant differences in body weight were observed between animals of control and cocoa groups; mice fed with GTE-enriched diet exhibited, at 111-115 weeks of age, significantly reduced body weights compared with control animals (Figure 1C)

Summary

Introduction

Sarcopenia, the progressive loss of skeletal muscle mass and function with age, is considered the main causative factor of the physical performance decline in the elderly. The compromised muscular function associated to sarcopenia has a negative impact on the life quality of older adults and increases the risk for adverse health outcomes including disability, fall-associated injuries, morbidity, and mortality [1]. All these aspects stress www.aging-us.com healthcare systems, increasing the care needs of older people and their costs. Sarcopenia in the elderly is presently considered a complex multifactorial condition which involves intrinsic and extrinsic causative factors (reviewed by [5]); among of them, chronic inflammation, metabolic and endocrine alterations, poor nutrition, mitochondrial dysfunction, oxidative damage, and neurogenic factors, appear to play an important role in sarcopenia

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