Giron Muriel, Thomas Muriel, Jarzaguet Marianne, Mayeur Camille, Ferrere Gladys, Noordine Marie-Louise, Bornes Stéphanie, Dardevet Dominique, Chassard Christophe, Savary-Auzeloux Isabelle
INRAE, UMR 1019, Unité de Nutrition Humaine, Université Clermont Auvergne, Clermont-Ferrand, France.
Université Paris-Saclay, INRAE UMR 1319, AgroParisTech, Micalis Institute, Jouy-en-Josas, France.
Front Nutr. 2022 Aug 10;9:928798. doi: 10.3389/fnut.2022.928798. eCollection 2022.
The aim of this study was to identify a probiotic-based strategy for maintaining muscle anabolism in the elderly. In previous research, we found that individuals experiencing short bowel syndrome (SBS) after an intestinal resection displayed beneficial metabolic adjustments that were mediated by their gut microbes. Thus, these bacteria could potentially be used to elicit similar positive effects in elderly people, who often have low food intake and thus develop sarcopenia. Gut bacterial strains from an SBS patient were evaluated for their ability to (1) maintain survival and muscle structure and (2) promote protein anabolism in a model of frail rodents (18-month-old rats on a food-restricted diet: 75% of consumption). We screened a first set of bacteria in and selected two strains (62 and 63) for further testing in the rat model. We had four experimental groups: control rats on an diet (AL); non-supplemented rats on the food-restricted diet (R); and two sets of food-restricted rats that received a daily supplement of one of the strains (∼10 CFU; R+62 and R+63). We measured lean mass, protein metabolism, insulin resistance, cecal short-chain fatty acids (SCFAs), and SCFA receptor expression in the gut. Food restriction led to decreased muscle mass [-10% vs. AL ( < 0.05)]. Supplementation with strain 63 tempered this effect [-2% vs. AL ( > 0.1)]. The mechanism appeared to be the stimulation of the insulin-sensitive p-S6/S6 and p-eIF2α/eIF2α ratios, which were similar in the R+63 and AL groups ( > 0.1) but lower in the R group ( < 0.05). We hypothesize that greater SCFA receptor sensitivity in the R+63 group promoted gut-muscle cross talk [GPR41: +40% and GPR43: +47% vs. R ( < 0.05)]. Hence, strain 63 could be used in association with other nutritional strategies and exercise regimes to limit sarcopenia in frail elderly people.
本研究的目的是确定一种基于益生菌的策略来维持老年人的肌肉合成代谢。在先前的研究中,我们发现肠道切除术后患有短肠综合征(SBS)的个体表现出有益的代谢调节,这是由其肠道微生物介导的。因此,这些细菌有可能用于在老年人中引发类似的积极作用,老年人通常食物摄入量低,因此会出现肌肉减少症。评估了一名SBS患者的肠道细菌菌株在以下方面的能力:(1)维持生存和肌肉结构,以及(2)在体弱的啮齿动物模型(18个月大的大鼠,饮食受限:消耗量的75%)中促进蛋白质合成代谢。我们在体外筛选了第一组细菌,并选择了两个菌株(62和63)在大鼠模型中进行进一步测试。我们有四个实验组:正常饮食的对照大鼠(AL);饮食受限的未补充大鼠(R);以及两组饮食受限的大鼠,它们每天补充其中一种菌株(约10⁹CFU;R+62和R+63)。我们测量了瘦体重、蛋白质代谢、胰岛素抵抗、盲肠短链脂肪酸(SCFA)以及肠道中SCFA受体的表达。饮食限制导致肌肉量减少[-10% vs. AL(P<0.05)]。补充菌株63减轻了这种影响[-2% vs. AL(P>0.1)]。其机制似乎是刺激了胰岛素敏感性的p-S6/S6和p-eIF2α/eIF2α比值,这在R+63组和AL组中相似(P>0.1),但在R组中较低(P<0.05)。我们推测R+63组中更高的SCFA受体敏感性促进了肠道与肌肉的相互作用[GPR41:+40%,GPR43:+47% vs. R(P<0.05)]。因此,菌株63可与其他营养策略和运动方案联合使用,以限制体弱老年人的肌肉减少症。