Sarcopenia Is a Cause and Consequence of Metabolic Dysregulation in Aging Humans: Effects of Gut Dysbiosis, Glucose Dysregulation, Diet and Lifestyle

Abstract

Skeletal muscle mass plays a critical role in a healthy lifespan by helping to regulate glucose homeostasis. As seen in sarcopenia, decreased skeletal muscle mass impairs glucose homeostasis, but it may also be caused by glucose dysregulation. Gut microbiota modulates lipopolysaccharide (LPS) production, short-chain fatty acids (SCFA), and various metabolites that affect the host metabolism, including skeletal muscle tissues, and may have a role in the sarcopenia etiology. Here, we aimed to review the relationship between skeletal muscle mass, glucose homeostasis, and gut microbiota, and the effect of consuming probiotics and prebiotics on the development and pathological consequences of sarcopenia in the aging human population. This review includes discussions about the effects of glucose metabolism and gut microbiota on skeletal muscle mass and sarcopenia and the interaction of dietary intake, physical activity, and gut microbiome to influence sarcopenia through modulating the gut–muscle axis. Emerging evidence suggests that the microbiome can regulate both skeletal muscle mass and function, in part through modulating the metabolisms of short-chain fatty acids and branch-chain amino acids that might act directly on muscle in humans or indirectly through the brain and liver. Dietary factors such as fats, proteins, and indigestible carbohydrates and lifestyle interventions such as exercise, smoking, and alcohol intake can both help and hinder the putative gut–muscle axis. The evidence presented in this review suggests that loss of muscle mass and function are not an inevitable consequence of the aging process, and that dietary and lifestyle interventions may prevent or delay sarcopenia.

The Contribution of Diet Therapy and Probiotics in the Treatment of Sarcopenia Induced by Prolonged Immobilization Caused by the COVID-19 Pandemic

“…There is increasing evidence that the gut microbiome influences muscle physiology in a number of disorders that cause muscular atrophy [ 44 ]. It is proven that the intake of specific probiotics, modifying the intestinal microbiota, favors the increase in skeletal muscle mass [ 45 ].…”

“…In the present study, diet therapy and probiotics were recommended for two months. Moreover, vitamin D intake is essential (daily supplementation of 400 IU), which can have prognostic importance, and the connection between vitamin D deficiency and severe infections is recognized [ 45 ].…”

“…Studies on animals (mice) demonstrate the effects of Lactobacillus plantarum , with a role in increasing muscle strength and the number of slow-twitch muscles; administration of Bifidobacterium breve B-3 to mice stimulates mitochondrial biogenesis (by increasing phosphorylation and activating the transcriptional coactivator involved in biogenesis, PGC-1α). Lactobacillus reuteri modulates the transcription factor N1, with a role in delaying the onset of cachexia in mice with cancer [ 45 ]. It was taken into account that the anti-inflammatory properties of Lactobacilli might prevent muscular atrophy, which was studied on cachexia mice models [ 54 ].…”

Weight cycling based on altered immune microenvironment as a result of metaflammation

“…During the WR phase, adipose tissue swells significantly, and the inflammatory state is exacerbated, whereas muscle does not significantly recover, and its local inflammatory state is maintained [ 16 ]. Muscle loss and fat accumulation create a vicious cycle that increases metaflammation via a complex interaction between proinflammatory cytokines, oxidative stress, effects on insulin secretion and glucose tolerance, and mitochondrial dysfunction [ 16 , 57 ] (Fig. 2 ).…”

Effects of Bile Acid Modulation by Dietary Fat, Cholecystectomy, and Bile Acid Sequestrant on Energy, Glucose, and Lipid Metabolism and Gut Microbiota in Mice

“…Eliminating mucus and producing metabolites influences energy and glucose metabolism, inflammation, and immunity of the host, contributing to the host’s health [ 2 ]. Maintaining beneficial gut microbiota can prevent various metabolic diseases, including obesity, type 2 diabetes, non-alcohol hepatic steatosis, and Alzheimer’s disease [ 3 , 4 ]. Although the gut microbiome is not easily changed, environmental factors, such as diets, drugs, and physical activity, modulate the gut microbiota community [ 3 , 5 ].…”