Preface

Metabolic diseases such as obesity and diabetes cause disruption of systemic energy metabolism and are major public health problems, affecting at least 2 billion people worldwide. The energy metabolism of the whole body is mainly regulated by skeletal muscle, liver, and brain. This book, entitled “Skeletal Muscle Health in Metabolic Disease”, aims to clarify organ and tissue alterations in metabolic diseases, such as obesity, diabetes, and fatty liver.

The book comprises six chapters. The first chapter gives a background of metabolic diseases that affect cellular mechanisms in muscle cells and muscle tissue, especially glucose metabolism in skeletal muscle.

The skeletal muscle and liver share functions as metabolic organs, contributing to systemic metabolic regulation through mutual cooperation. The second chapter discusses the latest findings on the crosstalk between metabolic dysfunction-associated steatotic liver disease (MASLD) and skeletal muscles, which starts and progresses in association with obesity and its associated systemic metabolic abnormalities.

The third chapter focuses on nutrition, especially carbohydrate metabolism. Lipids are stored in the body mainly in the form of triglycerides, whereas carbohydrates are primarily stored in the liver and skeletal muscles in the form of glycogen. Glycogen utilization has also been shown to increase during exercise. When glycogen is depleted, exercise performance is impaired. Therefore, carbohydrate metabolism is important for exercise and the maintenance of organ and tissue homeostasis.

The subsequent five and six chapters discuss muscle atrophy and weakness and cellular mechanisms in metabolic disease. Muscle oxidative stress has been implicated in lipid species composition in the development of type 2 diabetes. Therefore, the sixth chapter discusses the impact of metabolic disorders, such as obesity and type 2 diabetes, on the regulation of lipid species and oxidative stress.