The Ketogenic Diet is an Inducible Muscle Fat and Ketone Body Catabolism to Reduce Aging Sarcopenia

Editorial

The ketogenic diet is super high in fat (about 80% to 90% of your daily), super low in carbohydrates (up to 4% of your daily) and moderate in protein (6~8% of your daily) [1]. The most important component of the keto diet is a natural process called ketosis. When you cut back on carbs or just haven’t eaten in a while, your body looks for other energy sources to fill the void [2]. Fat is typically that source. When your blood sugar drops because you’re not feeding your body carbs, fat is released from your cells and floods the liver. The liver turns the fat into ketone bodies, which your body uses as its second choice for energy [3]. Muscle catabolism of ketone bodies in aging sarcopenia. Acetyl-CoA produced by the β-oxidation of liver tissue fatty acids can be converted into ketone bodies, including acetoacetate (30%), β-hydroxybutyrate (70%), and acetone. The utilization of β-hydroxybutyric acid is first catalyzed by β-hydroxybutyrate dehydrogenase, which is dehydrogenated to acetoacetic acid, and then converted into acetyl CoA for oxidation [4]. Normally, the amount of acetone produced is very small. Acetone is a volatile substance that can be exhaled through the lungs. The acetone content in the ketone body is also greatly increased, and it is discharged through the respiratory tract, producing a special “rotten apple smell”. Ketones are intermediate products produced by fatty acids in the catabolism of the liver. The formation of ketone bodies is based on acetyl-CoA produced by fatty acid β-oxidation, which is completed in liver mitochondria. Ketone bodies are utilized by extrahepatic tissues, such as muscle, through the conversion of β-hydroxybutyrate to acetoacetate and of acetoacetate to acetoacetyl- CoA [5]. The first step involves the reversal of the β-hydroxybutyrate dehydrogenase reaction, and the second step involves the action of acetoacetate: succinyl-CoA transferase [6]. Additionally, liver tissue lacks an enzyme system that utilizes ketone bodies, so ketones are transported through the bloodstream to extrahepatic tissues for oxidative utilization. Many tissues outside the liver have highly active enzymes that use ketone bodies, which can re-cleave ketone bodies into acetyl CoA, and completely decompose and oxidize them through the tricarboxylic acid cycle [7]. The physiological significance of ketone body generation, ketone body is soluble in water, small molecule, can be transported in the blood, and can also pass through the blood-brain barrier and the capillary wall of muscle and other tissues, which is a form of energy delivery from the liver to extrahepatic tissues, especially when long-term hunger, insufficient sugar supply or glucose utilization disorder, ketone body can replace glucose to become the main energy substance of brain and muscle tissue [8]. However, during starvation, ketogenic diet, and diabetes, ketone production also increases due to increased fat mobilization. This ensures that muscle have access to ketone body as a fuel source during ketogenic diet ketogenesis [9]. Some of these effects depend on ketone bodies. The use of non-carbohydrates as a source of energy during ketogenic diet ketogenesis so that the depletion of muscle glycogen stores is delayed [10]. If fat, for example, makes a greater contribution to a sarcopenia effort during the initial stages of muscle loss, more ketone body will be available for the later stages and muscle fatigue will be delayed.

Acknowledgment

None.

Conflict of Interest

None.

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