右側から上から見ると,糖分解による筋肉燃料利用
1Department of Integrative Biology, University of California, Berkeley, CA, USA. gbrooks@berkeley.edu.
Advances in experimental medicine and biology
|August 29, 2025
まとめ
エロビック状態で継続的に生成される乳酸は,重要なエネルギー源であり,グルコース生成の前駆体であり,シグナリング分子です. 新しく発見された食後の乳酸シャトル (PLS) は,腸から筋肉への炭水化物の代謝における中心的な役割を明らかにしています.
科学分野:
- 代謝生理学
- 細胞生物学
- 運動生理学
背景:
- 乳酸は,様々な細胞と組織によってエアロビック状態で継続的に生成されます.
- 乳酸はエネルギー基板,グルコーネオジェニック前駆体,シグナル分子を含む複数の役割を果たします.
- 乳酸シャトル (細胞対細胞,細胞内,アストロサイト対ニューロン,ペロキシソーマ,細胞対ミトコンドリア) は以前から確認されている.
研究 の 目的:
- 乳酸の全身代謝における役割を明らかにする.
- 新しく発見された食後の乳酸シャトル (PLS) を説明する.
- 食物摂取から組織利用までの炭水化物の流れを理解する.
主な方法:
- 筋肉,組織,全身代謝に関する現代的な研究のレビュー.
- 運動生理学の研究結果の分析
- 食事後の乳酸シャトルに関する最近の発見の統合
主要な成果:
- 乳酸の生産は空気の条件下で継続的なプロセスです.
- PLSは腸内 (腸内乳酸生成) と全身内 (肝臓および組織代謝) の2つの段階を含む.
- 炭水化物の流れは腸から始まり 筋肉で結束し 乳酸が重要な役割を果たします
結論:
- 乳酸は炭水化物の代謝において重要な中間物質である.
- PLSは,エネルギーホメオスタシスにおける乳酸の役割の統合性を強調しています.
- 乳酸のダイナミクスを理解することは,全身の代謝過程を理解するために不可欠です.
関連する概念動画
01:13Outcomes of Glycolysis
101.4K
Nearly all the energy used by cells comes from the bonds that make up complex organic compounds. These organic compounds are broken down into simpler molecules, such as glucose. As a result, cells extract energy from glucose over many chemical reactions—a process called cellular respiration.
Cellular respiration can occur aerobically (with oxygen) or anaerobically (without oxygen). In the presence of oxygen, cellular respiration starts with glycolysis and continues with pyruvate...
Cellular respiration can occur aerobically (with oxygen) or anaerobically (without oxygen). In the presence of oxygen, cellular respiration starts with glycolysis and continues with pyruvate...
101.4K
01:23Glycolysis
223
Glycolysis, the Embden-Meyerhof pathway, is a central metabolic pathway involved in glucose catabolism. It is highly conserved across most organisms, reflecting its fundamental role in cellular energy production. This process occurs in the cytoplasm and can function both in the presence and absence of oxygen, making it versatile for various organisms and environmental conditions.Stages of GlycolysisGlycolysis is a ten-step pathway that converts glucose into pyruvate, generating a net gain of...
223
00:56What is Glycolysis?
167.2K
Overview
Cells make energy by breaking down macromolecules. Cellular respiration is the biochemical process that converts "food energy" (from the chemical bonds of macromolecules) into chemical energy in the form of adenosine triphosphate (ATP). The first step of this tightly regulated and intricate process is glycolysis. The word glycolysis originates from the Latin glyco (sugar) and lysis (breakdown). Glycolysis serves two main intracellular functions: generating ATP and generating...
Cells make energy by breaking down macromolecules. Cellular respiration is the biochemical process that converts "food energy" (from the chemical bonds of macromolecules) into chemical energy in the form of adenosine triphosphate (ATP). The first step of this tightly regulated and intricate process is glycolysis. The word glycolysis originates from the Latin glyco (sugar) and lysis (breakdown). Glycolysis serves two main intracellular functions: generating ATP and generating...
167.2K
01:25Energy Supply for Muscle Contraction
3.7K
Skeletal muscle fibers have the unique ability to switch between rest and contraction states, using different sources of ATP for energy. The contraction cycle and Ca2+ transport back into the sarcoplasmic reticulum for relaxation require significant ATP. However, the ATP reserves in muscle fibers are limited and can only sustain contractions for a few seconds. Additional ATP production becomes necessary for prolonged contractions. As a result, muscle fibers generate ATP through various sources,...
3.7K
01:24Muscle Recovery and Fatigue
2.5K
Muscle fatigue refers to the decline in a muscle's ability to maintain the force of contraction after prolonged activity. It primarily stems from changes within muscle fibers. Even before experiencing muscle fatigue, one may feel tired and have the urge to stop the activity. This response, known as central fatigue, occurs due to changes in the central nervous system, namely the brain and spinal cord. While there is no single mechanism that induces fatigue, it may serve as a protective...
2.5K
01:20Fates of Pyruvate
9.0K
Pyruvate is the end product of glycolysis, where glucose is oxidized to pyruvate, simultaneously reducing NAD+ to NADH. Two molecules of ATP are also produced by substrate-level phosphorylation.
In aerobic organisms, pyruvate is metabolized via the citric acid cycle to produce reduced coenzymes NADH and FADH2. These coenzymes are then oxidized in the electron transport chain to produce ATP and, in the process, regenerate the NAD+ and FAD. As seen in some cell types and organisms, fermentation...
In aerobic organisms, pyruvate is metabolized via the citric acid cycle to produce reduced coenzymes NADH and FADH2. These coenzymes are then oxidized in the electron transport chain to produce ATP and, in the process, regenerate the NAD+ and FAD. As seen in some cell types and organisms, fermentation...
9.0K