悪液質のLカルニチンレビュー

悪液質に対するLカルニチンのレビュー論文を紹介します。

Robert Ringseis, Janine Keller, Klaus Eder. Mechanisms underlying the anti-wasting effect of l-carnitine supplementation under pathologic conditions: evidence from experimental and clinical studies. European Journal of Nutrition, DOI10.1007/s00394-013-0511-0

Lカルニチンの投与による窒素バランスの改善（蛋白合成増加もそくは蛋白分解減少）、アポトーシスの阻害、悪液質下での炎症反応の改善は、動物実験、ヒトでの臨床試験ともエビデンスがあります。酸化ストレスの緩和やミトコンドリア機能の改善は動物実験でのみ認めています。

Lカルニチン投与が悪液質に有効かどうかは、より大規模なRCTで検証されることが必要です。現時点では悪液質に対して試しに投与してもよいというところでしょうか。もちろん栄養療法や運動療法を併用した包括的対応の一環としてということになりますが。

Abstract

Purpose

Loss of skeletal muscle mass, also known as muscle wasting or muscle atrophy, is a common symptom of several chronic diseases, such as cancer and infectious diseases. Due to the strong negative impact of muscle loss on patient’s prognosis and quality of life, the development of efficacious treatment approaches to combat muscle wasting are of great importance. In order to evaluate the suitability of l-carnitine (LC) as an anti-wasting agent for clinical purposes the present review comprehensively summarizes the results from animal and clinical studies showing the effects of supplementation with LC or LC derivatives (acetyl-LC, propionyl-LC) on critical mechanisms involved in skeletal muscle loss under pathologic conditions, such as increased proteolysis, impaired protein synthesis, myonuclear apoptosis, inflammation, oxidative stress, and mitochondrial dysfunction.

Results

Evidence from both animal and clinical studies exists that LC supplementation causes an improved nitrogen balance either due to increased protein synthesis or reduced protein degradation, an inhibition of apoptosis and an abrogation of inflammatory processes under pathologic conditions. Furthermore, strong evidence has been provided, at least from animal studies, that LC supplementation prevents oxidative stress and ameliorates mitochondrial function, whereas results from a very low number of available clinical studies in this regard are inconclusive.

Conclusion

In conclusion, LC supplementation beneficially influences several critical mechanisms involved in pathologic skeletal muscle loss that may at least partially explain the anti-catabolic effects and the improvement of fatigue-related parameters following LC supplementation in patients with chronic diseases. However, more suitable clinical trials (double-blinded, randomized, placebo-controlled, large-scale) are necessary in order to establish LC supplementation as strategy for anti-wasting therapy.