The bright and the dark sides of L-carnitine supplementation: a systematic review

Figures & data

Fig. 1 Flowchart on the search and selection of articles included in the review

Table 1 Summary and results of the studies reviewed examining the LC supplementation

Fig. 2 The association between LC supplementation and the regulation of metabolic pathways involved in muscle protein balance. L-carnitine (LC); insulin-like growth factor-1 (IGF-1); phosphoinositide-3-kinase (PI3K); protein kinase B (Akt); mammalian target of rapamycin (mTOR); forkhead box O (FoxO); muscle-specific RING finger-1 (MuRF-1); muscle atrophy F-box (atrogin-1); increase (

); decrease (

); activation (

); inactivation (

)

WachterSVogtMKreisRBoeschCBiglerPHoppelerHKrahenbuhlSLong-term administration of L-carnitine to humans: effect on skeletal muscle carnitine content and physical performanceClin Chim Acta2002318 1–2 51 61 1:CAS:528:DC%2BD38XhslWjsb0%3D https://doi.org/10.1016/s0009-8981(01)00804-x 11880112

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LohningerASendicALitzlbauerEHofbauerRStaniekHBleskyDSchwieglhoferCEderMBergmullerHMascherD et al Endurance exercise training and L-carnitine supplementation stimulates gene expression in the blood and muscle cells in young athletes and middle aged subjectsMonatshefte Fur Chemie2005136 8 1425 1442 1:CAS:528:DC%2BD2MXmsFKltbw%3D https://doi.org/10.1007/s00706-005-0335-6

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ShannonCEGhasemiRGreenhaffPLStephensFBIncreasing skeletal muscle carnitine availability does not alter the adaptations to high-intensity interval trainingScand J Med Sci Sports201828 1 107 115 https://doi.org/10.1111/sms.12885 28345160

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Sawicka AK, Hartmane D, Lipinska P, Wojtowicz E, Lysiak-Szydlowska W, Olek RA. l-Carnitine Supplementation in Older Women. A Pilot Study on Aging Skeletal Muscle Mass and Function. Nutrients. 2018;10(2). https://doi.org/https://doi.org/10.3390/nu10020255.

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OlekRASamulakJJSawickaAKHartmaneDGrinbergaSPugovicsOLysiak-SzydlowskaWIncreased Trimethylamine N-oxide is not associated with oxidative stress markers in healthy aged womenOxidative Med Cell Longev20192019 6247169 1:CAS:528:DC%2BB3cXmsFansbg%3D https://doi.org/10.1155/2019/6247169

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BordoniLSawickaAKSzarmachAWinklewskiPJOlekRAGabbianelliRA pilot study on the effects of l-Carnitine and Trimethylamine-N-oxide on platelet mitochondrial DNA methylation and CVD biomarkers in aged womenInt J Mol Sci202021 3 1047 1:CAS:528:DC%2BB3cXhslGnu7nN https://doi.org/10.3390/ijms21031047

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