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Functional differences between l- and d-carnitine in metabolic regulation evaluated using a low-carnitine Nile tilapia model

  • Jia-Min Li (a1), Ling-Yu Li (a1), Yu-Xue Zhang (a1), Zhe-Yue Jiang (a1), Samwel M. Limbu (a1) (a2), Fang Qiao (a1), Pascal Degrace (a3), Li-Qiao Chen (a1), Mei-Ling Zhang (a1) and Zhen-Yu Du (a1)...


l-Carnitine is essential for mitochondrial β-oxidation and has been used as a lipid-lowering feed additive in humans and farmed animals. d-Carnitine is an optical isomer of l-carnitine and dl-carnitine has been widely used in animal feeds. However, the functional differences between l- and d-carnitine are difficult to study because of the endogenous l-carnitine background. In the present study, we developed a low-carnitine Nile tilapia model by treating fish with a carnitine synthesis inhibitor, and used this model to investigate the functional differences between l- and d-carnitine in nutrient metabolism in fish. l- or d-carnitine (0·4 g/kg diet) was fed to the low-carnitine tilapia for 6 weeks. l-Carnitine feeding increased the acyl-carnitine concentration from 3522 to 10 822 ng/g and alleviated the lipid deposition from 15·89 to 11·97 % in the liver of low-carnitine tilapia. However, as compared with l-carnitine group, d-carnitine feeding reduced the acyl-carnitine concentration from 10 822 to 5482 ng/g, and increased lipid deposition from 11·97 to 20·21 % and the mRNA expression of the genes involved in β-oxidation and detoxification in the liver. d-Carnitine feeding also induced hepatic inflammation, oxidative stress and apoptosis. A metabolomic investigation further showed that d-carnitine feeding increased glycolysis, protein metabolism and activity of the tricarboxylic acid cycle and oxidative phosphorylation. Thus, l-carnitine can be physiologically utilised in fish, whereas d-carnitine is metabolised as a xenobiotic and induces lipotoxicity. d-Carnitine-fed fish demonstrates increases in peroxisomal β-oxidation, glycolysis and amino acid degradation to maintain energy homeostasis. Therefore, d-carnitine is not recommended for use in farmed animals.

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Corresponding author

*Corresponding author: Professor Z.-Y. Du, email


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1. Bremer, J (1983) Carnitine-metabolism and functions. Physiol Rev 63, 14201480.
2. Zammit, VA, Ramsay, RR, Bonomini, M, et al. (2009) Carnitine, mitochondrial function and therapy. Adv Drug Del Rev 61, 13531362.
3. Bieber, L (1988) Carnitine. Annu Rev Biochem 57, 261283.
4. Steiber, A, Kerner, J & Hoppel, CL (2004) Carnitine: a nutritional, biosynthetic, and functional perspective. Mol Aspects Med 25, 455473.
5. Tanphaichitr, V & Broquist, HP (1974) Site of carnitine biosynthesis in the rat. J Nutr 104, 16691673.
6. Pons, R & De Vivo, DC (1995) Primary and secondary carnitine deficiency syndromes. J Child Neurol 10, Suppl. 2, S8.
7. Scholte, HR, Pereira, RR, Jonge, PCD, et al. (1990) Primary carnitine deficiency. J Clin Chem Clin Biochem 28, 351.
8. Mingrone, G (2004) Carnitine in type 2 diabetes. Ann N Y Acad Sci 1033, 99107.
9. Stephens, FB, Constantin-Teodosiu, D & Greenhaff, PL (2007) New insights concerning the role of carnitine in the regulation of fuel metabolism in skeletal muscle. J Physiol 581, 431444.
10. Stephens, FB, Constantin-Teodosiu, D, Laithwaite, D, et al. (2006) An acute increase in skeletal muscle carnitine content alters fuel metabolism in resting human skeletal muscle. J Clin Endocrinol Metab 91, 50135018.
11. Harmeyer, J (2003) Use of L-carnitine additions in domestic animal feeds. Lohmann Info 28, 19.
12. Harpaz, S (2005) L-carnitine and its attributed functions in fish culture and nutrition—a review. Aquaculture 249, 321.
13. Vernez, L (2005) Analysis of carnitine and acylcaritines in biological fluids and application to a clinical study. PhD Thesis, University of Basel, Basel.
14. Sánchez-Hernández, L, Castro-Puyana, M, García-Ruiz, C, et al. (2010) Determination of l-and D-carnitine in dietary food supplements using capillary electrophoresis–tandem mass spectrometry. Food Chem 120, 921928.
15. Sánchez-Hernández, L, García-Ruiz, C, Crego, AL, et al. (2010) Sensitive determination of D-carnitine as enantiomeric impurity of levo-carnitine in pharmaceutical formulations by capillary electrophoresis–tandem mass spectrometry. J Pharm Biomed Anal 53, 12171223.
16. Liedtke, AJ, Nellis, SH & Whitesell, LF (1981) Effects of carnitine isomers on fatty acid metabolism in ischemic swine hearts. Circ Res 48, 859866.
17. Liedtke, AJ, Nellis, SH, Whitesell, LF, et al. (1982) Metabolic and mechanical effects using L-and D-carnitine in working swine hearts. Am J Physiol Heart C 243, H691H697.
18. Spasov, AA, Iezhitsa, IN, Pisarev, VB, et al. (2006) Changes in myocardium, skeletal muscle and liver of rats fed carnitine-deficient diet and treated with carnitine optical isomers. Morfologiia 129, 4852.
19. Paulson, DJ & Shug, AL (1981) Tissue specific depletion of L-carnitine in rat heart and skeletal muscle by D-carnitine. Life Sci 28, 29312938.
20. Spasov, AA & Iezhitsa, IN (2005) Stereopharmacology of carnitine. Rossiĭskii Fiziologicheskiĭ Zhurnal Imeni Imsechenova 91, 14691482.
21. Leichter, J, Ottem, A & Hahn, P (1987) Does carnitine have a role in fat absorption? Life Sci 41, 941944.
22. Arafa, HM (2009) Carnitine deficiency: a possible risk factor in paracetamol hepatotoxicity. Arch Toxicol 83, 139150.
23. Santulli, A & D’Amelio, V (1986) Effects of supplemental dietary carnitine on growth and lipid metabolism of hatchery-reared sea bass (Dicentrarchus labrax L.). Aquaculture 59, 177186.
24. Du, ZY, Liu, YJ, Tian, LX, et al. (2002) Effects of two different carnitine isomers on growth and body composition of hybrid Oreochromis nilotica ♀×Oreochromis aurea. J Fish China 26, 259264.
25. Wang, JT, Liu, YJ, Tian, LX, et al. (2005) Effect of dietary lipid level on growth performance, lipid deposition, hepatic lipogenesis in juvenile cobia (Rachycentron canadum). Aquaculture 249, 439447.
26. Du, ZY, Clouet, P, Huang, L, et al. (2008) Utilization of different dietary lipid sources at high level in herbivorous grass carp (Ctenopharyngodon idella): mechanism related to hepatic fatty acid oxidation. Aquacult Nutr 14, 7792.
27. Li, JM, Li, LY, Qin, X, et al. (2017) Systemic regulation of L-carnitine in nutritional metabolism in zebrafish, Danio rerio . Sci Rep 7, 40815.
28. Santulli, A & D’Amello, V (1986) The effects of carnitine on the growth of sea bass, Dicentrarchus labrax L., fry. J Fish Biol 28, 8186.
29. Tian, J, Leng, XJ, Li, XQ, et al. (2009) Effect of dietary carnitine on growth performance, body composition and lipid metabolism enzymes of grass carp, Ctenopharyngodon idella . J Fish China 33, 295302.
30. Ozorio, ROA (2009) Dietary L-carnitine supplementation to cultivated fish: a mini-review. Curr Nutr Food Sci 5, 4048.
31. Heinonen, OJ & Takala, J (1994) Moderate carnitine depletion and long-chain fatty acid oxidation, exercise capacity, and nitrogen balance in the rat. Pediatr Res 36, 288292.
32. Li, JM, Li, LY, Qin, X, et al. (2018) Inhibited carnitine synthesis causes systemic alteration of nutrient metabolism in zebrafish. Front Physiol 9, 509.
33. Simkhovich, BZ, Shutenko, ZV, Meirena, DV, et al. (1988) 3-(2,2,2-Trimethylhydrazinium) propionate (THP)--a novel γ-butyrobetaine hydroxylase inhibitor with cardioprotective properties. Biochem Pharmacol 37, 195202.
34. Pan, H, Li, LY, Li, JM, et al. (2017) Inhibited fatty acid β-oxidation impairs stress resistance ability in Nile tilapia (Oreochromis niloticus). Fish Shellfish Immunol 68, 500508.
35. Richard, G, Michaelle, R, Naoual, A, et al. (2012) A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs. BMC Genomics 13, 222.
36. Folch, J, Lees, M & Sloane, SGH (1957) A simple method for the isolation and purification of total lipides from animal tissues. J Biol Chem 226, 497509.
37. Lambert, P & Dehnel, PA (1974) Seasonal variations in biochemical composition during the reproductive cycle of the intertidal gastropod Thais lamellosa Gmelin (Gastropoda, Prosobranchia). Can J Zool 52, 305318.
38. Betancor, MB, Sprague, M, Sayanova, O, et al. (2015) Evaluation of a high-EPA oil from transgenic Camelina sativa in feeds for Atlantic salmon (Salmo salar L.): effects on tissue fatty acid composition, histology and gene expression. Aquaculture 444, 112.
39. Du, ZY, Ma, T, Lock, EJ, et al. (2011) Depot-dependent effects of adipose tissue explants on co-cultured hepatocytes. PLoS ONE 6, e20917.
40. He, AY, Ning, LJ, Chen, LQ, et al. (2015) Systemic adaptation of lipid metabolism in response to low- and high-fat diet in Nile tilapia (Oreochromis niloticus). Phys Rep 3, e12485.
41. Zhang, A, Zhou, X, Zhao, H, et al. (2017) Metabolomics and proteomics technologies to explore the herbal preparation affecting metabolic disorders using high resolution mass spectrometry. Mol Biosyst 13, 320329.
42. Torreele, E, Sluiszen, AvD, Verreth, J (1993) The effect of dietary L-carnitine on the growth performance in fingerlings of the African catfish (Clarias gariepinus) in relation to dietary lipid. Br J Nutr 69, 289299.
43. Yang, SD, Wen, YC, Liou, CH, et al. (2009) Influence of dietary L-carnitine on growth, biological traits and meat quality in Tilapia. Aquac Res 40, 13741382.
44. Twibell, RG & Brown, PB (2000) Effect of dietary carnitine on growth rates and body composition of hybrid striped bass (Morone saxatilis male × M. chrysops female). Aquaculture 187, 153161.
45. Chatzifotis, S, Takeuchi, T & Seikai, T (1995) The effect of dietary L-carnitine on growth performance and lipid composition in red sea bream fingerlings. Fish Sci 61, 10041008.
46. Zheng, JL, Luo, Z, Zhuo, MQ, et al. (2014) Dietary l-carnitine supplementation increases lipid deposition in the liver and muscle of yellow catfish (Pelteobagrus fulvidraco) through changes in lipid metabolism. Br J Nutr 112, 698708.
47. Selcuk, Z, Tiril, SU, Alagil, F, et al. (2010) Effects of dietary L-carnitine and chromium picolinate supplementations on performance and some serum parameters in rainbow trout (Oncorhynchus mykiss). Aquac Int 18, 213221.
48. Morand, R, Bouitbir, J, Felser, A, et al. (2014) Effect of carnitine, acetyl-, and propionylcarnitine supplementation on the body carnitine pool, skeletal muscle composition, and physical performance in mice. Eur J Nutr 53, 13131325.
49. Wächter, S, Vogt, M, Kreis, R, et al. (2002) Long-term administration of L-carnitine to humans: effect on skeletal muscle carnitine content and physical performance. Clin Chim Acta 318, 5161.
50. Ozório, RO, Uktoseja, JL, Huisman, EA, et al. (2001) Changes in fatty acid concentrations in tissues of African catfish, Clarias gariepinus Burchell, as a consequence of dietary carnitine, fat and lysine supplementation. Br J Nutr 86, 623636.
51. Ozório, R, Van Ginneken, V, Van den Thillart, G, et al. (2005) Dietary canitine maintains energy reserves and delays fatigue of exercised African catfish (Clarias gariepinus) fed high fat diets. Sci Agric 62, 208213.
52. Degrace, P, Demizieux, L, Gresti, J, et al. (2004) Fatty acid oxidation and related gene expression in heart depleted of carnitine by mildronate treatment in the rat. Mol Cell Biochem 258, 171182.
53. Mattern, HM & Hardin, C (2007) Vascular metabolic dysfunction and lipotoxicity. Physiol Res 56, 149.
54. Schaffer, JE (2003) Lipotoxicity: when tissues overeat. Curr Opin Lipidol 14, 281287.
55. Perez-Martinez, P, Perez-Jimenez, F & Lopez-Miranda, J (2010) n-3 PUFA and lipotoxicity. BBA-Mol Cell Biol L 1801, 362366.
56. Degrace, P, Demizieux, L, Du, ZY, et al. (2007) Regulation of lipid flux between liver and adipose tissue during transient hepatic steatosis in carnitine-depleted rats. J Biol Chem 282, 2081620826.
57. Van den Branden, C & Vamecq, J (2003) Metabolic regulation of peroxisomal and mitochondrial fatty acid oxidation. Adv Exp Med Biol 544, 307314.
58. Mannaerts, GP, Debeer, LJ, Thomas, J, et al. (1979) Mitochondrial and peroxisomal fatty acid oxidation in liver homogenates and isolated hepatocytes from control and clofibrate-treated rats. J Biol Chem 254, 45854595.
59. Tsoko, M, Beauseigneur, F, Gresti, J, et al. (1995) Enhancement of activities relative to fatty acid oxidation in the liver of rats depleted of L-carnitine by D-carnitine and a γ-butyrobetaine hydroxylase inhibitor. Biochem Pharmacol 49, 14031410.
60. Spaniol, M, Kaufmann, P, Beier, K, et al. (2003) Mechanisms of liver steatosis in rats with systemic carnitine deficiency due to treatment with trimethylhydraziniumpropionate. J Lipid Res 44, 144153.
61. Peschechera, A, Scalibastri, M, Russo, F, et al. (2005) Carnitine depletion in rat pups from mothers given mildronate: a model of carnitine deficiency in late fetal and neonatal life. Life Sci 77, 30783091.
62. Wicks, SE, Vandanmagsar, B, Haynie, KR, et al. (2015) Impaired mitochondrial fat oxidation induces adaptive remodeling of muscle metabolism. Proc Natl Acad Sci U S A 112, 33003309.
63. Henderson, RJ & Tocher, DR (1987) The lipid composition and biochemistry of freshwater fish. Prog Lipid Res 26, 281347.
64. Torstensen, BE, Lie, Ø & Frøyland, L (2000) Lipid metabolism and tissue composition in Atlantic salmon (Salmo salar L.)—effects of capelin oil, palm oil, and oleic acid-enriched sunflower oil as dietary lipid sources. Lipids 35, 653664.
65. Frøyland, L, Lie, Ø & Berge, R (2000) Mitochondrial and peroxisomal β-oxidation capacities in various tissues from Atlantic salmon Salmo salar . Aquacult Nutr 6, 8589.
66. Constantin-Teodosiu, D, Carlin, J, Cederblad, G, et al. (1991) Acetyl group accumulation and pyruvate dehydrogenase activity in human muscle during incremental exercise. Acta Physiol 143, 367372.
67. Eizadi, M, Bakhshi, S, Abrifam, P, et al. (2011) Carnitine, metabolism, supplementation and exercise performance. Ind J Fund Appl Life Sci 1, 376385.
68. Siliprandi, N, Di Lisa, F, Pieralisi, G, et al. (1990) Metabolic changes induced by maximal exercise in human subjects following L-carnitine administration. BBA-Gen Subjects 1034, 1721.
69. Brevetti, G, Chiariello, M, Ferulano, G, et al. (1988) Increases in walking distance in patients with peripheral vascular disease treated with L-carnitine: a double-blind, cross-over study. Circulation 77, 767773.
70. Vecchiet, L, Di Lisa, F, Pieralisi, G, et al. (1990) Influence of L-carnitine administration on maximal physical exercise. Eur J Appl Physiol Occup Physiol 61, 486490.
71. Brass, EP (2000) Supplemental carnitine and exercise. Am J Clin Nutr 72, 618s623s.
72. Karlic, H & Lohninger, A (2004) Supplementation of L-carnitine in athletes: does it make sense? Nutrition 20, 709715.
73. Wilson, R (1994) Utilization of dietary carbohydrate by fish. Aquaculture 124, 6780.
74. Polakof, S, Médale, F, Larroquet, L, et al. (2011) Regulation of de novo hepatic lipogenesis by insulin infusion in rainbow trout fed a high-carbohydrate diet. J Anim Sci 89, 30793088.
75. Borges, P, Valente, LM, Véron, V, et al. (2014) High dietary lipid level is associated with persistent hyperglycaemia and downregulation of muscle Akt-mTOR pathway in Senegalese sole (Solea senegalensis). PLOS ONE 9, e102196.
76. Tavecchio, M, Lisanti, S, Bennett, MJ, et al. (2015) Deletion of cyclophilin D impairs β-oxidation and promotes glucose metabolism. Sci Rep 5, 15981.
77. Trevisan, R, Nosadini, R, Avogaro, A, et al. (1986) Type I diabetes is characterized by insulin resistance not only with regard to glucose, but also to lipid and amino acid metabolism. J Clin Endocrinol Metab 62, 1155.
78. Solini, A, Bonora, E, Bonadonna, R, et al. (1997) Protein metabolism in human obesity: relationship with glucose and lipid metabolism and with visceral adipose tissue. J Clin Endocrinol Metab 82, 25522558.


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Functional differences between l- and d-carnitine in metabolic regulation evaluated using a low-carnitine Nile tilapia model

  • Jia-Min Li (a1), Ling-Yu Li (a1), Yu-Xue Zhang (a1), Zhe-Yue Jiang (a1), Samwel M. Limbu (a1) (a2), Fang Qiao (a1), Pascal Degrace (a3), Li-Qiao Chen (a1), Mei-Ling Zhang (a1) and Zhen-Yu Du (a1)...


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