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Caballero-García A, Noriega-González DC, Roche E, Drobnic F, Córdova A. Effects of L-Carnitine Intake on Exercise-Induced Muscle Damage and Oxidative Stress: A Narrative Scoping Review. Nutrients 2023; 15:nu15112587. [PMID: 37299549 DOI: 10.3390/nu15112587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/16/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023] Open
Abstract
Exercise-induced muscle damage results in decreased physical performance that is accompanied by an inflammatory response in muscle tissue. The inflammation process occurs with the infiltration of phagocytes (neutrophils and macrophages) that play a key role in the repair and regeneration of muscle tissue. In this context, high intensity or long-lasting exercise results in the breakdown of cell structures. The removal of cellular debris is performed by infiltrated phagocytes, but with the release of free radicals as collateral products. L-carnitine is a key metabolite in cellular energy metabolism, but at the same time, it exerts antioxidant actions in the neuromuscular system. L-carnitine eliminates reactive oxygen and nitrogen species that, in excess, alter DNA, lipids and proteins, disturbing cell function. Supplementation using L-carnitine results in an increase in serum L-carnitine levels that correlates positively with the decrease in cell alterations induced by oxidative stress situations, such as hypoxia. The present narrative scoping review focuses on the critical evaluation of the efficacy of L-carnitine supplementation on exercise-induced muscle damage, particularly in postexercise inflammatory and oxidative damage. Although both concepts appear associated, only in two studies were evaluated together. In addition, other studies explored the effect of L-carnitine in perception of fatigue and delayed onset of muscle soreness. In view of the studies analyzed and considering the role of L-carnitine in muscle bioenergetics and its antioxidant potential, this supplement could help in postexercise recovery. However, further studies are needed to conclusively clarify the mechanisms underlying these protective effects.
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Affiliation(s)
- Alberto Caballero-García
- Department of Anatomy and Radiology, Faculty of Health Sciences, GIR Physical Exercise and Aging, University of Valladolid, Campus Los Pajaritos, 42004 Soria, Spain
| | - David C Noriega-González
- Department of Surgery, Ophthalmology, Otorhinolaryngology and Physiotherapy, Faculty of Medicine, Hospital Clínico Universitario de Valladolid, 47003 Valladolid, Spain
| | - Enrique Roche
- Department of Applied Biology-Nutrition, Institute of Bioengineering, University Miguel Hernández, 03202 Elche, Spain
- Alicante Institute for Health and Biomedical Research (ISABIAL), 03010 Alicante, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III (ISCIII), 28029 Madrid, Spain
| | - Franchek Drobnic
- Medical Services Wolverhampton Wanderers FC, Wolverhampton WV3 9BF, UK
| | - Alfredo Córdova
- Biochemistry, Molecular Biology and Physiology, Faculty of Health Sciences, GIR Physical Exercise and Aging, University of Valladolid, Campus Duques de Soria, 42004 Soria, Spain
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Takashima H, Maruyama T, Abe M. Significance of Levocarnitine Treatment in Dialysis Patients. Nutrients 2021; 13:1219. [PMID: 33917145 PMCID: PMC8067828 DOI: 10.3390/nu13041219] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/01/2021] [Accepted: 04/04/2021] [Indexed: 01/04/2023] Open
Abstract
Carnitine is a naturally occurring amino acid derivative that is involved in the transport of long-chain fatty acids to the mitochondrial matrix. There, these substrates undergo β-oxidation, producing energy. The major sources of carnitine are dietary intake, although carnitine is also endogenously synthesized in the liver and kidney. However, in patients on dialysis, serum carnitine levels progressively fall due to restricted dietary intake and deprivation of endogenous synthesis in the kidney. Furthermore, serum-free carnitine is removed by hemodialysis treatment because the molecular weight of carnitine is small (161 Da) and its protein binding rates are very low. Therefore, the dialysis procedure is a major cause of carnitine deficiency in patients undergoing hemodialysis. This deficiency may contribute to several clinical disorders in such patients. Symptoms of dialysis-related carnitine deficiency include erythropoiesis-stimulating agent-resistant anemia, myopathy, muscle weakness, and intradialytic muscle cramps and hypotension. However, levocarnitine administration might replenish the free carnitine and help to increase carnitine levels in muscle. This article reviews the previous research into levocarnitine therapy in patients on maintenance dialysis for the treatment of renal anemia, cardiac dysfunction, dyslipidemia, and muscle and dialytic symptoms, and it examines the efficacy of the therapeutic approach and related issues.
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Affiliation(s)
| | | | - Masanori Abe
- Division of Nephrology, Hypertension and Endocrinology, Department of Internal Medicine, Nihon University School of Medicine, 30-1 Oyaguchi Kami-cho, Itabashi-ku, Tokyo 173-8610, Japan; (H.T.); (T.M.)
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3
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Abstract
Among the various metabolic abnormalities documented in dialysis patients are abnormalities related to the metabolism of fatty acids. Aberrant fatty-acid metabolism has been associated with the promotion of free-radical production, insulin resistance, and cellular apoptosis. These processes have been identified as important contributors to the morbidity experienced by dialysis patients. There is evidence that levocarnitine supplementation can modify the deleterious effects of defective fatty-acid metabolism. Patients receiving hemodialysis and, to a lesser degree, peritoneal dialysis have been shown to be carnitine deficient, as manifested by reduced levels of plasma free carnitine and an increase in the acyl:free carnitine ratio. Cardiac and skeletal muscles are particularly dependent on fatty-acid metabolism for the generation of energy. A number of clinical abnormalities have been correlated with a low plasma carnitine status in dialysis patients. Clinical trials have examined the efficacy of levocarnitine therapy in a number of conditions common in dialysis patients, including skeletal-muscle weakness and fatigue, cardiomyopathy, dialysis-related hypotension, hyperlipidemia, and anemia poorly responsive to recombinant human erythropoietin therapy (rHuEPO). This review examines the evidence for carnitine deficiency in patients requiring dialysis, and documents the results of relevant clinical trials of levocarnitine therapy in this population. Consensus recommendations by expert panels are summarized and contrasted with present guidelines for access to levocarnitine therapy by dialysis patients.
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Affiliation(s)
- Brian Schreiber
- Dialysis Care, Department of Medicine, Division of Nephrology, Medical College of Wisconsin, Milwaukee, WI, USA.
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Gimenes AC, Bravo DM, Nápolis LM, Mello MT, Oliveira ASB, Neder JA, Nery LE. Effect of L-carnitine on exercise performance in patients with mitochondrial myopathy. ACTA ACUST UNITED AC 2015; 48:354-62. [PMID: 25714882 PMCID: PMC4418367 DOI: 10.1590/1414-431x20143467] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 11/11/2014] [Indexed: 11/22/2022]
Abstract
Exercise intolerance due to impaired oxidative metabolism is a prominent symptom in
patients with mitochondrial myopathy (MM), but it is still uncertain whether
L-carnitine supplementation is beneficial for patients with MM. The aim of our study
was to investigate the effects of L-carnitine on exercise performance in MM. Twelve
MM subjects (mean age±SD=35.4±10.8 years) with chronic progressive external
ophthalmoplegia (CPEO) were first compared to 10 healthy controls (mean age±SD=29±7.8
years) before they were randomly assigned to receive L-carnitine supplementation (3
g/daily) or placebo in a double-blind crossover design. Clinical status, body
composition, respiratory function tests, peripheral muscle strength (isokinetic and
isometric torque) and cardiopulmonary exercise tests (incremental to peak exercise
and at 70% of maximal), constant work rate (CWR) exercise test, to the limit of
tolerance [Tlim]) were assessed after 2 months of L-carnitine/placebo administration.
Patients with MM presented with lower mean height, total body weight, fat-free mass,
and peripheral muscle strength compared to controls in the pre-test evaluation. After
L-carnitine supplementation, the patients with MM significantly improved their Tlim
(14±1.9 vs 11±1.4 min) and oxygen consumption (V˙O2) at CWR exercise, both at isotime (1151±115 vs
1049±104 mL/min) and at Tlim (1223±114 vs 1060±108 mL/min). These
results indicate that L-carnitine supplementation may improve aerobic capacity and
exercise tolerance during high-intensity CWRs in MM patients with CPEO.
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Affiliation(s)
- A C Gimenes
- Setor de Função Pulmonar e Fisiologia Clínica do Exercício, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - D M Bravo
- Setor de Função Pulmonar e Fisiologia Clínica do Exercício, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - L M Nápolis
- Setor de Função Pulmonar e Fisiologia Clínica do Exercício, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - M T Mello
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - A S B Oliveira
- Setor de Doenças Neuromusculares, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - J A Neder
- Setor de Função Pulmonar e Fisiologia Clínica do Exercício, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | - L E Nery
- Setor de Função Pulmonar e Fisiologia Clínica do Exercício, Universidade Federal de São Paulo, São Paulo, SP, Brasil
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D'Antona G, Nabavi SM, Micheletti P, Di Lorenzo A, Aquilani R, Nisoli E, Rondanelli M, Daglia M. Creatine, L-carnitine, and ω3 polyunsaturated fatty acid supplementation from healthy to diseased skeletal muscle. BIOMED RESEARCH INTERNATIONAL 2014; 2014:613890. [PMID: 25243159 PMCID: PMC4163371 DOI: 10.1155/2014/613890] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 07/19/2014] [Accepted: 08/06/2014] [Indexed: 12/22/2022]
Abstract
Myopathies are chronic degenerative pathologies that induce the deterioration of the structure and function of skeletal muscle. So far a definitive therapy has not yet been developed and the main aim of myopathy treatment is to slow the progression of the disease. Current nonpharmacological therapies include rehabilitation, ventilator assistance, and nutritional supplements, all of which aim to delay the onset of the disease and relieve its symptoms. Besides an adequate diet, nutritional supplements could play an important role in the treatment of myopathic patients. Here we review the most recent in vitro and in vivo studies investigating the role supplementation with creatine, L-carnitine, and ω3 PUFAs plays in myopathy treatment. Our results suggest that these dietary supplements could have beneficial effects; nevertheless continued studies are required before they could be recommended as a routine treatment in muscle diseases.
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Affiliation(s)
- Giuseppe D'Antona
- Department of Molecular Medicine and Laboratory for Motor Activities in Rare Diseases (LUSAMMR), University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Seyed Mohammad Nabavi
- Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, P.O. Box 19395-5487, Tehran, Iran
| | - Piero Micheletti
- Department of Experimental and Forensic Medicine, University of Pavia, Via Forlanini 2, 27100 Pavia, Italy
| | - Arianna Di Lorenzo
- Department of Drug Sciences, Medicinal Chemistry and Pharmaceutical Technology Section, University of Pavia, Via Taramelli 12, 27100 Pavia, Italy
| | - Roberto Aquilani
- Maugeri Foundation IRCCS, Montescano Scientific Institute, Via Per Montescano 31, 27040 Montescano, Italy
| | - Enzo Nisoli
- Center for Study and Research on Obesity, Department of Medical Biotechnology and Translational Medicine, University of Milan, Via Vanvitelli 32, 20129 Milan, Italy
| | - Mariangela Rondanelli
- Human Nutrition Section, Health Sciences Department, University of Pavia, Azienda di Servizi alla Persona, Via Emilia 12, 27100 Pavia, Italy
| | - Maria Daglia
- Department of Drug Sciences, Medicinal Chemistry and Pharmaceutical Technology Section, University of Pavia, Via Taramelli 12, 27100 Pavia, Italy
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Tayebi Khosroshahi H, Habibi Asl B, Habibzadeh A, Chaichi P, Ghanbarpour A, Hossein Badie A. Comparison of vitamin e and L-carnitine, separately or in combination in patients with intradialytic complications. Nephrourol Mon 2013; 5:862-5. [PMID: 24350082 PMCID: PMC3842554 DOI: 10.5812/numonthly.10670] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2013] [Revised: 02/24/2013] [Accepted: 03/03/2013] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND The most common complications during dialysis are hypotension and muscle cramps. There are many strategies to prevent and treat these complications. OBJECTIVES The aim of this study is to evaluate effects of vitamin E and L-carnitine supplementation alone and in combination on intradialytic complications. PATIENTS AND METHODS In a prospective study, 20 patients with end stage renal disease on chronic hemodialysis that had intradialytic complications such as hypotension, muscle cramp, nausea, vomiting and headache were studied. These patients were studied in four 45 day periods, beginning with no treatment (step 1), receiving vitamin E (200 IU/d) (step 2), receiving L-carnitine (500 mg/d) (step 3) and their combination (step 4). Intradialytic complications were recorded in each step and compared between treatments. RESULTS All three treatments significantly reduced frequency of muscle cramps in comparison to baseline values. Vitamin E alone and in combination with L-carnitine reduced the frequency of muscle cramps more effectively. Hypotension was significantly lower in combination therapy in comparison to baseline values and vitamin E treatment. CONCLUSIONS Vitamin E and L-carnitine both have comparative effects on intradialytic complications. As the combination use of vitamin E and L-carnitine could more effectively reduce the intradialytic complications, it is recommended for daily use in hemodialysis patients.
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Affiliation(s)
- Hamid Tayebi Khosroshahi
- Department of Nephrology, Liver and Gastrointestinal Disease Research Center, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Bohlul Habibi Asl
- Department of Pharmacology, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Afshin Habibzadeh
- Department of Cardiology, Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Parastoo Chaichi
- Medical Philosophy and History Research Center, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Amin Ghanbarpour
- Department of Cardiology, Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Amir Hossein Badie
- Medical Philosophy and History Research Center, Tabriz University of Medical Sciences, Tabriz, IR Iran
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7
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Ringseis R, Keller J, Eder K. Mechanisms underlying the anti-wasting effect of l-carnitine supplementation under pathologic conditions: evidence from experimental and clinical studies. Eur J Nutr 2013; 52:1421-42. [DOI: 10.1007/s00394-013-0511-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 03/03/2013] [Indexed: 01/17/2023]
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Beghi E, Pupillo E, Bonito V, Buzzi P, Caponnetto C, Chiò A, Corbo M, Giannini F, Inghilleri M, Bella VL, Logroscino G, Lorusso L, Lunetta C, Mazzini L, Messina P, Mora G, Perini M, Quadrelli ML, Silani V, Simone IL, Tremolizzo L. Randomized double-blind placebo-controlled trial of acetyl-L-carnitine for ALS. Amyotroph Lateral Scler Frontotemporal Degener 2013; 14:397-405. [DOI: 10.3109/21678421.2013.764568] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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9
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Abstract
Carnitine, 3-hydroxy-4-trimethylaminobutyrate, a small, water soluble molecule that is essential for mitochondrial fatty acid oxidation, is significantly reduced in hemodialysis patients. Uremia-induced carnitine deficiency, which is magnified by dialysis, is associated with symptoms or clinical problems such as anemia hyporesponsive to erythropoietin, cardiovascular diseases, and muscle weakness. This review examines studies dealing with the different clinical aspects of chronic renal failure patients in which carnitine deficiency may play a role and has also examined the studies, which have evaluated the effect of carnitine deficiency treatment. The reports reviewed in this study, including those more recent from our laboratory, have provided data suggesting that chronic renal failure and particularly hemodialysis patients can benefit from carnitine treatment in particular for renal anemia, insulin sensitivity, and protein catabolism. On the other hand, the heterogeneous clinical response to carnitine therapy in dialysis patients, reported by other studies, and the lack of large-scale randomized trials are the rationale for the reluctance regarding a widespread use of carnitine supplements in dialysis patients. Well-designed randomized clinical trials are therefore required to fully address the potentially important carnitine treatment in dialysis patients.
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Affiliation(s)
- Lorenzo A Calò
- Department of Medicine, Clinica Medica 4, University of Padova, Padova, Italy.
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10
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Silvério R, Laviano A, Rossi Fanelli F, Seelaender M. l-carnitine and cancer cachexia: Clinical and experimental aspects. J Cachexia Sarcopenia Muscle 2011; 2:37-44. [PMID: 21475677 PMCID: PMC3063878 DOI: 10.1007/s13539-011-0017-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 01/06/2011] [Indexed: 12/23/2022] Open
Abstract
Cancer cachexia is a multifaceted syndrome characterized, among many symptoms, by extensive muscle wasting. Chronic systemic inflammation, partly triggered and sustained by cytokines, as well as increased oxidative stress contributes to the pathogenesis of this complex metabolic disorder. l-carnitine plays a central role in the metabolism of fatty acids and shows important antioxidant and anti-inflammatory properties. Systemic carnitine depletion has been described in several diseases, and it is characterized by fatigue, muscle weakness, and decreased tolerance to metabolic stress. In cachectic cancer patients, low serum carnitine levels have been reported, and this change has been suggested to play an important contributory role in the development of cachexia. Based on these data, carnitine supplementation has been tested in preliminary studies concerning human cachexia, resulting in improved fatigue and quality of life. We present here a review of clinical and experimental evidence regarding the use of carnitine supplementation in the management of cancer cachexia.
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Affiliation(s)
- Renata Silvério
- Cancer Metabolism Research Group, Institute of Biomedical Sciences, Department of Cell and Developmental Biology University of São Paulo Av. Prof. Lineu Prestes, 1524 lab 434 CEP 08800-090 São Paulo SP
| | | | | | - Marília Seelaender
- Cancer Metabolism Research Group, Institute of Biomedical Sciences, Department of Cell and Developmental Biology University of São Paulo Av. Prof. Lineu Prestes, 1524 lab 434 CEP 08800-090 São Paulo SP
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11
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Karsidag T, Asensio JA, Kabukcuoglu F, Tuzun S. Preliminary study comparing the effects of locally and systemically applied L-carnitine on the healing of full-thickness skin defects. Scand J Surg 2010; 99:147-52. [PMID: 21044932 DOI: 10.1177/145749691009900309] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND AIMS L-carnitine as an endogenous cofactor has a role in the regulation of energy flow between different oxidative sources. The purpose of this study is to investigate that the clinical and histopathologic effects of L-carnitine locally and systemically on secondary healing in wounds of full thickness defects. We also measured the effects of L-carnitine on wound tensile strength as mechanical. MATERIAL AND METHODS sixty adult male Sprague-Dawley rats were divided into three groups randomly; group 1 (control group, n = 20), group 2 (local experimental group, n = 20), group 3 (systemic experimental group, n = 20). Group 1 was not given any pharmacologic agents. L-carnitine was administered locally in the group 2, and systemically in group 3 for a total of 14 days. The healing days of all groups were recorded. On the 7th, 10th,14th and 21st postoperative days, biopsy specimens, including tissue samples both from healing wound sites and sur-rounding healthy skin were evaluated for neovascularization, inflammation, the amount of collagen deposit, fibroblast migration and re-epithelization. Tensile strength was measured in the samples which completed healing on the 30th day. The results were evaluated by nonparametric Kruskall-Wallis test followed by Mann Whitney-U test. RESULTS the mean clinical healing days were 18.25 days, 16.5 days, 15 days for the control group, local experimental and systemic group, respectively. The differences between groups were statistically significant (p < 0.005). Mean tensile strength values were 762.10 centinewton (cN), 801.69 cN and 786.13 cN for the control group, local experimental group and systemic experimental group, respectively. There were no statistically significant differences between groups (p > 0.05). There was no statistically significant difference in the histopathologic ex-amination on the 7th, 10th, 14th and 21st days in the neovascularization, inflammation and fibroblast migration. Collagen deposit was most prevalent in the systemic experimental group and was least in the control group. Complete wound closure rate was observed on the 7th day in the systemic administration group, on the 10th day in local administration group and on the 14th day in the control group. Re-epithelization thickness in the systemic carnitine group was more than the other groups. CONCLUSIONS L-carnitine administered locally or systemically has positive effects on wound healing rate and tensile strength in rats.
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Affiliation(s)
- T Karsidag
- General Surgery Department, Haseki Education and Research Hospital, Istanbul, Turkey.
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Wilson ADH, Hart A, Wiberg M, Terenghi G. Acetyl-l-carnitine increases nerve regeneration and target organ reinnervation - a morphological study. J Plast Reconstr Aesthet Surg 2009; 63:1186-95. [PMID: 19664977 DOI: 10.1016/j.bjps.2009.05.039] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Revised: 05/04/2009] [Accepted: 05/21/2009] [Indexed: 11/19/2022]
Abstract
Peripheral nerve injury frequently results in functional morbidity since standard management fails to adequately address many of the neurobiological hurdles to optimal regeneration. Neuronal survival and regeneration are neurotrophin dependent and require increased aerobic capacity. Acetyl-l-carnitine (ALCAR) facilitates this need and prevents neuronal loss. ALCAR is clinically safe and is shown here to significantly improve nerve regeneration and target organ reinnervation. Two groups of five rats underwent sciatic nerve division followed by immediate repair. One group received parenteral ALCAR (50mg/kg/day) from time of operation until termination at 12 weeks. A 'sham treatment' group received normal saline. A third group was left unoperated and did not receive any treatment. A segment of nerve was harvested between 5mm proximal and 10mm distal to the repair in operated groups, and at the corresponding level in the unoperated group. Mean axonal count in normal, non-axotomised nerve was 14,720 (SD 2378). That of the saline group (17,217 SD 1808) was not significantly different from normal nerve (P=0.0985). Mean number of myelinated axons in the ALCAR group (24,460 SD 3750) was significantly greater than both sham group (P<0.01) and normal nerve (P=0.0012). Mean myelin thickness in the saline treated group (0.408 microm SD 0.067 microm) was less than normal nerve (0.770 microm SD 0.143 microm) (P<0.001). Mean myelin thickness in the ALCAR group (0.627 microm SD 0.052 microm) was greater than the sham (saline) group (P<0.01) and not statistically different from normal nerve (P=0.07). ALCAR increased dermal PGP9.5 staining by 210% compared to sham treatment (P<0.0001) and significantly reduced the mean percentage weight loss in gastrocnemius muscle (ALCAR group 0.203% vs. 0.312% in sham group P=0.015). ALCAR not only increases the number of regenerating nerve fibres but also morphologically improves the quality of regeneration and target organ reinnervation. Adjuvant ALCAR treatment may improve both sensory and motor outcomes and merits further investigation.
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Affiliation(s)
- Andrew D H Wilson
- Blond McIndoe Research Laboratories, Tissue Injury and Repair Group, University of Manchester, Room 3.106 Stopford Building, Oxford Road, Manchester M13 9PT, UK.
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Sabry AA, Ghaith O, Medhat T, George SK, Elshafey EE. Is there a Role for Oral L-Carnitine Therapy in Anemia and Cardiac Dysfunction Management in Egyptian Patients on Maintenance Hemodialysis? ELECTRONIC JOURNAL OF GENERAL MEDICINE 2009. [DOI: 10.29333/ejgm/82642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Abstract
BACKGROUND Uremia may be associated with various neurologic manifestations, particularly a polyneuropathy, but also with focal neuropathies such as carpal tunnel syndrome and shunt-related neuropathies. Myopathies can also be caused by uremia and its metabolic disarrangements. REVIEW SUMMARY This article reviews the clinical presentation, pathogenesis, and treatment of uremic polyneuropathy, focal neuropathies, and uremic myopathies. CONCLUSION Recognizing the presentation and pathogenesis of uremic polyneuropathies, mononeuropathies, and myopathies are important for their prevention and for proper management.
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Affiliation(s)
- Kefah Al-Hayk
- Department of Neurology, College of Medicine, University of Tennessee, Memphis, Tennessee, USA
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16
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Abstract
L-carnitine plays an essential role in the beta-oxidation of fatty acids by catalyzing their transport into the mitochondrial matrix. The kidney maintains plasma free L-carnitine levels in the homeostatic range by selective saturable tubular reabsorption. The preferential retention of free L-carnitine over acyl-L-carnitines by the kidney is lost in patients with end-stage renal disease (ESRD). Loss of renal parenchyma as a site of carnitine synthesis, as well as nonselective clearance of L-carnitine by the dialysis procedure lead to dialysis-related carnitine deficiency. Numerous studies investigating whether L-carnitine supplementation will alleviate several dialysis-related symptoms, such as intradialytic hypotension, heart failure, muscle weakness, low exercise capacity, and anemia, have reported conflicting results. Many of these studies suffer from a lack of randomization and control groups, heterogeneity in the administration of L-carnitine, and nonstandardized measures of symptom improvement. More data exist to support the use of L-carnitine in selected anemic dialysis patients with very large erythropoietin requirements in whom extensive examination for reversible causes of anemia was unrevealing.
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Affiliation(s)
- S Susan Hedayati
- Department of Medicine, Division of Nephrology, Veterans Affairs North Texas Health Care System, Dallas, Texas 75216-7167, USA.
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Abstract
A carnitina, uma amina quaternária (3-hidroxi-4-N-trimetilamino-butirato), é sintetizada no organismo (fígado, rins e cérebro) a partir de dois aminoácidos essenciais: lisina e metionina, exigindo para sua síntese a presença de ferro, ácido ascórbico, niacina e vitamina B6. Tem função fundamental na geração de energia pela célula, pois age nas reações transferidoras de ácidos graxos livres do citosol para mitocôndrias, facilitando sua oxidação e geração de adenosina Trifosfato. A concentração orgânica de carnitina é resultado de processos metabólicos - como ingestão, biossíntese, transporte dentro e fora dos tecidos e excreção - que, quando alterados em função de diversas doenças, levam a um estado carencial de carnitina com prejuízos relacionados ao metabolismo de lipídeos. A suplementação de L-carnitina pode aumentar o fluxo sangüíneo aos músculos devido também ao seu efeito vasodilatador e antioxidante, reduzindo algumas complicações de doenças isquêmicas, como a doença arterial coronariana, e as conseqüências da neuropatia diabética. Por esse motivo, o objetivo do presente trabalho foi descrever possíveis benefícios da suplementação de carnitina nos indivíduos com necessidades especiais e susceptíveis a carências de carnitina, como os portadores de doenças renais, neuropatia diabética, síndrome da imunodefeciência adquirida e doenças cardiovasculares.
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Calvani M, Benatti P, Mancinelli A, D'Iddio S, Giordano V, Koverech A, Amato A, Brass EP. Carnitine replacement in end-stage renal disease and hemodialysis. Ann N Y Acad Sci 2005; 1033:52-66. [PMID: 15591003 DOI: 10.1196/annals.1320.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In patients with chronic renal failure, not yet undergoing hemodialysis (HD), plasma acylcarnitines accumulate in part due to a decreased renal clearance of esterified carnitine moieties. In these patients, a high acylcarnitine/free-carnitine ratio is usually found in plasma. Patients undergoing maintenance HD, usually present with plasma carnitine insufficiency, due to accumulation of metabolic intermediates combined with impaired carnitine biosynthesis, reduced protein intake and increased removal via HD. Plasma carnitine concentrations rapidly decrease to 40% of baseline level during the dialysis session, with a slow restoration of the carnitine concentration during the interdialytic period, mainly from organs of storage (skeletal muscle). Dietary intake also plays an important role in carnitine homeostasis of HD patients since the prevalence of malnutrition ranges from 18% to 75% of these cases. This could differentially affect various body compartments, with clinical consequences such as impaired muscle function, decreased wound healing, altered ventilatory response, and abnormal immune function. Repeated hemodialytic treatments are associated with decreased carnitine stores in skeletal muscle. The administration of intravenous L-carnitine (LC) postdialysis replenishes the free carnitine removed from the blood and contributes to replenishment of muscle carnitine content. LC supplementation in selected uremic patients may yield clinical benefits by ameliorating several conditions, such as erythropoietin-resistant anemia, decreased cardiac performance, intradialytic hypotension, muscle symptoms, as well as impaired exercise and functional capacities. Furthermore, LC may positively influence the nutritional status of HD patients by promoting a positive protein balance, and by reducing insulin resistance and chronic inflammation, possibly through an effect on leptin resistance.
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Savica V, Calvani M, Benatti P, Santoro D, Monardo P, Peluso G, Bellinghieri G. Carnitine system in uremic patients: Molecular and clinical aspects. Semin Nephrol 2004; 24:464-8. [PMID: 15490412 DOI: 10.1016/j.semnephrol.2004.06.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Carnitine is a small water-soluble molecule that is present in almost all animal species. It plays an indispensable role in fatty acid metabolism, where it is involved in the transport of activated fatty acids between different cellular compartments. Uremic patients, as well as patients with chronic renal failure, appear to have abnormal renal handling of carnitine leading to dyslipidemia, lethargy, muscular weakness, hypotension, cardiac dysfunction and arrhythmias, and recurrent cramps. It often is difficult to distinguish these symptoms from similar ones related to uremia and dialysis. Many investigators have advocated L-carnitine supplementation in an attempt to alleviate carnitine deficiencies, and good results from this therapy have been reported. Moreover, several studies have shown that L-carnitine supplementation improves the response to erythropoietin. Chronic inflammation is another particular aspect affecting these patients. Anti-inflammatory properties of L-carnitine in hemodialysis patients have been shown by our group. Treatment with L-carnitine (20 mg/kg, given intravenously at the end of each dialysis session for 6 mo), significantly decreased serum C-reactive protein (CRP) levels, a proinflammatory cytokine known to inhibit erythropoiesis. Moreover, data from published literature are indicative of L-carnitine modulation of the immune system by the activation of glucocorticoid receptors and the modulation of the transcription of glucocorticoid-responsive genes. Our study showed that in these patients, treatment with L-carnitine has been able to improve their body mass index, likely by promoting a positive protein balance. This aspect is strictly correlated with the status of insulin resistance, which is well described in patients with renal diseases. Many studies showed that carnitine allowed mitochondrial fatty acid usage to link to the rate of glucose usage, thus improving insulin resistance. In conclusion, clinical beneficial effects of L-carnitine treatment on patients suffering from renal diseases are supported by molecular evidence involving both inflammatory and metabolic aspects of the disease.
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Abstract
Among the homeostatic processes controlling the endogenous L-carnitine pool in humans, the kidney has a vital role through extensive and adaptive tubular reabsorption. Kidney disease can lead to disturbances in L-carnitine homeostasis, and long-term hemodialysis therapy can lead to a significant reduction in plasma and tissue L-carnitine levels and an increase in the ratio of acyl-L-carnitine to free L-carnitine. These alterations may interfere with the oxidation of fatty acids and removal from tissues of unwanted short-chain acyl groups. A dialysis-related carnitine disorder (DCD) arises when these biochemical abnormalities exist in association with such clinical symptoms as muscle weakness, cardiomyopathy, intradialytic hypotension, or anemia that is resistant to erythropoietin therapy. Exogenous L-carnitine, administered intravenously, is approved for the treatment of secondary carnitine deficiency caused by long-term hemodialysis. Although intravenous administration of 20-mg/kg doses at the end of each hemodialysis session leads to supraphysiological levels of the compound in plasma, these levels do not appear to be associated with adverse effects. Because more than 99% of the body's carnitine pool is located outside of plasma, supraphysiological plasma levels appear to be required to ensure that depleted muscle stores can be replenished. Although oral L-carnitine has been used for the treatment of DCD, the bioavailability of oral L-carnitine is low (<15%) in healthy subjects and unknown in patients with end-stage renal disease. Moreover, gastrointestinal degradation of L-carnitine to trimethylamine and other compounds might limit the usefulness of long-term oral L-carnitine administration in this patient group.
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Affiliation(s)
- Allan Evans
- Centre for Pharmaceutical Research, School of Pharmaceutical, Molecular and Biomedical Sciences, University of South Australia, Adelaide, South Australia.
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21
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Miller B, Ahmad S. A review of the impact of L-carnitine therapy on patient functionality in maintenance hemodialysis. Am J Kidney Dis 2003; 41:S44-8. [PMID: 12751053 DOI: 10.1016/s0272-6386(03)00116-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Goals of maintenance hemodialysis therapy include not only the preservation of an individual patient's life in the presence of kidney failure, but also restoration of optimal quality of life. Although many conceptual and method problems are associated with the definition and assessment of quality of life in the chronically ill, there is broad agreement that patient quality of life is related to physical function and well-being. Evidence exists that despite advances in dialysis therapy, a high percentage of patients on maintenance dialysis therapy report chronic psychological symptoms, impaired activities of daily living and social function, and incomplete occupational rehabilitation that impair their functionality. This article reviews the impact of L-carnitine therapy on several dimensions of functionality in maintenance hemodialysis patients.
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Affiliation(s)
- Brent Miller
- Barnes Jewish Dialysis Center, St Louis, MO 63108, USA.
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22
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Abstract
Carnitine, gamma-trimethyl-beta-hydroxybutyrobetaine, is a small molecule widely present in all cells from prokaryotic to eukaryotic. It is an important element in the beta-oxidation of fatty acids. A lack of carnitine in hemodialysis patients is caused by insufficient carnitine synthesis and particularly by the loss through dialytic membranes, leading in some patients to carnitine depletion with a relative increase of esterified forms. The authors found a decrease in plasma-triglyceride and increase of high-density lipoprotein cholesterol (HDL-Chol) in dialysis patients during carnitine treatment. Many studies have shown that L-carnitine supplementation leads to improvements in several complications seen in uremic patients, including cardiac complications, impaired exercise and functional capacities, muscle symptoms, increased symptomatic intradialytic hypotension, and erythropoietin-resistant anemia, normalizing the reduced carnitine palmitoyl transferase activity in red cells. In addition, carnitine supplementation may improve protein metabolism and insulin resistance. Recently, carnitine supplementation has been approved by the US Food and Drug Administration not only for the treatment, but also for the prevention of carnitine depletion in dialysis patients. Regular carnitine supplementation in hemodialysis patients can improve their lipid metabolism, protein nutrition, antioxidant status, and anemia requiring large doses of erythropoietin, It also may reduce the incidence of intradialytic muscle cramps, hypotension, asthenia, muscle weakness, and cardiomyopathy.
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Matera M, Bellinghieri G, Costantino G, Santoro D, Calvani M, Savica V. History of L-carnitine: implications for renal disease. J Ren Nutr 2003; 13:2-14. [PMID: 12563618 DOI: 10.1053/jren.2003.50010] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
L-carnitine (LC) plays an essential metabolic role that consists in transferring the long chain fatty acids (LCFAs) through the mitochondrial barrier, thus allowing their energy-yielding oxidation. Other functions of LC are protection of membrane structures, stabilizing a physiologic coenzyme-A (CoA)-sulfate hydrate/acetyl-CoA ratio, and reduction of lactate production. On the other hand, numerous observations have stressed the carnitine ability of influencing, in several ways, the control mechanisms of the vital cell cycle. Much evidence suggests that apoptosis activated by palmitate or stearate addition to cultured cells is correlated with de novo ceramide synthesis. Investigations in vitro strongly support that LC is able to inhibit the death planned, most likely by preventing sphingomyelin breakdown and consequent ceramide synthesis; this effect seems to be specific for acidic sphingomyelinase. The reduction of ceramide generation and the increase in the serum levels of insulin-like growth factor (IGF)-1, could represent 2 important mechanisms underlying the observed antiapoptotic effects of acetyl-LC. Primary carnitine deficiency is an uncommon inherited disorder, related to functional anomalies in a specific organic cation/carnitine transporter (hOCTN2). These conditions have been classified as either systemic or myopathic. Secondary forms also are recognized. These are present in patients with renal tubular disorders, in which excretion of carnitine may be excessive, and in patients on hemodialysis. A lack of carnitine in hemodialysis patients is caused by insufficient carnitine synthesis and particularly by the loss through dialytic membranes, leading, in some patients, to carnitine depletion with a relative increase in esterified forms. Many studies have shown that LC supplementation leads to improvements in several complications seen in uremic patients, including cardiac complications, impaired exercise and functional capacities, muscle symptoms, increased symptomatic intradialytic hypotension, and erythropoietin-resistant anemia, normalizing the reduced carnitine palmitoyl transferase activity in red cells.
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Affiliation(s)
- Mario Matera
- Department of Pharmacology 2, Medical Faculty, University of Catania, Italy
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Rivero JLL, Sporleder HP, Quiroz-Rothe E, Vervuert I, Coenen M, Harmeyer J. Oral L-carnitine combined with training promotes changes in skeletal muscle. Equine Vet J 2002:269-74. [PMID: 12405699 DOI: 10.1111/j.2042-3306.2002.tb05431.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The purpose of this study was to determine whether oral L-carnitine supplementation enhances the responses of skeletal muscle to training in seven 2-year-old Standardbreds. Four horses were supplemented with 10 g/day L-carnitine for 10 weeks and 3 horses served as controls. All horses were exercised regularly every second day on a treadmill for 5 weeks (training period) and housed in individual boxes for 5 additional weeks (detraining period). The training period consisted of 8 high- and 8 low-speed exercises carried out in alternating sequence. Gluteus medius muscle biopsies were taken at Weeks 0 (pretraining), 5 (post-training) and 10 (detraining). Muscular adaptations to training were observed mainly in the L-carnitine-supplemented horses and included an increase in the percentage of type IIA fibres (delta35%, P<0.05), atrophy of type I fibres (delta24%, P<0.01), a rise in the capillary-to-fibre ratio (delta40%, P<0.01) and an increase in the quantitative reaction of periodic acid Schiff stain (delta11%, P<0.05), used as an indicator of intrafibre glycogen content. After detraining, most of these adaptations reverted towards the pretraining situation. Therefore, exogenous carnitine has an additive effect on muscular responses to training and this should be favourable to improve athletic performance. Nevertheless, further studies are necessary to show whether muscle carnitine content is a limiting factor for fatty acid oxidation.
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Affiliation(s)
- J L L Rivero
- Department of Anatomy, University of Cordoba, Spain
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25
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Wächter S, Vogt M, Kreis R, Boesch C, Bigler P, Hoppeler H, Krähenbühl S. Long-term administration of L-carnitine to humans: effect on skeletal muscle carnitine content and physical performance. Clin Chim Acta 2002; 318:51-61. [PMID: 11880112 DOI: 10.1016/s0009-8981(01)00804-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Long-term administration of high oral doses of L-carnitine on the skeletal muscle composition and the physical performance has not been studied in humans. METHODS Eight healthy male adults were treated with 2 x 2 g of L-carnitine per day for 3 months. Muscle biopsies and exercise tests were performed before, immediately after, and 2 months after the treatment. Exercise tests were performed using a bicycle ergometer for 10 min at 20%, 40%, and 60% of the individual maximal workload (P(max)), respectively, until exhaustion. RESULTS There were no significant differences between V(O(2)max), RER(max), and P(max) between the three time points investigated. At submaximal intensities, the only difference to the pretreatment values was a 5% increase in V(O(2)) at 20% and 40% of P(max) 2 months after the cessation of the treatment. The total carnitine content in the skeletal muscle was 4.10 +/- 0.82 micromol/g before, 4.79 +/- 1.19 micromol/g immediately after, and 4.19 +/- 0.61 micromol/g wet weight 2 months after the treatment (no significant difference). Activities of the two mitochondrial enzymes citrate synthase and cytochrome oxidase, as well as the skeletal muscle fiber composition also remained unaffected by the administration of L-carnitine. CONCLUSIONS Long-term oral treatment of healthy adults with L-carnitine is not associated with a significant increase in the muscle carnitine content, mitochondrial proliferation, or physical performance. Beneficial effects of the long-term treatment with L-carnitine on the physical performance of healthy adults cannot be explained by an increase in the carnitine muscle stores.
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Affiliation(s)
- Sandra Wächter
- Institute of Clinical Pharmacology, University of Berne, Switzerland
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26
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Tellioğlu AT, Uras KA, Yilmaz T, Alagözlü H, Tekdemir I, Karabağ O. The effect of carnitine on random-pattern flap survival in rats. Plast Reconstr Surg 2001; 108:959-62. [PMID: 11547153 DOI: 10.1097/00006534-200109150-00021] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Carnitine is an endogenous cofactor involved in the transport of long-chain fatty acids into the mitochondria where they undergo beta-oxidation. Through another reaction, carnitine produces free coenzyme A and reduces the ratio of acetyl-coenzyme A to coenzyme A, thereby enhancing oxidative use of glucose, augmenting adenosine triphosphate synthesis, and reducing lactate production and acidosis. Because of its regulatory action on the energy flow from the different oxidative sources, especially under ischemic conditions, carnitine has been used in cardiovascular diseases such as coronary heart disease, congestive heart failure, peripheral vascular disease, dyslipidemia, diabetes, and chronic renal diseases with satisfactory results. A flap is also a relatively ischemic tissue and may obtain benefit from carnitine. To investigate this, 30 rats were divided into three groups of 10 animals: a control group and two carnitine-treated groups. Random dorsal skin flaps were elevated on the rats. In the control group, no pharmacologic agents were used. Of the two treated groups, group 1 was treated with 50 mg/kg/day carnitine for 1 week and group 2 was treated with 100 mg/kg/day carnitine for 1 week. The areas of flap necrosis were measured in each group. The median areas of flap necrosis of the groups were 12.55, 9.23, and 4.9 cm2, respectively. There was a statistically significant improvement of flap necrosis in carnitine-treated groups compared with the control group (group 2, p = 0.001; group 3, p = 0.000). Furthermore, there was less necrosis in the high-dose carnitine-treated group than the low-dose carnitine-treated group. As a conclusion, carnitine may have a dose-dependent effect to increase flap survival in random skin flaps.
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Affiliation(s)
- A T Tellioğlu
- Department of Plastic and Reconstructive Surgery, Kirikkale University Faculty of Medicine, Turkey.
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27
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Brass EP, Adler S, Sietsema KE, Hiatt WR, Orlando AM, Amato A. Intravenous L-carnitine increases plasma carnitine, reduces fatigue, and may preserve exercise capacity in hemodialysis patients. Am J Kidney Dis 2001; 37:1018-28. [PMID: 11325685 DOI: 10.1016/s0272-6386(05)80019-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Exercise capacity in patients with end-stage renal disease (ESRD) remains impaired despite correction of anemia. Carnitine insufficiency may contribute to impaired exercise and functional capacities in patients with ESRD. Two randomized placebo-controlled trials were conducted to test whether intravenous L-carnitine improves exercise capacity (assessed by maximal rate of oxygen consumption [VO(2max)]) and quality of life (measured by the Kidney Disease Questionnaire [KDQ]) in patients with ESRD. In study A, patients were administered L-carnitine, 20 mg/kg (n = 28), or placebo (n = 28) intravenously at the conclusion of each thrice-weekly dialysis session for 24 weeks. In study B, a dose-ranging study, patients were administered intravenous L-carnitine, 10 mg/kg (n = 32), 20 mg/kg (n = 30), or 40 mg/kg (n = 32), or placebo (n = 33) as in study A. The prospective primary statistical analysis evaluated changes in VO(2max) in each study and specified that changes in the KDQ were assessed only in the combined populations. L-Carnitine supplementation increased plasma carnitine concentrations, but did not affect VO(2max) in either study. Because change in VO(2max) showed significant heterogeneity, a secondary analysis using a mixture of linear models approach on the combined study populations was performed. L-Carnitine therapy (combined all doses) was associated with a statistically significant smaller deterioration in VO(2max) (-0.88 +/- 0.26 versus -0.05 +/- 0.19 mL/kg/min, placebo versus L-carnitine, respectively; P = 0.009). L-Carnitine significantly improved the fatigue domain of the KDQ after 12 (P = 0.01) and 24 weeks (P = 0.03) of treatment compared with placebo using the primary analysis but did not significantly affect the total score (P = 0.10) or other domains of the instrument (P > 0.11). Carnitine was well tolerated, and no drug-related adverse effects were identified. Intravenous L-carnitine treatment increased plasma carnitine concentrations, improved patient-assessed fatigue, and may prevent the decline in peak exercise capacity in hemodialysis patients. VO(2max) in the primary analysis and other assessed end points were unaffected by carnitine therapy.
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Affiliation(s)
- E P Brass
- Department of Medicine, Harbor University of California at Los Angeles Medical Center, Torrance, CA 90509, USA.
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28
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Abstract
Hemodialysis (HD) patients often have low serum concentrations of free L-carnitine and decreased skeletal muscle stores. As L-carnitine is an essential cofactor in fatty acid and energy metabolism, it is possible that abnormal carnitine metabolism in dialysis patients may be associated with clinical problems such as skeletal myopathies, intradialytic symptoms, reduced cardiac function, and anemia. Studies have shown that L-carnitine supplementation in HD patients improves several complications seen in dialysis patients, including cardiac complications (arrhythmias, reduced output, low cardiothoracic ratio), limitation of exercise capacity, increased intradialytic hypotension, and muscle symptoms. The most promising results have been noted in the treatment of erythropoietin-resistant anemia. Routine administration of L-carnitine to all dialysis patients is not recommended at this time; however, a therapeutic trial of L-carnitine can be useful in symptomatic patients with certain clinical features unresponsive to the usual measures. These include intradialytic muscle cramps and hypotension, asthenia, cardiomyopathy, lowered ejection fraction, muscle weakness or myopathy, reduced oxygen consumption, and anemia requiring large doses of EPO.
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Affiliation(s)
- S Ahmad
- Scribner Kidney Center and the Department of Medicine, University of Washington, Seattle, Washington 98133, USA
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29
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Gatti R, De Palo CB, Spinella P, De Palo EF. Free carnitine and acetyl carnitine plasma levels and their relationship with body muscular mass in athletes. Amino Acids 1999; 14:361-9. [PMID: 9871480 DOI: 10.1007/bf01318855] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The purpose of the present study was to investigate the relationship between plasma carnitine concentration and body composition variation in relation to muscular and fat masses since there is no experimentally proved correlation between plasma carnitine and body masses. We used bioelectric impedance analysis (BIA), to determine body composition and to have a complete physical fitness evaluation. The post-absorptive plasma free carnitine and acetyl carnitine plasma levels, body composition as Fat-Free Mass (FFM) and Fat Mass (FM) in kg, as well as in percent of body mass, were analysed in 33 healthy subjects. A significant negative correlation was found between plasma acetyl carnitine and FFM in weight (kg) as well as in percent of body mass (respectively p < 0.0001; p < 0.01); a significant positive correlation was found only between FM in percent and plasma acetyl carnitine (p < 0.01). The observed negative correlation between plasma acetyl carnitine and muscular mass variation might reflect an oxidative metabolic muscle improvement in relation to muscular fat free mass increment and might be evidence that muscle metabolism change is in relation to plasma acetyl carnitine concentration.
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Affiliation(s)
- R Gatti
- Divisione di Patologia Medica III, Cattedra di Biochimica Clinica, Istituto di Semeiotica Medica, Università degli Studi di Padova, Italy
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30
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Abstract
Levocarnitine is a molecule required in mammalian energy metabolism. It removes the potentially toxic acyl groups from the cell helping to maintain normal metabolic functions. In addition, it facilitates the transport of long-chain fatty acids across the mitochondrial membrane for beta oxidation and subsequent energy production in skeletal muscle and myocardium. It has been shown in numerous studies that levocarnitine metabolism is abnormal in patients with end-stage renal disease. Significant dialytic loss of levocarnitine has been reported in addition to dietary changes undertaken in this population, which may decrease dietary levocarnitine intake. Recent studies have shown that levocarnitine administration to hemodialysis patients has improved exercise performance, intradialytic muscle cramps and hypotension episodes, and overall well-being. Ongoing and future studies will help to formulate more definite recommendations on the dose and the duration of levocarnitine therapy in dialysis patients.
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Affiliation(s)
- S Goral
- Assistant Professor of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
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31
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Brass EP, Hiatt WR. The role of carnitine and carnitine supplementation during exercise in man and in individuals with special needs. J Am Coll Nutr 1998; 17:207-15. [PMID: 9627906 DOI: 10.1080/07315724.1998.10718750] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Carnitine is critical for normal skeletal muscle bioenergetics. Carnitine has a dual role as it is required for long-chain fatty acid oxidation, and also shuttles accumulated acyl groups out of the mitochondria. Muscle requires optimization of both of these metabolic processes during peak exercise performance. Theoretically, carnitine availability may become limiting for either fatty acid oxidation or the removal of acyl-CoAs during exercise. Despite the theoretical basis for carnitine supplementation in otherwise healthy persons to improve exercise performance, clinical data have not demonstrated consistent benefits of carnitine administration. Additionally, most of the anticipated metabolic effects of carnitine supplementation have not been observed in healthy persons. The failure to demonstrate clinical efficacy of carnitine may reflect the complex pharmacokinetics and pharmacodynamics of carnitine supplementation, the challenges of clinical trial design for performance endpoints, or the adequacy of endogenous carnitine content to meet even extreme metabolic demands in the healthy state. In patients with end stage renal disease there is evidence of impaired cellular metabolism, the accumulation of metabolic intermediates and increased carnitine demands to support acylcarnitine production. Years of nutritional changes and dialysis therapy may also lower skeletal muscle carnitine content in these patients. Preliminary data have demonstrated beneficial effects of carnitine supplementation to improve muscle function and exercise capacity in these patients. Peripheral arterial disease (PAD) is also associated with altered muscle metabolic function and endogenous acylcarnitine accumulation. Therapy with either carnitine or propionylcarnitine has been shown to increase claudication-limited exercise capacity in patients with PAD. Further clinical research is needed to define the optimal use of carnitine and acylcarnitines as therapeutic modalities to improve exercise performance in disease states, and any potential benefit in healthy individuals.
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Affiliation(s)
- E P Brass
- Department of Medicine, Harbor-UCLA Medical Center, UCLA School of Medicine, Torrance 90509, USA
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32
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Clyne N. Physical working capacity in uremic patients. SCANDINAVIAN JOURNAL OF UROLOGY AND NEPHROLOGY 1996; 30:247-52. [PMID: 8908642 DOI: 10.3109/00365599609182300] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- N Clyne
- Department of Internal Medicine, Karolinska Hospital, Stockholm, Sweden
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33
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Akiba T, Matsui N, Shinohara S, Fujiwara H, Nomura T, Marumo F. Effects of recombinant human erythropoietin and exercise training on exercise capacity in hemodialysis patients. Artif Organs 1995; 19:1262-8. [PMID: 8967886 DOI: 10.1111/j.1525-1594.1995.tb02297.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effects of recombinant human erythropoietin (rHuEPO) and exercise training on exercise capacity were evaluated in 20 hemodialysis patients. After improvement of anemia by rHuEPO (Phase I), patients were divided into 2 groups. Group 1, 10 patients, was placed in a 3-month exercise training program. Group 2, 10 patients, served as a control group (Phase 2). A symptom-limited exercise tolerance test was performed at the start of Phase 1 and before and after Phase 2. Hemoglobin (Hb) values were kept constant throughout Phase 2. In Phase 1, maximum workloads (62.0 +/- 19.1 to 76.5 +/- 25.6 W, p < 0.001), maximum O2 uptake (VO2max) (18.7 +/- 3.5 to 2.2 +/- 5.9 ml/min/kg, p < 0.01), and VO2 at anaerobic threshold (AT) (VO2AT) (8.5 +/- 2.1 to 10.2 +/- 2.9 ml/min/kg, p < 0.01) were all improved by rHuEPO. However, in Phase 2, despite unchanged Hb values and maximum workloads, VO2max (20.7 +/- 4.6 to 17.6 +/- 2.6 ml/min/kg, p < 0.05) and VO2AT (10.6 +/- 1.4 to 9.5 +/- 1.8, ml/min/kg p < 0.05) were decreased in Group 2. However, in Group 1, maximum workloads (66.7 +/- 8.2 to 81.7 +/- 7.5 W, p < 0.01) were improved, and VO2max and VO2AT were not decreased significantly in the same period. Exercise training in rHuEPO-treated hemodialysis patients resulted in an improved aerobic exercise capacity, whereas those without exercise training did not have increased capacity. Throughout the study, O2 uptakes were lower than those of nonrenal anemic patients who had similar Hb values. Maximum lactate values also remained low. In conclusion, improvement in the exercise capacity in hemodialysis patients treated with rHuEPO was minimal. Some defects were suggested in the aerobic energy production system in skeletal muscle of dialysis patients. Anemia-improved patients should participate in incremental physical activity to maintain an improved exercise capacity.
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Affiliation(s)
- T Akiba
- Second Department of Internal Medicine, Tokyo Medical and Dental University, Japan
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34
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Giovenali P, Fenocchio D, Montanari G, Cancellotti C, D'Iddio S, Buoncristiani U, Pelagaggia M, Ribacchi R. Selective trophic effect of L-carnitine in type I and IIa skeletal muscle fibers. Kidney Int 1994; 46:1616-9. [PMID: 7700019 DOI: 10.1038/ki.1994.460] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Biopsies were taken from the vastus lateralis muscle of 26 chronic uremic patients before and after a 24-week treatment with L-carnitine given at the dose of 2 g i.v. at the end of hemodialysis, or in dialysis solution, or per os twice daily. The aim of the study was to evaluate both the muscle morphology in dialyzed subjects and the modification provoked by the therapy. All patients manifested a significant, even if variable, degree of muscular atrophy which involved all types of muscle fibers. After the treatment there was an increase of about 7% in the diameter of type I and type IIa fibers, which can utilize carnitine for fatty acid oxidation to produce energy, and a reduction in the atrophic fibers. No noteworthy changes were documented in type IIb fibers, which depend on glycolysis for energy production.
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Affiliation(s)
- P Giovenali
- II Cattedra Anatomia Istologia Patologica, Università di Perugia, Italy
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Hiatt WR, Koziol BJ, Shapiro JI, Brass EP. Carnitine metabolism during exercise in patients on chronic hemodialysis. Kidney Int 1992; 41:1613-9. [PMID: 1501417 DOI: 10.1038/ki.1992.233] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Patients on hemodialysis (HD) have impaired exercise performance. Carnitine homeostasis is also abnormal in this population. As carnitine is an important cofactor for muscle energy metabolism, exercise performance and skeletal muscle carnitine metabolism were characterized in eight HD patients, and in five age-matched controls. Each patient underwent graded bicycle exercise testing to define maximal performance, and prolonged exercise at 70% of their peak work capacity. Muscle (vastus lateralis) total carnitine content (carnitine plus all acylcarnitines) at rest was lower in HD patients than in controls (2320 +/- 1190 vs. 3800 +/- 940 nmol/g, P less than 0.05). In patients on HD, muscle carnitine content was inversely correlated to time on HD (r = -0.74, P less than 0.05), and positively correlated to peak exercise performance (r = 0.77, P less than 0.05). In patients on HD, 8 +/- 7% of the muscle carnitine pool at rest was short-chain acylcarnitines (similar to the distribution in controls), but 32 +/- 5% of the plasma carnitine pool consisted of short-chain acylcarnitines. With high-intensity exercise in patients on HD, muscle short-chain acylcarnitine content increased from 130 +/- 130 to 1380 +/- 820 nmol/g (P less than 0.01). The change in muscle short-chain acylcarnitine content with exercise was correlated with the increase in muscle lactate content (r = 0.88, P less than 0.01). In summary, patients on HD had a lower muscle total carnitine content than control subjects which was correlated to exercise performance.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- W R Hiatt
- Department of Medicine, University of Colorado School of Medicine, Denver
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