Effect Of L-carnitine Supplementation Research Articles

Effect of L-carnitine supplementation on the body carnitine pool, skeletal muscle energy metabolism and physical performance in male vegetarians.

More than 95% of the body carnitine is located in skeletal muscle, where it is essential for energy metabolism. Vegetarians ingest less carnitine and carnitine precursors and have lower plasma carnitine concentrations than omnivores. Principle aims of the current study were to assess the plasma and skeletal muscle carnitine content and physical performance of male vegetarians and matched omnivores under basal conditions and after L-carnitine supplementation. Sixteen vegetarians and eight omnivores participated in this interventional study with oral supplementation of 2 g L-carnitine for 12 weeks. Before carnitine supplementation, vegetarians had a 10% lower plasma carnitine concentration, but maintained skeletal muscle carnitine stores compared to omnivores. Skeletal muscle phosphocreatine, ATP, glycogen and lactate contents were also not different from omnivores. Maximal oxygen uptake (VO2max) and workload (P max) per bodyweight (bicycle spiroergometry) were not significantly different between vegetarians and omnivores. Sub-maximal exercise (75% VO2max for 1 h) revealed no significant differences between vegetarians and omnivores (respiratory exchange ratio, blood lactate and muscle metabolites). Supplementation with L-carnitine significantly increased the total plasma carnitine concentration (24% in omnivores, 31% in vegetarians) and the muscle carnitine content in vegetarians (13%). Despite this increase, P max and VO2max as well as muscle phosphocreatine, lactate and glycogen were not significantly affected by carnitine administration. Vegetarians have lower plasma carnitine concentrations, but maintained muscle carnitine stores compared to omnivores. Oral L-carnitine supplementation normalizes the plasma carnitine stores and slightly increases the skeletal muscle carnitine content in vegetarians, but without affecting muscle function and energy metabolism.

Effect of Dietary L-Carnitine Supplementation with Animal Fat on Carcass Characteristics of Broiler Chicken

Study was carried out to find out the effect of L-carnitine supplementation on carcass characteristics in Venncobb broiler chicks fed with diet containing animal fat. Eighty day old commercial broiler chicks were randomly allotted to two treatment groups (T1 and T2) with four replicates of ten chicks each. The birds were fed with standard broiler chicken ration (BIS, 1992) containing 5% animal fat. T1 was the control, while T2 was supplemented with L-carnitine (900 mg/kg feed). At the end of 42 days, five birds from each treatment were slaughtered in order to determine carcass traits and organ weights. The results revealed that the supplementation of L-carnitine lowered the abdominal fat content of birds. However, L-carnitine supplementation had no effect on the body weight gain, slaughter weight, carcass weight, dressing percentage, giblet yield percentage and weight of internal organs.

Effects of L-Carnitine Supplementation on Growth Performance and Fatty Acid Proportion in Epididymal Adipose Tissue of Rats Fed Diets containing Fat from Different Sources

Effects of L-Carnitine Supplementation on Growth Performance and Fatty Acid Proportion in Epididymal Adipose Tissue of Rats Fed Diets containing Fat from Different Sources Two experiments were conducted to evaluate the effects of Lcarnitine supplementation on growth performance and epididymal adipose tissue fatty acid composition in rats fed diets containing different sources of fat. In the first study, rats were assigned to four groups receiving dietary treatments to evaluate the effects of supplementation with L-carnitine 0 ppm or L-carnitine 50 ppm in combination with two types of dietary fat: 100% soybean oil and a mixture of 50% soybean oil and 50% beef tallow. In the second study, the animals walked 2 h/day at a speed of 840 m/h. No significant differences were observed in the growth test results of each study. In experiment 1, the total saturated fatty acid (SFA) proportion was significantly higher in the L-carnitine 0 ppm 50% soybean oil and 50% beef tallow group than in the other groups. Dietary Lcarnitine suppressed the increase in the SFA proportion observed upon beef tallow consumption. In experiment 2, Lcarnitine decreased the SFA proportion and increased the monounsaturated fatty acid (MUFA) proportion. No interaction between the ingested fat type and L-carnitine supplementation on the proportions of individual fatty acids was observed, but Lcarnitine supplementation increased the C16:1 proportion and decreased the C18:0 proportion as a main effect in experiment 2. In conclusion, the current results suggest that dietary Lcarnitine decreased the SFA proportion in accordance with C18:0 utilization for energy production in walking rats.

Effects of L-carnitine supplementation on oxidative stress and antioxidant enzymes activities in patients with coronary artery disease: a randomized, placebo-controlled trial.

BackgroundCardiovascular disease is the leading cause of death worldwide. Higher oxidative stress may contribute to the pathogenesis of coronary artery disease (CAD). The purpose of this study was to investigate the effect of L-carnitine (LC, 1000 mg/d) on the markers of oxidative stress and antioxidant enzymes activities in CAD patients.MethodsWe enrolled 47 CAD patients in the study. The CAD patients were identified by cardiac catheterization as having at least 50% stenosis of one major coronary artery. The subjects were randomly assigned to the placebo (n = 24) and LC (n = 23) groups. The intervention was administered for 12 weeks. The levels of serum LC, plasma malondialdehyde (MDA), and erythrocyte antioxidant enzymes activities [catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx)] were measured before and after intervention.ResultsThirty-nine subjects completed the study (placebo, n = 19; LC, n = 20). After 12 weeks of LC supplementation, the level of MDA was significantly reduced (2.0 ± 0.3 to 1.8 ± 0.3 μmol/L, P = 0.02) and the level of LC (33.6 ± 13.6 to 40.0 ± 12.0 μmol/L, P = 0.04) and antioxidant enzymes activities [CAT (12.7 ± 5.5 to 13.1 ± 5.8 U/mg of protein, P = 0.02), SOD (14.8 ± 2.9 to 20.7 ± 5.8 U/mg of protein, P < 0.01), and GPx (20.3 ± 3.4 to 23.0 ± 3.1 U/mg of protein, P = 0.01)] were significantly increased. The level of LC was significantly positively correlated with the antioxidant enzymes activities (CAT, β = 0.87, P = 0.02; SOD, β = 0.72, P < 0.01).ConclusionLC supplementation at a dose of 1000 mg/d was associated with a significant reduction in oxidative stress and an increase in antioxidant enzymes activities in CAD patients. CAD patients might benefit from using LC supplements to increase their anti-oxidation capacity.Trial registrationClinical Trials.gov Identifier: NCT01819701.

Effect of L-carnitine Supplementation on Nutritional Status and Physical Performance Under Calorie Restriction.

L-carnitine is popular as a potential ergogenic aid because of its role in the conversion of fat into energy. The present study was undertaken to investigate the effect of short term supplementation of L-carnitine on metabolic markers and physical efficiency tests under short term calorie restriction. Male albino rats were divided into four groups (n=12 in each)-control, calorie restricted (CR for 5days, 25% of basal food intake), L-carnitine supplemented (CAR, given orally for 5days at a dose of 100mg/kg), CR with L-carnitine supplementation (CR+CAR). Food intake and body weight of the rats were measured along with biochemical variables like blood glucose, tissue glycogen, plasma and muscle protein and enzymatic activities of CPT-1 (carnitine palmitoyl transferase-1) and AMP kinase. Results demonstrated that L-carnitine caused marked increase in muscle glycogen, plasma protein, CPT-1 activity and swim time of rats (P<0.05) on short term supplementation. In addition to the substantive effects caused by CR alone, L-carnitine under CR significantly affected muscle glycogen, plasma protein, CPT-1 activity and AMP kinase (P<0.05). Short term CR along with L-carnitine also resulted in increased swim time of rats than control, CR and L-carnitine treated rats (P<0.05). The present study was an attempt towards developing an approach for better adherence to dietary restriction regimen, with the use of L-carnitine.

Effect of L-carnitine supplementation on drake semen quality

This study was conducted to determine the effect on semen quality traits of supplementing the diets of Iraqi drakes with L-carnitine. Forty eight male Iraqi ducks, 30 weeks old, were randomly allocated to four treatments with 12 drakes per treatment group, replicated three times, with four drakes per replicate. The treatment groups consisted of birds fed a diet free of L-carnitine (T1, control group); birds fed a diet containing 50 mg L-carnitine/kg diet (T2); birds fed a diet containing 100 mg L-carnitine/kg diet (T3); and birds fed a diet containing 150 mg L-carnitine/kg diet. The drakes were fed the experimental diets only during the experimental period, which lasted three months. The semen quality traits that were investigated were ejaculate volume, mass and individual motility of spermatozoa, spermatocrit, spermatozoa concentration, percentages of dead and abnormal spermatozoa and acrosomal abnormalities. Supplementing the diet of drakes with L-carnitine at the levels of 50 - 150 mg/kg diet significantly increased ejaculate volume, spermatocrit, mass and individual motility of spermatozoa, and concentration of spermatozoa, while percentages of dead and abnormal spermatozoa and acrosomal abnormalities were decreased. However, T4 (150 mg L-carnitine/kg diet) recorded the best results in relation to all semen quality traits included in this study. Dietary supplementation with L-carnitine improved the semen quality of local drakes; therefore L-carnitine can be used as an efficient feed additive to improve the reproductive performance of male ducks.

L-カルニチン補充療法によりESA低反応性貧血の改善を認めた維持血液透析症例

L-カルニチン補充療法によりESA低反応性貧血の改善を認めた維持血液透析症例

Positive influence ofl-carnitine on the different muscle fibres types of racing pigeons

Succinate dehydrogenase (SDH), Ca(2+) ATPase, Lactate dehydrogenase (LDH), are involved in energy metabolism. These enzymes can be used as indicators of the energy capacity of aerobic cells. The study investigated the effects of L-carnitine supplementation on M. pectoralis superficialis, M. pectoralis profundus, M. extensor carpi radialis muscle and M. flexor carpi ulnaris. Twenty-eight racing pigeons hatched at the same time were divided randomly into three groups. Eight pigeons, which were used as the control group, were sacrificed at 92-day old. The remaining twenty pigeons continued training until they reached 157-day old, with half the pigeons getting 25 mg/head/day of L-carnitine, while the other half given the same amount of water. The pigeons were assessed by histochemical methods and reverse transcription polymerase chain reaction (RT-PCR). To assess influence of L-carnitine on muscle fibre composition and the performance of three genes' mRNA, this study applied SDH localization, SDH, Ca(2+) ATPase and LDH mRNA expression to examine the results after oral administration of L-carnitine in vivo in racing pigeons. The results showed that L-carnitine significantly elevated the amount of white muscle fibre type IIa (p < 0.05). The mRNA expression quantities of SDH and LDH gene was higher via RT-PCR method. However, the expression of Ca(2+) ATPase remains similar. In conclusion, appropriate oral administration of L-carnitine of 25 mg/pigeon/day will result in an improvement of muscles related to flying.

Effect of hemodialysis session on the dynamics of carnitine ester profile changes in l-carnitine pretreated end-stage renal disease patients

Carnitine deficiency is common in end-stage renal disease (ESRD) patients receiving hemodialysis (HD) treatment. We investigated the effects of L-carnitine supplementation on acyl carnitine (AC) profile and the changes of distinct ACs during a single HD session in long-term L-carnitine pretreated ESRD patients. Twenty non-diabetic adult patients and 37 healthy controls were studied. Blood samples were drawn before and after 12 weeks of carnitine supplementation, then hourly during an HD session, as well as 30 min after the end of the session. Free and individual AC plasma levels were determined by using ESI MS/MS technique. HD patients showed lower free- and total carnitine levels and elevated ACs and acyl/free carnitine ratio before carnitine supplementation. The L-carnitine supplementation resulted in dramatic elevation of all carnitine esters. The HD session induced a progressive decline in free, short-chain, and dicarboxylic ACs (~80 % of pre-HD amount was washed out); the decrease of medium-chain ACs proved to be more moderate (~60 % washed out), whereas the long-chain ACs remained unaffected. Already 30 min after HD, a substantial increase was seen in free carnitine concentration (reaching 26 % of predialysis level) and the ACs also started to replenish (to 21-52 % of predialysis levels), without further exogenous carnitine load. The washout induced by HD session results in variable depletion of short-, medium-, and long-chain carnitine esters in carnitine-pretreated patients; the recovery of the circulating carnitine esters from the body stores occurs within 30 min after the cessation of the HD procedure.

The Effects of Carnitine Supplementation in Hemodialysis Patients

Objectives: Patients receiving hemodialysis have been shown to be carnitine deficient due to many causes. Tissues, especially the skeletal muscle and myocardium, require carnitine for the production of energy. This study was performed to find out the effects of L-carnitine supplementation on muscular symptoms and cardiac functions in dialysis patients. Methods: Among 72 hemodialysis patients, 40 patients who showed decreased free carnitine levels were selected to receive L-carnitine intravenously after each hemodialysis session for 6 months. Before and after supplementation, echocardiography, various neurologic examinations and questionnaires were obtained. Results: After carnitine treatment for 6 months (1∼1.5 g per every hemodialysis session), the blood level of carnitine was increased more than 10 times (19.04±7.12 μmol/L vs. 267.24±69.94 μmol/L, P＜0.001). The left ventricular ejection fraction was improved in the patients who have less than 60% of ejection fraction (56.45±2.53% vs. 60.44±6.29%, P=0.03) after carnitine treatment. The neurological symptom score and isometric muscle power (pinch power) were improved, but the total neuropathy score, activities of daily living scale and grip power were not changed after carnitine supplementation on dialysis patients. Conclusion: Regular L-carnitine supplementation on hemodialysis patients can improve their left ventricular ejection fraction and some parts of functionality. (Ewha Med J 2012;35(2):89-94)

産歴の多い繁殖雌豚の分娩前後にL-カルニチンを短期給与することが母豚の体重変化および子豚の成長に及ぼす影響

産歴の多い繁殖雌豚の分娩前後にL-カルニチンを短期給与することが母豚の体重変化および子豚の成長に及ぼす影響

体外発生培地へのL-カルニチン添加がウシ体外受精由来胚盤胞の脂質含量および凍結・融解後の生存性に及ぼす影響

体外発生培地へのL-カルニチン添加がウシ体外受精由来胚盤胞の脂質含量および凍結・融解後の生存性に及ぼす影響

Effects of L-carnitine supplementation on quality characteristics of fresh pork bellies from pigs fed 3 levels of corn oil1

Crossbred pigs (n = 216) were used to test the effect of supplemental L-carnitine (CARN) on the fatty acid composition and quality characteristics of fresh pork bellies from pigs fed diets formulated with different inclusion levels of corn oil. Pigs were blocked by BW (43.6 ± 1.0 kg) and allotted randomly to pens of 6 pigs within blocks. Then, within blocks, pens were assigned randomly to 1 of 6 dietary treatments in a 2 × 3 factorial arrangement, with either 0 or 100 mg/kg of supplemental CARN and 3 dietary inclusion levels (0, 2, or 4%) of corn oil (CO). When the lightest block weighed 125.0 kg, all pigs were slaughtered, and left-side bellies were captured during carcass fabrication for quality data collection. Fresh pork bellies were evaluated for length, width, thickness, and firmness (bar-suspension and Instron-compression methods) before a 2.5-cm-wide strip of belly was removed and subsequently dissected into subcutaneous fat, primary lean (latissimus dorsi), secondary lean (cutaneous trunci), and intermuscular fat for fatty acid composition determination. Although belly length, width, and thickness of fresh pork bellies were not affected by CARN (P ≥ 0.128) or CO (P ≥ 0.073), belly firmness decreased linearly (P < 0.001) with increasing dietary CO, but there was no (P ≥ 0.137) effect of CARN on any belly firmness measure. Dietary CARN increased (P < 0.05) the proportion of total SFA in the intermuscular fat layer, increased (P < 0.05) the proportion of total MUFA in the primary and secondary lean layers, and decreased (P < 0.05) the proportion of total PUFA in the intermuscular fat and secondary lean layers of pork bellies. Moreover, the SFA and MUFA compositions decreased linearly (P < 0.001) with increasing dietary CO, and the rate of the decrease in SFA composition was greater (P < 0.001) in the fat layers than the lean layers. Conversely, the PUFA content increased linearly (P < 0.001) with increasing dietary CO, and the rate of the increase in PUFA was greater (P < 0.001) in the fat than the lean layers, and greater (P = 0.022) in the primary than secondary lean layer. Results from this study would indicate that differences in the amount and rate of fatty acid deposition associated with feeding increased amounts of CO, along with moisture differences among the belly layers, combine to negatively affect fresh pork belly firmness.

L-Carnitine induces recovery of liver lipid metabolism in cancer cachexia

Cancer cachexia causes metabolic alterations with a marked effect on hepatic lipid metabolism. L-Carnitine modulates lipid metabolism and its supplementation has been proposed as a therapeutic strategy in many diseases. In the present study, the effects of L-carnitine supplementation on gene expression and on liver lipid metabolism-related proteins was investigated in cachectic tumour-bearing rats. Wistar rats were assigned to receive 1 g/kg of L-carnitine or saline. After 14 days, supplemented and control animals were assigned to a control (N), control supplemented with L-carnitine (CN), tumour-bearing Walker 256 carcinosarcoma (TB) and tumour-bearing supplemented with L-carnitine (CTB) group. The mRNA expression of carnitine palmitoyltransferase I and II (CPT I and II), microsomal triglyceride transfer protein (MTP), liver fatty acid-binding protein (L-FABP), fatty acid translocase (FAT/CD36), peroxisome proliferator-activated receptor-alpha (PPAR-alpha) and organic cation transporter 2 (OCTN2) was assessed, and the maximal activity of CPT I and II in the liver measured, along with plasma and liver triacylglycerol content. The gene expression of MTP, and CPT I catalytic activity were reduced in TB, who also showed increased liver (150%) and plasma (3.3-fold) triacylglycerol content. L-Carnitine supplementation was able to restore these parameters back to control values (p<0.05). These data show that L-carnitine preserves hepatic lipid metabolism in tumour-bearing animals, suggesting its supplementation to be of potential interest in cachexia.

Effects of Feed Supplementation with L-carnitine on Growth and Body Composition of Asian Catfish, Clarias batrachus Fry

Desai, A.S., Singh, R.K., Sapkale, P.H. and Patil, S.D. 2010. Effects of feed supplementation with L-carnitine on growth and body composition of Asian catfish, Clarias batrachus fry. J. Appl. Anim. Res., 38: 153–157. To evaluate the effect of L-carnitine supplementation (0, 0.25, 0.5, 0.75, 1.0 g L-carnitine/kg diet) on growth and body composition 60 fries (20X3 replicates of Clarias batrachus in each group were fed for 90 d. Weight gain (7.43 ± 0.5 g), specific growth rate (3.98 ± 0.29 %/day), feed conversion efficiency (48.53±1.77%) and protein efficiency ratio (1.62 ± 0.07) were significantly higher for diet with 0.50 g L-carnitine/kg. There was no difference (P>0.05) in protein, moisture and ash contents while lipid content decreased with increasing L-carnitine level. Hepatosomatic indices also decreased with increasing L-carnitine level. The feeding results concluded that the 0.50 g L-carnitine I kg diet was optimum for good growth of C. batrachus fry.

Effects of L-Carnitine supplement on plasma coagulation and anticoagulation factors in hemodialysis patients

Background: Hypercoagulability is an important risk factor for thrombosis and its complications in hemodialysis patients. This study was designed to investigate the effects of l-carnitine supplement on plasma coagulation and anticoagulation factors in hemodialysis patients. Methods: Thirty-six hemodialysis patients were randomly assigned to either a carnitine or a placebo group. Patients in the carnitine group received 1000 mg/day oral l-carnitine for 12 weeks, whereas patients in the placebo group received a corresponding placebo. At baseline and the end of week 12, 5 mL blood was collected after a 12- to 14-hour fast and plasma fibrinogen concentration, activity of plasma protein C, coagulation factors V, VII, IX, and serum concentrations of tissue plasminogen activator (tPA), plasminogen activator inhibitor type-1 (PAI-1), free carnitine, and C-reactive protein (CRP) were measured. Results: In the carnitine group, mean serum free carnitine concentration increased significantly to 150% of baseline (p < 0.001), whereas plasma fibrinogen and serum CRP had 98 mg/dL (p < 0.01) and 41% (p < 0.01) significant decreases, respectively, at the end of week 12 compared with baseline. The reductions were significant compared with the placebo group (p < 0.05). No significant differences were observed between the two groups with regard to mean changes of the activity of plasma protein C, coagulation factors V, VII, IX, and serum PAI-1 to tPA ratio. Conclusion: l-Carnitine supplement reduces serum CRP, a marker of systemic inflammation, and plasma fibrinogen, an inflammation-related coagulation factor, in hemodialysis patients. Therefore, l-carnitine may play an effective role in preventing cardiovascular diseases in these patients.

Effect of L‐carnitine on proliferative response and mRNA expression of some of its associated factors in splenic mononuclear cells of male broiler chicks

The effect of L-carnitine supplementation on mitogen (concanavalin A, Con A) induced proliferation of mononuclear cells (MNC) in the spleen was investigated in broiler chickens at different ages. Day-old chickens were fed a diet supplemented with or without L-carnitine (100 ppm) for 24 days. The carnitine-supplemented group showed greater proliferation of MNC in the spleen in response to Con A than that of the control group at 24 days of age. In addition, at 24 days of age the carnitine-supplemented group showed higher expression of interleukin (IL)-2 and interferon (IFN)-gamma mRNA, but lower expression of inducible nitric oxide synthase (iNOS) in the Con A-stimulated splenic MNC than the control group. The enhancement effect of L-carnitine on MNC proliferation and IL-2 mRNA expression was not found in chicks at 14 days of age. Addition of L-carnitine (50 nmol/mL) to the culture medium enhanced proliferation and IL-2 mRNA expression of splenic MNC obtained from 24-day-old but not from 14-day-old broiler chickens. The results suggest that L-carnitine is capable of enhancing MNC proliferation in broiler chickens at 24 days of age partly through increasing IL-2 and IFN-gamma production and decreasing NO production.

The effect of l-carnitine supplementation on the arterial stiffness in patients on hemodialysis

The effect of l-carnitine supplementation on the arterial stiffness in patients on hemodialysis

Influence of l-carnitine on metabolism and performance of sows

In recent years, l-carnitine has been used increasingly as a supplement in livestock animals. The present review gives an overview of the effects of dietary l-carnitine supplementation on the reproductive performance of sows. Results concerning the effect of l-carnitine supplementation during pregnancy on litter sizes are controversial. There are some studies reporting an increased number of piglets born alive per litter, while others could not find such an effect. In contrast, most studies performed show consistently that l-carnitine supplementation to a sow diet low in native carnitine during gestation increases piglet and litter weights at birth and enhances growth of litters during the suckling period. Biochemical mechanisms underlying the favourable effect of carnitine on intra-uterine growth have not been fully elucidated. There is, however, some evidence that carnitine influences the insulin-like growth factor-axis in sows and leads to greater placentae, which in turn improves intra-uterine nutrition, and stimulates oxidation of glucose in the fetuses. These effects may, at least in part, be responsible for higher birth weights of piglets. The stimulating effect of carnitine on growth of the litters might be due to an improved suckling behaviour of piglets born to l-carnitine-supplemented sows, causing the sows' milk production to rise. In conclusion, recent studies have clearly shown that dietary l-carnitine supplementation increases the reproductive performance of sows. These findings suggest that endogenous de novo synthesis of carnitine is insufficient to meet the metabolic requirement of sows during gestation.

Effect of L-carnitine supplementation on the sGC/cGMP pathway in vascular relaxing responses from exercised rats

Background It has been largely documented the beneficial effects of physical training on the endothelium-derived relaxing response by increasing nitric oxide production and/or its bioavailability to the smooth muscle [1]. L-carnitine (LCar) has been used as important supplement to regulate body composition associated with lipid metabolism. However, no studies exist investigating the effect of L-Car intake associated with dynamic exercise on the NO-independent sGC/cGMP pathway in the vascular responsiveness in rats. Thus, the aim of this work was to investigate the effect of L-Car supplementation on the NO-independent sGC/cGMP pathway in aortic and mesenteric rings in trained rats.