L-Carnitine

C7H17CIN2O2 6490-20-6) see Carnitine i>L-carnitinamide hydroxide (C7H, N207, 91774-93-5) see Carnitine l>L-carnitine... 

Herbals Hypericum perforatum, L-carnitine/coenzyme QIO, Ginkgo biloba Study findings have been negative. 

Herzberg U, Sagen J (2001) Peripheral nerve exposure to HIV viral envelope protein gpl20 induces neuropathic pain and spinal gliosis. J Neuroimmunol 116(l) 29-39 Herzmann C, Johnson MA et al (2005) Long-term effect of acetyl-L-carnitine for antiretroviral toxic neuropathy. HIV Clin Trials 6(6) 344-350... 

Youle M, Oslo M (2007) A double-blind, parallel-group, placebo-controUed, multicentre study of acetyl L-carnitine in the symptomatic treatment of antiretroviral toxic neuropathy in patients with HIV-1 infection. HIV Med 8(4) 241-250... 

D-Camitine 14 L-Carnitine Thyroid inhibitor Multi-enzymatic pathway Agrobacterium sp. Single-stage fermentation of four processes [7]... 

Pettigrew JW, Levine J and McClure RJ (2000). Acetyl-L-carnitine physical-chemical, metabolic, and therapeutic properties Relevance for its mode of action in Alzheimer s disease and geriatric depression. Molecular Psychiatry, 5, 626-632. 

Tamai I, China K, Sai Y, Kobayashi D, Nezu J, Kawahara E et al. Na(+)-coupled transport of L-carnitine via high-affinity carnitine transporter OCTN2 and its sub-cellular localization in kidney. Biochim Biophys Acta 2001 1512(2) 273-284. 

Atroshi F, Rizzo A F, Westermarck T and Ali-Vehmas T (1998), Effects of tamoxifen, melatonin, coenzyme Q10 and L-carnitine supplementation on bacterial growth in the presence of mycotoxins , Pharmacol. Res., 38 (4), 289-295. 

Generalized carnitine deficiency, in its primary form and inherited as an autosomal recessive trait, is due to a defect of the specific high-affinity, low-concentration, carrier-mediated carnitine-uptake mechanism. The defect has been documented in cultured fibroblasts and muscle cultures, but the same uptake system is probably shared by heart and kidney, thus explaining the cardiomyopathy and the excessive leakage of carnitine into the urine. Oral L-carnitine supplementation results in dramatic improvement in cardiac function [4,8]. 

On the other hand, several probe substrates of carrier-mediated transport systems in the small intestine have been reported to be not absorbed by carrier-mediated mechanism in the rat colon in situ. Those include L-carnitine [23], methotrexate [18], cephradine [18], and 5-fluorouracil [18], as substrates of the L-carnitine carrier, folate carrier, peptide carrier, and pyrimidine carrier, respectively (Table 3.3). It is based on the nonsaturable nature of their transport. Particularly, the apparent membrane permeabilities of L-carnitine and methotrexate are negligibly low, suggesting that these compounds are practically unabsorbable from the colon. In the case of 5-fluorouracil, Na+-independence of transport was observed in situ [18] and also in everted sacs in vitro in the colon [21], while its carrier in the small intestine is known to be Na+-dependent. Furthermore, for ascorbate and nicotinate, as described in everted sacs in vitro [21], and L-dopa, as described in situ [24], carrier-mediated transport cannot be observed in the rat colon. 

Note Data represent the mean S.E. (n = 3). MW, molecular weight P0/w, octanol-to-water partition coefficient CLapp, apparent membrane permeability clearance SI, midgut area of the small intestine NA, not available or applicable. Absorption was evaluated in our laboratory using the closed loop of the rat intestine in situ (urethane anesthesia, 1.125 g/4.5 ml/kg, i.p.) in 60 min for riboflavin and L-camitine and 30 min for the others. For those that are transported by carriers in part (riboflavin and glycerol in both colon and SI, and L-carnitine, 5-fluorouracil, and cephradine in SI), absorption was evaluated at higher concentrations where the contribution of carrier-mediated transport is negligible. Values of P0/w were obtained from a report by Leo et al. [30] except for that of D-xylose, which was determined in our laboratory. a Data by single-pass perfusion experiments. b Unpublished data from our laboratory. 

Matsuda K, Yuasa H, Watanabe J (1998) Fractional absorption of L-carnitine after oral administration in rats Evaluation of absorption site and dose dependency. Biol Pharm Bull 21 752-755... 

A new chiral-achiral tandem-columns arrangement based on a commercially available TAG CSP connected in series with a Spherisorb S5 SCX column was developed for the enantio- and chemoselective dosage of propionyl L-carnitine and relative impurities in pharmaceutical batches [166]. Some chromatograms relative to the separation of carnitine and carnitine derivatives on a teicoplanin CSP are collected in Figure 2.18. 

Enzymatic hydroxylation of biological molecules is often catalyzed by hydroxylases. These types of enzymes are either oxygenases or peroxidases, in which the source of oxygen is O2 or H2O2, respectively. Cytochrome P-450-dependent enzymes represent a common class of enzymes that carry out hydroxylation reactions. L-Carnitine is a metabolite isolated from many organisms and its biosynthesis begins with the enzymatic hydroxylation of trimethyllysine. The intermediate, 3-hydroxyl-e-(A(A(ALtrimethyl)-L-lysine, is further... 

I. (1998) L-carnitine supplementation in childhood epilepsy current perspectives. Epilepsia 39 1216-1225. 

Food and feed Dietary supplement Carnipure tartrate L-Carnitine L-tartrate Lonza, Switz. 

Spagnoh A, Lucca U, Menasce G Long-term acetyl-L-carnitine treatment in Alzheimer s disease. Neurology 41 1726-1732, 1991... 

Propionyl-L-Carnitine HCI Tablet injection Chronic congestive heart failure... 

Acylcarnitine profiles are dependent on the clinical status of the patient at the time of sample collection [56, 57]. It is therefore important to provide the biochemical genetics laboratory with information regarding the clinical context during which the sample was collected. The laboratory must be conscientious of the fact that carnitine deficiency states can be associated with acylcarnitine profiles that lack any acylcarnitine species that are elevated above the reference range. Therefore, it is essential that the complete profiles are reviewed and even borderline elevated acylcarnitines should prompt further follow up in the presence of abnormally low free acetylcar-nitine (Fig. 3.2.2). If clinically indicated, a repeat sample should be collected at least 24 h after L-carnitine supplementation. 

Table 3.2.7 Mass assignment and reference range for acylcarnitine species accumulating in fibroblast cultures following incubation with palmitate, liCa-valine, liC>>-isoleucine, and L-carnitine...

Chalmers RA, Roe CR, Stacey , Hoppel CL (1988) Urinary excretion of L-carnitine and acylcarnitines by patients with disorders of organic acid metabolism evidence for secondary insufficiency of L-carnitine. Pediatr Res 18 1325-1328... 

Roe CR, Millington DS, Maltby DA, Kahler SG, Bohan TP (1984) L-carnitine therapy in isovaleric acidemia J Clin Invest 74 2290-2295... 

Yergey AL, Liberato DJ, Millington DS (1984) Thermospray liquid chromatography/mass spectrometry for the analysis of L-carnitine and its short-chain acyl derivatives. Anal Biochem 139 278-283... 

In one patient with acute valproate-associated encephalopathy associated with biochemical evidence of severe carnitine deficiency and a defect in valproate metabolism, L-carnitine substitution corrected the biochemical abnormalities, but the patient died (SED-13, 150) (1186). 

De Vivo DC, Bohan TP, Coulter DL, Dreifuss FE, Greenwood RS, Nordli DR Jr, Shields WD, Stafstrom CE, Tein I. L-carnitine supplementation in childhood epilepsy current perspectives. Epilepsia 1998 39(11) 1216—25. 

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