Acetyl-L-Carnitine (ALC) is a stabilized form of the amino acid metabolite L-Carnitine and is utilized in the same manner in the body. ALC plays an important role in protecting and supporting brain functions.
What is Carnitine and where does it come from?
L-Carnitine is a vitamin-like amino acid derivative. It plays an important role for maintaining energy production by transporting long-chain fatty acids into the mitochondrial matrix to be burned for energy. This function supports physical performance and weight management. Therefore, L-Carnitine and its esters, such as Acetyl-L-Carnitine and Propionyl-L-Carnitine, have received growing attentions for their uses in cardiovascular and neurological health.
L-Carnitine, along with its natural ester acylcarnitine, forms a critical part of the endogenous (natural to the body) carnitine pool in various tissues of mammals. The total L-Carnitine in human body is about 20 g, in which 98% is present in the skeletal and cardiac tissues, 1.4% in the liver and kidneys and 0.6% in extracellular fluids and other tissues. Of all these carnitine pools in the human body, about 25% are produced from the amino acids lysine and methionine and about 75% is derived directly from dietary sources such as meat, poultry, fish, and milk; with small amounts in wheat and avocados. So people with a limited diet of meat and dairy products tend to have lower L-Carnitine intakes.
L-Carnitine is a “conditionally essential” nutrient and a rare genetic disorder of L-carnitine metabolism causes carnitine deficiency, which is known to have major deleterious effects on the central nervous system. The limited intake of L-Carnitine can cause toxic accumulations of free fatty acids and the loss of energy. L-Carnitine is used worldwide as an effective treatment for carnitine deficiency and also has various nutritional and pharmaceutical applications.
L-Carnitine has a sister form, D-Carnitine, which may be formed as an impurity when producing the natural “L form”. The “D form” may have considerable side effects or even toxic influences on biochemical processes because it may inhibit an enzyme called carnitine acetyl transferase, leading to a depletion of the body’s L-Carnitine reserves. Separation and determination of any undesirable D-Carnitine is important to maintain the quality of our nutritional formulations and assure their proper function and safety. To maintain the quality of our products, NOW developed an HPLC testing method for simultaneous separation of L-Carnitine, Acetyl-L-Carnitine and various impurities, which include D-forms and crotonoylbetain. The content of D-Carnitine allowed in the European Pharmacopoeia and United States Pharmacopoeia is limited to about 4%. Our HPLC method has high sensitivity and selectivity and allows the detection of an impurity in the D-form at less than 0.5%. By using this new method to test the potency and verify the purity of our L-Carnitine products, NOW ensures the best quality of L-Carnitine products for our customers, while avoiding potentially harmful impurities.
Acetyl-L-Carnitine and Lipoic Acid significantly improves metabolic function while decreasing oxidative stress
Mitochondrial decay and increased oxidative stress play an important role in the aging process. This study theorized that supplementation with acetyl-L-carnitine and the antioxidant lipoic acid will reverse age-related metabolic decline. Acetyl-Lcarnitine is a mitochondrial metabolite of carnitine and reverses the age-related decline of carnitine levels in tissues. Lipoic acid is a cofactor for enzymes found in mitochondria. Young and old male rats were supplemented with acetyl-L-carnitine, lipoic acid, a combination of both substances, or given an unsupplemented control diet daily for one month. Compared with young rats, old rats fed the combination acetyl-L-carnitine and lipoic acid diet demonstrated significant increases in metabolic activity. In response to oxidative stress, the combination acetyl-Lcarnitine and lipoic acid diet reversed markers of lipid peroxidation in the older rats to levels comparable with levels in the young untreated animals. These observed effects were greater than with either acetyl-L-carnitine or lipoic acid alone. This short-term animal study suggests that a combination of acetyl-L-carnitine and lipoic acid appears to increase metabolic activity and lower oxidative stress in old animals. These preliminary findings should be confirmed because of the potential of these findings in managing the aging process.
Funding: National Institute on Aging and National Institute of Environmental Health Sciences, NIH; Ellison Medical Foundation; Department of Energy; Bruce and Giovanna Ames Foundation.
- B.A.B Bowman, Nutr. Rev., 50 (1992) 142
- T. Bohmer, Biochim. Biophys. Acta 343 (1974), p. 551
- R. Ferrari, C. Ceconi, S. Curello, E. Pain and O. Visioli, Mol. Cell. Biochem., 88 (1989) 161
- M. De Grandis, C. Mezzina, A. Fiaschi, P. Pinelli, G. Bazzato, M. Morachiello, J. Neurol. Sci., 46 (1980) 365
- D.B. Shennan, A. Grant, R.R. Ramsay, C. Burns, V.A. Zammit, Biochim. Biophys. Acta 1393 (1998) 49
- T M Hagen, J Liu, J Lykkesfeldt, CM Wehr, RT Ingersoll, V Vinarsky, JC Bartholomew, and BN Ames. Proceedings of the National Academy of Sciences (PNAS) 2002 99:1870-1875
Serving Size: 1 Vcap®
Servings Per Container: 100
Acetyl-L-Carnitine (from Acetyl-L-Carnitine HCL) 500 mg
Other Ingredients: Cellulose (capsule), Cellulose, Stearic Acid (vegetable source) and Magnesium Stearate (vegetable source).
Suggested Use: As a dietary supplement, take 1 Vcap® 1 to 3 times daily as needed.
Vcaps® is a registered trademark of Capsugel.