Carnitine


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Related to Carnitine: Carnitine deficiency, acetyl l-carnitine

carnitine

[′kär·nə‚tēn]
(biochemistry)
C7H15NO3α-Amino-β-hydroxybutyric acid trimethylbetaine; a constituent of striated muscle and liver, identical with vitamin B T.

Carnitine

 

betaine-γ-amino-β-oxybutyric acid, (CH3)3NCH2CH(OH)CH2CO2, a crystalline compound with basic properties; dissolves readily in water and alcohol. Its molecular mass is 161.21, and its melting point, 195°-197°C (with decomposition).

Carnitine is primarily found in animal muscle, from which it was first extracted by V. S. Gulevich (1905); it is also found in bacteria and plants. It takes part in fatty exchange within an organism by acting as a carrier of fatty acid radicals through the membranes of the mitochondria. These membranes are impermeable to activated fatty acids (compounds with coenzyme A). With the aid of carnitine, therefore, fatty acids enter the scope of activity of the oxidizing enzymes localized within the mitochondria. Carnitine apparently also participates in the reverse transport of fatty acids. It is an essential dietary constituent and a growth factor in certain insects; therefore it is considered to be a vitamin (vitamin BT).

References in periodicals archive ?
Vice Chair of Translational Research for the Lerner Research Institute and section head of Preventive Cardiology and Rehabilitation in the Miller Family Heart and Vascular Institute at Cleveland Clinic, and Robert Koeth, a medical student at the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University tested the carnitine and TMAO levels of omnivores, vegans and vegetarians, and examined the clinical data of 2,595 patients undergoing elective cardiac evaluations.
New research suggests that carnitine and choline may play a role.
These carnitine findings were based on a sub-study of 10 people.
Getting back to the Cleveland Clinic study which claims that carnitine causes atherosclerosis: As I said before, the media went hog wild, spreading faulty information and scaring lots of folks, including not only patients who are carnitine takers, but parents of youngsters who have been on carnitine for years.
The study tested the carnitine and TMAO levels of omnivores, vegans and vegetarians, and examined the clinical data of 2,595 patients undergoing elective cardiac evaluations.
Carnitine, acetylcarnitine and the activity of carnitine acyltransferases in seminal plasma and spermatozoa of men, rams and rats.
Stedman Nutrition and Metabolism Center, also performed tests on human muscle cells that showed supplementing with carnitine might help older people with prediabetes, diabetes, and other disorders that make glucose (sugar) metabolism difficult.
Certainly, carnitine is not the panacea or miracle cure' we seek for every illness that causes parents and doctors sleepless nights.
Normally propionyl-CoA is metabolized to methylmalonyl-CoA by the action of propionyl-CoA carboxylase (PCC), but if the metabolite is in excess the propionyl species is released from the mitochondrion after conversion by carnitine palmitoyl transferase II to the corresponding acylcarnitine (Fig.
Dietary carnitine significantly decreased the mRNA level of tartrate-resistant acid phosphatase (TRAP), an indicator of bone resorption by 72.
Although the results of the present study (Figures (1), (2) and (3)) are consistent with the results of researches conducted on the effect of vitamins E and C as antioxidant on the quality of frozen-thawed sperm using rapid cryopreservation method in the comparison of oligospermia patients and normal people, the lack of significant effect on improving normal morphology of the sperm [21] or the use of oral carnitine for 6 months, and the lack of effect on the increase of normal sperm forms [17], a reverse result was expected due to the antioxidant effect of l-carnitine.