Possible Interaction: Acetylcarnitine and Carnitine

“BACKGROUND Human and animal studies indicate that pr pionyl-L-carnitine in creases car nitine co ntent and improves energy metabolism in the ischemic skeletal muscle.”

“Conclusion Carnitine supplementation improves acetylcarnitine formation and rescues metabolic flexibility in IGT-subjects.”

“Furthermore, carnitine supplementation increased post-exercise acetylcarnitine concentrations and reduced long-chain acylcarnitine species in IGT-subjects, suggesting the stimulation of a more complete fat oxidation in muscle.”

“In muscle, carnitine supplementation enhanced the increase in resting acetylcarnitine concentrations over the day (delta 7:00 AM versus 5:00 PM) in IGT-subjects.”

“… LC … LAC had significantly increased the percentage of forward sperm motility (MD 6.98; 95% CI 1.06–12.90; p = .02), total motile spermatozoa (MD …% CI 11.08–14.94; p < .00001) and the number of pregnancies (OR 3.76; 95% CI 1.66–8.50; p = .002).”

“Although the activity of carnitine acetyltransferase is sufficient to allow equilibrium between carnitine and coenzyme‐A pools, the exchange in TMA signal between carnitine and acetylcarnitine is slow in soleus following exercise on 7T 1H‐NMR time scale.”

“The investigators suggest that the reduced PDC activity is due to a carnitine-mediated increase in lipid-derived acetyl-… is consistent with theoretical models (Randle et al. 1963) the current data give limited experimental support in that the acetyl-carnitine/carnitine ratio , which reflects the …, was lower after carnitine ….”

“ Acetylcarnitine contributed the most to the increase of total esterified carnitine.”

“Daily urinary excretion of total carnitine was four to five times higher than controls after the first day of treatment, although the amounts of free carnitine and acetylcarnitine were decreased.”

“Addition of D-carnitine and L-acetylcarnitine resulted in diminished uptake of L-carnitine, suggesting that these substrates utilize the same transport mechanism.”

“Similar post-exercise free carnitine acetylcarnitine ratios in both groups suggest that the availability of carnitine in long-distance endurance horses might limit performance.”

“Conclusion: (1) Carnitine deficiency is a risk factor which is involved in CP-related cardiomyopathy; (2) serum and urinary carnitine levels should be monitored and viewed as indices of CP-induced multiple organ toxicity, and (3) carnitine supplementation, using PLC , prevents the development of CP-induced cardiotoxicity.”