| Title: Effects of Alpha Lipoic Acid on Free Fatty Acid Oxidation Author(s): Walgren JL, Amani Z, McMillan JM, Locher M, Buse MG. Source: Metabolism. 2004 Feb;53(2):165-73. Content: Effect of R(+)alpha-lipoic acid on pyruvate metabolism and fatty acid oxidation in rat hepatocytes. Summary: The body's own natural form of ALA [(R)+Alpha Lipoic Acid] may prove to be useful in the control of type 2 diabetes. Department of Pharmacology, Medical University of South Carolina, Charleston, SC, USA. R-(+)-alpha-lipoic acid (R-LA) is the naturally occurring enantiomer of LA. It is a strong antioxidant and cofactor of key metabolic enzyme complexes catalyzing the decarboxylation of alpha-keto acids. Racemic LA (rac-LA) has shown promise in treating diabetic polyneuropathy, and some studies suggest that it improves glucose homeostasis in patients with type 2 diabetes. We examined the effects of R-LA on pyruvate metabolism and free fatty acid (FFA) oxidation in primary cultured hepatocytes isolated from 24-hour fasted rats. After overnight culture in serum-free medium, cells were pre-exposed to R-LA for 3 hours before assays. R-LA (25 to 200 micromol/L) significantly increased pyruvate oxidation ( approximately 2-fold at the highest dose tested) measured as (14)CO(2) production from [1-(14)C]pyruvate by the cells over 1 hour post-treatment. These effects correlated with proportional, significant increases in the activation state of the pyruvate dehydrogenase (PDH) complex. R-LA treatment inhibited glucose production from pyruvate by approximately 50% at 50 micromol/L R-LA and approximately 90% at 200 micromol/L. Palmitate oxidation was measured in hepatocytes cultured in the presence of albumin and physiological (0.1 mmol/L) or high (1.5 mmol/L) concentrations of FFA. The latter markedly enhanced FFA oxidation. R-LA treatment significantly inhibited FFA oxidation in both media, but was more effective in high FFA, where it reduced FFA oxidation by 48% to 82% at 25 to 200 micromol/L, respectively. Identical doses of R-LA did not affect FFA oxidation by L6 myotubes (a cell culture model for skeletal muscle) in either high or low FFA medium, but enhanced pyruvate oxidation. In conclusion, 3-hour exposure of primary cultured rat hepatocytes to R-LA at therapeutically relevant concentrations increased pyruvate oxidation, apparently by activation of the PDH complex, and decreased gluconeogenesis and FFA oxidation. These features may prove useful in the control of type 2 diabetes. More/Expanded Article Information: [ click here ] Click Here To View An Alpha Lipoic Acid Supplier Website! |
|
This site is a service of CCWEBGROUP that provides and reports interesting information that is available to the general public. CCWEBGROUP is not in any way involved in performing the scientific studies, completing the analyses, nor evaluating the results.
Many studies reported herein have been performed on laboratory animals and not on humans. While some results of animal trials are later found to be similar in human trials, we have no way of knowing whether or not this will be the case. This information is not presented as medical advice and no conclusions regarding the effectiveness or lack of such should be drawn from this information. As with any information that pertains to your health, please discuss your questions and/or conclusions with your physician or healthcare provider. |
|
copyright © 2005 :: ccwebgroup :: all rights reserved
|