4 replies to this topic

[Matthew Butler]

So, I found out that ALCAR( Acetyl-L-Carnitine) is barley absorbed through oral supplementation. If I ordered my own ALCAR powder, would supplementing horsetail extract help with this problem. Maybe I could find a way to enterically coat my capsules ( not sure if that would help)? I was told that it may be possible to take regular L-Carnitine that it may help in the absorption of ALCAR, I cannot verify this. Any input would be appreciated.

[blood]

Where did you read that ALCAR is poorly absorbed?

[Matthew Butler]

I would post link, but I am not allowed to, due to new forum membership? however, if you google "ALCAR bio availability" you should at least see one website. I saw read about it in an e- journal through my University, but through google I am seeing this site called examine, that keeps showing on the first page of results. pretty much, it says that the orally taken supplement is not very well received. So far, the only way around this, that is suggested is taking very high doses of ALCAR, which is what I assume is the reccomended dosage you will see on every bottle/can/ect.

IS there a way other than this?

[Kevnzworld]

Kinetics, Pharmacokinetics, and Regulation of l-Carnitine and Acetyl-l-carnitine Metabolism

In vivo, circulating acetyl-l-carnitine concentration was increased 43% after oral acetyl-l-carnitine supplements of 2 g/day, indicating that acetyl-l-carnitine is absorbed at least partially without hydrolysis. After single-dose intravenous administration (0.5 g), acetyl-l-carnitine is rapidly, but not completely hydrolyzed, and acetyl-l-carnitine and l-carnitine concentrations return to baseline within 12 h. At normal circulating l-carnitine concentrations, renal l-carnitine reabsorption is highly efficient (90-99% of filtered load; clearance, 1-3 mL/min), but displays saturation kinetics. Thus, as circulating l-carnitine concentration increases (as after high-dose intravenous or oral administration of l-carnitine), efficiency of reabsorption decreases and clearance increases, resulting in rapid decline of circulating l-carnitine concentration to baseline. Elimination kinetics for acetyl-l-carnitine are similar to those for l-carnitine. There is evidence for renal tubular secretion of both l-carnitine and acetyl-l-carnitine. Future research should address the correlation of supplement dosage, changes and maintenance of tissue l-carnitine and acetyl-l-carnitine concentrations, and metabolic and functional changes and outcomes.

http://onlinelibrary...enticated=false

[Matthew Butler]

L-Carnitine and ALCAR are absorbed in the intestines (jujenum) mostly by the organic cation transporter 2 (OCTN2)[49][50]which is a sodium dependent transporter.[38] This transporters takes up L-carnitine molecules, and while ALCAR needs to be deacetylated (removal of the acetyl group) prior to absorption it can readily be reacetylated afterwards.[38] Alterations in this transporter, such as its increase in states of carnitine deficiency[51] or its impairment in persons with Celiac disease who are not on a gluten-free diet (and normalization upon switching to a gluten free diet[52]) determine alterations in L-carnitine absorption.

L-Carnitine is absorbed in the gut via the OCTN2 transporter, and alterations in this transporter determine alterations in L-carnitine absorption. If it is increased, then more is absorbed, if it is impaired or blocked, then less L-carnitine is absorbed

Carnitine in food sources tends to have higher bioavialability (54-87%) than supplementation of L-Carnitine at 14-18%.[53][4]This general trend of much lower bioavailability from supplementation holds true for Acetyl-L-Carnitine (lower bioavailability than food sources)[4] and studies in animals suggest it would hold true for Propionyl-L-carnitine or PLC.[54] When comparing the various forms of Carnitine, there are studies noting better absorption with L-carnitine relative to ALCAR[48] and the opposite[55][4] although the isomer of D-Carnitine does not appear to be absorbed at all.[38]

When examining variations in the absorption of L-carnitine, it seems that L-carnitine found in food products is absorbed to a better degree than L-carnitine from supplements (regardless of the form used), but supplements are still absorbed to a fairly decent degree

Intradermal delivery of L-Carnitine has been shown to increase bioavailability as much as 2.8x in rats, although this number is subject to vary depending on vehicle and pretreatment.[56]



I want to increase the absorption of the orally taken supplement