when to take BCAA+EAA in regards to mTOR?

[Aleksandar37]

Ignoring the building block idea of BCAAs and EAAs and just thinking of their affect upon mTOR to boost protein synthesis, when would be the most ideal time to take them?
-Pre-workout?
-Intra-workout?
-Post-workout?
-All of the above?

 

[tnubs]

between meals, first thing in the morning. have u read layne nortons article on leucine?

 

[rms80]

Ignoring the building block idea of BCAAs and EAAs and just thinking of their affect upon mTOR to boost protein synthesis, when would be the most ideal time to take them?
-Pre-workout?
-Intra-workout?
-Post-workout?
-All of the above?

All of the above- but preferentially post- here are links to some of the pathways:
J Nutr. 2006 Jan;136(1 Suppl):269S-73S.

Branched-chain amino acids activate key enzymes in protein synthesis after physical exercise.
Blomstrand E, Eliasson J, Karlsson HK, Köhnke R.

Department of Surgical Science, Karolinska Institutet, Stockholm, Sweden. [email protected]

Abstract
BCAAs (leucine, isoleucine, and valine), particularly leucine, have anabolic effects on protein metabolism by increasing the rate of protein synthesis and decreasing the rate of protein degradation in resting human muscle. Also, during recovery from endurance exercise, BCAAs were found to have anabolic effects in human muscle. These effects are likely to be mediated through changes in signaling pathways controlling protein synthesis. This involves phosphorylation of the mammalian target of rapamycin (mTOR) and sequential activation of 70-kD S6 protein kinase (p70 S6 kinase) and the eukaryotic initiation factor 4E-binding protein 1. Activation of p70 S6 kinase, and subsequent phopsphorylation of the ribosomal protein S6, is associated with enhanced translation of specific mRNAs. When BCAAs were supplied to subjects during and after one session of quadriceps muscle resistance exercise, an increase in mTOR, p70 S6 kinase, and S6 phosphorylation was found in the recovery period after the exercise with no effect of BCAAs on Akt or glycogen synthase kinase 3 (GSK-3) phosphorylation. Exercise without BCAA intake led to a partial phosphorylation of p70 S6 kinase without activating the enzyme, a decrease in Akt phosphorylation, and no change in GSK-3. It has previously been shown that leucine infusion increases p70 S6 kinase phosphorylation in an Akt-independent manner in resting subjects; however, a relation between mTOR and p70 S6 kinase has not been reported previously. The results suggest that BCAAs activate mTOR and p70 S6 kinase in human muscle in the recovery period after exercise and that GSK-3 is not involved in the anabolic action of BCAAs on human muscle.

J Nutr. 2006 Jan;136(1 Suppl):264S-8S.

Branched-chain amino acids as fuels and anabolic signals in human muscle.
Rennie MJ, Bohé J, Smith K, Wackerhage H, Greenhaff P.

Medical Sciences, University of Aberdeen, Aberdeen AB24 3FX, UK. [email protected]

Abstract
During exercise, there is an increase in amino acid (AA) oxidation accompanied by a depression in whole-body protein synthesis and an increase in protein breakdown. Leucine oxidation increases in proportion to energy expenditure, but the total contribution of BCAA to fuel provision during exercise is minor and insufficient to increase dietary protein requirements. When investigating the effects of AA on the control of muscle protein synthesis (MPS), we showed that increased availability of mixed AAs caused a rise in human MPS to about the same extent as complete meals. Leucine alone (and to some extent other essential, but not nonessential, AAs) can stimulate MPS for a short period, suggesting that leucine acts as a signal as well as a substrate. MPS stimulation by infused AAs shows tachyphylaxis, returning to basal rates after 2 h, possibly explaining why chronically elevated leucine delivery does not elevate MPS clinically. Increased availability of essential amino acids (EAAs) results in dose-related responses of MPS, but, in elderly subjects, there is blunted sensitivity and responsiveness associated with decreased total RNA and mRNA for signaling proteins and signaling activity. Increases of MPS due to EAAs are associated with elevation of signaling activity in the mammalian target of rapamycin (mTOR)/p70 ribosomal subunit S6 kinase eukaryotic initiation factor 4 binding protein 1 pathway, without requiring rises of plasma insulin availability above 10 microU/mL. However, at insulin of <5 microU/mL, AAs appear to stimulate MPS without increasing mTOR signaling. Further increasing availability of insulin to postprandial values increases signaling activity, but has no further effect on MPS.

 

[rms80]

Am J Physiol Regul Integr Comp Physiol. 2007 Sep;293(3):R1335-41. Epub 2007 Jun 20.

Exercise training increases branched-chain oxoacid dehydrogenase kinase content in human skeletal muscle.
Howarth KR, Burgomaster KA, Phillips SM, Gibala MJ.

Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada.

Abstract
The branched-chain oxoacid dehydrogenase complex (BCOAD) is rate determining for the oxidation of branched-chain amino acids (BCAAs) in skeletal muscle. Exercise training blunts the acute exercise-induced activation of BCOAD (BCOADa) in human skeletal muscle (McKenzie S, Phillips SM, Carter SL, Lowther S, Gibala MJ, Tarnopolsky MA. Am J Physiol Endocrinol Metab 278: E580-E587, 2000); however, the mechanism is unknown. We hypothesized that training would increase the muscle protein content of BCOAD kinase, the enzyme responsible for inactivation of BCOAD by phosphorylation. Twenty subjects [23 +/- 1 yr; peak oxygen uptake (.VO(2peak)) = 41 +/- 2 ml.kg(-1).min(-1)] performed 6 wk of either high-intensity interval or continuous moderate-intensity training on a cycle ergometer (n = 10/group). Before and after training, subjects performed 60 min of cycling at 65% of pretraining .VO(2peak), and needle biopsy samples (vastus lateralis) were obtained before and immediately after exercise. The effect of training was demonstrated by an increased .VO(2peak), increased citrate synthase maximal activity, and reduced muscle glycogenolysis during exercise, with no difference between groups (main effects, P < 0.05). BCOADa was lower after training (main effect, P < 0.05), and this was associated with a approximately 30% increase in BCOAD kinase protein content (main effect, P < 0.05). We conclude that the increased protein content of BCOAD kinase may be involved in the mechanism for reduced BCOADa after exercise training in human skeletal muscle. These data also highlight differences in models used to study the regulation of skeletal muscle BCAA metabolism, since exercise training was previously reported to increase BCOADa during exercise and decrease BCOAD kinase content in rats (Fujii H, Shimomura Y, Murakami T, Nakai N, Sato T, Suzuki M, Harris RA. Biochem Mol Biol Int 44: 1211-1216, 1998).

Go to this link for the whole enchilada in terms of the pathway:
http://www.cellsignal.com/reference/pathway/images/mTor.jpg

 

[rms80]

J Pediatr Endocrinol Metab. 2010 Jul;23(7):641-50.

Effect of HMB supplementation on body composition, fitness, hormonal profile and muscle damage indices.
Portal S, Eliakim A, Nemet D, Halevy O, Zadik Z.

Ribstein Center for Sport Medicine Sciences and Research, Wingate Institute, Netanya, Israel. [email protected]

Abstract
There is a huge market for ergogenic supplements for athletes. However, only a few products have been proven to have ergogenic effects and to be effective at improving muscle strength and body composition. One such supplement is beta-hydroxy beta-methylbutyrate (HMB). Derived from the amino acid leucine and its keto acid alpha-ketoisocaproate (KIC), HMB has been well documented as an oral ergogenic supplement commonly used by athletes. Several studies have shown that combining exercise training with HMB supplementation leads to increased muscle mass and strength, and there is some anecdotal evidence of aerobic improvement. However, HMB supplementation has been found to be effective mainly for untrained individuals. While previous reviews have emphasized three main pathways for HMB's mode of action: 1) enhancement of sarcolemmal integrity via cytosolic cholesterol, 2) inhibition of protein degradation via proteasomes, and 3) increased protein synthesis via the mTOR pathway, more recent studies have suggested additional possible mechanisms for its physiological effects. These include decreased cell apoptosis and enhanced cell survival, increased proliferation, differentiation and fusion via the MAPK/ERK and PI3K/Akt pathways, and enhanced IGF-I transcription. These are described here, and hormonal interactions are discussed, along with HMB dosage and safety issues.


J Pediatr Endocrinol Metab. 2010 Jul;23(7):641-50.

Effect of HMB supplementation on body composition, fitness, hormonal profile and muscle damage indices.
Portal S, Eliakim A, Nemet D, Halevy O, Zadik Z.

Ribstein Center for Sport Medicine Sciences and Research, Wingate Institute, Netanya, Israel. [email protected]

Abstract
There is a huge market for ergogenic supplements for athletes. However, only a few products have been proven to have ergogenic effects and to be effective at improving muscle strength and body composition. One such supplement is beta-hydroxy beta-methylbutyrate (HMB). Derived from the amino acid leucine and its keto acid alpha-ketoisocaproate (KIC), HMB has been well documented as an oral ergogenic supplement commonly used by athletes. Several studies have shown that combining exercise training with HMB supplementation leads to increased muscle mass and strength, and there is some anecdotal evidence of aerobic improvement. However, HMB supplementation has been found to be effective mainly for untrained individuals. While previous reviews have emphasized three main pathways for HMB's mode of action: 1) enhancement of sarcolemmal integrity via cytosolic cholesterol, 2) inhibition of protein degradation via proteasomes, and 3) increased protein synthesis via the mTOR pathway, more recent studies have suggested additional possible mechanisms for its physiological effects. These include decreased cell apoptosis and enhanced cell survival, increased proliferation, differentiation and fusion via the MAPK/ERK and PI3K/Akt pathways, and enhanced IGF-I transcription. These are described here, and hormonal interactions are discussed, along with HMB dosage and safety issues.

Biochem Biophys Res Commun. 2002 Dec 20;299(5):693-6.

Leucine promotes glucose uptake in skeletal muscles of rats.
Ni****ani S, Matsumura T, Fujitani S, Sonaka I, Miura Y, Yagasaki K.

Pharmaceutical Research Laboratories, Ajinomoto Co., Inc., 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa 210-8681, Japan. shinobu_ni****[email protected]

Abstract
Soleus muscles isolated from normal rats were incubated to evaluate whether or not leucine promotes glucose uptake under insulin-free conditions, using a labeled 2-deoxyglucose uptake assay. Glucose uptake was promoted by 2mM leucine. A metabolite of leucine, alpha-ketoisocaproic acid (alpha-KIC), also exhibited a similar stimulatory effect, although this was not as potent as leucine. Stimulation of glucose uptake by leucine was completely canceled by pre-treatment with either 10 microM LY294002, a specific inhibitor of phosphatidylinositol 3-kinase (PI3-kinase), or 6 microM GF109203X, a specific inhibitor of protein kinase C (PKC). No significant change was observed by pre-treatment with 1 microM rapamycin, a specific inhibitor of mammalian target of rapamycin (mTOR). These results suggest that leucine stimulates glucose transport in skeletal muscle via PI3-kinase and PKC pathways independently of the mammalian target of mTOR. They also suggest that leucine stimulates glucose transport by an insulin-independent mechanism.

 

[rms80]

There are also some interesting sub-pathways that mTOR, once stimulated, will upregulate...

 

[nattydisaster]

Ignoring the building block idea of BCAAs and EAAs and just thinking of their affect upon mTOR to boost protein synthesis, when would be the most ideal time to take them?
-Pre-workout?
-Intra-workout?
-Post-workout?
-All of the above?

http://www.usplabsdirect.com/catalog/product_info.php?products_id=123

Best summarized mTOR info I have read is the Modern BCAA writeup

 

[Aleksandar37]

Thanks to all!!!