Glutamine with water

[Slugger]

Is it ok to mix glutamine with water or is it best to mix it with something like gatorade?

Right now I'm mixing with water 10 g post workout and 10 g before bed.

[RP7]

You dont need a sugar (like dextrose) to spike your insulin for glutamine. Just take it on an empty stomach so you can get good absorption. If you want to mix it, go nuts.

[Brazy]

i've been told taking glutamine on an empty stomach goes towards restoring glycogen..

i've been told its best to take it 15 min after a meal.. and thats what i've done and it seems to does it part well

and i mix 5g with a glass of water

[Blackac]

So whats the rule of thumb with glutamine, 3000mg before the work out and 3000mg after workout....and on an empty stomach......i have capsules..

[Elliot]

caps are horrible its a total rip off.. get protein powder that already has it.. www.allthewhey.com for example..

[Valmont]

Glutamine peptides. preferbly on empty stomach after morning cardio.

Ice is a pretty good supplement as well. or you could check with macphage on here, he will hook you up.

[baller45]

I have a different opinion about oral glutamine, since the small intestine uses it all for energy.

"Oral is useless for what most want it to do. Take a dipeptide if you want to see it work. "-Animal

[K-pac]

slugger,

I don't think that you need to take 20g of glutamine a day. I think 5-10g post workout should suffice. Correct me if I am wrong guys.
K-pac

[daman1]

slugger,

I don't think that you need to take 20g of glutamine a day. I think 5-10g post workout should suffice. Correct me if I am wrong guys.
K-pac

You are correct. I would take 5g's p.w. and 5g's before bedtime.

[baller45]

No. If you take whey you are getting enough already. I can't stand peole wasting money. Can anyone actually tell me that extra free-form glutamine does anthing but get sucked up by the small intestine? No, you can't.

[RP7]

No. If you take whey you are getting enough already. I can't stand peole wasting money. Can anyone actually tell me that extra free-form glutamine does anthing but get sucked up by the small intestine? No, you can't.

Then don't take it. Let us all waste our money in peace. And why don't you enlighten us with your knowledge since we cant prove anything.

[baller45]

Then don't take it. Let us all waste our money in peace. And why don't you enlighten us with your knowledge since we cant prove anything.

Hehe!
Here...

[baller45]

The entire piece was written because of free form glutamine's lack of effectiveness.

New Developments in Glutamine Delivery1
Peter Fürst2

University of Hohenheim, Institute for Biological Chemistry and Nutrition, Stuttgart, Germany



2To whom correspondence should be addressed. E-mail: [email protected]




ABSTRACT
TOP
ABSTRACT
INTRODUCTION
Dipeptide concept
Glutamine dipeptides: a new...
Implications for glutamine...
Alternative nitrogen-containing...
LITERATURE CITED


Numerous studies demonstrate that free glutamine can be added to commercially available crystalline amino acid-based preparations before their administration. Instability during heat sterilization and prolonged storage and limited solubility (35 g/L at 20°C) hamper the use of free glutamine in the routine clinical setting. Indeed, there are many well-controlled and valuable trials with free glutamine, yet its use is restricted to clinical research. The obvious limitations of using free glutamine initiated an intensive search for alternative substrates. Synthetic glutamine dipeptides are stable under heat sterilization and highly soluble; these properties qualify the dipeptides as suitable constituents of nutritional preparations. Industrial production of these dipeptides at a reasonable price is an essential prerequisite for implications of dipeptide-containing solutions in clinical practice. Recent development of novel synthesis procedures allows increased capacity in industrial-scale production. Basic studies with synthetic glutamine-containing short-chain peptides provide convincing evidence that these new substrates are cleared rapidly from plasma after parenteral administration, without being accumulated in tissues and with negligible loss in urine. The presence of membrane-bound as well as tissue-free extracellular hydrolase activity facilitates a prompt and quantitative peptide hydrolysis, the liberated amino acids being available for protein synthesis and/or generation of energy. In the clinical setting, glutamine dipeptide nutrition beneficially influences outcome (nitrogen balance, immunity, gut integrity, hospital stay, morbidity and mortality). The provision of conditionally indispensable glutamine should be considered a necessary replacement of a deficiency rather than a supplementation. The beneficial effects observed with glutamine dipeptide nutrition should be seen simply as a correction of disadvantages produced by the inadequacy of conventional clinical nutrition. The availability of stable dipeptide preparations certainly facilitates, for the first time, adequate amino acid nutrition of critically ill, malnourished or stressed patients in the routine clinical setting and, thus, represents a new dimension in artificial nutrition.


Key Words: glutamine dipeptides • ornithine -ketoglutarate • acetylated amino acids • short chain protein hydrolysates • catabolic stress


INTRODUCTION
TOP
ABSTRACT
INTRODUCTION
Dipeptide concept
Glutamine dipeptides: a new...
Implications for glutamine...
Alternative nitrogen-containing...
LITERATURE CITED


Available data strongly support the notion that glutamine should be an essential part of parenteral nutrition in various diseased states (Wilmore and Shabert 1998 , Fürst et al. 2000a, Griffiths 1999 ). However, two unfavorable physical chemical properties prevent the inclusion of free glutamine in commercially available amino acid preparations; the quantitative decomposition of aqueous glutamine to the cyclic product associated with ammonia liberation (Fürst et al. 1990 ) and its limited solubility in water (35 g/L H2O at 20°C). Therefore, glutamine-containing TPN solutions must be prepared freshly under strict aseptic conditions and stored at 4°C. To diminish the risk of precipitation, the glutamine concentration in such solution should not exceed 2.5%. This means that provision of adequate amounts of glutamine to injured or critically ill patients represents a severe burden, especially in volume-restricted situations. Consequently, parenteral use of free glutamine is reserved for controlled clinical trials and only in countries allowing nonheat-sterilized solutions.

Controlled clinical studies with free glutamine showed improved nitrogen balance and rate of protein synthesis (Griffiths 1999 , Hammarqvist et al. 1989 , Ziegler et al. 1992 , Li et al. 1997 ) compared with control groups. Post-bone marrow transplantation morbidity was reduced with supplemental glutamine; the incidence of clinical infection, total and site-specific microbial colonization and the length of hospital stay were reduced compared with control groups (Hammarqvist et al. 1989 , Schloerb and Amare 1993 ). A recent clinical study demonstrated reduced 6-mo mortality in critically ill patients with a decrease in treatment costs, comparing glutamine-enriched parenteral nutrition with isonitrogenous isocaloric controls (Griffiths et al. 1997 ).


Dipeptide concept
TOP
ABSTRACT
INTRODUCTION
Dipeptide concept
Glutamine dipeptides: a new...
Implications for glutamine...
Alternative nitrogen-containing...
LITERATURE CITED


The obvious limitations of using glutamine in its native form have initiated an intensive search for amino acid sources and precursors. Indeed, dipeptides are perfect candidates. Their use shows great promise as a method for provision of glutamine, which is otherwise difficult to deliver.

The dipeptides with glutamine at the C-terminal position, fulfill all chemical and physical criteria needed for approval by the authorities for composition of parenteral solutions.

Synthesis and characterization of dipeptides with special reference to glutamine containing dipeptides.
In the early 1980s, dipeptides were not commercially available. Thus, the first task was to synthesize suitable dipeptides on a laboratory scale and attempt a purity of >99%, high water solubility, stability during heat sterilization and storage. In early trials, we used a modified N-carboxy anhydride method for the synthesis of a great variety of peptides in acceptable yields (Stehle et al. 1982 ). Confirmation of the structure of the purified peptides was achieved via mass spectroscopy and nuclear magnetic resonance spectroscopy. Great efforts were made to obtain reliable data concerning peptide purity. We established a novel free-flow electrophoretic technology (analytical isotachophoresis) enabling simultaneous determination of organic and inorganic impurities in the purified peptide material (Stehle et al. 1986 ). The combined use of this highly specific method with reverse-phase HPLC techniques showed purity degrees > 99% for the synthetic peptides. Interestingly, the peptides synthesized revealed solubilities in aqueous solutions 20- to 2000-fold higher than the corresponding free amino acids (Table 1). Heat stability under strictly controlled conditions at 121°C over 30 min was confirmed by heat stability of glutamine and tyrosine peptides (Stehle et al.1982 ). Under these conditions, the cystine-containing peptides showed less stability, yet still retained sufficient stability during sterile filtration to be considered parenteral substrates.




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Table 1. Chemical/physical characteristics of selected free amino acids and synthetic short chain peptides




Indeed, using the N-carboxy anhydride method, glutamine-, tyrosine- and cystine-containing dipeptides could be synthesized, yet formation of side products and polymerization reactions diminished product yields and made subsequent purification difficult. Consequently, there was an obvious need for better techniques. As a potential alternative to traditional peptide synthesis procedures, biotechnological approaches using native or immobilized enzymes as biocatalysts have been advocated by peptide chemists. It has been known since the beginning of the 20th century that the protease-catalyzed hydrolysis of peptide bonds is generally reversible. However, it took >50 y until the potentials of this method were recognized and further developed (Konopinska and Muzalewski 1983 , Jakubke et al. 1985 ). The obvious advantages of an enzyme-catalyzed peptide synthesis are the (stereo)-specificity of the reaction, the possibility to minimize protection of functional groups and the feasibility to use free amino acids as nucleophiles. The principle of the kinetic approach using serine or sulfhydryl proteases in aqueous medium is schematically shown in Figure 1 . These enzymes exhibit both hydrolase and esterase activities. In alkaline aqueous solutions, the N-protected amino acid esters (electrophiles) rapidly form the intermediate acyl-enzyme complex. This complex is attacked by nucleophiles, either by water (hydrolysis) or by an amine (aminolysis, e.g., a free amino acid). If k4 (H2N-R) is higher than k3 (H2O), the corresponding N-protected dipeptide is accumulated in the reaction medium. Besides the nucleophile concentration, the ratio aminolysis/hydrolysis additionally can be influenced by pH in the medium reaction temperature and the ratio of nucleophile to electrophile.




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Figure 1. Schematic illustration of enzyme-catalyzed peptide synthesis (kinetic approach). R-COOX = N-acyl amino acid ester (electrophile); H-E = serine or sulfhydryl protease; H2-N-R = amino acid or derivative thereof; R-CO-E = acyl-enzyme complex. From Fürst et al. 1997a with permission from S. Karger AG, Basel, Switzerland.




By using commercially available plant (ficin and papain) and animal (chymotrypsin) proteases, we synthesized a great variety of peptide precursors in high yields (Table 2; Stehle et al. 1990 , Monter et al. 1991 ). The use of selectively cleavable N-protecting group (e.g., carbobenzoxy-, formyl-, maleyl-) facilitates an easy and effective liberation of the desired unprotected dipeptide, e.g., simply by acidification of the reaction mixture. After deprotection, the desired dipeptide could be almost quantitatively isolated in high purity (Monter et al. 1991 ).



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Table 2. Enzyme-catalyzed synthesis of dipeptide precursors




The prerequisite for a commercial realization of this biotechnological approach is the development of a continuous process. In current studies, we attempted ficin-catalyzed synthesis of the N-protected dipeptide N-carbobenzoxy-L-alanyl-L-glutamine (Cbz-Ala-Gln) using enzyme membrane reactors (reactor volume 10 and 130 mL, respectively; Bahsitta 1993 ). The flow diagram of the experimental system is shown in Figure 2 . The native enzyme is retained in the reactor using an ultrafiltration membrane. Substrate solution 1 (0.2 mol/L Gln, 8 mmol/L EDTA, pH 9.2) was continuously pumped (5–10 mL, residence time: 90 min) through a sterile filter into the thermostatic (30°C) reactor. Before entering the reactor, the glutamine solution was adjusted to pH 9.3–9.5 to maintain an effluent pH of 9.2. Substrate solution 2 (1 mmol/L of the electrophile Cbz-Ala-Ome in EtOH) was periodically added to the reaction mixture every 3 h for 60 min (flow rate: 0.5 mL/h). The reaction was started by adding 100 mg ficin dissolved in water; loss of enzyme activity over time was compensated by periodic addition of 100-mg portions of the enzyme. The mean process time was 60 ± 25 h. At this time, the product yields an average of 45% of theory, which is not yet sufficient to compete with traditional industrial procedures. The results are sufficiently encouraging to justify additional biotechnological approaches for chemical dipeptide synthesis.




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Figure 2. Flow diagram of the enzyme membrane reactor system. SS1, substrate storage 1; SS2, substrate storage 2 (electrophile); PP, peristaltic pump; TC, titration cell; SF, sterile filter; P, pressure gauge; BT, bubble trap; CSTR, continuously stirred tank reactor (volume 10 mL or 130 mL); PS, product storage. From Fürst et al. 1997a , with permission from S. Karger AG, Basel, Switzerland.





Glutamine dipeptides: a new dimension in clinical nutrition
TOP
ABSTRACT
INTRODUCTION
Dipeptide concept
Glutamine dipeptides: a new...
Implications for glutamine...
Alternative nitrogen-containing...
LITERATURE CITED


Preparations.
The glutamine containing dipeptides L-alanyl-L-glutamine (Ala-Gln) and glycyl-L-glutamine are available products and today are an integral part of routine clinical practice. These preparations, Dipeptiven and Glamin (Fresenius Kabi, Uppsala, Sweden), are innovative products; the result of many years of intensive research in the field of clinical nutrition. Dipeptiven is a 20% solution of the glutamine-containing dipeptide N(2)-L-alanyl-L-glutamine (Ala-Gln). It is stable during heat sterilization and storage, and it is highly soluble (568 g/L; Table 1 ). Glamin is a complete, well-balanced amino acid solution containing 30.27 g/L stable glycyl-L-glutamine (Gly-Gln). Basic studies in humans and animals provide firm evidence that both glutamine dipeptides are readily used. Importantly, infusion of Dipeptiven or Glamin is well tolerated and not accompanied by any side effects or complaints. The dipeptide concept is based upon the premise that improvement in the quality of available amino acid solutions, currently lacking glutamine, is a major step in resolving the problem of how to formulate and prepare a complete, well-balanced amino acid solution.

Implications for glutamine dipeptide therapy
TOP
ABSTRACT
INTRODUCTION
Dipeptide concept
Glutamine dipeptides: a new...
Implications for glutamine...
Alternative nitrogen-containing...
LITERATURE CITED


Glutamine can be considered a conditionally indispensable amino acid during stress. It is of great importance to formulate guidelines for routine clinical dipeptide nutrition, identifying areas such as:

which biochemical indications

which patients

how much

when to start administration

which route of administration

Biochemical indications.
Generally, poor nutritional status as assessed by body weight, body mass index, anthropometric measures and low plasma albumin, and severe loss of nitrogen and functional tissue, is a useful indication for glutamine dipeptide therapy. Poor immune status is always a strong signal of glutamine deprivation. Decreased body cell mass, in combination with decreased intracellular and increased extracellular water (easily measured via bioimpedance spectroscopy), favor glutamine dipeptide administration. Please note that plasma-free glutamine concentrations do not always reflect body glutamine status. A normal plasma glutamine level might be associated with severe intracellular glutamine depletion.

Patients.
Glutamine (dipeptide) nutrition is an important therapeutic measure in a number of clinical situations. Table 3 suggests patient categories that may benefit from glutamine dipeptide therapy.




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Table 3. Patient groups that may benefit from glutamine dipeptide therapy




Timing and route of administration.
Administration of glutamine by the intravenous route is the most reliable method of achieving a prolonged constant elevation of the free glutamine pool of the body. Supplemental intravenous glutamine dipeptides exert numerous beneficial effects as summarized in Table 4 . Glutamine dipeptides should be provided immediately after the catabolic insult to initially support the attenuated tissues with glutamine.



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Table 4. Effects of glutamine dipeptide supplemented parenteral nutrition: clinical trials




At present, there is much controversy concerning the benefit of enteral glutamine nutrition (Fürst 2000b ). In many available studies no convincing biologic or clinical results were obtained from traumatized or intensive care unit (ICU)3 patients despite considerable supply of glutamine (15–35 g/d; Table 5 ).



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Table 5. Enteral glutamine: clinical studies




To date, tube-feeding trials show that hypocaloric glutamine-supplemented enteral diets will not provide the requisite amounts of glutamine that can escape the splanchnic bed to elevate blood and muscle concentrations. The reasons for the unfavorable results with enteral glutamine supplementation are multifactorial. Theoretically, the presence of bacterial overgrowth in stressed patients might in part explain the observed low circulating glutamine concentrations, because it is well known that bacteria readily consume glutamine as a preferred substrate. It is also possible that splanchnic glutamine use may contribute to the inability of glutamine-enriched enteral feeds to increase the plasma glutamine levels. Glutamine is absorbed in the upper part of the small intestine and subsequently metabolized in the liver, and, thus, it may not be available in sufficient quantity for the target mucosal tissue at the lower sites of the intestine (Fürst 2000b ) .
It is notable that enteral glutamine nutrition, which initially did not raise the blood glutamine concentration, has been shown to improve the outcome in premature infants; for example, the frequency of sepsis decreased and immunity increased after 0.3 g/kg body enteral supplementation of glutamine (Neu et al. 1997 ). These beneficial effects presumably reflect increased bowel maturation, indicating that enteral glutamine can act on the gastrointestinal tract without exerting direct systemic effects (Wilmore and Shabert 1998 ). In adult patients, glutamine has been shown to have a beneficial effect on intestinal barrier function when given orally (30 g/d) for several weeks after high dose chemotherapy or radiotherapy for esophageal cancer (Yoshida et al. 1998 ).

Another confirmation that enteral glutamine is effective in preventing infective complications has been recently reported in 60 patients with severe multiple trauma (Houdijk et al. 1998 ). There was a significant reduction (50%) in the 15-d incidence of pneumonia, bacteremia and severe sepsis. The strengths of this study are in the relatively homogeneous population of patients studied and the fact that the study did not suffer from the confounding factors present in multicenter studies. The results of this fascinating study require confirmation.

There is some evidence that the body glutamine pool is slower to recover when the same dose of glutamine is given enterally (orally) as opposed to parenterally (Fish et al. 1997 ). The enteral route may be ideal when given early to the noninfected patient to improve gut-associated lymphoid tissue function and immune defense against infection, but for already severely stressed or infected ICU patients, enteral supplements alone may be inadequate, and parallel parenteral support is likely to be required. It has been clearly shown that during intensive care parenteral supplementation of enteral nutrition with glutamine does not increase the risk to the patients and may ensure a better overall outcome (Bauer et al. 1998 ). It should, however, be borne in mind that enteral supplementation with glutamine is a potential hazard because such formulations may form a vigorous cultural medium for microorganisms if strict care is not taken (Griffiths 1999 ).

Dosing of glutamine dipeptides.
It is generally accepted that a 60- to 70-kg patient after major injury, uncomplicated elective surgery, with gastrointestinal malfunctions or cachexia, should be given 18–30 g glutamine dipeptides (13–20 g glutamine/d). A severely injured patient with multiple injury, burns, sepsis, systemic inflammatory response syndrome, serious immune deficiency, as well as after bone marrow transplant, may require higher doses of glutamine dipeptide (Wilmore and Shabert 1998 , Griffiths 1999 , Wilmore 1997 , Wilmore et al. 1999 , Fürst et al. 2000b ).

Indeed, lack of glutamine from conventional TPN and its subsequent supplementation should be considered as a correction of a deficiency rather than as supplementation (Griffiths 1999 , Fürst et al. 1997b ) and as a novel therapeutical measure using glutamine as a pharmacon (pharmacological nutrition). Thus, it is conceivable that the beneficial effects observed with glutamine dipeptide nutrition are simply a correction of disadvantages produced by inadequacies of conventional amino acid solutions. The availability of stable glutamine-dipeptide-containing preparations (Dipeptiven and Glamin) now facilitates glutamine nutrition in routine clinical settings.


Alternative nitrogen-containing substrates
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ABSTRACT
INTRODUCTION
Dipeptide concept
Glutamine dipeptides: a new...
Implications for glutamine...
Alternative nitrogen-containing...
LITERATURE CITED


N-acetylated amino acids.
The implication of N-acetylated amino acids was an early suggestion to facilitate parenteral provision of cysteine, tyrosine and glutamine. Early studies in experimental rats undergoing long-term TPN clearly have shown that highly soluble and stable N-acetylated amino acids, acetylcysteine, acetyltyrosine and acetylglutamine, are rapidly taken up and are subsequently hydrolyzed by acylases after their parenteral administration (Neuhäuser et al. 1985 , 1986 , 1988 ). In a subsequent study in dogs, Abumrad et al. (1989 ) observed only poor use of parenterally supplied acetylglutamine associated with a large urinary excretion (38% of the amount infused). Among the organs studied, only the kidney cleared acetylglutamine to a measurable extent. This was confirmed in healthy humans because continuous infusion of acetylglutamine (Magnusson et al. 1989a ), acetyltyrosine or acetylcysteine (Magnusson et al. 1989b ) resulted in an accumulation of the respective compound in plasma in which levels of the corresponding free amino acids were not, or only slightly, increased (Fig. 3 ). The urinary excretion rate of the acetylated amino acids approached 40–50% of the amount given. After bolus injection of acetyltyrosine, Druml et al. (1991 ) observed little if any hydrolysis of the acetylated amino acid. Pharmacokinetic evaluation after intravenous supply of acetyl-cysteine in humans exhibited an elimination half-life of 2.3 h, a value which is indeed 40-fold higher than values observed for cystine-containing peptides (Stehle et al. 1988 ).





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Figure 3. Human plasma concentration of acetylglutamine (AcGln), acetyltyrosine (AcTyr) and acetylcysteine (AcCys) before and during intravenous infusion of AcGln, AcTyr and AcCys, respectively. (Modified from Magnusson et al. 1989a and 1989b ).




It can be concluded that N-acetylated amino acids are poorly used in humans due to restricted acylase capacities except for in the kidneys.
Short-chain protein hydrolysates.
Purified short-chain protein hydrolysates (>67% di- and tripeptides, >10% free amino acids) have been discussed as a low osmolality alternative to free amino acid solutions and synthetic dipeptides for peripheral parenteral nutrition (Grimble and Silk 1989 , Grimble et al. 1992 ). In an enzymatically prepared short-chain casein hydrolysate, < 10% of those amino acids that are themselves relatively insoluble or unstable (tyrosine, cysteine, glutamine, tryptophan) were found to exist in free form (Grimble et al. 1987 ).

During intravenous infusion of a short-chain ovalbumin hydrolysate in healthy human subjects, excess peptide excretion suggested that a large proportion of the hydrolysate was metabolized (Grimble et al. 1988 ). Marked differences between infused and excreted peptide profiles indicated that use of peptides from the hydrolysate was sequence-specific.

Ornithine -ketoglutarate (OKG).
The salt OKG might exert a synergistic effect on both its constituents. Recent investigations suggest that after enteral OKG administration gut morphology and function improve, trauma-induced immune dysfunction is alleviated and there are anabolic /anticatabolic actions on protein metabolism (Cynober 1995 , 1999 ). Because the majority of these studies were performed in various experimental models, it is necessary to confirm the postulated benefits in controlled clinical trials. Theoretically, the properties of OKG should counteract the catabolic response that occurs during episodes of infection and after trauma and injury. Enteral administration has been proposed in various catabolic situations (Cynober 1999 ). Favorable effects on muscle protein synthesis have been observed in trauma and burned patients after enteral administration (Cynober 1999 , Le Bricon et al. 1997 ), and improved N-balance and protein synthesis have been found after intravenous administration (Hammarqvist et al. 1991 ). However, direct beneficial effects of ornithine or OKG on gut structure, function or outcome have not been demonstrated (Gardiner et al. 1995 ). Therefore, any clinical impact of the findings outlined above requires confirmation by additional controlled studies (Jolliet et al. 1999 ).

There are numerous underlying mechanisms proposed that might account for the observed beneficial effects of OKG, including glutamine formation, arginine, proline, polyamine generation, increase in growth hormone and insulin secretion, etc. A principal question is whether OKG is a true precursor for glutamine. According to textbooks, KG is the precursor of glutamic acid, although its precursor function for glutamine is limited. Accordingly, several reports demonstrate that the in vivo transformation from external glutamic acid to glutamine is restricted, corresponding to not > 5–6% of the given dose (Darmaun et al. 1986 ). Certainly labeled KG might be recovered in tissue glutamine (Vaubourdolle et al. 1988 ), yet this finding does not reflect the extent of transformation in a quantitative manner. Human stable-isotope studies confirm that continuous enteral delivery of labeled KG or OKG cannot alter glutamine kinetics in burned patients (Mittendorfer et al. 1999 ). Because glutamic acid is known to be poorly transported across the cell membrane, it can be concluded that KG or related compounds cannot replace glutamine in clinical nutrition unless KG is directly taken up by cells and converted first to glutamic acid and subsequently to glutamine. This theoretical pathway, however, has not yet been established (Fürst et al. 1999 ).

Adequate delivery of glutamine in the frame of artificial nutrition is an important measure to support healing and reduce morbidity and mortality of stressed patients. Certain clinical conditions are accompanied with characteristic alterations in organ-specific glutamine metabolism. Because the requirement exceeds the availability of glutamine, it should be ranked as conditionally indispensable and, thus, should be a mandatory part of nutritional measures. Apart from its nutritive role, glutamine possesses certain pharmacologic and/or immunologic effects. Clinical studies reveal evidence that the currently applied concept of glutamine nutrition is beneficial in providing patients with a conditionally indispensable amino acid that is otherwise difficult to deliver.

Among novel ways to deliver glutamine (glutamine dipeptides, acetylglutamine, short-chain protein hydrolysates and OKG), the glutamine dipeptide approach is the most promising. This compilation may well illustrate how far we have advanced our knowledge of the importance of a new substrate in modern artificial nutrition. There is little question that efforts made to modify the response to disease by glutamine nutrition will be rewarded with improved patient outcome.



FOOTNOTES

1 Presented at the International Symposium on Glutamine, October 2–3, 2000, Sonesta Beach, Bermuda. The symposium was sponsored by Ajinomoto USA, Inc. The proceedings are published as a supplement to The Journal of Nutrition. Editors for the symposium publication were Douglas W. Wilmore, the Department of Surgery, Brigham and Women’s Hospital, Harvard Medical School and John L. Rombeau, the Department of Surgery, the University of Pennsylvania School of Medicine.

3 Abbreviations used: ICU, intensive care unit; OKG, ornithine -ketoglutarate.

[baller45]

LITERATURE CITED
TOP
ABSTRACT
INTRODUCTION
Dipeptide concept
Glutamine dipeptides: a new...
Implications for glutamine...
Alternative nitrogen-containing...
LITERATURE CITED




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[baller45]

so...

[RP7]

Holy ****! You just solved the great glutamine debate. Tell all the mods! We have the answer! We found the study! Glutamine is useless! Burn the church!

[decadbal]

i hate when ppl paste something thats half a mile long, if you already read it, give us the short of it, or just post the site link..... the more glut u take a day the more you absorb, you also waste more as well, but you still can take as much as you like really.

[daman1]

caps are horrible its a total rip off.. get protein powder that already has it.. www.allthewhey.com for example..

also agree. but some dont give adequate amounts, and some have none at all.

[Scrapper]

5 gram postw & 5 gram before bed seems to work fine for me..

[daman1]

Just keep this in mind. If you are taking in protein drinks each day, then there is most likely no need for glutamine. But if your not, then get some...

[RP7]

Just keep this in mind. If you are taking in protein drinks each day, then there is most likely no need for glutamine. But if your not, then get some...

True. Glutamine is manufactured in your body from amino acids I believe. Or you can be like me and have glutamine mixed in your protein.

[baller45]

i hate when ppl paste something thats half a mile long, if you already read it, give us the short of it, or just post the site link..... the more glut u take a day the more you absorb, you also waste more as well, but you still can take as much as you like really.

I would have but you don't have access to the site its from.
I wish someone would have read the study. It says that a peptide like l-alanyl-l-glutamine is something that would give you the benefits your looking for from normal glutamine. The get sucked away by your intestine. Unless you are sick. People who are ill are able to get benifits from free form glutamine.

Glutamine is manufactured in your body from amino acids I believe.

Yep it's synthesized from glutamate and glutamic acid by glutamate-ammonia ligase. Thats why a good protein shake is enough.

[RP7]

Unless you are sick. People who are ill are able to get benifits from free form glutamine.

Now you seem to be somewhat contradicting yourself. Since intense workouts depress the immune system albeit temporarily and also reduce glutamine stores, then how is free form glutamine not beneficial for us all?

[baller45]

Now you seem to be somewhat contradicting yourself. Since intense workouts depress the immune system albeit temporarily and also reduce glutamine stores, then how is free form glutamine not beneficial for us all?

I didn't mean a temp drop in the immune system. I mean so bad that the absorbtion of the free form is due to the body own surival mechanism kicking in. Anyway, a good protein shake will be plenty to top off your stores.
Those studies that use hospital patients are very commonly used by supplement companies to push the benefits of free form. You just got to check up on their references to see just what group of people got those results.

The worst is when they will site studies about that methoxy stuff.
They are almost all completley done on geriatrics.