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PubMed2005

[Effect of branch chain amino acid enriched formula on postoperative fatigue and nutritional status after digestive surgery].

OBJECTIVE: To evaluate the effect of branch chain amino acid (BCAA) enriched formula on nutritional status and postoperative fatigue for digestive surgery patients. METHODS: Forty patients who underwent digestive surgery were randomly received parenteral nutrition with either BCAA enriched (study group, n=20) or routine amino acid (control group, n=20) for seven consecutive days. Nitrogen balance,serum total protein, albumin, prealbumin, transferrin, retinol binding protein and postoperative fatigue score were monitored during the postoperative period. RESULTS: The cumulative postoperative fatigue scores were lower in BCAA group than that in the control group at the 4th, 5th and 7th day after operation (P< 0.05). Patients achieved positive nitrogen balance 2 days earlier in the study group than that in the control group, but there was no significant difference in cumulative nitrogen balance between the two groups. There was no significant difference in elevation of serum total protein, albumin, prealbumin, transferrin at the 7th day after operation between the two groups (P > 0.05), compared with those at the first day after operation. The serum level of retinol binding protein was higher in BCAA-enriched group than that in the control group (P=0.004). CONCLUSION: TPN with BCAA enriched formula can reduce postoperative fatigue score and improve the nutritional status for digestive surgery patients.

Adult↗
PubMed1991

Leucine dose response in the reduction of urea production from septic proteolysis and in the stimulation of acute-phase proteins.

The administration of branched-chain amino acids (BCAAs) has been proved useful in reducing both urea nitrogen production and muscle proteolysis in trauma patients with sepsis, but the optimum infusion rate to achieve these effects is still in question. In this prospective randomized study, a group of 16 posttrauma patients with sepsis received a branched chain-enriched (BCAA = 49.4%) amino acid mixture (8 patients; 120 observations) or a standard amino acid infusion (BCAAs = 15.5%; 8 patients; 227 observations). Total calories, percent lipid calories, and amino acid nitrogen administration were not different in the two groups. Each patient was studied at 8-hour intervals for the plasma levels of amino acids, six hepatic acute-phase proteins, albumin, and other metabolic parameters, including urinary urea nitrogen and 3-methylhistidine excretion. The total intake of each amino acid and its clearance were calculated and the dose of leucine during each 8-hour period was related to the leucine clearance, plasma acute-phase protein levels, and the urinary production of urea and 3-methylhistidine, as an indicator of proteolysis. The results show a significant (r2 = 0.691; p less than 0.0001) reduction of urea nitrogen production and proteolysis as a function of the increase in leucine dose. The identification of a critical mean rate of leucine infusion has been derived from the analysis of the significant linear correlation between leucine intake and leucine clearance (r2 = 0.594; p less than 0.0001). Significant positive correlations between the leucine intake dose and the platelet count (r2 = 0.402; p less than 0.0001), the plasma fibrinogen level (r2 = 0.218; p less than 0.0001), and the regression-derived sum of six acute-phase proteins plus albumin (r2 = 0.696; p less than 0.0001) were found. The increase in leucine clearance was progressively less marked above a mean daily leucine intake rate of 1.4 mumol/kg/min, which also appeared to be the dose level that maximized the acute-phase protein and coagulation effects and reduced proteolysis and urea nitrogen production, suggesting that this is a critical BCAA infusion rate at which an optimum leucine effect occurs. From these data a BCAA (leucine) dose nomogram has been derived.

Acute-Phase Proteins↗
PubMed1991

[The effect of various compositions of TPN on nutritional and immunological assessment in patients with esophageal cancer].

The purpose of this clinical study was to determine 1) whether high calorie diet gives any advantages for nutritional assessment and immunological functions after esophagectomy, 2) whether BCAA is useful to improve immunological parameters postoperatively and 3) which energy source is mainly utilized, fat or glucose, postoperatively. To accomplish the purpose of this study, three experiments were carried out. The subjects were 210 patients with esophageal cancer. Exp. 1: Either high (over 40kcal/kg/day) or low (under 35kcal/kg/day) calorie diet was administered postoperatively. Exp. 2: 30% BCAA versus 22.6% BCAA diet was compared under high calorie diet. Exp. 3: 24% fat versus 13% fat diet was compared, giving high calorie diet with 30% BCAA. Nutritional assessment was done by postoperative performance nutritional index, fatty acid analysis, energy expenditure, nitrogen balance and A-V difference of alanine and glutamine, and also immunological function by PHA, lymphocytes, NK activity of lymphocyte and leu 7 positive cells. Regardless of composition of TPN, high calorie diet improved nutritional assessment and immunological functions. A-V difference and fat combustion were improved with high fat diet in postoperative courses. It was concluded that high calorie diet with 30% BCAA and 24% fat was beneficial after esophagectomy.

Aged↗
PubMed1989

[A study on amino acid solutions for postoperative parenteral nutrition--evaluation in terms of surgical stress, amino acid composition and its doses].

A newly composed amino acid solution, which contained a 30% branched-chain amino acid (BCAA), and a standard amino acid solution containing 22.6% BCAA were used for total parenteral nutrition following operation of the digestive organs. Their nutritional effects were evaluated by surgical stress (thoracotomy group or non-thoracotomy group) according to the two steps of amino acid doses (1.2g/kg/day administration group or 1.6g/kg/day group). 1. No significant differences could be recognized in an improvement in the serum proteins following administration of BCAA-enriched solution either in the thoracotomy or in the non-thoracotomy group. 2. An improvement in BCAA/AAA molar ratio was seen on the plasma aminogram following administration of BCAA-enriched solution both in the thoracotomy and in the non-thoracotomy groups. 3. No improvement in nitrogen balance following administration of BCAA-enriched solution could be found in the thoracotomy group, while its improving trend was recognized in the non-thoracotomy group treated with 1.6g/kg/day of the amino acid. 4. Neither in the thoracotomy nor in the non-thoracotomy group any significant inhibition of the excreted volumes of urinary 3-methylhistidine could be recognized.

Amino Acids, Branched-Chain↗
PubMedDate not supplied

Effects of small variations in insulin and glucagon levels on plasma aminoacids concentrations.

To determine the effect in normal subjects of small variations of insulin and glucagon on plasma aminoacids concentrations we suppressed endocrine pancreas secretion with somatostatin and measured aminoacids levels during a sequential insulin infusion in the absence (control test, low glucagon level) or in the presence (normal glucagon concentration) of a replacement glucagon infusion. Insulin infusion rates were 0.05, 0.09, 0.15 and 0.30 mU.kg-1.min-1 during the control test and 0.09, 0.15, 0.30 and 0.40 mU.kg-1.min-1 during the replacement test. During the control test, glucagon decreased (p less than 0.01) and insulin levels were successively 8.2 +/- 0.4, 10.1 +/- 0.7, 11.9 +/- 0.14 and 18.5 +/- 0.8 mU.l-1. The only effect on insulin was to decrease branched-chain aminoacids (BCAA). BCAA were inversely related to insulinemia (p less than 0.01). A significant decrease was obtained for an insulin level of 11.9 +/- 0.4 mU.l-1, a value intermediate between those decreasing glycerol (10.1 +/- 0.7 mU.l-1) and stimulating total body glucose uptake (18.5 +/- 0.8 mU.l-1). During the test with glucagon replacement glucagon was maintained at its initial value. Insulin levels were successively 8.3 +/- 0.3, 11.9 +/- 0.3, 19.7 +/- 0.6 and 26.7 +/- 0.5 mU.l-1. Insulin decreased always BCAA but also threonine, proline, tyrosine, methionine and total aminoacid levels. BCAA were always inversely related to insulin levels (p less than 0.01) but the slope of the relationship was modified and more insulin was needed to decrease BCAA concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Effects of supplementation with branched-chain amino acids on protein-nutritional status in rats treated by carbon tetrachloride].

A study was conducted to investigate effects of oral supplementation with branched-chain amino acids (BCAA) on protein-nutritional status in rats with liver cirrhosis. Liver cirrhosis was induced in male strain Sprague-Dawley rats by simultaneously administrating carbon tetrachloride (500 mg/kg, twice a week, intracutaneously) and phenobarbital (0.05% in drinking water, ad libitum) for 30 weeks. Following treatment with carbon tetrachloride and phenobarbital, cirrhotic rats received oral supplementation of BCAA with varying ratio among isoleucine (Ile), leucine (Leu) and valine (Val), or with varying content of total BCAA in the diet (Final content of total nitrogen was kept consistent by addition of glutamine). Nutritional efficacies of diets as described above were evaluated employing those protein-nutritional parameters as nitrogen balance and plasma levels of total protein, albumin and free neutral amino acids. Following results were obtained: 1. Compositional ratio of Ile:Leu:Val at 1:2:1.2 or at 2:1:1 was found to be more effective on diets which contained ILe:Leu:Val at 1:1:2 or either Val, Ile or Leu alone. 2. As to content of total BCAA in the diet (0, 2.5, 5, 10%), supplementation level of 2.5% was found to be most appropriate in terms of effects on nitrogen balance and on plasma protein concentration. In conclusion, 2.5% BCAA in the diet with the ratio of Ile:Leu:Val at 1:2:1.2 or 2:1:1 seems to be recommended to improve the impaired protein-nutritional status in liver cirrhosis.

Amino Acids, Branched-Chain↗
PubMed1985

Infusion of branched-chain amino acids and ammonium salts in rats with portacaval shunts.

During infusion into rats with a portacaval shunt of either ammonium (NH4+) salts alone or NH4+ salts combined with the three branched-chain amino acids (BCAAs) in equimolar quantities, we assessed neurologic function and measured plasma and brain ammonia and amino acid levels and the brain content of amine neurotransmitters and their metabolites. Survival was lengthened and neurologic function was preserved longer in rats receiving BCAAs. Infusion of BCAAs resulted in lower plasma and brain ammonia concentrations compared with rats receiving NH4+ salts alone. Plasma glutamine and alanine levels were higher in rats receiving BCAAs, suggesting increased ammonia detoxification. Loss of neurologic function, regardless of which solution was infused, eventually occurred and corresponded with decreased brain norepinephrine and increased brain alanine levels. These results suggest that BCAAs can protect against hyperammonemia by stimulating the peripheral detoxification of ammonia.

Amino Acids, Branched-Chain↗
PubMed1988

Evaluation of parenteral nutrition in the postoperative patient.

A variety of investigators have attempted to improve nitrogen balance during the postoperative period by modifying the composition of the infused nutrient solutions. This study compared the metabolic effects of administering standard amino acid solutions with a solution enriched with branched chain amino acids (BCAA). A prospective, randomized clinical study was performed in patients who had undergone subtotal gastrectomy or hemicolectomy, and subsequently cared for in the metabolic care unit. The patients were selected from specific entry criteria so that two groups of individuals were comparable. All patients underwent operation without complications. The plasma concentrations of valine and leucine were significantly increased (p less than 0.05 and p less than 0.01, respectively) two days after administration of solutions enriched with BCAA and throughout the entire postoperative period. The plasma glutamine concentrations tended to decrease in both groups; no concentration difference occurred between groups. Nitrogen balance tended to be more positive in the group receiving BCAA but there was no significant difference between groups after operation. Urinary excretion of 3-methylhistidine tended to increase postoperatively in both groups, but no difference occurred between groups. However, the urine excretion of isoleucine increased significantly in the patients receiving infusions enriched with BCAA. Both standard balanced amino acid and amino solutions enriched with BCAA were well tolerated in all patients.

Amino Acids, Branched-Chain↗
PubMed1988

[Metabolic and nutritional support in severely burned patients].

UNLABELLED: Proper metabolic and nutritional support is an important treatment modality in severely burned patients. We examined the effect of branched-chain amino acid (BCAA) enriched TPN on metabolism of burned rats. A scald injury (30% BSA) was produced in rats. The rats, after resuscitated with saline for 24 hr, were divided into 3 groups. CONTROL GROUP: received saline. Group B: received TPN with BCAA enriched solution (45% BCAA). Group C: received TPN with conventional amino acid solution (21.3% BCAA). Both of these TPN solutions were isocaloric and isonitrogenous. Rats of each group were administered TPN solution or saline for further 48 hr. The metabolites in the liver and muscle were measured. Rapid and marked decrease of levels of metabolites such as adenine nucleotides, glycogen, G-6-P, protein and RNA/DNA was observed in the liver and muscle of the rats during fluid resuscitation. The rats of group B showed significant recoveries in all of these parameters after administration of the TPN, as compared with those of group C. On the other hand, progressive metabolic deterioration was recognized in the rats of control group. These results indicate beneficial effects of BCAA enriched TPN on energy and protein metabolism in scald injury.

Amino Acids, Branched-Chain↗
PubMed1988

Comparative metabolism of branched-chain amino acids to precursors of juvenile hormone biogenesis in corpora allata of lepidopterous versus nonlepidopterous insects.

Comparative studies were performed on the role of branched-chain amino acids (BCAA) in juvenile hormone (JH) biosynthesis using several lepidopterous and nonlepidopterous insects. Corpora cardiaca-corpora allata complexes (CC-CA, the corpora allata being the organ of JH biogenesis) were maintained in culture medium containing a uniformly 14C-labeled BCAA, together with [methyl-3H]methionine as mass marker for JH quantification. BCAA catabolism was quantified by directly analyzing the medium for the presence of 14C-labeled propionate and/or acetate, while JHs were extracted, purified by liquid chromatography, and subjected to double-label liquid scintillation counting. Our results indicate that active BCAA catabolism occurs within the CC-CA of lepidopterans, and this efficiently provides propionyl-CoA (from isoleucine or valine) for the biosynthesis of the ethyl branches of JH I and II. Acetyl-CoA, formed from isoleucine or leucine catabolism, is also utilized by lepidopteran CC-CA for biosynthesizing JH III and the acetate-derived portions of the ethyl-branched JHs. In contrast, CC-CA of nonlepidopterans fail to catabolize BCAA. Consequently, exogenous isoleucine or leucine does not serve as a carbon source for the biosynthesis of JH III by these glands, and no propionyl-CoA is produced for genesis of ethyl-branched JHs. This is the first observation of a tissue-specific metabolic difference which in part explains why these novel homosesquiterpenoids exist in lepidopterans, but not in nonlepidopterans.

Amino Acids, Branched-Chain↗
PubMed1985

Failure of branched-chain amino acids to affect synaptosomal uptake of norepinephrine and dopamine.

Despite evidence for neuroendocrine actions of the branched-chain amino acids (BCAAs) and implications that these amino acids alter the turnover of central catecholamines, the mechanism of these actions of the BCAAs is uncertain. In this study, we tested the effects of the BCAAs on uptake of catecholamines by axon terminals (synaptosomes) isolated from whole mouse brain minus the cerebellum. Neither high physiological (1-2 mM) nor pharmacological levels (10 mM) of an equimolar mixture of the BCAAs altered the uptake of 3H-dopamine and 3H-norepinephrine by synaptosomes. These findings suggest that the BCAAs do not influence the reuptake mechanism for termination of catecholamine-mediated neurotransmission.

Amino Acids, Branched-Chain↗
PubMed1983

Branched-chain amino acid metabolism in chronic renal failure.

Interorgan exchange of branched-chain amino acids (BCAA) in the postabsorptive state was evaluated in 16 patients with chronic renal failure (CRF) and in 20 subjects with normal renal function, by measuring arterial-venous differences of BCAAs across the leg, brain, hepato-splanchnic (HS) bed, and kidney. In CRF, arterial blood levels of valine are significantly reduced, whereas leucine and isoleucine levels are not different from controls; valine and leucine levels are directly related to GFR. In CRF, a significant decrease in the release of valine by the leg is observed; the leucine release tends to be lower; for both these amino acids, leg release is directly related to their arterial levels. Both ratios of valine and leucine release to total amino acid release by the leg are significantly reduced in CRF. Furthermore, in CRF cerebral uptake and fractional extraction of valine and isoleucine are decreased. In normal subjects, valine and leucine are significantly extracted by the HS bed, whereas in CRF the HS uptake of valine and its fractional extraction fall significantly and leucine uptake is unchanged. The kidney releases significant amounts of leucine both in CRF and in controls. In conclusion, in CRF in the postabsorptive state the exchange of BCAAs, mainly valine, is altered rather early at the major sites of production and utilization, and the flux of these amino acids among the organs is decreased. The primary defect is the decreased output by peripheral tissue, which reduces the supply of BCAAs to the brain and HS bed. Regional metabolic disturbances further impair BCAA utilization.

Adult↗
PubMed1983

In vitro adsorption spectrum of plasma amino acids by coated charcoal hemoperfusion.

In order to clarify whether coated charcoal hemoperfusion is capable of normalizing amino acid disturbances in hepatic coma, in vitro adsorption and in vitro hemoperfusion studies were carried out. We have found that collodion-coated activated charcoal beads preferentially removed much more aromatic acids (AAA) than branched chain amino acids (BCAA). In the in vitro adsorption experiment with 50 microM amino acid standards aqueous solution, 99% of AAAs were removed by charcoal while only 50 to 81% of BCAAs were removed. As the concentration of amino acids in solution was doubled from microM to 100 microM, BCAA removal was halved while about 90% of AAA was still being removed. In vitro hemoperfusion with heparinized blood from hepatic failure rats, the clearance and the removal of AAAs were significantly greater than those of BCAAs. Consequently, the molar ratio of BCAA over AAA was markedly improved from the initial 1.09 to 3.87 after 60 min of hemoperfusion. Thus, we have demonstrated the preferential adsorption of aromatic amino acids by collodion-coated charcoal beads. The correction of BCAA/AAA molar ratio is also demonstrated.

Adsorption↗
PubMed1982

Branched chains support postoperative protein synthesis.

A blinded, prospective trial of the effects of branched-chain amino acid (BcAA)-enriched total parenteral nutrition (TPN) versus standard TPN was undertaken in nonseptic noncirrhotic abdominal surgery patients and patients with multiple traumatic injuries. The study reflected data from the immediate 7-day postoperative period. With isocaloric and isonitrogenous input, the BcAA-TPN patients achieved positive nitrogen balance on day 3. Although the urinary nitrogen output was decreased by day 3 in BcAA-TPN, the plasma BcAA levels did not increase until day 6. With no change in 3-methylhistidine urinary excretion, the early nitrogen retention with BcAA-TPN probably reflects a stimulation of protein synthesis. The ability to favorably modulate the metabolic stress response with alternate fuels has become a clinical reality.

Adult↗
PubMed1982

The effect of a new branched chain--enriched amino acid solution on postoperative catabolism.

Branched-chain amino acids (BCAAs) may regulate muscle amino acid flux. Metabolic studies of both experimental animals and humans utilizing comparatively large amounts of BCAAs infused with hypocaloric glucose have shown that catabolism and proteolysis can be blunted. These studies suggested that the nitrogen-sparing properties of amino acid solutions used in postoperative trauma or sepsis might be improved by increasing the amount of BCAAs. This hypothesis was tested on ten patients undergoing operations of moderate severity utilizing a peripheral amino acid mixture with a branched-chain:non-branched-chain ratio of 45:55% given in 5% dextrose. The patients received 1.7 gm of protein equivalent/kg of ideal body weight in 5% dextrose-crystalloid solution with a concentration of 3.5% amino acids for the first 5 postoperative days. Nitrogen balance, 3-methylhistidine excretion, blood chemistries, and plasma amino acid profile tests were done daily. The results showed that nitrogen equilibrium was maintained for 5 postoperative days without any untoward effects on patients, their surgical wounds, or hepatic function. Plasma amino acids showed no significant changes from baseline with the exception of elevations of the BCAAs. We conclude that this 45% BCAA-enriched solution may be safely administered to patients with postoperative traumatic injury and results in nitrogen equilibrium over a 5-day period.

Adolescent↗
PubMed1994

Precursor role of branched-chain amino acids in the biosynthesis of iso and anteiso fatty acids in rat skin.

Monoester fraction of rat skin surface lipid has been shown to contain more than trace amounts of branched-long-chain fatty acids (BCFAs) of the iso and anteiso series. These BCFAs are biosynthesized using either branched-chain amino acids (BCAAs) or branched-chain alpha-keto acids (BCKAs), or using both of them as precursor. This study has been carried out to address which precursor, BCAAs or BCKAs in the circulation, are mainly utilized for biosynthesis of BCFAs. Dietary supplement of [14C]-valine and isoleucine-induced sharp rise of serum concentration of these two amino acids and their respective alpha-keto acids, and elevated the levels of related BCFAs and branched-chain fatty alcohols in the monoester fraction. A larger proportion of label in the total skin surface lipid was found in the monoester fraction in which fatty acid and alcohol accounted for approx. 80% of total radioactivity. Incorporation of intravenously administered [14C]-BCAAs and BCKAs into the monoester fraction revealed that BCAAs were far better as precursors than BCKAs for BCFA biosynthesis in rat skin. Among three BCAAs, leucine differed from valine or isoleucine in that this amino acid was primarily utilized for production of straight-chain fatty acids rather than for production of related BCFA.

Amino Acids, Branched-Chain↗
PubMedDate not supplied

Branched-chain amino acids and respiratory pattern and function in the neonate.

Branched-chain amino acids (BCAA) increase respiratory drive in adults and improve diaphragmatic function in vitro. This study was designed to examine the effects of increased amounts of BCAA in intravenous nutrition on respiratory function and episodes of apnea in premature infants. An open cross-over design was used, with each patient serving as his own control. Ten premature infants, 34 weeks' gestation or less, were observed. Mean gestational age was 30.6 weeks (range 27 to 33 weeks), mean birth weight was 1487 gm +/- 300 gm, and the age at study was 5 to 33 days. For three consecutive 24-hour periods, the infants received routine total parenteral nutrition (TPN) (30% BCAA), enriched TPN (53% BCAA), and routine TPN (30% BCAA). Pulmonary function, apnea frequency, blood chemistry, and amino acid pattern were measured. Enriched TPN resulted in significant increases in all infants in dynamic compliance, from 2.41 +/- 1.07 to 4.55 +/- 2.78 ml/cm H2O (p < 0.025), and in specific dynamic compliance from 1.67 +/- 0.64 to 3.1 +/- 1.51 ml/cm H2O/kg (p < 0.005). Total pulmonary resistance decreased from 40.3 +/- 23.3 to 24.0 +/- 20.9 cm H2O/L/sec (p < 0.05), and peak-to-peak pressure decreased from 5.96 +/- 0.93 to 4.09 +/- 2.34 cm H2O (p < 0.05). All values returned to baseline with resumption of the routine TPN. In four infants with significant apnea, the average number of episodes of apnea decreased from 58 during standard TPN to 11 with the enriched solution infusion during matched 12-hour periods (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed1993

Peripheral metabolism of branched-chain keto acids in patients with chronic renal failure.

Peripheral tissue metabolism of branched-chain amino acids (BCAA) and branched-chain keto acids (BCKA) in the postabsorptive state was evaluated in 8 patients with chronic renal failure (CRF) and 7 controls by measuring the arterial-deep forearm venous differences for BCAA and BCKA. Arterial whole blood levels of BCAA and BCKA were also measured in an additional 7 patients and 11 controls. In CRF, total BCKA levels are reduced owing to a decrease in ketoisocaproic acid (KICA) and ketoisovaleric acid (KIVA) levels, parallel to changes in BCAA levels, whereas levels of ketomethylvaleric acid (KMVA) are not different from controls. Both in normal conditions and in patients, arterial levels of individual BCAA are directly correlated with arterial levels of the corresponding BCKA. However, in CRF, the ratios of leucine to KICA and of isoleucine to KMVA are increased. A direct correlation between KICA and HCO3- levels is observed. In CRF, the release of leucine and valine as well as of KICA and KMVA from peripheral tissues is reduced, whereas KIVA is neither released nor taken up by the forearm. The lack of KICA release from peripheral tissues likely accounts for its low circulating levels. The depressed peripheral release of leucine associated with the lack of KICA release suggests an increased degradation of leucine which proceeds beyond the transamination step.

Adult↗