Between Branched-chain Amino Acids Research Articles

Associations between sarcopenia and circulating branched-chain amino acids: a cross-sectional study over 100,000 participants

BackgroundEmerging evidence suggests that alterations in BCAA metabolism may contribute to the pathogenesis of sarcopenia. However, the relationship between branched-chain amino acids (BCAAs) and sarcopenia is incompletely understood, and existing literature presents conflicting results. In this study, we conducted a community-based study involving > 100,000 United Kingdom adults to comprehensively explore the association between BCAAs and sarcopenia, and assess the potential role of muscle mass in mediating the relationship between BCAAs and muscle strength.MethodsMultivariable linear regression analysis examined the relationship between circulating BCAAs and muscle mass/strength. Logistic regression analysis assessed the impact of circulating BCAAs and quartiles of BCAAs on sarcopenia risk. Subgroup analyses explored the variations in associations across age, and gender. Mediation analysis investigated the potential mediating effect of muscle mass on the BCAA-muscle strength relationship.ResultsAmong 108,017 participants (mean age: 56.40 ± 8.09 years; 46.23% men), positive associations were observed between total BCAA, isoleucine, leucine, valine, and muscle mass (beta, 0.56–2.53; p < 0.05) and between total BCAA, leucine, valine, and muscle strength (beta, 0.91–3.44; p < 0.05). Logistic regression analysis revealed that increased circulating valine was associated with a 47% reduced sarcopenia risk (odds ratio = 0.53; 95% confidence interval = 0.3–0.94; p = 0.029). Subgroup analyses demonstrated strong associations between circulating BCAAs and muscle mass/strength in men and individuals aged ≥ 60 years. Mediation analysis suggested that muscle mass completely mediated the relationship between total BCAA, and valine levels and muscle strength, partially mediated the relationship between leucine levels and muscle strength, obscuring the true effect of isoleucine on muscle strength.ConclusionThis study suggested the potential benefits of BCAAs in preserving muscle mass/strength and highlighted muscle mass might be mediator of BCAA-muscle strength association. Our findings contribute new evidence for the clinical prevention and treatment of sarcopenia and related conditions involving muscle mass/strength loss.

Causal Relationship Between Branched-Chain Amino Acids and Hypertension: AMendelian Randomization Study.

This study aimed to investigate the causal relationships between branched-chain amino acids (BCAAs) and the risks of hypertension via meta-analysis and Mendelian randomization analysis. A meta-analysis of 32 845 subjects was conducted to evaluate the relationships between BCAAs and hypertension. In Mendelian randomization analysis, independent single-nucleotide polymorphisms associated with BCAAs at the genome-wide significance level were selected as the instrumental variables. Meanwhile, the summary-level data for essential hypertension and secondary hypertension end points were obtained from the FinnGen study. As suggested by the meta-analysis results, elevated BCAA levels were associated with a higher risk of hypertension (isoleucine: summary odds ratio, 1.26 [95% CI, 1.08-1.47]; leucine: summary odds ratio, 1.28 [95% CI, 1.07-1.52]; valine: summary odds ratio, 1.32 [95% CI, 1.12-1.57]). Moreover, the inverse variance-weighted method demonstrated that an elevated circulating isoleucine level might be the causal risk factor for essential hypertension but not secondary hypertension (essential hypertension: odds ratio, 1.22 [95% CI, 1.12-1.34]; secondary hypertension: odds ratio, 0.96 [95% CI, 0.54-1.68]). The increased levels of 3 BCAAs positively correlated with an increased risk of hypertension. Particularly, elevated isoleucine level is a causal risk factor for essential hypertension. Increased levels of leucine and valine also tend to increase the risk of essential hypertension, but further verification is still warranted.

An integrated analysis of transcriptome and metabolome reveals three BCAAs relieve lipid accumulation by inhibiting lipid synthesis and promoting lipid oxidation in the liver of largemouth bass (Micropterus salmoides)

The intricate and paradoxical relationship between branched-chain amino acids (BCAAs) and lipid metabolism has been focused on the field of nutrition. However, the molecular mechanism mediated by BCAAs in the lipid metabolism of fish is poorly understood. To address this knowledge gap, we characterized the transcriptome and metabolome in the liver of largemouth bass (Micropterus salmoides), an extensively cultivated fish with high commercial value. Dietary BCAA supplementation significantly enhanced growth performance, combined with the elevation of essential amino acid levels and the improvement of liver health. Moreover, enzymatic detection and RT–qPCR results showed that BCAAs decreased lipid deposition in the liver. Integrated transcriptomics and metabolomics analysis revealed that the inhibition of lipid synthesis and enhancement of fatty acid degradation may explain the mechanism by which BCAAs relieved lipid accumulation in the liver. The metabolic enzymes acaca, acaa2, cpt2, acat, and aldh9a1, which were regulated by all three BCAAs, are key targets linking BCAA metabolism and lipid metabolism. Considering that farmed fish suffer from abnormal lipid accumulation in the liver, appropriate BCAA supplementation is an effective nutritional strategy to improve lipid metabolism disorders in aquaculture.

The relationship between the intake of branched-chain and aromatic amino acids and individuals' sleep quality based on body mass index, gender, and age

Sleep disorder is a relatively common problem that causes chronic conditions such as obesity, diabetes, and cardiovascular diseases. It is believed that diet regulates sleep. So, investigating the relationship between branched-chain amino acids (BCAAs) and aromatic amino acids intake with sleep quality based on age, gender and Body Mass Index (BMI) is important. A total of 172 males and females aged 18–65 participated in this study. The questionnaires were given online to them, included demographic information, food frequency questionnaire (FFQ), International Physical Activity Questionnaire, and Pittsburgh Sleep Quality Index. The Chalder fatigue scale (CFQ) was also used to measure the extent and severity of fatigue. The intake of amino acids was investigated by FFQ. The relationship between amino acids intake and sleep quality was investigated using Pearson's test. The results showed that intake of energy, macronutrients, and some micronutrients had a significant relationship with the quality of sleep of men compared to that of women (P < 0.05). No difference in sleep duration was observed between the two genders. There was a significant, positive association between sleep duration and the intake of BCAA (CC = 0.205, P = 0.031) and aromatic amino acids (CC = 0.22, P = 0.02) in the participants with normal BMI. Significant differences were seen in the intake of BCAA according to BMI which these differences were between lean and obese people, lean and overweight people, obese and normal, and overweight people. It demonstrated that in individuals with normal BMI, amino acids, protein, and carbohydrate intake may affect sleep duration and with modification of these factors sleep quality may get better. More study is needed to confirm these findings.

Chronic supplementation of branched chain amino acids and its impact on glucose and hepatic metabolism during insulin sensitivity

Dysfunctional interactions between branched chain amino acids (BCAAs) and facets of glucose and lipid metabolism are central features of insulin resistant tissues. However, it is unclear whether insulin resistance is a prerequisite for the biochemical relationships between BCAAs and macronutrient networks. We hypothesize that BCAAs will enhance glucose and lipid oxidation, lower gluconeogenesis and decrease hepatic de novo lipogenesis to optimize insulin sensitivity. Male mice (C57BL/6NJ) were placed on either a low-fat (LF; 10% fat Kcal) or LF supplemented with 1.5X BCAAs (LB) diet for a period of 12-32 wks. Oxygen consumption and energy expenditure were determined by indirect calorimetry after 12 and 24-wks on the diets. After 32-wks on the diets and a 4-hr fast, LF and LB mice underwent intraperitoneal glucose tolerance test (IPGTT) with the 2g/kg glucose containing 50% [ 13 C 6 ]glucose. Blood glucose was measured every 15-min and blood was collected every 30-min for 2 hours. Enrichment of 13 C from glucose into pyruvate and other metabolic intermediates was determined by gas-chromatography and mass-spectrometry (GC-MS). Following 1-wk of recovery, these LF and LB mice were randomly split into fed and overnight fasted groups. [ 13 C 3 ] pyruvate (20 mg) was injected intraperitoneally to determine the rate of incorporation of pyruvate into glucose via. gluconeogenesis, utilizing GC-MS. Hepatic gene expression in fed and fasted livers were profiled using qPCR. Supplementation of BCAAs for 24-wks increased energy expenditure and oxygen consumption in the LB mice vs. their LF counterparts (p≤0.05). Additionally, IPGTT revealed improved insulin sensitivity in LB mice vs. their LF counterparts (p&lt;0.05). Dilution of [ 13 C 6 ]glucose was lower in the LB plasma by the 90-min time point of the glucose tolerance test (% enrichment; LB; 16.42±0.74 vs. LF; 18.06±0.54, p=0.09), while the LB blood glucose levels during IPGTT remained lower, indicative of higher rates of glucose oxidation in LB mice. Further, following the pyruvate tolerance test, incorporation of [ 13 C 3 ]pyruvate into glucose tended to be higher in the fasted BCAA supplemented group (% enrichment; LB; 11.79±0.23 vs. LF; 10.58±0.53, p=0.07). Basal levels of tricarboxylic acid (TCA) cycle intermediates in plasma were significantly different between LF vs. LB mice (p&lt;0.05). Fed-to-fasted fold induction of genes involved in lipid oxidation ( Lcad, P para) were higher in the LB livers vs. their LF counterparts (p≤0.05). On the contrary, fed-to-fasted suppression of lipogenic gene expression (A cc, F as) was greater in the LB livers vs. their LF counterparts (p&lt;0.05). In summary, our results indicate that chronic BCAA supplementation to insulin sensitive mice positively impacts aspects of glucose and lipid metabolism. The ability of BCAAs to modulate macronutrient metabolism could have beneficial effects in alleviating metabolic dysfunction during early stages of insulin resistance and fatty liver disease. National Institute of Health R01DK112865 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Camellia (Camellia oleifera Abel.) Seed Oil Regulating of Metabolic Phenotype and Alleviates Dyslipidemia in High Fat-Fed Mice through Serum Branch-Chain Amino Acids.

Camellia (Camellia oleifera Abel.) seed oil (CO) has been shown to effectively reduce the blood lipid level of its host due to its fatty acid content, but the specific molecular mechanism associated with the metabolic phenotype after digestion is not clear. Here, we further investigated the relationship between branched-chain amino acids (BCAA) and the metabolic phenotype that may exhibit the anti-dyslipidemia effect of CO on mice fed a high-fat diet for 30 day C57BL/6J male mice were allocated to three groups: the control group (Cont), the high-fat feed group (HFD), and a high-fat feed group with CO treatment (CO). A serum sample was collected to detect lipid biomarkers and BCAA concentration. Notably, Low-density lipoprotein (LDL), Total Cholesterol (TC), and Triglycerides (TG) showed a significant decrease, whereas High-density lipoprotein (HDL) increased in CO mice but not in the HFD group. The concentration of Isoleucine (Ile), leucine (Leu), and valine (Val) was similar between the Cont and CO groups compared with the HFD group, exhibiting an inhibition induced by CO in mice fed with a high-fat diet. A metabolic phenotype from serum examined by non-targeted metabolite analysis using UHPLC/MS showed most metabolites exhibited lipid and BCAA metabolism. The results indicated that CO treatment notably regulated the metabolism of arachidonic acid and steroid biosynthesis in response to HFD-induced dyslipidemia. In addition, the expression of PPARγ genes that correlated with the BCAA and serum lipid biomarkers were compared, and significant inhibition was noticed, which might lead to the potential exposure of the anti-dyslipidemia mechanism of CO in HFD-fed mice. In conclusion, the expression of PPARγ genes, serum lipid level, BCAA concentration, and the metabolic phenotype was significantly positive in correlation with a high-fat diet, whereas oral CO improved the biomarkers and metabolism of some specific serum metabolites in HFD-fed mice.

BCAA-BCKA axis regulates WAT browning through acetylation of PRDM16.

The link between branched-chain amino acids (BCAAs) and obesity has been known for decades but the functional role of BCAA metabolism in white adipose tissue (WAT) of obese individuals remains vague. Here, we show that mice with adipose tissue knockout of Bcat2, which converts BCAAs to branched-chain keto acids (BCKAs), are resistant to high-fat diet-induced obesity due to increased inguinal WAT browning and thermogenesis. Mechanistically, acetyl-CoA derived from BCKA suppresses WAT browning by acetylation of PR domain-containing protein 16 (PRDM16) at K915, disrupting the interaction between PRDM16 and peroxisome proliferator-activated receptor-γ (PPARγ) to maintain WAT characteristics. Depletion of BCKA-derived acetyl-CoA robustly prompts WAT browning and energy expenditure. In contrast, BCKA supplementation re-establishes high-fat diet-induced obesity in Bcat2 knockout mice. Moreover, telmisartan, an anti-hypertension drug, significantly represses Bcat2 activity via direct binding, resulting in enhanced WAT browning and reduced adiposity. Strikingly, BCKA supplementation reverses the lean phenotype conferred by telmisartan. Thus, we uncover the critical role of the BCAA-BCKA axis in WAT browning.

The Association between Branched-Chain Amino Acids (BCAAs) and Cardiometabolic Risk Factors in Middle-Aged Caucasian Women Stratified According to Glycemic Status.

We examined the glycemic status-stratified relationships between total serum branched-chain amino acid (BCAA) concentrations and cardiometabolic risk factors in middle-aged Caucasian women. The study included 349 women divided into 2 subgroups: a normoglycemic group (NG, n = 184) and a dysglycemic group (DG, n = 165). Blood samples, anthropometric parameters, and blood pressure were measured. HOMA-IR, albumin-corrected calcium (CCa), and fatty liver index (FLI) were calculated. BCAA concentrations were higher in the women with dysglycemia. BCAAs moderately correlated with BMI and FLI in the NG group and with BMI, FLI, total calcium (TCa), CCa, HbA1c, TG/HDL-C, and HDL-C in the DG group. After adjusting for age and BMI, correlations for TCa, CCa, HbA1c, HDL-C, and TG/HDL-C remained significant. The coexistence of increased BCAAs with dysglycemic status was associated with markedly higher concentrations of TCa, CCa, HbA1c, and TG, which were not observed in the DG women with low level of BCAAs. Multiple regression showed that TCa or CCa, age and BCAAs were significantly associated with HbA1c independently of BMI only in the DG group. We conclude that dysglycemia in particular predisposes women to a significant relationship between total BCAAs and circulating calcium and HbA1c, and that these relationships are independent of BMI and may reflect the pathophysiological calcium-dependent mechanisms connecting BCAAs with metabolic disturbances.

Dietary intake of branched-chain amino acids in relation to depression, anxiety and psychological distress

BackgroundThere is no previous study that examined the association between branched-chain amino acids (BCAAs) intake and odds of psychological disorders. The aim of this study was to investigate the association between dietary BCAAs and odds of psychological disorders including depression, anxiety, and psychological distress in a large sample of Iranian adults.MethodsIn this cross-sectional study on 3175 Iranian adults aged 18–55 years, a validated food frequency questionnaire was used to assess dietary intakes. BCAAs intake was computed by summing up the amount of valine, leucine, and isoleucine intake from all food items in the questionnaire. Psychological health was examined through the use of Iranian validated version of the Hospital Anxiety and Depression Scale (HADS). Psychological distress was assessed using General Health Questionnaire (GHQ). For depression and anxiety, scores of 8 or more on either subscale were considered as psychological disorders and scores of 0–7 were defined as “normal”. In terms of psychological distress, the score of 4 or more was defined as psychological distress.ResultsMean age of study participants was 36.2 ± 7.8 years. Overall, 26.4% (n = 837) of study subjects had depression, 11.9% (n = 378) had anxiety and 20.9% (n = 665) were affected by psychological distress. After controlling for potential confounders, participants in the highest tertile of total BCAAs intake had lower odds of depression (OR: 0.76; 95% CI: 0.60–0.96) and anxiety (OR: 0.66; 95% CI: 0.47–0.91) compared with those in the lowest tertile. Participants in the top tertile of valine intake had a lower odds of depression (OR: 0.76; 95% CI: 0.60–0.96) and anxiety (OR: 0.65; 95% CI: 0.47–0.90) compared with those in the bottom tertile. A significant inverse association was also seen between leucine intake and depression (OR: 0.77; 95% CI: 0.61–0.98) and anxiety (OR: 0.66; 95% CI: 0.47–0.91). In addition, a significant inverse association was observed between isoleucine intake and odds of depression (OR: 0.75; 95% CI: 0.59–0.95) and anxiety (OR: 0.62; 95% CI: 0.45–0.86). There was no significant association between isoleucine intake and odds of psychological distress.ConclusionEvidence indicating an inverse association between dietary intake of BCAAs and odds of depression and anxiety was found. Prospective studies are required to confirm these findings.

Producing high Fischer ratio peptides from milk protein and its application in infant formula milk powder

Milk protein is beneficial for the health of infants and is mainly derived from bovine, sheep, goat or camel milk. High Fischer ratio peptides usually comprise two to nine amino acid residues. The ratio is computed as a molar ratio between branched-chain amino acids (BCAAs) over aromatic amino acids (AAAs) with various claimed health-promoting functions. In this Lilliput review, the classification and nutritional functions of milk proteins are discussed, the physiological functions and preparation methods of high Fischer ratio peptides are introduced, and the application of oligopeptide with unique amino acid composition and physiological functions in infant formula milk powder are reviewed. The development status of relevant industry is also summarized with future prospects. It is concluded that application of high Fischer ratio peptides prepared from milk protein in infant formula food is of great significance and requires further studies.

Association of Circulating Branched-Chain Amino Acids with Gestational Diabetes Mellitus: A Meta-Analysis.

ContextRecently, the relationship between branched-chain amino acids (BCAAs) and diabetes mellitus (DM) has attracted worldwide attention. However, the results related to plasma BCAAs concentrations and gestational diabetes mellitus (GDM) lack statistical power due to the small sample size of a single article.ObjectivesThis study quantitatively summarized current observational studies to evaluate the association between plasma BCAAs concentration levels and GDM.MethodsA systematic search was performed to select eligible publications using PubMed and EMBASE databases until July 23, 2018. The references of relevant articles were also manually searched. The quality evaluation of included studies was according to the guidelines of the Newcastle-Ottawa Scale (NOS). Data were analyzed with Review Manager 5.3 and STATA 14.0 software. In total, seven articles (including eight studies) involving 432 subjects were included.ResultsThe results showed that all three-individual plasma BCAAs concentration levels in the GDM group were higher than those in the control group (leucine: SMD = 3.76, 95% CI: 1.70 - 5.82, P (SMD) < 0.001; isoleucine: SMD = 3.15, 95% CI: 1.42 - 4.87, P (SMD) < 0.001; valine: SMD = 2.77, 95% CI: 1.21 - 4.32, P (SMD) = 0.001), and the differences were statistically significant. In addition, subgroup analysis indicated that age, body mass index (BMI), publication year, and ethnicity were positively associated with plasma BCAAs concentrations in GDM.ConclusionsPlasma BCAAs, as potential biomarkers, might be associated with GDM risk, which provides useful information for the prevention and early diagnosis of GDM.

Branched chain amino acids are associated with the heterogeneity of the area of lipid droplets in hepatocytes of patients with non-alcoholic fatty liver disease.

Macrovesicular steatosis around the central vein (zone 3) is one of the pathological features of non-alcoholic fatty liver disease or steatohepatitis (NAFLD/NASH). The aim of this study is to elucidate precisely the association between the area of lipid droplets (LDs) and the plasma metabolic parameters in patients with NAFLD/NASH. Eighty patients with NAFLD/NASH diagnosed by needle biopsy were enrolled. The LDs around zone 3 were counted automatically by image processing software, the total area of LDs (TLDs), the maximum area of LDs (MAXLDs), the average area of LDs (AVELDs) and the heterogeneity by the coefficient of variation (CV [%]) were quantified. The correlations between these values and plasma metabolic parameters were analyzed. We evaluated the association between branched chain amino acids (BCAAs) and the heterogeneity of LDs in hepatocytes in vitro and in vivo. The MAXLDs was significantly correlated with more metabolic parameters than AVELDs and TLDs. The level of BCAAs was independently associated with the CV among the metabolic parameters. In early stage NAFLD, aspartate and alanine aminotransferase were significantly higher in the high CV group than in the low CV group. The high concentration of BCAAs increased the CV of LDs in hepatocytes accompanied by the expression of phosphor-p70 S6 kinase and sterol regulatory element-binding protein 1 in vitro. A high BCAA diet induced high heterogeneity of LDs around zone 3 in ob/ob mice. The levels of BCAAs were associated with the LD heterogeneity of hepatocytes around zone 3 in patients with NAFLD/NASH.

Integration of BCAA and Lipid Metabolism by the BCKDH Kinase and Phosphatase

Strong associations exist between branched chain amino acids (BCAA) and dysregulated glucose and lipid metabolism, but underlying mechanisms are not well understood. One factor contributing to elevated BCAA in obesity is inhibitory phosphorylation of the branched chain keto-acid dehydrogenase complex (BCKDH) in liver. We studied the impact of modulating the activity of the BCKDH kinase (BDK) and phosphatase (PPM1K) on amino acid, glucose and lipid metabolism in Zucker fatty rats (ZFR). Daily administration of a selective inhibitor of BDK, BT2 (20mg.kg-1, IP), for one week or expression of a recombinant adenovirus overexpressing PPM1K significantly lowered BCAA and branched chain keto acid (BCKA) levels in ZFR. Remarkably, these effects were accompanied by strong lowering of liver triacylglycerides and improved glucose tolerance in the absence of weight loss. Proteomics analysis of liver samples from these studies revealed that both inhibition of BDK with BT2 and adenoviral mediated overexpression of PPM1K results in reduced phosphorylation of the lipogenic enzyme ATP-citrate lyase (ACL) on its regulatory serine 454. Phosphorylation of ACL on this site is activating. Sequence analysis revealed the presence of a canonical BDK phosphorylation motif surrounding ser454 in ACL and incubation of ACL with purified BDK resulted in ACL phosphorylation in vitro. Furthermore, adenovirus-mediated overexpression of BDK increased ACL phosphorylation and activated de novo lipogenesis in liver of lean Wistar rats. Together these studies reveal a novel regulatory function for BDK and PPM1K in integration of BCAA and lipid metabolism. Moreover, we show that modulation of this node provides broad protection against metabolic abnormalities associated with obesity. Disclosure P.J. White: None. R.W. McGarrah: None. P.A. Grimsrud: None. W. Yang: None. G. Zhang: None. J.M. Haldeman: None. M. Arlotto: None. O. Ilkayeva: None. R.M. Wynn: None. D.T. Chuang: None. C.B. Newgard: Advisory Panel; Self; Eli Lilly and Company. Research Support; Self; Eli Lilly and Company.

Leucine Supplementation Differently Modulates Branched-Chain Amino Acid Catabolism, Mitochondrial Function and Metabolic Profiles at the Different Stage of Insulin Resistance in Rats on High-Fat Diet.

The available findings concerning the association between branched-chain amino acids (BCAAs)—particularly leucine—and insulin resistance are conflicting. BCAAs have been proposed to elicit different or even opposite effects, depending on the prevalence of catabolic and anabolic states. We tested the hypothesis that leucine supplementation may exert different effects at different stages of insulin resistance, to provide mechanistic insights into the role of leucine in the progression of insulin resistance. Male Sprague-Dawley rats were fed a normal chow diet, high-fat diet (HFD), HFD supplemented with 1.5% leucine, or HFD with a 20% calorie restriction for 24 or 32 weeks. Leucine supplementation led to abnormal catabolism of BCAA and the incompletely oxidized lipid species that contributed to mitochondrial dysfunction in skeletal muscle in HFD-fed rats in the early stage of insulin resistance (24 weeks). However, leucine supplementation induced no remarkable alternations in BCAA catabolism, but did enhance mitochondrial biogenesis with a concomitant improvement in lipid oxidation and mitochondrial function during the hyperglycaemia stage (32 weeks). These findings suggest that leucine trigger different effects on metabolic signatures at different stages of insulin resistance, and the overall metabolic status of the organisms should be carefully considered to potentiate the benefits of leucine.

Lowering the dietary protein levels by the use of synthetic amino acids and the use of a mono component protease

Responses of broilers to dietary amino acids (AA) have been extensively studied especially after their synthetic and crystalline forms became available. Synthetic (DL-Met and Met analogue) as well as crystalline (l-Lys and l-Thr) AA are now widely used in commercial production diets to reduce crude protein (CP) levels to allow competitive bird performance. In parallel, birds diets formulated without excess CP have reduced nitrogen excretion as well as lower costs. Diet composition affects the order of limiting AA after Thr and this has led to some debate on the feasibility of including the next limiting AA, which would be the fourth, in most of the scenarios. Using maize-soy type diets, the literature suggests that Val is the fourth AA limiting. As the commercial cost of l-Val is progressively reduced, concerns have been raised on the effectiveness of its supplementation to produce broiler responses that are similar compared with feed that does not contain this AA. Antagonisms between branched-chain amino acids (BCAA) have been reported in the past; however, their use in the current maize-soy diet commercial setting is unlikely. Formulation of diets with crystalline l-Val can potentially modify the ratio between BCAA as it is supplemented in diets that are further reduced in CP. Increased availability of AA can also be achieved when diets are supplemented with exogenous proteases; however, the resulting impact in the total profile of AA is different because a wider group of AA becomes simultaneously available when compared to diets receiving addition of synthetic/crystalline AA one by one. A scenario of CP reduction in diets seems clear with the increasing use of supplemental AA along with protease in broiler diets. The knowledge of CP reduction strategies, such as protease and synthetic AA supplementation, can be a valuable asset due to the competitive nature of broiler meat production business.

Relationship between Branched-Chain Amino Acids, Metabolic Syndrome, and Cardiovascular Risk Profile in a Chinese Population: A Cross-Sectional Study

Objective. This study aimed to evaluate the relationship between branched-chain amino acids (BCAAs), metabolic syndrome (MS), and other cardiovascular (CV) risk factors in middle-aged and elderly Chinese population at high risk for the development of cardiovascular disease (CVD). Methods. 1302 subjects were enrolled from the Huai'an Diabetes Prevention Program. Results. BCAAs levels were positively correlated with MS, its components, and CV risk profile. The odds ratio (OR) for MS among subjects in the fourth quartile of BCAAs levels showed a 2.17-fold increase compared with those in the first quartile. BCAAs were independently associated with high Framingham risk score even after adjusting for MS and its components (P < 0.0001). Additionally, the OR for high CV risk was 3.20-fold (P < 0.0001) in participants in the fourth BCAAs quartile with MS compared with participants in the first BCAAs quartile without MS. Conclusions. Increased BCAAs levels are independent risk factors of MS and CVD in addition to the traditional factors in middle-aged and elderly Chinese population. The development of CVD in MS patients with high level BCAAs is accelerated. Intervention studies are needed to investigate whether the strategy of BCAAs reduction has impacts on endpoints in patients with higher CV risk. This study is registered with ChiCTR-TRC-14005029.

The Relationships between Branched Chain Amino Acids(BCAA) and TC/HDL ratio in Female Ballet Dancers

The Relationships between Branched Chain Amino Acids(BCAA) and TC/HDL ratio in Female Ballet Dancers

The relationship between BMI and metabolomic profiles: a focus on amino acids

The role of metabolomics in the field of nutrition is continuing to grow and it has the potential to assist in the understanding of metabolic regulation and explain how minor perturbations can have a multitude of biochemical endpoints. It is this development, which creates the potential to provide the knowledge necessary to facilitate a more targeted approach to nutrition. In recent years, there has been interest in applying metabolomics to examine alterations in the metabolic profile according to weight gain/obesity. Emerging from these studies is the strong evidence that alterations in the amino acid (AA) profiles are associated with obesity. Several other studies have also shown a relationship between branched-chain amino acids (BCAA), obesity and insulin resistance. The present review focuses on the proposed link between AA and in particular BCAA, obesity and insulin resistance. In conclusion, a wealth of information is accumulating to support the role of AA, and in particular of the BCAA, in obesity.

Albumin dialysis has a favorable effect on amino acid profile in hepatic encephalopathy

According to one popular theory, hepatic encephalopathy (HE) is partly caused by an imbalance in plasma amino acid levels. The Fischer's ratio between branched chain amino acids (BCAAs) and aromatic amino acids (AAAs) correlates with the degree of HE; the lower Fischer's ratio, the higher the grade of HE. Extra-corporeal liver support systems, like MARS(R)-albumin dialysis (Molecular Adsorbents Recirculating System), can improve HE. The MARS(R) system uses a hyperosmolar albumin circuit to remove both water-soluble and albumin-bound substances. Plasma levels of neuroactive amino acids were analyzed in 82 consecutive patients with life-threatening liver failure admitted to our ICU. All patients fulfilled our indications for MARS treatment and most also fulfilled the criteria for liver transplantation (LTx). In patients with acute liver failure (ALF), as compared to those with acute decompensation of chronic liver failure (AcOChr), levels of leucine and isoleucine were significantly higher before MARS(R) treatment. In all patients, before MARS(R) treatment the higher the grade of HE grade the lower was the Fischer's ratio and higher were the levels of inhibitory neuroactive amino acids. During MARS(R) treatments the Fischer's ratio increased, and the grade of HE decreased. The increase in Fischer's ratio was mainly due to the decrease in AAAs. The plasma levels of neuroactive amino acids, methionine, glutamine, glutamate, histidine and taurine decreased during MARS(R)-treatment. In this study MARS(R)-albumin dialysis had a favorable effect on the plasma amino acid profile of patients with HE.

The altered plasma amino acid pattern is responsible for the paradoxical growth hormone response to the oral glucose tolerance test in liver cirrhosis.

An increased basal growth hormone (GH) secretion and a parodoxical GH response to the oral glucose tolerance test (OGTT) have been reported in patients with liver cirrhosis. It has been suggested that the ratio between branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs) (BCAA/ AAA ratio) may determine in part the brain concentration of the AAAs, since the BCAAs compete with the AAAs for entry across the blood-brain barrier, leading to the accumulation of false neurotransmitters such as octopamine and phenylethanolamine, which are able to stimulate GH secretion (via alpha 2-adrenergic stimulation). In this study we investigated the role of amino acids, particularly the BCAA/AAA ratio, in the paradoxical response of GH to the OGTT in patients with liver cirrhosis. Twelve non-diabetic patients with biopsy-proven cirrhosis of the liver underwent an OGTT. Three of the five patients with a paradoxical response of GH to the OGTT underwent a second oral glucose administration associated with an infusion of BCAA solution from -30 min until 180 min. During the OGTT, glucose and insulin levels increased from 4.8 +/- 0.2 to 9.6 +/- 0.7 mmol/l (P < 0.001) and from 18.8 +/- 2.6 to 104.4 +/- 13.8 mU/l (P < 0.005), respectively. GH levels increased from 8.6 +/- 2.6 to 22.4 +/- 10.8 mU/l although not significantly. Five patients had a paradoxical GH response to the OGTT. A negative correlation between serum GH values and BCAA/AAA ratio in the plasma at every time point of the OGTT was found. After co-administration of glucose and BCAA in three patients the BCAA/AAAs ratio increased, abolishing the paradoxical GH secretion. Our data suggest that in liver cirrhosis the altered BCAA/AAA ratio may influence the altered basal GH secretion and the paradoxical GH response to the OGTT, probably by an increase of adrenergic mediators in the brain. Moreover, the increase of BCAA/AAA ratio seems to be able to abolish the GH paradoxical response to the OGTT.