Lower Branched-chain Amino Acids Research Articles

BCAA-producing Clostridium symbiosum promotes colorectal tumorigenesis through the modulation of host cholesterol metabolism

Identification of potential bacterial players in colorectal tumorigenesis has been a focus of intense research. Herein, we find that Clostridium symbiosum (C.symbiosum) is selectively enriched in tumor tissues of patients with colorectal cancer (CRC) and associated with higher colorectal adenoma recurrence after endoscopic polypectomy. The tumorigenic effect of C.symbiosum is observed in multiple murine models. Single-cell transcriptome profiling along with functional assays demonstrates that C.symbiosum promotes the proliferation of colonic stem cells and enhances cancer stemness. Mechanistically, C.symbiosum intensifies cellular cholesterol synthesis by producing branched-chain amino acids (BCAAs), which sequentially activates Sonic hedgehog signaling. Low dietary BCAA intake or blockade of cholesterol synthesis by statins could partially abrogate the C.symbiosum-induced cell proliferation invivo and invitro. Collectively, we reveal C.symbiosum as a bacterial driver of colorectal tumorigenesis, thus identifying a potential target in CRC prediction, prevention, and treatment.

Association of childhood food consumption and dietary pattern with cardiometabolic risk factors and metabolomics in late adolescence: prospective evidence from ‘Children of 1997’ birth cohort

BackgroundHealthy diet might protect against cardiometabolic diseases, but uncertainty exists about its definition and role in adolescence.MethodIn a subset of Hong Kong’s ‘Children of 1997’ birth cohort (n=2844 out of...

Adverse plasma branched-chain amino acid profile mirrors fatty muscle degeneration in diabetic heart failure patients.

Elevated plasma branched-chain amino acids (BCAAs) are tightly linked to incident diabetes and its complications, while lower BCAAs are associated with adverse outcomes in the elderly and heart failure (HF) patients. The interplay between body compositions and plasma BCAAs, especially under the influence of co-morbid diabetes in HF patients, is not well understood. Here, we examined the impact of diabetes on the prognostic value of plasma BCAA and its association with body compositions in HF patients. We retrospectively examined 301 HF patients (70±15years old; 59% male), among which 36% had diabetes. Blood samples for plasma BCAA measurements were collected in a fasting state after stabilization of HF and analysed using ultraperformance liquid chromatography. A dual-energy X-ray absorptiometry scan assessed regional body compositions, and muscle wasting was defined as appendicular skeletal muscle mass index (ASMI)<7.00 and <5.40kg/m2 for males and females, respectively, according to the criteria of the Asian Working Group for Sarcopenia. Although analyses of covariance revealed that plasma BCAAs were significantly higher in diabetic patients, low valine (<222.1nmol/mL) similarly predicted adverse events defined by HF hospitalization, lethal arrhythmia, or all-cause death in both diabetic and non-diabetic patients independently of age, sex, and NT-proBNP (adjusted hazard ratio [HR] 3.1, 95% confidence interval [CI] of 1.1-8.6 and adjusted HR 2.67, 95% CI 1.1-6.5, respectively; P for interaction 0.88). In multivariate linear regression analyses comprising age, sex, and regional body compositions as explanatory variables, plasma BCAAs were positively correlated with visceral adipose tissue area in non-diabetic patients (standardized β coefficients [β]=0.44, P<0.001). In contrast, in diabetic patients, plasma BCAAs were correlated positively with ASMI (β=0.49, P=0.001) and negatively with appendicular fat mass index (AFMI; β=-0.42, P=0.004). Co-morbid diabetes was independently associated with muscle wasting (adjusted odds ratio 2.1, 95% CI 1.1-4.0) and significantly higher plasma 3-methylhistidine level, a marker of myofibrillar degradation. In diabetic patients, ASMI uniquely showed a J-shaped relationship with AFMI, and in a subgroup of HF patients with muscle wasting, diabetic patients showed 12% higher AFMI than non-diabetic patients despite comparable ASMI reductions. Despite higher plasma BCAA levels in HF patients with diabetes, the prognostic value of low valine remained consistent regardless of diabetes status. However, low BCAAs were distinctly associated with fatty muscle degeneration in the extremities in diabetic patients, suggesting the importance of targeted interventions to prevent such tissue remodelling in this population.

Lactate Suppresses, While Glutamine or Branched-Chain Amino Acids Support, Cardiac Fibroblast Activation

Background: Although metabolic changes occur during activation of cardiac fibroblasts, it remains unclear how different metabolic pathways influence fibroblast phenotype and function. Substrates used for biosynthetic pathways could be particularly important to the fibrotic response because activated fibroblasts require higher anabolic output to provide biomolecular building blocks for cell division and ECM secretion. Hence, elucidating how metabolism influences fibroblast differentiation and activation could provide valuable information for understanding mechanisms of fibrosis. Hypothesis: We hypothesized that the availability of specific metabolic substrates regulate myofibroblast differentiation. Methods and Results: Naïve cardiac fibroblasts were isolated from wildtype, male C57BL/6J mice and treated with TGFβ or bFGF for 48 h. To examine metabolic genes that respond to profibrotic stimuli, we utilized RNA sequencing, which indicated that TGFβ significantly increases transcription of numerous glycolytic and glutamine metabolism genes as well as transporters for branched-chain amino acids (BCAAs), glutamine, and lactate. Guided by these results, we used an αSMA-reporter assay to examine how lactate, glutamine and BCAA availability influence TGFβ-induced myofibroblast differentiation. Fibroblasts were treated with deficient media supplemented with increasing concentrations of substrate and challenged with TGFβ for 48 hours, followed by assessment of αSMA positivity. In a dose-dependent manner, fibroblasts treated with lactate exhibited decreased αSMA reporter activity (EC50=6.17mM). Furthermore, extracellular flux analysis revealed that the presence of lactate (1mM–10mM) significantly reduced basal oxygen consumption rate and extracellular acidification rate in TGFβ-treated cells (n=2, p&lt;0.05). In contrast, αSMA expression was blunted with diminishing concentrations of glutamine (n=3, p&lt;0.05) and BCAAs, indicating suffcient supply of these substrates is essential for fibroblast differentiation. In addition, immunoblotting data of TGFβ-treated fibroblasts revealed that low extracellular BCAA levels (0 or 100μM) decreased abundance of col1a1 and periostin compared with treatment with BCAAs within the physiological range (400μM; n=4, p&lt;0.05). Conclusion: These preliminary findings provide insight into how specific alterations of glycolysis, glutaminolysis, and BCAA metabolism modulate fibroblast activation in vitro. Additional studies that include alterations to other critical substrates (glucose, fatty acids, ketone bodies, etc.) and enzymes of ancillary biosynthetic pathways of glucose metabolism could provide additional insights into how metabolism regulates fibroblast function. Ultimately, the goal of these studies is to discover potential genetic and pharmacological interventions that positively influence wound healing in the infarcted heart and limit the burden of cardiac fibrosis. NIH and AHA. This is the full abstract presented at the American Physiology Summit 2024 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.

Abstract 14967: Branching Out: Disrupted Branched Chain Amino Acid Metabolism Exacerbates Pulmonary Arterial Hypertension

Introduction: Valine, leucine, and isoleucine are essential branched chain amino acids (BCAA), and recent epidemiological studies report elevated BCAAs predict worse outcomes in several cardiovascular diseases with metabolic origins such as diabetes, heart failure, and hypertension. However, the role of BCAA metabolism in pulmonary arterial hypertension pathophysiology is relatively unexplored. Hypothesis: BCAAs are elevated in human PAH and reduction of BCAAs via small molecule activation of BCAA catabolism and dietary interventions combats PAH severity in preclinical PAH. Methods: Literature search of human PAH metabolomics studies was conducted. For rodent studies, male Sprague Dawley rats were divided into three groups: control (saline injection), monocrotaline (MCT) vehicle (MCT-V), or MCT-BT2, a small molecule inducer of BCAA catabolism. BT2 was administered at 20mg/kg/day. A low BCAA dietary intervention was implemented, with male Sprague Dawley rats divided into two groups: MCT-standard chow diet and MCT-low BCAA diet. To assess exercise capacity, rodents underwent a maximal exercise testing protocol before echocardiographic and hemodynamic assessments of PAH. Proteomic analysis of lung mitochondrial extracts was performed to define the molecular effects of BT2. Results: Of 11 studies evaluating human PAH metabolomics, 7 studies reported elevated BCAAs or BCAA metabolites in PAH. BT2 treatment improved exercise performance, reduced PA pressures, and augmented RV function. Moreover, the MCT-BT2 group possessed a distinct lung proteomic signature with changes in inflammatory and metabolic pathways. Finally, the low BCAA diet intervention modestly combatted PAH severity. Conclusions: BCAA metabolism is disrupted in human PAH and interventions that reduce circulating BCAAs display therapeutic potential in rodent PAH.

Use of Branched-Chain Amino Acids as a Potential Treatment for Improving Nutrition-Related Outcomes in Advanced Chronic Liver Disease.

Advanced chronic liver disease (ACLD) represents a complex and multifactorial clinical entity characterized by liver dysfunction and associated complications. In recent years, the significance of nutritional status in ACLD prognosis has gained considerable attention. This review article delves into the multifactorial pathogenesis of malnutrition in ACLD and its profound consequences for health outcomes. We explore the clinical implications of secondary sarcopenia in ACLD and highlight the critical relevance of frailty in both decompensated and compensated ACLD. A specific focus of this review revolves around branched-chain amino acids (BCAAs) and their pivotal role in managing liver disease. We dissect the intricate relationship between low Fischer's ratio and BCAA metabolism in ACLD, shedding light on the molecular mechanisms involved. Furthermore, we critically evaluate the existing evidence regarding the effects of BCAA supplementation on outcomes in ACLD patients, examining their potential to ameliorate the nutritional deficiencies and associated complications in this population.

Fasting and non-fasting plasma levels of monomethyl branched chain fatty acids: Implications for maple syrup urine disease.

The branched-chain amino acids (BCAA) leucine, valine, and isoleucine provide precursors for monomethyl branched-chain fatty acids (BCFA). Established reference ranges for BCFAs are lacking. In maple syrup urine disease (MSUD), a rare inborn error of BCAA metabolism, the endogen production is impaired and MSUD patients are treated with a low protein (low BCAA) diet. The protein restriction may affect the dietary intake of BCFA, depending on the dietary choices made. Patients with MSUD are prescribed a more or less protein-restricted diet depending on the severity of the disease. The combination of a protein-restricted diet and subsequent impaired endogenous synthesis may render MSUD patients sensitive to BCFA deficiency, with yet unknown implications. To investigate the possibility of lower circulatory BCFA levels in MSUD that favors dietary BCFA supplementation, we first established fasting-state reference ranges for selected BCFAs and saturated/unsaturated fatty acids in plasma. Then, the effect of fasting on BCFA levels was evaluated by comparing the distribution in a fasting versus a non-fasting cohort. To test the hypothesis that BCFA deficiency could contribute to MSUD pathophysiology, we recruited patients with intermittent, intermediate, and classical form of MSUD and analyzed the corresponding BCFA z-scores. None of the BCFA species had |z-scores| > 2 relative to the reference range. Our findings do not support the requirement of BCFA supplementation in MSUD patients. The origin of BCFAs is discussed. Impaired capacity to synthesize BCFA do not manifest as reduced plasma levels in MSUD, suggesting that endogenous synthesis is dispensable for plasma levels.

Melatonin improves behavioral parameters and oxidative stress in zebrafish submitted to a leucine-induced MSUD protocol.

Maple syrup urine disease (MSUD) is an inherited metabolic disorder caused by a deficiency in branched-chain alpha-ketoacid dehydrogenase complex (BCKAC). The treatment is a standard therapy based on a protein-restricted diet with low branched-chain amino acids (BCAA) content to reduce plasma levels and, consequently, the effects of accumulating their metabolites, mainly in the central nervous system. Although the benefits of dietary therapy for MSUD are undeniable, natural protein restriction may increase the risk of nutritional deficiencies, resulting in a low total antioxidant status that can predispose and contribute to oxidative stress. As MSUD is related to redox and energy imbalance, melatonin can be an important adjuvant treatment. Melatonin directly scavenges the hydroxy radical, peroxyl radical, nitrite anion, and singlet oxygen and indirectly induces antioxidant enzyme production. Therefore, this study assesses the role of melatonin treatment on oxidative stress in brain tissue and behavior parameters of zebrafish (Danio rerio) exposed to two concentrations of leucine-induced MSUD: leucine 2 mM and 5mM; and treated with 100 nM of melatonin. Oxidative stress was assessed through oxidative damage (TBARS, DCF, and sulfhydryl content) and antioxidant enzyme activity (SOD and CAT). Melatonin treatment improved redox imbalance with reduced TBARS levels, increased SOD activity, and normalized CAT activity to baseline. Behavior was analyzed with novel object recognition test. Animals exposed to leucine improved object recognition due to melatonin treatment. With the above, we can suggest that melatonin supplementation can protect neurologic oxidative stress, protecting leucine-induced behavior alterations such as memory impairment.

Short-Term Decreasing and Increasing Dietary BCAA Have Similar, but Not Identical Effects on Lipid and Glucose Metabolism in Lean Mice.

Branched-chain amino acids (BCAA) showed multiple functions in glycolipid metabolism and protein synthesis. However, the impacts on the metabolic health of low or high dietary BCAA remain controversial due to the various experimental conditions. Gradient levels of BCAA were supplemented in lean mice for four weeks: 0BCAA (without BCAA), 1/2BCAA (half BCAA), 1BCAA (regular BCAA), and 2BCAA (double BCAA). The results showed that the diet without BCAA caused energy metabolic disorders, immune defects, weight loss, hyperinsulinemia, and hyperleptinemia. 1/2BCAA and 2BCAA diets reduced body fat percentage, but 1/2 BCAA also decreased muscle mass. 1/2BCAA and 2BCAA groups improved lipid and glucose metabolism by affecting metabolic genes. Meanwhile, significant differences between low and high dietary BCAA were observed. The results of this study provide evidence and reference for the controversy about dietary BCAA levels, which indicates that the main difference between low and high BCAA dietary levels may present in the longer term.

Nut consumption is associated with a shift of the NMR lipoprotein subfraction profile to a less atherogenic pattern among older individuals at high CVD risk

BackgroundScientific evidence has accumulated on the beneficial effects of nut consumption on cardiovascular risk and cholesterol reduction, but few studies have examined the effects of nuts on advanced measures of lipoprotein atherogenicity determined by nuclear magnetic resonance (NMR) spectroscopy. We analyzed associations between the amount and type of of nuts consumed and advanced measures of lipoprotein atherogenity and insulin resistance in older individuals at high cardiovascular risk.MethodsThe present observational study was carried out within the framework of the Prevención con Dieta Mediterránea (PREDIMED) trial. Cross-sectional and longitudinal analyses after 1-year of follow-up were conducted in 196 men and women recruited in the PREDIMED-Reus (Spain) center. Dietary intake was assessed using a validated semi-quantitative food questionnaire. Baseline and 1-year fasting plasma lipoprotein and metabolite profiling were performed in plasma using NMR spectra Vantera® Clinical Analyzer. Associations by tertiles of nut consumption between baseline and 1-year changes and advanced measures of lipoprotein atherogenicity, branched chain amminoacids, and measures of insulin resistance were tested by multivariable-adjusted ANCOVA models.ResultsCompared to paticipants in the bottom tertile, those in the top tertile of total nut consumption showed higher levels of large HDL particles and HDL-cholesterol, lower levels of branched-chain amino acids (BCAA) and GlycA, and reduced lipoprotein insulin resistance and diabetes risk index. Participants in the top tertile of walnut consumption disclosed lower levels of very large VLDL, total LDL particles, LDL-cholesterol, and GlycA. Participants in the top tertile of non-walnut nut consumption displayed higher levels of total HDL particles, HDL-cholesterol and apoliporotein A1, lower BCAA and GlycA, and reduced lipoprotein insulin resistance. Participants in the top tertile of 1-year changes in walnut consumption showed increases in medium-sized HDL particles in comparison to the bottom tertile.ConclusionsIn older individuals at high cardiovascular risk, increasing nut consumption was associated with a shift of the NMR lipoprotein subfraction profile to a less atherogenic pattern, as well as lower circulating concentrations of BCAA and decreased insulin resistance. These results provide novel mechanistic insight into the cardiovascular benefit of nut consumption.Trial registration ISRCTN35739639; registration date: 05/10/2005; recruitment start date 01/10/2003.

Longitudinal Branched-Chain Amino Acids, Lifestyle Intervention, and Type 2 Diabetes in the Finnish Diabetes Prevention Study.

ContextCirculating branched-chain amino acids (BCAAs) are associated with the risk of type 2 diabetes (T2D).ObjectiveWe examined to what extent lifestyle intervention aiming to prevent T2D interacts with this association and how BCAA concentrations change during the intervention.MethodsWe computed trajectory clusters by k-means clustering of serum fasting BCAAs analyzed annually by mass spectrometry during a 4-year intervention. We investigated whether baseline BCAAs, BCAA trajectories, and BCAA change trajectories predicted T2D and whether BCAAs predicted T2D differently in the intervention (n = 198) and control group (n = 196).ResultsElevated baseline BCAAs predicted the incidence of T2D in the control group (hazard ratio [HR] 1.05 per 10 μmol/L, P = 0.01), but not in the intervention group. BCAA concentration decreased during the first year in the whole cohort (mean −14.9 μmol/L, P < 0.001), with no significant difference between the groups. We identified 5 BCAA trajectory clusters and 5 trajectory clusters for the change in BCAAs. Trajectories with high mean BCAA levels were associated with an increased HR for T2D compared with the trajectory with low BCAA levels (trajectory with highest vs lowest BCAA, HR 4.0; P = 0.01). A trajectory with increasing BCAA levels had a higher HR for T2D compared with decreasing trajectory in the intervention group only (HR 25.4, P < 0.001).ConclusionLifestyle intervention modified the association of the baseline BCAA concentration and BCAA trajectories with the incidence of T2D. Our study adds to the accumulating evidence on the mechanisms behind the effect of lifestyle changes on the risk of T2D.

Elevated BCAA Suppresses the Development and Metastasis of Breast Cancer.

Branched-chain amino acids (BCAAs) are the three essential amino acids including leucine, isoleucine, and valine. BCAA metabolism has been linked with the development of a variety of tumors. However, the impact of dietary BCAA intake on breast tumor progression and metastasis remains to be fully explored. Here, we unexpectedly find that the elevated BCAA, either in the genetic model or via increasing dietary intake in mice, suppresses the tumor growth and lung metastasis of breast cancer. The survival analysis shows that BCAA catabolic gene expression is strongly associated with long-term oncological outcomes in patients with breast cancer. In Pp2cm knockout mice in which BCAAs accumulate due to the genetic defect of BCAA catabolism, the breast tumor growth is suppressed. Interestingly, while the cell proliferation and tumor vasculature remain unaffected, more cell death occurs in the tumor in Pp2cm knockout mice, accompanied with increased natural killer (NK) cells. Importantly, increasing BCAA dietary intake suppresses breast tumor growth in mice. On the other hand, there are fewer lung metastases from primary breast tumor in Pp2cm knockout mice and the high BCAA diet-fed mice, suggesting high BCAA also suppresses the lung metastasis of breast cancer. Furthermore, low BCAA diet promotes lung colonization of breast cancer cells in tail vein model. The migration and invasion abilities of breast cancer cells are impaired by high concentration of BCAA in culture medium. The suppressed tumor metastasis and cell migration/invasion abilities by elevated BCAA are accompanied with reduced N-cadherin expression. Together, these data show high BCAA suppresses both tumor growth and metastasis of breast cancer, demonstrating the potential benefits of increasing BCAA dietary intake in the treatment of breast cancer.

Dietary Strawberries Lower Branched Chain Amino Acids in Adults With the Metabolic Syndrome in Targeted Serum Metabolomics Analyses

ObjectivesDietary berries have been shown to lower cardio-metabolic risks in clinical trials. We examined the dose-response effects of two dietary achievable doses of strawberries on serum metabolomics related to energy metabolism in adults with metabolic syndrome. MethodsIn this 14-week randomized controlled crossover study adults with metabolic syndrome were assigned to one of the three arms for 4 weeks separated by a one-week washout period: control powder, one serving strawberries (13 g powder/day), and 2.5 servings strawberries (32 g powder/day). The freeze-dried powders were blended in water and participants consumed half the daily dose in the morning and half in the evening. Participants were instructed to follow their usual diet and lifestyle while refraining from consuming other berries and related products throughout the study. Metabolic profiling was performed using a high-throughput serum nuclear magnetic resonance (NMR) metabolomics platform (West Coast Metabolomics Center, UC Davis, USA). ResultsThirty-three participants completed all three phases of the trial (baseline profiles: weight: 90.8 ± 22.4 kg, BMI: 33.1 ± 4.2 kg/m2, waist circumference: 109 ± 12.5 cm, HbA1c:5.8 ± 0.2%). Outcome measures were analyzed using a multivariate analysis of variance with statistical significance set at p < 0.05. Among the targeted primary metabolites, strawberry supplementation at a dose of 2.5 servings per day for 4 weeks significantly decreased the circulating concentrations of branched chain amino acids (valine and leucine) as targeted primary metabolites in the study (P < 0.05). No effects were noted on isoleucine, alanine, and other metabolites of the citric acid cycle. ConclusionsThese branched chain amino acids are increased in individuals with obesity and are associated with insulin resistance or type 2 diabetes. These data suggest that consuming strawberries at two and half servings for four weeks significantly improves metabolomic profiles related to insulin resistance in adults with the metabolic syndrome. Funding SourcesCalifornia Strawberry Commission and NIH COBRE.

348-OR: Glycine and Branched-Chain Amino Acids (BCAA) Metabolic Signature in Youth with Obesity and Type 2 Diabetes (T2D)

BCAAs are associated with increased risk for T2D in adults, while glycine (Gly) appears to be have an inverse relationship. β-cell function is central to the development of T2D in youth. The relationship of Gly and BCAA to β-cell function in youth is not clear. We investigated the relationship between Gly vs. the BCAA: Leucine (Leu) , Isoleucine (Ile) and Valine (Val) , to insulin sensitivity (IS) and β-cell function in youth across the spectrum of glycemia. Adolescents (65 female/62 male; 15.5±1.9 y.o.; 30 with normal weight normal glucose tolerance (NW-NGT) , 33 obese-NGT, 34 prediabetes, and 30 T2D) underwent assessment of AA concentrations (mass spectrometry) , fasting and at steady state (SS) of a 3-hr hyperinsulinemic-euglycemic clamp (in-vivo IS) ; insulin secretion by 2-hr hyperglycemic clamp; adipokines, body composition (DXA) and visceral fat (MRI) . The disposition index (DI) (measure of β-cell function) = first phase insulin x IS per fat free mass (DIFFM) . We performed analysis of variance (adjusting for sex, race-ethnicity and Tanner stage) and correlation analyses. Fasting and SS-Gly were lower and SS-BCAA higher in the groups with obesity compared with NW with post-hoc significant differences in T2D vs. NW (p&amp;lt;0.0for fasting and SS-Gly, SS-Ile, and p=0.02 for SS-Val) and in prediabetes vs. NW (for Gly, Val and Ile) . Fasting and SS-Gly negatively and SS-BCAA positively associated with %body fat, waist/hip, and visceral fat, while Gly positively and BCAA negatively related to adiponectin. Fasting and SS-Gly (r=0.4, p&amp;lt;0.001) positively and SS-BCAA (r=-0.4 for Val, Leu, Ile, p&amp;lt;0.001) negatively related to ISFFM. Gly positively (r=0.27, p=0.005) , SS-Ile (r=-0.26, p=0.006) inversely related to DIFFM. Gly is positively related to IS and β-cell function and negatively to adiposity measures, with opposite relationships observed for BCAA. A metabolic signature of low Gly and elevated BCAA may constitute a biomarker to identify youth at risk for β-cell failure. Disclosure H.El ayash: None. M.A.Mohammad: None. R.S.Shawar: None. R.S.Kanchi: None. S.Sharma: None. M.R.Puyau: None. C.Coarfa: None. F.Bacha: Other Relationship; AstraZeneca, Takeda Pharmaceutical Company Limited, Research Support; National Institute of Diabetes and Digestive and Kidney Diseases, U.S. Department of Agriculture. Funding USDA-ARS

Low Branched Chain Amino Acids and Tyrosine in Thai Patients with Type 2 Diabetes Mellitus Treated with Metformin and Metformin-Sulfonylurea Combination Therapies.

Type 2 diabetes mellitus (T2DM) is a growing public health challenge for Thailand (current prevalence ~10.0%). Amino acids offer novel biomarkers to predict risk of T2DM and indicate sub-optimal disease management, which could facilitate earlier treatment. We studied amino acid profiles in a Thai cohort comprising of individuals with T2DM (n = 65 single-drug-treated; n = 38 multi-drug-treated) compared to healthy controls (n = 104) using liquid chromatography-mass spectrometry. Age and BMI were significantly lower in the healthy controls compared to the single or multi-treated T2DM groups. The BCAA (leucine and valine) were significantly lower in the single and multi-treated T2DM groups compared to healthy controls (p < 0.001 and p < 0.001) and isoleucine was significantly lower in the single-treated compared to the healthy controls (p = 0.014). These findings beg the question whether BCAAs supplementation be beneficial in T2DM patients treated with single or multi-drug therapy? Tyrosine was significantly lower in the single and multi-treated T2DM groups compared to healthy controls (p < 0.001 and p = 0.002), whereas phenylalanine was significantly higher in the multi-treated T2DM group compared to the single treated T2DM group (p = 0.045). We provide novel insights into the effects of diabetes treatments on these amino acids in insulin resistant states such as T2DM in a unique but understudied Thai population.

Does branched-chain amino acid supplementation improve pulmonary rehabilitation effect in COPD?

BackgroundMuscle wasting is frequent in chronic obstructive lung disease (COPD) and associated with low branched-chain amino acids (BCAA). We hypothesized that BCAA supplementation could potentiate the effect of a pulmonary rehabilitation program (PRP) by inducing muscular change. Materials and methodsSixty COPD patients (GOLD 2–3) were involved in an ambulatory 4-week PRP either with BCAA oral daily supplementation or placebo daily supplementation in a randomized double-blind design. Maximal exercise test including quadriceps oxygenation measurements, functional exercise test, muscle strength, lung function tests, body composition, dyspnea and quality of life were assessed before and after PRP. ResultsFifty-four patients (64.9 ± 8.3 years) completed the protocol. In both groups, maximal exercise capacity, functional and muscle performances, quality of life and dyspnea were improved after 4-week PRP (p ≤ 0.01). Changes in muscle oxygenation during the maximal exercise and recovery period were not modified after 4-week PRP in BCAA group. Contrarily, in the placebo group the muscle oxygenation kinetic of recovery was slowed down after PRP. ConclusionThis study demonstrated that a 4-week PRP with BCAA supplementation is not more beneficial than PRP alone for patients. A longer duration of supplementation or a more precise targeting of patients would need to be investigated to validate an effect on muscle recovery and to demonstrate other beneficial effects.

Changes of Plasma Amino Acid Profiles in Infants With a Nutrient-Fortified Complementary Food Supplement: Evidence From a 12-Month Single-Blind Cluster-Randomized Controlled Trial.

Stunting is reportedly associated with low circulating levels of essential amino acids (EAAs). This study examined the effect of a macronutrient- and micronutrient-fortified complementary food supplement (KOKO Plus) on specific plasma EAA levels and stunting in infants aged 6–18 months. In a single-blind cluster-randomized controlled trial conducted in Ghana, infants were enrolled at 6 months and followed until 18 months. Thirty-eight communities were randomly assigned to receive KOKO Plus (KP, fourteen communities, n = 321), multiple-micronutrient powder (MN, thirteen communities, n = 327), or only nutritional education as control group (NE, eleven communities, n = 318), and all groups received nutrition education. Plasma amino acids (AAs) were measured at 6, 12, and 18 months (end point). Mixed-effects models were used to assess the effect of the intervention on plasma AAs, and the relationship between plasma branched-chain AAs (BCAAs) and the risk of stunting was assessed. At the end point, total BCAA concentrations (±standard error) significantly exceeded baseline in the KP (284.2 ± 4.3 μM) and NE (289.1 ± 4.4 μM) groups but not the MN group (264.4 ± 4.1 μM). After adjustment for compliance at 200 sachets, plasma BCAAs exceeded in the KP group (284.5 ± 4.2 μM) compared to the MN group (264.6 ± 4 μM). Plasma BCAAs were positively correlated with changes in length-for-age Z-score from baseline (R = 0.327, p = 0.048). In conclusion, the plasma BCAA concentrations of infants that received KP and the NE group was significantly higher compared to the MN group but there were no differences between the KP and NE group at end point. Improved plasma BCAAs may be due to improved nutrient intake by infants exposed to KP or NE. Low BCAAs were associated with stunting, replicating the previous finding.Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT03181178?term=NCT03181178&draw=2&rank=1, identifier: NCT03181178.

Clinical utility of low branched-chain amino acid modular diets in patients with isovaleric aciduria and maple syrup urine disease

Introduction: Modular diets (MDs) with low amount of offending amino acids have been developed using locally available food ingredients as alternatives to commercial formulas for the treatment of branched-chain organic acidurias (BCOAs). Herein, we conducted a clinical investigation of MDs in patients with BCOAs. Methods: Modular diet A (MDA), with low leucine was produced for maple syrup urine disease (MSUD), and modular diet B (MDB) products, MDB-1, -2, -3, and -4, with low leucine, valine, methionine and threonine were made for isovaleric aciduria (IVA)/methylmalonic aciduria (MMA)/propionic aciduria (PA). Children aged 4-18 years, with MSUD, IVA, PA or MMA were invited to participate in the study. The research subjects switched from metabolic formula protocol to modular diet protocol. They were followed-up at 0, 1, 2, 4, and 6 months. Clinical efficacies of MDs were determined by completion of study, compliance to MDs, clinical outcomes and complications, and parental satisfaction. Results: Six children (2 MSUD and 4 IVA) participated and completed the study. Compliance to MDA was 100% in MSUD subjects with G-tube feeding, while compliance to MDB varied among self-fed individuals with IVA. One subject with MSUD was clinically stable throughout the study, while the other experienced metabolic instability. All IVA individuals showed clinical and laboratory stability during the study. One MSUD and three IVA families preferred the metabolic formula, whereas the other IVA family reported no preference and the other MSUD subject preferred MDs. Conclusion: We provided a proof of concept in developing modular diets for BCOAs, and showed favourable outcomes when using MDs in IVA and varying clinical benefits in MSUD.

202-OR: Cell-Autonomous Impairment of BCAA Catabolism in White Adipocytes Leads to Systemic Metabolic Dysregulation

Increased levels of serum branched-chain amino acids (BCAA) is associated with obesity, insulin resistance (IR), and type 2 diabetes (T2D). However, the mechanisms that trigger perturbations in BCAA homeostasis, and whether elevated BCAA causes obesity and other metabolic impairments or is a consequence of them is not clear. Young knock-in mice bearing the human T2D-linked R1788W variant in the cytoskeletal protein ankyrin-B (AnkB) show normal body weight and composition. These mice display increased glucose uptake by white adipose tissue (WAT) due to deficient internalization of the glucose transporter GLUT4. We reported that sustained elevation in glucose disposal in WAT leads to the onset of increased adiposity, lipotoxicity, systemic inflammation, and IR in AnkB mutant mice with age or in young animals fed Western diets. Non-obese R1788W AnkB mice also exhibit transcriptional changes consistent with lower BCAA catabolism in WAT. Here, we show that AnkB deficits impair BCAA catabolism in WAT prior to the onset of obesity. Lean R1788W AnkB mice show reduction in surface levels of the BCAA transporter Asct2 and BCAA uptake together with downregulation of BCAA catabolic enzymes in WAT. These deficits are concomitant with elevations in serum levels of BCAA and related acylcarnitines. Reduced expression of BCAA catabolic enzymes was also observed in WAT of lean WAT-specific AnkB KO mice. In contrast, AnkB deficiency did not alter BCAA oxidation in skeletal muscle (SKM), brown adipose tissue, or liver. Studies in control and R1788W AnkB mice fed isocaloric low and high fat (HFD) diets enriched in BCAA suggest that BCAA elevation triggers mitochondrial dysfunction, impairments in insulin secretion by the pancreas and in insulin signaling in SKM. Our data indicates that elevated circulating BCAA impair glucose tolerance and insulin sensitivity independently of obesity, and that these deleterious effects are potentiated by HFD. Disclosure J. Tzeng: None. A. Aguillard: None. D. Lorenzo: None. Funding American Diabetes Association (1-19-JDF-081 to D.L.)

Easy clinical predictor for low BCAA to tyrosine ratio in chronic liver disease patients with hepatocellular carcinoma: Usefulness of ALBI score as nutritional prognostic marker.

Background/AimLow branched‐chain amino acid (BCAA) to tyrosine ratio (BTR) is known as an indicator of amino acid imbalance. We elucidated usefulness of newly developed albumin–bilirubin (ALBI) score as alternative methods of BTR in patients with naïve hepatocellular carcinoma (HCC) retrospectively.Materials/MethodsIn 842 patients with HCC and without BCAA supplementation (71 years, male 614, Child‐Pugh A:B:C = 689:116:37), relationships among BTR and clinical features were evaluated. Of those, 438 patients, with Milan criteria HCC, treated curatively were divided into the high‐BTR (>4.4) (n = 293) and low‐BTR (≤4.4) (n = 145) groups. The prognostic value of BTR was evaluated using inverse probability weighting (IPW) with propensity score.ResultsThe low‐BTR group showed worse prognosis than the other (3‐, 5‐, 10‐year overall survival rates: 88.9% vs. 86.3%/70.5% vs. 78.1%/38.1% vs. 52.3%, respectively; p < 0.001). Multivariate Cox‐hazard analysis adjusted for IPW showed elderly (≥65 years) HR 2.314, p = 0.001), female gender (HR 0.422, p < 0.001), ECOG PS ≥2 (HR 3.032, p = 0.002), low platelet count (HR 1.757, p = 0.010), and low BTR (≤4.4) (HR 1.852, p = 0.005) to be significant prognostic factors. Both serum albumin level (r = 0.370, p < 0.001) and ALBI score (r = −0.389, p < 0.001) showed a significant relationship with BTR. Child‐Pugh class B, modified ALBI grade (mALBI) 2a, and mALBI 2b predictive values for BTR were 3.589, 4.509, and 4.155 (AUC range: 0.735–0.770), respectively, while the predictive value of ALBI score for low‐BTR (≤4.4) was −2.588 (AUC 0.790).ConclusionALBI score −2.588 was a predictor for low‐BTR (≤4.4), which was prognostic factors for early HCC patients, and at least patients with mALBI 2b might have an amino acid imbalance.