Branched-chain Amino Acids Treatment Research Articles

Head Injury Treatment With Healthy and Advanced Dietary Supplements: A Pilot Randomized Controlled Trial of the Tolerability, Safety, and Efficacy of Branched Chain Amino Acids in the Treatment of Concussion in Adolescents and Young Adults.

Concussion is a common injury in the adolescent and young adult populations. Although branched chain amino acid (BCAA) supplementation has shown improvements in neurocognitive and sleep function in pre-clinical animal models of mild-to-moderate traumatic brain injury (TBI), to date, no studies have been performed evaluating the efficacy of BCAAs in concussed adolescents and young adults. The goal of this pilot trial was to determine the efficacy, tolerability, and safety of varied doses of oral BCAA supplementation in a group of concussed adolescents and young adults. The study was conducted as a pilot, double-blind, randomized controlled trial of participants ages 11-34 presenting with concussion to outpatient clinics (sports medicine and primary care), urgent care, and emergency departments of a tertiary care pediatric children's hospital and an urban tertiary care adult hospital, between June 24, 2014 and December 5, 2020. Participants were randomized to one of five study arms (placebo and 15 g, 30 g, 45 g, and 54 g BCAA treatment daily) and followed for 21 days after enrollment. Outcome measures included daily computerized neurocognitive tests (processing speed, the a priori primary outcome; and attention, visual learning, and working memory), symptom score, physical and cognitive activity, sleep/wake alterations, treatment compliance, and adverse events. In total, 42 participants were randomized, 38 of whom provided analyzable data. We found no difference in our primary outcome of processing speed between the arms; however, there was a significant reduction in total symptom score (decrease of 4.4 points on a 0-54 scale for every 500 g of study drug consumed, p value for trend = 0.0036, [uncorrected]) and return to physical activity (increase of 0.503 points on a 0-5 scale for every 500 g of study drug consumed, p value for trend = 0.005 [uncorrected]). There were no serious adverse events. Eight of 38 participants reported a mild (not interfering with daily activity) or moderate (limitation of daily activity) adverse event; there were no differences in adverse events by arm, with only two reported mild adverse events (both gastrointestinal) in the highest (45 g and 54 g) BCAA arms. Although limited by slow enrollment, small sample size, and missing data, this study provides the first demonstration of efficacy, as well as safety and tolerability, of BCAAs in concussed adolescents and young adults; specifically, a dose-response effect in reducing concussion symptoms and a return to baseline physical activity in those treated with higher total doses of BCAAs. These findings provide important preliminary data to inform a larger trial of BCAA therapy to expedite concussion recovery.

Branched-Chain Amino Acids (BCAAs) - oral supplementation and its effects in resistance training and treatment

Introduction: Branched - chain amino acids (BCAAs) are essential components of proteins that play a crucial role in regulating numerous physiological processes in the human body. This article provides a comprehensive analysis of scientific research on BCAAs, including their involvement in metabolism, protein biosynthesis, and the regulation of anabolic processes. We reviewed the supplementation of BCAAs and its impact on sports performance, body composition, and the therapeutic applications of BCAAs
 Materials and methods: This study is based on medical articles collected from the PubMed database spanning the years 2011-2023. The research was conducted through the analysis of keywords such as "BCAA supplementation", "BCAA metabolism", and "BCAA treatment".
 Results: The physiology of BCAAs is well understood. The use of oral supplements containing BCAAs does not have a positive impact on muscle hypertrophy, muscle strength, and post-workout muscle soreness in resistance training. However, branched chain amino acids may serve as a safe and effective therapeutic approach in the treatment of liver cirrhosis.

Oral administration of branched-chain amino acids ameliorates high-fat diet-induced metabolic-associated fatty liver disease via gut microbiota-associated mechanisms.

Branched-chain amino acids (BCAAs), essential amino acids for the human body, are mainly obtained from food. High levels of BCAAs in circulation are considered as potential markers of metabolic-associated fatty liver disease (MAFLD) in humans. However, there are conflicting reports about the effects of supplement of BCAAs on MAFLD, and research on BCAAs and gut microbiota is not comprehensive. Here, C57BL/6J mice were fed with a high-fat diet with or without BCAAs to elucidate the effects of BCAAs on the gut microbiota and metabolic functions in a mouse model of MAFLD. Compared to high-fat diet (HFD) feeding, BCAA supplementation significantly reduced the mouse body weight, ratio of liver/body weight, hepatic lipid accumulation, serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and alanine aminotransferase (ALT), and the expressions of the lipogenesis-related enzymes Fas, Acc, and Scd-1 and increased expressions of the lipolysis-related enzymes Cpt1A and Atgl in the liver. BCAAs supplementation also counteracted HFD-induced elevations in serum BCAAs levels by stimulating the enzymatic activity of BCKDH. Furthermore, BCAAs supplementation markedly improved the gut bacterial diversity and altered the gut microbiota composition and abundances, especially those of genera, in association with MAFLD and BCAAs metabolism. These data suggest that BCAA treatment improves HFD-induced MAFLD through mechanisms involving intestinal microbes.

Branched-chain amino acid supplementation impairs insulin sensitivity and promotes lipogenesis during exercise in diet-induced obese mice.

Branched-chain amino acids (BCAAs) are popular dietary supplements for exercise. However, increased BCAA levels positively correlate with obesity and diabetes. The metabolic impact of BCAA supplementation on insulin sensitivity during exercise is less understood. Male C57BL/6 mice were fed for 12 weeks with a high-fat diet, normal chow diet, or BCAA-restricted high-fat diet. They were subjected to running exercise with or without BCAA treatment for another 12 weeks. Exercise reduced body weight, improved insulin sensitivity, lowered BCAAs in plasma, and inhibited the upregulation of BCAAs and metabolites caused by BCAA supplementation in the subcutaneous white adipose tissue (sWAT) of obese mice. BCAA supplementation reversed insulin sensitivity ameliorated by exercise. The phosphorylation of protein kinase B (Ser473 and Ser474) was decreased by BCAAs in the sWAT of obese mice. However, BCAA supplementation had no such effects in lean mice. BCAAs also increased the expression of fatty acid synthase and other lipogenesis genes in the sWAT of exercised obese mice. BCAA restriction had no effect on body weight and insulin sensitivity in obese mice. BCAA supplementation impaired the beneficial effect of exercise on glycolipid metabolism in obese but not lean mice. Caution should be taken regarding the use of BCAAs for individuals with obesity who exercise.

A multivariate Box-Behnken assessment of elevated branched-chain amino acid concentrations in reduced crude protein diets offered to male broiler chickens.

In a Box-Behnken assessment of elevated branched-chain amino acids (BCAA), 13 nutritionally equivalent maize-based diets were offered to a total of 390 off-sex male Ross 308 broiler chickens from 7 to 28 days post-hatch. The BCAA concentrations investigated in reduced-crude protein diets were 12.5, 15.5, 18.3 g/kg leucine (125, 155, 183); 8.9, 10.2, 12.5 g/kg valine (89, 102, 125) and 7.2, 8.9, 10.8 g/kg isoleucine (72, 89, 109), where their relativity to 11.0 g/kg digestible lysine are shown in parentheses. Determined parameters included growth performance, relative abdominal fat-pad weights, nutrient utilisation, apparent digestibility coefficients, disappearance rates of 16 amino acids and free amino acid systemic plasma concentrations. Increasing dietary leucine linearly depressed weight gain and quadratically influenced FCR where the estimated minimum FCR of 1.418 was with 14.99 g/kg leucine. Polynomial regression analysis and surface response curves of determined parameters were generated for significant (P < 0.05) BCAA variables, based on lack of fit (P > 0.005). Quadratic and cross-product responses were observed for weight gain, FCR, AME, AMEn, N retention and apparent digestibility of 13 amino acids. Relative fat-pad weights declined linearly with increasing isoleucine and valine. The lowest N retention was estimated at a combination of 15.25 and 10.50 g/kg leucine and valine respectively whilst the highest mean digestibility coefficient (0.793) of amino acids was estimated at a combination of 15.74 and 10.47 g/kg of leucine and valine respectively. The remaining parameter minima or maxima responses were not able to be determined since they were outside the extreme BCAA treatment levels. Increasing dietary BCAA significantly increased apparent ileal digestibilities and disappearance rates of BCAA. Systemic plasma concentrations of valine increased (P < 0.001) with increasing dietary valine but leucine was not influenced (P > 0.25). Systemic plasma concentration of isoleucine was maximised (P < 0.001) only when accompanied by elevated dietary leucine. Also, dietary treatments influenced (P < 0.05) apparent disappearance rates of all the essential amino acids analysed, with the exception of methionine. Whilst overall growth performance was not disadvantaged (P > 0.10) by elevated BCAA levels, compared with 2019 Ross 308 performance objectives, polynomial regression analysis suggested both interaction and antagonism between BCAA.

Excess branched-chain amino acids alter myotube metabolism and substrate preference which is worsened by concurrent insulin resistance.

Branched-chain amino acids (BCAA) have been shown to enhance several cellular signaling pathways including protein synthesis and mitochondrial biogenesis, yet population data demonstrate a correlation between circulating BCAA and severity of insulin resistance which has been hypothesized to be, in part, a byproduct of BCAA inhibition of mitochondrial function. The purpose of this study is to examine the effect of a BCAA mixture on muscle metabolism and related gene expression in vitro. C2C12 myotubes were treated with a BCAA mixture containing leucine:isoleucine:valine at a ratio of 2:1:1 at 0.2, 2, or 20 mM (based on leucine content) for 6 days. qRT-PCR was used to measure metabolic gene expression. Oxygen consumption and extracellular acidification were used to assess mitochondrial and glycolytic metabolism, respectively. Mitochondrial content was determined via mitochondrial-specific staining. Despite significantly elevated mitochondrial staining, 6-day BCAA treatment reduced basal mitochondrial metabolism at a supraphysiological concentration (20 mM) in both insulin sensitive and resistant cells. Peak mitochondrial capacity was also reduced in insulin-resistant (but not insulin sensitive) cells. Conversely, basal glycolytic metabolism was elevated following 20 mM BCAA treatment, regardless of insulin resistance. In addition, insulin-resistant cells treated with 20 mM BCAA exhibited reduced gene expression of Ppargc1a, Cytc, Atp5b, Glut4, and several glycolytic enzymes versus insulin sensitive cells treated with 20 mM BCAA. Collectively, these findings suggest BCAA at supraphysiologically high levels may negatively alter mitochondrial metabolism, and concurrent insulin resistance may also diminish peak mitochondrial capacity, as well as impede molecular adaptations that support a transition to a glycolytic preference/compensation.

Supplementation with Branched-Chain Amino Acids Induces Unexpected Deleterious Effects on Astrocyte Survival and Intracellular Metabolism with or without Hyperammonemia: A Preliminary In Vitro Study.

Introduction Ammonia is a key component in the pathogenesis of hepatic encephalopathy. Branched-chain amino acids (BCAA) have been reported to improve the symptoms of HE induced by hyperammonemia; however, we recently reported that ammonia increases intracellular levels of BCAA and exerts toxic effects on astrocytes. Objectives This follow-up study was designed to confirm the direct effects of BCAA on human astrocytes and clarify their underlying mechanisms using metabolome analysis and evaluation of associated signaling. Methods We performed cytotoxicity and cell proliferation tests on astrocytes following BCAA treatment with and without ammonium chloride (NH4Cl) and then compared the results with the effects of BCAA on hepatocytes and neurons. Subsequently, we used metabolomic analysis to investigate intracellular metabolite levels in astrocytes with and without BCAA treatment. Results The astrocytes showed increased leakage of intracellular lactate dehydrogenase and reduced proliferation rate upon BCAA treatment. Interestingly, our analysis showed a BCAA-induced impairment of intracellular glycolysis/glyconeogenesis as well as amino acid and butyric acid metabolism. Furthermore, BCAA treatment was found to cause decreased levels of Glut-1 and phosphorylated GSK-3β and mTOR in astrocytes. Conclusions Although further investigations of the effect of BCAA on human astrocytes with hyperammonemia are needed, our work demonstrates that BCAA supplementation has direct negative effects on astrocyte survival and intracellular metabolism.

Branched-chain amino acids at supraphysiological but not physiological levels reduce myotube insulin sensitivity.

Branched-chain amino acids (BCAA) are often emphasized in the diets of avid exercisers, yet population data demonstrates a correlation between circulating BCAA and insulin resistance. However, it is unclear if BCAA independently promote insulin resistance in otherwise healthy cells. The purpose of this study is to examine the effect of a BCAA mixture on muscle insulin signaling in vitro in both insulin resistant and sensitive cells. C2C12 myotubes were treated with a BCAA mixture containing leucine:isoleucine:valine at a ratio of 2:1:1 at 0.2, 2, or 20mM (based on leucine content) for either 30min, 1day, or 6days. Western blot was used to assess insulin sensitivity of cells treated with BCAA both with and without concurrent insulin resistance, and, with and without insulin stimulation. BCAA treatment for 1day significantly reduced basal, but not insulin-stimulated pAkt expression. BCAA treatment for 6days resulted in significantly reduced basal insulin signaling in healthy cells and insulin-stimulated insulin signaling in insulin resistant (but not insulin sensitive) cells. Similar to previous observations demonstrating BCAA may correlate with insulin resistance during metabolically stressed conditions, we demonstrate excessively high BCAA exposure can negatively influence basal insulin signaling, as well as insulin sensitivity in insulin resistant myotubes. However, given the intentionally high concentrations of BCAA used in this study, the extent to which these observations translate to in vivo models is unclear and warrants further investigation.

BCAA Supplementation in Mice with Diet-induced Obesity Alters the Metabolome Without Impairing Glucose Homeostasis.

Circulating branched chain amino acid (BCAA) levels are elevated in obese humans and genetically obese rodents. However, the relationship of BCAAs to insulin resistance in diet-induced obese mice, a commonly used model to study glucose homeostasis, is still ill-defined. Here we examined how high-fat high-sucrose (HFHS) or high-fat diet (HFD) feeding, with or without BCAA supplementation in water, alters the metabolome in serum/plasma and tissues in mice and whether raising circulating BCAA levels worsens insulin resistance and glucose intolerance. Neither HFHS nor HFD feeding raised circulating BCAA levels in insulin-resistant diet-induced obese mice. BCAA supplementation raised circulating BCAA and branched-chain α-keto acid levels and C5-OH/C3-DC acylcarnitines (AC) in muscle from mice fed an HFHS diet or HFD, but did not worsen insulin resistance. A set of short- and long-chain acyl CoAs were elevated by diet alone in muscle, liver, and white adipose tissue (WAT), but not increased further by BCAA supplementation. HFD feeding reduced valine and leucine oxidation in WAT but not in muscle. BCAA supplementation markedly increased valine oxidation in muscle from HFD-fed mice, while leucine oxidation was unaffected by diet or BCAA treatment. Here we establish an extensive metabolome database showing tissue-specific changes in mice on 2 different HFDs, with or without BCAA supplementation. We conclude that mildly elevating circulating BCAAs and a subset of ACs by BCAA supplementation does not worsen insulin resistance or glucose tolerance in mice. This work highlights major differences in the effects of BCAAs on glucose homeostasis in diet-induced obese mice versus data reported in obese rats and in humans.

The effect of multi-ingredient intra- versus extra-cellular buffering supplementation combined with branched-chain amino acids and creatine on exercise-induced ammonia blood concentration and aerobic capacity in taekwondo athletes

BackgroundThis study aimed to investigate the effect of multi-ingredient intra- (BA) versus extra- (ALK) cellular buffering factor supplementation, combined with the customary intake of branched-chain amino acids (BCAA) and creatine malate (TCM), on body composition, exercise variables, and biochemical and hematological parameters in 9 elite taekwondo athletes.MethodsEight-week randomized double-blind crossover BA (5.0 g·day−1 of β-alanine) versus ALK (0.07 g·kgFFM−1·day−1 of sodium bicarbonate) supplementation combined with BCAA (0.2 g·kgFFM−1·day−1) and TCM (0.05 g·kgFFM−1·day−1) during a standard 8-week taekwondo training period was implemented. In the course of the experiment, body composition (dual X-ray absorptiometry), aerobic capacity (ergospirometric measurements during an incremental treadmill test until exhaustion), and exercise blood biomarkers concentrations were measured. Data were analyzed using repeated measures within-between interaction analysis of variance with the inclusion of experimental supplementation order.ResultsThe maximum post-exercise blood ammonia concentration decreased in both groups after supplementation (from 80.3 ± 10.6 to 72.4 ± 10.2 µmol∙L−1, p = 0.013 in BA; from 81.4 ± 8.7 to 74.2 ± 8.9 µmol∙L−1, p = 0.027 in ALK), indicating reduced exercise-related adenosine triphosphate degradation. However, no differences were found in body composition, aerobic capacity, blood lactate concentration, and hematological parameters after neither BA (combined with BCAA and TCM) nor ALK (combined with BCAA and TCM) supplementation.ConclusionsIn highly trained taekwondo athletes, neither extra- nor intracellular buffering enhancement resulting from BA and ALK supplementation, combined with BCAA and TCM treatment, affects body mass and composition, maximum oxygen uptake, and hematological indices, even though certain advantageous metabolic adaptations can be observed.

Branched-chain amino acids and l-carnitine attenuate lipotoxic hepatocellular damage in rat cirrhotic liver

Branched-chain amino acids (BCAA) reverse malnutrition and l-carnitine leads to the reduction of hyperammonemia and muscle cramps in cirrhotic patients. BCAA and l-carnitine are involved in glucose and fatty acid metabolism, however their mechanistic activity in cirrhotic liver is not fully understood. We aim to define the molecular mechanism(s) and combined effects of BCAA and l-carnitine using a cirrhotic rat model. Rats were administered carbon tetrachloride for 10 weeks to induce cirrhosis. During the last 6 weeks of administration, cirrhotic rats received BCAA, l-carnitine or a combination of BCAA and l-carnitine daily via gavage. We found that BCAA and l-carnitine treatments significantly improved hepatocellular function associated with reduced triglyceride level, lipid deposition and adipophilin expression, in cirrhotic liver. Lipidomic analysis revealed dynamic changes in hepatic lipid composition by BCAA and l-carnitine administrations. BCAA and l-carnitine globally increased molecular species of phosphatidylcholine. Liver triacylglycerol and phosphatidylcholine hydroperoxides were significantly decreased by BCAA and l-carnitine. Furthermore, serum and liver ATP levels were significantly increased in all treatments, which were attributed to the elevation of mature cardiolipins and mitochondrial component gene expressions. Finally, BCAA and l-carnitine dramatically reduced hepatocellular death. In conclusion, BCAA and l-carnitine treatments attenuate hepatocellular damage through the reduction of lipid peroxides and the overall maintenance of mitochondrial integrity within the cirrhotic liver. These effectiveness of BCAA and l-carnitine support the therapeutic strategies in human chronic liver diseases.

Current Practice of Branched Chain Amino Acids Administration in Patients with Liver Cirrhosis: A Physician Survey

Introduction: Protein Energy Malnutrition (PEM) is prevalent in about 65-90% of patients with liver disorders. PEM is usually associated with poor quality of life, high risk of complications, morbidity and mortality, and longer duration of hospital stays. PEM is also associated with decreased skeletal muscle mass and reduced levels of serum albumin and Branched Chain Amino Acids (BCAAs). Therefore, BCAAs are recommended as nutritional therapy in various liver disorders. Aim: To understand the current practice of BCAA use in patients with liver cirrhosis in India. Materials and Methods: A cross-sectional, questionnaire-based survey was conducted pan India involving 100 gastroenterologists over a period of four months from September 2019 to December 2019. Each physician participated in the survey after verbal consent. Ample time was given for completion of the questionnaires. Results: Out of 83 participating physicians, nearly 3/4th considered liver cirrhosis as the most common Gastrointestinal (GI) disorder where nutrition is important in patient management. Malnutrition was commonly observed in patients with cirrhosis by nearly over 80% physicians and was most common in patients with decompensated cirrhosis. Weight loss and loss of appetite can be early signs of sarcopenia as these were common profiles observed in patients with malnutrition. Total 51.8% physicians considered BCAA administration in all Child-Pugh class patients. The practice of BCAA treatment with regards to its dose and duration highly varied for patients with cirrhosis, Hepatic Encephalopathy (HE), and Liver Transplantation (LT). Proteins from vegetarian source (50.6%) and BCAA supplementation (96.4%) were considered as major treatments for HE patients. Majority of the physicians reported that BCAA administration improved quality of life (52.4%), reduced HE episodes (49.4%), improved muscle mass (50%), and reduced hospitalisation rates (49.4%) in 20-40% of their patients. In all, 92.8% of physicians suggested that early administration of oral BCAA can prolong the waiting period for LT. Conclusion: Branched Chain Amino Acids (BCAA) is an integral part of nutritional management in patients with liver cirrhosis in India. Further studies are required to guide the decision on dose and duration of BCAA treatment in the management of cirrhosis.

Supplementation of branched-chain amino acids decreases fat accumulation in the liver through intestinal microbiota-mediated production of acetic acid

Non-alcoholic fatty liver disease (NAFLD) is a significant problem because its prevalence is increasing worldwide. Recent animal studies have identified gut microbiota as a potentially important player in the pathogenesis of NAFLD. Previously, we reported that the administration of branched-chain amino acids (BCAAs) reduces hepatic fat accumulation in experimental animal models. This study aimed to clarify how changes in the intestinal microbial flora following the administration of BCAAs affect a high-fat diet (HF)-induced fat accumulation in the liver. We examined whether the administration of BCAAs alters the development of hepatic fat accumulation as well as intestinal microbial flora. The oral administration of BCAAs (3% kcal) induced a significant increase in Ruminococcus flavefaciens (R. flavefaciens) and portal acetic acid levels, and it reduced hepatic fat accumulation in HF-fed rats. In addition, BCAAs reduced the expression of the lipogenesis-related genes FAS and ACC in the liver. Furthermore, we observed that R. flavefaciens is essential for promoting a BCAA-induced reduction in hepatic fat accumulation. These data suggest that BCAA treatment induces the proliferation of intestinal flora including R. flavefaciens and that portal acetic acid synthesized from intestinal flora improves NAFLD by downregulating the expression of FAS and ACC in the liver.

Excessive ROS production and enhanced autophagy contribute to myocardial injury induced by branched-chain amino acids: Roles for the AMPK-ULK1 signaling pathway and α7nAChR

Backgrounds and aimsLeucine, isoleucine, and valine are diet derived and essential amino acids that are termed branched-chain amino acids (BCAA). BCAA are widely used as dietary supplements to boost muscle growth and enhance exercise performance. However, the effects of BCAA on myocardial function are largely unknown. This study was designed to investigate whether BCAA affect heart function and, if so, to further explore the underlying molecular basis for the observed effects. Methods and resultsC57BL/6J mice were randomly divided into two groups, the control group received solvent (water) and the BCAA group received 2% BCAA dissolved in water, for a successive period of 12 weeks. Compared with control, BCAA treatment significantly increased water consumption without changing body weight or diet consumption; heart tissue BCAA levels were increased, markers representative of myocardial injury in heart tissue including c-reactive protein and cardiac muscle troponin were increased ; and creatine kinase, creatine kinase-MB, and lactate dehydrogenase were increased in serum; severe myocardial fibrosis was observed by Masson staining, which was accompanied by increased reactive oxygen species (ROS) production and decreased superoxide dismutase activity in heart tissue; both p-AMPK and p-ULK1 were significantly increased as was autophagy, judged by the presence of LC3 by western blotting and immunofluorescence, increased numbers of autophagosomes were found by transmission electron microscopy in the BCAA group. In vitro, 20 mmol/L BCAA significantly decreased cell viability and increased the production of ROS, as well as the expression of p-AMPK/AMPK and p-ULK1/ULK1 in cultured H9C2 cells. Treatment with the ROS scavenger N-acetyl-L-cysteine (NAC) improved cell viability and reversed ROS changes. Decreased H9C2 cell viability induced with 20 mmol/L BCAA was reversed by either blocking AMPK or inhibition of ULK1. Furthermore, blocking AMPK significantly decreased p-ULK1/ULK1, while inhibition of ULK1 reversed the enhanced expression of LC3-II/LC3-I induced by BCAA. Excessive ROS production and decreased cell viability induced by BCAA were further confirmed in primary cultured murine cardiomyocytes. Pharmacological activation of α7nAChR with PNU-282987 attenuated BCAA-induced injury in primary murine cardiomyocytes. However, this compound failed to suppress BCAA activation of AMPK and autophagy (LC3-II/I ratio). ConclusionThese results provide the first evidence that treatment of mice with BCAA induced myocardial injury by triggering excessive ROS production and by enhancing AMPK-ULK1 pathway-dependent autophagy. These findings suggested that inhibition of either ROS production or autophagy may alleviate myocardial injury induced by BCAA.

Anti-fibrotic effects of branched-chain amino acids on hepatic stellate cells.

Background/AimsPatients with liver cirrhosis (LC) have low levels of branched-chain amino acids (BCAAs). There is accumulating evidence that BCAAs have anti-fibrotic effects in cirrhosis. This study is aimed to evaluate the effect of BCAAs on the function and phenotype of activated hepatic stellate cells (HSCs).MethodsLX-2, an immortalized human stellate cell line, was used in in vitro experiments. LX-2 cells were exposed to transforming growth factor β1 (TGF-β1) and BCAAs or to valine, leucine, and isoleucine, which are components of BCAAs. Activation of the TGF-β signaling pathway in LX-2 cells was observed using real-time quantitative polymerase chain reaction and Western blotting.ResultsThe increased expression of snail family transcriptional repressor 1 (SNAI1) was observed in LX-2 cells activated by TGF-β1. After BCAA treatment, its expression was significantly decreased at the mRNA level. The increased expression of Col1α1 and TIMP2 at the mRNA level and alpha smooth muscle actin at the protein level in activated LX-2 cells decreased after BCAA treatment. Among the BCAA components, leucine and valine significantly abrogated TGF-β-induced activation of LX-2 cells. BCAA treatment led to the decreased phosphorylation of Smad2 and p38 proteins, which are markers for Smad and Smad-independent p38 mitogen-activated protein kinase signaling pathways, respectively.ConclusionsBCAA treatment can improve hepatic fibrosis by directly affecting the activated state of hepatic stellate cells through inhibition of the TGF-β signaling pathway. Among BCAA components, leucine and valine mainly abrogated TGF-β-induced activation of HSCs. Our results suggest that BCAA may be used to attenuate the progression of liver fibrosis.

Amino acids‐induced cardiac protection by promoting mitochondrial function via mTOR and Opa‐1 signaling

ObjectsAmino acids, especially branched chain amino acids (BCAAs), have important regulatory roles in protein synthesis. Recently studies revealed that BCAAs protect against ischemia/reperfusion (I/R) injury. We studied the signaling pathway and mitochondrial function affecting a cardiac preconditioning of BCAAs.MethodsCardiac myocytes were isolated by cardiac retrograde aortic perfusion and collagenase and were subjected to simulated ischemia and cell death was quantified. Immunoblot and real time PCR were performed as biochemical assay and mitochondrial function was assessed using Seahorse XF cell Mito test.ResultsIn myocytes undergoing simulated I/R, BCAA treatment significantly preserved cell viability (71.7 ± 2.7% vs. 34.5 ± 1.6%, respectively, p &lt; 0.0001), whereas rapamycin prevented this BCAA‐induced cardioprotective effect (43.5 ± 3.4% vs. BCAA, p &lt; 0.0001). To elucidate the mechanism, we assessed changes in the mitochondrial fusion regulators Opa‐1, Mfn‐1, and Mfn‐2. BCAA treatment increased expression of Opa‐1, but not Mfn‐1 or Mfn‐2. Enhanced mitochondrial fusion also improved mitochondrial function including oxygen consumption rate.ConclusionsBCAA acutely regulates mitochondrial metabolism in cardiomyocytes and increased mitochondrial fusion, Opa‐1, and the Akt‐mTOR pathway, offering a novel target for prevention and treatment of coronary disease.Support or Funding InformationThis study was supported by Japan Society of Promotion Science #19K09353 to YMT.

Utilizing Branched-chain Amino Acids for Increasing Shoot Density and Establishment Rate in Creeping Bentgrass

The branched-chain amino acids (BCAA) leucine (L), isoleucine (IL), and valine (V) are synthesized in plants and are essential to growth in most organisms. These compounds can be absorbed by the plant when foliarly applied, but plant catabolism of BCAA is not completely understood. A recent study observed that BCAA applied in a 2:1:1 or 4:1:1 ratio (L:IL:V) increased creeping bentgrass (Agrostis stolonifera) shoot density compared with applications of equal urea nitrogen (N) at 3.03 lb/acre N. The present study investigated whether those increases could translate to a quicker establishment rate of creeping bentgrass grown from seed in standard greenhouse pots. The BCAA applications were compared with equal N applications using urea and a commercially available amino acid product. All N treatments were applied at 3.03 lb/acre N, per application and applied a total of four times on a 14-day interval starting 14 days after seeding. Measurements included final shoot density counts and root and shoot weights, as well as digital image analysis of percent green cover for each greenhouse pot every 7 days. No differences were observed after 70 days in shoot weight, or percent green cover between BCAA treatments and urea; however, BCAA 2:1:1 and 4:1:1 increased shoot density 21% and 30%, respectively, compared with urea, and were equal to the commercially available amino acid product. Applications of BCAA 4:1:1 also increased creeping bentgrass rooting weight by a factor of 7 compared with urea N.

Branched-chain amino acids-induced cardiac protection against ischemia/reperfusion injury

AimsAmino acids, especially branched chain amino acids (BCAAs), have important regulatory roles in protein synthesis. Recently studies revealed that BCAAs protect against ischemia/reperfusion (I/R) injury. We studied the signaling pathway and mitochondrial function affecting a cardiac preconditioning of BCAAs. Main methodsAn in vivo model of I/R injury was tested in control, mTOR+/+, and mTOR+/−. Mice were randomly assigned to receive BCAAs, rapamycin, or BCAAs + rapamycin. Furthermore, isolated cardiomyocytes were subjected to simulated ischemia and cell death was quantified. Biochemical and mitochondrial swelling assays were also performed. Key findingsMice treated with BCAAs had a significant reduction in infarct size as a percentage of the area at risk compared to controls (34.1 ± 3.9% vs. 44.7 ± 2.6%, P = 0.001), whereas mice treated with the mTOR inhibitor rapamycin were not protected by BCAA administration (42.2 ± 6.5%, vs. control, P = 0.015). This protection was not detected in our hetero knockout mice of mTOR. Western blot analysis revealed no change in AKT signaling whereas activation of mTOR was identified. Furthermore, BCAAs prevented swelling which was reversed by the addition of rapamycin. In myocytes undergoing simulated I/R, BCAA treatment significantly preserved cell viability (71.7 ± 2.7% vs. 34.5 ± 1.6%, respectively, p < 0.0001), whereas rapamycin prevented this BCAA-induced cardioprotective effect (43.5 ± 3.4% vs. BCAA, p < 0.0001). SignificanceBCAA treatment exhibits a protective effect in myocardial I/R injury and that mTOR plays an important role in this preconditioning effect.

From mitochondria to healthy aging: The role of branched-chain amino acids treatment: MATeR a randomized study.

Malnutrition often affects elderly patients and significantly contributes to the reduction in healthy life expectancy, causing high morbidity and mortality. In particular, protein malnutrition is one of the determinants of frailty and sarcopenia in elderly people. To investigate the role of amino acid supplementation in senior patients we performed an open-label randomized trial and administered a particular branched-chain amino acid enriched mixture (BCAAem) or provided diet advice in 155 elderly malnourished patients. They were followed for 2 months, assessing cognitive performance by Mini Mental State Examination (MMSE), muscle mass measured by anthropometry, strength measure by hand grip and performance measured by the Timed Up and Go (TUG) test, the 30s Chair Sit to Stand (30-s CST) test and the 4m gait speed test. Moreover we measured oxidative stress in plasma and mitochondrial production of ATP and electron flux in peripheral blood mononuclear cells. Both groups improved in nutritional status, general health and muscle mass, strength and performance; treatment with BCAAem supplementation was more effective than simple diet advice in increasing MMSE (1.2 increase versus 0.2, p=0.0171), ATP production (0.43 increase versus-0.1, p=0.0001), electron flux (0.50 increase versus 0.01, p<0.0001) and in maintaining low oxidative stress. The amelioration of clinical parameters as MMSE, balance, four meter walking test were associated to increased mitochondrial function. Overall, our findings show that sustaining nutritional support might be clinically relevant in increasing physical performance in elderly malnourished patients and that the use of specific BCAAem might ameliorate also cognitive performance thanks to an amelioration of mitochondria bioenergetics.

Abstract 4188: Preoperative supplementation of branched-chain amino acids suppresses Osteopontin expression in patients with hepatocellular carcinoma

Abstract Background: Recently, the new effect of branched-chain amino acid (BCAA) on Osteopontin (OPN), which correlates with cancer progression, has been reported. The aim of this study was that preoperative administration of BCAA could improve prognosis via degradation of OPN expression in hepatocellular carcinoma (HCC). Methods: Human hepatocellular carcinoma cell lines were treated with BCAA (2nM), and investigated OPN expression, cell proliferation and invasion in vitro. Next, patients undergoing elective liver resections for HCC (n=72) were randomized to receive or not receive preoperative oral supplementation with BCAA. OPN protein levels in HCC patients were examined using immunohistochemistry and compared with the clinicopathologic features of the tumors. Results: Experimentally, the expression levels of OPN were significantly decreased in HCC cells treated with BCAA. BCAA treatment significantly decreased cell invasion. In the clinical setting, OPN expression correlated with HBV or HCV infection (p = 0.03), venous invasion (p = 0.02) and liver fibrosis (p = 0.07). There was no difference in both DFS and OS between OPN-positive and OPN-negative group, and preoperative BCAA administration did not improve prognosis, either. For the patients without late recurrence, OPN-positive group showed significantly poor outcome in DFS (p = 0.047), and preoperative BCAA administration improved DFS (p = 0.062). Conclusions: OPN expression was associated with cancer cell invasion and intrahepatic metastasis. BCAA treatment suppressed HCC cell invasion and preoperative BCAA administration prevented early intrahepatic recurrence by decreasing the expression level of OPN in HCC. Citation Format: Yukihiko Hiroshima, Yasuhiro Yabushita, Yutaro Kikuchi, Daisuke Kawagushi, Takashi Murakami, Yasushi Ichikawa, Itaru Endo, Kuniya Tanaka. Preoperative supplementation of branched-chain amino acids suppresses Osteopontin expression in patients with hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4188.