Dietary intake of branched-chain amino acids and colorectal cancer risk

ABSTACTAn adequate intake of branched-chain amino acids (BCAAs) is required for protein synthesis and metabolic functions, including insulin metabolism. Emerging studies found positive associations between BCAAs and the risk of various diseases sharing etiological aspects with colorectal cancer (CRC), including type 2 diabetes, obesity, and pancreatic cancer.We investigated the relation between dietary BCAAs and CRC using data from a multicentric Italian case-control study, including 1953 cases of CRC (of these, 442 of sigmoid colon) and 4154 hospital controls with acute, non-neoplastic diseases. A validated food-frequency questionnaire was used to estimate the participants' usual diet and to assess dietary intakes of various nutrients, including energy, BCAAs and calcium. Odds ratio (ORs) and corresponding confidence intervals (CI) were computed by multiple logistic regression models adjusted for age, sex and other confounding factors, including total energy intake.BCAA intake was inversely related to CRC risk (OR for the highest versus the lowest quintile, 0.73; 95% CI, 0.55-0.97), but the association was attenuated after adjustment for calcium intake (OR, 0.90; 95% CI, 0.65-1.25). A linear inverse association with sigmoid colon cancer risk remained also after adjustment for other dietary factors, including calcium intake (OR, 0.49; 95% CI, 0.27-0.87).This study provides supporting evidence that higher levels of dietary BCAA intake are not associated with an increase of CRC risk, but confirms that they may be related to a reduced risk of sigmoid colon cancer

Branched-Chain Amino Acids

Our study is focused on evaluation and use of the most effective and correct nutrients. In particular, our attention is directed to the role of certain amino acids in cachectic patients.During parenteral nutrition in humans, physician already associates in the PN-bags different formulations including amino acids, lipids and glucose solutions or essential amino acids solution alone or exclusively branched-chain amino acids (BCAA). Studies investigated the effects of dietary BCAA ingestion on different diseases and conditions such as obesity and metabolic disorders, liver disease, muscle atrophy, cancer, impaired immunity or injuries (surgery, trauma, burns, and sepsis). BCAAs have been shown to affect gene expression, protein metabolism, apoptosis and regeneration of hepatocytes, and insulin resistance. They have also been shown to inhibit the proliferation of liver cancer cells in vitro, and are essential for lymphocyte proliferation and dendritic cell maturation. Oral or parenteral administration of these three amino acids will allow us to evaluate the real efficacy of these compounds during a therapy to treat malnutrition in subjects unable to feed themselves

Correlation Between Branched Chain Amino Acids to Tyrosine Ratio and Child Pugh Score in Liver Cirrhosis Patients

Background: The determination of branched chain amino acids (BCAA) to tyrosine ratio (BTR) was available in making differentiation of chronic hepatitis from liver cirrhosis, because there was a strong association between BTR and staging (fibrosis) scores. Branched chain amino acids to tyrosine ratio have a correlation with Fischer ratio and the examination is easier because it can be done by enzymatic assay. Materials and Methods: To evaluate the correlation between BTR and Child-Pugh score, we examined the amino gram of 52 liver cirrhosis patients consisted of 26 Child-Pugh A, 19 Child-Pugh B, and 7 Child-Pugh C. The examination of amino gram was done by High Pressure Liquid Chromatograph (HPLC) analyzer. Branched chain amino acids to tyrosine ratio were compared to Child-Pugh score, albumin, ammonia level, number connection test to Fischer ratio. Results: Significant differences in BTR among Child-Pugh A, B, C were observed (Child-Pugh A 7.75 + 1.2; Child Pugh B 6.0 + 1.23 and Child Pugh C 4.38 + 3.14 (p = 0.000)). Branched chain amino acids to tyrosine ratio had a weak correlation with albumin (r = 0.292; p = 0.036), ammonia level (r = 0.376; p = 0.006) and strong correlation with Fischer ratio (r = 0.818; p = 0.000). There was no significant correlation between BTR and number connection test. Conclusion: These results showed that the determination of the molar ratio of branched chain amino acids to tyrosine well reflected the severity of liver cirrhosis and it can be used as a substitute of Fischer ratio

Branched chain amino acids, an ''essential'' link between diet, clock and sleep?

The branched-chain amino acids: leucine, isoleucine and valine occupy a special place among the essential amino acids because of their importance not only in the structure of proteins but also in general and cerebral metabolism. Among the first amino acids absorbed after food intake, they play a major role in the regulation of protein synthesis and insulin secretion. They are involved in the modulation of brain uptake of monoamine precursors with which they may compete for occupancy of a common transporter. In the brain, branched-chain amino acids are involved not only in protein synthesis but also in the metabolic cycles of GABA and Glutamate, and in energy metabolism. In particular, they can affect GABAergic neurons and the excitation/inhibition balance. Branched-chain amino acids are known for the 24-hour rhythmicity of their plasma concentrations, which is remarkably conserved in rodent models. This rhythmicity is partly circadian, independent of sleep and food. Moreover, their concentration increases when sleep is disturbed and in obesity and diabetes. The mechanisms regulating these rhythms and their physiological impact remain poorly understood. In this context, the Drosophila model has not yet been widely used, but it is highly relevant and the first results indicate that it can generate new concepts. The elucidation of the metabolism and fluxes of branched-chain amino acids is beginning to shed light on the mysterious connections between clock, sleep, and metabolism, opening the possibility of new therapies

In vitro branched chain amino acid oxidation by porcine mammary tissue

Mammary secretory tissue from six (three each of parity 1 and 2) lactating sows (d 10 to 17 of lactation) was obtained via biopsy for in vitro incubation to determine CO2 production fr01TI individual branched chain amino acids. Carbon dioxide production levels as percentages of the 14C-labeled amino acid metabolized by the mammary tissue were 2.57, 1.86, and 4.07% for isoleucine, leucine, and valine, respectively (P\u3c .03). These results indicate that, in the lactating sow mammary gland, valine has the greatest oxidation rate of the branched chain amino acids.; Swine Day, Manhattan, KS, November 16, 199

Amino Acid Accumulation Limits the Overexpression of Proteins in Lactococcus lactis

Background: Understanding the biogenesis pathways for the functional expression of recombinant proteins, in particular membrane proteins and complex multidomain assemblies, is a fundamental issue in cell biology and of high importance for future progress in structural genomics. In this study, we employed a proteomic approach to understand the difference in expression levels for various multidomain membrane proteins in L. lactis cells grown in complex and synthetic media. Methodology/Principal Findings: The proteomic profiles of cells growing in media in which the proteins were expressed to high or low levels suggested a limitation in the availability of branched-chain amino acids, more specifically a too limited capacity to accumulate these nutrients. By supplying the cells with an alternative path for accumulation of Ile, Leu and/or Val, i.e., a medium supplement of the appropriate dipeptides, or by engineering the transport capacity for branched-chain amino acids, the expression levels could be increased several fold. Conclusions: We show that the availability of branched chain amino acids is a critical factor for the (over) expression of proteins in L. lactis. The forward engineering of cells for functional protein production required fine-tuning of co-expression of the branched chain amino acid transporter

“Avaliação do uso de ergogênicos por praticantes de academia no Noroeste e Nordeste do estado de São Paulo”

This study aims to analyze the profile of physical activity practitioners that makes use of ergogenic dietary supplements, based on gender, age, body mass index ( BMI), education and nutritional supplements used. 229 practitioners were surveyed in 7 cities of the in Northeast and Northwest of São Paulo : Ribeirão Preto , Jaboticabal, Cajuru, Taquaritinga , Catanduva , São José do Rio Preto and Pindorama . Of these 229, 100 43.6%) used nutritional ergogenic , 69 (69%) men and 31 (31%) women . The average age was 26.8 years with a minimum and maximum values respectively, of 15 and 60 years old; The main BMI was 24.95; and prevalent schooling was complete or incomplete Higher Education (being composed of students). The most often used supplements were : rich in protein (73%), branched chain amino acids (36%), carbohydrate (35%) and creatine (29%); reminding that users could consume more tahn one nutritional ergogenic. In the male group , the most commonly used supplements were high in protein (80%), branched chain amino acids (39%), carbohydrate (39%) and creatine (36%); however the female group supplements were rich in protein (58%), fat burners (32%), branched chain amino acids (29%) and carbohydrate (26%). The general profile of the user points to a young - adult individual aged between 20-30 years old of higher education and BMI of 24.9 kg / m, showing both physical and nutritional concerns

Volatile profiling reveals intracellular metabolic changes in Aspergillus parasticus: veA regulates branched chain amino acid and ethanol metabolism

Background: Filamentous fungi in the genus Aspergillus produce a variety of natural products, including aflatoxin, the most potent naturally occurring carcinogen known. Aflatoxin biosynthesis, one of the most highly characterized secondary metabolic pathways, offers a model system to study secondary metabolism in eukaryotes. To control or customize biosynthesis of natural products we must understand how secondary metabolism integrates into the overall cellular metabolic network. By applying a metabolomics approach we analyzed volatile compounds synthesized by Aspergillus parasiticus in an attempt to define the association of secondary metabolism with other metabolic and cellular processes. Results: Volatile compounds were examined using solid phase microextraction - gas chromatography/mass spectrometry. In the wild type strain Aspergillus parasiticus SU-1, the largest group of volatiles included compounds derived from catabolism of branched chain amino acids (leucine, isoleucine, and valine); we also identified alcohols, esters, aldehydes, and lipid-derived volatiles. The number and quantity of the volatiles produced depended on media composition, time of incubation, and light-dark status. A block in aflatoxin biosynthesis or disruption of the global regulator veA affected the volatile profile. In addition to its multiple functions in secondary metabolism and development, VeA negatively regulated catabolism of branched chain amino acids and synthesis of ethanol at the transcriptional level thus playing a role in controlling carbon flow within the cell. Finally, we demonstrated that volatiles generated by a veA disruption mutant are part of the complex regulatory machinery that mediates the effects of VeA on asexual conidiation and sclerotia formation. Conclusions: 1) Volatile profiling provides a rapid, effective, and powerful approach to identify changes in intracellular metabolic networks in filamentous fungi. 2) VeA coordinates the biosynthesis of secondary metabolites with catabolism of branched chain amino acids, alcohol biosynthesis, and b-oxidation of fatty acids. 3) Intracellular chemical development in A. parasiticus is linked to morphological development. 4) Understanding carbon flow through secondary metabolic pathways and catabolism of branched chain amino acids is essential for controlling and customizing production of natural products

Branched Chain Amino Acids: Causal or Predictive of Type 2 Diabetes

Branched Chain Amino Acids (BCAA) have been associated with insulin resistance and type 2 diabetes. However, there is not concrete understanding on whether BCAA is playing a causal factor or a predictive factor for type 2 diabetes. The aim of this review is to understand how Branched Chain Amino Acids act as a predictive biomarker of type 2 diabetes (T2D) or causal factor in insulin resistance. Two mechanisms have been proposed, but not enough studies have been done to prove which is true. There is still a lot of unknowns in BCAA mechanisms and how it affects metabolic disorders. Future study recommendations have been made to further understand BCAA pertaining to T2D and other metabolic disorders. After reviewing current studies, there is not enough evidence to confirm whether BCAAs are causative or predictive of T2D

Branched‐Chain Amino Acids in Patients With Hepatic Encephalopathy

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142130/1/ncp0097.pd