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ObjectiveWe conducted a two-sample Mendelian randomization （MR） study to assess the causal relationship between circulating isoleucine， leucine and valine levels and the risk of peripheral atherosclerosis. MethodsBased on the large-scale genome-wide association study （GWAS） database， single nucleotide polymorphisms （SNPs） closely related to the circulating levels of isoleucine， leucine and valine were identified as instrumental variables （IVs）. Two-sample MR analysis applying the inverse variance weighted （IVW） method and the weighted median estimator （WME） method were performed to estimate the causal relationship between the risk of peripheral atherosclerosis and the exposure with more than three SNPs that were available as IVs. The pleiotropy was evaluated by using the MR-Egger regression and MR-PRESSO method， and the leave-one-out method was used in sensitivity analysis. ResultsFour， one and one SNPs were identified as IVs for circulating isoleucine， leucine and valine levels， respectively. For isoleucine， the IVW model demonstrated there was no evidence of heterogeneity among the IVs （P=0.715）， and there was a significant causal relationship between the increase of circulating isoleucine level and a higher risk of peripheral atherosclerosis risk. Per every 1 elevated standard deviation （SD） of circulating isoleucine level resulted in increasing 31% of peripheral atherosclerosis risk （OR=1.31， 95%CI： 1.07‒1.61）. Similarly， the OR（95%CI） was 1.33 （1.04‒1.71） in the WME model. The MR-Egger regression and MR-PRESSO analysis indicated no evidence of pleiotropy in IVs （all P>0.05）. The result of the leave-one-out sensitivity analysis was stable. The Wald ratio model displayed that the causal relationship between circulating leucine and valine levels and the risk of peripheral atherosclerosis was not statistically significant. The OR （95%CI） for leucine and valine was 1.13 （0.78‒1.63） and 1.11 （0.82‒1.50）， respectively. ConclusionThere is a significant causal relationship between the increase of circulating isoleucine level and a higher peripheral atherosclerosis risk. The causal relationships between circulating leucine and valine levels and the risk of peripheral atherosclerosis need to be further confirmed in future studies.
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OBJECTIVES@#Multiple myeloma (MM) is a plasma cell malignancy occurring in middle and old age. MM is still an incurable disease due to its frequent recurrence and drug resistance. However, its pathogenesis is still unclear. Abnormal amino acid metabolism is one of the important characteristics of MM, and the important metabolic pathway of amino acids participates in protein synthesis as basic raw materials. Aminoacyl transfer ribonucleic acid synthetase (ARS) gene is a key regulatory gene in protein synthesis. This study aims to explore the molecular mechanism for ARS, a key factor of amino acid metabolism, in regulating amino acid metabolism in MM and affecting MM growth.@*METHODS@#The corresponding gene number was combined with the gene expression profile GSE5900 dataset and GSE2658 dataset in Gene Expression Omnibus (GEO) database to standardize the gene expression data of ARS. GSEA_4.2.0 software was used to analyze the difference of gene enrichment between healthy donors (HD) and MM patients in GEO database. GraphPad Prism 7 was used to draw heat maps and perform data analysis. Kaplan-Meier and Cox regression model were used to analyze the expression of ARS gene and the prognosis of MM patients, respectively. Bone marrow samples from 7 newly diagnosed MM patients were collected, CD138+ and CD138- cells were obtained by using CD138 antibody magnetic beads, and the expression of ARS in MM clinical samples was analyzed by real-time RT-PCR. Human B lymphocyte GM12878 cells and human MM cell lines ARP1, NCI-H929, OCI-MY5, U266, RPMI 8266, OPM-2, JJN-3, KMS11, MM1.s cells were selected as the study objects. The expression of ARS in MM cell lines was analyzed by real-time RT-PCR and Western blotting. Short hairpin RNA (shRNA) lentiviruses were used to construct gene knock-out plasmids (VARS-sh group). No-load plasmids (scramble group) and gene knock-out plasmids (VARS-sh group) were transfected into HEK 293T cells with for virus packaging, respectively. Stable expression cell lines were established by infecting ARP1 and OCI-MY5 cells, and the effects of knockout valyl-tRNA synthetase (VARS) gene on proliferation and apoptosis of MM cells were detected by cell counting and flow cytometry, respectively. GEO data were divided into a high expression group and a low expression group according to the expression of VARS. Bioinformatics analysis was performed to explore the downstream pathways affected by VARS. Gas chromatography time-of-flight mass spectrometry (GC-TOF/MS) and high performance liquid chromatography (HPLC) were used to detect the valine content in CD138+ cells and ARP1, OCI-MY5 cells and supernatant of knockdown VARS gene in bone marrow samples from patients, respectively.@*RESULTS@#Gene enrichment analysis showed that tRNA processing related genes were significantly enriched in MM compared with HD (P<0.0001). Further screening of tRNA processing-pathway related subsets revealed that cytoplasmic aminoacyl tRNA synthetase family genes were significantly enriched in MM (P<0.0001). The results of gene expression heat map showed that the ARS family genes except alanyl-tRNA synthetase (AARS), arginyl-tRNA synthetase (RARS), seryl-tRNA synthetase (SARS) in GEO data were highly expressed in MM (all P<0.01). With the development of monoclonal gammopathy of undetermined significance (MGUS) to MM, the gene expression level was increased gradually. Kaplan-Meier univariate analysis of survival results showed that there were significant differences in the prognosis of MM patients in methionyl-tRNA synthetase (MARS), asparaginyl-tRNA synthetase (NARS) and VARS between the high expression group and the low expression group (all P<0.05). Cox regression model multivariate analysis showed that the high expression of VARS was associated with abnormal overall survival time of MM (HR=1.83, 95% CI 1.10 to 3.06, P=0.021). The high expression of NARS (HR=0.90, 95% CI 0.34 to 2.38) and MARS (HR=1.59, 95% CI 0.73 to 3.50) had no effect on the overall survival time of MM patients (both P>0.05). Real-time RT-PCR and Western blotting showed that VARS, MARS and NARS were highly expressed in CD138+ MM cells and MM cell lines of clinical patients (all P<0.05). Cell counting and flow cytometry results showed that the proliferation of MM cells by knockout VARS was significantly inhibited (P<0.01), the proportion of apoptosis was significantly increased (P<0.05). Bioinformatics analysis showed that in addition to several pathways including the cell cycle regulated by VARS, the valine, leucine and isoleucine catabolic pathways were upregulated. Non-targeted metabolomics data showed reduced valine content in CD138+ tumor cells in MM patients compared to HD (P<0.05). HPLC results showed that compared with the scramble group, the intracellular and medium supernatant content of ARP1 cells and the medium supernatant of OCI-MY5 in the VARS-shRNA group was increased (all P<0.05).@*CONCLUSIONS@#MM patients with abnormal high expression of VARS have a poor prognosis. VARS promotes the malignant growth of MM cells by affecting the regulation of valine metabolism.
Subject(s)
Humans , Valine-tRNA Ligase , Multiple Myeloma/genetics , Metabolomics , Amino Acids , RNA, TransferABSTRACT
ABSTRACT Objective To assess the relationship between branched-chain amino acids intake in the current diet and the metabolic and body adiposity markers in a population at cardiovascular risk. Methods This is a cross-sectional study with 282 adults and elderly people from the Cardiovascular Health Care Program of the Universidade Federal de Viçosa. Sociodemographic, anthropometric and body composition data, as well as metabolic biomarkers were collected using standardized protocols. Dietary intake of branched amino acids was assessed using a 24-hour recall. Results Individuals with a higher branched-chain amino acids intake (≥2.6g/day, median value) had lower body fat (29.6 vs 32.2%; p=0.019), and higher serum ferritin (113.2 vs. 60.1mg/dL; p=0.006) and uric acid concentrations (4.4 vs. 4.0; p=0.023). In addition, a lower prevalence of overweight and excessive abdominal fat (p<0.05) was found in the individuals with higher branched-chain amino acids intake. They also had a higher daily intake of fiber, copper, zinc, magnesium, and iron, as well as a lower intake of total lipids. Conclusion In the present study, the intake of branched amino acids is negatively related to total and central adiposity, but more studies are needed to fully elucidate this possible relationship. (Brazilian Registry of Clinical Trials, code RBR-5n4y2g).
RESUMO Objetivo Avaliar a relação entre o consumo de aminoácidos de cadeia ramificada na dieta atual e os marcadores de adiposidade metabólica e corporal em uma população com perfil de elevado risco cardiovascular. Métodos Trata-se de um estudo transversal com 282 adultos e idosos do Programa de Atenção Cardiovascular da Universidade Federal de Viçosa. Dados sociodemográficos, antropométricos e de composição corporal, além de biomarcadores metabólicos, foram coletados utilizando protocolos padronizados. O consumo alimentar de aminoácidos ramificados foi avaliado através de um recordatório de 24 horas. Resultados Indivíduos com maior consumo de aminoácidos de cadeia ramificada (≥2,6g/dia, valor da mediana) apresentaram menores valores de gordura corporal (29,6 vs 32,2%; p=0,019) e maiores valores de séricos de ferritina (113,2 vs. 60,1mg/dL; p=0,006) e ácido úrico (4,4 vs. 4,0; p=0,023). Além disso, foi encontrada uma menor prevalência de sobrepeso e excesso de gordura abdominal (p<0,05) nos indivíduos com maior consumo de aminoácidos de cadeia ramificada. Eles também apresentaram um maior consumo diário de fibra, cobre, zinco, magnésio e ferro, além de um menor consumo de lipídios totais. Conclusão No presente estudo, o consumo de aminoácidos ramificados está negativamente relacionado à adiposidade total e central, porém mais estudos são necessários para elucidar completamente essa possível relação. (Registro Brasileiro de Ensaios Clínicos, código RBR-5n4y2g)
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Valine , Adiposity , Amino Acids, Branched-Chain , Isoleucine , Leucine , Heart Disease Risk FactorsABSTRACT
ABSTRACT Introduction: Fatigue due to endurance exercise results from both peripheral and central changes, and may influence subsequent performance during a strength task. The increase in serotonin concentration is one of the central factors associated with endurance exercise-induced fatigue, particularly in hot environments. A nutritional strategy employed to reduce serotonergic activation is supplementation with branched-chain amino acids (BCAA). Objective: To investigate whether BCAA supplementation attenuates the reduction in isometric force caused by prior endurance exercise in a hot environment. Methods: Nine volunteers (aged 25.4 ± 1.2 years) performed a 2-min maximal voluntary isometric contraction (MVCISO) of upper limb muscles before and after an endurance exercise on a cycle ergometer at 40% of the maximal aerobic power. The volunteers underwent three experimental trials: 1) endurance exercise in a temperate environment (23°C and 60% RH); exercise in a hot environment (35°C and 60% RH) with the ingestion of: 2) a placebo solution or 3) a solution containing BCAA 30 mg.kg−1. During the MVCISO test, the isometric force of flexor muscles of the right elbow, core body temperature (TCORE) and heart rate (HR) were measured. Results: Isometric force decreased following endurance exercise in the hot environment, and BCAA administration did not attenuate this reduction. Greater TCORE and HR values were observed following endurance exercise in the heat, compared to pre-exercise values, and supplementation did not interfere with these physiological responses. Conclusion: The reduction in isometric force, caused by previous endurance exercise in a hot environment, was not diminished by supplementation with BCAA. Level of evidence I; Type of study: Therapeutic studies - Investigation of treatment outcomes.
RESUMO Introdução: A fadiga decorrente de um exercício de endurance ocorre devido a alterações tanto periféricas quanto centrais e pode influenciar no desempenho subsequente durante um teste de força. Sabe-se que o aumento da concentração de serotonina é um dos fatores centrais associados à fadiga induzida pelo exercício de endurance, principalmente em ambientes quentes. Uma estratégia nutricional utilizada para diminuir a ativação serotonérgica é a suplementação com aminoácidos de cadeia ramificada (AACR). Objetivo: Investigar se a suplementação com AACR atenua a redução da força isométrica causada pela realização prévia de um exercício de endurance em ambiente quente. Métodos: Nove voluntários (25,4±1,2 anos) realizaram uma contração voluntária máxima isométrica (CVMISO) de membro superior durante 2 min, antes e após um exercício de endurance em um cicloergômetro a 40% da potência máxima aeróbica. Os voluntários foram submetidos a três situações experimentais: 1) exercício de endurance em ambiente temperado (23°C e 60% URA); exercício em ambiente quente (35°C; 60% URA) com ingestão de: 2) solução placebo ou 3) solução contendo 30 mg.kg−1 de AACR. Durante o teste de CVMISO, a força isométrica dos músculos flexores do cotovelo direito, a temperatura corporal interna (TINT) e a frequência cardíaca (FC) foram medidas. Resultados: A força isométrica diminuiu após o exercício de endurance no ambiente quente e a administração de AACR não atenuou essa redução. Valores maiores de TINT e FC foram observados após o exercício de endurance em ambiente quente em relação aos valores do pré-exercício, sendo que a suplementação também não interferiu nessas respostas fisiológicas. Conclusão: A redução da força isométrica, devido à realização prévia de exercício de endurance em ambiente quente, não foi atenuada pela suplementação com AACR. Nível de evidência I; Tipo de estudo: Estudos terapêuticos - Investigação dos resultados do tratamento.
RESUMEN Introducción: La fatiga derivada de un ejercicio de endurance ocurre debido a las alteraciones tanto periféricas como centrales y puede influir en el desempeño subsiguiente durante un test de fuerza. Se sabe que el aumento de la concentración de serotonina es uno de los factores centrales asociados a la fatiga inducida por el ejercicio de endurance, principalmente en ambientes cálidos. Una estrategia nutricional empleada para disminuir la activación serotonérgica es la suplementación con aminoácidos de cadena ramificada (AACR). Objetivo: Investigar si la suplementación con AACR atenúa la reducción de la fuerza isométrica causada por la realización previa de un ejercicio de endurance en ambiente cálido. Métodos: Nueve voluntarios (25,4 + 1,2 años) realizaron una contracción voluntaria máxima isométrica (CVMISO) de dos minutos de miembro superior, antes y después de un ejercicio de endurance en un cicloergómetro a 40% de la potencia máxima aeróbica. Los voluntarios fueron sometidos a tres situaciones experimentales: 1) ejercicio de endurance en ambiente templado (23° C y 60% HR); ejercicio en ambiente cálido (35° C, 60% HR) con ingestión de: 2) solución placebo o 3) solución conteniendo 30 mg.kg−1 de AACR. Durante el test de CVMISO, se midieron la fuerza isométrica de los músculos flexores del codo derecho, la temperatura corporal interna (TINT) y la frecuencia cardíaca (FC). Resultados: La fuerza isométrica disminuyó después del ejercicio de endurance en el ambiente cálido y la administración de AACR no atenuó esa reducción. Se observaron mayores valores de TINT y FC después del ejercicio de endurance en ambiente cálido con relación a los valores del pre ejercicio, siendo que la suplementación tampoco interfirió en estas respuestas fisiológicas. Conclusión: La reducción de la fuerza isométrica, debido a la realización previa de ejercicio de endurance en ambiente cálido, no fue atenuada por la suplementación con AACR. Nivel de evidencia I; Tipo de estudio: Estudios terapéuticos - Investigación de los resultados del tratamiento.
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ABSTRACT Alongside a proper diet, ergogenic aids with potential direct and/or indirect physical performance enhancing effects are sought after for improved adaptation to physical training. Nutritional ergogenics include diet composition changes and/or dietary supplementation. Branched-chain amino acids valine, leucine and isoleucine are widely popular among products with ergogenic claims. Their major marketing appeal derives from allegations that branched-chain amino acids intake combined with resistance physical exercise stimulates muscle protein synthesis. Evidence supporting the efficacy of branched-chain amino acids alone for muscle hypertrophy in humans is somewhat equivocal. This brief review describes physiological and biochemical mechanisms underpinning the effects of complete protein source and branched-chain amino acid intake on skeletal muscle growth in the postabsorptive and post-exercise state. Evidence in favor of or against potential anabolic effects of isolated branched-chain amino acid intake on muscle protein synthesis in humans is also examined.
RESUMO No treinamento físico, buscam-se, além de uma dieta adequada, recursos ergogênicos que possam maximizar direta e/ou indiretamente o desempenho físico. Entre as categorias de recursos ergogênicos, o nutricional compreende a modulação da composição dietética e/ou uso de suplementação. A comercialização dos suplementos de aminoácidos de cadeia ramificada valina, leucina e isoleucina possui muita popularidade entre aqueles com alegação ergogênica. O principal marketing está na afirmação de que o consumo isolado de aminoácidos de cadeia ramificada associado ao exercício físico resistido estimula a síntese de proteína muscular. As evidências da eficácia da ingestão isolada de aminoácidos de cadeia ramificada para a hipertrofia muscular em humanos parecem equivocadas. Nesta breve revisão, apresentamos a compreensão fisiológica e bioquímica de como a ingestão de uma fonte completa de proteína e de aminoácidos de cadeia ramificada afeta o crescimento do músculo esquelético no estado pós-absortivo e pós-exercício. Mostramos também as evidências que suportam ou não a afirmação dos potenciais efeitos anabólicos na síntese de proteína muscular dos aminoácidos de cadeia ramificada quando consumidos isoladamente em humanos.
Subject(s)
Humans , Amino Acids, Branched-Chain/metabolism , Muscle Proteins/biosynthesis , Exercise/physiology , Muscle, Skeletal/metabolism , Postprandial Period/drug effects , Dietary Supplements , Gastrointestinal Absorption/drug effects , Amino Acids, Branched-Chain/physiologyABSTRACT
The Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen for mattrygghet, VKM) has, at the request of the Norwegian Food Safety Authority (Mattilsynet; NFSA), assessed the risk of "other substances" in food supplements and energy drinks sold in Norway. VKM has assessed the risk of doses given by NFSA. The risk assessments are the scientific basis for NFSA in its efforts to regulate the use of "other substances" to food supplements. "Other substances" are described in the food supplement directive 2002/46/EC as substances other than vitamins or minerals that have a nutritional and/or physiological effect. It is added mainly to food supplements, but also to energy drinks and other foods. VKM has not in this series of risk assessments of "other substances" evaluated any claimed beneficial effects from these substances, only possible adverse effects. The present report is a risk assessment of L-leucine, L-isoleucine and L-valine and it is based on previous risk assessments and articles retrieved from a literature search. In this report Lleucine, L-isoleucine and L-valine may occasionally be termed merely leucine, isoleucine or valine. L-leucine, L-isoleucine and L-valine are essential amino acids. L-leucine, L-isoleucine and Lvaline are commonly known as Branched Chain Amino Acids (BCAAs), and are found in food items containing proteins and in particular, in protein-rich foods such as dairy products, meats, eggs, nuts, whole grains, seeds, avocadoes and edible seaweed. According to information from NFSA, L-leucine, L-isoleucine and L-valine are ingredients in food supplements sold in Norway. NFSA has requested a risk assessment of the following doses of L-leucine, L-isoleucine and L-valine in food supplements for adults, adolescents and children 10 years and above: L-leucine: 2500, 3000, 4000, 5000 and 5250 mg/day, Lisoleucine: 1500, 1750, 2000 and 2500 mg/day and L-valine: 1500, 1750, 2000, 2250 and 2500 mg/day. Usual dietary intakes of these amino acids in Norway are not known. Based on data from the 1988–1994 NHANES III, mean daily intakes in adults of leucine, isoleucine and valine from food and supplements are 6.1, 3.6 and 4.0 g/day, respectively (IOM, 2005). Most studies on BCAAs have focused on the three amino acids taken as single amino acids or together combined in food supplements. It has been shown that BCAAs are not metabolized in the liver as is common for most other amino acids but taken up by most peripheral tissues (in particular muscle) where they are either used in protein synthesis or as precursors for nitrogen and/or a number of carbon containing molecules. There is a lack of relevant well-designed supplementation studies with L-leucine, L-isoleucine and L-valine in humans designed to address adverse effects and dose-response relationships as primary outcome. However, daily doses of as much as 30 g BCAA per day given to athletes have been investigated and reported to improve performance. In these reports adverse effects were not addressed and not reported. L-leucine has been administered orally in single doses for one day of up to 50 g without showing any adverse effects. There are no published studies on the effects of longitudinal supplementation with either L-isoleucine or L-valine. Thus, there are no published studies that can be used for suggesting a "value for comparison", and there is no scientific data in the literature suitable for assessing the specific doses in the terms of reference. WHO (2007) recommendations for BCAAs are: Leucine 2730 mg/day, isoleucine 1400 mg/day and valine 1820 mg/day. For a 70 kg person, this corresponds to 39 mg leucine/kg body weight (bw) per day, 20 mg isoleucine/kg bw per day and 26 mg valine/kg bw per day. The acute upper tolerable metabolic limit of L-leucine for men between 20 and 35 years was determined by administration of single doses of 550-700 mg/kg bw over one day. This corresponded to 39 to 50 g/day for a person of 70 kg. Furthermore, based on several studies investigating L-leucine, L-isoleucine and L-valine supplemented as single doses ranging from 10 to 30 g/day without any reported adverse effects. The uncertainties for this consideration are described in chapter 5. VKM concludes that: Due to lack of studies addressing adverse effects for the specified doses 2500, 3000, 4000, 5000 and 5250 mg/day L-leucine, 1500, 1750, 2000 and 2500 mg/day L-isoleucine and 1500, 1750, 2000, 2250 and 2500 mg/day L-valine in food supplements, no conclusions can be made for adults (≥ 18 years), adolescents (≥ 10 and < 18 years) or children (< 10 years).
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@#Introduction: Branched-chain organic acidurias include maple syrup urine disease (MSUD), isovaleric acidemia (IVA), propionic acidemia (PA), and methylmalonic acidemia (MMA). Long term management requires diets of adequate energy and protein with restriction of the offending amino acids. Standard commercial formulas are expensive and unaffordable to patients of low socio-economic status. Methods: This study aimed to develop food products for branched-chain organic acidurias children aged 4-15 years using locally available raw materials in Thailand. Fish maw (Pangasius hypophthalmus) and roasted sunflower kernel (Helianthus annuus) were selected as protein sources due to their low leucine contents. Five formulations were developed, namely (i) powder (low leucine, isoleucine, and valine for MSUD) for tube feeding preparation, (ii) – (v) rice sprinkle powder, bouillon cube, instant cocoa drink, and snack bar, respectively with low leucine for IVA; low valine, isoleucine, methionine and threonine for PA and MMA. Results: All five formulated products provide 500-600 kcal/100 g, adequate protein in which the offending amino acids were controlled at non-harmful levels. These products were shelf stable at room temperature (Aw = 0.3-0.5). Conclusion: The products that were formulated from fish maw and roasted sunflower kernel provide proteins of appropriate quality and quantity for long-term management of branched-chain organic acidurias. The developed products should be further tested for efficacy among patients in accordance with an adequately powered study design.
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Objective To observe glomerular mesangial cells (GMCs) proliferation induced by IgA1 and the association with the expression of apoptosis-related proteins-B cell lymphoma-2 (Bcl-2),cysteine aspartic acid protease-3 (Caspase-3),cysteine aspartic acid protease-9 (Caspase-9) and with mitofusin 2 (Mfn2) in rat GMCs,to study the possible mechanism of valsartan inhibiting rat GMCs proliferation,and to provide a new direction for the mechanism of GMCs proliferation and intervention research in IgA nephrology (IgAN).Methods GMCs stimulated with IgA1 were cultured in vitro to detect cellproliferation with the cell counting kit-8 cell activity assay (CCK8).GMCs were divided into three groups:CG,TG and VG.The GMCs proliferation level was detected by the CCK8,using real-time PCR to detect Mfn2 expression and Western blotting to detect protein levels of Mfn2,Bcl-2,Caspase-3,and Caspase-9.Results Rat GMCs proliferated significantly after stimulation with IgA1,and IgA1 could obviously stimulate high expression of Bcl-2 in GMCs and down regulate the expression of Mfn2,Caspase-3,and Caspase-9.Valsartan could inhibit the proliferation of GMCs induced by IgA1 significantly,downregulate the expression of Bcl-2,and upregulate the expression of Mfn2,Caspase-3,and Caspase-9.Conclusions These results showed that the mechanism of action of valsartan in the treatment of lgAN is inhibiting the proliferation of GMCs.This mechanism may be associated with the regulation of apoptosis-related proteins,such as Mfn2,Bcl-2,Caspase-3,and Caspase-9.These findings may provide a new direction for the mechanism of GMCs proliferation and intervention research in IgAN.
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Corynebacterium glutamicum is the main industrial strain to produce L-valine by microbial fermentation. In this study, a low L-alanine producing C. glutamicum strain VWB-2 was constructed by knocking out the alanine aminotransferase encoding gene alaT in a high L-valine producing strain VWB-1. Meanwhile, a site-directed mutagenesis (ilvBN₁ (M13)) was done on the regulatory subunit of acetohydroxyacid synthase (ilvBN), a key enzyme in the L-valine synthesis pathway. Furthermore, the overexpression of the genes involved in the biosynthesis of L-valine, the mutated ilvBN₁ (M13), the acetohydroxy acid isomerase coding genes ilvC, the dihydroxy-acid dehydratase coding gene ilvD and branched-chain amino acid aminotransferase coding gene ilvE, could all promote the L-valine production of VWB-1 by strengthening the carbon flow towards L-valine. With the overexpression of the branched chain amino acid transporter coding gene brnFE and its regulator lrp₁, the L-valine producing capability of VWB-1 was further enhanced. The finally obtained engineered strain VWB-2/pEC-XK99E-ilvBN₁ (M13)CE-lrp₁-brnFE could produce 461.4 mmol/L L-valine in a 5 L fermentor with a sugar acid conversion rate of 0.312 g/g glucose.
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Objective: To study the chemical constituents from Leonurus japonicus Injection. Methods: The constituents were purified by macroporus resin, silica gel, Sephadex LH-20, and recrystallization. The structures were identified by spectroscopic methods and spectroscopic analysis. Results: Fifteen compounds were isolated from L. japonicus Injection, including four amino acids and their derivatives such as N-isobutyl valine (1), valine (2), alanine (3), L-pyroglutamic acid methyl ester (4), nine alkaloids: stachydrine (5), choline (6), trigonelline (7), uracil (8), 5-methyluracil (9), 2', 3'-O-isopropylidene uridine (10), 3-hydroxypyridine (11), 5-hydroxyl-2-hydroxymethylpyridine (12), and 2-methyl-3-hydroxypyridine (13); and two furoic acids such as furan-2- carboxylic acid (14) and 5-hydroxymethyl-2-furancarboxyic acid (15). Conclusion: In addition to compounds 5 and 8, the others are isolated from the plants of Leonurus Linn. for the first time. Among them, compound 1 is a natural product. Its NMR data, undoubtedly assigned by 2D-NMR, have been reported for the first time.
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Objective To study the relationship of single nucleotide polymorphism of angiotensin converting enzyme 2 ( ACE2 ) with essential hypertension(EH) and antihypertensive response of valsartan.Methods A total of 120 case EH patients was received valsartan once daily for four weeks.Direct DNA sequencing was performed to detect the signgle nucleotide polymorphisms of ACE2 in 120 EH patients and 60 controls with normal blood pressure.ResultsThe genotyping data indicated that there were significant differences of G allele frequency between male or female EH group and controls( x2 =5.310,4.423,P ＜0.05 ).Treated with valsartan,patients with.G allele were not found to be associated with reduction in blood pressure( P ＞0.05).Conclusions Our data suggest that the ACE2 G8790A signgle nucleotide polymorphisms might be involved in the development of EH.The risk developing hypertension in the people carrying G allele is higher than that in those carrying other allele.Therefore,ACE2 gene might be a sensitive gene associated with EH.
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Objective To compare the clinical effect of valsartan/amlodipine combination or irbesartan/hydrochlorothiazide(HCTZ)combination in very elderly hypertensives.Methods After a 4-week placebo period,94 hypertensives,aged 75-89 years were random given valsartan 160 mg/amlodipine 5 mg or irbesartan 300 mg/HCTZ 12.5 mg for 24 weeks according to a rospective study.After 4 weeks,amlodipine or HCTZ was doubled in non-responders.Patients were checked every 4 weeks.At each visit,sitting,lying and standing blood pressure(BP),systolic BP(SBP)and diastolic BP(DBP)were measured. At the end of placebo period and treatment period,electrolytes and uric acid were evaluated.Results Blood pressure was significantly decreased in both treatment groups,however,there was no statistical significance between two groups.BP changes from lying to standing position were significantly greater in the irbosartan/HCTZ group(-17.2/-9.1 mmHg)than that in the valsartan/amlodipine group(-10.1/-1.9 mmHg,t=2.14,P＜0.05 for SBP and t=3.11,P＜0.01 for DBP vs.irbesartan/HCTZ).Potassium significantly decreased and uric acid significantly increased(-0.4 mmol/L,t = 2.33,P＜ 0.05 and+29.7μ mol/L,t =2.54,P＜0.05 vs.baseline,respectively)only in the irbesartan/HCTZ group.Conclusions Both combinations had similarly effective in reducing clinical BP in very elderly hypertensives.However,valsartan/amlodipine offered some advantage and less pronounced BP orthostatic changes and absence of metabolic adverse effects.
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Objective To observe the effect of Valsartan on a rat model of acute lung injury and the expression of transforming growth factor-β,TGF-β) ,Smad2/3, Smad7. Methods Twenty-four male adult Sprague-Dawley rats were random divided into three groups : The bleomycin (BLM) group, the control group, and the Valsartan group. Each group contained eight rats. The Valsartan group was treated with Valsartan everyday at a dose of 20 mg/kg after a single intratracheal instillation of bleomycin at a dose of 5mg/kg. BLM group was treated with saline instead of Valsartan after an instillation of bleomycin. The control group was treated with saline instead of Valsartan and bleomycin. Each group was killed at the 7th day after instillation. The lung tissues were harvested for H. E. stain, the immunohistochemistry was used to detect the expressions of TGF-β1, Smad2/3 ,and Smad7. Results The degree of alveolitis in the Valsartan group was ameliorated, compared with those in BLM group (P ＜0. 01). The expressions of TGF-β1 and Smad2/3 in lung tissue of the Valsartan group were significantly lower than that of BLM group(P ＜0. 01). The expressions of Smad7 in lung tissue of the Valsartan group were significantly higher than that of BLM group (0.23 ±0. 02 vs0. 36 ±0.03, P ＜0.01). Conclusions Valsartan could alleviate acute lung injury in rats, which probably be due to the expression decrease of TGF-β1 and Smad2/3 and the expression increase of Smad7 in lung tissues.
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Bitespiramycin, a group of 4"-O-acylated spiramycins with 4"-O-isovalerylspiramycins as the major components, was produced by recombinantspiramycin-producing strain Streptomyces spiramyceticus harboring a 4"-O-acyltransferase gene. The experiment was initially performed in synthetic medium with 0.5 g l-1 Valine, Isoleucine or Leucine feeding at 36 h cultivation. When valine was fed, the biological titer of bitespiramycin was 45.3 percent higher than that of the control group, but the relative content of total isovalerylspiramycin components decreased by 22.5 percent. In the case of ilecine, the biological titer of bitespiramycin and the total isovalerylspiramycins alone were 85 percent and 72.1 percent of the control group, respectively. In contrast, the relative content of other acylated spiramycins increased by 54.41 percent. However, leucine feeding increased the relative content of total isovalerylspiramycins by 41.9 percent while the biological titer of bitespiramycin was nearly equal to that of the control group. The improvement effect of leucine on the biosynthesis of isovalerylspiramycins was further confirmed by feeding of 2.0 g l-1 leucine to the culture with complex medium. After batch feeding with a total amount of 2.0 g l-1 leucine to the culture from 70 h to 90 h, the biological titer of bitespiramycin was almost unreduced, and the final relative content of total isovalerylspiramycins increased from 31.1 percent to 46.9 percent.
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Amino Acids/analysis , Amino Acids/biosynthesis , Spiramycin/analysis , Spiramycin/biosynthesis , Leucine/analysis , Leucine/biosynthesis , Protein Biosynthesis , Methods , MethodsABSTRACT
El polímero poli (VPAVG) pertenece a la familia de materiales bioelásticos derivados de la elastina y ha demostrado poseer cualidades óptimas para la formación de sistemas de cesión controlada, así como una biocompatibilidad aceptable en determinados tejidos. Las formulaciones preparadas a partir del biomaterial deben ser estériles, si se pretende administrar por una vía que implique ruptura de barreras biológicas. Por lo anterior, resulta esencial conocer el comportamiento del polímero y sus formulaciones frente al proceso de esterilización empleado. El objetivo de este trabajo fue, por tanto, evaluar la influencia de la radiación gamma como método de esterilización sobre las ca - racterísticas físicas del poli (VPAVG) y de las partículas for - madas con éste. En cuanto al polímero, no se apreciaron diferencias en su apariencia física antes y después de la esterilización. Sin embargo, las partículas obtenidas a partir del poli (VPAVG) y posteriormente esterilizadas experimentaban cambios en su morfología. En cuanto al tamaño de las partículas, se determinó que las obtenidas con polímero esterilizado presentaban cierta tendencia a formar agregados de menor tamaño que los encontrados con el polímero sin esterilizar. Se concluyó que el biomaterial ensayado y las formulaciones eran susceptibles a las radiaciones gamma como método de esterilización final, proponiéndose recurrir a otro tratamiento que garantice su esterilidad final.
The poli polymer (VPAVG) belongs to the family of bioelastic materials derived from elastin, and it has showed the best qualities for the creation of systems of controlled cession, as well as an acceptable biocompatibility in certain tissues. If any preparation made from this biomaterial has to be administered in any way that implies the rupture of biological barriers, the preparation must be sterile. By this means, it is essential to know the behaviour of this polymer and its formulations, facing the sterilization process being used. The objective of this research was learn the influence of gamma radiation as a sterilization method over the physical characteristics of poli (VPAVG) and the particles formed by it. As the polymer, we did not observe any differences in physical appearance before and after sterilization. Particles formed by the polymer (VPAVG) and sterilized after, experimented changes in their morphology. As the size of the particles, we observed that those obtained with the sterilized polymer showed a tendency to form smaller aggregates than those found with the non-sterilized polymer. We concluded that the essayed biomaterial and its formulations were susceptible to gamma radiations as final sterilization method, proposing to use another treatment to guarantee the final sterile condition.
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Humans , Male , Female , Polymers , Valine/radiation effects , Proline/radiation effects , Sterilization/methods , Alanine/radiation effects , Gamma Rays , Glycine/radiation effects , Biocompatible Materials , Public HealthABSTRACT
Objectives The purpose of this study is to observe the effects of valsartan on hepapetic fibrosis. Methods Thirty male Sprague-Dawley rats were randomly divided into three groups: valsartan -prevetive group (A), modle group of hepatic fibrosis (B)and valsar-tan-treating group (C). The model of hepatic fibrosis in rats was induced by intraperitoneai injection of dimethylnitrosamine (DMN) for 4 weeks(2ml/kg everyday, three times a week). Valsartan (10mg/kg everyday) was given together with injection of DMN per intrngastric (Ig) in group A for 8 weeks. After stop injection of DMN, the S valsartan(10mg/kg, everyday)was given per Ig in group C for 4 weeks. After modeling, normal saline were given per Ig everyday in group B. At the end of eighth week, the histomorphylogic structure of the liver was ob-served with light microscope. Immunohistoebemical staining was used to evaluate the expression of a-SMA. Results In group B, there was a large necrotic area and a number of pesudolobes appeared in the liver tissue. In group A, there were normal hepatic cords. In the group C, there was fibrosis interval formation and portal area expansion and fibrotie intervals extending to the lobule. The quantitative analysis of Mas-son staining showed that the collagen quantities in group B was higher than that of other group(P<0.01). The collagen quantities in group A was lower than that of group C(P<0.05). The results of immanohistochemical staining showed that the expression of a-SMA in group B was strong positive, middle positive in group C, and weak positive in group A (P<0.05). Conclusion The valsartan has preventive and treatment effects on hepatic fibrosis in rats of hepatic fibrosis model induced by DMN, and the preventive effect of valsartan is better than its treatment effect. The valsartan can ameliorate the hver cirrhosis by partly suppressing the activation of HSC.
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lsartan could reduce the release of p-selectin.Conclusions Valsartan could relieve myocardial ischemia reperfusion injury of rat, which may be through reducing p-seleetin of plasma.
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Objective To study the effects of keto-valine-calcium and keto-isoleucine-calcium on(human mesangial cells)HMCs. Method HMCs were stimulated by keto-valine-calcium and keto-isoleucine-calcium. The AT1R and TGF-β1 were detected. MTr method was used to measure the proliferation of HMCs, and cell cycle was studied by flow cytometry. Results The expression of AT1R and TGF-β1was increased in the experiment groups compared with negative and DMSO control groups. Cell cycle G1 attest and cell apoptosis were observed in the experiment groups. Conclusions 10mM keto-valine-calcium and keto-isoleueine-calcium have multiple effects on HMCs in vitro, which not only increased the expression of AT1R,but also the expression of TGF-β1.Furthermore,keto-valine-calcium and keto-isoleucine-calcium can induce cell cycle G1 arrest and cell apoptosis.
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Objective To investigate the significance of renal tubular dysfunction in patients with refractoriness nephrotic syndrome(RNS)and the effect of interference treatment of Valsartan (VAL).Methods 79 cases of RNS and 68 healthy controls were recruited into the study. The 79 patients of RNS were divided randomly into the VAL group and the dipyridam group. On the basis of routine therapy, the VAL group was given VAL(80mg/d),and the dipyridam group taken dipyridam (150mg/d)orally for 12 weeks The glomerular tubular function(u-RBP,α1-MG,β2-MG,mAlb,NAG)were detected and the pathologic changes of tubukinterstitium were observed by using the methods of ELISA, biochemistry and scoring of the pathologic damage of tubulointerstitium before and after 12 weeks of VAL treatment in all of the cases. Results Urinary RBP,α1-MG,β2-MG,mAlb and NAG in all patients with RNS was evidently higher than that in healthy controls(P＜0.01).Those had positive correlations with damages of tubulointerstitium(r=0.436,0.626,0.499,0.668,0.657,P＜0.01).The interference outcome displayed that the excretion rates of urinary series of protein after oral use VAL in treatment group were markedly lower, while the control group had no distinct change. Conclusion There were various injury of tubulointerstitium and the disfiguration of renal tubular function in all cases with RNS. Damages of renal tubular function had positive correlation with tubulointemtitium injury and renal globular injury. Interference treatment with ARB in patients with RNS could improve renal tubular function, which is of great significance in delaying the progress of RNS.
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A new technique for single spore isolation was developed for predacious fungi forming constricting rings directly on the spores using Dactylaria brochopaga and Arthrobotrys dactyloides. Constricting rings were induced directly on the spores by transferring the spores in 25 ppm solution of DL-Valine in sterile distilled water. Freshly hatched and thoroughly washed second stage juveniles of Meloidogyne incognita were transferred into cavity blocks containing induced rings for trapping and killing of nematodes. The killed nematodes were surface sterilized with streptomycin and inoculated into petri dishes containing maize meal agar media with 100 ppm streptomycin. The petri dishes were incubated at 29+/-1degrees C for few days which yielded axenic culture of these fungi.