Amino acids have various prominent functions in plants. Besides their usage during protein biosynthesis, they also represent building blocks for several other biosynthesis pathways and play pivotal roles during signal...Amino acids have various prominent functions in plants. Besides their usage during protein biosynthesis, they also represent building blocks for several other biosynthesis pathways and play pivotal roles during signaling processes as well as in plant stress response. In general, pool sizes of the 20 amino acids differ strongly and change dynamically depending on the developmental and physiological state of the plant cell. Besides amino acid biosynthesis, which has already been investigated in great detail, the catabolism of amino acids is of central importance for adjusting their pool sizes but so far has drawn much less attention. The degradation of amino acids can also contribute substantially to the energy state of plant cells under certain physiological conditions, e.g. carbon starvation. In this review, we discuss the biological role of amino acid catabolism and summarize current knowledge on amino acid degradation pathways and their regulation in the context of plant cell physiology.展开更多
It is widely known that branched chain amino acids（BCAA） are not only elementary components for building muscle tissue but also participate in increasing protein synthesis in animals and humans. BCAA（isoleucine, le...It is widely known that branched chain amino acids（BCAA） are not only elementary components for building muscle tissue but also participate in increasing protein synthesis in animals and humans. BCAA（isoleucine, leucine and valine） regulate many key signaling pathways, the most classic of which is the activation of the m TOR signaling pathway. This signaling pathway connects many diverse physiological and metabolic roles. Recent years have witnessed many striking developments in determining the novel functions of BCAA including：（1） Insufficient or excessive levels of BCAA in the diet enhances lipolysis.（2） BCAA, especially isoleucine, play a major role in enhancing glucose consumption and utilization by up-regulating intestinal and muscular glucose transporters.（3）Supplementation of leucine in the diet enhances meat quality in finishing pigs.（4） BCAA are beneficial for mammary health, milk quality and embryo growth.（5） BCAA enhance intestinal development, intestinal amino acid transportation and mucin production.（6） BCAA participate in up-regulating innate and adaptive immune responses.In addition, abnormally elevated BCAA levels in the blood（decreased BCAA catabolism） are a good biomarker for the early detection of obesity, diabetes and other metabolic diseases. This review will provide some insights into these novel metabolic and physiological functions of BCAA.展开更多
Recent years have witnessed the great advantages of reducing dietary crude protein(CP) with free amino acids(AA)supplementation for sustainable swine industry, including saving protein ingredients, reducing nitrogen e...Recent years have witnessed the great advantages of reducing dietary crude protein(CP) with free amino acids(AA)supplementation for sustainable swine industry, including saving protein ingredients, reducing nitrogen excretion, feed costs and the risk of gut disorders without impairing growth performance compared to traditional diets. However, a tendency toward increased fatness is a matter of concern when pigs are fed low-protein(LP) diets. In response, the use of the net energy system and balanced AA for formulation of LP diets has been proposed as a solution. Moreover, the extent to which dietary CP can be reduced is complicated. Meanwhile, the requirements for the first five limiting AA(lysine, threonine, sulfur-containing AA, tryptophan, and valine) that growing-finishing pigs fed LP diets were higher than pigs fed traditional diets, because the need for nitrogen for endogenous synthesis of non-essential AA to support protein synthesis may be increased when dietary CP is lowered. Overall, to address these concerns and give a better understanding of this nutritional strategy, this paper reviews recent advances in the study of LP diets for swine and provides some insights into future research directions.展开更多
To investigate the effects of propofol, midazolam and thiopental sodium on outco mes and amino acid accumulation in focal cerebral ischemia reperfusion in rats Methods Male Sprague Dawley (SD) rats were scheduled ...To investigate the effects of propofol, midazolam and thiopental sodium on outco mes and amino acid accumulation in focal cerebral ischemia reperfusion in rats Methods Male Sprague Dawley (SD) rats were scheduled to undergo 3 hour middle cerebral artery occlusion by intraluminal suture and 24 hour reperfusion Neurologic outcomes were score d on a 0-5 grading scale Infarct volume was shown with triphenyltetrazolium c hloride staining and measured by an image analysis system Concentrations of va rious amino acids (aspartate, glutamate, glycine, taurine, and gama aminobutyri c acid) were measured after 3 hours of reperfusion using high performance liquid chromatography Propofol, midazolam and thiopental sodium were given intraperi toneally at the beginning of reperfusion Results Both propofol and midazolam attenuated neurological deficits and reduced infarct and edema volumes Propofol showed better neurological protection than midazol am while thiopental sodium did not exhibit any protective effect Both propofol and midazolam decreased excitatory amino acids accumulation, while propofol inc reased gama aminobutyric acid accumulation in ischemic areas in reperfusion Conclusion Propofol and midazolam, but not thiopental sodium, may provide protective effect s against reperfusion induced injury in rats subjected to focal cerebral ischemi a This neurological protection may be due to the acceleration of excitatory am ino acids elimination in reperfusion展开更多
To investigate whether the protective effects of puerarine （Pur） against cerebral ischemia is associated with depressing the extracellular levels of amino acid transmitters in brain of rats. Methods Male Sprague-Daw...To investigate whether the protective effects of puerarine （Pur） against cerebral ischemia is associated with depressing the extracellular levels of amino acid transmitters in brain of rats. Methods Male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion （MCAO） for 60 min followed by 24 h reperfusion. Put （50, 100 mg/kg, i.p.） was administered at the onset of MCAO. The infarct rate and edema rate were detected on TTC （2,3,5-triphenyltetrazolium chloride）-stained coronal sections. The extracellular levels of amino acid transmitters were monitored in striatum of rats with ischemic/reperfusion injury using in vivo microdialysis technique. Furthermore, the protective effects of Pur against glutamate-induced neurotoxicity were detected. Glutamate-induced apoptotic and necrotic cells in hippocampus were estimated by flow cytometric analysis of Annexin-V and PI labeling cells. Results Pur （100 mg/kg） significantly decreased infarct size by 31.6% （P〈0.05）, reduced edema volume （P〈0.05）, and improved neurological functions （P〈0.05） following MCAO. In these rats, the ischemia-induced extracellular levels of aspartate （Asp）, glutamate （Glu）, γ-aminobutyric acid （GABA）, and taurine （Tau） were significantly reduced in striatum of vehicle-treated animals by 54.7%, 56.7%, 75.8%, and 68.1% （P〈0.01 and P〈0.05）. Pur reduced the peak values of Glu and Asp more obviously than those of GABA and Tau, and the rate of Glu/GABA during MCAO markedly decreased in Pur-treated MCAO rats, compared with the vehicle-treated MCAO rats. Meanwhile, apoptosis and necrosis induced by Glu in cultured hippocampal neurons were significantly reduced after Pur treatment. Conclusion Acute treatment with Put at the onset of occlusion significantly depresses ischemia-induced efflux of amino acids, especially, excitotoxicity in the striatum, a mechanism underlying the neuroprotective effect on cellular survival.展开更多
Background: The study aimed to determine the apparent total tract digestibility coefficients(ATTDC) of nutrients, the apparent metabolizable energy(AME and AMEn) and the amino acid(AA) apparent ileal digestibility coe...Background: The study aimed to determine the apparent total tract digestibility coefficients(ATTDC) of nutrients, the apparent metabolizable energy(AME and AMEn) and the amino acid(AA) apparent ileal digestibility coefficients(AIDC)of a partially defatted(BSFp) and a highly defatted(BSFh) black soldier fly larvae meal. The experimental diets were: a basal diet and two diets prepared by substituting 250 g/kg(w/w) of the basal diet with BSFp or BSFh, respectively.Results: Significant differences were found between BSFp and BSFh meals for ATTDC of the nutrients: BSFp resulted more digestible than BSFh, except for ATTDC of CP which did not differed between meals, while a statistical trend was observed for ATTDC of DM and EE. The AME and AMEn values were significantly(P < 0.05) different between the two BSF meals, with higher levels for BSFp(16.25 and 14.87 MJ/kg DM, respectively). The AIDC of the AA in BSFp ranged from 0.44 to 0.92, while in BSFh they ranged from 0.45 to 0.99. No significant differences were observed for the AA digestibility(0.77 and 0.80 for BSFp and BSFh, respectively), except for glutamic acid, proline and serine that were more digestible in the BSFh meal(P < 0.05).Conclusions: Defatted BSF meals can be considered as an excellent source of AME and digestible AA for broilers with a better efficient nutrient digestion. These considerations suggested the effective utilization of defatted BSF larvae meal in poultry feed formulation.展开更多
Two new β-hydroxy amino acid-coupled secoiridoids, named serinosecologanin （1） and threoninose- cologanin （2）, were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their uncommon structu...Two new β-hydroxy amino acid-coupled secoiridoids, named serinosecologanin （1） and threoninose- cologanin （2）, were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their uncommon structures including absolute configurations were determined by spectroscopic data analysis, and confirmed by semisynthesis from the co-occurring secologanin （3） and secologanic acid （4）. Compounds 1 and 2 exhibited resistant activity against β-glucosidase from almonds and hesperidinase from Aspergillus niger, they also showed activity against the release of glucuronidase in rat polymorphonuclear leukocytes induced by the platelet-activating factor with inhibition rates of （34.9 ±3.1 ）% and （53.6 ± 2.6）%, respectively.展开更多
After the application of methionine, a progressive and significant increase occurred in five volatile organic sulfur compounds （VOSCs）： methanethiol （MESH）, dimethyl sulfide （DMS）, dime^yl disulfide （DMDS）, d...After the application of methionine, a progressive and significant increase occurred in five volatile organic sulfur compounds （VOSCs）： methanethiol （MESH）, dimethyl sulfide （DMS）, dime^yl disulfide （DMDS）, dimethyl trisulfide （DMTS） and dimethyl tetrasulfide （DMTeS）. Even in the untreated control without a methionine addition, methionine and its catabolites （VOSCs, mainly DMDS） were found in considerable amounts that were high enough to account for the water＇s offensive odor. However, blackening only occurred in two methionine-amended treatments. The VOSCs production was observed to precede black color development, and the reaching of a peak value for total VOSCs was often followed by water blackening. The presence of glucose stimulated the degradation of methionine while postponing the occurrence of the black color and inhibiting the production of VOSCs. In addition, DMDS was found to be the most abundant species produced after the addition of methionine alone, and DMTeS appeared to be the most important compound produced after the addition of methionine＋glucose. These results suggest that methionine acted as an important precursor of the VOSCs in lakes suffering from algea-induced black bloom. The existence of glucose may change the transformation pathway of methionine into VOSCs to form larger molecular weight compounds, such as DMTS and DMTeS.展开更多
Protein is quantitatively the most expensive nutrient in swine diets. Hence it is imperative to understand the physiological roles played by amino acids in growth, development, lactation, reproduction, and health of p...Protein is quantitatively the most expensive nutrient in swine diets. Hence it is imperative to understand the physiological roles played by amino acids in growth, development, lactation, reproduction, and health of pigs to improve their protein nutrition and reduce the costs of pork production. Due to incomplete knowledge of amino acid biochemistry and nutrition, it was traditionally assumed that neonatal, post-weaning, growing-finishing, and gestating pigs could synthesize sufficient amounts of all ＂nutritionally nonessential amino acids＂ （NEAA） to support maximum production performance. Therefore, over the past 50 years, much emphasis has been placed on dietary requirements of nutritionally essential amino acids as building blocks for tissue proteins. However, a large body of literature shows that NEAA, particularly glutamine, glutamate, arginine and proline regulate physiological functions via cell signaling pathways, such as mammalian target of rapamycin, AMP-activated protein kinase, extracellular signal-related kinase, Jun kinase, mitogen-activated protein kinase, and NEAA-derived gaseous molecules （e.g., nitric oxide, carbon monoxide, and hydrogen sulfide）. Available evidence shows that under current feeding programs, only 70% and 55% of dietary amino acids are deposited as tissue proteins in 14-day-old sow-reared piglets and in 30-day-old pigs weaned at 21 days of age, respectively. Therefore, there is an urgent need to understand the robes and dietary requirements of NEAA in swine nutrition. This review highlights the basic biochemistry and physiology of absorption and utilization of amino acids in young pigs to enhance the efficacy of utilization of dietary protein and to minimize excretion of nitrogenous wastes from the body.展开更多
An experiment was carried out to study the transport process of nitrogen （N） assimilation from tea roots by monitoring the dynamic composition of N compounds in xylem sap after 15^N-NO3 and 15^N-NH4 were fed to the ...An experiment was carried out to study the transport process of nitrogen （N） assimilation from tea roots by monitoring the dynamic composition of N compounds in xylem sap after 15^N-NO3 and 15^N-NH4 were fed to the root of tea plants （Camellia sinensis L.）. Results showed that the main amino acids were glutamine, theanine, axginine, asparic acid and glutamic acid, which accounted for 49%, 17%, 8%, 7%, and 4%, respectively, of the total amino acids in the xylem sap. After the tea plants were fed with 15^N-NO3 and 15^N-NH4 for 48 h, the amount of total amino acids in xylem sap significantly increased and those fed with 15^N-NH4 had higher increment than those with 15^N-NOa. Two hours after 15^N- NO3 and 15^N-NH4 were fed, 15N abundance in glutamine, asparagine, glutamic acid, alanine, and arginine were detected and increased quickly over time. This indicated that it took less than 2 h for NO3-N and NH4-N to be absorbed by tea roots, incorporated into the above amino acids and transported to the xylem sap. Rapid increase in 15^N-NO3 in the xylem sap of tea plants fed with 15^N-NO3 indicated that nitrate could be directly transported to the xylem sap. Glutamine, theanine, and alanine were the main amino acids transported in xylem sap of tea plants fed with both 15^N-NO3 and 15^N-NH4.展开更多
Plant growth, productivity, and seed yield depend on the efficient uptake, metabolism, and allocation of nutrients. Nitrogen is an essential macronutrient needed in high amounts. Plants have evolved efficient and sele...Plant growth, productivity, and seed yield depend on the efficient uptake, metabolism, and allocation of nutrients. Nitrogen is an essential macronutrient needed in high amounts. Plants have evolved efficient and selective transport systems for nitrogen uptake and transport within the plant to sustain development, growth, and finally reproduction. This review summarizes current knowledge on membrane proteins involved in transport of amino acids and peptides. A special emphasis was put on their function in planta. We focus on uptake of the organic nitrogen by the root, source-sink partitioning, and import into floral tissues and seeds.展开更多
Seven new 4-hydroxyben l-substituted amino acid derivatives (1-7), together with 11 known compounds, were isolated from an aqueous extract of the rhizomes of Go,arodia data Blume. Their structures were determined by s...Seven new 4-hydroxyben l-substituted amino acid derivatives (1-7), together with 11 known compounds, were isolated from an aqueous extract of the rhizomes of Go,arodia data Blume. Their structures were determined by spectroscopic and chemical methods. Compounds 1-3 are pyroglutamate derivatives containing 4-hydroxybenzyl units at the N atom and 4-7 are the first examples of natural products with the 4-hydroxybenzyl unit linked vici a thioether bond to 2-hydroxy-3mercaptopropanoic acid (4-6) and 2-hydroxy-4-mercaptobutanoic acid (7), which would be biogenetically derived from cysteine and homocysteine, respectively. The structures of 1 and 2 were verified hi synthesis, while the absolute configurations of 4, 5 and 7 were assigned using Mosher 's method based on the MPA determination rule of A5Rs values. The known compound 4-(hydroxymethy0-5-nifrobenzene1,2-diol (8) exhibited activity against Fe2 r--cysteine induced rat liver microsomal lipid peroxidation with 1050 values of 9.99 x 10 6 mon. (C) 2015 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.'s/. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).展开更多
Background: With increasing health awareness among consumers, the demand for healthier, tastier, higher quality and nutritional value pork is increasing. It has been shown that different dietary starch sources can alt...Background: With increasing health awareness among consumers, the demand for healthier, tastier, higher quality and nutritional value pork is increasing. It has been shown that different dietary starch sources can alter the carcass traits and meat quality. However, research on the effects of different starch sources with clear different amylose/amylopectin ratio on the amino acid and fatty acid composition in Longissimus thoracis(L. thoracis) muscle of pigs is limited. This study aimed to investigate the effects of different dietary starch sources on carcass traits, meat quality, muscle amino acid and fatty acid composition, and the mRNA expression levels of genes involved in lipid metabolism and muscle fiber characteristics in finishing pigs. A total of 72 Duroc × Landrace × Large White barrows were randomly allocated to 3 different dietary treatment groups with 8 replicate pens/group and 3 pigs per pen.Tapioca starch(TS), corn starch(CS), and pea starch(PS), with amylose/amylopectin ratio of 0.11, 0.25, and 0.44,respectively, were used as their dietary starch sources for 40 days.Results: Results showed that the PS diet significantly increased(P < 0.05) the final body weight, average daily gain,loin-eye area, and fat-free lean index compared with the TS diet, but significantly decreased(P < 0.05) the feed to gain ratio and backfat thickness. Compared with the TS diet, PS diet also increased(P < 0.05) the pH45 min, marbling scores, the content of intramuscular fat and inosine monophosphate in the L. thoracis, and decreased(P < 0.05) the drip loss and shear force. In addition, compared with the TS diet, PS diet increased(P < 0.05) the proportions of flavor amino acids, DHA, EPA, and n-3 polyunsaturated fatty acid(PUFA) in the L. thoracis compared with TS diet,but decreased(P < 0.05) the ratio of n-6/n-3 PUFA. Furthermore, compared with the TS diet, PS diet also upregulated(P < 0.05) the lipogenic genes(FAS, LPL, SCD, ACCα) and myosin heavy-chain(MyHC)-IIa mRNA expression levels compared with the TS diet, but do展开更多
Interest in mung bean(Vigna radiata L.) as a functional food is growing; however, studies on the nutritional composition of major mung bean cultivars planted in China are limited.Twenty Chinese mung bean cultivars wer...Interest in mung bean(Vigna radiata L.) as a functional food is growing; however, studies on the nutritional composition of major mung bean cultivars planted in China are limited.Twenty Chinese mung bean cultivars were collected and their nutritional compositions including starch, fat, protein, and phytochemicals were analyzed. The cultivars were found to have a high amount of resistant starch, accounting for 16.1%–22.3% of total starch, and balanced amino acid constitutions. Palmitic acid and linoleic acid were the two dominant fatty acids, accounting for respectively 32.4% and 36.1% of all of the assayed fatty acids. Four bound phenolic acids(syringic, caffeic, p-coumaric, and ferulic acids) and two free phenolic acids(caffeic and ferulic acids) were identified by HPLC. The antioxidant activity of 70%ethanol extracts from the 20 mung bean cultivars was evaluated. Their DPPH and ABTS+free-radical-scavenging capacity ranged from 28.13 ± 2.24 to 35.68 ± 0.71 μmol g-1and from3.82 ± 0.25 to 13.44 ± 1.76 μmol g-1, respectively. Significant positive correlations of ABTS+free-radical-scavenging capacity with total phenolic acids and total flavonoid contents were observed. These results suggest that Chinese mung bean cultivars are rich in balanced nutrients and that their phytochemicals should be considered as potential sources of natural antioxidants.展开更多
Branched chain amino acids(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 ...Branched chain amino acids(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.In patients with advanced chronic liver disease,BCAA concentrations are low,whereas the concentrations of aromatic amino acids such as phenylalanine and tyrosine are high,conditions that may be closely associated with hepatic encephalopathy and the prognosis of these patients.Based on these basic observations,patients with advanced chronic liver disease have been treated clinically with BCAA-rich medicines,with positive effects.展开更多
文摘Amino acids have various prominent functions in plants. Besides their usage during protein biosynthesis, they also represent building blocks for several other biosynthesis pathways and play pivotal roles during signaling processes as well as in plant stress response. In general, pool sizes of the 20 amino acids differ strongly and change dynamically depending on the developmental and physiological state of the plant cell. Besides amino acid biosynthesis, which has already been investigated in great detail, the catabolism of amino acids is of central importance for adjusting their pool sizes but so far has drawn much less attention. The degradation of amino acids can also contribute substantially to the energy state of plant cells under certain physiological conditions, e.g. carbon starvation. In this review, we discuss the biological role of amino acid catabolism and summarize current knowledge on amino acid degradation pathways and their regulation in the context of plant cell physiology.
基金supported by the National Key Basic Research Program(S.Y.Q.,Grant Number 2012CB124704)
文摘It is widely known that branched chain amino acids（BCAA） are not only elementary components for building muscle tissue but also participate in increasing protein synthesis in animals and humans. BCAA（isoleucine, leucine and valine） regulate many key signaling pathways, the most classic of which is the activation of the m TOR signaling pathway. This signaling pathway connects many diverse physiological and metabolic roles. Recent years have witnessed many striking developments in determining the novel functions of BCAA including：（1） Insufficient or excessive levels of BCAA in the diet enhances lipolysis.（2） BCAA, especially isoleucine, play a major role in enhancing glucose consumption and utilization by up-regulating intestinal and muscular glucose transporters.（3）Supplementation of leucine in the diet enhances meat quality in finishing pigs.（4） BCAA are beneficial for mammary health, milk quality and embryo growth.（5） BCAA enhance intestinal development, intestinal amino acid transportation and mucin production.（6） BCAA participate in up-regulating innate and adaptive immune responses.In addition, abnormally elevated BCAA levels in the blood（decreased BCAA catabolism） are a good biomarker for the early detection of obesity, diabetes and other metabolic diseases. This review will provide some insights into these novel metabolic and physiological functions of BCAA.
基金financially supported by the Beijing Swine Innovation Team of Modern Agriculture Industry Technological SystemBeijing Advanced Innovation Center for Food Nutrition and Human Health,College of China Agricultural University
文摘Recent years have witnessed the great advantages of reducing dietary crude protein(CP) with free amino acids(AA)supplementation for sustainable swine industry, including saving protein ingredients, reducing nitrogen excretion, feed costs and the risk of gut disorders without impairing growth performance compared to traditional diets. However, a tendency toward increased fatness is a matter of concern when pigs are fed low-protein(LP) diets. In response, the use of the net energy system and balanced AA for formulation of LP diets has been proposed as a solution. Moreover, the extent to which dietary CP can be reduced is complicated. Meanwhile, the requirements for the first five limiting AA(lysine, threonine, sulfur-containing AA, tryptophan, and valine) that growing-finishing pigs fed LP diets were higher than pigs fed traditional diets, because the need for nitrogen for endogenous synthesis of non-essential AA to support protein synthesis may be increased when dietary CP is lowered. Overall, to address these concerns and give a better understanding of this nutritional strategy, this paper reviews recent advances in the study of LP diets for swine and provides some insights into future research directions.
文摘To investigate the effects of propofol, midazolam and thiopental sodium on outco mes and amino acid accumulation in focal cerebral ischemia reperfusion in rats Methods Male Sprague Dawley (SD) rats were scheduled to undergo 3 hour middle cerebral artery occlusion by intraluminal suture and 24 hour reperfusion Neurologic outcomes were score d on a 0-5 grading scale Infarct volume was shown with triphenyltetrazolium c hloride staining and measured by an image analysis system Concentrations of va rious amino acids (aspartate, glutamate, glycine, taurine, and gama aminobutyri c acid) were measured after 3 hours of reperfusion using high performance liquid chromatography Propofol, midazolam and thiopental sodium were given intraperi toneally at the beginning of reperfusion Results Both propofol and midazolam attenuated neurological deficits and reduced infarct and edema volumes Propofol showed better neurological protection than midazol am while thiopental sodium did not exhibit any protective effect Both propofol and midazolam decreased excitatory amino acids accumulation, while propofol inc reased gama aminobutyric acid accumulation in ischemic areas in reperfusion Conclusion Propofol and midazolam, but not thiopental sodium, may provide protective effect s against reperfusion induced injury in rats subjected to focal cerebral ischemi a This neurological protection may be due to the acceleration of excitatory am ino acids elimination in reperfusion
基金This study was supported by the Natural Science Foundation of Zhejiang Province (No. M303042)the Key Laboratory for Biomedical Engineering of Ministry of Education of China.
文摘To investigate whether the protective effects of puerarine （Pur） against cerebral ischemia is associated with depressing the extracellular levels of amino acid transmitters in brain of rats. Methods Male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion （MCAO） for 60 min followed by 24 h reperfusion. Put （50, 100 mg/kg, i.p.） was administered at the onset of MCAO. The infarct rate and edema rate were detected on TTC （2,3,5-triphenyltetrazolium chloride）-stained coronal sections. The extracellular levels of amino acid transmitters were monitored in striatum of rats with ischemic/reperfusion injury using in vivo microdialysis technique. Furthermore, the protective effects of Pur against glutamate-induced neurotoxicity were detected. Glutamate-induced apoptotic and necrotic cells in hippocampus were estimated by flow cytometric analysis of Annexin-V and PI labeling cells. Results Pur （100 mg/kg） significantly decreased infarct size by 31.6% （P〈0.05）, reduced edema volume （P〈0.05）, and improved neurological functions （P〈0.05） following MCAO. In these rats, the ischemia-induced extracellular levels of aspartate （Asp）, glutamate （Glu）, γ-aminobutyric acid （GABA）, and taurine （Tau） were significantly reduced in striatum of vehicle-treated animals by 54.7%, 56.7%, 75.8%, and 68.1% （P〈0.01 and P〈0.05）. Pur reduced the peak values of Glu and Asp more obviously than those of GABA and Tau, and the rate of Glu/GABA during MCAO markedly decreased in Pur-treated MCAO rats, compared with the vehicle-treated MCAO rats. Meanwhile, apoptosis and necrosis induced by Glu in cultured hippocampal neurons were significantly reduced after Pur treatment. Conclusion Acute treatment with Put at the onset of occlusion significantly depresses ischemia-induced efflux of amino acids, especially, excitotoxicity in the striatum, a mechanism underlying the neuroprotective effect on cellular survival.
基金supported by the University of Turin(Ex 60% 2014–2015)
文摘Background: The study aimed to determine the apparent total tract digestibility coefficients(ATTDC) of nutrients, the apparent metabolizable energy(AME and AMEn) and the amino acid(AA) apparent ileal digestibility coefficients(AIDC)of a partially defatted(BSFp) and a highly defatted(BSFh) black soldier fly larvae meal. The experimental diets were: a basal diet and two diets prepared by substituting 250 g/kg(w/w) of the basal diet with BSFp or BSFh, respectively.Results: Significant differences were found between BSFp and BSFh meals for ATTDC of the nutrients: BSFp resulted more digestible than BSFh, except for ATTDC of CP which did not differed between meals, while a statistical trend was observed for ATTDC of DM and EE. The AME and AMEn values were significantly(P < 0.05) different between the two BSF meals, with higher levels for BSFp(16.25 and 14.87 MJ/kg DM, respectively). The AIDC of the AA in BSFp ranged from 0.44 to 0.92, while in BSFh they ranged from 0.45 to 0.99. No significant differences were observed for the AA digestibility(0.77 and 0.80 for BSFp and BSFh, respectively), except for glutamic acid, proline and serine that were more digestible in the BSFh meal(P < 0.05).Conclusions: Defatted BSF meals can be considered as an excellent source of AME and digestible AA for broilers with a better efficient nutrient digestion. These considerations suggested the effective utilization of defatted BSF larvae meal in poultry feed formulation.
基金Financial support from the National Natural Science Foundation of China (NNSFC Nos.20772156 and 30825044)+1 种基金the Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT,No.IRT1007)the National Science and Technology Project of China (Nos.2012ZX09301002-002 and 2011ZX0 9307002-01)
文摘Two new β-hydroxy amino acid-coupled secoiridoids, named serinosecologanin （1） and threoninose- cologanin （2）, were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their uncommon structures including absolute configurations were determined by spectroscopic data analysis, and confirmed by semisynthesis from the co-occurring secologanin （3） and secologanic acid （4）. Compounds 1 and 2 exhibited resistant activity against β-glucosidase from almonds and hesperidinase from Aspergillus niger, they also showed activity against the release of glucuronidase in rat polymorphonuclear leukocytes induced by the platelet-activating factor with inhibition rates of （34.9 ±3.1 ）% and （53.6 ± 2.6）%, respectively.
基金supported by the National Natural Science Foundation of China (No. 50979102, 40730528,40901252, 20907057)
文摘After the application of methionine, a progressive and significant increase occurred in five volatile organic sulfur compounds （VOSCs）： methanethiol （MESH）, dimethyl sulfide （DMS）, dime^yl disulfide （DMDS）, dimethyl trisulfide （DMTS） and dimethyl tetrasulfide （DMTeS）. Even in the untreated control without a methionine addition, methionine and its catabolites （VOSCs, mainly DMDS） were found in considerable amounts that were high enough to account for the water＇s offensive odor. However, blackening only occurred in two methionine-amended treatments. The VOSCs production was observed to precede black color development, and the reaching of a peak value for total VOSCs was often followed by water blackening. The presence of glucose stimulated the degradation of methionine while postponing the occurrence of the black color and inhibiting the production of VOSCs. In addition, DMDS was found to be the most abundant species produced after the addition of methionine alone, and DMTeS appeared to be the most important compound produced after the addition of methionine＋glucose. These results suggest that methionine acted as an important precursor of the VOSCs in lakes suffering from algea-induced black bloom. The existence of glucose may change the transformation pathway of methionine into VOSCs to form larger molecular weight compounds, such as DMTS and DMTeS.
基金supported by National Research Initiative Competitive Grants from the Animal Reproduction Program(2008-35203-19120)Animal Growth&Nutrient Utilization Program(2008-35206-18764)of the USDA National Institute of Food and Agriculture+6 种基金AHA(10GRNT4480020)Texas A&M AgriLife Research(H-8200)the National Basic Research Program of China(2013CB127302)the National Natural Science Foundation of China(30810103902,30972156,31172217,31272450,and 31272451)China Postdoctoral Science Foundation(2012T50163)Chinese Universities Scientific Funds(2012RC024)the Thousand-People Talent program at China Agricultural University
文摘Protein is quantitatively the most expensive nutrient in swine diets. Hence it is imperative to understand the physiological roles played by amino acids in growth, development, lactation, reproduction, and health of pigs to improve their protein nutrition and reduce the costs of pork production. Due to incomplete knowledge of amino acid biochemistry and nutrition, it was traditionally assumed that neonatal, post-weaning, growing-finishing, and gestating pigs could synthesize sufficient amounts of all ＂nutritionally nonessential amino acids＂ （NEAA） to support maximum production performance. Therefore, over the past 50 years, much emphasis has been placed on dietary requirements of nutritionally essential amino acids as building blocks for tissue proteins. However, a large body of literature shows that NEAA, particularly glutamine, glutamate, arginine and proline regulate physiological functions via cell signaling pathways, such as mammalian target of rapamycin, AMP-activated protein kinase, extracellular signal-related kinase, Jun kinase, mitogen-activated protein kinase, and NEAA-derived gaseous molecules （e.g., nitric oxide, carbon monoxide, and hydrogen sulfide）. Available evidence shows that under current feeding programs, only 70% and 55% of dietary amino acids are deposited as tissue proteins in 14-day-old sow-reared piglets and in 30-day-old pigs weaned at 21 days of age, respectively. Therefore, there is an urgent need to understand the robes and dietary requirements of NEAA in swine nutrition. This review highlights the basic biochemistry and physiology of absorption and utilization of amino acids in young pigs to enhance the efficacy of utilization of dietary protein and to minimize excretion of nitrogenous wastes from the body.
文摘An experiment was carried out to study the transport process of nitrogen （N） assimilation from tea roots by monitoring the dynamic composition of N compounds in xylem sap after 15^N-NO3 and 15^N-NH4 were fed to the root of tea plants （Camellia sinensis L.）. Results showed that the main amino acids were glutamine, theanine, axginine, asparic acid and glutamic acid, which accounted for 49%, 17%, 8%, 7%, and 4%, respectively, of the total amino acids in the xylem sap. After the tea plants were fed with 15^N-NO3 and 15^N-NH4 for 48 h, the amount of total amino acids in xylem sap significantly increased and those fed with 15^N-NH4 had higher increment than those with 15^N-NOa. Two hours after 15^N- NO3 and 15^N-NH4 were fed, 15N abundance in glutamine, asparagine, glutamic acid, alanine, and arginine were detected and increased quickly over time. This indicated that it took less than 2 h for NO3-N and NH4-N to be absorbed by tea roots, incorporated into the above amino acids and transported to the xylem sap. Rapid increase in 15^N-NO3 in the xylem sap of tea plants fed with 15^N-NO3 indicated that nitrate could be directly transported to the xylem sap. Glutamine, theanine, and alanine were the main amino acids transported in xylem sap of tea plants fed with both 15^N-NO3 and 15^N-NH4.
基金Research in M.T.＇s laboratory was supported by the US National Science Foundation （IOS 0135344 and IOS 0448506） and by the Agricultural and Food Research Initiative Competitive Grant no. 2010-65115-20382 from the USDA National Institute of Food and Agriculture. Work in D.R.＇s laboratory was supported by grants from the Swiss National Science Foundation 3100A0-107507 and 31003A 127340, and EU Marie Curie Research Training Network ＇VaTEP - Vacuolar Transport Equipment for Growth Regulation of Plants＇ （M RTN-CT-2006-035833）. No conflict of interest declared.
文摘Plant growth, productivity, and seed yield depend on the efficient uptake, metabolism, and allocation of nutrients. Nitrogen is an essential macronutrient needed in high amounts. Plants have evolved efficient and selective transport systems for nitrogen uptake and transport within the plant to sustain development, growth, and finally reproduction. This review summarizes current knowledge on membrane proteins involved in transport of amino acids and peptides. A special emphasis was put on their function in planta. We focus on uptake of the organic nitrogen by the root, source-sink partitioning, and import into floral tissues and seeds.
基金the National Natural Science Foundation of China (NNSFC Nos. 30825044 and 20932007)+1 种基金the Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT, No. IRT1007)the National Science and Technology Project of China (Nos. 2012ZX09301002-002 and 2011ZX09307002-01) is acknowledged
文摘Seven new 4-hydroxyben l-substituted amino acid derivatives (1-7), together with 11 known compounds, were isolated from an aqueous extract of the rhizomes of Go,arodia data Blume. Their structures were determined by spectroscopic and chemical methods. Compounds 1-3 are pyroglutamate derivatives containing 4-hydroxybenzyl units at the N atom and 4-7 are the first examples of natural products with the 4-hydroxybenzyl unit linked vici a thioether bond to 2-hydroxy-3mercaptopropanoic acid (4-6) and 2-hydroxy-4-mercaptobutanoic acid (7), which would be biogenetically derived from cysteine and homocysteine, respectively. The structures of 1 and 2 were verified hi synthesis, while the absolute configurations of 4, 5 and 7 were assigned using Mosher 's method based on the MPA determination rule of A5Rs values. The known compound 4-(hydroxymethy0-5-nifrobenzene1,2-diol (8) exhibited activity against Fe2 r--cysteine induced rat liver microsomal lipid peroxidation with 1050 values of 9.99 x 10 6 mon. (C) 2015 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.'s/. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
基金supported by the National Natural Science Foundation of China (31902200)Talent Project of the Guangdong Academy of Agricultural Sciences (201803)+5 种基金Special fund for scientific innovation strategy-construction of high level Academy of Agriculture Science,Recommended Program of Guangdong (2018kczx06)Guangdong Modern Agro-industry Technology Research System (2019KJ115)National Key Research and Development Program of China (2016YFD0501210)Science and Technology planning project of Guangdong Province (2019A050505007)key project of Guangzhou Science and Technology Plan (201707020007)Science and Technology planning project of Guangdong Province (2019A050505007)。
文摘Background: With increasing health awareness among consumers, the demand for healthier, tastier, higher quality and nutritional value pork is increasing. It has been shown that different dietary starch sources can alter the carcass traits and meat quality. However, research on the effects of different starch sources with clear different amylose/amylopectin ratio on the amino acid and fatty acid composition in Longissimus thoracis(L. thoracis) muscle of pigs is limited. This study aimed to investigate the effects of different dietary starch sources on carcass traits, meat quality, muscle amino acid and fatty acid composition, and the mRNA expression levels of genes involved in lipid metabolism and muscle fiber characteristics in finishing pigs. A total of 72 Duroc × Landrace × Large White barrows were randomly allocated to 3 different dietary treatment groups with 8 replicate pens/group and 3 pigs per pen.Tapioca starch(TS), corn starch(CS), and pea starch(PS), with amylose/amylopectin ratio of 0.11, 0.25, and 0.44,respectively, were used as their dietary starch sources for 40 days.Results: Results showed that the PS diet significantly increased(P < 0.05) the final body weight, average daily gain,loin-eye area, and fat-free lean index compared with the TS diet, but significantly decreased(P < 0.05) the feed to gain ratio and backfat thickness. Compared with the TS diet, PS diet also increased(P < 0.05) the pH45 min, marbling scores, the content of intramuscular fat and inosine monophosphate in the L. thoracis, and decreased(P < 0.05) the drip loss and shear force. In addition, compared with the TS diet, PS diet increased(P < 0.05) the proportions of flavor amino acids, DHA, EPA, and n-3 polyunsaturated fatty acid(PUFA) in the L. thoracis compared with TS diet,but decreased(P < 0.05) the ratio of n-6/n-3 PUFA. Furthermore, compared with the TS diet, PS diet also upregulated(P < 0.05) the lipogenic genes(FAS, LPL, SCD, ACCα) and myosin heavy-chain(MyHC)-IIa mRNA expression levels compared with the TS diet, but do
基金supported by the earmarked fund for China Agriculture Research System (No. CYTX-014)the Agricultural Science and Technology Innovation Program of CAAS+1 种基金the Program of Science and Technology Cooperation with Hong Kong, Macao, and Taiwan, China (No. 2013DFH30050)the special fund for Agro-scientific Research in the Public Interest (No. 201403063)
文摘Interest in mung bean(Vigna radiata L.) as a functional food is growing; however, studies on the nutritional composition of major mung bean cultivars planted in China are limited.Twenty Chinese mung bean cultivars were collected and their nutritional compositions including starch, fat, protein, and phytochemicals were analyzed. The cultivars were found to have a high amount of resistant starch, accounting for 16.1%–22.3% of total starch, and balanced amino acid constitutions. Palmitic acid and linoleic acid were the two dominant fatty acids, accounting for respectively 32.4% and 36.1% of all of the assayed fatty acids. Four bound phenolic acids(syringic, caffeic, p-coumaric, and ferulic acids) and two free phenolic acids(caffeic and ferulic acids) were identified by HPLC. The antioxidant activity of 70%ethanol extracts from the 20 mung bean cultivars was evaluated. Their DPPH and ABTS+free-radical-scavenging capacity ranged from 28.13 ± 2.24 to 35.68 ± 0.71 μmol g-1and from3.82 ± 0.25 to 13.44 ± 1.76 μmol g-1, respectively. Significant positive correlations of ABTS+free-radical-scavenging capacity with total phenolic acids and total flavonoid contents were observed. These results suggest that Chinese mung bean cultivars are rich in balanced nutrients and that their phytochemicals should be considered as potential sources of natural antioxidants.
文摘Branched chain amino acids(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.In patients with advanced chronic liver disease,BCAA concentrations are low,whereas the concentrations of aromatic amino acids such as phenylalanine and tyrosine are high,conditions that may be closely associated with hepatic encephalopathy and the prognosis of these patients.Based on these basic observations,patients with advanced chronic liver disease have been treated clinically with BCAA-rich medicines,with positive effects.
