BACKGROUND: The purpose of this study was to determine the adequate loading and maintenance doses of N-acetylcyseteine (NAC) for patients suffering from acute ROS-induced injury. METHODS: Concentrations of extra cellular NAC, cysteine (Cys), cystine (Cyst2), and methionine (Met) were measured in vitro, at which more than 50% of the intracellular ROS raised by paraquat were suppressed using Swiss 3T3 fibroblasts. An in vivo pharmacokinetic study followed on a healthy subject to determine the proper loading and maintenance doses of reduced NAC following intravenous administration of 25 mg/kg NAC. RESULTS: In vivo, NAC suppressed ROS in a dose dependant manner. 10 mM of NAC suppressed about 50% of ROS, and was comparable to 10 micro M of Cys and Met and 400 micro M of Cys2. In vitro, the elimination of half-life was achieved at 2.88+/-1.14 h for NAC and at 3.68+/-1.84 h for total NAC. The body clearances were 1.23+/-0.77 L h (-1) kg (-1) and 0.56+/-0.27 L h (-1) kg (-1) and the volumes of distribution were 3.07+/-0.10 L kg (-1) and 3.00+/-0.11 L kg (-1), respectively. The loading and maintenance NAC doses used to reach the target concentration of 10 mM, were 5010 mg. kg (-1) and 2250 mg min (-1) kg (-1), respectively. CONCLUSION: NAC provides an antioxidant effect on ROS produced by paraquat in vivo. However, in vitro, our results showed that the intravenous NAC dose could not be estimated from NAC plasma concentration or its metabolites.
Sulfur/*blood ; Reactive Oxygen Species ; Humans ; Glutathione/blood ; Amino Acids/*blood/chemistry ; Acetylcysteine/*administration & dosage/pharmacokinetics/pharmacology

OBJECTIVES: Recent reports have suggested that patients treated by CAPD have a relatively increased risk of death compared to patients undergoing HD, although the cause of this discrepancy is poorly understood. Protein malnutrition is an important risk factor in ESRD. Also, amino acid concentrations, for which the physiological function differs from that of protein, may be an independent risk factor in ESRD. There is no doubt concerning the prevalence of low amino acid levels in both HD and CAPD patients. But the difference in plasma amino acid levels between these two groups has not been well defined. The purpose of this study is to compare plasma amino acid levels between patients with ESRD on HD and CAPD. METHODS: A cross sectional study of overnight fasting plasma amino acid concentrations was performed on 12 CAPD and 45 HD patients with ESRD, matched by age, sex and body mass index. The levels of individual plasma amino acid and TAA, EAA, NEAA and BCAA were compared for the HD and CAPD groups. In order to measure losses during HD and CAPD, amino acid and protein concentrations were measured from 10 dialysates obtained from 10 HD patients and 12 peritoneal dialysis solutions from 12 CAPD patients. RESULTS: All of the measured amino acid concentrations were found to be lower in the CAPD group compared to the HD group. Furthermore, the levels of TAA (2017.3 +/- 781.1 vs. 903.3 +/- 316.1 mumole/L), EAA(1201.8 +/- 492.6 vs. 567.6 +/- 223.2 mumole/L), NEAA(815.5 +/- 308.6 vs. 335.7 +/- 100.2 mumole/L); and BCAA (315.0 +/- 146.0 vs. 145.2 +/- 65.0 mumole/L), were all lower in the CAPD group than in the HD group. The protein loss was 2.0 +/- 0.2 g/L in the peritoneal dialysate but was not detectable in the hemodialysates. TAA loss over a one week period was about 61.8 +/- 13.0mmole for the HD group and 38.0 +/- 13.0 mmole for the CAPD group. CONCLUSIONS: Our results show that amino acid concentrations are lower in ESRD patients on CAPD than on HD. It seems likely that protein loss in the peritoneal dialysate is a contributing factor to lowered plasma amino acid concentrations in ESRD patients on CAPD than on HD. We believe that the lowered amino acid concentrations observed in CAPD patients may worsen the clinical outcome compared to HD patients.
Adult ; Amino Acids/blood* ; Amino Acids/analysis ; Comparative Study ; Dialysis Solutions/chemistry ; Female ; Human ; Kidney Failure, Chronic/therapy* ; Kidney Failure, Chronic/blood* ; Male ; Middle Age ; Peritoneal Dialysis, Continuous Ambulatory/adverse effects* ; Renal Dialysis*/adverse effects

To establish a metabonomic method based on high performance liquid chromatography-quadrupole-time of flight mass spectrometry (HPLC-Q-TOF/MS), in order to study the changes in serum metabolites of systemic lupus erythematosus (SLE) mice after treatment of Jieduquyuziyin prescription, the pathogenesis of SLE and mechanism of drug action. The orthogonal partial least squares (OPLS) was applied for the pattern recognition of experimental data, finding a significant difference in the control group, the SLE model group, the Jieduquyuziyin prescription-treated group and the prednisone acetate-treated group. According to the OPLS load diagram, 12 differential metabolites, including traumatic acid, PAF, 12 (S)-HEPE, 15(S)-HETrE and Hepoxilin B3 were identified by using accurate mass combined with MS/MS data After treatment with Jieduquyuziyin prescription, the relative contents of PAF, 12 (S)-HETE were close to the level of the control group. According to the analysis on metabolic pathway, SLE could cause significant changes in unsaturated fatty acid and amino acid metabolism pathway, while Jieduquyuziyin prescription has a effect in regulating disorder of unsaturated fatty acid metabolism pathway.
Amino Acids ; blood ; Animals ; Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal ; administration & dosage ; chemistry ; Fatty Acids ; blood ; Female ; Humans ; Lupus Erythematosus, Systemic ; blood ; drug therapy ; Male ; Mass Spectrometry ; Mice ; Serum ; chemistry

BACKGROUND/AIMS: A prospective comparative study was conducted to investigate the efficacy of orally administered branched-chain amino acids (BCAA) in cirrhotic patients. METHODS: Forty-seven patients with liver cirrhosis of viral etiologies, whose hypoalbuminemia could not be corrected with adequate protein intake, were randomly assigned to either the BCAA group (n=31) or the control group (n=16). The selection criteria were ages between 16 and 70 years, patients whose Child-Pugh scores were less than 13 points and who were willing to participate in the study. Most patients (87.1%) belonged to Child-Pugh class B. Patients in the BCAA group received oral supplementation with branched-chain amino acid granules (12 g/day, each packet containing total 4 g of BCAA, i.e. leucine, 1904 mg; valine, 1144 mg; isoleucine, 952 mg) for 12 weeks. Patients had complete blood counts and chemistry at entry and once every month. Serum ferritin and amino acid concentrations in plasma were determined. Anthropometric parameters including body weight, body fat contents and body mass index were assessed at the beginning and at the end of the 3-month period. RESULTS: In the BCAA group, there was a significant increment in plasma levels of isoleucine, valine (p < 0.001) whereas levels of aromatic amino acids did not show substantial change. Total BCAA concentration and BCAA/AAA (aromatic amino acid) molar ratio (Fischer's ratio) also increased significantly after the administration of oral BCAA (p < 0.001). In contrast, patients in the control group showed no significant change in assessed parameters. CONCLUSION: Oral supplementation of BCAA to cirrhotic patients improved several parameters reflecting nutritional status without causing encephalopathy or other serious adverse effects.
Adipose Tissue ; Amino Acids, Aromatic ; Amino Acids, Branched-Chain ; Blood Cell Count ; Body Mass Index ; Body Weight ; Chemistry ; Ferritins ; Humans ; Hypoalbuminemia ; Isoleucine ; Leucine ; Liver Cirrhosis ; Molar ; Nutritional Status* ; Patient Selection ; Plasma ; Prospective Studies* ; Valine

In order to evaluate the effect and mechanism of the mulberry leaf alkaloid, flavones, and polysaccharide intervention on diabetes, the overall metabolite profiling characteristics for the plasma of diabetic mouse was performed by using an ultra-performance liquid chromatography/electrospray-tandem mass spectrometry (UPLC-ESI-MS). The 8 potential biomarkers were found in diabetic mice plasma based on the data of MS/MS characteristics obtained from the UPLC-OrbitrapMS analysis, which mainly involved in sphingolipids, amino acid metabolic pathway. The principal component analysis showed that the normal group and model group were obviously distinguished and implied that metabolic disturbance was happened in diabetic mice plasma. The extracts of mulberry leaf flavonoids, polysaccharide, alkaloid had exhibited the effects of callback function for diabetic mice through regulating the amino acid metabolism and sphingolipid metabolism.
Alkaloids ; chemistry ; Amino Acids ; metabolism ; Animals ; Biomarkers ; blood ; Chromatography, High Pressure Liquid ; Diabetes Mellitus, Experimental ; drug therapy ; Flavones ; chemistry ; Flavonoids ; chemistry ; Metabolic Networks and Pathways ; Metabolomics ; Mice ; Morus ; chemistry ; Plant Leaves ; chemistry ; Sphingolipids ; metabolism ; Tandem Mass Spectrometry

To further explore the mechanism of congenital pyrimidine 5'-nuleotidase I (P5'N-I) deficiency, on the basis of purification of the protein, the molecular weight and amino acid composition were analysed by mass-spectrograph and amino-acid analyzer, microsequencing and bioinformation analysis of P5'N-I were performed after it was hydrolysed by trypsin. The results showed that three fractions were found in the purified P5'N-I and their molecular weights were 26,952.9, 55,476 and 110,938, respectively. The sequence from one of the peptide fragments was I-E-G-P-T-I-R-Q-I-E. The homologous sequence was not found after comparision with the ten-amino-acid sequence in GenBank by blast procedure. Amino acid analysis indicated that P5'N-I was composed of 18 amino acids at least, and 243 amino acid residues. In conclusion, the enzyme might be an allosteric enzyme, there might be homologous dimer or tetramer in physiological status of normal human erythrocyte, the microsequence could be designed as the probe for fishing the genes of interest. The composition of amino acid might be an important information in determination of its protein primary structure.
5'-Nucleotidase ; blood ; chemistry ; isolation & purification ; Amino Acid Sequence ; Amino Acids ; analysis ; Chromatography, High Pressure Liquid ; Electrophoresis, Polyacrylamide Gel ; Erythrocytes ; enzymology ; Humans ; Mass Spectrometry ; Molecular Weight ; Peptide Fragments ; chemistry ; Sequence Analysis, Protein

We examined whether high flux membranes (HF) may induce a greater loss of amino acids compared to low flux membranes (LF). Ten hemodialysis patients participated in this study. Pre- and post-hemodialysis plasma amino acid profiles were measured by reverse-phase high pressure liquid chromatography for both HF and LF. We measured the dialysate amino acid losses during hemodialysis. The reduction difference for plasma total amino acid (TAA), essential amino acid (EAA), and branch chained amino acid (BCAA) was not significantly different in comparisons between the two membranes. (HF vs. LF; TAA 66.85+/-30.56 vs. 53.78+/-41.28, p=0.12; EAA 14.79+/-17.16 vs. 17.97+/-28.69, p=0.12; BCAA 2.21+/-6.08 vs. 4.16+/-10.98 mg/L, p=0.13). For the HF, the reduction in plasma amino acid levels for TAA and EAA were statistically significant. Although it was not statistically significant, the dialysate losses of BCAA were greater than the reduction in plasma (plasma reduction vs. dialysate loss; HF 2.21+/-6.08 vs. 6.58+/-4.32, LF 4.16+/-10.98 vs. 7.96+/-3.25 mg/L). HF with large pores and a sieving coefficient do not influence dialysate amino acid losses. Hemodialysis itself may influence the dialysate amino acid losses and may have an effect on protein metabolism.
Adult ; Aged ; Amino Acids/*blood/chemistry ; Bicarbonates/blood ; Blood Urea Nitrogen ; Chromatography, High Pressure Liquid ; Creatine/blood ; Dialysis Solutions/analysis ; Female ; Humans ; Male ; *Membranes, Artificial ; Middle Aged ; Potassium/blood ; Renal Dialysis/*instrumentation ; Sodium/blood

OBJECTIVEThe pathogenesis of Tourette syndrome (TS) is associated with the disorders of neurotransmitters, such as dopamine (DA) and excitatory amino acids (EAA). Antiepileptic drugs such as topiramate have shown some effects on TS, but the mechanism has not been clearly identified. The objective of the research was to evaluate the relationship between the pathogenesis of TS and abnormality of neurotransmitters by determining the levels of brain free DA and plasma EAA in iminodipropionitrile (IDPN) induced head twitch response (HTR) rats, and to investigate the effects of topiramate on HTR induced by IDPN.

METHODSForty-eight Sprague-Dawley rats were randomly divided into six groups: blank control, TS model, and haloperidol-(0.5 mg/kg) and topiramate-treated (5, 10 and 20 mg/kg). HTR was induced by 7-day peritoneal injections of IDPN (150 mg/kg daily) and was used as TS model. Brain free DA levels and plasma levels of EAA were measured using ELISA and high performance liquid chromatography respectively 35 days after haloperidol or topiramate administration.

RESULTSBrain free DA levels were significantly lower and plasma EAA levels were significantly higher in the TS model group compared with those in the blank control group (P<0.05). Topiramate of 10 and 20 mg/kg significantly decreased the frequency of IDPN-induced HTR and significantly increased the level of brain free DA when compared with the TS model group (P<0.05). Topiramate of 20 mg/kg treatment as haloperidol treatment significantly decreased plasma EAA levels compared with the TS model group (P<0.05).

CONCLUSIONSThe pathogenesis of TS is related to the super-sensitivity of DA receptor in the center nervous system and the over-effect of plasma EAA. Topiramate can reduce IDPN-induced HTR, probably through the inhibition of DA and DA-receptor combination in the brain and the secretion and release of plasma EEA.

Animals ; Anticonvulsants ; therapeutic use ; Behavior, Animal ; drug effects ; Brain Chemistry ; drug effects ; Dopamine ; analysis ; Excitatory Amino Acids ; blood ; Fructose ; analogs & derivatives ; therapeutic use ; Male ; Rats ; Rats, Sprague-Dawley ; Tourette Syndrome ; drug therapy

BACKGROUND AND OBJECTIVES: The basic principle of microdialysis is to mimic the function of a capillary blood vessel by perfusing physiologic liquid implanted into the target tissue. Amino acids are supposed to have functions for controlling the homeostasis of normal nasal mucosa and a role in the pathogenesis of allergic rhinitis. However, no studies have been conducted about the existence of amino acids in the nasal cavity. This study measures the concentration of 19 amino acids found in the nasal cavity of normal control and experimentally allergy-induced animal model in order to evaluate the difference in the concentration of amino acids between normal and allergic nasal mucosa. MATERIALS AND METHOD: An experimentally induced nasal allergy model was developed by intraperitoneal and intranasal sensitization with ovalbumin in Dunkin-Hartely guinea pigs according to a programmed protocol. A microdialysis probe was designed to be suitable to nasal mucosa using a Cuprophan hollow fiber (200 micrometer inner diameter, 300 micrometer outer diameter, 45 kDa molecular weight cut-off, Fitral, AN 69-HF). After verification of the probe, microdialysis was performed in the inferior turbinate submucosa of normal control (N=8) and experimental (N=8) groups. The concentration of 19 amino acids was analyzed using high performance liquid chromatography. Statistical analysis was performed using a student t-test. RESULTS: All 19 amino acids were validated at various concentrations in the nasal cavity. Glutamate (p=0.036) and GABA (p<0.001) concentrations were significantly higher in the experimental group than in the control group. CONCLUSION: The 19 amino acids measured existed in the nasal cavity at various concentrations, and the concentrations of glutamate and GABA were significantly higher in the allergy group than in the control group. The microdialysis technique is a powerful tool not only to measure endogenous substances for target organ chemistry but also to pharmacokinetically evaluate exogenous drug delivery processes in the nasal cavity.
Amino Acids ; Animals ; Blood Vessels ; Capillaries ; Chemistry ; Chromatography, Liquid ; gamma-Aminobutyric Acid ; Glutamic Acid ; Guinea Pigs ; Homeostasis ; Humans ; Hypersensitivity* ; Microdialysis* ; Models, Animal ; Molecular Weight ; Nasal Cavity ; Nasal Mucosa ; Ovalbumin ; Rhinitis ; Turbinates

An alpha-amylase inhibitor (alpha-AI) was isolated from white kidney beans (Phaseolus vulgaris L) by ethanol fractional precipitation, ion exchange chromatography and gel filtration column chromatography. It was a homogeneity glycoprotein demonstrated by SDS-PAGE and gel filtration on CL-6B. The glycoprotein contained 88.2% protein and was rich in aspartic acid, glutamic acid, leucine, threonine and serine. The carbohydrate moiety was consisted of Man, Glc, Gal and Xyl in a mole ratio of 2.42: 1.50: 1.52: 1.00. The glycan and the core protein backbone was connected by O-linkage as determined by beta-elimination reaction. The continuous oral administration of the alpha-AI (150 mg x kg(-1) x d(-1)) for 7 days can lower fasting blood glucose and 300 mg x kg(-1) x d(-1) alpha-AI for 7 days can improve the sugar tolerance on alloxan-dependent diabetic model rats. The result showed the alpha-AI obtained from white kidney beans had good hypoglycemic effect on alloxan induced diabetic rats and may have high potential pharmaceutical value as a regulative digestive-starch degradation in patients suffering from diabetes.
Alloxan ; Amino Acids ; analysis ; Animals ; Blood Glucose ; metabolism ; Diabetes Mellitus, Experimental ; blood ; chemically induced ; Female ; Glycoproteins ; chemistry ; isolation & purification ; pharmacology ; Molecular Weight ; Monosaccharides ; analysis ; Phaseolus ; chemistry ; Plant Lectins ; chemistry ; isolation & purification ; pharmacology ; Plants, Medicinal ; chemistry ; Rats ; Rats, Sprague-Dawley ; Vegetable Proteins ; analysis ; alpha-Amylases ; antagonists & inhibitors