A specific, precise and accurate ion-pair HPLC-UV method has been developed and validated for simultaneous determination of phosphocreatine (PCr), and its metabolite creatine (Cr) as well as related ATP in plasma and ...A specific, precise and accurate ion-pair HPLC-UV method has been developed and validated for simultaneous determination of phosphocreatine (PCr), and its metabolite creatine (Cr) as well as related ATP in plasma and red blood cell (RBC) of rabbits. After addition of TMP as IS, the samples were deproteinized with 6% PCA. The analytes were separated on a Kromasil C18 column using a tertiary gradient mobile phase composed of buffer A (0.2% KH2PO4 + 0.08% tetrabutyl ammonium hydrogen sulphate, pH 3.0), buffer B (buffer A adjusted to pH 7.5 with 1 mol/L NaOH) and MeOH. Detection wavelengths were set at 210 nm for PCr and Cr and 260 nm for ATP and TMP. Some blank samples were initially run for baseline subtraction. The linear detection responses were obtained for PCr concentration over a range of 10 - 7500 mg/ml (plasma) and 5 - 2500 mg/ml (RBC) and for both Cr and ATP concentrations of 10 - 1500 mg/ml (plasma) and 5 - 750 mg/ml (RBC) (r > 0.99). The QC samples of 3 analytes showed intra-day and inter-day precisions (RSD) of - 107%. The method was successfully used to simultaneously determine plasma and RBC concentrations of the 3 analytes and to study pharmacokinetics after iv administration of PCr to rabbits.展开更多
To assess the effects ofcreatine pyruvate (Cr-Pyr) on lipid and protein metabolism in broiler chickens, a total of 400 1-day-old male birds (Aconred) were randomly allocated to four groups, with each group replica...To assess the effects ofcreatine pyruvate (Cr-Pyr) on lipid and protein metabolism in broiler chickens, a total of 400 1-day-old male birds (Aconred) were randomly allocated to four groups, with each group replicating four times and each replicate involving 25 birds. The broilers were provided with a commercial diet supplemented with Cr-Pyr at 0, 1, 5, or 10% of the diet, respectively, for a period of 3 wk ad libitum (from 22 to 42 d). In the present study, body weight (BW) and average daily gain (ADG) of broilers decreased in 10% Cr-Pyr group (P〈0.01), whereas the relative leg and pectoral muscle weights were significantly higher than they were in the control group (P〈0.05). 5 or 10% Cr-Pyr of diets decreased the abdominal fat rate (AFR, abdominal fat/live weight) of the broilers. The serum or hepatic triglyceride (TG) concentrations were significantly lower in the 5 and 10% groups (P〈0.01). In contrast, Cr-Pyr caused a marked increase in the serum nonesterified fatty acid (NEFA), high-density lipoprotein cholesterol (HDL-C) and creatine kinase (CK) concentrations (P〈0.01). Supplementation with Cr-Pyr (5 and 10%) in the diet also increased glucagons (GLU), insulin (INS) or leptin (LEP) contents (P〈0.01). The expression of hepatic peroxisomal proliferators-activated receptor α (PPAR-α) and carnitine palmitoyl transferase-I (CPT-I), muscle insulin-like growth factor I (IGF-I) were significantly elevated and myostatin mRNA level was reduced in the 5 and 10% groups (P〈0.05). It was found that supplementation with 5% Cr-Pyr improves both lipid and protein metabolism by regulating various metabolic parameters of broilers, while not adversely affects growth performance in broiler chickens.展开更多
AIM: To test the hypothesis that fluid resuscitation with Ringer's solution enriched with pyruvate(PR), a physiological antioxidant and energy substrate, affords protection of myocardial metabolism and electrophys...AIM: To test the hypothesis that fluid resuscitation with Ringer's solution enriched with pyruvate(PR), a physiological antioxidant and energy substrate, affords protection of myocardial metabolism and electrophysiological performance superior to lactated Ringer's(LR) during hypovolemia and hindlimb ischemia-reperfusion.METHODS: Male domestic goats(25-30 kg) were exsanguinated to a mean arterial pressure of 48 ± 1 mm Hg. Right hindlimb ischemia was imposed for 90 min by applying a tourniquet and femoral crossclamp. LR or PR, infused iv, delivered 0.05 mmol/kg per minute L-lactate or pyruvate, respectively, from 30 min hindlimb ischemia until 30 min post-ischemia. Time controls(TC) underwent neither hemorrhage, hindlimb ischemia nor resuscitation. Goats were sacrificed and left ventricular myocardium biopsied at 90 min fluid resuscitation(n = 6 per group) or 3.5 h later(n = 9 LR, 10 PR, 8 TC).RESULTS: Myocardial 8-isoprostane content, phosphocreatine phosphorylation potential, creatine kinase activity, and heart rate-adjusted QT interval(QTc) vari- ability were evaluated at 90 min resuscitation and 3.5 h post-resuscitation. PR sharply lowered pro-arrhythmic QTc variability vs LR(P < 0.05); this effect persisted 3.5 h post-resuscitation. PR lowered myocardial 8-isoprostane content, a product of oxidative stress, by 39 and 37% during and 3.5 h after resuscitation, respectively, vs LR. Creatine kinase activity fell 42% post-LR vs TC(P < 0.05), but was stable post-PR(P < 0.02 vs post-LR). PR doubled phosphocreatine phosphorylation potential, a measure of ATP free energy state, vs TC and LR(P < 0.05); this energetic enhancement persisted 3.5 h post-resuscitation.CONCLUSION: By augmenting myocardial energy state and protecting creatine kinase activity, pyruvateenriched resuscitation stabilized cardiac electrical function during central hypovolemia and hindlimb ischemiareperfusion.展开更多
文摘A specific, precise and accurate ion-pair HPLC-UV method has been developed and validated for simultaneous determination of phosphocreatine (PCr), and its metabolite creatine (Cr) as well as related ATP in plasma and red blood cell (RBC) of rabbits. After addition of TMP as IS, the samples were deproteinized with 6% PCA. The analytes were separated on a Kromasil C18 column using a tertiary gradient mobile phase composed of buffer A (0.2% KH2PO4 + 0.08% tetrabutyl ammonium hydrogen sulphate, pH 3.0), buffer B (buffer A adjusted to pH 7.5 with 1 mol/L NaOH) and MeOH. Detection wavelengths were set at 210 nm for PCr and Cr and 260 nm for ATP and TMP. Some blank samples were initially run for baseline subtraction. The linear detection responses were obtained for PCr concentration over a range of 10 - 7500 mg/ml (plasma) and 5 - 2500 mg/ml (RBC) and for both Cr and ATP concentrations of 10 - 1500 mg/ml (plasma) and 5 - 750 mg/ml (RBC) (r > 0.99). The QC samples of 3 analytes showed intra-day and inter-day precisions (RSD) of - 107%. The method was successfully used to simultaneously determine plasma and RBC concentrations of the 3 analytes and to study pharmacokinetics after iv administration of PCr to rabbits.
基金supported by the the National Natural Science Foundation of China (30600439)
文摘To assess the effects ofcreatine pyruvate (Cr-Pyr) on lipid and protein metabolism in broiler chickens, a total of 400 1-day-old male birds (Aconred) were randomly allocated to four groups, with each group replicating four times and each replicate involving 25 birds. The broilers were provided with a commercial diet supplemented with Cr-Pyr at 0, 1, 5, or 10% of the diet, respectively, for a period of 3 wk ad libitum (from 22 to 42 d). In the present study, body weight (BW) and average daily gain (ADG) of broilers decreased in 10% Cr-Pyr group (P〈0.01), whereas the relative leg and pectoral muscle weights were significantly higher than they were in the control group (P〈0.05). 5 or 10% Cr-Pyr of diets decreased the abdominal fat rate (AFR, abdominal fat/live weight) of the broilers. The serum or hepatic triglyceride (TG) concentrations were significantly lower in the 5 and 10% groups (P〈0.01). In contrast, Cr-Pyr caused a marked increase in the serum nonesterified fatty acid (NEFA), high-density lipoprotein cholesterol (HDL-C) and creatine kinase (CK) concentrations (P〈0.01). Supplementation with Cr-Pyr (5 and 10%) in the diet also increased glucagons (GLU), insulin (INS) or leptin (LEP) contents (P〈0.01). The expression of hepatic peroxisomal proliferators-activated receptor α (PPAR-α) and carnitine palmitoyl transferase-I (CPT-I), muscle insulin-like growth factor I (IGF-I) were significantly elevated and myostatin mRNA level was reduced in the 5 and 10% groups (P〈0.05). It was found that supplementation with 5% Cr-Pyr improves both lipid and protein metabolism by regulating various metabolic parameters of broilers, while not adversely affects growth performance in broiler chickens.
基金Supported by Grant#W911NF0910086 from the United States Department of DefensePredoctoral fellowships from the Graduate School of Biomedical Sciences,University of North Texas Health Science Center to Gurji HA and White DW
文摘AIM: To test the hypothesis that fluid resuscitation with Ringer's solution enriched with pyruvate(PR), a physiological antioxidant and energy substrate, affords protection of myocardial metabolism and electrophysiological performance superior to lactated Ringer's(LR) during hypovolemia and hindlimb ischemia-reperfusion.METHODS: Male domestic goats(25-30 kg) were exsanguinated to a mean arterial pressure of 48 ± 1 mm Hg. Right hindlimb ischemia was imposed for 90 min by applying a tourniquet and femoral crossclamp. LR or PR, infused iv, delivered 0.05 mmol/kg per minute L-lactate or pyruvate, respectively, from 30 min hindlimb ischemia until 30 min post-ischemia. Time controls(TC) underwent neither hemorrhage, hindlimb ischemia nor resuscitation. Goats were sacrificed and left ventricular myocardium biopsied at 90 min fluid resuscitation(n = 6 per group) or 3.5 h later(n = 9 LR, 10 PR, 8 TC).RESULTS: Myocardial 8-isoprostane content, phosphocreatine phosphorylation potential, creatine kinase activity, and heart rate-adjusted QT interval(QTc) vari- ability were evaluated at 90 min resuscitation and 3.5 h post-resuscitation. PR sharply lowered pro-arrhythmic QTc variability vs LR(P < 0.05); this effect persisted 3.5 h post-resuscitation. PR lowered myocardial 8-isoprostane content, a product of oxidative stress, by 39 and 37% during and 3.5 h after resuscitation, respectively, vs LR. Creatine kinase activity fell 42% post-LR vs TC(P < 0.05), but was stable post-PR(P < 0.02 vs post-LR). PR doubled phosphocreatine phosphorylation potential, a measure of ATP free energy state, vs TC and LR(P < 0.05); this energetic enhancement persisted 3.5 h post-resuscitation.CONCLUSION: By augmenting myocardial energy state and protecting creatine kinase activity, pyruvateenriched resuscitation stabilized cardiac electrical function during central hypovolemia and hindlimb ischemiareperfusion.