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1.
AAPS J ; 22(4): 77, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: covidwho-377941

RESUMO

Remdesivir is one of the most promising drugs to treat COVID-19 based on the following facts: remdesivir has a broad-spectrum antiviral mechanism of action; it demonstrated in vitro activity against SARS-CoV-2 and in vivo efficacy in animal models against the similar coronavirus MERS-CoV; its safety profile has been tested in Ebola patients and in compassionate use in COVID-19 patients. Currently, remdesivir is being investigated in ten randomized controlled trials against COVID-19. The dose regimen of remdesivir is an IV loading dose of 200 mg on day 1 followed by daily IV maintenance doses of 100 mg for 5-9 days. Based on our data analysis, however, remdesivir with IV administration alone is unlikely to achieve excellent clinical efficacy. This analysis is based on the following observations: plasma exposures of remdesivir and its active metabolite are unlikely to be correlated with its clinical efficacy; remdesivir and its active metabolites are unlikely to be adequate in the lung to kill the SARS-CoV-2 virus. Even if remdesivir demonstrates benefits in the current randomized controlled trials, its efficacy may be limited. We suggest that a combination of an IV and pulmonary delivery dose regimen should be studied immediately to realize a potentially more effective antiviral therapy against COVID-19. Graphical abstract.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/sangue , Monofosfato de Adenosina/química , Monofosfato de Adenosina/uso terapêutico , Administração por Inalação , Administração Intravenosa , Alanina/administração & dosagem , Alanina/sangue , Alanina/química , Alanina/uso terapêutico , Animais , Humanos , Pandemias
2.
J Antimicrob Chemother ; 75(7): 1772-1777, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: covidwho-154881

RESUMO

BACKGROUND: Remdesivir has received significant attention for its potential application in the treatment of COVID-19, caused by SARS-CoV-2. Remdesivir has already been tested for Ebola virus disease treatment and found to have activity against SARS and MERS coronaviruses. The remdesivir core contains GS-441524, which interferes with RNA-dependent RNA polymerases alone. In non-human primates, following IV administration, remdesivir is rapidly distributed into PBMCs and converted within 2 h to the active nucleoside triphosphate form, while GS-441524 is detectable in plasma for up to 24 h. Nevertheless, remdesivir pharmacokinetics and pharmacodynamics in humans are still unexplored, highlighting the need for a precise analytical method for remdesivir and GS-441524 quantification. OBJECTIVES: The validation of a reliable UHPLC-MS/MS method for remdesivir and GS-441524 quantification in human plasma. METHODS: Remdesivir and GS-441524 standards and quality controls were prepared in plasma from healthy donors. Sample preparation consisted of protein precipitation, followed by dilution and injection into the QSight 220 UHPLC-MS/MS system. Chromatographic separation was obtained through an Acquity HSS T3 1.8 µm, 2.1 × 50 mm column, with a gradient of water and acetonitrile with 0.05% formic acid. The method was validated using EMA and FDA guidelines. RESULTS: Analyte stability has been evaluated and described in detail. The method successfully fulfilled the validation process and it was demonstrated that, when possible, sample thermal inactivation could be a good choice in order to improve biosafety. CONCLUSIONS: This method represents a useful tool for studying remdesivir and GS-441524 clinical pharmacokinetics, particularly during the current COVID-19 outbreak.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Doença pelo Vírus Ebola/tratamento farmacológico , Espectrometria de Massas em Tandem/métodos , Monofosfato de Adenosina/análise , Monofosfato de Adenosina/sangue , Monofosfato de Adenosina/farmacocinética , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/sangue , Trifosfato de Adenosina/farmacocinética , Alanina/análise , Alanina/sangue , Alanina/farmacocinética , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Humanos , Pandemias , Pneumonia Viral/tratamento farmacológico , Sensibilidade e Especificidade
3.
J Antimicrob Chemother ; 75(7): 1772-1777, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32361744

RESUMO

BACKGROUND: Remdesivir has received significant attention for its potential application in the treatment of COVID-19, caused by SARS-CoV-2. Remdesivir has already been tested for Ebola virus disease treatment and found to have activity against SARS and MERS coronaviruses. The remdesivir core contains GS-441524, which interferes with RNA-dependent RNA polymerases alone. In non-human primates, following IV administration, remdesivir is rapidly distributed into PBMCs and converted within 2 h to the active nucleoside triphosphate form, while GS-441524 is detectable in plasma for up to 24 h. Nevertheless, remdesivir pharmacokinetics and pharmacodynamics in humans are still unexplored, highlighting the need for a precise analytical method for remdesivir and GS-441524 quantification. OBJECTIVES: The validation of a reliable UHPLC-MS/MS method for remdesivir and GS-441524 quantification in human plasma. METHODS: Remdesivir and GS-441524 standards and quality controls were prepared in plasma from healthy donors. Sample preparation consisted of protein precipitation, followed by dilution and injection into the QSight 220 UHPLC-MS/MS system. Chromatographic separation was obtained through an Acquity HSS T3 1.8 µm, 2.1 × 50 mm column, with a gradient of water and acetonitrile with 0.05% formic acid. The method was validated using EMA and FDA guidelines. RESULTS: Analyte stability has been evaluated and described in detail. The method successfully fulfilled the validation process and it was demonstrated that, when possible, sample thermal inactivation could be a good choice in order to improve biosafety. CONCLUSIONS: This method represents a useful tool for studying remdesivir and GS-441524 clinical pharmacokinetics, particularly during the current COVID-19 outbreak.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Doença pelo Vírus Ebola/tratamento farmacológico , Espectrometria de Massas em Tandem/métodos , Monofosfato de Adenosina/análise , Monofosfato de Adenosina/sangue , Monofosfato de Adenosina/farmacocinética , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/sangue , Trifosfato de Adenosina/farmacocinética , Alanina/análise , Alanina/sangue , Alanina/farmacocinética , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Humanos , Pandemias , Pneumonia Viral/tratamento farmacológico , Sensibilidade e Especificidade
4.
AAPS J ; 22(4): 77, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32458279

RESUMO

Remdesivir is one of the most promising drugs to treat COVID-19 based on the following facts: remdesivir has a broad-spectrum antiviral mechanism of action; it demonstrated in vitro activity against SARS-CoV-2 and in vivo efficacy in animal models against the similar coronavirus MERS-CoV; its safety profile has been tested in Ebola patients and in compassionate use in COVID-19 patients. Currently, remdesivir is being investigated in ten randomized controlled trials against COVID-19. The dose regimen of remdesivir is an IV loading dose of 200 mg on day 1 followed by daily IV maintenance doses of 100 mg for 5-9 days. Based on our data analysis, however, remdesivir with IV administration alone is unlikely to achieve excellent clinical efficacy. This analysis is based on the following observations: plasma exposures of remdesivir and its active metabolite are unlikely to be correlated with its clinical efficacy; remdesivir and its active metabolites are unlikely to be adequate in the lung to kill the SARS-CoV-2 virus. Even if remdesivir demonstrates benefits in the current randomized controlled trials, its efficacy may be limited. We suggest that a combination of an IV and pulmonary delivery dose regimen should be studied immediately to realize a potentially more effective antiviral therapy against COVID-19. Graphical abstract.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/sangue , Monofosfato de Adenosina/química , Monofosfato de Adenosina/uso terapêutico , Administração por Inalação , Administração Intravenosa , Alanina/administração & dosagem , Alanina/sangue , Alanina/química , Alanina/uso terapêutico , Animais , Humanos , Pandemias
5.
Ann Rheum Dis ; 79(4): 499-506, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32079570

RESUMO

OBJECTIVES: The differential diagnosis of seronegative rheumatoid arthritis (negRA) and psoriasis arthritis (PsA) is often difficult due to the similarity of symptoms and the unavailability of reliable clinical markers. Since chronic inflammation induces major changes in the serum metabolome and lipidome, we tested whether differences in serum metabolites and lipids could aid in improving the differential diagnosis of these diseases. METHODS: Sera from negRA and PsA patients with established diagnosis were collected to build a biomarker-discovery cohort and a blinded validation cohort. Samples were analysed by proton nuclear magnetic resonance. Metabolite concentrations were calculated from the spectra and used to select the variables to build a multivariate diagnostic model. RESULTS: Univariate analysis demonstrated differences in serological concentrations of amino acids: alanine, threonine, leucine, phenylalanine and valine; organic compounds: acetate, creatine, lactate and choline; and lipid ratios L3/L1, L5/L1 and L6/L1, but yielded area under the curve (AUC) values lower than 70%, indicating poor specificity and sensitivity. A multivariate diagnostic model that included age, gender, the concentrations of alanine, succinate and creatine phosphate and the lipid ratios L2/L1, L5/L1 and L6/L1 improved the sensitivity and specificity of the diagnosis with an AUC of 84.5%. Using this biomarker model, 71% of patients from a blinded validation cohort were correctly classified. CONCLUSIONS: PsA and negRA have distinct serum metabolomic and lipidomic signatures that can be used as biomarkers to discriminate between them. After validation in larger multiethnic cohorts this diagnostic model may become a valuable tool for a definite diagnosis of negRA or PsA patients.


Assuntos
Artrite Psoriásica/sangue , Artrite Reumatoide/sangue , Acetatos/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina/sangue , Aminoácidos/sangue , Artrite Psoriásica/diagnóstico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/imunologia , Colina/sangue , Creatina/sangue , Diagnóstico Diferencial , Feminino , Humanos , Ácido Láctico/sangue , Lipidômica , Lipídeos/sangue , Masculino , Metaboloma , Metabolômica , Pessoa de Meia-Idade , Fosfocreatina/sangue , Espectroscopia de Prótons por Ressonância Magnética , Ácido Succínico/sangue
6.
Pharmacol Biochem Behav ; 185: 172760, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31422081

RESUMO

BACKGROUND: D-amino acids have been recognized as bioactive substances in humans. d-Serine and D-alanine are co-agonists of N-methyl-d-aspartate receptors. Glutamate has been suggested to be involved in the pathophysiology of Alzheimer's disease (AD). This study aimed to explore the roles of amino acids, particularly D-amino acids, in cognitive decline among patients with AD or mild cognitive impairment (MCI). METHODS: We enrolled 144 patients: 20 amnestic MCI, 85 mild AD, 25 moderate AD, and 14 severe AD. Serum levels of amino acids were measured by high performance liquid chromatography and confirmed by D-amino acid oxidase assay. The cognitive function was mainly evaluated by Alzheimer's Disease Assessment Scale - Cognitive Subscale (ADAS-cog). RESULTS: ADAS-cog total scores were positively correlated with d-serine (r = 0.186, p = 0.026) and D-/Total- serine ratio (r = 0.191, p = 0.022). ADAS-cog behavior scores were negatively correlated with D-glutamate (r = -0.177, p = 0.034) and L-glutamate (r = -0.250, p = 0.003), but positively correlated with D-alanine (r = 0.236, p = 0.005) and D-/Total- alanine ratio (r = 0.252, p = 0.002). Among the 11 tasks of ADAS-cog, D-glutamate and d-serine were correlated with different items respectively, noteworthily in the opposite direction. CONCLUSION: This is the first study suggesting that D-amino acids in blood may be correlated with ADAS-cog in different items and in the opposite direction. Lower D-glutamate and higher D-alanine levels may predict more behavioral symptoms. In summary, D-glutamate, d-serine and D-alanine play different and characteristic roles in AD. Further longitudinal studies are warranted to elucidate the function and interaction of D-amino acids in specific cognitive domains as well as various phases of dementia.


Assuntos
Alanina/sangue , Doença de Alzheimer/sangue , Doença de Alzheimer/psicologia , Disfunção Cognitiva/sangue , Ácido Glutâmico/sangue , Serina/sangue , Idoso , Idoso de 80 Anos ou mais , Sintomas Comportamentais/sangue , Cromatografia Líquida , Cognição/fisiologia , Estudos de Coortes , Estudos Transversais , Dieta , Feminino , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Taiwan
7.
Methods Mol Biol ; 2030: 293-306, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31347126

RESUMO

L-Pyroglutamic acid succinimidyl ester (L-PGA-OSu) and its isotopic variant (L-PGA[d5]-OSu) were synthesized and used as the chiral labeling reagents for the enantioseparation of amino acids by reversed-phase UPLC-ESI-MS/MS. The enantiomers of amino acids were labeled with the reagents at 60 °C for 10 min in an alkaline medium. The resulting diastereomers were well separated by the reversed-phase chromatography using an ODS column, packed with small particles (1.7 µm) (Rs = 1.95-8.05). A highly sensitive detection at a low-fmol level (0.5-3.2 fmol) was obtained from the selected reaction monitoring (SRM) chromatograms. An isotope labeling strategy using light and heavy variants for the differential analysis of the DL-amino acids in different sample groups is also presented in this paper. The ratios of D/L-alanine in different yogurt products were successfully determined by the proposed method. The D/L ratios were almost comparable to those obtained from only using light reagent (i.e., L-PGA-OSu). Therefore, the proposed strategy seems to be useful for the differential analysis of DL-amino acids, not only in food products but also in biological samples.


Assuntos
Alanina/isolamento & purificação , Cromatografia de Fase Reversa/métodos , Marcação por Isótopo/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Alanina/sangue , Alanina/química , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/instrumentação , Estudos de Viabilidade , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Humanos , Hidrogênio/química , Marcação por Isótopo/instrumentação , Ácido Pirrolidonocarboxílico/química , Radioisótopos/química , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Estereoisomerismo , Succinatos/química , Espectrometria de Massas em Tandem/instrumentação , Iogurte/análise
8.
Methods Mol Biol ; 2007: 9-17, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148103

RESUMO

In the context of the vascular effects of hydrogen sulfide (H2S), it is known that this gaseous endogenous biological modulator of inflammation, oxidative stress, etc. is a potent vasodilator. Chronic renal failure, a common disease affecting the aging population, is characterized by low levels of H2S in plasma and tissues, which could mediate their typical hypertensive pattern, along with other abnormalities. Lanthionine and homolanthionine, natural non-proteinogenic amino acids, are formed as side products of H2S production. Also in consideration of the intrinsic difficulties in H2S measuring, these compounds have been proposed as reliable and stable markers of H2S synthesis. However, in the setting of chronic renal failure patients on hemodialysis, they represent typical retention products (without ruling out the possibility of an increased intestinal synthesis) and prospective novel uremic toxins. Here, a method utilizing liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) in multiple reaction monitoring ion mode has been developed and evaluated for the determination of these key H2S metabolites in plasma, by using a triple quadrupole mass spectrometer.


Assuntos
Alanina/análogos & derivados , Aminoácidos Sulfúricos/sangue , Sulfeto de Hidrogênio/sangue , Insuficiência Renal Crônica/sangue , Sulfetos/sangue , Espectrometria de Massas em Tandem/métodos , Alanina/sangue , Cromatografia Líquida/métodos , Humanos , Masculino , Diálise Renal , Insuficiência Renal Crônica/terapia
9.
Food Res Int ; 116: 1239-1246, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30716911

RESUMO

The potential health benefit of dietary fiber has attracted considerable attention in recent decades. In this study, the effects of modified dietary fibers (MDF) derived from okara on body composition, fat distribution, serum metabolomic parameters, and fatty acid profiles in mice fed high-fat diets (HFD) were evaluated by nuclear magnetic resonance (NMR)-based metabolic approach. HFD-induced C57BL mice were fed with a diet containing 100 g/kg MDF for 12 weeks. Compared with control mice, MDF-fed mice exhibited less fat and lower body weights, altered serum metabolomic profiles, and distinct fatty acid profiles. The levels of choline, phosphatidylcholine, glycerophosphorylcholine, glucose, lysine, scyllo-inositol, and glutamate for MDF group were higher than those for both CONT and HFD groups. A remarkable reduction of total cholesterol, total triglycerides, ω-6 fatty acids, alanine, citrate, creatine, or succinate was also observable for MDF group compared with HFD group. These findings demonstrated that the intake of MDF derived from okara clearly ameliorated some of the HFD-induced adverse metabolic effects and prevented adipose tissue accumulation.


Assuntos
Composição Corporal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Fibras na Dieta/uso terapêutico , Ácidos Graxos/metabolismo , Tecido Adiposo/metabolismo , Alanina/sangue , Animais , Glicemia , Peso Corporal , Colesterol/sangue , Colina/sangue , Ácido Cítrico/sangue , Ácidos Graxos/sangue , Ácidos Graxos Ômega-6/sangue , Ácido Glutâmico/sangue , Glicerilfosforilcolina/sangue , Inositol/sangue , Lisina/sangue , Espectroscopia de Ressonância Magnética , Masculino , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilcolinas/sangue , Soja , Ácido Succínico/sangue , Triglicerídeos/sangue
10.
PLoS One ; 14(1): e0209910, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30608977

RESUMO

Seminal plasma is a key biological fluid that modulates sperm function in the reproduction process. However, its role in sperm biotechnologies is scarce in poultry. The aims of the present study were to study the amino acids profile and total proteins of seminal plasma in 12 Spanish chicken breeds and to investigate the role of seminal plasma on cryoresistance of rooster sperm. To investigate the role of seminal plasma on cryoresistance, diluted pooled semen samples were cryopreserved in the presence and absence of seminal plasma. Glutamic acid was the most abundant free amino acid in seminal plasma, followed by alanine, serine, valine, and glycine. There was an influence of breed (P<0.05) on the percentage of viable sperm after freezing-thawing of samples with seminal plasma. Cluster analysis revealed that White Prat, Black Castellana, Blue Andaluza, Quail Castellana, and Red-Barred Vasca returned the best freezing-thawing response (good freezers). There was a positive correlation between seminal plasma concentrations of valine, isoleucine lysine, leucine and post thaw viability. The evaluation of fertilization capacity of frozen-thawed semen from the breeds White Prat ('good freezer') and Black-Red Andaluza ('bad freezer') showed that good freezer had higher fertility (20/68, 29.4%) compared to bad freezer breed (14/76, 18.4%), even if the difference was not significant (P = 0.08). The TUNEL assay revealed that freezing/thawing procedures in presence of seminal plasma provoked higher DNA fragmentation in most of the breeds, with a positive correlation between seminal alanine, valine, isoleucine, methionine, leucine, tyrosine, phenylalanine concentrations and DNA integrity. DNA fragmentation was lower in absence of seminal plasma and the breed effect on sperm viability was highly reduced. It is concluded that specific seminal plasma amino acids were associated with post-thaw percentage of viable sperm and DNA integrity. The removal of seminal plasma decreases the variability of the results and DNA fragmentation damages.


Assuntos
Aminoácidos/sangue , Sêmen/fisiologia , Espermatozoides/fisiologia , Alanina/sangue , Animais , Galinhas , Criopreservação/métodos , Fragmentação do DNA , Ácido Glutâmico/sangue , Glicina/sangue , Marcação In Situ das Extremidades Cortadas , Masculino , Serina/sangue , Valina/sangue
11.
J Trace Elem Med Biol ; 50: 652-657, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30269758

RESUMO

Wilson's disease (WD) is caused by mutations in the ATP7B gene responsible for a toxic copper overload mainly in the liver and the central nervous system. Phenotypic heterogeneity may challenge the diagnostic confirmation. Exchangeable copper (CuEXC) has recently been proposed as a new marker of WD, and its ratio to the total serum copper (Cus), Relative Exchangeable Copper (REC = CuEXC/Cus), as a diagnostic marker. This study aimed to investigate whether this could be confirmed in Atp7b-/- mice, an engineered WD animal model. Atp7b-/- (n = 137) and wild type (WT; n = 101) mice were investigated under the same conditions at 6-8, 20, 39, or 50 weeks of age. Twenty-four Atp7b-/- mice received D-penicillamine treatment from 39 to 50 weeks of age. Serum and liver [histology and intrahepatic copper (IHCu)] data were evaluated. In the WT group, all serum and liver data were normal. Atp7b-/- livers developed a chronic injury from isolated moderate inflammation (6-8 weeks: 16/33 = 48%) to inflammatory fibrosis with cirrhosis (50 weeks: 25/25 = 100% and 16/25 = 64% respectively). Cus and CuEXC increased until week 39, whereas IHCu and REC were stable with increasing age and much higher than in WT mice (mean ±â€¯SD: 669 ±â€¯269 vs. 13 ±â€¯3 µg/g dry liver and 39 ±â€¯12 vs. 11 ±â€¯3%, respectively). A threshold value of 20% for REC provided a diagnostic sensitivity and specificity of 100%, regardless of sex, age, or the use of D-penicillamine. Eleven weeks of 100 mg/kg D-penicillamine reduced liver fibrosis (p = 0.001), IHCu (p = 0.026) and CuEXC (p = 0.175). In conclusion, this study confirms REC as a WD diagnostic marker in a mouse model of chronic liver disease caused by copper overload. Further studies are needed to assess the usefulness of CuEXC to monitor the evolution of WD, particularly during treatment.


Assuntos
Cobre/sangue , Degeneração Hepatolenticular/sangue , Adenosina Trifosfatases/sangue , Alanina/sangue , Animais , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Biomarcadores/sangue , ATPases Transportadoras de Cobre/genética , Modelos Animais de Doenças , Fibrose/sangue , Fibrose/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação/genética
12.
Mol Genet Metab ; 125(1-2): 73-78, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30037504

RESUMO

BACKGROUND: 1-Deoxysphingolipids (1-deoxySLs) are atypical sphingolipids. They are formed during sphingolipid de novo synthesis by the enzyme serine palmitoyltransferase, due to the alternate use of alanine over its canonical substrate serine. Pathologically elevated 1-deoxySL are involved in several neurological and metabolic disorders. The objective of this study was to investigate the role of 1-deoxySL in glycogen storage disease type I (GSDI). METHODS: In this prospective, longitudinal observational study (median follow-up 1.8y), the plasma 1-deoxySL profile was analyzed in 15 adult GSDI patients (12 GSDIa, 3 GSDIb), and 31 healthy controls, along with standard parameters for monitoring GSDI. RESULTS: 1-Deoxysphinganine (1-deoxySA) concentrations were elevated in GSDI compared to controls (191 ±â€¯129 vs 35 ±â€¯14 nmol/l, p < 0.0001). Concordant with the mechanism of 1-deoxySL synthesis, plasma alanine was higher (625 ±â€¯182 vs 398 ±â€¯90 µmol/l, p < 0.0001), while serine was lower in GSDI than in controls (88 ±â€¯22 vs 110 ±â€¯18 µmol/l. p < 0.001). Accordingly, serine, alanine and triglycerides were determinants of 1-deoxySA in the longitudinal analysis of GSDIa. 1-deoxySA concentrations correlated with the occurrence of low blood glucose (area under the curve below 4 mmol/l) in continuous glucose monitoring. The 1-deoxySL profile in GSDIb was distinct from GSDIa, with a different ratio of saturated to unsaturated 1-deoxySL. CONCLUSION: In addition to the known abnormalities of lipoproteins, GSDI patients also have a disturbed sphingolipid metabolism with elevated plasma 1-deoxySL concentrations. 1-DeoxySA relates to the occurrence of low blood glucose, and may constitute a potential new biomarker for assessing metabolic control. GSDIa and Ib have distinct 1-deoxySL profiles indicating that both GSD subtypes have diverse phenotypes regarding lipid metabolism.


Assuntos
Doença de Depósito de Glicogênio Tipo I/sangue , Metabolismo dos Lipídeos/genética , Esfingolipídeos/sangue , Adolescente , Adulto , Alanina/sangue , Feminino , Glucose/metabolismo , Doença de Depósito de Glicogênio Tipo I/genética , Doença de Depósito de Glicogênio Tipo I/patologia , Humanos , Masculino , Serina/sangue , Serina C-Palmitoiltransferase/genética , Esfingolipídeos/genética , Adulto Jovem
13.
J Nutr Biochem ; 60: 24-34, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30041049

RESUMO

Docosahexaenoic acid (DHA, 22:6n-3) must be consumed in the diet or synthesized from n-3 polyunsaturated fatty acid (PUFA) precursors. However, the effect of dietary DHA on the metabolic pathway is not fully understood. Presently, 21-day-old Long Evans rats were weaned onto one of four dietary protocols: 1) 8 weeks of 2% ALA (ALA), 2) 6 weeks ALA followed by 2 weeks of 2% ALA + 2% DHA (DHA), 3) 4 weeks ALA followed by 4 weeks DHA and 4) 8 weeks of DHA. After the feeding period, 2H5-ALA and 13C20-eicosapentaenoic acid (EPA, 20:5n-3) were co-infused and blood was collected over 3 h for determination of whole-body synthesis-secretion kinetics. The synthesis-secretion coefficient (ml/min, means ± SEM) for EPA (0.238±0.104 vs. 0.021±0.001) and DPAn-3 (0.194±0.060 vs. 0.020±0.008) synthesis from plasma unesterified ALA, and DPAn-3 from plasma unesterified EPA (2.04±0.89 vs. 0.163±0.025) were higher (P<.05) after 2 weeks compared to 8 weeks of DHA feeding. The daily synthesis-secretion rate (nmol/d) of DHA from EPA was highest after 4 weeks of DHA feeding (843±409) compared to no DHA (70±22). Liver gene expression of ELOVL2 and FADS2 were lower (P<.05) after 4 vs. 8 weeks of DHA. Higher synthesis-secretion kinetics after 2 and 4 weeks of DHA feeding suggests an increased throughput of the PUFA metabolic pathway. Furthermore, these findings may lead to novel dietary strategies to maximize DHA levels while minimizing dietary requirements.


Assuntos
Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Graxos Ômega-3/sangue , Alanina/administração & dosagem , Alanina/sangue , Animais , Isótopos de Carbono , Deutério , Suplementos Nutricionais , Ácido Eicosapentaenoico/administração & dosagem , Ácido Eicosapentaenoico/sangue , Ácidos Graxos Ômega-3/biossíntese , Cinética , Fígado/enzimologia , Masculino , RNA Mensageiro/análise , Ratos , Ratos Long-Evans , Fatores de Tempo
14.
Artigo em Inglês | MEDLINE | ID: mdl-29911073

RESUMO

Purpose: To explore the metabolic characterization of host responses to drainage-resistant Klebsiella pneumoniae liver abscesses (DRKPLAs) with serum 1H-nuclear magnetic resonance (NMR) spectroscopy. Materials and Methods: The hospital records of all patients with a diagnosis of a liver abscess between June 2015 and December 2016 were retrieved from an electronic hospital database. Eighty-six patients with Klebsiella pneumoniae (K. pneumoniae) liver abscesses who underwent percutaneous drainage were identified. Twenty patients with confirmed DRKPLAs were studied. Moreover, we identified 20 consecutive patients with drainage-sensitive Klebsiella pneumoniae liver abscesses (DSKPLAs) as controls. Serum samples from the two groups were analyzed with 1H NMR spectroscopy. Partial least squares discriminant analysis (PLS-DA) was used to perform 1H NMR metabolic profiling. Metabolites were identified using the Human Metabolome Database, and pathway analysis was performed with MetaboAnalyst 3.0. Results: The PLS-DA test was able to discriminate between the two groups. Five key metabolites that contributed to their discrimination were identified. Glucose, lactate, and 3-hydroxybutyrate were found to be upregulated in DRKPLAs, whereas glutamine and alanine were downregulated compared with the DSKPLAs. Pathway analysis indicated that amino acid metabolisms were significantly different between the DRKPLAs and the DSKPLAs. The D-glutamine and D-glutamate metabolisms exhibited the greatest influences. Conclusions: The five key metabolites identified in our study may be potential targets for guiding novel therapeutics of DRKPLAs and are worthy of additional investigation.


Assuntos
Infecções por Klebsiella/sangue , Klebsiella pneumoniae/patogenicidade , Abscesso Hepático/metabolismo , Metaboloma , Paracentese/métodos , Espectroscopia de Prótons por Ressonância Magnética/métodos , Ácido 3-Hidroxibutírico/sangue , Adulto , Idoso , Alanina/sangue , Aminoácidos/metabolismo , Glicemia , Farmacorresistência Bacteriana Múltipla , Feminino , Glutamina/sangue , Humanos , Citometria por Imagem , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/terapia , Ácido Láctico/sangue , Abscesso Hepático/diagnóstico por imagem , Abscesso Hepático/microbiologia , Abscesso Hepático/patologia , Subpopulações de Linfócitos , Masculino , Metabolômica/métodos , Pessoa de Meia-Idade
15.
J Pak Med Assoc ; 68(4): 510-514, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29808036

RESUMO

OBJECTIVE: To determine the frequency of disorders leading to methylmalonic acidurias. METHODS: This cross-sectional study was conducted from January 2013 to April 2016 at the Aga Khan University Hospital, Karachi, and comprised patients diagnosed with methylmalonic acidurias based on urine organic acid analysis. Clinical history and biochemical data was collected from the biochemical genetics laboratory requisition forms. Organic acid chromatograms of all the subjects were critically reviewed by a biochemical pathologist and a metabolic physician. For assessing the clinical outcome, medical charts of the patients were reviewed. SPSS 19 was used for data analysis. RESULTS: Of the 1,778 patients 50(2.81%) were detected with methylmalonic acidurias. After excluding patients with non-significant peaks of methylmalonic acidemia, 41(2.31%) were included in the final analysis. Of these, 20(48.7%) were females, while the overall median age was 11.5 months (interquartile range: 6-41.5). On stratification by type of disorders leading to methylmalonic acidurias, 9(22%) had methylmalonic acidemia, 12(29%) had Cobalamin-related remethylation disorders, nonspecific methylmalonic acidurias in 16(39%), while 2(5%) each had succinyl coenzyme A synthetase and Vitamin B12 deficiency. respectively. CONCLUSIONS: Screening tests, including urine organic acid, provided valuable clues to the aetiology of methylmalonic acidurias.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/etiologia , Doenças Mitocondriais/complicações , Deficiência de Vitamina B 12/complicações , Alanina/sangue , Erros Inatos do Metabolismo dos Aminoácidos/sangue , Erros Inatos do Metabolismo dos Aminoácidos/urina , Pré-Escolar , Citratos/urina , Estudos Transversais , Feminino , Glicina/análogos & derivados , Glicina/sangue , Glicina/urina , Humanos , Lactente , Ácido Láctico/análogos & derivados , Ácido Láctico/urina , Masculino , Metionina/sangue , Paquistão , Centros de Atenção Terciária , Urinálise/métodos , Valeratos/urina
16.
Clin Chim Acta ; 480: 214-219, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29474999

RESUMO

BACKGROUND: Parkinson's disease (PD) is the result of progressive degeneration of the nigrostriatal dopaminergic pathway and depletion of neurotransmitter dopamine in the striatum. METHODS: We included 17 patients with PD along with 7 patients of progressive supranuclear palsy (PSP), 6 patients of multiple system atrophy (MSA) and 22 age and sex-matched healthy controls. We analyzed metabolite profiles in the serum of these patients and controls using 1H NMR spectroscopy. RESULTS: Isoleucine, valine, alanine, glutamine and histidine in PD, PSP and MSA were significantly (P < 0.001) higher than controls, whereas, glutamate and glucose were significantly increased in PD (P < 0.001), PSP and MSA (P < 0.05) vs. CONTROL: Citrate was increased in PD, PSP and MSA (P < 0.05) vs. CONTROL: While, acetone, lactate and formate were higher at P < 0.001, threonine is increased at P < 0.05. The 3D scattered score plot of OPLS-DA model revealed clear differentiation among the groups, R2 = 0.92 and Q2 = 0.78. CONCLUSION: Significant differences in various metabolite levels were found between control and disease groups. Common amino acids that are significantly higher in all groups include branched chain amino acids, which could increase neuronal excitability.


Assuntos
Metabolômica , Doença de Parkinson/sangue , Idoso , Alanina/sangue , Feminino , Glutamina/sangue , Histidina/sangue , Humanos , Índia , Isoleucina/sangue , Masculino , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/sangue , Atrofia de Múltiplos Sistemas/metabolismo , Doença de Parkinson/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Paralisia Supranuclear Progressiva/sangue , Paralisia Supranuclear Progressiva/metabolismo , Valina/sangue
17.
Diabetologia ; 61(3): 671-680, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29305624

RESUMO

AIMS/HYPOTHESIS: The secretion of glucagon is controlled by blood glucose and inappropriate secretion of glucagon contributes to hyperglycaemia in diabetes. Besides its role in glucose regulation, glucagon regulates amino acid metabolism in hepatocytes by increasing ureagenesis. Disruption of this mechanism causes hyperaminoacidaemia, which in turn increases glucagon secretion. We hypothesised that hepatic insulin resistance (secondary to hepatic steatosis) via defective glucagon signalling/glucagon resistance would lead to impaired ureagenesis and, hence, increased plasma concentrations of glucagonotropic amino acids and, subsequently, glucagon. METHODS: To examine the association between glucagon and amino acids, and to explore whether this relationship was modified by hepatic insulin resistance, we studied a well-characterised cohort of 1408 individuals with normal and impaired glucose regulation. In this cohort, we have previously reported insulin resistance to be accompanied by increased plasma concentrations of glucagon. We now measure plasma levels of amino acids in the same cohort. HOMA-IR was calculated as a marker of hepatic insulin resistance. RESULTS: Fasting levels of glucagonotropic amino acids and glucagon were significantly and inversely associated in linear regression models (persisting after adjustment for age, sex and BMI). Increasing levels of hepatic, but not peripheral insulin resistance (p > 0.166) attenuated the association between glucagon and circulating levels of alanine, glutamine and tyrosine, and was significantly associated with hyperaminoacidaemia and hyperglucagonaemia. A doubling of the calculated glucagon-alanine index was significantly associated with a 30% increase in hepatic insulin resistance, a 7% increase in plasma alanine aminotransferase levels, and a 14% increase in plasma γ-glutamyltransferase levels. CONCLUSIONS/INTERPRETATION: This cross-sectional study supports the existence of a liver-alpha cell axis in humans: glucagon regulates plasma levels of amino acids, which in turn feedback to regulate the secretion of glucagon. With hepatic insulin resistance, reflecting hepatic steatosis, the feedback cycle is disrupted, leading to hyperaminoacidaemia and hyperglucagonaemia. The glucagon-alanine index is suggested as a relevant marker for hepatic glucagon signalling.


Assuntos
Aminoácidos/sangue , Glucagon/sangue , Resistência à Insulina/fisiologia , Fígado/citologia , Fígado/metabolismo , Idoso , Alanina/sangue , Estudos Transversais , Feminino , Teste de Tolerância a Glucose , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade
18.
J Nutr ; 148(1): 40-48, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29378055

RESUMO

Background: Fructose feeding in the context of high energy intake is recognized as being responsible for metabolic dysregulation. However, its consumption in the postabsorptive state might contribute to reducing the use of amino acids (AAs) as energy substrates and thus spare nitrogen resources, which could be beneficial during catabolic states. Objective: We hypothesized that fructose feeding during a catabolic situation corresponding to protein-energy restriction (PER) in older rats would reduce AA utilization for energy purposes, thus slowing down the loss of body weight (BW) and improving body composition. Methods: For 45 d, 22-mo-old male Wistar rats (average weight: 716 g) were fed a control ration (13% protein) either at normal (20 g/d), restricted (PER: 10 g/d), or at PER levels supplemented with glucose (3 g/d) or fructose (3 g/d) and then studied in the postabsorptive state. We measured BW, body composition, and enzyme activities and metabolite concentrations related to glucose, fructose, and AA metabolism. Results: Both glucose and fructose feeding reduced PER-induced loss of BW and lean mass (-27% compared with PER), but only fructose reduced the loss of fat mass (-28% compared with PER). Fructose feeding prevented the PER-induced loss of muscle and intestinal mass. Fructose feeding also reduced circulating branched-chain AA concentrations by 50% (compared with PER) and increased those of alanine (+65% compared with PER). A reduction in hepatic enzymes related to AA catabolism was also observed during fructose feeding (compared with PER), whereas glycogen concentrations were enhanced in both intestine (+300%) and muscle (+21%). Conclusions: We showed that in PER older rats, fructose feeding improved body composition and the weight of several organs by reducing AA catabolism and utilization for energy production and liver autophagy potential. This could be advantageous in sparing body proteins, particularly during catabolic states, such as those related to malnutrition during aging.


Assuntos
Composição Corporal , Dieta com Restrição de Proteínas , Frutose/administração & dosagem , Nitrogênio/metabolismo , Alanina/sangue , Alanina Desidrogenase/sangue , Aminoácidos de Cadeia Ramificada/sangue , Animais , Glicemia/metabolismo , Glicogênio/metabolismo , Insulina/sangue , Ácido Láctico/sangue , Leucina Desidrogenase/sangue , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar , Ureia/sangue
19.
Biochem Biophys Res Commun ; 496(2): 267-273, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29294327

RESUMO

Migraine is a highly disabling primary headache associated with a high socioeconomic burden and a generally high prevalence. The clinical management of migraine remains a challenge. This study was undertaken to identify potential serum biomarkers of migraine. Using Liquid Chromatography coupled to Mass Spectrometry (LC-MS), the metabolomic profile of migraine was compared with healthy individuals. Principal component analysis (PCA) and Orthogonal partial least squares-discriminant analysis (orthoPLS-DA) showed the metabolomic profile of migraine is distinguishable from controls. Volcano plot analysis identified 10 serum metabolites significantly decreased during migraine. One of these was serotonin, and the other 9 were amino acids. Pathway analysis and enrichment analysis showed tryptophan metabolism (serotonin metabolism), arginine and proline metabolism, and aminoacyl-tRNA biosynthesis are the three most prominently altered pathways in migraine. ROC curve analysis indicated Glycyl-l-proline, N-Methyl-dl-Alanine and l-Methionine are potential sensitive and specific biomarkers for migraine. Our results show Glycyl-l-proline, N-Methyl-dl-Alanine and l-Methionine may be as specific or more specific for migraine than serotonin which is the traditional biomarker of migraine. We propose that therapeutic manipulation of these metabolites or metabolic pathways may be helpful in the prevention and treatment of migraine.


Assuntos
Alanina/análogos & derivados , Dipeptídeos/sangue , Metionina/sangue , Transtornos de Enxaqueca/diagnóstico , Serotonina/sangue , Adulto , Alanina/sangue , Arginina/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão/métodos , Análise Discriminante , Feminino , Humanos , Masculino , Metaboloma , Transtornos de Enxaqueca/sangue , Transtornos de Enxaqueca/fisiopatologia , Análise de Componente Principal , Prolina/sangue , Aminoacil-RNA de Transferência/sangue , Curva ROC , Triptofano/sangue
20.
J Nutr ; 147(9): 1658-1668, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28794210

RESUMO

Background: An elevated circulating cystathionine concentration, which arises in part from insufficiencies of vitamin B-6, B-12, or folate, has been shown to be associated with cardiovascular disease (CVD) risk. Hydrogen sulfide (H2S) is a gasotransmitter involved in vasodilation, neuromodulation, and inflammation. Most endogenously produced H2S is formed by pyridoxal phosphate (PLP)-dependent enzymes by noncanonical reactions of the transsulfuration pathway that yield H2S concurrently form lanthionine and homolanthionine. Thus, plasma lanthionine and homolanthionine concentrations can provide relative information about H2S production in vivo.Objective: To determine the metabolic consequences of an elevated plasma cystathionine concentration in adults with stable angina pectoris (SAP), we conducted both targeted and untargeted metabolomic analyses.Methods: We conducted NMR and LC-mass spectrometry (MS) metabolomic analyses on a subset of 80 plasma samples from the Western Norway Coronary Angiography Cohort and selected, based on plasma cystathionine concentrations, a group with high cystathionine concentrations [1.32 ± 0.60 µmol/L (mean ± SD); n = 40] and a group with low cystathionine concentrations [0.137 ± 0.011 µmol/L (mean ± SD); n = 40]. Targeted and untargeted metabolomic analyses were performed and assessed with the use of Student's t tests corrected for multiple testing. Overall differences between the cystathionine groups were assessed by untargeted NMR and LC-MS metabolomic methods and evaluated by partial least squares discriminant analysis (PLS-DA) with significant discriminating metabolites identified with 99% confidence.Results: Subjects with high cystathionine concentrations had 75% higher plasma lanthionine concentrations (0.12 ± 0.044 µmol/L) than subjects with low cystathionine concentrations [0.032 ± 0.013 µmol/L (P < 0.001)]. Although plasma homolanthionine concentrations were notably higher than lanthionine concentrations, they were not different between the groups (P = 0.47). PLS-DA results showed that a high plasma cystathionine concentration in SAP was associated with higher glucose, branched-chain amino acids, and phenylalanine concentrations, lower kidney function, and lower glutathione and plasma PLP concentrations due to greater catabolism. The high-cystathionine group had a greater proportion of subjects in the postprandial state.Conclusion: These data suggest that metabolic perturbations consistent with higher CVD risk exist in SAP patients with elevated plasma cystathionine concentrations.


Assuntos
Angina Estável/etiologia , Cistationina/sangue , Redes e Vias Metabólicas , Alanina/análogos & derivados , Alanina/sangue , Aminoácidos de Cadeia Ramificada/sangue , Angina Estável/sangue , Glicemia/metabolismo , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Feminino , Glutationa/sangue , Homocisteína/sangue , Humanos , Sulfeto de Hidrogênio/sangue , Rim/metabolismo , Masculino , Espectrometria de Massas , Metaboloma , Pessoa de Meia-Idade , Estado Nutricional , Fenilalanina/sangue , Fosfato de Piridoxal/sangue , Risco , Sulfetos/sangue , Complexo Vitamínico B/sangue , Deficiência de Vitaminas do Complexo B/sangue , Deficiência de Vitaminas do Complexo B/complicações
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