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AIM: The aim of this study is to evaluate the association between urinary megalin, renal function, blood pressure, lipid profile, vitamin D and glycemic control in patients with type 2 diabetes mellitus (T2DM). METHODS: . This was a cross-sectional study which recruited 209 patients with T2DM. Urinary megalin was positively associated with systolic blood pressure (SBP) (r=0.218, p=0.04) but negatively with glomerular filtration rate (GFR) (r=-0.16, p=0.023). The levels of urinary albumin, triglycerides (TGs) and glycosylated hemoglobin (HbA1c) were higher in the "high-megalin" group, compared to those in "low-megalin" group. Moreover, there was a significant inverse association between vitamin D3 levels and megalin levels in urine (OR=0.281, p=0.047). CONCLUSION: Our study showed for the first time that megalin is associated with progression factors of diabetic nephropathy as well as vitamin D deficiency (Tab. 3, Fig. 1, Ref. 15).
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Nefropatías Diabéticas/orina , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/análisis , Albuminuria , Colecalciferol/orina , Estudios Transversales , Diabetes Mellitus Tipo 2/fisiopatología , Diabetes Mellitus Tipo 2/orina , Nefropatías Diabéticas/fisiopatología , Progresión de la Enfermedad , Tasa de Filtración Glomerular , Hemoglobina Glucada/orina , Humanos , Triglicéridos/orina , Deficiencia de Vitamina DAsunto(s)
Bioensayo/métodos , Glicerol/sangre , Tamizaje Masivo , Triglicéridos/orina , Adulto , Glicerol/orina , Humanos , MasculinoRESUMEN
Qushi Huayu Decoction (QHD), an important clinically proved herbal formula, has been reported to be effective in treating fatty liver induced by high-fat diet in rats. However, the mechanism of action has not been clarified at the metabolic level. In this study, a urinary metabolomic method based on gas chromatography-mass spectrometry (GC-MS) coupled with pattern recognition analysis was performed in three groups (control, model, and QHD group), to explore the effect of QHD on fatty liver and its mechanism of action. There was obvious separation between the model group and control group, and the QHD group showed a tendency of recovering to the control group in metabolic profiles. Twelve candidate biomarkers were identified and used to explore the possible mechanism. Then, a pathway analysis was performed using MetaboAnalyst 3.0 to illustrate the pathways of therapeutic action of QHD. QHD reversed the urinary metabolite abnormalities (tryptophan, uridine, and phenylalanine, etc.). Fatty liver might be prevented by QHD through regulating the dysfunctions of phenylalanine, tyrosine, and tryptophan biosynthesis, phenylalanine metabolism, and tryptophan metabolism. This work demonstrated that metabolomics might be helpful for understanding the mechanism of action of traditional Chinese medicine for future clinical evaluation.
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Medicamentos Herbarios Chinos/administración & dosificación , Hígado Graso/tratamiento farmacológico , Metabolómica , Triglicéridos/orina , Animales , Dieta Alta en Grasa/efectos adversos , Hígado Graso/etiología , Hígado Graso/metabolismo , Hígado Graso/orina , Cromatografía de Gases y Espectrometría de Masas , Humanos , Medicina Tradicional China , Metaboloma/genética , RatasRESUMEN
Triglycerides (TGs) are the major transporters of dietary fats throughout the bloodstream. Besides transporting fat, TGs also act as stored fat in adipose tissue, which is utilized during insufficient carbohydrates supply. TG level is below 150mg/dL in healthy persons. Elevated TGs level in blood over 500mg/dL is a biomarker for cardiovascular diseases, Alzheimer disease, pancreatitis and diabetes. Numerous methods are accessible for recognition of TGs, among them, most are cumbersome, time-consuming, require sample pre-treatment, high cost instrumental set-up and experienced personnel to operate. Biosensing approach overcomes these disadvantages, as these are highly specific, fast, easy, cost effective, and highly sensitive. This review article describes the classification, operating principles, merits and demerits of TG biosensors, specifically nanomaterials based biosensors. TG biosensors work ideally within 2.5-2700s, in pH range, 6.0-11.0, temperature 25-39.5°C and TG concentration range, 0.001-100mM, the detection limits being in the range, 0.1nM to 0.56mM, with working potential - 0.02 to 1.2V. These biosensors measured TG level in fruit juices, beverages, sera and urine samples and reused upto 200 times over a period of 7-240 days, while stored dry at 4°C. Future perspective for further improvement and commercialization of TG biosensors are discussed.
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Técnicas Biosensibles/métodos , Triglicéridos/análisis , Animales , Biomarcadores/análisis , Biomarcadores/sangre , Biomarcadores/orina , Técnicas Biosensibles/instrumentación , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Diseño de Equipo , Humanos , Nanoestructuras/química , Triglicéridos/sangre , Triglicéridos/orinaRESUMEN
A high-protein, low-carbohydrate diet has been regarded as a dietary intervention for weight loss in the obese population. We integrated metabolomics profiles and correlation-based network analysis to reveal the difference in metabolism under diets with different protein:carbohydrate ratios. Rats were fed a control diet (moderate-protein moderate-carbohydrate: MPMC; 20 % protein, 56 % carbohydrate) or HPLC diet (high-protein low-carbohydrate: 45 % protein, 30 % carbohydrate) for 6 weeks. The fat content was equal for both diets. HPLC feeding induced weight loss and reduced adipose weight and plasma triglyceride. Compared to the MPMC diet, HPLC significantly increased plasma α-tocopherol, pyruvate, 2-oxoisocaproate, and ß-hydroxybutyrate, and reduced linoleate, palmitate, α-glycerophosphate and pyroglutamic acid. The HPLC-associated urinary metabolite profile was signified with an increase in palmitate and stearate and a reduction of citrate, 2-ketoglutarate, malate, and pantothenate. Pathway analysis implicated a significant alteration of the TCA cycle in urine. Biomarker screening demonstrated that individual metabolites, including plasma urea, pyruvate, and urinary citrate, robustly distinguished the HPLC group from the MPMC group. Correlation-based network analysis enabled to demonstrate that the correlation of plasma metabolite was strengthened after the HPLC diet, while the energy-metabolism relatives 2-ketoglutarate and fumarate correlated positively with phenylalanine, methionine, and serine. The correlation network between plasma-urinary metabolites revealed a negative correlation of plasma valine with urinary ß-hydroxybutyrate in MPMC rats. In HPLC rats, plasma 2-oxoisocaproate negatively correlated with urinary pyruvate and glycine. This study using metabolomics analysis revealed the systemic metabolism in response to diet treatment and identified the significantly distinct profiles associated with a HPLC diet.
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Ácidos Carboxílicos , Proteínas en la Dieta/farmacología , Metaboloma/efectos de los fármacos , Triglicéridos , alfa-Tocoferol , Tejido Adiposo/metabolismo , Animales , Ácidos Carboxílicos/sangre , Ácidos Carboxílicos/orina , Masculino , Ratas , Ratas Wistar , Triglicéridos/sangre , Triglicéridos/orina , Pérdida de Peso/efectos de los fármacos , alfa-Tocoferol/sangre , alfa-Tocoferol/orinaRESUMEN
In this study, we investigated the clinical changes induced by a high fat diet (HFD) and caffeine consumption in a rat model. The mean body weight of the HFD with caffeine (HFDC)-fed rat was decreased compared to that of the HFD-fed rat without caffeine. The levels of cholesterol, triglycerides (TGs), and free fatty acid, as well as the size of adipose tissue altered by HFD, were improved by caffeine consumption. To investigate the metabolites that affected the change of the clinical factors, the urine and serum of rats fed a normal diet (ND), HFD, and HFDC were analyzed using ultra performance liquid chromatography quadruple time-of-flight mass spectrometry (UPLC-Q-TOF-MS), gas chromatography (GC-TOF-MS), and linear trap quadruple mass spectrometry (LTQ-XL-MS) combined with multivariate analysis. A total of 68 and 52 metabolites were found to be different in urine and serum, respectively. After being fed caffeine, some glucuronide-conjugated compounds, lysoPCs, CEs, DGs, TGs, taurine, and hippuric acid were altered compared to the HFD group. In this study, caffeine might potentially inhibit HFD-induced obesity and we suggest possible biomarker candidates using MS-based metabolite profiling.
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Cafeína/farmacología , Grasas de la Dieta/efectos adversos , Obesidad , Animales , Colesterol/sangre , Colesterol/orina , Grasas de la Dieta/farmacología , Ácidos Grasos/sangre , Ácidos Grasos/orina , Cromatografía de Gases y Espectrometría de Masas , Obesidad/sangre , Obesidad/inducido químicamente , Obesidad/tratamiento farmacológico , Obesidad/orina , Ratas , Triglicéridos/sangre , Triglicéridos/orinaRESUMEN
The clinical and laboratory findings in 78 patients with various forms of urolithiasis depending on the presence of primary hyperparathyroidism (PHPT) were analyzed. PHPT was diagnosed in 17 patients. Group "without PHPT" and group "with PHPT" differed significantly in terms of parathyroid hormone (PTH) level, serum calcium, phosphorus, chloride, alkaline phosphatase, calciuria and kaliuria. In patients with staghorn calculi, PHPT was diagnosed in 12.5%, and staghorn calculi in the presence of PHPT were identified in 17.7% of cases. Hypercalciuria in the group "with PHPT" was detected in 82.4% of patients (all 3 patients with staghorn calculi), and in the group "without PHPT"--in 18% of patients (2 of 21 patients with staghorn calculi). Hyperoxaluria was observed in 42.3% of patients "without PHPT" and in 35.3% of patients "with PHPT", in 36.8% of patients with simple stones and in 57.2%--with staghorn calculi. In 39% of patients "without PHPT", secondary hyperparathyroidism (SHPT) was diagnosed. SHPT prevalence was 28% in patients with staghorn calculi, and 45% in patients with simple stones. In 87.5% of patients with hypomagnesemia, staghorn calculi were observed. Significant relationship between magnesium and triglycerides (r(s) = -0.296; P = 0.041), and magnesium and high-density lipoproteins (r(s) = 0.339; P = 0.032) in all patients with urolithiasis were revealed. Thus, the study found no association between staghorn nephrolithiasis and PHPT. Elevated PTH levels usually indicate SHPT rather than PHPT. In hypocalcemia, there was more strong association between PTH and calcium, in normocalcaemia--between PTH and magnesium.
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Hiperparatiroidismo/sangre , Hiperparatiroidismo/orina , Urolitiasis/sangre , Urolitiasis/orina , Adulto , Anciano , Anciano de 80 o más Años , Calcio/sangre , Calcio/orina , Cloruros/sangre , Cloruros/orina , Femenino , Humanos , Hiperparatiroidismo/complicaciones , Hiperparatiroidismo/diagnóstico , Lipoproteínas HDL/sangre , Lipoproteínas HDL/orina , Magnesio/sangre , Magnesio/orina , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Hormona Paratiroidea/orina , Fósforo/sangre , Fósforo/orina , Triglicéridos/sangre , Triglicéridos/orina , Urolitiasis/complicaciones , Urolitiasis/diagnósticoRESUMEN
CONTEXT: High plasma triglycerides (TG) have been shown to be independent and better predictors of cardiovascular disease than low-density lipoprotein (LDL) cholesterol in women. This may be due to gender differences in very-low-density lipoprotein 1 (VLDL(1))- and VLDL(2)-TG and fatty acid kinetics. OBJECTIVE: Our objective was to investigate whether there are differences in VLDL(1)- and VLDL(2)-TG and fatty acid kinetics in obese men and postmenopausal women, a high risk group for cardiovascular disease. RESEARCH DESIGN AND METHODS: Stable isotopes techniques were used to measure fasting palmitate rate of appearance, metabolic clearance rate, oxidation rate, and nonoxidative disposal rate, VLDL(1)-TG and VLDL(2)-TG fractional catabolic rate (FCR) and production rate (PR). Whole-body fat distribution was measured by magnetic resonance imaging. PARTICIPANTS: Participants included 10 postmenopausal obese women and eight obese men matched for age, body mass index, and fasting plasma TG. RESULTS: The women had lower visceral fat and higher sc fat than the men (P < 0.001 and P < 0.002). Palmitate rate of appearance, metabolic clearance rate, nonoxidative disposal rate, and oxidation rate corrected for resting energy expenditure were greater in the women than the men (all P < 0.03). VLDL(2)-TG PR corrected for fat-free mass was higher in the women (P < 0.001). VLDL(2)-TG and VLDL(2)-cholesterol pools were higher in the women (P < 0.001 and P < 0.008). VLDL(1)-TG FCR and PR and VLDL(2)-TG FCR were not different between genders. CONCLUSION: Fatty acid and VLDL(2)-TG flux is higher in postmenopausal obese women than in obese men matched for fasting plasma TG levels.
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Ácidos Grasos/metabolismo , Lipoproteínas VLDL/metabolismo , Obesidad/metabolismo , Posmenopausia/metabolismo , Caracteres Sexuales , Triglicéridos/metabolismo , Composición Corporal/fisiología , Estudios de Casos y Controles , Metabolismo Energético/fisiología , Ácidos Grasos/sangre , Ácidos Grasos/orina , Femenino , Humanos , Cinética , Lipoproteínas VLDL/sangre , Lipoproteínas VLDL/orina , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/orina , Posmenopausia/sangre , Posmenopausia/orina , Triglicéridos/sangre , Triglicéridos/orinaRESUMEN
AIMS: Protein glycation leading to advanced glycation-endproducts (AGE) is enhanced in diabetes by increased blood glucose and collateral endogenous production of reactive α-dicarbonyls. Among AGE precursors, methylglyoxal (MG) is considered as one of the key intermediates. We hypothesized it to be a common product of both carbonyl and oxidative stress, and investigated its biogenesis in relation to glycemic and lipid status in diabetic patients. METHODS: Serum and urine MG-adducts were measured by competitive immunofluorometric assay in 83 diabetic and 20 healthy subjects. KEY FINDINGS: A significant association of MG-adducts serum level with LDL (r=0.31;p=0.003) was observed. A correlation between LDL-c, HDL-C and PPG as independent variables and serum MG-adducts as a dependent variable was found (p<0.014) using multiple stepwise regression, whereas urine albumin/creatinine ratio was independently associated with urine MG-adducts. LDL cut-off >3.0mmol/l discriminated patients with higher serum MG-adducts (p=0.0052), although there was no between-subgroup difference in glycemic control. Patients on statin therapy had a lower MG-adduct level. The positive relationship between LDL-c and MG-adducts (r=0.38;p=0.042) was noted in patients free of statin treatment, whereas an inverse tendency was found in the statin-treated subgroup. SIGNIFICANCE: Significant relationship between LDL and MG-adduct production, as well as tight correlation between triglycerides and urinary MG-adduct excretion suggest that the lipoxidation and glyceraldehyde-3-phosphate route, along with the glycolytic pathway, might be an important source of MG generation. The glycotoxin methylglyoxal seems to be a common factor linking hyperglycemia and intensive lipolysis, two dominant metabolic changes in diabetes.
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LDL-Colesterol/sangre , LDL-Colesterol/orina , Diabetes Mellitus/sangre , Diabetes Mellitus/orina , Piruvaldehído/sangre , Piruvaldehído/orina , Triglicéridos/sangre , Triglicéridos/orina , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/orina , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/orina , Productos Finales de Glicación Avanzada/sangre , Productos Finales de Glicación Avanzada/orina , Humanos , Hiperlipidemias/sangre , Hiperlipidemias/orina , Persona de Mediana EdadAsunto(s)
Quilo , Quilomicrones/orina , Adulto , Colesterol/orina , Femenino , Humanos , Lipoproteínas/orina , Triglicéridos/orina , Orina/químicaRESUMEN
A 27 year old patient presented with a sudden acute illness showing right flank pain, milky urine, nephrotic range proteinuria, erythrocyturia and leukocyturia in the urinary sediment with a negative leukocyte test stick. The proof of a pronounced hypertriglyceriduria led to the diagnosis of Chyluria. The lymphangiogram confirmed the presence of a retroperitoneal lymphatic dysplasia with evidence of communication with the right renal pelvis on the CT-lymphogram. Chyluria is generally the result of parasitic infection and is extremely rare in Europe. In the presence of symptoms including milky urine, proteinuria and leukocyturia in the urinary sediment and a negative urine leukocyte stick test and absence of infectious signs, chyluria must be suspected. The diagnosis should be substantiated through proof of hypertriglyceriduria and confirmed by lymphangiography.
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Quilo , Enfermedades Linfáticas/complicaciones , Síndrome Nefrótico/etiología , Enfermedad Aguda , Adulto , Femenino , Humanos , Hipercolesterolemia/complicaciones , Enfermedades Linfáticas/diagnóstico , Enfermedades Linfáticas/diagnóstico por imagen , Enfermedades Linfáticas/cirugía , Linfografía , Síndrome Nefrótico/orina , Dolor/etiología , Proteinuria/etiología , Tomografía Computarizada por Rayos X , Triglicéridos/orina , OrinaRESUMEN
Dicarboxylic acids (DA) are alternate lipid substrates recently proposed in parenteral nutrition. Two new derivatives of DA, a triglyceride of sebacic (TGC10) and one of dodecanedioic (TGC12) acid have been synthesised in order to reduce the amount of sodium given with the unesterified forms. The present paper describes a rapid and direct high-performance liquid chromatographic method (HPLC) for the analysis of these substances in both plasma and urine. Thirty-six male Wistar rats were rapidly injected with 64 mg of TGC10 or 53 mg of TGC12. The triglycerides and their products of hydrolysis were measured in plasma samples taken at different times. For the dose of 500 ng the intra-assay variations ranged from 6. 80+/-0.35% for TGC10 to 18.6+/-3.20% for TGC12 and the inter-assay variations were from 4.44+/-2.21% for TGC10 to 15.0+/-6.72% for TGC12. The detection limit for both triglycerides was 5 ng. This rapid and direct HPLC method could have practical implications in monitoring the concentration of both triglycerides and free forms of DA in biological samples of patients who might benefit from the administration of these substances during parenteral nutrition regimens.
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Caprilatos , Cromatografía Líquida de Alta Presión/métodos , Ácidos Dicarboxílicos/análisis , Triglicéridos/análisis , Animales , Calibración , Ácidos Decanoicos/análisis , Ácidos Dicarboxílicos/sangre , Ácidos Dicarboxílicos/orina , Masculino , Ratas , Ratas Wistar , Sensibilidad y Especificidad , Triglicéridos/sangre , Triglicéridos/orinaRESUMEN
The kinetics of the triglyceride of dodecanedioic acid (TGDA) has been investigated in 30 male Wistar rats after a rapid intravenous bolus injection. TGDA and its product of hydrolysis, nonesterified dodecanedioic acid (NEDA), were measured in plasma samples taken at different times using an improved high-performance liquid chromatographic method. The 24-h urinary excretion of TGDA was 1.54 +/- 0.37 micromol, corresponding to approximately 0.67% of the administered amount. Several kinetics models were considered, including central and peripheral compartments for the triglyceride and the free forms and expressing transports between compartments with combinations of linear, carrier-limited, or time-varying mechanisms. The parameter estimates of the kinetics of TGDA and of NEDA were finally obtained using a three-compartment model in which the transfer of TGDA to NEDA was assumed to be linear, through a peripheral compartment, and the tissue uptake of NEDA was assumed to be carrier limited. TGDA had a large volume of distribution ( approximately 0.5 l/kg body wt) with a fast disappearance rate from plasma (0.42 min-1), whereas NEDA had a very small volume of distribution ( approximately 0.04 l/kg body wt) and a tissue uptake with maximal transport rate of 0.636 mM/min. In conclusion, this first study on the triglyceride form of dodecanedioic acid indicates that it is rapidly hydrolyzed and that both triglyceride and nonesterified forms are excreted in the urine to a very low extent. The tissue uptake rate of NEDA is consistent with the possibility of achieving substantial energy delivery, should it be added to parenteral nutrition formulations. Furthermore, the amount of sodium administered with the triglyceride form is one-half of that necessary with the free diacid.
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Ácidos Dicarboxílicos/metabolismo , Triglicéridos/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Esterificación , Hidrólisis , Cinética , Masculino , Modelos Biológicos , Ratas , Ratas Wistar , Triglicéridos/orinaRESUMEN
The presence of lipids in postprandial urine was assessed in 116 patients with a history of filariasis and 70 normal individuals using a biochemical autoanalyzer. Urinary triglycerides (TGs) ranging from 10 to 1955 mg/dl were detected in 13 individuals with a history of chyluria, including 3 with TG levels ranging from 233 to 1955 mg/dl and cholesterol levels of 6-35 mg/dl. Three patients who had a filarial history but without chyluria were also found to have urinary TGs (13-15 mg/dl) without detectable cholesterol. Neither TGs nor cholesterol were detected in the urine of normal individuals. Fluctuations in postprandial urine lipid contents were measured by time course determinations of urinary TG and cholesterol in 17 patients with filariasis and a history of chyluria, 16 patients with filariasis and hydrocele and 16 normal individuals. The level of urine lipid excretion was found to increase within 1-4 h postprandially, with urinary TG levels ranging between 7.8 and 1284 mg/h in eight patients and urinary cholesterol levels between 1.2 and 138 mg/h in seven patients with a history of chyluria. To evaluate the origin of the urine lipids in hematochyluria, fish oil containing 360 mg eicosapentaenoic acid (EPA) and 240 mg docosahexaenoic acid (DHA) was prescribed to a patient with hematochyluria. The excretion of EPA and DHA in urine was increased postprandially in the patient, similar to the elevation of urinary TG and cholesterol. The profile of fatty acids from urine samples showed it was of dietary origin. Our results suggest that postprandial urine lipids, especially TG, might be used as markers for the clinical evaluation of chyluria.
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Quilo/metabolismo , Filariasis/diagnóstico , Filariasis/orina , Triglicéridos/orina , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Ácidos Docosahexaenoicos/farmacocinética , Ácido Eicosapentaenoico/farmacocinética , Femenino , Aceites de Pescado/farmacocinética , Hematuria/orina , Humanos , Masculino , Persona de Mediana Edad , Periodo Posprandial , Reproducibilidad de los Resultados , OrinaRESUMEN
Three new metabolites of medium-chain fatty acid oxidation, 3-, 6- and 7-hydroxyoctanoyl beta-D-glucuronide, were identified in the urine of six infants who were fed a diet enriched in medium-chain triglycerides (MCT). Glucuronides were extracted from the urine by organic solvent extraction with ethyl acetate and by solid-phase extraction on Sep-Pak C18 cartridges. The compounds of interest were also purified from the organic solvent extract by preparative one-dimensional thin-layer chromatography. Cleavage of the glucuronides was achieved by either alkaline hydrolysis or enzymatic hydrolysis with beta-D-glucuronidase. The analyses of the trimethylsilylated derivatives were performed both by gas chromatography with flame ionization detection (GC/FID) and by gas chromatography/mass spectrometry (GC/MS). The structure of the hydroxyoctanoic acids was proved by comparison of their mass spectra with those of reference substances. Authentic 6-hydroxyoctanoic acid was synthesized. The presence of 6-hydroxyoctanoyl glucuronide shows that in addition to beta-oxidation, omega-oxidation and (omega-1)-hydroxylation, medium-chain fatty acids can be oxidized at the omega-2 position. The conjugation of medium-chain hydroxy-monocarboxylic acids with glucuronic acid has not been described in humans before.
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Caprilatos/orina , Triglicéridos/orina , Cromatografía en Capa Delgada , Dieta , Ionización de Llama , Cromatografía de Gases y Espectrometría de Masas , Glucuronatos/orina , Humanos , Hidrólisis , Lactante , Oxidación-ReducciónRESUMEN
Two experiments were conducted to determine the effects of supplementary choline and/or pantothenate on the carnitine and lipid status of free-living humans. Analyses of carnitine and cholesterol fractions, triacylglycerols, and creatinine were determined in serum and/or urine. In experiment 1, adults receiving 13.5 mmol choline plus 1.4 mmol pantothenate/d had a significant decline in urinary carnitine excretion and renal clearance with nonesterfied carnitine (NEC) declining the most dramatically, 84%. Additionally, serum NEC and total carnitine concentrations decreased significantly. No changes were observed in any of the serum lipids examined. In experiment 2, subjects took 0.20 mmol and 0.02 mmol/kg choline or pantothenate, respectively. Choline, but not pantothenate, supplementation significantly decreased urinary carnitine excretion, renal clearance, and fractional clearance of NEC. We conclude that supplementary choline maintained serum carnitine concentrations by conserving urinary carnitine. Moreover, these observations merit additional investigation to determine metabolic and functional consequences of choline and carnitine interactions in humans.
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Carnitina/orina , Colina/farmacología , Adulto , Carnitina/sangre , Colesterol/sangre , Colesterol/orina , Colina/administración & dosificación , Femenino , Alimentos Fortificados , Humanos , Riñón/fisiología , Masculino , Persona de Mediana Edad , Ácido Pantoténico/farmacología , Triglicéridos/sangre , Triglicéridos/orinaRESUMEN
OBJECTIVE: To test the hypothesis that patients with calcific kidney stones (stone formers) excrete more lipids and cell membranes in their urine than do normal individuals. PATIENTS, SUBJECTS AND METHODS: Lipids were isolated from the urine of patients with calcific stones (four women and six men, age range 28-69 years) and from normal subjects (three men and three women, age range 31-54 years). Different phospholipids, neutral lipids and glycolipids were identified using thin layer chromatography and individual lipids were characterized by several assays after scraping the spots from the plates, or by densitometry. RESULTS: Stone formers excreted more lipids and acidic phospholipids than did normal individuals; the urinary excretion of glycolipid, cholesterol and cholesterol esters was also increased. CONCLUSIONS: The greater excretion of lipids may reflect the increased turnover of cells in the tubular epithelium and sloughing of cells into the urine in response to a challenge by oxalate and calcium oxalate crystals. Acidic phospholipids from cellular membranes of the sloughed epithelial cells may be involved in crystal nucleation and retention within the kidneys and thus the initial development of stone nidus and the continued growth thereafter.
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Glucolípidos/orina , Cálculos Renales/orina , Fosfolípidos/orina , Adulto , Anciano , Colesterol/orina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Triglicéridos/orinaRESUMEN
A continuous system coupled to a gas-liquid chromatograph was used for the sequential determination of triglycerides and free fatty acids in serum and urine. The module provides compositional information and hence more detailed information on lipid metabolism changes in patients suffering metabolic disorders. Lipids in biological samples are manually extracted in methanol-n-hexane and introduced into the flow system; free fatty acids are then separated by retention on an ion-exchange resin and triglycerides (not retained) are transesterified with acetyl chloride in methanol. The resulting methyl esters are continuously injected into the gas chromatograph and determined by using a flame ionization detector. In a second step, retained free fatty acids are eluted and derivatized (also with acetyl chloride in methanol) and subsequently determined similarly as the triglycerides. The proposed method was applied to the determination of triglycerides in a lipid control serum; free fatty acids were determined in a human pool serum by the proposed method and compared with the volumetric method used in clinical practice. The results obtained in both instances showed good agreement between the results provided for triglycerides and free fatty acids. The proposed method was also applied to urine samples; a parallel recovery study was also made in order to assess the performance of the method.