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The Journal of Nutrition Feb 1991Stable-isotopic methods were employed to evaluate the utilization of dietary pyridoxine-5'-beta-D-glucoside (PN-glucoside), a major form of vitamin B-6 in plant-derived... (Clinical Trial)
Clinical Trial
Stable-isotopic methods were employed to evaluate the utilization of dietary pyridoxine-5'-beta-D-glucoside (PN-glucoside), a major form of vitamin B-6 in plant-derived foods, as a source of available vitamin B-6 for adult men (20-35 y old, n = 5). Deuterium-labeled forms of free pyridoxine (PN) and PN-glucoside were compared using the urinary excretion of labeled forms of the vitamin B-6 metabolite 4-pyridoxic acid as the main index of absorption and metabolism. When comparing orally administered, isotopically labeled PN and PN-glucoside in separate groups of subjects, similar bioavailability was observed although within-group variability was high. A dual-label study designed to examine the bioavailability of these compounds when administered simultaneously indicated that the utilization of deuterated PN-glucoside was 58 +/- 13% (mean +/- SEM) relative to that of deuterated PN. PN-glucoside was detected in all urine samples, which provided additional evidence of incomplete metabolic utilization. In contrast, intravenously administered PN-glucoside underwent approximately half the metabolic utilization of oral PN-glucoside. These studies indicate that the bioavailability of dietary PN-glucoside, although incomplete, is substantially greater in humans than previously found in rats. In addition, the difference between oral and intravenous routes suggests a role of beta-glucosidase(s) of the intestinal mucosa, microflora, or both in the release of free PN from dietary PN-glucoside.
Topics: Administration, Oral; Adult; Biological Availability; Gas Chromatography-Mass Spectrometry; Glucosides; Humans; Infusions, Intravenous; Male; Mass Spectrometry; Nutritional Status; Pyridoxine; Random Allocation
PubMed: 1995788
DOI: 10.1093/jn/121.2.177 -
The Journal of Nutrition Apr 1992A major form of vitamin B-6 in plant-derived foods is pyridoxine-5'-beta-D-glucoside. Previous studies have shown that pyridoxine-5'-beta-D-glucoside is poorly available...
A major form of vitamin B-6 in plant-derived foods is pyridoxine-5'-beta-D-glucoside. Previous studies have shown that pyridoxine-5'-beta-D-glucoside is poorly available as a source of vitamin B-6 in rats and is partially utilized in humans. This research was conducted to determine whether unlabeled pyridoxine-5'-beta-D-glucoside affects the metabolic utilization of simultaneously administered isotopically labeled pyridoxine in rats. Three groups of rats (n = 6) were administered a single oral dose of 0, 36 or 72 nmol of unlabeled pyridoxine-5'-beta-D-glucoside along with 166.5 MBq (240 nmol) of [14C]pyridoxine. Twenty-four hours after administration of the dose the rats were killed, and the isotopic distribution of vitamin B-6 metabolites in liver and urine was determined. Urinary 14C and hepatic 14C-labeled pyridoxine phosphate and pyridoxal phosphate were directly related to pyridoxine-5'-beta-D-glucoside dose. Hepatic 14C, 14C-labeled pyridoxal, pyridoxine and pyridoxamine, and the concentration of urinary [14C]4-pyridoxic acid, relative total urinary 14C, were inversely proportional to the dose of pyridoxine-5'-beta-D-glucoside. These results provide evidence that pyridoxine-5'-beta-D-glucoside quantitatively alters the metabolism and in vivo retention of [14C]pyridoxine and that pyridoxine-5'-beta-D-glucoside may retard the utilization of nonglycosylated forms of vitamin B-6.
Topics: Administration, Oral; Animals; Biological Availability; Chromatography, High Pressure Liquid; Glucosides; Liver; Male; Pyridoxine; Rats; Rats, Inbred Strains
PubMed: 1552357
DOI: 10.1093/jn/122.4.1029 -
Developmental Medicine and Child... Jun 1985A case of pyridoxine-dependent seizures is reported. Administration of pyridoxine to an infant after a long period of convulsions was followed by acute hypotonia. Other...
A case of pyridoxine-dependent seizures is reported. Administration of pyridoxine to an infant after a long period of convulsions was followed by acute hypotonia. Other cases have been reported in the literature, in one of which assisted ventilation was required. A possible mechanism for this alarming outcome is discussed, and it is suggested that resuscitation facilities should be quickly available during such trials.
Topics: Electroencephalography; Evoked Potentials; Humans; Infant, Newborn; Male; Muscle Hypotonia; Pyridoxine; Spasms, Infantile
PubMed: 4018433
DOI: 10.1111/j.1469-8749.1985.tb04551.x -
Brain Research Bulletin Sep 2002
Topics: Epilepsy; Humans; Pyridoxal Phosphate; Pyridoxine
PubMed: 12372554
DOI: 10.1016/s0361-9230(02)00802-x -
Acta Paediatrica (Oslo, Norway : 1992) 2002Pyridoxine-dependent seizures are rare in newborn infants, although recent data suggest that the prevalence probably is underestimated. In all newborn infants with...
UNLABELLED
Pyridoxine-dependent seizures are rare in newborn infants, although recent data suggest that the prevalence probably is underestimated. In all newborn infants with recurrent epileptic seizures the general recommendation is to administer pyridoxine and simultaneously record an electroencephalogram (EEG).
CONCLUSION
One infant with pyridoxine-responsive seizures and another with pyridoxine-dependent seizures had different electroclinical responses on amplitude-integrated EEG monitoring (aEEG) when pyridoxine was administered.
Topics: Brain; Electroencephalography; Epilepsy; Humans; Infant, Newborn; Male; Pyridoxine
PubMed: 12222726
DOI: 10.1080/080352502760148748 -
The New England Journal of Medicine Aug 1983
Topics: Humans; Metabolism, Inborn Errors; Nutritional Requirements; Orthomolecular Therapy; Peripheral Nervous System Diseases; Pyridoxine; Sensation; Substance-Related Disorders; Syndrome; Vitamin B 6 Deficiency; Vitamins
PubMed: 6308448
DOI: 10.1056/NEJM198308253090808 -
Annals of Internal Medicine May 1986
Topics: Adult; Humans; Hydrazines; Male; Peripheral Nervous System Diseases; Pyridoxine
PubMed: 3008620
DOI: 10.7326/0003-4819-104-5-728_2 -
The British Journal of Clinical Practice Nov 1988We present a survey summarising the retrospective reports of the therapeutic effect of pyridoxine (vitamin B6) in 630 women suffering from premenstrual syndrome (PMS)...
We present a survey summarising the retrospective reports of the therapeutic effect of pyridoxine (vitamin B6) in 630 women suffering from premenstrual syndrome (PMS) who attended a PMS clinic during the period 1976-1983. The daily doses of pyridoxine hydrochloride varied from 40 to 100 mg early in the study and from 120 to 200 mg in the later period of the investigations. The response to treatment was recorded as good (no significant residual complaints) in 40 per cent or more of patients taking 100-150 mg pyridoxine daily and in 60 per cent of patients treated with 160-200 mg daily. Together with partial response (useful benefit but still some significant complaints), the positive effect of the treatment increased to 65-68 per cent and 70-88 per cent respectively. No symptoms consistent with a diagnosis of peripheral neuropathy were reported.
Topics: Adolescent; Adult; Drug Evaluation; Drug Therapy, Combination; Female; Humans; Middle Aged; Premenstrual Syndrome; Pyridoxine; Retrospective Studies
PubMed: 3256334
DOI: No ID Found -
Revista de NeurologiaWe described the electroclinical features, evolution and family history of two patients with definitive diagnosis of pyridoxine dependency.
OBJECTIVE
We described the electroclinical features, evolution and family history of two patients with definitive diagnosis of pyridoxine dependency.
CASE REPORTS
The first patient is a 15-month-old girl who at 1 month of age started with seizures and irritability. At two months of age, pyridoxine was prescribed with a good control of seizures. At five months of age withdrawal response provoked 7 days after seizures recurrence. Pyridoxine was reintroduced and seizures disappeared. Her sister, at two months of age, started with refractory seizures. This sister also had mental retardation and at four years, she died. Her brother, 16 years old, presents mental retardation, refractory epilepsy and progressive motor and cognitive impairment. At 3 months of age, he started with seizures and at 15 years of age, pyridoxine was prescribed with a significative improvement the number of seizures and a better visual connection. The second patient is a 4-month-old girl who started with clonic seizures at 3 days of age and she had a good response to pyridoxine. Withdrawal response provoked seizure recurrence at 48 hours. Pyridoxine was introduced immediately with total control of seizures. She had two cousins with seizures who died at 3 months and 3 years of age respectively.
CONCLUSION
When dealing with an infant with refractory seizures which start in the first two years of life and without etiology, we should consider the diagnosis of pyridoxine dependency. Early diagnosis and treatment with pyridoxine is crucial to avoid high risk morbidity and mortality. All infants in the two first years of life with refractory seizures without etiology must be prescribed oral pyridoxine (50-200 mg per day).
Topics: Female; Humans; Infant; Pyridoxine; Seizures; Time Factors
PubMed: 14730491
DOI: No ID Found -
The Journal of Nutrition Nov 1996Uptake and metabolism of pyridoxine-4'-alpha-D-glucoside and pyridoxine-5'-alpha-D-glucoside by freshly isolated rat liver cells were studied using the membrane...
Uptake and metabolism of pyridoxine-4'-alpha-D-glucoside and pyridoxine-5'-alpha-D-glucoside by freshly isolated rat liver cells were studied using the membrane filtration method. The presence of the pyridoxine-alpha-glucosides at either 0.5 or 5.0 micromol/L had no inhibitory effect on the uptake of pyridoxine (0.5 micromol/L) by hepatocytes. The amount of pyridoxine-alpha-glucoside transported into the cells was only 10-12% of that of pyridoxine. The initial rates of uptake of the pyridoxine-alpha-glucosides were linear with concentrations up to 50 micromol/L. On entry into the cells, 78% of pyridoxine-5'-alpha-glucoside and 15% of the pyridoxine-4'-alpha-glucoside were hydrolyzed at the end of 60 min. Because pyridoxine-5'-alpha-glucoside is hydrolyzed readily and does not interfere with the transport of pyridoxine, the glucoside, if present in animal- or plant-derived foods, may be available as a source of vitamin B-6.
Topics: Animals; Cells, Cultured; Chromatography, High Pressure Liquid; Glucosides; Liver; Male; Pyridoxine; Rats; Rats, Sprague-Dawley; Time Factors; Tritium
PubMed: 8914963
DOI: 10.1093/jn/126.11.2899