Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020500 (hyperoxaluria)
 912 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

According to the two-mutation model of neuroblastoma several investigations were performed in order to find the gene carrier in a family with familial neuroblastoma. The results of these former studies are as follows: 1. Neither chromosomal analyses of the peripheral blood nor the examinations of catecholamines nor of cystathionine in the urine could mark the first step to neuroblastoma. 2. Since cystathioniuria was not only seen in blood-relations but also in relatives by marriage and since vitamin B6 deficiency was revealed, cystathioninuria was interpreted as secondary to vitamin B6 deficiency. In this study the normal values of cystathioninuria and vitamin B6 supply were examined. Furthermore the effect of oral vitamin B6 loading on cystathioninuria and oxaluria in familial neuroblastoma was investigated and the vitamin B6 supply in the neighbours of the family was analysed. The results permitted the following conclusions: 1. In 46 of 58 children and adults cystathioninuria was found in an immeasurable range by column chromatography. Only in 12 persons it could be measured quantitatively. With the exception of 6 explanable elevations no value exceeded 20 mumol/24 hr. These results show that the acceptance of the limiting value of 20 mumol/24 hr for increased cystathioninuria is justified. 2. Vitamine B6 deficiency was found in two of 7 patients. In one child this could be explained by the underlying disease. This finding supports the suggestion that vitamine B6 deficiency can relative frequently observed. 3. The examinations of cystathioninuria and oxaluria before and after loading with vitamine B6 showed different results. Whereas oxaluria decreased after loading cystathioninuria was not surely influenced. 4. The neighbours of the members with familial neuroblastoma showed mostly a reduced vitamine B6 supply. This fact could be an indication of exogenous reason of vitamine B6 deficiency in familial neuroblastoma.
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PMID:[Biochemical studies on familial neuroblastoma]. 64 89

Chronic vitamin B6 deficiency in male rats, 1, 2 and 3 months of age, led to increases in the activities of liver glycolate oxidase and kidney glycolate dehydrogenase as compared to pair-fed controls. Lactate dehydrogenase activity either decreased or showed no change in all three age groups. It is postulated that hyperoxaluria observed in vitamin B6 deficiency is due to two different pathways operative in the liver and kidney separately. A general increase seen in the enzyme activities of livers and kidneys of B6-deficient and pair-fed rats was age related.
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PMID:Vitamin B6 deficiency as related to oxalate-synthesizing enzymes in growing rats. 705 48

Observed loss in body weight gain, increased lipid peroxidation reaction, decreased concentrations of antioxidants, ascorbic acid, alpha-tocopherol and reduced glutathione and antioxidant enzymes, glutathione peroxidase and catalase and increased concentration of hydroperoxides and hydroxyl radicals in vitamin B6 deficient rat liver [J Nutri Biochem, 2 (1991) 245] and kidney [Biochem International, 21 (1991) 599] were nearly normalized on feeding with vitamin E or methionine. Accumulation of oxalate and calcium during vitamin B6 deficiency was abolished by feeding vitamin E or methionine. Calcium oxalate deposition observed in vitamin B6 deficient kidney was completely prevented when fed along with vitamin E or methionine. However the hyperoxaluria and hypercalciuria persisted even after feeding with vitamin E or methionine.
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PMID:Restoration of tissue antioxidants and prevention of renal stone deposition in vitamin B6 deficient rats fed with vitamin E or methionine. 811 61

Vitamin B6 metabolites and their potential correlates to urinary oxalate excretion in idiopathic calcium stone formers (ICSF) compared with healthy subjects were investigated. This clinical study was performed in a population of male ICSF with (Hyperoxalurics, n=55) or without hyperoxaluria (Normooxalurics, n=57) as well as in 100 healthy male control subjects. Pyridoxal 5'-phosphate serum concentration (S-pyridoxal 5'P) and 24-h urinary excretion of 4-pyridoxic acid (U-4pyridoxic acid) were measured using HPLC; 24-h urinary excretion of oxalate (U-oxalate) was measured concurrently. A subgroup of subjects (40 Hyperoxalurics, 15 Normooxalurics and 50 controls) underwent the same measurements before and after 7-day pyridoxine loading per os (pyridoxine hydrochloride, 300 mg/d). Under usual conditions, U-4pyridoxic acid was similar in the three groups, whereas mean S-pyridoxal 5'P was significantly lower ( p<0.0001) in the Hyperoxalurics (59.6+/-21.2 nmol/L) and in the Normooxalurics (64.9+/-19.7 nmol/L) than in the controls (86.0+/-31.0 nmol/L). No correlation could be found between U-oxalate and U-4pyridoxic acid or S-pyridoxal 5'P. After B6 loading, S-pyridoxal 5'P was still significantly lower in the Hyperoxalurics (415+/-180 nmol/L, p<0.001) and in the Normooxalurics (429+/-115 nmol/L, p=0.036) than in the controls (546+/-180 nmol/L), although there was no difference between groups for U-4pyridoxic acid. No correlation in any group could be found between changes in U-oxalate and changes in U-4pyridoxic acid or S-pyridoxal 5'P. Although there is no vitamin B6 deficiency in ICSF with or without hyperoxaluria, these patients, on average, have lower levels of S-pyridoxal 5'P than healthy subjects. However, this slight decrease does not seem to account for idiopathic hyperoxaluria.
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PMID:Vitamin B6 metabolites in idiopathic calcium stone formers: no evidence for a link to hyperoxaluria. 1462 6

We examined the effect of vitamin B6 deficiency on glyoxylate metabolism and hepatic alanine: glyoxylate aminotransferase (AGT) activity in rats with normal or high glyoxylate intake. Male rats were divided into four groups: a control group, a vitamin B6-free diet group, a glyoxylate water group, and a vitamin B6-free diet + glyoxylate water group. Each group was given special diet (control or vitamin B6-deficient diet) and drinking water (plain or 0.5% glyoxylate water) for 4 weeks, after which biochemical parameters and hepatic AGT mRNA level were measured. Compared with control rats, the urinary oxalate/creatinine ratio was higher in each of the other 3 groups. The urinary glycolate/creatinine ratio was also higher in the vitamin B6-free diet group and the vitamin B6-free diet + glyoxylate water group than the control group, while the urinary glycine/creatinine and citrate/creatinine ratio was lower in both groups. The hepatic AGT mRNA level was reduced in the vitamin B6-free diet group, but was increased in the glyoxylate water group than the control group. These results suggest that vitamin B6 is necessary for glyoxylate metabolism as a coenzyme of AGT. Especially in the presence of a high glyoxylate intake, vitamin B6 deficiency leads to severe hyperoxaluria and hypocituria.
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PMID:Effect of vitamin B6 deficiency on glyoxylate metabolism in rats with or without glyoxylate overload. 1684 54

The prevalence of idiopathic nephrolithiasis is increasing in rich countries. Dietary manipulation could contribute to the prevention of both its first appearance and the recurrence of the disease. The target of dietary treatment is to decrease the "urinary lithogenic risk factors" such as low urine volume, hypercalciuria, hyperoxaluria, hyperuricosuria, hyperphosphaturia, hypocitraturia, hypomagnesuria and excessively alkaline or acid urinary pH. Due to the lack of randomized controlled trials focused on this problem, there is not ample evidence to confidently recommend dietary changes. Despite this, numerous recent and past experiences support modification of diet as having a primary role in the prevention of nephrolithiasis. In particular, it is recommended to limit animal protein and salt intake, to consume milk and derivatives in amounts corresponding to calcium intake of about 1200 mg/day and to assume fiber (40 g/day), vegetables and fruit daily avoiding foods with high oxalate content. Furthermore, vitamin C intake not exceeding 1500 mg/day plays a protective role as well as avoiding vitamin B6 deficiency and abstaining, if possible, from vitamin D supplements. Lastly, it is recommended to drink enough water to bring the urinary volume up to at least 2 L/day and, as much as possible, to use fresh or frozen products rather than prepacked or precooked foods which are often too rich in sodium chloride.
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PMID:Dietary treatment of nephrolithiasis. 2246 Sep 96