1548: Impact of Ascorbic Acid on Cystine Stone Formation - Evaluation in the Animal Model

2006 ◽  
Vol 175 (4S) ◽  
pp. 499-500
Author(s):  
Sreedhar Sagi ◽  
Yanwei Cao ◽  
Axel Haecker ◽  
Peter Aiken ◽  
Maurice S. Michel ◽  
...  
2006 ◽  
Vol 5 (2) ◽  
pp. 33
Author(s):  
S. Sagi ◽  
Y. Cao ◽  
A. Haecker ◽  
M.S. Michel ◽  
P. Alken ◽  
...  

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 528
Author(s):  
Roswitha Siener ◽  
Norman Bitterlich ◽  
Hubert Birwé ◽  
Albrecht Hesse

Despite the importance of dietary management of cystinuria, data on the contribution of diet to urinary risk factors for cystine stone formation are limited. Studies on the physiological effects of diet on urinary cystine and cysteine excretion are lacking. Accordingly, 10 healthy men received three standardized diets for a period of five days each and collected daily 24 h urine. The Western-type diet (WD; 95 g/day protein) corresponded to usual dietary habits, whereas the mixed diet (MD; 65 g/day protein) and lacto-ovo-vegetarian diet (VD; 65 g/day protein) were calculated according to dietary reference intakes. With intake of the VD, urinary cystine and cysteine excretion decreased by 22 and 15%, respectively, compared to the WD, although the differences were not statistically significant. Urine pH was significantly highest on the VD. Regression analysis showed that urinary phosphate was significantly associated with cystine excretion, while urinary sulfate was a predictor of cysteine excretion. Neither urinary cystine nor cysteine excretion was affected by dietary sodium intake. A lacto-ovo-vegetarian diet is particularly suitable for the dietary treatment of cystinuria, since the additional alkali load may reduce the amount of required alkalizing agents.


1996 ◽  
Vol 30 (4) ◽  
pp. 337-346 ◽  
Author(s):  
S. W. Y. Chan ◽  
P. C. Reade

Wistar Shionogi rats of the ( od/od) substrain with the osteogenic disorder are unable to synthesize L-ascorbic acid ( L-AA) and appear to be an appropriate animal model for studying the effect of L-AA in carcinogenesis. To determine the minimal L-AA requirements of these animals for prolonged survival in a satisfactory physical condition during experimentation, four concentrations of L-AA (0.33 g/l, 0.67 g/l, 1.67 g/l and 3.33 g/l) were administered via drinking water to four groups of animals ( n=2). Their water intake per cage was recorded three times weekly and the plasma L-AA levels were determined at the start, after 2, 4, 8 and 12 weeks and at the termination of the experiment. To simulate the procedures to be undertaken in oral mucosal carcinogenesis experiments, the animals were gently restrained and a designated amount of sterile NaCl was applied to the palatal mucosa three times a week for 26 weeks. The L-AA supplement group with the lowest concentration (0.33 g/l L-AA) achieved mean plasma levels of 7 ± 1.38 μM, approximately one-eighth that of the normal level (mean plasma L-AA level in outbred Wistar rats was found to be 58 ± 3 μM) whilst those in the higher supplement group (3.33 g/l L-AA) achieved a mean of 18 ± 1.25 μM. All of the animals employed in the present study survived for 26 weeks and showed no clinical signs of L-AA deficiency during this period.


2017 ◽  
Vol 61 (4) ◽  
pp. 43-48
Author(s):  
Augustyn Dolatkowski ◽  
Tadeusz Doboszyński ◽  
Bogdan Łokucijewski

Abstract Numerous research works indicate that staying in a hyperbaric environment is a stressor. We have undertaken studies using an animal model to determine the effect of hyperbaria on adrenocortical secretion and the level of adrenal ascorbic acid (a.a.a.). The research was conducted on 70 male hooded rats, which were divided into groups and subjected to hyperbaric air and oxygen at an overpressure of 1 and 3 atn, with some of the animals being additionally burdened with physical effort (swimming). It was found that short-term exposures (30 minutes) of rats to hyperbaric conditions caused a decrease in the content of a.a.a. With a prolonged (3-hour) exposure to 3 atm air the a.a.a. content returns to a normal level. A reduction in the a.a.a. content indicates the presence of stress in hyperbaric conditions in the rat, however, it does not allow to determine its intensity with the method used in the study.


1995 ◽  
Vol 23 (2) ◽  
pp. 111-117 ◽  
Author(s):  
�. Lindell ◽  
T. Denneberg ◽  
E. Hellgren ◽  
J. -O. Jeppsson ◽  
H. -G. Tiselius

Author(s):  
Paul Otto Schwille ◽  
Mahimaidos Manoharan ◽  
Angelika Schmiedl

AbstractBackground: The site of origin of idiopathic recurrent calcium urolithiasis (IRCU) – a disorder characterized by stones composed of calcium oxalate (CaOx) and/or calcium phosphate (CaPi) – is uncertain, because in urine such risk factors for stones as disturbed Ox, Ca and Pi are not regularly observed. Aims: To evaluate whether imbalance of antioxidants and oxidants might be present in IRCU patients that is then followed by abnormal urine, plasma and intracellular mineral homeostasis, and stones. Methods: Males were investigated in the laboratory under standardized conditions, and three trials were organized. Trial 1 was cross-sectional, comparing IRCU patients with (n=111) and without stones in situ (n=126), focussing on abnormalities of oxypurines and minerals in urine and plasma, and metabolic activity (MA) of the disease. Trial 2 was partly controlled (n=14 healthy subjects; n=53 IRCU patients), comparing the plasma levels of total antioxidant status (TAS) and uric acid, the major antioxidant in humans, using the subsets Low (n=26) and High (n=27) TAS among IRCU patients in terms of plasma levels of uric acid, ascorbic acid, albumin, α-tocopherol and minerals, urinary minerals, CaOx and CaPi (hydroxyapatite) supersaturation. Trial 3, comprising stone-free IRCU patients (n=8) and healthy controls (n=8), compared minerals and mineral ratios in plasma and red blood cells (RBCs). Established analytical methodologies were used throughout. Results: In trial 1, uricemia, hypoxanthinuria and proteinuria were elevated, fractional urinary clearance (FE) of uric acid was decreased in stone-bearing patients, and MA correlated positively with uricemia and urinary total protein excretion. In trial 2, TAS was significantly decreased in IRCU patients vs. healthy controls; low TAS coincided with low plasma uric acid and albumin, unchanged ascorbic acid, α-tocopherol and parathyroid hormone, but increased FE-uric acid and Pi excretion; the latter correlated negatively with TAS. In trial 3, plasma minerals were significantly decreased in IRCU patients vs. controls, and Ca/Pi, (Ca/Pi)/Mg and (Ca/Pi)/Na molar ratios increased; the latter ratio was also increased in RBCs, and correlated highly positively with the same ratio in plasma. Conclusions: In IRCU 1) renal stones in situ in combination with high fasting uricemia, high hypoxanthinuria and protein-uria, and high MA suggest that a systemic metabolic anomaly underlies stone formation; 2) antioxidant deficit is frequent, unrelated to the presence or absence of stones but apparently related to poor renal uric acid recycling, low uricemia and albuminemia, exaggerated urinary Pi excretion, and low MA; 3) the combination of low plasma TAS, disordered Ca/Pi and other mineral ratios in urine, plasma and RBCs, but unchanged urinary Ca salt supersaturation is compatible with the view that CaPi solid and Ca microlith formation start inside oxidatively damaged cells.


Author(s):  
Angelo D. Supp ◽  
Silvio Avila ◽  
Gustavo A. Mastella ◽  
Louyse Damásio ◽  
Isabela H. de Oliveira ◽  
...  

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