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Relationship between plasma uridine and urinary urea excretion.
Tuneyoshi Ka1, Taku Inokuchi, Daisuke Tamada
1Division of Endocrinology and Metabolism, Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Hyogo 663-6801, Japan.
Metabolism: Clinical and Experimental
|October 23, 2009
Summary
Plasma uridine concentration correlates with urinary urea excretion in healthy males. This suggests increased pyrimidine synthesis impacts nitrogen metabolism and plasma uridine levels.
Area of Science:
- Biochemistry
- Human Physiology
- Metabolic Research
Background:
- Uridine, a pyrimidine nucleoside, plays a role in cellular metabolism.
- Understanding plasma uridine's relationship with nitrogen excretion is crucial for metabolic health.
- Previous research has not fully elucidated the link between plasma uridine and urea excretion.
Purpose of the Study:
- To investigate the relationship between plasma uridine concentration and urinary urea excretion in healthy males.
- To explore correlations between plasma uridine and other urinary metabolites and physiological parameters.
- To determine the primary drivers of plasma uridine levels in a healthy cohort.
Main Methods:
- Study included 45 healthy males with normouricemia and normal blood pressure.
- Collected 24-hour urine and plasma samples after an overnight fast.
- Dietary intake was analyzed, and simple and multiple regression analyses were performed.
Main Results:
- Simple regression revealed correlations between plasma uridine and urinary urea, uric acid, uridine, uric acid clearance, and purine intake.
- Multiple regression analysis identified a significant positive relationship exclusively between plasma uridine and urinary urea excretion.
- These findings indicate a specific link between plasma uridine and urea metabolism.
Conclusions:
- Plasma uridine concentration is positively associated with urinary urea excretion in healthy individuals.
- Increased de novo pyrimidine synthesis may lead to elevated plasma uridine via nitrogen catabolism.
- The study highlights a potential metabolic pathway connecting pyrimidine synthesis to nitrogen excretion.
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