We have studied the chemical basis of drug binding defects in uremia and have chemically identified the binding inhibitor to be 2-hydroxybenzoylglycine. This inhibitor, when added to normal human serum in vitro, induces the binding defects similar to those observed in uremic serum in vitro. This proposal describes our plans to further investigate the role of 2-hydroxybenzoylglycine in the pathophysiology of the uremic state. The first phase of our work will concentrate on the mechanism by which 2-hydroxybenzoylglycine inhibits the binding of acidic drugs and its effects on the activity of pharmacological agents. When these studies are completed, the studies will be extended to elucidate the role of 2-hydroxybenzoylglycine as one of the so-called """"""""uremic toxins"""""""". Since none of the previous putative """"""""uremic toxins"""""""" has been shown to explain any specific abnormalities in uremia, it seems important to evaluate other potential effects of 2-hydroxybenzoylglycine. Initial studies will be undertaken in experimental animals (rats) to determine the tissue distribution and tissue binding sites of 2-hydroxybenzoylglycine. Subsequent studies will be developed to elucidate its possible role in producing """"""""uremic"""""""" encephalopathy, neuropathy, seizure disorders, hemolytic anemia, lipid disorders, and other problems associated with chronic renal failure. Exogenous sources of 2-hydroxybenzoylglycine and its precursors are multiple. We plan to study the precise biochemical mechanisms involved in the genesis of 2-hydroxybenzoylglycine, possible methods of removal of the substance from uremic serum which could become clinically adaptable, and limit the biogenesis of the compound in uremic patients by control of dietary intake of foods containing 2-hydroxybenzoylglycine precursors. Further information gained from the study of 2-hydroxybenzoylglycine as a pathological agent will definitely aid in the correction of binding defects in uremic patients and other abnormalities which may be due to the accumulation of 2-hydroxybenzoylglycine.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis, Diabetes, Digestive and Kidney Diseases (NIADDK)
Type
Research Project (R01)
Project #
5R01AM026807-05
Application #
3151668
Study Section
General Medicine B Study Section (GMB)
Project Start
1980-12-01
Project End
1987-03-31
Budget Start
1985-04-01
Budget End
1986-03-31
Support Year
5
Fiscal Year
1985
Total Cost
Indirect Cost
Name
Temple University
Department
Type
Schools of Medicine
DUNS #
City
Philadelphia
State
PA
Country
United States
Zip Code
19122
Wadsworth, S J; Suh, B (1988) In vitro displacement of bilirubin by antibiotics and 2-hydroxybenzoylglycine in newborns. Antimicrob Agents Chemother 32:1571-5
Suh, B; Wadsworth, S J; Lichtenwalner, D M (1987) Demonstration of 2-hydroxybenzoylglycine as a drug binding inhibitor in newborn infants. J Clin Invest 80:1125-31
Suh, B; Lee, H W; Hong, S Y et al. (1986) A new HPLC analytical method for o-hydroxyhippuric acid in uremic serum. J Biochem Biophys Methods 13:211-20