Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0730345 (microalbuminuria)
 4,018 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nephropathy is a serious microvascular complication of diabetes mellitus which is preceded by a period of microalbuminura. Increased loss of proteoglycan (PG) from glomerular basement (GBM) has been postulated to alter glomerular charge selectivity which contributes to urinary loss of albumin. In this study we measured the excretion of urinary glycosaminoglycans (GAG), the degradation products of PG, in 82 non-insulin-dependent (NIDDM) (Type 2) diabetic and 34 non-diabetic subjects. We found that diabetic subjects had a significantly higher GAG urinary excretion rate compared to non-diabetic subjects (12.54 +/- 5.67 vs 8.80 +/- 3.99 micrograms glucuronic acid min-1, p = 0.0001). Categorizing for albuminuric status shows that the diabetic normo-, micro- and macroalbuminuric groups have a higher GAG excretion rate than non-diabetic subjects. Heparan sulphate (HS) GAG urinary excretion was measured in 25 samples from diabetic subjects and 18 non-diabetic subjects. Diabetic subjects excreted more HS GAG than controls both as a rate or as a percentage of total GAG (3.70 +/- 1.94 vs 2.38 +/- 1.48 micrograms glucosamine min-1, p = 0.02; 31.6% +/- 12.5 vs 23.1% +/- 10.4, p = 0.02). Categorizing for albuminuric status shows that micro- and macro-albuminuric groups have a significantly higher HS GAG excretion rate than non-diabetic subjects. We conclude that, as in IDDM, excretion of GAG and HS GAG is higher in NIDDM and may precede the development of microalbuminuria.
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PMID:Urinary glycosaminoglycan excretion in NIDDM subjects: its relationship to albuminura. 886 53

Rats were implanted with mini osmotic pumps delivering sodium [35S]sulphate and their newly synthesized proteoglycans were labelled over a 146 h period (steady-state labelling). Proteoglycan turnover was measured in vivo using a chase protocol. Glomerular proteoglycans were recovered quantitatively and the perlecan present was isolated by immunoprecipitation. The procedure allows newly synthesized proteoglycans to be quantified in mass units (pmol of glycossminoglycan sulphate) after labelling and during the chase. Ultrastructural-immunogold experiments identified the location of perlecan as the glomerular basement membrane and mesangial matrix. Perlecan in the basement membrane was quantified using the ultrastructural-immunogold technique. Perlecan comprises about 10% of the total glomerular proteoglycans, which are otherwise associated with glomerular cells and the mesangium. Both the total glomerular heparan sulphate proteoglycans and perlecan turn over rapidly (t1/2 approximately 3-4 h and < 3 h respectively). In contrast, turnover of proteoglycans in other tissues was slow, except in the liver where the heparan sulphate and chondroitin sulphate t1/2 values were 16 h and 9 h respectively. Microalbuminuria was induced with a low-dose regimen of puromycin aminonucleoside. At the onset of microalbuminuria (5 days) there was no change in the level of newly synthesized perlecan, or in perlecan in the glomerular basement membrane detected by immunogold labelling. Newly synthesized perlecan had undergone a minimal change in turnover rate by day 5 in puromycin aminonucleoside-treated rats. In contrast, the total glomerular proteoglycan population showed a dramatic decrease in turnover by day 5. Since there was no evidence of accumulation of glomerular proteoglycans on either day 5 or day 6, it is likely that decreased turnover of cell-associated proteoglycans is accompanied by an equivalent decrease in their synthesis.
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PMID:A steady-state labelling approach to the measurement of proteoglycan turnover in vivo and its application to glomerular proteoglycans. 894 1