Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0033687 (proteinuria)
 24,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have measured plasma von Willebrand factor (VWF) as the factor VIII-related antigen, plasma fibronectin, and two of the serum somatomedins, insulin-like growth factor I (IGF I) and IGF II, in 51 diabetic patients and 25 nondiabetic control subjects. VWF was significantly higher in the diabetic group than in the controls (173 +/- 9% SEM versus 101 +/- 9%, P less than 0.001), as has been reported by others. However, within the diabetic group there was no significant difference in VWF between those patients without retinopathy, those with background or proliferative retinopathy, or those with macular edema. There was also no difference in VWF between the diabetic subjects with and those without proteinuria. These results rule against a previously advanced hypothesis that the increase in VWF in patients with diabetes is secondary to microangiopathy. No significant difference was observed in fibronectin, IGF I, or IGF II between the diabetic and control groups, between the diabetic group without retinopathy and the retinopathic subgroups, and between the diabetic subjects with and without proteinuria. In the diabetic patients, there was no correlation between diabetic control as assessed by glycosylated hemoglobin and glycosylated serum protein, and the plasma levels of VWF, fibronectin, IGF I, or IGF II. The results of this study strongly suggest that neither plasma VWF, fibronectin, IGF I, nor IGF II plays an important primary role in the pathogenesis of diabetic microvascular disease, although one or more of these factors might play a permissive role.
 ...
PMID:Von Willebrand factor (VIII R:Ag), fibronectin, and insulin-like growth factors I and II in diabetic retinopathy and nephropathy. 636 66

To determine whether insulin-like growth factor I (IGF-I) affects kidney function in patients with end-stage chronic renal failure, we administered recombinant human IGF-I (rhIGF-I) (100 micrograms/kg body wt subcutaneously twice daily) to nine individuals with baseline inulin clearances below 21 ml/min/1.73 m2. Four patients were treated for four days (short-term treatment) and five for periods between 13 and 27 days (long-term treatment). Administration of rhIGF-I increased inulin clearance, p-aminohippurate (PAH) clearance and the percent tubular reabsorption of filtered phosphate, and decreased plasma creatinine, blood urea nitrogen (BUN) and plasma phosphate during short-term administration. Kidney volume was unchanged in patients receiving the growth factor. rhIGF-I did not cause weight gain, proteinuria or hypoglycemia. Inulin clearance was not increased significantly above baseline after 13 or 20 days of IGF-I administration. PAH clearance remained elevated after 13 days, but not after 20 days of IGF-I. Levels of total circulating IGF-I were elevated above basal levels during the entire course of long-term IGF-I administration. In contrast, levels of circulating IGF binding protein 3 (IGFBP3) declined over time. Side effects related to IGF-I forced discontinuation of its use in two of five patients undergoing long-term treatment, and side-effects possibly related to IGF-I prompted discontinuation of its use in two others. We conclude that rhIGF-I can enhance glomerular filtration rate and renal plasma flow when administered short-term to humans with end-stage chronic renal renal failure. Further studies will be required to define its efficacy and usefulness long-term.
 ...
PMID:Effects of IGF-I on renal function in end-stage chronic renal failure. 793 38

Clinical and experimental data have indicated that heavy proteinuria in renal glomerular diseases is associated with the formation of tubulo-interstitial fibrosis and contributes to the progression of renal failure. Albumin in glomerular ultrafiltrate does not appear to cause this sequelae, rather than compounds that are associated with ultrafiltered plasma proteins. One such protein-bound factor could be insulin-like growth factor I (IGF-I). The present studies show that in nephrotic rats, IGF-I is ultrafiltered in conjunction with IGF-binding protein-2 and is present in proximal tubular fluid at 1.35 nM. Proximal tubular fluid from nephrotic rats autophosphorylates IGF-I receptors in cultured proximal tubular cells. Nephrotic, but not control, rat proximal tubular fluid increases the [3H]thymidine incorporation in cultured tubular cells, and neutralizing IGF-I-receptor antibodies partially inhibit this activity. Incubation of cultured proximal tubular cells with an extract that was prepared from nephrotic rat urine increases the secretion of collagen types I and IV. Secretion of the two collagens is in part ameliorated by neutralizing IGF-I-receptor antibody. In concert, these findings suggest that the IGF-I present in nephrotic rat tubular fluid is bioactive and may contribute to the development of tubulo-interstitial fibrosis in chronic nephrotic glomerular diseases.
 ...
PMID:Bioactivity of glomerular ultrafiltrate during heavy proteinuria may contribute to renal tubulo-interstitial lesions: evidence for a role for insulin-like growth factor I. 869 Jul 82

Experimental studies in rats have demonstrated an association between focal segmental glomerulosclerosis (FSGS) and growth hormone, but patients with FSGS complicating acromegaly are very rare. In this report we present a case of FSGS associated with acromegaly. With a long history of soft tissue swelling of hands and feet, elevated plasma growth hormone levels and other biochemical abnormalities, a 53-year old male had suffered from acromegaly for over 15 years. He had moderate proteinuria for 6 years, but never evidenced nephrotic syndrome. A renal biopsy specimen revealed FSGS and glomerular hypertrophy. Trans-sphenoidal surgical removal of the pituitary adenoma resulted in the normalization of elevated growth hormone and insulin-like growth factor I levels, but proteinuria continued. This case suggests that the overproduction of growth hormone may participate, at least in part, in the development of human FSGS. It is possible that once FSGS is present in an acromegalic patient, cessation of GH overproduction may not be enough to reverse it.
 ...
PMID:Focal segmental glomerulosclerosis associated with acromegaly. 1149 62

Microalbuminuria is the earliest detectable clinical abnormality in diabetic glomerulopathy. On a molecular level, metabolic pathways activated by hyperglycemia, glycated proteins, hemodynamic factors, and oxidative stress are key players in the genesis of diabetic kidney disease. A variety of growth factors and cytokines are then induced through complex signal transduction pathways. Transforming growth factor-beta 1 (TGF-beta1) has emerged as an important downstream mediator for the development of renal hypertrophy and the accumulation of mesangial extracellular matrix components, but there is limited evidence to support its role in the development of albuminuria. The loss of proteoglycans in the glomerular basement membrane (GBM) has been recently questioned as causative of the albuminuria, and current research has focused on the podocyte as a central target for the effects of the metabolic milieu in the development and progression of diabetic albuminuria. Podocyte-derived vascular endothelial growth factor (VEGF), a permeability and angiogenic factor whose expression is increased in diabetic kidney disease, is perhaps a major mediator of the increased protein filtration. Decreased podocyte number and/or density as a result of apoptosis or detachment, GBM thickening with altered matrix composition, and a reduction in nephrin protein in the slit diaphragm with podocyte foot process effacement, all comprise the principal features of diabetic podocytopathy that clinically manifests as albuminuria and proteinuria. Many of these events are mediated by angiotensin II whose local concentration is stimulated by high glucose, mechanical stretch, and proteinuria itself. Angiotensin II in turn stimulates podocyte-derived VEGF, suppresses nephrin expression, and induces TGF-beta1 leading to podocyte apoptosis and fostering the development of glomerulosclerosis. Proteinuria can then induce in tubular cells a genetic program leading to tubulointerstitial inflammation, fibrosis and tubular atrophy. Besides direct effects of albuminuria on tubular cells, pathophysiological changes in the ultrafiltration barrier lead to an increased tubular filtration of various growth factors (TGF-beta1, insulin-like growth factor I) that may further alter the function of tubular cells. Moreover, angiotensin II also stimulates uptake of ultrafiltered proteins into tubular cells and enhances the production of proinflammatory and profibrotic cytokines within the cells. Migration of macrophages and other inflammatory cells into the tubulointerstitium occurs. Increased synthesis and decreased turnover of extracellular matrix proteins in tubular cells and interstitial fibroblasts contribute to interstitial fibrosis. In addition, under locally high concentrations of angiotensin II and TGF-beta1, tubular cells may change their phenotype and become fibroblasts by a process called epithelial to mesenchymal transition (EMT) which contributes to interstitial fibrosis and tubular atrophy because of vanishing epithelia cells. An alternative explanation for the development of albuminuria in diabetic nephropathy that involves primarily an abnormality in tubular handling of ultrafiltered proteins has also been suggested, but these changes are not necessarily exclusive of the altered properties of glomerular ultrafiltration barrier.
 ...
PMID:Pathogenesis of the podocytopathy and proteinuria in diabetic glomerulopathy. 1822 Jun 94