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Many studies on cirrhotic patients have shown that insulin-like growth factor 1 (IGF-1) plasma levels are related to the severity of liver dysfunction. This result suggests that IGF-1 is probably useful for monitoring liver function in the perioperative course of orthotopic liver transplantation (OLT). Growth hormone (GH), IGF-1 plasma levels, and routine liver function tests were measured in 15 adult cirrhotic patients undergoing OLT. Measurements were made at the beginning of the operation; during OLT; 24 hours after reperfusion; and in the morning on days 7, 30, and 90. Twenty age-matched healthy volunteers with normal liver function served as controls. The study group had significantly higher GH levels and lower IGF-1 levels in the preoperative period compared with the controls. All patients achieved a complete functional hepatic recovery 1 month after OLT, although in 6 of them, the graft had an initial poor function (Group-IPF). GH and IGF-1 levels achieved near normal range within 1 week after OLT, and they had no significant correlations with other routine biochemistry tests in this period. IGF-1 levels in Group-IPF rose more slowly than in the group with a normal recovery of graft function. Surprisingly, 24 hours after reperfusion, IGF-1 levels were higher in Group-IPF than in the group with normal graft function. In conclusion, the severe GH/IGF-1 axis impairment found in patients with end-stage cirrhosis reverted very rapidly in the first T he liver is a central organ in the growth hormone (GH) /insulin-like growth factor-1 (IGF-1) axis. 1 IGF-1 is produced almost entirely by the liver and is the main promoter of anabolic GH effects on protein, carbohydrate, and lipid metabolism. 2,3 Moreover, IGF-1 synthesis is controlled by GH and has a negative feedback control on pituitary GH secretion. 4 Liver cirrhosis is characterized by high serum levels of GH, a reduction in the number of liver GH receptors, and a parallel decrease in serum IGF-1. 5 This particular endocrine disorder can be explained by several mechanisms, such as decreased liver cell mass, malnutrition, portal hypertension, and hyperestrogenism. [5][6][7] The influence of these various factors, most of which are related to the severity of the liver disease, could account for the high prognostic significance of IGF-1 as a predictor of survival in cirrhotic patients and as a potential early indicator of liver dysfunction. 7,8 Several authors 9 -15 have shown that successful orthotopic liver transplantation (OLT) brings about a complete recovery of the GH/IGF-1 axis in patients with end-stage liver disease. However, these studies have not considered the timing of such an GH/IGF-1 axis recovery, particularly in the early stages after OLT. The assays in these reports, which focused mainly on pediatric patients, were carried out from months up to years after liver transplantation. The functional quality of the graft in the early hours after OLT is a major determinant of the future clinical course of transplanted patients, however, and standard liv...

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To examine physical exercise-related changes in urinary excretion of protein/peptide hormones and to correlate modifications with the general increase in post-exercise proteinuria, urine C-peptide, insulin and insulin-like growth factor-I (IGF-I) and their plasma concentrations were measured. Plasma and urinary C-peptide, insulin and IGF-I before (Bex) and at the end (Eex) of physical exercise (a 2.5-hour competition, 102 km) were analysed in 20 young cyclists. At Eex compared with Bex, concentration of urinary C-peptide decreased slightly but significantly (21.3 +/- 2.7 vs. 13.5 +/- 1.7 nmol/l), but urinary insulin and urinary IGF-I concentrations significantly increased at Eex (92.5 +/- 4.2 vs. 131.4 +/- 15.7 pmol/l and 10.0 +/- 2.1 vs. 33.6 +/- 3.8 pmol/l, respectively). Plasma insulin and plasma C-peptide significantly decreased, whereas plasma IGF-I was unchanged. Urinary concentrations of total proteins and creatinine significantly increased. Both Eex urinary C-peptide/urinary protein and urinary C-peptide/urinary creatinine ratios were significantly reduced. The correlation between C-peptide and insulin in plasma was confirmed at Bex as well as Eex, but in urine only at Bex. An increased renal tubular reabsorption of C-peptide at the end of exercise might be suggested, but the expected values considering creatinine excretion were almost three times less. The Eex urinary insulin concentration was higher than expected, considering the circulation levels, but lower when compared with the expected concentration considering creatinine excretion. Physical exercise proteinuria, related to an increased protein filtration and a saturation of the mechanisms responsible for the reabsorption, does not appear similar for all peptide hormones.