Marked reductions in bioactive insulin-like growth factor I (IGF-I) during hemodialysis

Serum levels of bioactive IGF1 and physiological markers of ageing in healthy adults

“…Serum IGFBP1 levels have previously been demonstrated to associate inversely with bioactive IGF1 (31). During haemodialysis a fivefold increase in IGFBP1 was accompanied by a 50% decrease in bioactive IGF1 despite a marginal reduction in total IGF1 (32). Our data support this finding because we found that IGFBP1 significantly and negatively predicted bioactive IGF1 in multiple linear regression analysis.…”

Lack of circulating bioactive and immunoreactive IGF-I changes despite improved fitness in chronic kidney disease patients following 48weeks of physical training

“…As IGF-I is known to have anabolic and mitogenic effects [9], reduced bioavailability of IGF-I may be related to impaired muscle protein synthesis and muscle wasting in this population [10]. Interestingly, immunoreactive IGF-I levels have been reported to be in the normal range, while free and bioavailable IGF-I have been reported to be reduced in these individuals [2,3,8,11,12]. Diminished levels of free and bioactive IGF-I in patients with CKD have been attributed to increased circulating levels of IGFBPs due to reduced clearance with impaired kidney function [2,8].…”

Insulin–glucose infusion given before hemodialysis increases IGF-I in type 2 diabetes patients with chronic kidney disease

“…This result is in contrast to the result after a dialysis session not preceded by an insulin infusion, where total IGF-I is unchanged or slightly decreased and IGFBP-1 increases suggesting a decrease of bioavailable IGF-I [16,25]. Free IGF-I and bioavailable IGF-1 have been shown to decrease by 35-50% during hemodialysis [25]. Our present findings are most likely due to an insulin effect both on IGF-I secretion and on IGFBP-1 production as has been shown in type 1 diabetes patients [11] and in healthy subjects [26].…”

“…This result is in contrast to the result after a dialysis session not preceded by an insulin infusion, where total IGF-I is unchanged or slightly decreased and IGFBP-1 increases suggesting a decrease of bioavailable IGF-I [16,25]. Free IGF-I and bioavailable IGF-1 have been shown to decrease by 35-50% during hemodialysis [25].…”