The importance of insulin like growth factor-1 (IGF-1) in coronary artery disease (CAD) due to wide range of its biological effects and its therapeutic potential has already been described. Our aim was to evaluate possible influence of IGF-1 serum level changes on coronary atherosclerosis. In case of existence of such association our further aim was to verify and explain this phenomenon by examination of promoter P1 of IGF-1 gene and receptor gene for IGF-1. The study was performed in 101 consecutive patients undergo for routine coronary angiography.
Quantitative and qualitative assessment of coronary atherosclerosis was performed respectively by estimation of the number of culprit lesions in coronary arteries and by Gensini scores calculation. IGF-1, IGFBP3 and plasma lipoproteins were measured in all patients. In addition, we evaluated DNA from 101 patients, isolated from blood cells, which was amplified by using PCR with sophisticated primers for P1 promoter of elevate IGF-1 gene and IGF-1 receptor gene, then analysed utilizing SSCP technique and automatically sequenced. We observed significantly increased serum IGF-1 levels in patients with “3 vessel disease” and with high score in Gesini scale when compared to those without any narrowing lesions in coronary arteries and 0 Gensini scores.
There are no significant associations between the observed single nucleotide polymorphism (SNP) and coronary atherosclerosis or with levels of circulating IGF-1. We found no structural polymorphism in receptor gene for IGF-1 or in its extracellular domain (axon 16 to 21). The effect of increased IGF-1 serum level in our study was probably independent from structural polymorphism in receptor gene for IGF-1. It is also called as Presence of irregularity in region between 1115 and 784 not in P1 promoter of insulin like growth factor-1 gene may indicate beneficial effects on coronary arteries in a group of patients with stable angina.
The Levels of IGF-1
Serum insulin like growth factor-1 (IGF-1) is a sensitive marker of growth hormone (GH) activity. The levels of IGF-1 vary widely, peaking during puberty and declining with advancing age. During adolescence serum IGF-1 levels tend to correlate better with pubertal stage rather than chronological age. Here we discuss two cases of delayed puberty both in their 20s who presented with high serum IGF-1 but no clinical or bio-chemical evidence of it’s as confirmed by appropriate GH response to an oral glucose challenge. Both individuals achieved full pubertal status with testosterone replacement therapy and their serum IGF-1 levels settled into normal age specific range.
We suggest that in the chronologically adult individuals with delayed puberty serum IGF-1 should not be any interpreted on the basis of age specific normal values but rather on their pubertal status. Furthermore, in the absence of another cause of elevate IGF-1 the expectation is that IGF-1 levels willdecline towards age normative ranges following androgen replacement therapy. The measurement of serum insulin like growth factor 1 (IGF-1) is a useful screening test for acromegaly. The normal reference range for it varies widely picking during puberty.