Aging related alterations of serum insulin-like growth factor-1 (somatomedin-c)‎ and its binding protein-3 concentrations in type-2 diabetic patients with hypertension

Abstract EN

Background : It is claimed that many, but not all, circulating hormones decline with age.

With this regard, serum somatomedin-C or what is called insulin like growth factor-1 (IGF-I) level is reduced by about 33% in elders.

Also serum IGFBP-3 level is reduced among elders, but not to the same extent as IGF-I.

At the same time, type-II diabetes mellitus (non-insulin dependent diabetes mellitus : NIDDM) occurs in approximately about 18% of persons over 65 years of age.

In this respect, IGF-1 hypo function has been implicated in the path physiology of diabetes mellitus in elderly.

Aim : The present study has been designed to measure the circulating serum IGF-1 and IGFBP-3 concentrations in elderly diabetic (type II) patients with hypertension in hope to clarify the state of these two substances in them.

Subjects : This study investigated 25 elderly type 2 diabetic patients with age range from 60 to 76 years.

In addition, 40 middle age diabetics with age range from 40 to 55 years were studied.

At the same time 15 normoglycemic-normotensive subjects of matched age, sex and body weight representing the control group were investigated.

Methods : Serum IGF-1 and IGFBP-3.

concentrations were determined according to IFCC recommendations in the three groups of subjects.

Results : The circulating IGF-1 and IGFBP-3 mean values were significantly decreased in elderly (age ? 60 years) and middle aged (age 40-55 years) sole diabetic, diabetic- hypertensive and diabetic hypertensive with ischemic heart disease (IHD) groups in comparison to non diabetic matched control group.

Moreover, the corresponding data in middle age groups were significantly higher than those of elderly groups.

Conclusion : Serum IGF-1 (somatomedin-C) and IGFBP-3 concentrations showed progressive decline in their levels with aging.

Moreover, IGF-1 and IGFBP-3 concentrations were most markedly decreased in diabetic patients with hypertension singly or combined with coronary artery disease.

So, shortage of IGF-1 could be a key factor in the aging process and in the development of type 2 diabetes mellitus in such subjects.