Abstract
Human crude and recombinant interleukin 1 (IL-1) was found to dose- and time-dependently affect the biosynthesis of (pro)insulin in isolated rat islets of Langerhans. Incubation of rat islets with either 0.5 U/ml or 5 U/ml of crude IL-1 for 1 h had no detectable effect on (pro)insulin biosynthesis. After 24 hours of exposure 0.5 U/ml of crude or 0.6 ng/ml of recombinant IL-1 (beta) increased the (pro)insulin biosynthesis by 42% and 58%, respectively, whereas a 10-fold greater concentration of IL-1 decreased the (pro)insulin biosynthesis by 74% and 89%, respectively. The increase in (pro)insulin biosynthesis was accompanied by an increase in total protein biosynthesis indicating a nonspecific stimulatory action of low IL-1 concentrations. In contrast, high IL-1 concentrations caused a more selective decrease of the (pro) insulin biosynthesis when compared to the total protein biosynthesis. In addition, low IL-1 concentrations were found to increase and high concentrations to decrease the relative levels of pre-proinsulin mRNA suggesting that IL-1 may act both at a pre- and post-translational level of insulin biosynthesis.
Original language | English |
---|---|
Journal | Diabetologia |
Volume | 30 |
Issue number | 7 |
Pages (from-to) | 474-80 |
Number of pages | 7 |
ISSN | 0012-186X |
Publication status | Published - Jul 1987 |
Keywords
- Animals
- Chromatography, High Pressure Liquid
- Insulin
- Interleukin-1
- Islets of Langerhans
- Proinsulin
- Protein Biosynthesis
- Protein Precursors
- RNA, Messenger
- Rats
- Rats, Inbred Strains