Soluble, fatty acid acylated insulins bind to albumin and show protracted action in pigs.
We have synthesized insulins acylated by fatty acids in the epsilon-amino group of LysB29. Soluble preparations can be made in the usual concentration of 600 nmol/ml (100 IU/ml) at neutral pH. The time for 50% disappearance after subcutaneous injection of the corresponding TyrA14(125I)-labelled insulins in pigs correlated with the affinity for binding to albumin (r = 0.97), suggesting that the mechanism of prolonged disappearance is binding to albumin in subcutis. Most protracted was LysB29-tetradecanoyl des-(B30) insulin. The time for 50% disappearance was 14.3 +/- 2.2 h, significantly longer than that of Neutral Protamine Hagedorn (NPH) insulin, 10.5 +/- 4.3 h (p < 0.001), and with less inter-pig variation (p < 0.001). Intravenous bolus injections of LysB29-tetradecanoyl des-(B30) human insulin showed a protracted blood glucose lowering effect compared to that of human insulin. The relative affinity of LysB29-tetradecanoyl des-(B30) insulin to the insulin receptor is 46%. In a 24-h glucose clamp study in pigs the total glucose consumptions for LysB29-tetradecanoyl des-(B30) insulin and NPH were not significantly different (p = 0.88), whereas the times when 50% of the total glucose had been infused were significantly different, 7.9 +/- 1.0 h and 6.2 +/- 1.3 h, respectively (p < 0.04). The glucose disposal curve caused by LysB29-tetradecanoyl des-(B30) insulin was more steady than that caused by NPH, without the pronounced peak at 3 h. Unlike the crystalline insulins, the soluble LysB29-tetradecanoyl des-(B30) insulin does not elicit invasion of macrophages at the site of injection. Thus, LysB29-tetradecanoyl des-(B30) insulin might be suitable for providing basal insulin in the treatment of diabetes mellitus.
Markussen
J
J
Novo Research Institute, Bagsvaerd, Denmark.
Havelund
S
S
Kurtzhals
P
P
Andersen
A S
AS
Halstrøm
J
J
Hasselager
E
E
Larsen
U D
UD
Ribel
U
U
Schäffer
L
L
Vad
K
K
Jonassen
I
I
D000215:Acylation; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D007328:Insulin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D007457:Iodine Radioisotopes; D007700:Kinetics; D008239:Lysine; D008264:Macrophages / Q000187:drug effects / Q000473:pathology / Q000502:physiology; D008657:Metabolic Clearance Rate; D011485:Protein Binding; D011972:Receptor, Insulin / Q000378:metabolism*; D012709:Serum Albumin / Q000378:metabolism*; D012867:Skin / Q000187:drug effects; D013552:Swine
D001786:Blood Glucose; D007328:Insulin; D007457:Iodine Radioisotopes; D012709:Serum Albumin; D011972:Receptor, Insulin; D008239:Lysine