Diabetes studies, controlled insulin system

Morishita, M., et al. 2006. Novel oral insulin delivery systems based on complexation polymer hydrogels Single and multiple administration studies in type 1 and 2 diabetic rats. J Control Release 110 587. 

Studies on glucose-induced polymer swelling have focussed on developing membranes that could serve in systems for controlled delivery of insulin to diabetics (3,4). It has been shown that hydrophobic methacrylate copolymers undergo a sharp swelling transition as the pH is decreased from 7 to 6 (3-7). However, the kinetics of the transition are too slow for the proposed application to glucose delivery. 

Mogensen CE, Neidam S, Tikkanen I, Oren S, Viskoper R, Watts RW, et al. Randomised controlled trial of dual blockade of renin-angiotensin system in patients with hypertension, microalbuminuria, and non-insulin dependent diabetes the candesartan and lisinopril microalbuminuria (CALM) study. BMJ 2000 321 1440-4,... 

Possible advantages of intraperitoneal versus subcutaneous insulin include the avoidance of erratic absorption (both rate and extent of absorption), convenience, avoidance of subcutaneous injection site-related complications, and prevention of peripheral hyperinsulinemia. Insulin appears to be cleared into the systemic compartment by an active transport process, or via the peritoneal lymphatics. A number of studies have demonstrated the bioavailability of intraperitoneal insufin to be about 25% to 30%, although none clearly compares the clinical effectiveness of intraperitoneal versus subcutaneous insufin in diabetes control. Insufin requirements for PD patients may be greater than in hemodialysis patients because of the continued absorption of dextrose from the peritoneal cavity. Furthermore, because of adsorption of insufin to the polyvinyl chloride bag and administration set, the intraperitoneal dose of insufin often needs to be two to three times the subcutaneous maintenance dose. 

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