Comparative effects of Citrullus colocynthis, sunflower and olive oil-enriched diet in streptozotocin-induced diabetes in rats.

Citrullus colocynthis (colocynth) seeds are traditionally used as antidiabetic medication in Mediterranean countries. The present study evaluated the differential effects of diets enriched with C. colocynthis, sunflower or olive oils on the pancreatic beta-cell mass in streptozotocin (STZ)-induced diabetes in rats. STZ injection induced rapid hyperglycaemia in all animals. However, 2 months later, hyperglycaemia was significantly less pronounced in the rats fed a C. colocynthis oil-enriched diet compared with other rat groups (7.9mM versus 12mM and 16mM with colocynth versus olive and sunflower oils, respectively). Assessment of insulin sensitivity using the homoeostasis model assessment (HOMA) method also indicated less insulin resistance in the rats fed a C. colocynthis oil-enriched diet versus the other rats. Finally, 2 months after STZ injection, the pancreatic beta-cell mass was similar in both the STZ-treated rats fed the colocynth oil-enriched diet and their controls fed the same diet. In contrast, the pancreatic beta-cell mass remained lower in the STZ-induced diabetic rats fed with olive oil- and sunflower oil-enriched diets compared with the C. colocynthis group. We conclude that C. colocynthis oil supplementation may have a beneficial effect by partly preserving or restoring pancreatic beta-cell mass in the STZ-induced diabetes rat model.

Improvement of metabolic state in an animal model of nutrition-dependent type 2 diabetes following treatment with S 23521, a new glucagon-like peptide 1 (GLP-1) analogue.

Glucagon-like peptide 1 (GLP-1) analogues are considered potential drugs for type 2 diabetes. We studied the effect of a novel GLP-1 analogue, S 23521 ([a8-des R36] GLP-1-[7-37]-NH2), on the metabolic state and beta-cell function, proliferation and survival in the Psammomys obesus model of diet-induced type 2 diabetes. Animals with marked hyperglycaemia after 6 days of high-energy diet were given twice-daily s.c. injection of 100 microg/kg S 23521 for 15 days. Food intake was significantly decreased in S 23251-treated P. obesus; however, there was no significant difference in body weight from controls. Progressive worsening of hyperglycaemia was noted in controls, as opposed to maintenance of pre-treatment glucose levels in the S 23521 group. Prevention of diabetes progression was associated with reduced mortality. In addition, the treated group had higher serum insulin, insulinogenic index and leptin, whereas plasma triglyceride and non-esterified fatty acid levels were decreased. S 23521 had pronounced effect on pancreatic insulin, which was 5-fold higher than the markedly depleted insulin reserve of control animals. Immunohistochemical analysis showed islet degranulation with disrupted morphology in untreated animals, whereas islets from S 23521-treated animals appeared intact and filled with insulin; beta-cell apoptosis was approximately 70% reduced, without a change in beta-cell proliferation. S 23521 treatment resulted in a 2-fold increase in relative beta-cell volume. Overall, S 23521 prevented the progression of diabetes in P. obesus with marked improvement of the metabolic profile, including increased pancreatic insulin reserve, beta-cell viability and mass. These effects are probably due to actions of S 23521 both directly on islets and via reduced food intake, and emphasize the feasibility of preventing blood glucose deterioration over time in type 2 diabetes.

Circulatory alterations induced by intra-arterial injection of iodized oil and emulsions of iodized oil and doxorubicin: experimental study.

PURPOSE: To evaluate circulatory alterations induced by intra-arterial injection of iodized oil and emulsions of iodized oil with an anticancer drug. MATERIALS AND METHODS: The viscosities and stability were evaluated in arterial flow of iodized oil and the emulsions. Doppler ultrasound was used to quantify the embolic effect in the arteries of rabbits. The behavior of doxorubicin and iodized oil in the rat cremaster muscle was studied with videomicroscopy. RESULTS: The emulsions did not break up after injection, and the size of discontinuous-phase droplets did not change. The embolic effect did not correlate with viscosity. The thinnest water-in-oil emulsion had the lowest embolic effect and induced homogeneous distribution of iodized oil droplets in the arterial tree. CONCLUSION: Changes in the formulation of emulsions obtained with the same proportions of drug and iodized oil change the distribution of iodized oil in the arterial tree, the location at which the drug is released, and the embolic effect.