Cholecystokinin (CCK) decreases meal size through activation of CCK-A receptors on vagal afferents. We tested the hypothesis that the selective CCK-A agonist GI181771X induces weight loss in obese patients. Patients with body mass index > or = 30 or > or = 27 kg/m2 with concomitant risk factors were randomized to 24-week, double-blind treatment with different GI181771X doses or matching placebo together with a hypocaloric diet. The primary efficacy end point was the absolute change in body weight. To monitor pancreatic and gallbladder effects, patients underwent abdominal ultrasound and magnetic resonance imaging before and after treatment. We randomized 701 patients to double-blind treatment. GI181771X did not reduce body weight and had no effect on waist circumference or other cardiometabolic risk markers. Gastrointestinal side effects were more common with GI181771X than with placebo treatment, whereas hepatobiliary or pancreatic abnormalities did not occur. CCK-A by itself does not have a central role in long-term energy balance.

Consistency in the amount and source of carbohydrate intake from day-to-day is associated with improved blood glucose control in people with type 1 diabetes, a result which supports continued educational efforts to achieve adherence to a diabetes diet plan. This conclusion may not apply to people on intensified insulin therapy who adjust their insulin dose based on their actual carbohydrate intake at each meal.

Type 2 diabetes is caused by progressively increasing insulin resistance coupled with deteriorating beta-cell function, and there is a growing body of evidence to suggest that both of these defects precede hyperglycaemia by many years. Several studies have demonstrated the importance of maintaining beta-cell function in patients with Type 2 diabetes. This review explores parameters used to indicate beta-cell dysfunction, in Type 2 diabetes and in individuals with a predisposition to the disease. A genetic element undoubtedly underlies beta-cell dysfunction; however, a number of modifiable components are also associated with beta-cell deterioration, such as chronic hyperglycaemia and elevated free fatty acids. There is also evidence for a link between pro-inflammatory cytokines and impairment of insulin-signalling pathways in the beta-cell, and the potential role of islet amyloid deposition in beta-cell deterioration continues to be a subject for debate. The thiazolidinediones are a class of agents that have demonstrated clinical improvements in indices of beta-cell dysfunction and have the potential to improve beta-cell function. Data are accumulating to show that this therapeutic group offers a number of advantages over traditionally employed oral agents, and these data demonstrate the growing importance of thiazolidinediones in Type 2 diabetes management.