Omeprazole improves the anti‐obesity and antidiabetic effects of exendin‐4 in db/db mice (奥美拉唑改善唾液素‐4 对db/db小鼠的减肥与降糖作用)*

Background: In addition to its glucoregulatory actions, exendin‐4, a stable glucagon‐like peptide‐1 receptor agonist, exhibits protective effects in the pancreas and anti‐obesity effects. Suitable combination treatment with other anti‐obesity or pancreas protective agents would be an effective approach to optimize these additional effects. In the present study, we investigated the effects of the addition of omeprazole, a proton pump inhibitor, to exendin‐4 in db/db mice, an experimental model of obesity and type 2 diabetes. Methods: The effects repeated dose treatment for 14 days with exendin‐4 (8 μg/kg, s.c.) and omeprazole (30 mg/kg, s.c.) on glycemic control, food intake, and body weight were determined in obese and hyperglycemic db/db mice. The effects of these treatments on plasma gastrin, ghrelin, and leptin levels were determined, along with effects on nausea‐like symptoms. The pancreatic effects of the repeated dose treatment were assessed by measuring %HbA1c in the circulation as well as pancreatic insulin and glucagon content and glucokinase activity. Results: Combination treatment resulted in significant decreases in plasma leptin and ghrelin levels after repeated dosing. Omeprazole improved the anorectic and body weight‐lowering effects and reversed the inhibitory effect of exendin‐4 on gastrin levels after repeated dose treatment. The 14‐day combination treatment significantly reduced glucose excursion and improved insulin levels, with a concomitant decrease in %HbA1c levels. It also improved glucokinase activity and pancreatic insulin content, with a significant decrease in glucagon content. Conclusions: Combined treatment with omeprazole with exendin‐4 reduces food intake and body weight gain, most likely through changes in plasma ghrelin and leptin levels, and improves pancreatic insulin and glucagon content by improving glucokinase activity.     

Who needs an artificial pancreas? (怎样的患者需要一个人工胰腺？)

The development of a closed‐loop “artificial pancreas” would be a welcome advance for both endocrinologists and diabetic patients struggling to attain near normal glycemic control. While great strides in automatically controlling blood sugar in the fasting, sedentary state have been made through complex mathematical modeling, management of blood sugar excursions due to food and exercise have been more problematic. An artificial pancreas is not feasible at this time because of limitations inherent in the currently available technology.     

Current role of short‐term intensive insulin strategies in newly diagnosed type 2 diabetes (短期胰岛素强化治疗策略对初诊2型糖尿病患者的作用)

Type 2 diabetes mellitus (T2DM) is a progressive disease characterized by worsening insulin resistance and a decline in β‐cell function. Achieving good glycemic control becomes more challenging as β‐cell function continues to deteriorate throughout the disease process. The traditional management paradigm emphasizes a stepwise approach, and insulin has generally been reserved as a final armament. However, mounting evidence indicates that short‐term intensive insulin therapy used in the early stages of type 2 diabetes could improve β‐cell function, resulting in better glucose control and more extended glycemic remission than oral antidiabetic agents. Improvements in insulin sensitivity and lipid profile were also seen after the early initiation of short‐term intensive insulin therapy. Thus, administering short‐term intensive insulin therapy to patients with newly diagnosed T2DM has the potential to delay the natural process of this disease, and should be considered when clinicians initiate treatment. Although the early use of insulin is advocated by some guidelines, the optimal time to initiate insulin therapy is not clearly defined or easily recognized, and a pragmatic approach is lacking. Herein we summarize the current understanding of early intensive insulin therapy in patients with newly diagnosed T2DM, focusing on its clinical benefit and problems, as well as possible biological mechanisms of action, and discuss our perspective.     

FoxO6 in glucose metabolism (FoxO6在葡萄糖代谢中的作用)

The forkhead box O (FoxO) subfamily has four members, namely FoxO1, FoxO3, FoxO4, and FoxO6. Unlike the other three members of the FoxO family, FoxO6 has garnered considerably less attention because of earlier reports that FoxO6 expression was limited to the brain. Recent data indicate that FoxO6 is produced in the liver of both rodents and humans. Hepatic FoxO6 activity, which remains at low basal levels in fed states, is markedly induced in fasted mice. FoxO6 activity becomes abnormally higher in the liver of mice with dietary obesity or type 2 diabetes (T2D). Genetically engineered mice with elevated FoxO6 activity in the liver exhibit prediabetes, culminating in the development of glucose intolerance, fasting hyperglycemia, and hyperinsulinemia. Conversely, inhibition of FoxO6 activity in the insulin‐resistant liver results in a reduction in fasting hyperglycemia, contributing to the amelioration of hyperinsulinemia in T2D mice. These new data suggest that FoxO6 is an important regulator of hepatic glucose metabolism in response to insulin or physiological cues. Insulin inhibits FoxO6 activity by promoting its phosphorylation and disabling its activity in the nucleus without altering its subcellular distribution via a mechanism that is distinct from other members of the FoxO subfamily. In this article, we comprehensively review the role of FoxO6 in glucose metabolism in health and disease. We also address whether FoxO6 dysregulation is a contributing factor for the pathogenesis of fasting hyperglycemia and discuss whether FoxO6 is a potential therapeutic target for improving fasting hyperglycemia in T2D.     

Diabetes and cancer relationships (糖尿病与肿瘤的关联性)

Diabetes and cancer are both heterogeneous and multifactorial diseases with tremendous impact on health worldwide. Epidemiologic evidence suggests that certain malignancies may be associated with diabetes, as well as with diabetes risk factors and, perhaps, with certain diabetes treatments. Numerous biological mechanisms could account for these relationships. Insulin‐like growth factor (IGF)‐1, IGF‐2, IGF‐1 receptors, insulin, and the insulin receptor play roles in the development and progression of cancers. Although evidence from randomized controlled trials does not support or refute associations of diabetes and its treatments with either increased or reduced risk of cancer incidence or prognosis, consideration of malignancy incidence rates and the magnitude of the trials that would be required to address these issues explains why such studies may not be readily undertaken.     

Hypoglycemia in diabetes: The dark side of diabetes treatment. A patient‐centered review

Hypoglycemia is a frequent occurrence in patients with diabetes who are treated with insulin and insulin secretagogues. Hypoglycemia is the limiting factor that prevents patients from achieving the glycemic control known to reduce the microvascular complications of diabetes. Recurrent episodes of hypoglycemia can lead to impaired awareness of hypoglycemia where the first symptom of a low blood sugar is unconsciousness. The fear of hypoglycemia has a significant effect on the quality of life of patients and their families. In the acute setting, hypoglycemia can kill, and clinical trials have demonstrated that a single episode of severe hypoglycemia increases the risk of subsequent mortality and cardiovascular events. Clinicians must make efforts to recognize and prevent hypoglycemia in order to prevent the adverse events associated with this event. Patient education is central to these efforts. Recent developments in glucose monitoring and drug development have provided more approaches that can be used to reduce the risk of hypoglycemia in patients with diabetes.