Diabetes & metabolism
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Diabetes & metabolism · Sep 2003
ReviewMitochondrial metabolism and type-2 diabetes: a specific target of metformin.
Several links relate mitochondrial metabolism and type 2 diabetes or chronic hyperglycaemia. Among them, ATP synthesis by oxidative phosphorylation and cellular energy metabolism (ATP/ADP ratio), redox status and reactive oxygen species (ROS) production, membrane potential and substrate transport across the mitochondrial membrane are involved at various steps of the very complex network of glucose metabolism. Recently, the following findings (1) mitochondrial ROS production is central in the signalling pathway of harmful effects of hyperglycaemia, (2) AMPK activation is a major regulator of both glucose and lipid metabolism connected with cellular energy status, (3) hyperglycaemia by inhibiting glucose-6-phosphate dehydrogenase (G6PDH) by a cAMP mechanism plays a crucial role in NADPH/NADP ratio and thus in the pro-oxidant/anti-oxidant cellular status, have deeply changed our view of diabetes and related complications. ⋯ However, recent important findings may explain its unique efficacy in the treatment of hyperglycaemia- or insulin-resistance related complications. Metformin is a mild inhibitor of respiratory chain complex 1; it activates AMPK in several models, apparently independently of changes in the AMP-to-ATP ratio; it activates G6PDH in a model of high-fat related insulin resistance; and it has antioxidant properties by a mechanism (s), which is (are) not completely elucidated as yet. Although it is clear that metformin has non-mitochondrial effects, since it affects erythrocyte metabolism, the mitochondrial effects of metformin are probably crucial in explaining the various properties of this drug.
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Diabetes & metabolism · Sep 2003
Editorial ReviewIs metformin more than an oral hypoglycaemic agent?
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Diabetes & metabolism · Dec 2002
Review Comparative StudyNew antiobesity agents in type 2 diabetes: overview of clinical trials with sibutramine and orlistat.
Besides genetic predisposition, obesity is the most important risk factor for the development of type 2 diabetes mellitus. Even modest weight reduction can improve blood glucose control in overweight subjects. After failure of lifestyle modifications, antiobesity drugs such as orlistat, a potent and selective inhibitor of gastric and pancreatic lipases that reduces lipid intestinal absorption, or sibutramine, a noradrenaline and 5-hydroxytryptamine reuptake inhibitor that regulates food intake, may be considered to favour weight loss and/or weight maintenance. ⋯ In addition, vascular risk factors associated to insulin resistance were also reduced after weight loss. These antiobesity agents may also contribute to delay or prevent the progression from impaired glucose tolerance to overt type 2 diabetes in at risk obese individuals ("Xenical in the prevention of diabetes in obese subjects" trial). Large long-term prospective studies, such as the "Sibutramine cardiovascular and diabetes outcome study" should better determine the place of pharmacological anti-obesity strategy in the overall management of obese patients with impaired glucose tolerance or type 2 diabetes.
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Diabetes & metabolism · Dec 2002
Comparative StudyDiagnosis of osteomyelitis in the diabetic foot with a 99mTc-HMPAO leucocyte scintigraphy combined with a 99mTc-MDP bone scintigraphy.
The aim of this prospective study was to assess the role of 99mTc-HMPAO leucocyte scintigraphy combined with a 99mTc-MDP bone scintigraphy in the diagnosis of the diabetic foot infection (HMPAO-Leu/MDP). ⋯ With a sensitivity of 92.6%, a specificity of 97.6%, the HMPAO-Leu/MDP scan is a reliable tool for the diagnosis of osteomyelitis in the diabetic foot. Neuroarthropathy did not affect the performances of the HMPAO-Leu/MDP scan. Owing to a high spatial resolution this test is very helpful to differentiate bone infection from soft-tissue infection especially in case of neuroarthropathy.
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Diabetes & metabolism · Sep 2002
Randomized Controlled Trial Clinical TrialCombination-therapy with bedtime nph insulin and sulphonylureas gives similar glycaemic control but lower weight gain than insulin twice daily in patients with type 2 diabetes.
To study the effect on body weight and glycaemic control of two insulin treatment regimens in patients with Type 2 diabetes and moderate failure to oral hypoglycaemic agents. ⋯ Both treatments improved glycaemic control to the same extent but the combination of bedtime NPH insulin and daytime sulphonylurea gave a very small increase of body weight over a 6 months period. We conclude that combination therapy is an attractive alternative when starting insulin treatment in patients with Type 2 diabetes as this is a critical period for weight gain in such patients.