Mark N. Feinglos

Diet-Induced Type II Diabetes in C57BL/6J Mice

We investigated the effects of diet-induced obesity on glucose metabolism in two strains of mice, C57BL/6J and A/J. Twenty animals from each strain received ad libitum exposure to a high–fat high-simple-carbohydrate diet or standard Purina Rodent Chow for 6 mo. Exposure to the high-fat, high-simple-carbohydrate, low-fiber diet produced obesity in both A/J and C57BL/6J mice. Whereas obesity was associated with only moderate glucose intolerance and insulin resistance in A/J mice, obese C57BL/6J mice showed clear-cut diabetes with fasting blood glucose levels of >240 mg/dl and blood insulin levels of >150 μU/ml. C57BL/6J mice showed larger glycemic responses to stress and epinephrine in the lean state than AJ mice, and these responses were exaggerated by obesity. These data suggest that the C57BL/6J mouse carries a genetic predisposition to develop non-insulin-dependent (type II) diabetes. Futhermore, altered glycemic response to adrenergic stimulation may be a biologic marker for this genetic predisposition to develop type II diabetes.

Differential effects of fat and sucrose on the development of obesity and diabetes in C57BL/6J and A/J mice

We have previously demonstrated that the C57BL/6J (B/6J) mouse will develop severe obesity, hyperglycemia, and hyperinsulinemia if weaned onto a high-fat, high-sucrose (HH) diet. In the present study, we compared the effects of fat and sucrose separately and in combination on diabetes- and obesity-prone B/6J and diabetes- and obesity-resistant A/J mice. After 4 months, the feed efficiency ([FE] weight gained divided by calories consumed) did not differ across diets in A/J mice, but B/6J mice showed a significantly increased FE for fat. That is, B/6J mice gained more weight on high-fat diets without consuming more calories than A/J mice. The increase in FE was related to adipocyte hyperplasia in B/6J mice on high-fat diets. Fat-induced obesity in B/6J mice was unrelated to adrenal cortical activity. In the absence of fat, sucrose produced a decreased in FE in both strains. Animals fed a low-fat, high-sucrose (LH) diet were actually leaner than animals fed a high-complex-carbohydrate diet. Fat was also found to be the critical stimulus for hyperglycemia and hyperinsulinemia in B/6J mice. In the absence of fat, sucrose had no effect on plasma glucose or insulin. These data clearly show that across these two strains of mice, genetic differences in the metabolic response to fat are more important in the development of obesity and diabetes than the increased caloric content of a high-fat diet.

The effects of baseline characteristics, glycaemia treatment approach, and glycated haemoglobin concentration on the risk of severe hypoglycaemia: post hoc epidemiological analysis of the ACCORD study

Objectives To investigate potential determinants of severe hypoglycaemia, including baseline characteristics, in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial and the association of severe hypoglycaemia with levels of glycated haemoglobin (haemoglobin A1C) achieved during therapy. Design Post hoc epidemiological analysis of a double 2×2 factorial, randomised, controlled trial. Setting Diabetes clinics, research clinics, and primary care clinics. Participants 10 209 of the 10 251 participants enrolled in the ACCORD study with type 2 diabetes, a haemoglobin A1C concentration of 7.5% or more during screening, and aged 40-79 years with established cardiovascular disease or 55-79 years with evidence of significant atherosclerosis, albuminuria, left ventricular hypertrophy, or two or more additional risk factors for cardiovascular disease (dyslipidaemia, hypertension, current smoker, or obese). Interventions Intensive (haemoglobin A1C <6.0%) or standard (haemoglobin A1C 7.0-7.9%) glucose control. Main outcome measures Severe hypoglycaemia was defined as episodes of “low blood glucose” requiring the assistance of another person and documentation of either a plasma glucose less than 2.8 mmol/l (<50 mg/dl) or symptoms that promptly resolved with oral carbohydrate, intravenous glucose, or glucagon. Results The annual incidence of hypoglycaemia was 3.14% in the intensive treatment group and 1.03% in the standard glycaemia group. We found significantly increased risks for hypoglycaemia among women (P=0.0300), African-Americans (P<0.0001 compared with non-Hispanic whites), those with less than a high school education (P<0.0500 compared with college graduates), aged participants (P<0.0001 per 1 year increase), and those who used insulin at trial entry (P<0.0001). For every 1% unit decline in the haemoglobin A1C concentration from baseline to 4 month visit, there was a 28% (95% CI 19% to 37%) and 14% (4% to 23%) reduced risk of hypoglycaemia requiring medical assistance in the standard and intensive groups, respectively. In both treatment groups, the risk of hypoglycaemia requiring medical assistance increased with each 1% unit increment in the average updated haemoglobin A1C concentration (standard arm: hazard ratio 1.76, 95% CI 1.50 to 2.06; intensive arm: hazard ratio 1.15, 95% CI 1.02 to 1.21). Conclusions A greater drop in haemoglobin A1C concentration from baseline to the 4 month visit was not associated with an increased risk for hypoglycaemia. Patients with poorer glycaemic control had a greater risk of hypoglycaemia, irrespective of treatment group. Identification of baseline subgroups with increased risk for severe hypoglycaemia can provide guidance to clinicians attempting to modify patient therapy on the basis of individual risk. Trial registration ClinicalTrials.gov number NCT00000620.

Stress and Diabetes Mellitus

Stress is a potential contributor to chronic hyperglycemia in diabetes. Stress has long been shown to have major effects on metabolic activity. Energy mobilization is a primary result of the fight or flight response. Stress stimulates the release of various hormones, which can result in elevated blood glucose levels. Although this is of adaptive importance in a healthy organism, in diabetes, as a result of the relative or absolute lack of insulin, stress-induced increases in glucose cannot be metabolized properly. Furthermore, regulation of these stress hormones may be abnormal in diabetes. However, evidence characterizing the effects of stress in type I diabetes is contradictory. Although some retrospective human studies have suggested that stress can precipitate type I diabetes, animal studies have shown that stressors of various kinds can precipitate—or prevent—various experimental models of the disease. Human studies have shown that stress can stimulate hyperglycemia, hypoglycemia, or have no affect at all on glycemic status in established diabetes. Much of this confusion may be attributable to the presence of autonomic neuropathy, common in type I diabetes. In contrast, more consistent evidence supports the role of stress in type II diabetes. Although human studies on the role of stress in the onset and course of type II diabetes are few, a large body of animal study supports the notion that stress reliably produces hyperglycemia in this form of the disease. Furthermore, there is mounting evidence of autonomic contributions to the pathophysiology of this condition in both animals and humans.

Once-weekly albiglutide versus once-daily liraglutide in patients with type 2 diabetes inadequately controlled on oral drugs (HARMONY 7): a randomised, open-label, multicentre, non-inferiority phase 3 study

BACKGROUND As new members of a drug class are developed, head-to-head trials are an important strategy to guide personalised treatment decisions. We assessed two glucagon-like peptide-1 receptor agonists, once-weekly albiglutide and once-daily liraglutide, in patients with type 2 diabetes inadequately controlled on oral antidiabetic drugs. METHODS We undertook this 32-week, open-label, phase 3 non-inferiority study at 162 sites in eight countries: USA (121 sites), Australia (9 sites), Peru (7 sites), Philippines (7 sites), South Korea (5 sites), UK (5 sites), Israel (4 sites), and Spain (4 sites). 841 adult participants (aged ≥18 years) with inadequately controlled type 2 diabetes and a BMI between 20 and 45 kg/m(2) were enrolled and randomised in a 1:1 ratio to receive albiglutide 30 mg once weekly titrated to 50 mg at week 6, or liraglutide 0·6 mg once daily titrated to 1·2 mg at week 1 and 1·8 mg at week 2. The randomisation schedule was generated by an independent randomisation team by the permuted block method with a fixed block size of 16. Participants and investigators were unmasked to treatment. The primary endpoint was change from baseline in HbA1c for albiglutide versus liraglutide, with a 95% CI non-inferiority upper margin of 0·3%. The primary analysis was by modified intention to treat. The study is registered with ClinicalTrials.gov, number NCT01128894. FINDINGS 422 patients were randomly allocated to the albigultide group and 419 to the liraglutide group; 404 patients in the abliglutide group and 408 in the liraglutide group received the study drugs. The primary endpoint analysis was done on the modified intention-to-treat population, which included 402 participants in the albiglutide group and 403 in the liraglutide group. Model-adjusted change in HbA1c from baseline to week 32 was -0·78% (95% CI -0·87 to -0·69) in the albigludite group and -0·99% (-1·08 to -0·90) in the liraglutide group; treatment difference was 0·21% (0·08-0·34; non-inferiority p value=0·0846). Injection-site reactions occurred in more patients given albiglutide than in those given liraglutide (12·9% vs 5·4%; treatment difference 7·5% [95% CI 3·6-11·4]; p=0·0002), whereas the opposite was the case for gastrointestinal events, which occurred in 49·0% of patients in the liraglutide group versus 35·9% in the albiglutide group (treatment difference -13·1% [95% CI -19·9 to -6·4]; p=0·00013). INTERPRETATION Patients who received once-daily liraglutide had greater reductions in HbA1c than did those who received once-weekly albiglutide. Participants in the albiglutide group had more injection-site reactions and fewer gastrointestinal events than did those in the liraglutide group. FUNDING GlaxoSmithKline.

Reversal of diet-induced obesity and diabetes in C57BL/6J mice.

We have previously shown that C57BL/6J (B6) mice develop severe obesity and diabetes if weaned onto high-fat diets, whereas A/J mice tend to be obesity and diabetes-resistant. The purpose of this study was to determine if obesity and diabetes in the B6 mouse could be completely reversed by reducing dietary fat content. After 4 months, both strains consumed more calories on a high-fat diet than on a low-fat diet, and both strains showed a higher feed efficiency (FE=weight gained/calories consumed) on the high-fat diet versus the low-fat diet. However, relative to A/J mice, B6 mice demonstrated a significantly higher FE on the high-fat diet. Hyperglycemia, hyperinsulinemia, and increased adiposity were apparent in B6 mice after 4 months on the high-fat diet regardless of whether the diet was begun at weaning or 4 months later. Correlational analyses showed that adiposity was strongly related to both insulin and glucose levels in B6 mice, but only moderately related to insulin levels in A/J mice. In obese B6 mice that were switched to a low-fat diet, obesity and diabetes were completely reversed. Adiposity, fasting glucose, and fasting insulin values in these mice were equivalent to those in B6 mice of the same age that had spent 8 months on the low-fat diet. In summary, our data show that in the B6 mouse the severity of diabetes is a direct function of obesity and diabetes is completely reversible by reducing dietary fat.

The Growing Burden of Diabetes Mellitus in the US Elderly Population

BACKGROUND The prevalence of diabetes mellitus is growing worldwide. Consequently, there has been increased emphasis on primary and secondary prevention of diabetes. To our knowledge, whether there have been actual improvements in outcomes in the last decade or so has not been documented in a nationally representative sample. METHODS We undertook this study to examine trends in rates of occurrence of diabetes and its complications in persons older than 65 years in the United States. National longitudinal analysis of Medicare claims and other Medicare program data for persons first diagnosed as having diabetes during 1994 (n=33 164), 1999 (n=31 722), or 2003 (n=40 058) were compared with 2 control groups of persons of approximately equal sample size who were not diagnosed as having diabetes, alternatively during 1994, 1999, or 2003 or for the entire period from 1994 to 1999 or from 1999 to 2004. The main outcome measures were death and complications of diabetes including cardiovascular, cerebrovascular, ophthalmic, renal, and lower extremity events. RESULTS The annual incidence of diabetes increased by 23% between 1994-1995 and 2003-2004, and prevalence increased by 62%. The mortality rate after diagnosis in persons having diagnosed diabetes decreased by 8.3% compared with that in the control groups. Complication rates among persons diagnosed as having diabetes generally increased or stayed the same compared with those in the control groups during 1994 to 2004 except for ophthalmic diseases associated with diabetes. Rates for some major complications were high; for example, the rate for congestive heart failure in the diabetes group during 1999 to 2004 was 475 per 1000 persons. In some cases, most notably renal events, including the most serious complications, there were increases in prevalence in both the diabetes and control groups. CONCLUSION The burden of financing and providing medical care for persons older than 65 in the United States having diagnosed diabetes is growing rapidly as a result of increased incidence and, especially, prevalence of diagnosed diabetes, decreased mortality, and overall lack of improvement in rates of complications in persons having diagnosed diabetes.

Effects of liraglutide (NN2211), a long-acting GLP-1 analogue, on glycaemic control and bodyweight in subjects with Type 2 diabetes

Aims  Liraglutide (NN2211) is a long‐acting GLP‐1 analogue, with a pharmacokinetic profile suitable for once‐daily administration. This multicentre, double‐blind, parallel‐group, double‐dummy study explored the dose–response relationship of liraglutide effects on bodyweight and glycaemic control in subjects with Type 2 diabetes.

Osteomalacia Due to 1α,25-Dihydroxycholecalciferol Deficiency: ASSOCIATION WITH A GIANT CELL TUMOR OF BONE

Oncogenic osteomalacia is a syndrome in which unexplained osteomalacia remits after resection of a coexisting mesenchymal tumor. We have investigated the mechanism by which a giant cell tumor of bone caused biopsy-proved osteomalacia in a 42-yr-old woman. The biochemical abnormalities were: hypophosphatemia; decreased renal tubular maximum for the reabsorption of phosphate per liter of glomerular filtrate; negative calcium and phosphorus balance; hyperaminoaciduria; and subnormal calcemic response to exogenously administered parathyroid hormone. Malabsorption, hypophosphatasia, fluorosis, and acidosis were excluded as causes of the osteomalacia. Serum 25-hydroxycholecalciferol was normal (27+/-1 ng/ml). However, the serum concentration of 1alpha,25-dihydroxycholecalciferol was low (1.6+/-0.1 ng/100 ml). Oral administration of physiological amounts of 1alpha,25-dihydroxycholecalciferol resulted in resolution of the biochemical abnormalities of the syndrome and healing of the bone pathology. We suggest that tumor-induced inhibition of 1alpha,25-dihydroxycholecalciferol synthesis caused the osteomalacia. The causal role of the tumor was proved by demonstrating that resection was accompanied by roentgenographic evidence of bone healing and maintenance of normal serum phosphorus; renal tubular maximum for the reabsorption of phosphate; calcium and phosphorus balance; aminoaciduria; and calcemic response to exogenous parathyroid hormone.

HARMONY 3: 104-week randomized, double-blind, placebo- and active-controlled trial assessing the efficacy and safety of albiglutide compared with placebo, sitagliptin, and glimepiride in patients with type 2 diabetes taking metformin.

OBJECTIVE To compare the efficacy and safety of weekly albiglutide with daily sitagliptin, daily glimepiride, and placebo. Research Design And Methods Patients with type 2 diabetes receiving metformin were randomized to albiglutide (30 mg), sitagliptin (100 mg), glimepiride (2 mg), or placebo. Blinded dose titration for albiglutide (to 50 mg) and glimepiride (to 4 mg) was based on predefined hyperglycemia criteria. The primary end point was change in HbA1c from baseline at week 104. Secondary end points included fasting plasma glucose (FPG), weight, and time to hyperglycemic rescue. RESULTS Baseline characteristics were similar among the albiglutide (n = 302), glimepiride (n = 307), sitagliptin (n = 302), and placebo (n = 101) groups. Baseline HbA1c was 8.1% (65.0 mmol/mol); mean age was 54.5 years. The mean doses for albiglutide and glimepiride at week 104 were 40.5 and 3.1 mg, respectively. At week 104, albiglutide significantly reduced HbA1c compared with placebo (−0.9% [−9.8 mmol/mol]; P < 0.0001), sitagliptin (−0.4% [−4.4 mmol/mol]; P = 0.0001), and glimepiride (−0.3% [−3.3 mmol/mol]; P = 0.0033). Outcomes for FPG and HbA1c were similar. Weight change from baseline for each were as follows: albiglutide −1.21 kg (95% CI −1.68 to −0.74), placebo −1.00 kg (95% CI −1.81 to −0.20), sitagliptin −0.86 kg (95% CI −1.32 to −0.39), glimepiride 1.17 kg (95% CI 0.70–1.63). The difference between albiglutide and glimepiride was statistically significant (P < 0.0001). Hyperglycemic rescue rate at week 104 was 25.8% for albiglutide compared with 59.2% (P < 0.0001), 36.4% (P = 0.0118), and 32.7% (P = 0.1504) for placebo, sitagliptin, and glimepiride, respectively. Rates of serious adverse events in the albiglutide group were similar to comparison groups. Diarrhea (albiglutide 12.9%, other groups 8.6–10.9%) and nausea (albiglutide 10.3%, other groups 6.2–10.9%) were generally the most frequently reported gastrointestinal events. CONCLUSIONS Added to metformin, albiglutide was well tolerated; produced superior reductions in HbA1c and FPG at week 104 compared with placebo, sitagliptin, and glimepiride; and resulted in weight loss compared with glimepiride.