Insulin therapy in people with type 2 diabetes: opportunities and challenges?

Given the continued interest in defining the optimal management of individuals with type 2 diabetes, the Editor of Diabetes Care convened a working party of diabetes specialists to examine this topic in the context of insulin therapy. This was prompted by recent new evidence on the use of insulin in such people. The group was aware of evidence that the benefits of insulin therapy are still usually offered late, and thus the aim of the discussion was how to define the optimal timing and basis for decisions regarding insulin and to apply these concepts in practice. It was noted that recent evidence had built upon that of the previous decades, together confirming the benefits and safety of insulin therapy, albeit with concerns about the potential for hypoglycemia and gain in body weight. Insulin offers a unique ability to control hyperglycemia, being used from the time of diagnosis in some circumstances, when metabolic control is disturbed by medical illness, procedures, or therapy, as well as in the longer term in ambulatory care. For those previously starting insulin, various other forms of therapy can be added later, which offer complementary effects appropriate to individual needs. Here we review current evidence and circumstances in which insulin can be used, consider individualized choices of alternatives and combination regimens, and offer some guidance on personalized targets and tactics for glycemic control in type 2 diabetes.

Magnitude and mechanisms of glucose counterregulation following islet transplantation in patients with type 1 diabetes suffering from severe hypoglycaemic episodes.

AIMS/HYPOTHESIS: Pancreatic islet transplantation stabilises glycaemic control in type 1 diabetes mellitus patients with neuroglycopoenia, despite them not achieving insulin independence because of limited graft function. However, the extent and underlying metabolic pathways of restored glucose counterregulation are unknown. We therefore compared systemic glucose turnover, including lactate gluconeogenesis (GN) and muscle glucose uptake, in individuals with type 1 diabetes who were transplant recipients with partial graft function (T1DM/ITx(+)), matched non-transplanted individuals with type 1 diabetes (T1DM/ITx(-)) and matched healthy non-diabetic individuals. METHODS: Participants (n = 12 in each group) underwent a euglycaemic and a hypoglycaemic (2.5-2.8 mmol/l) hyperinsulinaemic clamp (0.8 mU kg(-1) min(-1)) in a randomised crossover fashion. Systemic and skeletal muscle glucose and lactate kinetics were assessed using a combination of isotopic and forearm balance techniques. RESULTS: Whole-body glucose counterregulation, the difference in glucose infusion rates required to maintain the glycaemic goal between the hypoglycaemic and euglycaemic clamps, was improved in T1DM/ITx(+) (7.8 ± 1.3 µmol kg(-1) min(-1)) compared with T1DM/ITx(-) (0.3 ± 0.9 µmol kg(-1) min(-1)), but was ~45% lower than in controls (14.1 ± 2.1 µmol kg(-1) min(-1)). Increased endogenous glucose production (EGP) and decreased systemic glucose disposal accounted for 49% and 39% of glucose counterregulation in T1DM/ITx(+), respectively, compared with 60% and 36% in controls. Lactate GN increased in T1DM/ITx(+) (2.7 ± 0.4 µmol kg(-1) min(-1)) and controls (1.7 ± 0.5 µmol kg(-1) min(-1)), such that it accounted for 70% and 20% of the increased EGP, respectively. Skeletal muscle accounted for similar proportions of the decrease in systemic glucose disposal in controls (49%) and T1DM/ITx(+) (41%). CONCLUSIONS/INTERPRETATION: Partial islet graft function improves hypoglycaemia counterregulation by increasing EGP, largely via lactate GN and decreasing systemic glucose disposal. This may explain the reduction in severe hypoglycaemic events in T1DM/ITx(+) individuals. TRIAL REGISTRATION: ClinicalTrials.gov NCT01668485.

The role of adiponectin as a compensatory mediator for the primary secretory defect in latent autoimmune diabetes in adults.

BACKGROUND: Increased adiposity in patients with newly diagnosed type 2 diabetes mellitus (DM), as well as in patients who do not have DM, affects the regulation of insulin sensitivity and the metabolic effects of adiponectin. OBJECTIVE: The goal of this study was to investigate the relationship between plasma adiponectin levels and obesity in patients developing DM mainly due to an early decline in ß-cell function. METHODS: We studied 29 patients with latent autoimmune diabetes in adults (LADA), 38 patients with type 1 DM, and 55 healthy volunteers. RESULTS: Plasma adiponectin levels, adjusted for body mass index (BMI), were higher in patients with type 1 DM than in controls (P < 0.001) and similar to those in patients with LADA (P = 0.464). Plasma adiponectin levels were higher in LADA patients compared with controls (P < 0.001). In LADA patients, plasma adiponectin levels, adjusted for BMI, correlated significantly with insulin resistance (ß coefficient, -6.453 [2.772]; P = 0.028). Interestingly, this relationship in LADA patients was significant in more overweight patients (ß coefficient, -7.142 [3.249]; P = 0.048) but not in leaner patients (P = 0.571), a finding that was not confirmed through the results in the controls (P = 0.520 and P = 0.992, respectively). CONCLUSIONS: In patients with LADA, increases in plasma adiponectin levels, after adjustment for BMI, could act as a mediator for improvement in insulin sensitivity and thus compensate for the primary secretory defect. This effect seems more profound in more overweight subjects than in leaner subjects.

Diabetes mellitus secondary to pancreatic diseases (Type 3c)--are we neglecting an important disease?

Type 3c diabetes mellitus (T3cDM) is a clinically relevant condition with a prevalence of 5-10% among all diabetic subjects in Western populations. Its prevalence and clinical importance have been underestimated and underappreciated so far. In contrast to the management of type 1 or type 2 diabetes, the endocrinopathy in T3cDM is very complex and complicated by additional present comorbidities such as maldigestion and concommitant qualitative malnutrition. The failure to correctly diagnose T3cDM leads to failure to implement an appropriate medical therapy of these patients. Physicians should screen for important and easily reversable pathological conditions such as exocrine insufficiency, lack of fat-soluble vitamins (especially vitamin D) and impairment of fat hydrolysis and incretin secretion which are found very commonly in T3cDM. Since most patients with T3cDM suffer from chronic pancreatitis, physicians must additionally be aware of the elevated risk of pancreatic cancer in this subset of patients.

Reduced capacity of heart rate regulation in response to mild hypoglycemia induced by glibenclamide and physical exercise in type 2 diabetes.

OBJECTIVE: Decreased heart rate variability (HRV) is associated with enhanced mortality due to abnormal cardiac rhythm. While hypoglycemic events are increasingly common in the treatment of type 2 diabetes, HRV is part of the counter-regulation against low blood glucose levels. We hypothesized that HRV was impaired in mild hypoglycemia in diabetic individuals. MATERIALS/METHODS: Hyperinsulinemic-hypoglycemic clamps were performed in twelve type 2 diabetic patients without cardiovascular disease and in non-diabetic subjects matched for age, sex, and weight. In an additional study, hypoglycemic events, induced by either a single morning dose of glibenclamide or physical exercise, were recorded for the subsequent 24h. Blood glucose concentrations and electrocardiograms were continuously monitored. Serum hormone levels, hypoglycemic symptoms, and forearm blood flow were measured at defined time points. RESULTS: Occurrence of a symptomatic hypoglycemic episode (mean blood glucose 3.1±0.4 mmol/l) attenuated most of the time and frequency domain measurements in both healthy and diabetic individuals. The magnitude of reduction of HRV parameters was significantly lower in diabetic compared to healthy subjects. Glibenclamide taken in the morning enhanced the daily number of mild hypoglycemic events compared with placebo or moderate exercise. Concordantly, 24-h mean HRV measurements were decreased. CONCLUSION: HRV response to hypoglycemia is impaired in type 2 diabetic subjects resulting in a higher than expected risk for sudden arrhythmia following mild hypoglycemic episodes.

The emergence of biosimilar insulin preparations--a cause for concern?

Several biopharmaceuticals, including insulin and insulin analogs, are, or shortly will be, off-patent, thereby providing an opportunity for companies to attempt to manufacture "copies" commonly referred to as biosimilars and also known as follow-on biologics. Reassurance that such copy biologics are equally safe and effective as the conventional products is essential. It is important for the clinician to consider what information is therefore necessary for such assurances. Biopharmaceuticals, produced from living organisms and manufactured by complex processes, differ in many respects from chemically derived drugs. The biological source materials and manufacturing processes for non-innovator biologics may differ considerably from those used for producing the innovator substance. Differences between innovator and non-innovator products can be identified analytically (e.g., batch-to-batch consistency, product stability along side clinical safety). This provides a strong argument for caution before automatic substitution of conventional products (e.g., insulin by biosimilars). Several non-innovator insulins, including insulin analogs (while still patent-protected), are already available in many countries. Many of these lack rigorous regulations for biosimilar approval and pharmacovigilance. Recently an application for a biosimilar recombinant human insulin was withdrawn by the European Medicines Agency because of safety and efficacy concerns. Therefore, every biosimilar insulin and insulin analog should be assessed by well-defined globally harmonized preclinical and clinical studies followed by post-marketing pharmacovigilance programs, in the interest of people with diabetes worldwide.

Inhibition of gelatinase B (matrix metalloprotease-9) activity reduces cellular inflammation and restores function of transplanted pancreatic islets.

Islet transplantation provides an approach to compensate for loss of insulin-producing cells in patients with type 1 diabetes. However, the intraportal route of transplantation is associated with instant inflammatory reactions to the graft and subsequent islet destruction as well. Although matrix metalloprotease (MMP)-2 and -9 are involved in both remodeling of extracellular matrix and leukocyte migration, their influence on the outcome of islet transplantation has not been characterized. We observed comparable MMP-2 mRNA expressions in control and transplanted groups of mice, whereas MMP-9 mRNA and protein expression levels increased after islet transplantation. Immunostaining for CD11b (Mac-1)-expressing leukocytes (macrophage, neutrophils) and Ly6G (neutrophils) revealed substantially reduced inflammatory cell migration into islet-transplanted liver in MMP-9 knockout recipients. Moreover, gelatinase inhibition resulted in a significant increase in the insulin content of transplanted pancreatic islets and reduced macrophage and neutrophil influx compared with the control group. These results indicate that the increase of MMP-9 expression and activity after islet transplantation is directly related to enhanced leukocyte migration and that early islet graft survival can be improved by inhibiting MMP-9 (gelatinase B) activity.

Circulating cytokines are associated with human islet graft function in type 1 diabetes.

Islet cell transplantation has considerable potential as a cure for type 1 diabetes, but recurrent autoimmunity and allograft rejection in which both cytokines play an important role are major obstacles. Using a new approach considering confounders by regression analysis, we investigated circulating cytokines and their association with graft function in type 1 diabetes patients who underwent either simultaneous islet kidney (SIK) or islet after kidney (IAK) transplantation. After transplantation, interleukin (IL)-10 was lower in SIK recipients with subsequent loss of graft function in comparison to recipients maintaining graft function. Before transplantation, high IL-13 and IL-18 concentrations were prospectively associated for subsequent loss of graft function in IAK recipients, whereas in SIK recipients, high macrophage migration inhibitory factor (MIF) concentrations were associated with subsequent loss of graft function. Circulating cytokines are associated with islet graft function in patients with long-standing type 1 diabetes when considering confounders.

Successful treatment of severe hypertriglyceridemia with a formula diet rich in omega-3 fatty acids and medium-chain triglycerides.

BACKGROUND: Patients with highly increased plasma triglyceride levels are at risk of developing serious complications such as pancreatitis, coronary heart disease and stroke. Therefore it is important to rapidly decrease plasma triglyceride levels. A sufficient control of triglyceride levels with drugs like fibrates, statins or nicotinic acid can usually only be attained after a couple of weeks. Plasma exchange appears to be a fast but expensive method to reduce triglyceride levels. In this study we describe the use of a new omega-3 fatty acid and medium-chain triglyceride-rich formula diet as a therapeutic concept to reduce plasma triglyceride levels fast and effectively. METHODS: Thirty-two patients with severe hypertriglyceridemia were treated with the especially composed formula diet for a period of 7 days. RESULTS: Within this period of time, plasma triglycerides decreased from 1,601 (402-4,555) to 554 (142-2,382) mg/dl (p < 0.05). Total cholesterol levels were reduced from 417 (211-841) to 287 (165-457) mg/dl (p < 0.001). Fasting glucose and uric acid levels also slightly decreased (-8%; -12%). The formula diet as a 1-week treatment was well tolerated and accepted by the patients. CONCLUSION: This diet was successfully used as an acute treatment in severe hypertriglyceridemia and showed effectiveness in rapidly and safely lowering plasma triglyceride levels.

Immunomodulation with heat shock protein DiaPep277 to preserve beta cell function in type 1 diabetes - an update.

IMPORTANCE OF THE FIELD: Type 1 diabetes is a chronic autoimmune disease in which pancreatic beta cells are selectively destroyed. Ultimately hyperglycemia develops and insulin substitution becomes necessary. Immunomodulation aims at arresting this autoimmune attack. DiaPep277, the major T-cell epitope of heat shock protein 60 (hsp60), has been shown to be effective as a modulator of the immune system in type 1 diabetes and is the focus of this review. AREAS COVERED IN THIS REVIEW: A literature search of Pubmed listed publications covering 1990 - 2009 and a website search of the licensing company were performed. WHAT THE READER WILL GAIN: DiaPep277 has been successfully employed in animal models and has been investigated in Phase I - III studies in humans. A combined analysis of the Phase II trials showed a significant preservation of beta cell function in adults without adverse effects, but HbA1c was not changed. A Phase III clinical trial is ongoing, and a second Phase III trial will start in early 2010. Addressing the underlying autoimmune process is the call of the future in type 1 diabetes. TAKE HOME MESSAGE: Use of Diapep277 is a promising therapeutic strategy currently being tested in Phase III trials.

Anti-inflammatory thalidomide improves islet grafts survival and functions in a xenogenic environment.

Thalidomide possesses both anti-inflammatory and anti-angiogenic properties. This study investigates its potential application in islet transplantation with a xenogenic transplantation model. Transplantation was performed using C57Bl/6 mice and NMRI nu/nu mice as recipients of porcine islets. Moreover, islet graft vasculature and inflammation were investigated to identify the mechanisms of thalidomide action. In the immunocompetent environment of C57Bl/6 mice, a fast graft rejection was observed. The group treated with thalidomide 200 mg/kg BW per day achieved and maintained euglycemia in the complete observation period for 42 days. The treated mice had more functional islet graft mass with less leukocyte infiltration. The pro-inflammatory TNF-alpha and VEGF content in islet grafted kidneys was significantly lowered by the treatment. By comparison, thalidomide was not effective in improving graft survival in immunocompromised nude mice. It strongly inhibited the VEGF and TNF-alpha-induced endothelial proliferation of isolated pig islets in a dose dependent manner. The magnitude of thalidomide's inhibitory effect was nearly identical to the effect of VEGF- receptor 2 inhibitor SU416 and anti-TNF-receptor 1 neutralizing antibody, and was reversed by sphingosine-1-phosphate. In conclusion, the anti-inflammatory effect of thalidomide improved islet graft survival and function in a transplantation model with a maximum immune barrier.

Food derived carbonyl compounds affect basal and stimulated secretion of interleukin-6 and -8 in Caco-2 cells.

BACKGROUND: The carbonyl compounds methylglyoxal (MG) and glyoxal (G) are reactive intermediates generated in a variety of foods and beverages during processing and prolonged storage. AIM AND METHODS: We investigated direct effects of these compounds on intestinal cells determining the basal and stimulated secretion of IL-8 and IL-6 in vitro. RESULTS: MG or G induced a concentration dependent enhancement of IL-8 and IL-6 secretion compared to baseline levels. A co-incubation with pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) or lipopolysaccharides (LPS) and increasing MG concentrations further enhanced IL-8 and IL-6 secretion. For G, however, this additive effect was only observed in TNF-alpha and IL-1beta treated cells, but not after co-incubation with LPS. CONCLUSION: These results suggest a pro-inflammatory effect of G and MG at high concentrations in human intestinal cells by stimulating IL-8 and IL-6 cytokine levels. Effects of G and MG in combination with other cytokines may negatively affect inflammatory processes.

Comparison of treatment costs in inadequately controlled type 2 diabetes in Germany based on the APOLLO trial with insulin glargine.

OBJECTIVE: A cost analysis of once-daily insulin glargine versus three-times daily insulin lispro in combination with oral antidiabetic drugs (OADs) for insulin-naive type 2 diabetes patients in Germany based on the APOLLO trial (A Parallel design comparing an Oral antidiabetic drug combination therapy with either Lantus once daily or Lispro at mealtime in type 2 diabetes patients failing Oral treatment). METHODS: Annual direct treatment costs were estimated from the perspective of the German statutory health insurance (SHI). Costs accounted for included insulin medication, disposable pens and consumable items (needles, blood glucose test strips and lancets). Sensitivity analyses (on resource use and unit costs) were performed to reflect current German practice. RESULTS: Average treatment costs per patient per year in the base case were 1,073 euro for glargine and 1,794 euro for lispro. Insulin costs represented 65% vs. 37% of total costs respectively. Acquisition costs of glargine were offset by the lower costs of consumable items (380 euro vs. 1,139 euro). Sensitivity analyses confirmed the robustness of the results in favour of glargine. All scenarios yielded cost savings in total treatment costs ranging from 84 euro to 727 euro. CONCLUSIONS: Combination therapy of once-daily insulin glargine versus three-times daily insulin lispro both with OADs, in the management of insulin-dependent type 2 diabetes offers the potential for substantial cost savings from the German SHI perspective.

Activation of NFκB dependent apoptotic pathway in pancreatic islet cells by hypoxia.

Insulin producing ß-cells are exposed to hypoxic stress in the early period after islet transplantation. Although it has been suggested that hypoxia leads to islet loss, the underlying mechanisms are unclear. In this study, the early transcriptional profiles of b cell response to hypoxia were determined by using the Affymetrix Murine Genome Array U74Av2 GeneChip (about 12,422 genes). In addition to the upregulation of genes associated with glycolysis, genes related to apoptosis and stress response were also upregulated. The downregulated genes on hypoxia are classified as transcription and inflammatory response. These findings were confirmed by TUNEL assay and real-time reverse transcription-PCR for mRNA of genes related to apoptosis. On the other hand, we have found that the transcription factor NFκB was activated by hypoxia in islet cells. The affected genes involved in the activated NFκB pathway were mainly categorized as apoptosis-related genes by quantitative real-time PCR array (84 genes). Our comprehensive analysis of transcriptional changes of islets by hypoxia may assist the development of strategies that protect islet grafts from early loss.

Distinct autoantibodies against exocrine pancreatic antigens in European patients with type 1 diabetes mellitus and non-alcoholic chronic pancreatitis.

CONTEXT: Histopathological analysis has demonstrated lymphocytic infiltration in both the endocrine and the exocrine pancreas in some patients with type 1 diabetes and non-alcoholic chronic pancreatitis, suggesting an immune-mediated mechanism which affects both diabetes mellitus and chronic pancreatitis. OBJECTIVE: The examination of exocrine pancreatic humoral markers in Caucasian patients with respect to the interactions between exocrine and endocrine pancreatic diseases. PATIENTS: One hundred and thirty-six European Caucasian subjects subdivided into three groups: type 1 diabetes (n=48); non-alcoholic chronic pancreatitis (n=48); controls (n=40). MAIN OUTCOME MEASURE: Autoantibodies against carbonic anhydrase II (CAIIAb) and lactoferrin (LACAb) (both of which are exocrine pancreatic antigens) were analyzed by enzyme-linked immunosorbent assay. RESULTS: No positivity for CAIIAb and LACAb were found in the controls. Patients with type 1 diabetes had a significantly higher prevalence of CAIIAb (25.0%) than the controls while the prevalence of LACAb (8.3%) was not significantly higher than the controls. The prevalence of CAIIAb (12.5%) and LACAb (20.8%) in the patients with non-alcoholic chronic pancreatitis was significantly higher than that in the controls. A significantly higher prevalence of CAIIAb and/or LACAb was found in patients with type 1 diabetes (29.2%) and non-alcoholic chronic pancreatitis (22.9%) compared to that in the controls (0%). There was a significant association between CAIIAb and LACAb titers both in patients with type 1 diabetes (P=0.042) and in patients with non-alcoholic chronic pancreatitis (P<0.001). CONCLUSION: We have clearly demonstrated that some European Caucasian patients with type 1 diabetes and non-alcoholic chronic pancreatitis have autoantibodies against the exocrine pancreatic antigens CAIIAb and LACAb.

Effects of basswood honey, honey-comparable glucose-fructose solution, and oral glucose tolerance test solution on serum insulin, glucose, and C-peptide concentrations in healthy subjects.

Studies suggest that honey has less influence on serum glucose concentrations than monosaccharides and disaccharides. This study aimed to confirm these findings conclusively by comparing directly the effects of honey, an identical sugar solution, and oral glucose tolerance (OGT) test solution on serum glucose, insulin, and C-peptide values in healthy subjects. Twelve healthy men with a mean age of 27.7 years, a mean body mass index of 23.2 kg/m(2), and no history of metabolic disorders participated in the study. Subjects underwent OGT testing to establish values and exclude preclinical diabetes. One week later they were randomly assigned to basswood honey or a glucose-fructose solution (honey-comparable glucose-fructose solution). The following week subjects were given the other solution. All solutions contained 75 g of glucose. Serum glucose was measured before drinking test solutions and every 10 minutes for 120 minutes afterwards. C-peptide and insulin were measured at 60 and 120 minutes. Serum insulin and C-peptide values at 60 minutes were significantly lower for honey. The mean serum glucose concentration was also lower for honey, but direct comparisons at the various times showed no statistically significant differences between solutions. However, the area under the concentration-time profile for glucose response was lower for the honey than the honey-comparable glucose-fructose solution. Honey had less effect on serum glucose, C-peptide, and insulin values than the honey-comparable glucose-fructose solution. Further study to elucidate underlying mechanisms may be worthwhile, as may investigation of the implications of these findings for diabetic patients.

Nocturnal glucose metabolism after bedtime injection of insulin glargine or neutral protamine hagedorn insulin in patients with type 2 diabetes.

AIMS/HYPOTHESIS: Insulin glargine is a long-acting human insulin analog often administered at bedtime to patients with type 2 diabetes. It reduces fasting blood glucose levels more efficiently and with less nocturnal hypoglycemic events compared with human neutral protamine Hagedorn (NPH) insulin. Therefore, bedtime injections of insulin glargine and NPH insulin were compared overnight and in the morning. METHODS: In 10 type 2 diabetic patients, euglycemic clamps were performed, including [6,6'](2)H(2) glucose, to study the rate of disappearance (Rd) and endogenous production (EGP) of glucose during the night. On separate days at bedtime (2200 h), patients received a sc injection of insulin glargine, NPH insulin, or saline in a randomized, double-blind fashion. RESULTS: Similar doses of both insulins had different metabolic profiles. NPH insulin had a greater effect on both Rd and EGP in the night compared with insulin glargine. By contrast, in the morning, insulin glargine was more effective, increasing Rd by 5.8 micromol/kg(-1).min(-1) (95% confidence interval 4.7-6.9) and reducing EGP -5.7 (-5.0 to -6.4) compared with NPH insulin. Nearly 80% of the glucose lowering effect in the morning was due to insulin glargine's reduction of EGP. Its injection was associated with one-third lower morning glucagon levels compared with NPH insulin (P = 0.021). CONCLUSION/INTERPRETATION: Nocturnal variations of EGP and Rd explain the reduced incidence of hypoglycemia and lower fasting glucose levels reported for insulin glargine compared with human NPH insulin.