Current role of short-term intensive insulin strategies in newly diagnosed type 2 diabetes

Caveolin-1 Is Essential for the Improvement of Insulin Sensitivity through AKT Activation during Glargine Treatment on Diabetic Mice

Insulin treatment was confirmed to reduce insulin resistance, but the underlying mechanism remains unknown. Caveolin-1 (Cav-1) is a functional protein of the membrane lipid rafts, known as caveolae, and is widely expressed in mammalian adipose tissue. There is increasing evidence that show the involvement of Cav-1 in the AKT activation, which is responsible for insulin sensitivity. Our aim was to investigate the effect of Cav-1 depletion on insulin sensitivity and AKT activation in glargine-treated type 2 diabetic mice. Mice were exposed to a high-fat diet and subject to intraperitoneal injection of streptozotocin to induce diabetes. Next, glargine was administered to treat T2DM mice for 3 weeks (insulin group). The expression of Cav-1 was then silenced by injecting lentiviral-vectored short hairpin RNA (shRNA) through the tail vein of glargine-treated T2DM mice (CAV1-shRNA group), while scramble virus injection was used as a negative control (Ctrl-shRNA group). The results showed that glargine was able to upregulate the expression of PI3K and activate serine phosphorylation of AKT through the upregulation of Cav-1 expression in paraepididymal adipose tissue of the insulin group. However, glargine treatment could not activate AKT pathway in Cav-1 silenced diabetic mice. These results suggest that Cav-1 is essential for the activation of AKT and improving insulin sensitivity in type 2 diabetic mice during glargine treatment.

Effect of short-term intensive insulin therapy on α-cell function in patients with newly diagnosed type 2 diabetes

The effect of intensive insulin therapy on hyperglucagonemia in newly diagnosed type 2 diabetes (T2DM), and its associations with β-cell function, has not been elucidated. This study assessed the effect of 12 weeks of intensive insulin therapy on hyperglucagonemia in newly diagnosed T2DM and its associations with β-cell function, with reference to the effects of 12 weeks of oral hypoglycemic agents (OHAs).One hundred eight patients with newly diagnosed T2DM were enrolled from January 2015 to December 2015. The patients were randomly divided to receive, for 12 weeks, either intensive insulin therapy or OHAs. Meal tolerance tests were conducted at baseline before treatment (0 week), at 12 weeks (end of treatment), and 12 months after the initiation of treatment. The levels of glucagon, proinsulin, C-peptide (CP), and blood glucose were measured at timepoints 0, 30, and 120 minutes during the meal tolerance test.Intensive insulin treatment was associated with a decrease in glucagon levels (at 0, 30, and 120 minutes) and proinsulin/CP, and an increase in the insulin-secretion index ΔCP30/ΔG30 and ΔCP120/ΔG120, at 12 weeks and 12 months during the follow-up, compared with the corresponding effects of OHAs. Intensive insulin therapy could reduce but failed to normalize glucagon levels at 12 weeks. There were no correlations between the change of percentages in total area under the curve of glucagon and other glycemic parameters (proinsulin/CP; ΔCP30/ΔG30; or ΔCP120/ΔG120). Patients who received intensive insulin therapy were more likely to achieve their target glycemic goal and remission, compared with those who received OHAs.Short-term intensive insulin therapy facilitates the improvement of both β-cell and α-cell function in newly diagnosed T2DM mellitus. Decline of β-cell secretion and concomitant α-cell dysfunction may both be involved in the pathogenesis of T2DM.

Should the last be first? Questions and dilemmas regarding early short-term insulin treatment in Type 2 Diabetes Mellitus

INTRODUCTION

Early short-term insulin treatment (STIT), defined as insulin administration shortly after diabetes diagnosis for only a brief period of time, is an alternative concept, aiming to entirely revise the perspective of type 2 diabetes (T2DM) management.

AREAS COVERED

The present review intends to summarize what is already known regarding early STIT in T2DM and highlight questions and dilemmas from the clinician's point of view, with a discourse on future research agenda.

EXPERT OPINION

STIT has the potential to modify the natural history of T2DM, resulting in improved drug-free remission rates by favorably affecting the underlying pathophysiology of the disease. Existing data in the field manifest significant weaknesses, mainly being the small number of trials and patients included, the lack of control groups in most studies and the wide heterogeneity between study designs and explored outcomes, which limit definitive conclusions. Therefore, before such a therapeutic strategy is incorporated into daily practice, important issues require further clarification by future trials. These issues include the optimal time point for the intervention, the ideal insulin type, the identification of patients being most likely to benefit, the STIT effects on cardiovascular and other clinical outcomes and the cost-effectiveness evaluation of this therapeutic strategy.

ABBREVIATIONS

T2DM: Type 2 Diabetes Mellitus; HbA_1C: Hemoglobin A_1c; OHA: Oral Hypoglycemic Agents; STIT: Short-term Insulin Treatment; CSII: Continuous Subcutaneous Insulin Infusion; MDI: Multiple Daily Injections; PPG: Postprandial Plasma Glucose; FPG: Fasting Plasma Glucose; HOMA-b: Homeostasis Model Assessment of beta-cell function; TDD: Total Daily Insulin Dose; DI: Disposition Index; HOMA-IR: Homeostasis Model Assessment of Insulin Resistance; ROS: Reactive Oxygen Species; TNF: Tumor Necrosis Factor; GLP-1: Glucagon-like peptide-1; GIP: Glucose-dependent Insulinotropic Polypeptide; BMI: Body Mass Index; CV: Cardiovascular; DR: Diabetic Retinopathy; SU: Sulfonylurea; IGI: Insulinogenic Index.

Switching from biosimilar (Basalin) to originator (Lantus) insulin glargine is effective in Chinese patients with diabetes mellitus: a retrospective chart review

Background: This study investigated the effectiveness and safety of switching from Basalin® to Lantus® in Chinese patients with diabetes mellitus (DM). Methods:  A retrospective chart review conducted using the electronic medical records of patients hospitalized at the Qingdao Endocrine and Diabetes Hospital from 2005 to 2016. All patients were diagnosed with DM and underwent switching of insulin from Basalin to Lantus during hospitalization. Data collected included fasting (FBG), pre- and post-prandial whole blood glucose, insulin dose, reasons for insulin switching and hypoglycemia. Four study time points were defined as: hospital admission, Basalin initiation, insulin switching (date of final dose of Basalin), and hospital discharge. Blood glucose measurements were imputed as the values recorded closest to the dates of these four time points for each patient. Results: Data from 73 patients (70 patients with type 2 diabetes, 2 with type 1, and 1 undisclosed) were analyzed. At admission, mean glycated hemoglobin (HbA1c) and FBG were 8.9% (SD=1.75) and 9.98 (3.22) mmol/L, respectively. Between Basalin initiation and insulin switch, mean FBG decreased from 9.68 mmol/L to 8.03 mmol/L (p<0.0001), over a mean 10.8 (SD=6.85) days of Basalin treatment, and reduced further to 7.30 mmol/L at discharge (p=0.0116) following a mean 6.6 (7.36) days of Lantus. The final doses of Basalin and Lantus were similar (0.23 vs. 0.24 IU/kg/day; p=0.2409). Furthermore, reductions in pre- and post-prandial blood glucose were also observed between Basalin initiation, insulin switch and hospital discharge. The incidence of confirmed hypoglycemia was low during Basalin (2 [2.4%]) and Lantus (1 [1.2%]) treatment, with no cases of severe hypoglycemia. Conclusion: In this study population, switching from Basalin to Lantus was associated with further reductions in blood glucose, although the dose of insulin glargine did not increase. Further studies are required to verify these findings and determine the reason for this phenomenon.

Short-term intensive insulin therapy could be the preferred option for new onset Type 2 diabetes mellitus patients with HbA1c > 9

Type 2 diabetes mellitus (T2DM) is a heterogeneous disease. Currently, the typical clinical therapeutic pathway for the disease consists of the stepwise addition of antihyperglycemic preparations over time, followed lastly by insulin therapy when functional β-cell capacity is severely deteriorated. Recognizing the complexity of disease management, personalized (precision) medicine approaches may enable the physician to tailor diabetes treatment based on HbA1c levels, body mass index (BMI), efficacy, risk of hypoglycemia, risk of weight gain, age, safety, cost, and even genetic characteristics. Although insulin therapy has traditionally been recommended as the last option in the sequential treatment algorithm of T2DM, it is notable that several guidelines and consensus statements suggest consideration of insulin as part of a first-line regimen. In the American Association of Clinical Endocrinologists (AACE)/American College of Endocrinology (ACE) comprehensive T2DM 2017 management algorithm, insulin is recommended for T2DM patients presenting with symptoms and an HbA1c >9.0%. In addition, the American Diabetes Association (ADA)/European Association for the Study of Diabetes (EASD) consensus statement recommends initial insulin therapy as an option when HbA1c ≥9%, and definite consideration with HbA1c ≥10-12%, and mentions that it may be possible to taper off insulin once initial glucotoxicity is reversed and to consider transfer to other types of non-insulin therapies. Based on accumulating evidence, an expert group has endorsed the concept of short-term intensive insulin (STII) therapy as an option for some patients with T2DM at the time of diagnosis. Notably, the latest Israeli guidelines suggest considering immediate, sometimes short-term, insulin treatment for patients with HbA1c >9% or with symptoms. It has been reported that nearly one-quarter (23%) of newly diagnosed T2DM patients in the US had an HbA1c ≥9.0% prior to initiation of treatment. For such patients, initiating insulin is difficult, although it has been almost 10 years since the ACE/AACE Diabetes Road Map suggested insulin therapy for treatment-naïve patients with high HbA1c. Lack of patient education resources in primary care and of provider knowledge as to approaches to insulin treatment (insulin initiation dosage, multiple daily injection or basal insulin supplement, insulin treatment duration) are major obstacles to selecting appropriately intensive but also timely therapy for newly diagnosed T2DM patients in clinical practice so as to minimize avoidable glycemic exposure. Treatment with STII early in the course of T2DM is of considerable interest. There is a wide range of evidence currently available supporting the use of STII therapy in newly diagnosed T2DM. For example, STII can quickly normalize glycemic control, improve β-cell function, restore first-phase insulin secretion, and even reduce glucagonemia in newly diagnosed T2DM, suggesting that it may provide unique capacity for modification of the natural process of diabetes. The largest and most robust clinical trial of STII therapy enrolled 382 newly diagnosed people with T2DM at nine centers in China and randomized them to either insulin (short-term continuous subcutaneous insulin infusion [CSII] or multiple daily injections [MDI]) or oral anti-hyperglycemic therapy. First-phase insulin secretion was increased in all three groups after 2 weeks of normoglycemia. Remission rates at 1 year were higher in the two insulin-treated groups (51.1% in the CSII group, 44.9% in the MDI group) than in the oral therapy group (26.7%). Furthermore, the increase in first-phase insulin response was maintained at 1 year in the two insulin-treated groups, but declined in the group allocated to oral medication (Fig. ). A beneficial effect of insulin therapy over oral anti-diabetic agents was also observed by Chen et al. [Figure: see text] A meta-analysis, including seven studies and 839 participants, further underscored the robustness of the evidence supporting STII therapy by showing that the proportion of patients in drug-free remission was 66.2% at 3 months, 58.9% at 6 months, 46.3% at 12 months, and 42.1% at 24 months. All but one study showed an improvement in β-cell function, as assessed by homeostatic model assessment of β-cell function (HOMA-B), and all but one study showed a decrease in insulin resistance, as assessed by homeostasis model assessment of insulin resistance (HOMA-IR). Therefore, STII has beneficial effects on both the fundamental pathophysiological mechanisms of T2DM (β-cell dysfunction and insulin resistance). Recent animal studies suggest a potential mechanism for such clinical benefits: β-cells dedifferentiate to endocrine progenitor-like cells during stress-induced hyperglycemia, and strictly normalizing blood glucose by insulin therapy could induce dedifferentiated cell redifferentiation to mature β-cells, and hence restoration of drug responsivity. In addition to its glucose-lowering activity, insulin may contribute to improved β-cell function by its antilipolytic, anti-inflammatory, and antiapoptotic effects. We recognized that not all newly diagnosed people with T2DM would experience improved β-cell function or achieve long-term remission following cessation of STII. It would be worthwhile to precisely identify the subpopulation more likely to benefit from this strategy. Previous studies have suggested that lower baseline fasting glucose, higher BMI, better early phase insulin secretion, and lower exogenous insulin requirements may be predictors of diabetes remission in newly diagnosed patients treated with STII therapy. A recent study demonstrated that a shorter duration of diabetes supplanted baseline HbA1c and β-cell function as an independent predictor of remission. In particular, diabetes duration <2 years predicted sustained remission, suggesting that the key determinant of inducing persistent drug-free diabetes remission with STII is early intervention. Although reluctance to initiate insulin treatment in T2DM is well described, it is interesting to see that when introduced early in the course of the disease as a short-term treatment, STII resulted in significant improvement in patient-reported quality of life and treatment satisfaction, demonstrating the patient acceptability of early insulin therapy. In our clinical experience, patients often request insulin resumption after a trial has ended because of the good clinical outcomes and the recognition that such treatment is much easier and better tolerated than expected. The pros and cons of STII therapy for new-onset T2DM patients with HbA1c >9%, based on current evidence and our understanding, are listed in Table . It is important that STII be considered an option at this early stage of the disease. Existing studies and clinical experience do indicate that this concept is very well received by patients and clinicians alike, especially when they realize that insulin only needs to be used for a few weeks, and that STII at that point in time does not necessarily require continuing long-term insulin therapy. Numerous public health, clinical efficacy and effectiveness, and cost-effectiveness questions need to be better understood before widespread adoption of this novel treatment regimen can be more endorsed. [Table: see text].

Common variants of HNF1A gene are associated with diabetic retinopathy and poor glycemic control in normal-weight Japanese subjects with type 2 diabetes mellitus

AIM

This study investigated the associations between the common hepatocyte nuclear factor-1A (HNF1A) variants and the risk of diabetic retinopathy (DR) in relation to the glycemic control and weight status.

METHODS

A retrospective longitudinal analysis was conducted among 354 Japanese patients with type 2 diabetes mellitus (T2DM) (mean follow-up duration: 5.8±2.5 years). The multivariable-adjusted hazard ratio (HR) for the cumulative incidence of DR was calculated using a Cox proportional hazard model. During the observation period, the longitudinal associations of the HNF1A diplotypes with the risk of DR and the clinical parameters were also analyzed using the generalized estimating equations approach.

RESULTS

The combination of risk variants, i.e., rs1169288-C, rs1183910-A and rs2464196-A, was defined as the H1 haplotype. The incidence of DR was higher in the H1/H1 diplotype cases than in the others (HR 2.75 vs. non-H1/non-H1; p=0.02). Only in normal-weight subjects, the risks of DR and poor glycemic control were higher in the H1/H1 diplotype cases than in the others [odds ratio 4.08 vs. non-H1/non-H1, p=0.02; odds ratio 3.03, p=0.01; respectively].

CONCLUSIONS

This study demonstrated that the common HNF1A diplotype of three risk variants may be an independent risk factor for the development of DR resulting from poor glycemic control in normal-weight patients with T2DM. These results need to be replicated in larger and more varied study populations.

Short-term intensive insulin therapy at diagnosis in type 2 diabetes: plan for filling the gaps

Short-term intensive insulin therapy is unique amongst therapies for type 2 diabetes because it offers the potential to preserve and improve beta-cell function without additional pharmacological treatment. On the basis of clinical experience and the promising results of a series of studies in newly diagnosed patients, mostly in Asian populations, an expert workshop was convened to assess the available evidence and the potential application of short-term intensive insulin therapy should it be advocated for inclusion in clinical practice. Participants included primary care physicians and endocrinologists. We endorse the concept of short-term intensive insulin therapy as an option for some patients with type 2 diabetes at the time of diagnosis and have identified the following six areas where additional knowledge could help clarify optimal use in clinical practice: (1) generalizability to primary care, (2) target population and biomarkers, (3) follow-up treatment, (4) education of patients and providers, (5) relevance of ethnicity, and (6) health economics.

Early therapy for type 2 diabetes in China

Diabetes is a huge burden in China, where about 100 million people have been diagnosed with the disease. Treatments are needed that are optimal for treating Chinese patients with diabetes. Chinese patients with type 2 diabetes are characterised by having relatively low bodyweight and significant β-cell deterioration. β-cell failure results in deficiency of insulin secretion, particularly at the early phase of insulin secretion in Chinese patients. As a result, postprandial hyperglycaemia is more pronounced in Chinese patients with early type 2 diabetes than most other ethnic groups. These characteristics point to the key strategies when considering early therapy for Chinese patients with type 2 diabetes, including control of postprandial hyperglycaemia and β-cell preservation. Besides metformin, insulin secretagogues and α-glucosidase inhibitors that target postprandial hyperglycaemia are recommended for drug-naive patients. Short-term intensive insulin therapy is suggested for patients with severe hyperglycaemia at diagnosis to help restore β-cell function. Use of incretin-based drugs is also recommended when treatment fails with metformin, insulin secretagogues, and α-glucosidase inhibitors. Although data on antidiabetic drugs in Chinese patients are growing, there are still gaps in the evidence base. Research is needed to strengthen the evidence-based treatment guidelines for Chinese patients with type 2 diabetes.

[Timely commencement of insulin in type 2 diabetes: benefits and risks]

The introduction of insulin in type 2 diabetes is often too late, though the immediate as well as late consequences of inadequate metabolic control are well known. That is the reason, why a special attention is given in recent therapeutic guidelines for the importance of early, at least timely insulinisation. This review article summarizes the advantages (mitigation of the beta-cell dysfunction, long lasting good metabolic control) and potential risks (hypoglycemia, weight gain, possible deteriorating patient compliance) of early or timely insulin therapy. It is pointed out that the introduction of insulin is effective and safe therapeutic option during the whole course of type 2 diabetes, the use of different regimes is suitable to reach and maintain the individual glycemic target and, with a structured patient education, it does not disturb the quality of life and the compliance of patients.