Pioglitazone as adjunctive therapy in adolescents with type 1 diabetes

Use of adjunctive glycaemic agents with vascular protective properties in individuals with type 1 diabetes: Potential benefits and risks

Glycaemic therapy in type 1 diabetes (T1D) is focused on insulin, with the majority of studies investigating different insulin preparations, delivery devices and dosing accuracy methods. While insulin deficiency is the key mechanism for hyperglycaemia in T1D, individuals with this condition can also develop insulin resistance (IR), making optimisation of glycaemia more challenging. Importantly, IR in T1D increases the risk of both microvascular and macrovascular complications; yet, it is rarely targeted in routine clinical care. In this narrative review, we briefly discuss the mechanistic pathways for diabetes complications in individuals with T1D, emphasising the adverse role of IR. We subsequently cover the use of adjunctive glycaemic therapies for improving the metabolic profile in T1D, focusing on therapies that have possible or definite cardiovascular or renal protective properties in individuals with type 2 diabetes. These include metformin and agents in the thiazolidinedione, Sodium-Glucose Cotransporter-2 inhibitor (SGLT2i) and Glucagon-Like Peptide-1 Receptor Agonists (GLP-1RA) groups. In addition to reviewing the role of these agents in improving metabolic parameters, we address their potential vascular and renal protective effects in individuals with T1D. We suggest a pragmatic approach for using these agents in T1D, based on current knowledge of their benefits and risks, while also highlighting gaps in knowledge and areas that require further research. It is hoped that the review raises awareness of the role of adjunctive therapies in T1D and offers healthcare professionals simple guidance on using such agents for the management of high-risk individuals with T1D.

The combined pioglitazone and topiramate therapy for management of pediatric patients with severe MASLD

BACKGROUND

Metabolic dysfunction associated steatotic liver disease (MASLD) is the most common cause of chronic hepatitis in adult and pediatric patients. Adolescents with severe MASLD can demonstrate a more aggressive disease phenotype as they more commonly develop liver fibrosis than BMI matched adults. Therefore, MASLD is the fastest growing indication for liver transplants in young adults.

METHODS

Pioglitazone has been shown to improve liver histology in adult patients with MASLD, and in some studies, it attenuated liver fibrosis. Despite its perceived efficacy, pioglitazone is not widely used, likely due to its side effect profile, specifically increased weight gain. Topiramate lowers body weight in adolescents and in combination with phentermine, is one of the few FDA-approved medications for the management of obesity in children over 12 years of age. We performed a retrospective review of the outcomes in pediatric patients with severe MASLD, treated with the combined pioglitazone and topiramate therapy.

RESULTS

Here, we report a case series of seven adolescents with severe MASLD and ≥F2 liver fibrosis treated with the combined pioglitazone and topiramate therapy. The combined therapy improved mean serum ALT from 165 ± 80 U/L to 89 ± 62 U/L after 12 months mean duration of treatment. One patient who completed 24 months of the combined therapy demonstrated a decrease in liver stiffness from 8.9 kPa to 5.6 kPa, as assessed by FibroScan elastography. There was a significant increase in body weight during this time, however, body mass index as a percentage of the 95 th percentile adjusted for age and gender did not increase significantly, 151 ± 29% vs. 152 ± 28%. Moreover, waist circumference, mid-upper arm circumference, percent body fat, and muscle mass were not significantly different before and after treatment. Serum lipid levels and hemoglobin A1c also did not change with the treatment.

CONCLUSION

In summary, this case series provides encouraging results about the efficacy of the combined pioglitazone and topiramate therapy for the management of adolescents with severe MASLD, which should be further explored in clinical studies.

Glucose-Lowering Therapy beyond Insulin in Type 1 Diabetes: A Narrative Review on Existing Evidence from Randomized Controlled Trials and Clinical Perspective

Background: In Type 1 diabetes (T1D), according to the most recent guidelines, the everyday glucose-lowering treatment is still restricted to the use of subcutaneous insulin, while multiple therapeutic options exist for Type 2 diabetes (T2D). Methods: For this narrative review we unsystematically screened PubMed and Embase to identify clinical trials which investigated glucose-lowering agents as an adjunct to insulin treatment in people with T1D. Published studies up to March 2022 were included. We discuss the safety and efficacy in modifying cardiovascular risk factors for each drug, the current status of research, and provide a clinical perspective. Results: For several adjunct agents, in T1D, the scientific evidence demonstrates improvements in HbA1c, reductions in the risk of hypoglycemia, and achievements of lower insulin requirements, as well as positive effects on cardiovascular risk factors, such as blood lipids, blood pressure, and weight. As the prevalence of obesity, the major driver for double diabetes, is rising, weight and cardiovascular risk factor management is becoming increasingly important in people with T1D. Conclusions: Adjunct glucose-lowering agents, intended to be used in T2D, bear the potential to beneficially impact on cardiovascular risk factors when investigated in the T1D population and are suggested to be more extensively considered as potentially disease-modifying drugs in the future and should be investigated for hard cardiovascular endpoints.

Double Diabetes: A Growing Problem Requiring Solutions

The growing proportion of type 1 diabetes mellitus (T1DM) patients with clinical features of insulin resistance (IR) has led to the description of a distinctive T1DM subgroup, still unrecognised by current guidelines, called double diabetes, assumingly associated with poorer metabolic phenotype and increased risk of micro- and macrovascular complications. The main goal of identifying double diabetes, estimated to be present in up to half of T1DM patients, is timely implementation of appropriate therapeutic interventions to reduce the increased risk of chronic complications and other adverse metabolic traits associated with this condition. Proposed diagnostic criteria are largely divided into three different groups: family history of type 2 diabetes mellitus (T2DM), obesity/metabolic syndrome, and IR. Estimated glucose disposal rate may prove the most reliable marker of double diabetes. In addition to general measures (diet, physical activity, antihypertensive, and lipid-lowering medications, etc.) and development of new insulin preparations with more hepatic action, double diabetes patients may derive more benefit from agents developed for T2DM. Indeed, such potentially promising agents include glucagon-like peptide-1 receptor agonists, sodium-glucose contrasporter-2 inhibitors, and their combination. We are now awaiting long-term trials assessing metabolic and vascular benefits of these medications in double diabetes.

Mitochondrial dynamics in the neonatal brain - a potential target following injury?

The impact of birth asphyxia and its sequelae, hypoxic–ischaemic (HI) brain injury, is long-lasting and significant, both for the infant and for their family. Treatment options are limited to therapeutic hypothermia, which is not universally successful and is unavailable in low resource settings. The energy deficits that accompany neuronal death following interruption of blood flow to the brain implicate mitochondrial dysfunction. Such HI insults trigger mitochondrial outer membrane permeabilisation leading to release of pro-apoptotic proteins into the cytosol and cell death. More recently, key players in mitochondrial fission and fusion have been identified as targets following HI brain injury. This review aims to provide an introduction to the molecular players and pathways driving mitochondrial dynamics, the regulation of these pathways and how they are altered following HI insult. Finally, we review progress on repurposing or repositioning drugs already approved for other indications, which may target mitochondrial dynamics and provide promising avenues for intervention following brain injury. Such repurposing may provide a mechanism to fast-track, low-cost treatment options to the clinic.

Treating latent autoimmune diabetes in adults in the era of cardiovascular outcomes trials: Old dog should learn new tricks

BACKGROUND

Latent autoimmune diabetes in adults (LADA) is characterised by pathophysiological and clinical heterogeneity. Hence, the optimal treatment strategy for this type of diabetes remains a clinical challenge.

AIM

To discuss the potential of a modern therapeutic approach for LADA in the context of the novel findings of cardiovascular outcomes trials and stress the controversies surrounding LADA and the barriers in the effective management of people with this type of diabetes.

METHODS

We performed a literature search in major biomedical databases in order to retrieve relevant literature. The results of key studies, along with the authors' clinical experience and perspective, are summarised and discussed in this narrative, mini review article.

RESULTS

Insulin remains the primary treatment choice in individuals with low C-peptide levels. Although cardiovascular outcomes trials have mainly recruited participants with type 2 diabetes, recent data suggest that the cardiorenal protective properties of the new therapies are even present in people without diabetes and thus, the extrapolation of their results on LADA individuals sounds reasonable. Therefore, sodium-glucose co-transporter 2 inhibitors (SGLT2is) and glucagon-like peptide-1 receptor agonists should be considered for the management of people with preserved insulin production being at high cardiovascular risk. The risk of diabetic ketoacidosis with SGLT2is requires increased vigilance by treating physicians.

CONCLUSIONS

Individualisation, preservation of beta-cell mass and function and cardiorenal protection are the new challenges in LADA therapy.

Age, sex, disease severity, and disease duration difference in placebo response: implications from a meta-analysis of diabetes mellitus

BACKGROUND

The placebo response in patients with diabetes mellitus is very common. A systematic evaluation needs to be updated with the current evidence about the placebo response in diabetes mellitus and the associated factors in clinical trials of anti-diabetic medicine.

METHODS

Literature research was conducted in Medline, Embase, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov for studies published between the date of inception and June 2019. Randomized placebo-controlled trials conducted in type 1and type 2 diabetes mellitus (T1DM/T2DM) were included. Random-effects model and meta-regression analysis were accordingly used. This meta-analysis was registered in PROSPERO as CRD42014009373.

RESULTS

Significantly weight elevation (effect size (ES) = 0.33 kg, 95% CI, 0.03 to 0.61 kg) was observed in patients with placebo treatments in T1DM subgroup while significantly HbA1c reduction (ES = - 0.12%, 95% CI, - 0.16 to - 0.07%) and weight reduction (ES = - 0.40 kg, 95% CI, - 0.50 to - 0.29 kg) were observed in patients with placebo treatments in T2DM subgroup. Greater HbA1c reduction was observed in patients with injectable placebo treatments (ES = - 0.22%, 95% CI, - 0.32 to - 0.11%) versus oral types (ES = - 0.09%, 95% CI, - 0.14 to - 0.04%) in T2DM (P = 0.03). Older age (β = - 0.01, 95% CI, - 0.02 to - 0.01, P < 0.01) and longer diabetes duration (β = - 0.02, 95% CI, - 0.03 to - 0.21 × 10^-2, P = 0.03) was significantly associated with more HbA1c reduction by placebo in T1DM. However, younger age (β = 0.02, 95% CI, 0.01 to 0.03, P = 0.01), lower male percentage (β = 0.01, 95% CI, 0.22 × 10^-2, 0.01, P < 0.01), higher baseline BMI (β = - 0.02, 95% CI, - 0.04 to - 0.26 × 10^-2, P = 0.02), and higher baseline HbA1c (β = - 0.09, 95% CI, - 0.16 to - 0.01, P = 0.02) were significantly associated with more HbA1c reduction by placebo in T2DM. Shorter diabetes duration (β = 0.06, 95% CI, 0.06 to 0.10, P < 0.01) was significantly associated with more weight reduction by placebo in T2DM. However, the associations between baseline BMI, baseline HbA1c, and placebo response were insignificant after the adjusted analyses.

CONCLUSION

The placebo response in diabetes mellitus was systematically outlined. Age, sex, disease severity (indirectly reflected by baseline BMI and baseline HbA1c), and disease duration were associated with placebo response in diabetes mellitus. The association between baseline BMI, baseline HbA1c, and placebo response may be the result of regression to the mean.

PPARγ and Cognitive Performance

Recent findings have led to the discovery of many signaling pathways that link nuclear receptors with human conditions, including mental decline and neurodegenerative diseases. PPARγ agonists have been indicated as neuroprotective agents, supporting synaptic plasticity and neurite outgrowth. For these reasons, many PPARγ ligands have been proposed for the improvement of cognitive performance in different pathological conditions. In this review, the research on this issue is extensively discussed.

PPARγ agonists: potential treatment for autism spectrum disorder by inhibiting the canonical WNT/β-catenin pathway

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is characterized by a deficit in social interactions and communication with repetitive and restrictive behavior. No curative treatments are available for ASD. Pharmacological treatments do not address the core ASD behaviors, but target comorbid symptoms. Dysregulation of the core neurodevelopmental pathways is associated with the clinical presentation of ASD, and the canonical WNT/β-catenin pathway is one of the major pathways involved. The canonical WNT/β-catenin pathway participates in the development of the central nervous system, and its dysregulation involves developmental cognitive disorders. In numerous tissues, the canonical WNT/β-catenin pathway and peroxisome proliferator-activated receptor gamma (PPARγ) act in an opposed manner. In ASD, the canonical WNT/β-catenin pathway is increased while PPARγ seems to be decreased. PPARγ agonists present a beneficial effect in treatment for ASD children through their anti-inflammatory role. Moreover, they induce the inhibition of the canonical WNT/β-catenin pathway in several pathophysiological states. We focus this review on the hypothesis of an opposed interplay between PPARγ and the canonical WNT/β-catenin pathway in ASD and the potential role of PPARγ agonists as treatment for ASD.

Nuclear Peroxisome Proliferator-Activated Receptors (PPARs) as Therapeutic Targets of Resveratrol for Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by defective social communication and interaction and restricted, repetitive behavior with a complex, multifactorial etiology. Despite an increasing worldwide prevalence of ASD, there is currently no pharmacological cure to treat core symptoms of ASD. Clinical evidence and molecular data support the role of impaired mitochondrial fatty acid oxidation (FAO) in ASD. The recognition of defects in energy metabolism in ASD may be important for better understanding ASD and developing therapeutic intervention. The nuclear peroxisome proliferator-activated receptors (PPAR) α, δ, and γ are ligand-activated receptors with distinct physiological functions in regulating lipid and glucose metabolism, as well as inflammatory response. PPAR activation allows a coordinated up-regulation of numerous FAO enzymes, resulting in significant PPAR-driven increases in mitochondrial FAO flux. Resveratrol (RSV) is a polyphenolic compound which exhibits metabolic, antioxidant, and anti-inflammatory properties, pointing to possible applications in ASD therapeutics. In this study, we review the evidence for the existing links between ASD and impaired mitochondrial FAO and review the potential implications for regulation of mitochondrial FAO in ASD by PPAR activators, including RSV.

Pharmacologic adjunctive to insulin therapies in type 1 diabetes: The journey has just begun

Treatment of type 1 diabetes (T1D) is currently based exclusively on insulin replacement therapy. However, there is a need for better glycemic control, lower hypoglycemia rates, more effective weight management, and further reduction of cardiovascular risk in people with T1D. In this context, agents from the pharmaceutical quiver of type 2 diabetes are being tested in clinical trials, as adjunctive to insulin therapies for T1D patients. Despite the limited amount of relevant evidence and the inter-class variability, it can be said that these agents have a role in optimizing metabolic control, assisting weight management and reducing glycemic variability in people with T1D. Specific safety issues, including the increased risk of hypoglycemia and diabetic ketoacidosis, as well as the effects of these treatments on major cardiovascular outcomes should be further assessed by future studies, before these therapeutic choices become widely available for T1D management.

A pilot dose finding study of pioglitazone in autistic children

Background

Pioglitazone is a promising compound for treatment of core autism spectrum disorder (ASD) symptoms as it targets multiple relevant pathways, including immune system alterations.

Objective

This pilot study aimed to elucidate the maximum tolerated dose, safety, preliminary evidence of efficacy, and appropriate outcome measures in autistic children ages 5–12 years old.

Methods

We conducted a 16-week prospective cohort, single blind, single arm, 2-week placebo run-in, dose-finding study of pioglitazone. Twenty-five participants completed treatment. A modified dose finding method was used to determine safety and dose response among three dose levels: 0.25 mg/kg, 0.5 mg/kg, and 0.75 mg/kg once daily.

Results

Maximum tolerated dose: there were no serious adverse events (SAEs) and as such the maximum tolerated dose within the range tested was 0.75 mg/Kg once daily.

Safety: overall, pioglitazone was well tolerated. Two participants discontinued intervention due to perceived non-efficacy and one due to the inability to tolerate interim blood work. Three participants experienced mild neutropenia.

Early evidence of efficacy: statistically significant improvement was observed in social withdrawal, repetitive behaviors, and externalizing behaviors as measured by the Aberrant Behavior Checklist (ABC), Child Yale-Brown Obsessive Compulsive Scale (CY-BOCS), and Repetitive Behavior Scale–Revised (RBS-R). Forty-six percent of those enrolled were deemed to be global responders.

Conclusions and relevance

Pioglitazone is well-tolerated and shows a potential signal in measures of social withdrawal, repetitive, and externalizing behaviors. Randomized controlled trials using the confirmed dose are warranted.

Trial registration

ClinicalTrials.gov, NCT01205282. Registration date: September 20, 2010. 

Electronic supplementary material

The online version of this article (10.1186/s13229-018-0241-5) contains supplementary material, which is available to authorized users.

Non-insulin pharmacological therapies for treating type 1 diabetes

INTRODUCTION

Despite intensified insulin treatment, many persons with type 1 diabetes (T1D) do not achieve glycemic and metabolic targets. Consequently, non-insulin chemical therapies that improve glycemic control and metabolic parameters without increasing the risk of adverse events (including hypoglycemia) are of interest as adjunct therapies to insulin.

AREAS COVERED

In this review, the authors discuss the efficacy and safety of non-insulin therapies, including pramlintide, glucagon-like peptide-1 (GLP-1) receptor agonists, dipeptidyl peptidase-4 inhibitors (DPP-4), sodium-glucose cotransporter (SGLT1 and SGLT2) inhibitors, metformin, sulfonylureas, and thiazolidinediones as add-on therapies to insulin in T1D.

EXPERT OPINION

The current evidence shows that the efficacy of non-insulin therapies as add-on therapies to insulin is minimal or modest with an average HbA1c reduction of 0.2-0.5% (2-6 mmol/mol). Indeed, the current focus is on the development of SGLT inhibitors as adjuncts to insulin in type 1 diabetes. Studies of subgroups with obesity, residual beta-cell function (including newly diagnosed patients) and patients prone to hypoglycemia could be areas of future research.

Adjuvant Pharmacotherapies to Insulin for the Treatment of Type 1 Diabetes

PURPOSE OF REVIEW

Insulin therapy alone fails to achieve target glycemic control in the majority of individuals with type 1 diabetes (T1D), motivating the investigation of additive medications. This review focuses on the recent findings on the use of adjunctive pharmacotherapy in T1D.

RECENT FINDINGS

Metformin and glucagon-like peptide-1 receptor agonists have been associated with weight reduction and decrease in daily insulin requirements without sustainable improvement in glycemic control. Sodium-glucose cotransporter (SGLT)-2 inhibitors, dual SGLT-1/2 inhibitors, and pramlintide have been shown to reduce hemoglobin A1c, induce weight loss, and lower insulin dose. The benefits of dipeptidyl peptidase-4 inhibitors, thiazolidinediones, and alpha glucosidase inhibitors appear to be more limited. Gastrointestinal symptoms and increased hypoglycemia are adverse effects of certain classes. Although not devoid of side effects, additive pharmacotherapies in T1D can improve glycemic control and lower body weight and insulin requirement. Longer studies are needed before consideration for widespread clinical care.

Insulin resistance, role of metformin and other non-insulin therapies in pediatric type 1 diabetes

Type 1 diabetes mellitus (T1DM) in youth is a challenging chronic medical condition. Its management should address not only the glycemic control but also insulin resistance and cardiovascular disease risk factors which are increasingly recognized to be present in youth with TID. Current knowledge on the mechanisms of insulin resistance in T1DM is reviewed. The use of adjunctive therapies that are beneficial to achieve adequate glycemic control while mitigating the effects of insulin resistance are discussed with a focus on metformin therapy and an overview of other new pharmacologic agents.

Peroxisome Proliferator-activated Receptor-γ Activation Augments the β-Cell Unfolded Protein Response and Rescues Early Glycemic Deterioration and β Cell Death in Non-obese Diabetic Mice

Type 1 diabetes is an autoimmune disorder that is characterized by a failure of the unfolded protein response in islet β cells with subsequent endoplasmic reticulum stress and cellular death. Thiazolidinediones are insulin sensitizers that activate the nuclear receptor PPAR-γ and have been shown to partially ameliorate autoimmune type 1 diabetes in humans and non-obese diabetic (NOD) mice. We hypothesized that thiazolidinediones reduce β cell stress and death independently of insulin sensitivity. To test this hypothesis, female NOD mice were administered pioglitazone during the pre-diabetic phase and assessed for insulin sensitivity and β cell function relative to controls. Pioglitazone-treated mice showed identical weight gain, body fat distribution, and insulin sensitivity compared with controls. However, treated mice showed significantly improved glucose tolerance with enhanced serum insulin levels, reduced β cell death, and increased β cell mass. The effect of pioglitazone was independent of actions on T cells, as pancreatic lymph node T cell populations were unaltered and T cell proliferation was unaffected by pioglitazone. Isolated islets of treated mice showed a more robust unfolded protein response, with increases in Bip and ATF4 and reductions in spliced Xbp1 mRNA. The effect of pioglitazone appears to be a direct action on β cells, as islets from mice treated with pioglitazone showed reductions in PPAR-γ (Ser-273) phosphorylation. Our results demonstrate that PPAR-γ activation directly improves β cell function and survival in NOD mice by enhancing the unfolded protein response and suggest that blockade of PPAR-γ (Ser-273) phosphorylation may prevent type 1 diabetes.

Non-insulin drugs to treat hyperglycaemia in type 1 diabetes mellitus

Insulin treatment of individuals with type 1 diabetes has shortcomings and many patients do not achieve glycaemic and metabolic targets. Consequently, the focus is on novel non-insulin therapeutic approaches that reduce hyperglycaemia and improve metabolic variables without increasing the risk of hypoglycaemia or other adverse events. Several therapies given in conjunction with insulin have been investigated in clinical trials, including pramlintide, glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors, sodium-glucose co-transporter inhibitors, metformin, sulfonylureas, and thiazolidinediones. These drugs have pleiotropic effects on glucose metabolism and different actions complementary to those of insulin-this Review reports the effects of these drugs on glycaemic control, glucose variability, hypoglycaemia, insulin requirements, and bodyweight. Existing studies are of short duration with few participants; evidence for the efficacy of concomitant treatments is scarce and largely clinically insignificant. A subgroup of patients with type 1 diabetes for whom non-insulin antidiabetic drugs could significantly benefit glycaemic control cannot yet be defined, but we suggest that obese patients prone to hypoglycaemia and patients with residual β-cell function are populations of interest for future trials.

Management of Severe Insulin Resistance in Patients with Type 1 Diabetes

Managing severe insulin resistance (IR) in patients with type 1 diabetes (T1DM) can be challenging for both clinicians and patients. As average weight for patients with T1DM has increased in recent decades, IR in this population has become more widespread. Currently, almost 50 % of patients with T1DM are overweight or obese. While intensive insulin therapy is associated with reduction in complications, aggressive treatment can lead to weight gain. With increasing weight, insulin can become less effective to control glycemia, resulting in higher insulin doses and hence more weight gain. Novel strategies to break this vicious cycle are needed. This review will investigate current research on insulin formulations, lifestyle modification, adjunct therapies, and surgery that may help better manage patients with T1DM and IR.

Alternative Agents in Type 1 Diabetes in Addition to Insulin Therapy: Metformin, Alpha-Glucosidase Inhibitors, Pioglitazone, GLP-1 Agonists, DPP-IV Inhibitors, and SGLT-2 Inhibitors

Insulin is the mainstay of current treatment for patients with type 1 diabetes mellitus (T1DM). Due to increasing insulin resistance, insulin doses are often continually increased, which may result in weight gain for patients. Medications currently approved for the treatment of type 2 diabetes offer varying mechanisms of action that can help to reduce insulin resistance and prevent or deter weight gain. A MEDLINE search was conducted to review literature evaluating the use of metformin, alpha-glucosidase inhibitors, pioglitazone, glucagon-like peptide 1 agonists, dipeptidyl peptidase, and sodium-dependent glucose transporter 2 inhibitors, in patients with T1DM. Varying results were found with some benefits including reductions in hemoglobin A1c, decreased insulin doses, and favorable effects on weight. Of significance, a common fear of utilizing multiple therapies for diabetes treatment is the risk of hypoglycemia, and this review displayed limited evidence of hypoglycemia with multiple agents.

Type 1 diabetes, metabolic syndrome and cardiovascular risk

Patients with type 1 diabetes mellitus (T1DM) traditionally had a low body mass index and microangiopathic complications were common, while macroangiopathy and the metabolic syndrome were exceptional. The Diabetes Control and Complications Trial, published in 1993, demonstrated that therapy aimed at maintaining HbA1c levels as close to normal as feasible reduced the incidence of microangiopathy. Since then, the use of intensive insulin therapy to optimize metabolic control became generalized. Improved glycemic control resulted in a lower incidence of microangiopathy; however, its side effects included a higher rate of severe hypoglycemia and increased weight gain. Approximately 50% of patients with T1DM are currently obese or overweight, and between 8% and 40% meet the metabolic syndrome criteria. The components of the metabolic syndrome and insulin resistance have been linked to chronic T1DM complications, and cardiovascular disease is now the leading cause of death in these patients. Therefore, new therapeutic strategies are required in T1DM subjects, not only to intensively lower glycemia, but to control all associated metabolic syndrome traits.

Effect of pioglitazone on the course of new-onset type 1 diabetes mellitus

OBJECTIVE

Type 1 diabetes mellitus (T1DM) is caused by insulin deficiency resulting from progressive destruction of β cells. The histological hallmark of the diabetic islet is mononuclear cell infiltration. Thiazolidinediones (TZDs) activate PPARg and enhance the actions of insulin. Studies in non-obese diabetic and streptocotozin-treated mouse models demonstrated that pretreatment with TZDs prevented the development of T1DM. The purpose of this study was to examine whether pioglitazone, given with insulin, preserved β cell function in patients with new-onset T1DM.

METHODS

This was a randomized, double-blind, placebo-controlled 24-week study. Subjects received pioglitazone or placebo. Blood sugar, glycated hemoglobin (HbA1c), C-peptide, and liver enzymes were measured at baseline. Boost© stimulated C-peptide responses were measured at baseline and at 24 weeks. Blood sugar, insulin dose, height, weight, and liver enzymes were monitored at each visit. HbA1c was performed every 12 weeks.

RESULTS

Of the 15 patients, 8 received pioglitazone, and 7 - placebo. There was no clinical improvement in HbA1c between or within groups at the completion of the study. Mean peak C-peptide values were similar between groups at baseline. Mean peak C-peptide level was slightly higher at 24 weeks in the pioglitazone group compared to the placebo (1.8 vs. 1.5 ng/mL) which was considered as clinically insignificant. The interaction of HbA1c and insulin dose (HbA1c* insulin/kg/day), which combines degree of diabetic control and dose of insulin required to achieve this control, showed transient improvement in the pioglitazone group at 12 weeks but was not sustained at 24 weeks.

CONCLUSION

In this pilot study, pioglitazone did not preserve β cell function when compared to placebo.

Thiazolidinedione safety

INTRODUCTION

Thiazolidinediones (TZDs) initially showed great promise as unique receptor-mediated oral therapy for type 2 diabetes, but a host of serious side effects, primarily cardiovascular, have limited their utility. It is crucial at this point to perform a risk-benefit analysis to determine what role TZDs should play in our current treatment of type 2 diabetes and where the future of this class of drugs is headed.

AREAS COVERED

This review provides a comprehensive overview of the literature from 2000 onward reporting the known side effects of rosiglitazone and pioglitazone, with commentary on the quality of the data available, putative mechanism of each side effect and clinical significance. Finally, a perspective on the future of the TZDs as a class is provided.

EXPERT OPINION

The current TZDs are first-generation, non-specific activators of peroxisome proliferator-activated receptor (PPAR) gamma, resulting in a wide array of deleterious side effects that currently limit their use. However, the development of highly targeted selective PPAR gamma modulators (SPPARγMs) and dual PPAR gamma/alpha agonists is on the horizon.

Cardiovascular risk in double diabetes mellitus--when two worlds collide

Historically, clinical management of patients with type 1 diabetes mellitus (T1DM) has been focused on glycaemic control, which is sometimes achieved at the expense of weight gain on intensive insulin regimes. Although HbA(1c) level is an important contributor to increased macrovascular risk, several prospective studies have concluded that factors related to obesity, metabolic syndrome and insulin resistance are more important than HbA(1c) for the prediction of cardiovascular risk, especially for coronary heart disease events. 'Double diabetes mellitus' describes a combination of T1DM with characteristics associated with type 2 diabetes mellitus, including central adiposity and exacerbation of insulin resistance. In lean patients with T1DM, portal insulinopaenia might actually confer cardioprotective effects via changes in hepatic lipid profiles (mainly increased HDL cholesterol levels) and a reduction in hepatic steatosis. In patients with double diabetes mellitus, this situation is reversed and atherothrombotic pathophysiology is potentially accelerated by the combination of chronic hyperglycaemia and abnormal lipid partitioning. The prevalence of double diabetes mellitus is increasing in parallel with the societal trend of increased adiposity. This Review discusses how to identify patients susceptible to double diabetes mellitus and suggests alterations to their clinical management that might reduce their risk of future premature coronary disease.

Childhood obesity and environmental chemicals

Childhood and adolescent rates of obesity and overweight are continuing to increase in much of the world. Risk factors such as diet composition, excess caloric intake, decreased exercise, genetics, and the built environment are active areas of etiologic research. The obesogen hypothesis, which postulates that prenatal and perinatal chemical exposure can contribute to risk of childhood and adolescent obesity, remains relatively underexamined. This review surveys numerous classes of chemicals for which this hypothesis has been explored. We focus on human data where they exist and also discuss the findings of rodent and cell culture studies. Organochlorine chemicals as well as several classes of chemicals that are peroxisome proliferator-activated receptor agonists are identified as possible risk factors for obesity. Recommendations for future epidemiologic and experimental research on the chemical origins of obesity are also given.

Type 1 Diabetes: Etiology, Immunology, and Therapeutic Strategies

Type 1 diabetes (T1D) is a chronic autoimmune disease in which destruction or damaging of the beta-cells in the islets of Langerhans results in insulin deficiency and hyperglycemia. We only know for sure that autoimmunity is the predominant effector mechanism of T1D, but may not be its primary cause. T1D precipitates in genetically susceptible individuals, very likely as a result of an environmental trigger. Current genetic data point towards the following genes as susceptibility genes: HLA, insulin, PTPN22, IL2Ra, and CTLA4. Epidemiological and other studies suggest a triggering role for enteroviruses, while other microorganisms might provide protection. Efficacious prevention of T1D will require detection of the earliest events in the process. So far, autoantibodies are most widely used as serum biomarker, but T-cell readouts and metabolome studies might strengthen and bring forward diagnosis. Current preventive clinical trials mostly focus on environmental triggers. Therapeutic trials test the efficacy of antigen-specific and antigen-nonspecific immune interventions, but also include restoration of the affected beta-cell mass by islet transplantation, neogenesis and regeneration, and combinations thereof. In this comprehensive review, we explain the genetic, environmental, and immunological data underlying the prevention and intervention strategies to constrain T1D.

A systematic review of the reporting of Data Monitoring Committees' roles, interim analysis and early termination in pediatric clinical trials

BACKGROUND

Decisions about interim analysis and early stopping of clinical trials, as based on recommendations of Data Monitoring Committees (DMCs), have far reaching consequences for the scientific validity and clinical impact of a trial. Our aim was to evaluate the frequency and quality of the reporting on DMC composition and roles, interim analysis and early termination in pediatric trials.

METHODS

We conducted a systematic review of randomized controlled clinical trials published from 2005 to 2007 in a sample of four general and four pediatric journals. We used full-text databases to identify trials which reported on DMCs, interim analysis or early termination, and included children or adolescents. Information was extracted on general trial characteristics, risk of bias, and a set of parameters regarding DMC composition and roles, interim analysis and early termination.

RESULTS

110 of the 648 pediatric trials in this sample (17%) reported on DMC or interim analysis or early stopping, and were included; 68 from general and 42 from pediatric journals. The presence of DMCs was reported in 89 of the 110 included trials (81%); 62 papers, including 46 of the 89 that reported on DMCs (52%), also presented information about interim analysis. No paper adequately reported all DMC parameters, and nine (15%) reported all interim analysis details. Of 32 trials which terminated early, 22 (69%) did not report predefined stopping guidelines and 15 (47%) did not provide information on statistical monitoring methods.

CONCLUSIONS

Reporting on DMC composition and roles, on interim analysis results and on early termination of pediatric trials is incomplete and heterogeneous. We propose a minimal set of reporting parameters that will allow the reader to assess the validity of trial results.

[Adjunctive therapies to glycaemic control of type 1 diabetes mellitus]

Since Diabetes Control and Complications Trial (DCCT), intensive therapy has been directed at achieving glucose and glycosylated hemoglobin (HbA1c) values as close to normal as possible regarding safety issues. However, hyperglycemia (especially postprandial hyperglycemia) and hypoglicemia continue to be problematic in the management of type 1 diabetes. The objective of associating other drugs to insulin therapy is to achieve better metabolic control lowering postprandial blood glucose levels. Adjunctive therapies can be divided in four categories based on their mechanism of action: enhancement of insulin action (e.g. the biguanides and thiazolidinediones), alteration of gastrointestinal nutrient delivery (e.g. acarbose and amylin) and other targets of action (e.g. pirenzepine, insulin-like growth factor I and glucagon-like peptide-1). Many of these agents have been found to be effective in short-term studies with decreases in HbA1c of 0.5-1%, lowering postprandial blood glucose levels and decreasing daily insulin doses.

Pioglitazone and cardiovascular risk. A comprehensive meta-analysis of randomized clinical trials

AIM

The aim of this meta-analysis of randomized clinical trials (RCT) was to assess whether pioglitazone is also associated with increased cardiovascular risk, as recently reported for rosiglitazone.

METHODS

RCT of pioglitazone were retrieved from Medline (any date up to 31 August 2007; English language only). Unpublished RCT were identified through http://www.clinicaltrials.gov or http://www.fda.gov websites, and results on cardiovascular outcomes were retrieved from investigators and/or sponsors, whenever possible. RCT were included in meta-analysis if pioglitazone was compared with other treatments (placebo, active comparators or no treatment) for at least 4 weeks. Ninety-four trials, 10 of which were unpublished, were retrieved; those included in the analysis, which excluded PROspective PioglitAzone Clinical Trial In MacroVascular Events (PROACTIVE), enrolled 11 268 and 9912 patients in the pioglitazone and comparator groups respectively. Data for analysis, extracted independently by two observers, included all-cause and cardiovascular mortality and incidence of non-fatal coronary events and heart failure. Proportions of outcome measures across treatment groups were compared by odds ratios (ORs) and 95% confidence interval.

RESULTS

Pioglitazone was associated with reduced all-cause mortality [OR 0.30 (0.14-0.63); p < 0.05], with no relevant effect on non-fatal coronary events. The observed increase in incidence of non-fatal heart failure was not statistically significant [OR 1.38 (0.90-2.12)].

CONCLUSION

The use of pioglitazone does not appear to be harmful in terms of cardiovascular events and all-cause deaths.

Addressing insulin resistance in Type 1 diabetes

Type 1 diabetes is recognised to include an element of insulin resistance. Insulin resistance is an independent risk factor for the development of macro- and microvascular complications of Type 1 diabetes and may also contribute to the development of the disease. This understanding comes at a time when the incidence of Type 1 diabetes appears to be rising and the public health burden from its vascular complications is high. A variety of safe and efficacious manoeuvres are available to redress insulin resistance in Type 2 diabetes. So far however, clinical trials addressing insulin resistance in Type 1 diabetes have been small with only short periods of follow-up. Regardless, these trials have yielded promising results. This review examines the evidence for insulin resistance in the pathophysiology of Type 1 diabetes and its complications, the problems associated with its measurement, and summarizes the trials aimed at reducing insulin resistance in Type 1 diabetes. This includes a meta-analysis of controlled trials of adjuvant metformin in Type 1 diabetes.

The addition of rosiglitazone to insulin in adolescents with type 1 diabetes and poor glycaemic control: a randomized-controlled trial

OBJECTIVE

To evaluate the effect of rosiglitazone, an insulin sensitizer, on glycaemic control and insulin resistance in adolescents with type 1 diabetes mellitus (T1DM) RESEARCH DESIGN AND METHODS: Randomized, double-blind, placebo-controlled crossover trial of rosiglitazone (4 mg twice daily) vs. placebo (24 wk each, with a 4 wk washout period). Entry criteria were diabetes duration >1 yr, age 10-18 yr, puberty (>or=Tanner breast stage 2 or testicular volume >4 mL), insulin dose >or=1.1 units/kg/day, and haemoglobin A1c (HbA1c) >8%. Responses to rosiglitazone were compared with placebo using paired t-tests.

RESULTS

Of 36 adolescents recruited (17 males), 28 completed the trial. At baseline, age was 13.6 +/- 1.8 yr, HbA1c 8.9 +/- 0.96%, body mass index standard deviation scores (BMI-SDS) 0.94 +/- 0.74 and insulin dose 1.5 +/- 0.3 units/kg/day. Compared with placebo, rosiglitazone resulted in decreased insulin dose (5.8% decrease vs. 9.4% increase, p = 0.02), increased serum adiponectin (84.8% increase vs. 26.0% decrease, p < 0.01), increased cholesterol (+0.5 mmol/L vs. no change, p = 0.02), but no significant change in HbA1c (-0.3 vs. -0.1, p = 0.57) or BMI-SDS (0.08 vs. 0.04, p = 0.31). Insulin sensitivity was highly variable in the seven subjects who consented to euglycaemic hyperinsulinaemic clamps. There were no major adverse effects attributable to rosiglitazone.

CONCLUSION

The addition of rosiglitazone to insulin did not improve HbA1c in this group of normal weight adolescents with T1DM.

Role of obesity in complicating and confusing the diagnosis and treatment of diabetes in children

The alarming increase in the prevalence of obesity in children in the United States and globally raises major concerns about its future adverse impact on public health. One outcome of this disturbing trend that is already evident is the rapidly increasing incidence of type 2 diabetes at all ages. This disease, once thought to be nonexistent in children, is increasing coincident with obesity. This article addresses the role that obesity plays in type 2 diabetes and also explores its effects on other types of diabetes that occur in childhood. The new challenges for physicians who formulate a differential diagnosis of diabetes in children are discussed. Also examined are modifications of traditional diabetes treatment that can be helpful in combating the insulin resistance associated with obesity and that use medications that are not traditionally used in this age group. Cases are presented to illustrate certain points. An underlying thesis suggests that specific classification may not be as important to the clinician as the understanding of pathophysiologic factors that contribute to hyperglycemia in individual patients. Recommendations are offered to the practitioner for diagnosing and treating the obese child or adolescent with diabetes.

Effect of pioglitazone treatment on behavioral symptoms in autistic children

Introduction

Autism is complex neuro-developmental disorder which has a symptomatic diagnosis in patients characterized by disorders in language/communication, behavior, and social interactions. The exact causes for autism are largely unknown, but is has been speculated that immune and inflammatory responses, particularly those of Th2 type, may be involved. Thiazolidinediones (TZDs) are agonists of the peroxisome proliferator activated receptor gamma (PPARγ), a nuclear hormone receptor which modulates insulin sensitivity, and have been shown to induce apoptosis in activated T-lymphocytes and exert anti-inflammatory effects in glial cells. The TZD pioglitazone (Actos) is an FDA-approved PPARγ agonist used to treat type 2 diabetes, with a good safety profile, currently being tested in clinical trials of other neurological diseases including AD and MS. We therefore tested the safety and therapeutic potential of oral pioglitazone in a small cohort of children with diagnosed autism.

Case description

The rationale and risks of taking pioglitazone were explained to the parents, consent was obtained, and treatment was initiated at either 30 or 60 mg per day p.o. A total of 25 children (average age 7.9 ± 0.7 year old) were enrolled. Safety was assessed by measurements of metabolic profiles and blood pressure; effects on behavioral symptoms were assessed by the Aberrant Behavior Checklist (ABC), which measures hyperactivity, inappropriate speech, irritability, lethargy, and stereotypy, done at baseline and after 3–4 months of treatment.

Discussion and evaluation

In a small cohort of autistic children, daily treatment with 30 or 60 mg p.o. pioglitazone for 3–4 months induced apparent clinical improvement without adverse events. There were no adverse effects noted and behavioral measurements revealed a significant decrease in 4 out of 5 subcategories (irritability, lethargy, stereotypy, and hyperactivity). Improved behaviors were inversely correlated with patient age, indicating stronger effects on the younger patients.

Conclusion

Pioglitazone should be considered for further testing of therapeutic potential in autistic patients.