Pioglitazone and risk of bladder cancer: a meta-analysis of controlled studies

Use of statins offsets insulin-related cancer risk

AIM

There is firm evidence of a relation between type 2 diabetes (T2DM) and increased risks of cancer at various sites, but it is still unclear how different antihyperglycaemic therapies modify site-specific cancer risks. The aim of this study was to provide a complete characterization of all possible associations between individual T2DM therapies, statin use and site-specific cancers in the Austrian population.

METHODS

Medical claims data of 1 847 051 patients with hospital stays during 2006-2007 were used to estimate age- and sex-dependent co-occurrences of site-specific cancer diagnoses and treatment with specific glucose-lowering drugs and statins.

RESULTS

Patients treated with insulin or insulin secretagogues showed up to ninefold increased risks for cancers of the colon [males only (m)], liver (m), pancreas, lung (m) and brain (m), as well as a strongly decreased risk for prostate cancer (m). In patients taking statins, the risks were generally decreased, with a greater risk reduction in patients not receiving antihyperglycaemic therapies. The strongest effects were observed for use of insulin and pancreatic cancer [m: OR 4.5, 95% CI: 3.1-6.6; females (f): OR 4.2, 95% CI: 2.5-7.1], sulfonylureas (m: OR 2.8, 95% CI: 1.7-4.6; f: OR 3.0, 95% CI: 2.1-4.2) or glitazones and skin cancer (f: OR 0.54, 95% CI: 0.36-0.80), as well as metformin and cancer of the prostate (m: OR 0.82, 95% CI: 0.75-0.91) and corpus uteri (f: OR 1.7, 95% CI: 1.4-2.0) and non-Hodgkin's lymphoma (f: OR 0.76, 95% CI: 0.64-0.91).

CONCLUSIONS

The use of statins offsets insulin-related cancer risks in patients with diabetes independently of sex and age. Overall, our data support the hyperglycaemia-cancer hypothesis. A reduction in endogenous or exogenous hyperinsulinaemia may be beneficial for cancer prevention. Therefore, insulin-sparing and insulin-sensitizing drugs should be the preferred treatment choices.

Pioglitazone and cardiovascular outcomes in patients with insulin resistance, pre-diabetes and type 2 diabetes: a systematic review and meta-analysis

OBJECTIVES

To evaluate the effect of pioglitazone in people with insulin resistance, pre-diabetes and type 2 diabetes.

DESIGN AND SETTING

Systematic review and meta-analysis of randomised, controlled trials.

DATA SOURCES

Literature searches were performed across PubMed, EMBASE, MEDLINE and Cochrane Central Register of Controlled Trials from 1966 to May 2016 to identify randomised, controlled trials with more than 1 year follow-up.

OUTCOME MEASURES

Relative risk (RR) with 95% CI was used to evaluate the association between pioglitazone and the risk of major adverse cardiovascular events (MACE: composite of non-fatal myocardial infarction, non-fatal stroke and cardiovascular death) and safety outcomes, after pooling data across trials in a fixed-effects model.

RESULTS

Nine trials with 12 026 participants were enrolled in the current meta-analysis. Pioglitazone therapy was associated with a lower risk of MACE in patients with pre-diabetes or insulin resistance (RR 0.77, 95% CI 0.64 to 0.93), and diabetes (RR 0.83, 95% CI 0.72 to 0.97). Risks of heart failure (RR 1.32; CI 1.14 to 1.54), bone fracture (RR 1.52, 95% CI 1.17 to 1.99), oedema (RR, 1.63; CI 1.52 to 1.75) and weight gain (RR 1.60; CI 1.50 to 1.72) increased in pioglitazone group.

CONCLUSIONS

Pioglitazone was associated with reduced risk of MACE in people with insulin resistance, pre-diabetes and diabetes mellitus. However, the risks of heart failure, bone fracture, oedema and weight gain were increased.

Nonalcoholic Fatty Liver Disease: Epidemiology, Pathogenesis, Natural History, Diagnosis, and Current Treatment Options

Nonalcoholic fatty liver disease (NAFLD) is on the rise and has become a major etiology for chronic liver disease. It is frequently associated with obesity, insulin resistance, hypertension, and dyslipidemia and is considered the hepatic manifestation of metabolic syndrome. In this review, we present a summary of the epidemiology and pathogenesis of NAFLD, and discuss the clinical evaluation and stratification of NAFLD patients into low, intermediate, and high risk with respect to liver-related outcomes. While diet and exercise are the cornerstone of treatment in all patients, the low rate of adherence and inadequacy of these recommendations necessitate pharmacologic intervention, especially in intermediate- and high-risk patients. We discuss vitamin E and pioglitazone which are often used as first-line therapy by many practitioners, with pentoxifylline and liraglutide as backup agents. Several drugs are in advanced-phase clinical trials and will likely change the landscape for management of NAFLD in the very near future.

Inhibition of ERK activity enhances the cytotoxic effect of peroxisome proliferator-activated receptor γ (PPARγ) agonists in HeLa cells

In this study, we examined whether the peroxisome proliferator-activated receptor γ (PPARγ) agonists, ciglitazone (CGZ) and troglitazone (TGZ), induce cell death in human cervical cancer HeLa cells. The cells were treated with a range of CGZ or TGZ doses for 24 or 48 h. Low concentrations of CGZ (≤10 μM) or TGZ (≤20 μM) had no effect on cell viability whereas higher doses induced cell death in a time- and dose-dependent manner as evidenced by the detection of activated caspase-3 and PARP cleavage. Treatment with the PPARγ antagonist GW9662 followed by PPARγ agonists did not increase CGZ- or TGZ-induced cell death, indicating that PPARγ agonists induced HeLa cell death independently of PPARγ. Moreover, ERK1/2 activation was observed at a CGZ concentration of 25 μM and a TGZ concentration of 35 μM, both of which induced cell death. To elucidate the role of ERK1/2 activated by the two PPARγ agonists, the effect of U0126, an inhibitor of ERK1/2, on PPARγ-agonist-induced cell death was examined. Treatment with 10 or 20 μM U0126 followed by CGZ or TGZ induced the down-regulation of ERK1/2 activity and a decrease in Bcl-2 expression accompanied by the collapse of mitochondrial membrane potential, which in turn significantly enhanced CGZ- or TGZ-induced apoptotic cell death. Our results suggest that PPARγ agonists are capable of inducing apoptotic cell death in HeLa cells independently of PPARγ and that inhibition of ERK1/2 activity offers a strategy to enhance the cytotoxicity of PPARγ agonists in the treatment of cervical cancer.

Insulin resistance and Parkinson's disease: A new target for disease modification?

There is growing evidence that patients with Type 2 diabetes have an increased risk of developing Parkinson's disease and share similar dysregulated pathways suggesting common underlying pathological mechanisms. Historically insulin was thought solely to be a peripherally acting hormone responsible for glucose homeostasis and energy metabolism. However accumulating evidence indicates insulin can cross the blood-brain-barrier and influence a multitude of processes in the brain including regulating neuronal survival and growth, dopaminergic transmission, maintenance of synapses and pathways involved in cognition. In conjunction, there is growing evidence that a process analogous to peripheral insulin resistance occurs in the brains of Parkinson's disease patients, even in those without diabetes. This raises the possibility that defective insulin signalling pathways may contribute to the development of the pathological features of Parkinson's disease, and thereby suggests that the insulin signalling pathway may potentially be a novel target for disease modification. Given these growing links between PD and Type 2 diabetes it is perhaps not unsurprising that drugs used the treatment of T2DM are amongst the most promising treatments currently being prioritised for repositioning as possible novel treatments for PD and several clinical trials are under way. In this review, we will examine the underlying cellular links between insulin resistance and the pathogenesis of PD and then we will assess current and future pharmacological strategies being developed to restore neuronal insulin signalling as a potential strategy for slowing neurodegeneration in Parkinson's disease.

Development of vascular complications and bladder carcinoma in diabetics using pioglitazone: A five-year Indian review

BACKGROUND

Pioglitazone has better cardiovascular outcomes and a questionable relationship with bladder carcinoma in diabetes mellitus, type II (DM-2). We sought to evaluate the role of pioglitazone in the Indian population.

METHODS

This is a retrospective study at an academic medical center in India. All DM-2 patients in 2008 with a new prescription of pioglitazone were age- and gender-matched with non-users. We excluded patients with gestational DM or DM type I. They were followed forward for five years and demographic data, micro- and macro-vascular complications, mortality, and bladder carcinoma were recorded. Two-tailed p ≤ 0.05 was considered statistically significant.

RESULTS

Two cohorts of 260 patients, with mean age of 58 ± 11 years with 413 (79.4%) males, were followed for five years. Pioglitazone users had higher hypertension, obesity, DM-2 family history (all p < 0.003), and use of insulin and oral hypoglycemics (all p < 0.0001) in comparison to non-users. HbA1c was not different between groups. Over five years, pioglitazone users had lesser retinopathy and myocardial infarctions (all p < 0.01). Five cases of bladder carcinoma were noted, all in the pioglitazone group, however without statistical significance. Baseline variables, including mean daily pioglitazone dose, were not statistically different between patients with and without bladder carcinoma. Nephropathy and MI were independent predictors for development of bladder carcinoma within pioglitazone users.

CONCLUSIONS

Pioglitazone users had significantly lesser myocardial infarctions and retinopathy despite more difficult to control DM 2. In an age- and gender-matched cohort of users and non-users, pioglitazone did not contribute to development of bladder cancer in the Indian population.

CONSENSUS STATEMENT BY THE AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY ON THE COMPREHENSIVE TYPE 2 DIABETES MANAGEMENT ALGORITHM--2015 EXECUTIVE SUMMARY

This document represents the official position of the American Association of Clinical Endocrinologists and the American College of Endocrinology. Where there were no randomized controlled trials or specific U.S. FDA labeling for issues in clinical practice, the participating clinical experts utilized their judgment and experience. Every effort was made to achieve consensus among the committee members. Position statements are meant to provide guidance, but they are not to be considered prescriptive for any individual patient and cannot replace the judgment of a clinician.

Generalized enrichment analysis improves the detection of adverse drug events from the biomedical literature

Background

Identification of associations between marketed drugs and adverse events from the biomedical literature assists drug safety monitoring efforts. Assessing the significance of such literature-derived associations and determining the granularity at which they should be captured remains a challenge. Here, we assess how defining a selection of adverse event terms from MeSH, based on information content, can improve the detection of adverse events for drugs and drug classes.

Results

We analyze a set of 105,354 candidate drug adverse event pairs extracted from article indexes in MEDLINE. First, we harmonize extracted adverse event terms by aggregating them into higher-level MeSH terms based on the terms’ information content. Then, we determine statistical enrichment of adverse events associated with drug and drug classes using a conditional hypergeometric test that adjusts for dependencies among associated terms. We compare our results with methods based on disproportionality analysis (proportional reporting ratio, PRR) and quantify the improvement in signal detection with our generalized enrichment analysis (GEA) approach using a gold standard of drug-adverse event associations spanning 174 drugs and four events. For single drugs, the best GEA method (Precision: .92/Recall: .71/F1-measure: .80) outperforms the best PRR based method (.69/.69/.69) on all four adverse event outcomes in our gold standard. For drug classes, our GEA performs similarly (.85/.69/.74) when increasing the level of abstraction for adverse event terms. Finally, on examining the 1609 individual drugs in our MEDLINE set, which map to chemical substances in ATC, we find signals for 1379 drugs (10,122 unique adverse event associations) on applying GEA with p < 0.005.

Conclusions

We present an approach based on generalized enrichment analysis that can be used to detect associations between drugs, drug classes and adverse events at a given level of granularity, at the same time correcting for known dependencies among events. Our study demonstrates the use of GEA, and the importance of choosing appropriate abstraction levels to complement current drug safety methods. We provide an R package for exploration of alternative abstraction levels of adverse event terms based on information content.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-016-1080-z) contains supplementary material, which is available to authorized users.

The role of PPARγ-mediated signalling in skin biology and pathology: new targets and opportunities for clinical dermatology

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that modulate the expression of multiple different genes involved in the regulation of lipid, glucose and amino acid metabolism. PPARs and cognate ligands also regulate important cellular functions, including cell proliferation and differentiation, as well as inflammatory responses. This includes a role in mediating skin and pilosebaceous unit homoeostasis: PPARs appear to be essential for maintaining skin barrier permeability, inhibit keratinocyte cell growth, promote keratinocyte terminal differentiation and regulate skin inflammation. They also may have protective effects on human hair follicle (HFs) epithelial stem cells, while defects in PPARγ-mediated signalling may promote the death of these stem cells and thus facilitate the development of cicatricial alopecia (lichen planopilaris). Overall, however, selected PPARγ modulators appear to act as hair growth inhibitors that reduce the proliferation and promote apoptosis of hair matrix keratinocytes. The fact that commonly prescribed PPARγ-modulatory drugs of the thiazolidine-2,4-dione class can exhibit a battery of adverse cutaneous effects underscores the importance of distinguishing beneficial from clinically undesired cutaneous activities of PPARγ ligands and to better understand on the molecular level how PPARγ-regulated cutaneous lipid metabolism and PPARγ-mediated signalling impact on human skin physiology and pathology. Surely, the therapeutic potential that endogenous and exogenous PPARγ modulators may possess in selected skin diseases, ranging from chronic inflammatory hyperproliferative dermatoses like psoriasis and atopic dermatitis, via scarring alopecia and acne can only be harnessed if the complexities of PPARγ signalling in human skin and its appendages are systematically dissected.

Obesity, Physical Activity and Bladder Cancer

While smoking and exposure to certain chemicals are well-defined risk factors for bladder cancer, there is no consensus as to the roles of modifiable lifestyle factors, notably physical activity, and obesity. We evaluated associations of obesity and physical activity with bladder cancer risk by performing a system-wide search of PubMed for cohort and case-control studies focused on obesity, exercise, and bladder cancer. A total of 31 studies were identified that evaluated the associations of obesity and physical activity with bladder cancer risk: 20 focused on obesity, eight on physical activity, and three on both. There was marked heterogeneity in population composition and outcomes assessment. Fifteen (65%) of the obesity studies used prevalence or incidence as the primary outcome and seven (30%) used bladder cancer mortality. Ten (44%) observed positive and 13 (56%) null associations of obesity with bladder cancer. Three (100%) of three studies also noted strong positive associations of obesity with bladder cancer progression or recurrence. Ten (91%) of the physical activity studies analyzed prevalence or incidence and one (9%) mortality. One (9%) study observed positive, seven (64%) null, and three (27%) negative associations of physical activity with bladder cancer. Study heterogeneity precluded quantitative assessment of outcomes. Obesity is potentially associated with an increased risk of bladder cancer, particularly for progression, recurrence, or death. Further studies of physical activity and bladder cancer are needed to validate these observations and elucidate the associations of exercise with bladder cancer progression and mortality.

PPARγ Antagonist Gleevec Improves Insulin Sensitivity and Promotes the Browning of White Adipose Tissue

Blocking phosphorylation of peroxisome proliferator-activated receptor (PPAR)γ at Ser(273) is one of the key mechanisms for antidiabetes drugs to target PPARγ. Using high-throughput phosphorylation screening, we here describe that Gleevec blocks cyclin-dependent kinase 5-mediated PPARγ phosphorylation devoid of classical agonism as a PPARγ antagonist ligand. In high fat-fed mice, Gleevec improved insulin sensitivity without causing severe side effects associated with other PPARγ-targeting drugs. Furthermore, Gleevec reduces lipogenic and gluconeogenic gene expression in liver and ameliorates inflammation in adipose tissues. Interestingly, Gleevec increases browning of white adipose tissue and energy expenditure. Taken together, the results indicate that Gleevec exhibits greater beneficial effects on both glucose/lipid metabolism and energy homeostasis by blocking PPARγ phosphorylation. These data illustrate that Gleevec could be a novel therapeutic agent for use in insulin resistance and type 2 diabetes.

Diabetes Pharmacotherapies and Bladder Cancer: A Medicare Epidemiologic Study

OBJECTIVE

Patients with type II diabetes have an increased risk of bladder cancer and are commonly treated with thiazolidinediones and angiotensin receptor blockers (ARBs), which have been linked to cancer risk. We explored the relationship between use of one or both of these medication types and incident bladder cancer among diabetic patients (diabetics) enrolled in Medicare.

RESEARCH DESIGN AND METHODS

We constructed both a prevalent and incident retrospective cohort of pharmacologically treated prevalent diabetics enrolled in a Medicare fee-for-service plan using inpatient, outpatient (2003-2011) and prescription (2006-2011) administrative data. The association of incident bladder cancer with exposure to pioglitazone, rosiglitazone and ARBs was studied using muitivariable Cox's hazard models with time-dependent covariates in each of the two cohorts.

RESULTS

We identified 1,161,443 prevalent and 320,090 incident pharmacologically treated diabetics, among whom 4433 and 1159, respectively, developed incident bladder cancers. In the prevalent cohort mean age was 75.1 years, mean follow-up time was 38.0 months, 20.2% filled a prescription for pioglitazone during follow-up, 10.4% received rosiglitazone, 31.6% received an ARB and 8.0% received combined therapy with pioglitazone + ARB. We found a positive association between bladder cancer and duration of pioglitazone use in the prevalent cohort (P for trend = 0.008), with ≥24 months of pioglitazone exposure corresponding to a 16% (95% confidence interval 0-35%) increase in the incidence of bladder cancer compared to no use. There was a positive association between bladder cancer and rosiglitazone use for <24 months in the prevalent cohort, but no association with ARB use. There were no significant associations in the incident cohort.

CONCLUSIONS

We found that the incidence of bladder cancer increased with duration of pioglitazone use in a prevalent cohort of diabetics aged 65+ years residing in the USA, but not an incident cohort.

High Sensitivity of an Ha-RAS Transgenic Model of Superficial Bladder Cancer to Metformin Is Associated with ∼240-Fold Higher Drug Concentration in Urine than Serum

While pharmacoepidemiologic and laboratory studies have supported the hypothesis that the antidiabetic drug metformin may be useful in treating or preventing cancer, there is limited evidence to suggest which specific cancer sites may be particularly sensitive. Sensitivity likely is determined both by features of tumor pathophysiology and by pharmacokinetic factors. We used UPII-mutant Ha-ras transgenic mice that develop hyperplasia and low-grade, papillary urothelial cell carcinoma to determine whether metformin has activity in a model of superficial bladder cancer. Metformin significantly improved survival, reduced urinary tract obstruction, reduced bladder weight (a surrogate for tumor volume), and led to clear activation of AMP α kinase and inhibition of mTOR signaling in neoplastic tissue. We investigated the basis of the unusual sensitivity of this model to metformin, and observed that following oral dosing, urothelium is exposed to drug concentrations via the urine that are approximately 240-fold higher than those in the circulation. In addition, we observed that bladder cancer cell lines (RT4, UMUC-3, and J82) with homozygous deletion of either TSC1 or PTEN are more sensitive to metformin than those (TEU2, TCCSUP, and HT1376) with wild-type TSC1 and PTEN genes. Our findings provide a strong rationale for clinical trials of oral metformin in treatment of superficial bladder cancer.

A pilot randomized controlled trial of pioglitazone for the treatment of poorly controlled asthma in obesity

BACKGROUND

Obese asthmatics tend to have poorly controlled asthma, and resistance to standard asthma controller medications. The purpose of this study was to determine the efficacy of pioglitazone, an anti-diabetic medication which can alter circulating adipokines and have direct effects on asthmatic inflammation, in the treatment of asthma in obesity.

METHODS

A two-center, 12-week, randomized, placebo-controlled, double-blinded trial. Treatments were randomly assigned with concealment of allocation. The primary outcome was difference in change in airway reactivity between participants assigned to pioglitazone versus placebo at 12 weeks.

RESULTS

Twenty-three participants were randomized to treatment, 19 completed the study. Median airway reactivity, measured by PC20 to methacholine was 1.99 (IQR 3.08) and 1.60 (5.91) mg/ml in placebo and pioglitazone group at baseline, and 2.37 (15.22) and 5.08 (7.42) mg/ml after 12 weeks, p = 0.38. There was no difference in exhaled nitric oxide, asthma control or lung function between treatment groups over the 12 week trial. Participants assigned to pioglitazone gained a significant amount more weight than those assigned to placebo (pioglitazone group mean weight 113.6, CI 94.5-132.7 kg at randomization and 115.9, CI 96.9-135.1 at 12 weeks; placebo mean weight 127.5, CI 108.4 - 146.6 kg at randomization and 124.5, CI 105.4 - 143.6 kg at 12 weeks; p = 0.04).

CONCLUSIONS

This pilot study suggests limited efficacy for pioglitazone in the treatment of poorly controlled asthma in obesity, and also the potential for harm, given the weight gain in those assigned to active treatment, and the association between increased weight and worse outcomes in asthma.

TRIAL REGISTRATION

Clinicaltrials.gov (NCT00634036).

Nephroprotection by Hypoglycemic Agents: Do We Have Supporting Data?

Current therapy directed at delaying the progression of diabetic nephropathy includes intensive glycemic and optimal blood pressure control, renin angiotensin-aldosterone system blockade and multifactorial intervention. However, the renal protection provided by these therapeutic modalities is incomplete. There is a scarcity of studies analysing the nephroprotective effect of antihyperglycaemic drugs beyond their glucose lowering effect and improved glycaemic control on the prevention and progression of diabetic nephropathy. This article analyzes the exisiting data about older and newer drugs as well as the mechanisms associated with hypoglycemic drugs, apart from their well known blood glucose lowering effect, in the prevention and progression of diabetic nephropathy. Most of them have been tested in humans, but with varying degrees of success. Although experimental data about most of antihyperglycemic drugs has shown a beneficial effect in kidney parameters, there is a lack of clinical trials that clearly prove these beneficial effects. The key question, however, is whether antihyperglycemic drugs are able to improve renal end-points beyond their antihyperglycemic effect. Existing experimental data are post hoc studies from clinical trials, and supportive of the potential renal-protective role of some of them, especially in the cases of dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors. Dedicated and adequately powered renal trials with renal outcomes are neccessary to assess the nephrotection of antihyperglycaemic drugs beyond the control of hyperglycaemia.

Obesity and Diabetes: The Increased Risk of Cancer and Cancer-Related Mortality

Obesity and type 2 diabetes are becoming increasingly prevalent worldwide, and both are associated with an increased incidence and mortality from many cancers. The metabolic abnormalities associated with type 2 diabetes develop many years before the onset of diabetes and, therefore, may be contributing to cancer risk before individuals are aware that they are at risk. Multiple factors potentially contribute to the progression of cancer in obesity and type 2 diabetes, including hyperinsulinemia and insulin-like growth factor I, hyperglycemia, dyslipidemia, adipokines and cytokines, and the gut microbiome. These metabolic changes may contribute directly or indirectly to cancer progression. Intentional weight loss may protect against cancer development, and therapies for diabetes may prove to be effective adjuvant agents in reducing cancer progression. In this review we discuss the current epidemiology, basic science, and clinical data that link obesity, diabetes, and cancer and how treating obesity and type 2 diabetes could also reduce cancer risk and improve outcomes.

Polemics of pioglitazone: an appraisal in 2015

Pioglitazone is an inexpensive and effective oral drug for the treatment of Type 2 diabetes. It addresses insulin resistance, one of the core pathophysiological defects in Type 2 diabetes, at both the adipose tissue and skeletal muscle level. As a majority of Type 2 diabetics classically exhibit higher insulin resistance, pioglitazone may strike exactly at the Achilles heel in this core pathogenesis. However, with the emerging association of bladder cancer with pioglitazone, French and German regulators were the first to ban or restrict pioglitazone use in 2011. The Indian regulators also suspended pioglitazone, although this ban was revoked within a month. Recently, a 10-year longitudinal study commissioned by US FDA found no association between bladder cancer and pioglitazone. Nevertheless, this controversy created a huge outcry in the medical fraternity. This review article is an overview of the development of this topic and an attempt to provide perspective on this contemporary issue.

Pharmacologic Therapy of Diabetes and Overall Cancer Risk and Mortality: A Meta-Analysis of 265 Studies

Different anti-diabetic medications (ADMs) may modify cancer risk and mortality in patients with diabetes. We conducted a systematic review and meta-analysis to estimate the magnitude of association and quality of supporting evidence for each ADM. A total of 265 studies (44 cohort studies, 39 case-control studies, and 182 randomized controlled trials (RCT)) were identified, involving approximately 7.6 million and 137,540 patients with diabetes for observational studies and RCTs, respectively. The risk of bias overall was moderate. Meta-analysis demonstrated that the use of metformin or thiazolidinediones was associated with a lower risk of cancer incidence (RR = 0.86, 95% CI 0.83-0.90, I² = 88.61%; RR = 0.93, 95% CI 0.91-0.96, I² = 0.00% respectively). On the other hand, insulin, sulfonylureas and alpha glucosidase inhibitor use was associated with an increased risk of cancer incidence (RR = 1.21, 95% CI 1.08-1.36, I² = 96.31%; RR = 1.20, 95% CI 1.13-1.27, I² = 95.02%; RR = 1.10, 95% CI 1.05-1.15, I² = 0.00% respectively). Use of other types of ADMs was not significantly associated with cancer risk. This study indicates that some ADMs may modify the risk of cancer in individuals with diabetes. Knowledge of this risk may affect the choice of ADM in individuals concerned about cancer or at increased risk for cancer.

Risk of bladder cancer in patients with diabetes: a retrospective cohort study

OBJECTIVE

The objective of this study was to examine the association between diabetes, and both urinary bladder cancer (UBC) risk and mortality.

METHODS

We conducted a retrospective cohort study using data from the UK Clinical Practice Research Datalink (CPRD) linked to the Office of National Statistics (ONS). Patients diagnosed with diabetes mellitus type 1 or 2, or using antidiabetic drugs (ADDs), were compared to matched non-diabetic controls. Cox proportional hazards models were used to estimate the risk and mortality of UBC. We adjusted for age, sex, smoking status and body mass index.

RESULTS

The cohort included 329,168 patients using ADD, and 307,315 controls with 1295 and 1071 patients, respectively, diagnosed as having UBC during follow-up. The adjusted HRs of UBC were 0.77 (95% CI 0.57 to 1.05) and 1.04 (95% CI 0.96 to 1.14) for type 1 and 2 diabetes, respectively. These results were similar if we restricted our analysis to an inception cohort. We noticed a small increased risk during the first year after diagnosis (HR=1.26 (95% CI 1.05 to 1.52)), which could be explained by detection bias. There was no influence of the severity of diabetes as measured by the glycated haemoglobin. Mortality of UBC was not increased for patients with either type 1 (HR=0.95 (95% CI 0.39 to 2.34)) or type 2 diabetes (HR=1.16 (95% CI 0.91 to 1.46)).

CONCLUSIONS

Neither the risk of UBC nor the mortality from UBC was increased in patients with type 1 and patients with type 2 diabetes in the CPRD data.

Pioglitazone and bladder cancer risk: a multipopulation pooled, cumulative exposure analysis

AIMS/HYPOTHESIS

The evidence on the association between pioglitazone use and bladder cancer is contradictory, with many studies subject to allocation bias. The aim of our study was to examine the effect of exposure to pioglitazone on bladder cancer risk internationally across several cohorts. The potential for allocation bias was minimised by focusing on the cumulative effect of pioglitazone as the primary endpoint using a time-dependent approach.

METHODS

Prescription, cancer and mortality data from people with type 2 diabetes were obtained from six populations across the world (British Columbia, Finland, Manchester, Rotterdam, Scotland and the UK Clinical Practice Research Datalink). A discrete time failure analysis using Poisson regression was applied separately to data from each centre to model the effect of cumulative drug exposure on bladder cancer incidence, with time-dependent adjustment for ever use of pioglitazone. These were then pooled using fixed and random effects meta-regression.

RESULTS

Data were collated on 1.01 million persons over 5.9 million person-years. There were 3,248 cases of incident bladder cancer, with 117 exposed cases and a median follow-up duration of 4.0 to 7.4 years. Overall, there was no evidence for any association between cumulative exposure to pioglitazone and bladder cancer in men (rate ratio [RR] per 100 days of cumulative exposure, 1.01; 95% CI 0.97, 1.06) or women (RR 1.04; 95% CI 0.97, 1.11) after adjustment for age, calendar year, diabetes duration, smoking and any ever use of pioglitazone. No association was observed between rosiglitazone and bladder cancer in men (RR 1.01; 95% CI 0.98, 1.03) or women (RR 1.00; 95% CI 0.94, 1.07).

CONCLUSIONS/INTERPRETATION

The cumulative use of pioglitazone or rosiglitazone was not associated with the incidence of bladder cancer in this large, pooled multipopulation analysis.

The ongoing pursuit of neuroprotective therapies in Parkinson disease

Many agents developed for neuroprotective treatment of Parkinson disease (PD) have shown great promise in the laboratory, but none have translated to positive results in patients with PD. Potential neuroprotective drugs, such as ubiquinone, creatine and PYM50028, have failed to show any clinical benefits in recent high-profile clinical trials. This 'failure to translate' is likely to be related primarily to our incomplete understanding of the pathogenic mechanisms underlying PD, and excessive reliance on data from toxin-based animal models to judge which agents should be selected for clinical trials. Restricted resources inevitably mean that difficult compromises must be made in terms of trial design, and reliable estimation of efficacy is further hampered by the absence of validated biomarkers of disease progression. Drug development in PD dementia has been mostly unsuccessful; however, emerging biochemical, genetic and pathological evidence suggests a link between tau and amyloid-β deposition and cognitive decline in PD, potentially opening up new possibilities for therapeutic intervention. This Review discusses the most important 'druggable' disease mechanisms in PD, as well as the most-promising drugs that are being evaluated for their potential efficiency in treatment of motor and cognitive impairments in PD.

Inflammatory therapeutic targets in coronary atherosclerosis-from molecular biology to clinical application

Atherosclerosis is the leading cause of death worldwide. Over the past two decades, it has been clearly recognized that atherosclerosis is an inflammatory disease of the arterial wall. Accumulating data from animal experiments have supported this hypothesis, however, clinical applications making use of this knowledge remain scarce. In spite of optimal interventional and medical therapy, the risk for recurrent myocardial infarction remains by about 20% over 3 years after acute coronary syndromes, novel therapies to prevent atherogenesis or treat atherosclerosis are urgently needed. This review summarizes selected potential molecular inflammatory targets that may be of clinical relevance. We also review recent and ongoing clinical trails that target inflammatory processes aiming at preventing adverse cardiovascular events. Overall, it seems surprising that translation of basic science into clinical practice has not been a great success. In conclusion, we propose to focus on specific efforts that promote translational science in order to improve outcome and prognosis of patients suffering from atherosclerosis.

Antihyperglycaemic therapies and cancer risk

AIMS

This review is aimed at highlighting the potential mitogenic/tumour growth-promoting or antimitogenic/tumour growth-inhibiting effects of the main antihyperglycaemic drug classes.

METHODS

We review and discuss the most current studies evaluating the association between antidiabetic medications used in clinical practice and malignancies as described so far.

RESULTS

Metformin seems to be the only antidiabetic drug to exert protective effects both on monotherapy and also when combined with other oral antidiabetic drugs or insulins in several site-specific cancers. In contrast, several other drug classes may increase cancer risk. Some reason for concern remains regarding sulphonylureas and also the incretin-based therapies regarding pancreas and thyroid cancers and the sodium glucose cotransporter-2 inhibitors as well as pioglitazone regarding bladder cancer. The majority of meta-analyses suggest that there is no evidence for a causal relationship between insulin glargine and elevated cancer risk, although the studies have been controversially discussed. For α-glucosidase inhibitors and glinides, neutral or only few data upon cancer risk exist.

CONCLUSION

Although the molecular mechanisms are not fully understood, a potential risk of mitogenicity and tumour growth promotion cannot be excluded in case of several antidiabetic drug classes. However, more large-scale, randomized, well-designed clinical studies with especially long follow-up time periods are needed to get reliable answers to these safety issues.

Residual effect of reductions in red blood cell count and haematocrit and haemoglobin levels after 10-month withdrawal of pioglitazone in patients with Type 2 diabetes

AIM

To investigate the recovery of thiazolidinedione-induced body weight gain and haematopoietic changes after stopping pioglitazone treatment in patients with Type 2 diabetes.

METHODS

This retrospective cohort study included 214 patients divided into three groups according to pioglitazone treatment status. The first study arm included patients who received pioglitazone for 38 months then interrupted this for 10 months (pioglitazone-interruption group). The second arm consisted of patients who received pioglitazone throughout the 48 months (pioglitazone-continuous group); the third arm included patients who had never received pioglitazone therapy (control group).

RESULTS

Red blood cell count and haematocrit and haemoglobin levels decreased significantly, while body weight increased in the two pioglitazone-treated groups as compared with the control group at 38 months. Multivariate regression analysis showed that the reductions in red blood cell count/haemoglobin levels were associated with pioglitazone use. In the pioglitazone-interruption group, no recoveries of red blood cells, or haematocrit or haemoglobin levels were observed after stopping pioglitazone for 10 months compared with the pioglitazone-continuous group, but body weight gain decreased to a level that was significantly lower than that in the pioglitazone-continuous group and did not differ significantly from the control group.

CONCLUSION

In this study, we observed a reversal of body weight gain but no recoveries in red blood cells or haematocrit or haemoglobin levels after stopping pioglitazone for 10 months in patients treated with pioglitazone for 38 months. This finding should prompt a reconsideration of the sustained effect of thiazolidinediones on the haematopoietic system in patients with Type 2 diabetes.

Thiazolidinediones and the promise of insulin sensitization in type 2 diabetes

Type 2 diabetes is caused by insulin resistance coupled with an inability to produce enough insulin to control blood glucose, and thiazolidinediones (TZDs) are the only current antidiabetic agents that function primarily by increasing insulin sensitivity. However, despite clear benefits in glycemic control, this class of drugs has recently fallen into disuse due to concerns over side effects and adverse events. Here we review the clinical data and attempt to balance the benefits and risks of TZD therapy. We also examine potential mechanisms of action for the beneficial and harmful effects of TZDs, mainly via agonism of the nuclear receptor PPARγ. Based on critical appraisal of both preclinical and clinical studies, we discuss the prospect of harnessing the insulin sensitizing effects of PPARγ for more effective, safe, and potentially personalized treatments of type 2 diabetes.

Thiazolidinediones under preclinical and early clinical development for the treatment of Parkinson's disease

INTRODUCTION

Current treatment of Parkinson's disease (PD) is limited to symptomatic dopaminergic therapy, while no interventions have been shown to slow down disease progression.

AREAS COVERED

The following article highlights a group of PPAR-γ agonists called thiazolidinediones (TZDs), which are currently being tested for a putative disease-modifying benefit in PD, using pioglitazone as a prototypic compound. PPAR-γ is highly expressed in neurons of the substantia nigra and CNS immune cells. Preclinical data in rodent and primate support an effect of TZDs in preventing and/or arresting neurodegeneration and development of motor symptoms. Although no data on the neuroprotective effect of TZDs is currently available, a clinical trial is ongoing where the primary objective is to assess pioglitazone's impact on the progression of PD. The trial is also evaluating the drug's safety concerns.

EXPERT OPINION

The efficacy data from clinical trials must be carefully weighed against the safety concerns. However, given the solid preclinical data, and since the safety data are not yet fully conclusive and limited to the diabetic population, PPAR-γ research in PD can continue with caution. Ideally, drug discovery and development efforts will lead to the identification of new compounds with reduced risk of peripheral side effects.

Physiological functions of peroxisome proliferator-activated receptor β

The peroxisome proliferator-activated receptors, PPARα, PPARβ, and PPARγ, are a family of transcription factors activated by a diversity of molecules including fatty acids and fatty acid metabolites. PPARs regulate the transcription of a large variety of genes implicated in metabolism, inflammation, proliferation, and differentiation in different cell types. These transcriptional regulations involve both direct transactivation and interaction with other transcriptional regulatory pathways. The functions of PPARα and PPARγ have been extensively documented mainly because these isoforms are activated by molecules clinically used as hypolipidemic and antidiabetic compounds. The physiological functions of PPARβ remained for a while less investigated, but the finding that specific synthetic agonists exert beneficial actions in obese subjects uplifted the studies aimed to elucidate the roles of this PPAR isoform. Intensive work based on pharmacological and genetic approaches and on the use of both in vitro and in vivo models has considerably improved our knowledge on the physiological roles of PPARβ in various cell types. This review will summarize the accumulated evidence for the implication of PPARβ in the regulation of development, metabolism, and inflammation in several tissues, including skeletal muscle, heart, skin, and intestine. Some of these findings indicate that pharmacological activation of PPARβ could be envisioned as a therapeutic option for the correction of metabolic disorders and a variety of inflammatory conditions. However, other experimental data suggesting that activation of PPARβ could result in serious adverse effects, such as carcinogenesis and psoriasis, raise concerns about the clinical use of potent PPARβ agonists.

Thiazolidinediones and associated risk of bladder cancer: a systematic review and meta-analysis

AIMS

To determine whether thiazolidinedione use is associated with a risk of bladder cancer.

METHODS

We searched MEDLINE and EMBASE in June 2012 (with PubMed update to July 2013) and conducted meta-analysis on the overall risks of bladder cancer with pioglitazone or rosiglitazone and the risk with different categories of cumulative dose or duration of drug use.

RESULTS

We screened 230 citations and included 18 studies, comprising five randomized controlled trials (RCTs) and 13 observational studies. Meta-analysis showed a significantly higher overall risk of bladder cancer with pioglitazone in RCTs [7878 participants; odds ratio (OR) 2.51, 95% confidence interval (CI) 1.09-5.80] and observational studies (>2.6 million patients; OR for 'ever' users vs. non-users 1.21, 95% CI 1.09-1.35). Subgroup analysis of observational studies by cumulative dose showed the risk of bladder cancer to be greatest with >28.0 g of pioglitazone (OR 1.64, 95% CI 1.28-2.12). A significantly increased risk was found with both 12-24 months (OR 1.41, 95% CI 1.16-1.71) and >24 months (OR 1.51, 95% CI 1.26-1.81) cumulative durations of pioglitazone exposure. No significant risk was seen with rosiglitazone in RCTs (OR 0.84, 95% CI 0.35-2.04) or 'ever' users vs. non-users in observational studies (OR 1.03, 95% CI 0.94-1.12); the evidence for any relationship between bladder cancer risk and rosiglitazone cumulative duration is limited and inconsistent. Direct comparison of pioglitazone to rosiglitazone 'ever' users yielded an OR of 1.25 (95% CI 0.91-1.72).

CONCLUSIONS

A modest but clinically significant increase in the risk of bladder cancer with pioglitazone was found, which appears to be related to cumulative dose and duration of exposure. We recommend that prescribers limit pioglitazone use to shorter durations.

Pioglitazone decreases asymmetric dimethylarginine levels in patients with impaired glucose tolerance or type 2 diabetes

BACKGROUND AND AIMS

Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is a biomarker and mediator of cardiovascular disease in patients with impaired glucose tolerance (IGT) or diabetes mellitus (DM). Advanced glycation end products (AGEs) and their receptor (RAGE) axis is involved in ADMA generation as well. However, it remains unclear whether pioglitazone could decrease ADMA levels by reducing RAGE expression in humans.

DESIGN AND METHODS

Forty-eight IGT or type 2 DM (T2DM) patients were assigned to receive either pioglitazone (n=29) or glimepiride (n=19) and evaluated at baseline and 16 weeks of follow-up. We compared the effects of pioglitazone and glimepride on ADMA and soluble form of RAGE (sRAGE) levels and then studied whether the changes in serum ADMA level (ΔADMA) after treatment with pioglitazone were correlated with ΔsRAGE. We further examined which Δclinical variables were independently associated with ΔADMA.

RESULTS

After 16-week treatments, fasting plasma glucose and glycated hemoglobin (HbA1c) values were comparably reduced in both groups. Compared with glimepiride, pioglitazone treatment significantly decreased ADMA levels and improved insulin sensitivity, while it elevated high-density lipoprotein cholesterol (HDL-C) and sRAGE values and increased body weight and waist circumference. In multiple stepwise regression analysis, log-transformed Δfibronectin were a sole independent determinant of log-transformed ΔADMA (r=-0.551, R²=0.303).

CONCLUSIONS

This study demonstrated that pioglitazone decreased serum ADMA levels in a glucose-lowering independent manner. Elevation of fibronectin by pioglitazone may contribute to the reduction of serum levels of ADMA in IGT or T2DM subjects, thus playing a protective role against cardiovascular disease.

Thiazolidinediones and the risk of asthma exacerbation among patients with diabetes: a cohort study

BACKGROUND

Thiazolidinediones are oral diabetes medications that selectively activate peroxisome proliferator-activated receptor gamma and have potent anti-inflammatory properties. While a few studies have found improvements in pulmonary function with exposure to thiazolidinediones, there are no studies of their impact on asthma exacerbations. Our objective was to assess whether exposure to thiazolidinediones was associated with a decreased risk of asthma exacerbation.

METHODS

We performed a cohort study of diabetic Veterans who had a diagnosis of asthma and were taking oral diabetes medications during the period of 10/1/2005 - 9/30/2006. The risk of asthma exacerbations and oral steroid use during 10/1/2006 - 9/30/2007 was compared between patients who were prescribed thiazolidinediones and patients who were on alternative oral diabetes medications. Multivariable logistic regression and negative binomial regression analyses were used to characterize this risk. A sensitivity analysis was performed, restricting our evaluation to patients who were adherent to diabetes therapy.

RESULTS

We identified 2,178 patients who were on thiazolidinediones and 10,700 who were not. Exposure to thiazolidinediones was associated with significant reductions in the risk of asthma exacerbation (OR = 0.79, 95% CI, 0.62 - 0.99) and oral steroid prescription (OR = 0.73, 95% CI 0.63 - 0.84). Among patients who were adherent to diabetes medications, there were more substantial reductions in the risks for asthma exacerbation (OR = 0.64, 95% CI 0.47 - 0.85) and oral steroid prescription (OR = 0.68, 95% CI 0.57 - 0.81).

CONCLUSIONS

Thiazolidinediones may provide a novel anti-inflammatory approach to asthma management by preventing exacerbations and decreasing the use of oral steroids.

Cardiovascular outcome trials of glucose-lowering drugs or strategies in type 2 diabetes

Few trials of glucose-lowering drugs or strategies in people with type 2 diabetes have investigated cardiovascular outcomes, even though most patients die from cardiovascular causes despite the beneficial effects of lipid-reducing and blood pressure-lowering treatments. The evidence-based reduction in risk of microvascular disease with glucose lowering has resulted in guidelines worldwide recommending optimisation of glycosylated haemoglobin, but no trial results have shown unequivocal cardiovascular risk reduction with glucose lowering. However, results of the post-trial follow-up of the UK Prospective Diabetes Study, and of a meta-analysis of the four glucose-lowering outcome trials completed to date, suggest about a 15% cardiovascular relative risk reduction per 1% decrement in HbA1c. The 2008 US Food and Drug Administration industry guidance for licensing of antidiabetic drugs greatly increased the number of cardiovascular outcome trials in diabetes, but most trials opted for non-inferiority designs aiming primarily to show absence of cardiovascular toxicity in the shortest possible time. This unintended consequence of the new regulations has meant that the potential long-term benefits, and the possible risks of new therapies, are not being assessed effectively. Also, essential head-to-head trials of therapies for this complex progressive disease, to answer issues such as how best to achieve and maintain optimum glycaemia without promoting weight gain or hypoglycaemia, are not being undertaken. In this Series paper, we summarise randomised controlled cardiovascular outcome trials in type 2 diabetes, provide an overview of ongoing trials and their limitations, and speculate on how future trials could be made more efficient and effective.

Nebulized PPARγ agonists: a novel approach to augment neonatal lung maturation and injury repair in rats

BACKGROUND

By stimulating lipofibroblast maturation, parenterally administered peroxisome proliferator-activated receptor γ (PPARγ) agonists promote lung homeostasis and injury repair in the neonatal lung. In this study, we determined whether PPARγ agonists could be delivered effectively via nebulization to neonates, and whether this approach would also protect against hyperoxia-induced lung injury.

METHODS

One-day old Sprague-Dawley rat pups were administered PPARγ agonists rosiglitazone (RGZ, 3 mg/kg), pioglitazone (PGZ, 3 mg/kg), or the diluent, via nebulization every 24 h; animals were exposed to 21% or 95% O2 for up to 72 h. Twenty-four and 72 h following initial nebulization, the pups were sacrificed for lung tissue and blood collection to determine markers of lung maturation, injury repair, and RGZ and PGZ plasma levels.

RESULTS

Nebulized RGZ and PGZ enhanced lung maturation in both males and females, as evidenced by the increased expression of markers of alveolar epithelial and mesenchymal maturation. This approach also protected against hyperoxia-induced lung injury, since hyperoxia-induced changes in bronchoalveolar lavage cell and protein contents and lung injury markers were all blocked by nebulized PGZ.

CONCLUSION

Nebulized PPARγ agonist administration promotes lung maturation and prevents neonatal hyperoxia-induced lung injury in both males and females.

Systematic reviews to ascertain the safety of diabetes medications

Clinicians and patients with type 2 diabetes enjoy an expanding list of medications to improve glycemic control. With this expansion has come a flurry of concerns about the safety of these antihyperglycemic agents, concerns that affect judgments about the risk/benefit balance of therapy. Some of these safety signals have been identified through the synthesis of existing research evidence. Thus, it has become important for clinicians and clinical policymakers to understand the strengths and limitations of systematic reviews and meta-analyses in determining the safety of diabetes medications. In this paper, we highlight key safety concerns with diabetes medications and discuss the role evidence synthesis plays in each, with special attention to its strengths and limitations.

Risk of bladder cancer among patients with diabetes treated with a 15 mg pioglitazone dose in Korea: a multi-center retrospective cohort study

It has not yet been determined whether chronic exposure to relatively low doses of pioglitazone increases risk of bladder cancer. We aimed to assess the risk of bladder cancer associated with pioglitazone in Korean patients. This was a retrospective cohort study of diabetic patients who had ≥ 2 clinic visits between November 2005 and June 2011 at one of four tertiary referral hospitals in Korea. A prevalent case-control analysis nested within the cohort was conducted to further adjust confounders. A total of 101,953 control patients and 11,240 pioglitazone-treated patients were included, in which there were 237 and 30 cases of incidental bladder cancer (64.9 and 54.9 per 100,000 person-years; age, sex-adjusted HR 1.135, 95% confidence interval [CI] 0.769-1.677), respectively. In the prevalent case-control analysis nested within the cohort, use of pioglitazone for a duration of > 6 months, but not ever use of pioglitazone, was associated with an increased rate of bladder cancer as compared to never use of pioglitazone. In conclusion, we failed to exclude the possible association between use of pioglitazone for a duration of > 6 months and bladder cancer.

A review on thiazolidinediones and bladder cancer in human studies

There is a concern of an increased risk of bladder cancer associated with the use of thiazolidinediones, a class of oral glucose-lowering drugs commonly used in patients with type 2 diabetes with a mechanism of improving insulin resistance. Human studies on related issues are reviewed, followed by a discussion on potential concerns on the causal inference in current studies. Pioglitazone and rosiglitazone are discussed separately, and findings from different geographical regions are presented. Randomized controlled trials designed for primarily answering such a cancer link are lacking, and evidence from clinical trials with available data for evaluating the association may not be informative. Observational studies have been reported with the use of population-based administrative databases, single-hospital records, drug adverse event reporting system, and case series collection. Meta-analysis has also been performed by six different groups of investigators. These studies showed a signal of higher risk of bladder cancer associated with pioglitazone, especially at a higher cumulative dose or after prolonged exposure; however, a weaker signal or null association is observed with rosiglitazone. In addition, there are some concerns on the causal inference, which may be related to the use of secondary databases, biases in sampling, differential detection, and confounding by indications. Lack of full control of smoking and potential biases related to study designs and statistical approaches such as prevalent user bias and immortal time bias may be major limitations in some studies. Overlapping populations and opposing conclusions in studies using the same databases may be of concern and weaken the reported conclusions of the studies. Because randomized controlled trials are expensive and unethical in providing an answer to this cancer issue, observational studies are expected to be the main source in providing an answer in the future. Furthermore, international comparison studies using well-designed and uniform methodology to clarify the risk in specific sexes, ethnicities, and other subgroups and to evaluate the interaction with other environmental risk factors or medications will be helpful to identify patients at risk.

Telmisartan ameliorates fibrocystic liver disease in an orthologous rat model of human autosomal recessive polycystic kidney disease

Human autosomal recessive polycystic kidney disease (ARPKD) produces kidneys which are massively enlarged due to multiple cysts, hypertension, and congenital hepatic fibrosis characterized by dilated bile ducts and portal hypertension. The PCK rat is an orthologous model of human ARPKD with numerous fluid-filled cysts caused by stimulated cellular proliferation in the renal tubules and hepatic bile duct epithelia, with interstitial fibrosis developed in the liver. We previously reported that a peroxisome proliferator activated receptor (PPAR)-γ full agonist ameliorated kidney and liver disease in PCK rats. Telmisartan is an angiotensin receptor blocker (ARB) used widely as an antihypertensive drug and shows partial PPAR-γ agonist activity. It also has nephroprotective activity in diabetes and renal injury and prevents the effects of drug-induced hepatotoxicity and hepatic fibrosis. In the present study, we determined whether telmisartan ameliorates progression of polycystic kidney and fibrocystic liver disease in PCK rats. Five male and 5 female PCK and normal control (+/+) rats were orally administered 3 mg/kg telmisartan or vehicle every day from 4 to 20 weeks of age. Treatment with telmisartan decreased blood pressure in both PCK and +/+ rats. Blood levels of aspartate amino transferase, alanine amino transferase and urea nitrogen were unaffected by telmisartan treatment. There was no effect on kidney disease progression, but liver weight relative to body weight, liver cystic area, hepatic fibrosis index, expression levels of Ki67 and TGF-β, and the number of Ki67- and TGF-β-positive interstitial cells in the liver were significantly decreased in telmisartan-treated PCK rats. Therefore, telmisartan ameliorates congenital hepatic fibrosis in ARPKD, possibly through the inhibition of signaling cascades responsible for cellular proliferation and interstitial fibrosis in PCK rats. The present results support the potential therapeutic use of ARBs for the treatment of fibrocystic liver disease in ARPKD patients.

Diabetes and cancer relationships

Diabetes and cancer are both heterogeneous and multifactorial diseases with tremendous impact on health worldwide. Epidemiologic evidence suggests that certain malignancies may be associated with diabetes, as well as with diabetes risk factors and, perhaps, with certain diabetes treatments. Numerous biological mechanisms could account for these relationships. Insulin-like growth factor (IGF)-1, IGF-2, IGF-1 receptors, insulin, and the insulin receptor play roles in the development and progression of cancers. Although evidence from randomized controlled trials does not support or refute associations of diabetes and its treatments with either increased or reduced risk of cancer incidence or prognosis, consideration of malignancy incidence rates and the magnitude of the trials that would be required to address these issues explains why such studies may not be readily undertaken.

Neuroprotection in multiple sclerosis: a therapeutic approach

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system that is pathologically characterized by inflammatory demyelination and neurodegeneration. Axonal damage, along with neuronal loss, occurs from disease onset and may lead to progressive and permanent disability. In contrast with the inflammatory pathways, the molecular mechanisms leading to MS neurodegeneration remain largely elusive. With improved understanding of these mechanisms, new potential therapeutic targets for neuroprotection have emerged. We review the current understanding of neurodegenerative processes at play in MS and discuss potential outcome measures and targets for neuroprotection trials.

Refocusing Peroxisome Proliferator Activated Receptor-α: A New Insight for Therapeutic Roles in Diabetes

Although glucose-lowering treatment shows some risk lowering effects in cardiovascular diseases, risks of macrovascular and microvascular complications have still remained, and development of new therapeutic strategies is needed. Recent data have shown that peroxisome proliferator activated receptor-α (PPAR-α) plays a pivotal role in the regulation of lipid homeostasis, fatty acid oxidation, cellular differentiation, and immune response such as inflammation or vascularization related to diabetic complication. This review will re-examine the metabolic role of PPAR-α, summarize data from clinical studies on the effect of PPAR-α agonist in diabetes, and will discuss the possible therapeutic role of PPAR-α activation.