Independent component and pathway-based analysis of miRNA-regulated gene expression in a model of type 1 diabetes.

BACKGROUND: Several approaches have been developed for miRNA target prediction, including methods that incorporate expression profiling. However the methods are still in need of improvements due to a high false discovery rate. So far, none of the methods have used independent component analysis (ICA). Here, we developed a novel target prediction method based on ICA that incorporates both seed matching and expression profiling of miRNA and mRNA expressions. The method was applied on a cellular model of type 1 diabetes. RESULTS: Microarray profiling identified eight miRNAs (miR-124/128/192/194/204/375/672/708) with differential expression. Applying ICA on the mRNA profiling data revealed five significant independent components (ICs) correlating to the experimental conditions. The five ICs also captured the miRNA expressions by explaining > 97% of their variance. By using ICA, seven of the eight miRNAs showed significant enrichment of sequence predicted targets, compared to only four miRNAs when using simple negative correlation. The ICs were enriched for miRNA targets that function in diabetes-relevant pathways e.g. type 1 and type 2 diabetes and maturity onset diabetes of the young (MODY). CONCLUSIONS: In this study, ICA was applied as an attempt to separate the various factors that influence the mRNA expression in order to identify miRNA targets. The results suggest that ICA is better at identifying miRNA targets than negative correlation. Additionally, combining ICA and pathway analysis constitutes a means for prioritizing between the predicted miRNA targets. Applying the method on a model of type 1 diabetes resulted in identification of eight miRNAs that appear to affect pathways of relevance to disease mechanisms in diabetes.

A comparison of twice-daily biphasic insulin aspart 70/30 and once-daily insulin glargine in persons with type 2 diabetes mellitus inadequately controlled on basal insulin and oral therapy: a randomized, open-label study.

OBJECTIVE: To compare efficacy and safety of biphasic insulin aspart 70/30 (BIAsp 30) with insulin (glargine) in type 2 diabetic patients who were not maintaining glycemic control on basal insulin and oral antidiabetic drugs. METHODS: In a 24-week, open-label, parallel-group trial, type 2 diabetic patients who were not maintaining glycemic control on basal insulin (glargine or neutral protamine Hagedorn) + oral antidiabetic drugs were randomly assigned to twice-daily BIAsp 30 + metformin or once-daily glargine + metformin + secretagogues (secretagogues were discontinued in the BIAsp 30 arm). RESULTS: One hundred thirty-seven patients were randomly assigned to the BIAsp 30 group and 143 patients were randomly assigned to the glargine group. Of 280 patients randomized, 229 (81.8%) completed the study. End-of-trial hemoglobin A1c reductions were -1.3% (BIAsp 30) vs -1.2% (glargine) (treatment difference: 95% confidence interval, -0.06 [-0.32 to 0.20]; P = .657). Of patients taking BIAsp 30, 27.3% reached a hemoglobin A1c level <7.0% compared with 22.0% of patients taking glargine (treatment difference: P = .388). Glucose increment averaged over 3 meals was lower in the BIAsp 30 arm (treatment difference: -17.8 mg/dL, P = .001). Fasting plasma glucose reductions from baseline were -13.8 mg/dL (BIAsp 30) vs -42.5 mg/dL (glargine) (P = .0002). Final minor hypoglycemia rate, insulin dose, and weight change were higher in the BIAsp 30 arm (6.5 vs 3.4 events/patient per year, P<.05; 1.19 vs 0.63 U/kg; and 3.1 vs 1.4 kg, P = .0004, respectively). CONCLUSIONS: Despite not receiving secretagogues, patients taking BIAsp 30 + metformin achieved similar hemoglobin A1c levels and lower postprandial plasma glucose compared with those receiving glargine + metformin + secretagogues. The large improvement in the glargine group suggests the patients were not true basal failures at randomization. While switching to BIAsp 30 improves glycemic control in this patient population, remaining on basal insulin and optimizing the dose may be equally effective in the short term.

Risk for nocturnal hypoglycemia with biphasic insulin aspart 30 compared with biphasic human insulin 30 in adults with type 2 diabetes mellitus: a meta-analysis.

BACKGROUND: Insulin is recommended as a second-line treatment after diet and metformin fail to reach and/or maintain glycemic targets considered to minimize the risk for long-term diabetic complications. Hypoglycemia and the fear of developing hypoglyce-mia, however, remain substantial barriers to the initiation and optimal use of insulin. OBJECTIVE: The aim of this study was to compare biphasic insulin aspart 30 (BIAsp 30) with biphasic human insulin 30 (BHI 30) with respect to glycemic control and the risk for hypoglycemia using a meta-analysis of clinical trials comparing these insulins in patients with type 2 diabetes mellitus (T2DM). METHODS: We included all published and unpublished, randomized, controlled trials in adult patients with T2DM (treatment duration > or = 12 weeks) for which individual patient data were available. All clinical databases and local trial registries of Novo Nordisk A/S (Soeborg, Denmark) were searched to identify clinical trials comparing the 2 products. The predefined primary end point of the study was the overall rate of nocturnal hypoglyce-mia (major, minor, and symptoms-only hypoglycemia occurring from 12:00-6:00 AM). Hypoglycemia was analyzed using a negative binomial distribution model, accounting for exposure time. Glycemic end points were analyzed at 12 to 16 weeks of treatment using ANCOVA, adjusting for baseline. Secondary safety end points were the rates of major hypoglycemia (hypoglycemia requiring third-party assistance), minor hypoglycemia (symptoms confirmed by plasma glucose [PG] <3.1 mmol/L), daytime hypoglycemia (major, minor, and symptoms-only hypoglycemia occurring from 6:01 AM-11:59 PM), overall hypoglycemia (the sum of all major, minor, and symptoms-only episodes), and change in weight from baseline to 12 to 16 weeks of treatment. Secondary efficacy end points were changes in glycosylated hemoglobin (HbA(1c)), fasting PG (FPG), postprandial PG increment (averaged over breakfast, lunch, and dinner), and insulin dose. RESULTS: Nine randomized, parallel or crossover trials were included (N = 1674; male sex, 57%; mean [SD] age, 61.0 [10.6] years; body mass index, 26.7 [4.6] kg/m(2); HbA(1c), 8.1% [1.4%]; duration of diabetes, 10.9 [7.9] years). Rates of overall hypoglycemia were not significantly different (rate ratio [RR] = 1.08; 95% CI, 0.94-1.24; P = NS) between treatments. BIAsp 30 had a 50% lower rate of nocturnal hypoglycemia than BHI 30 (RR = 0.50; 95% CI, 0.38-0.67; P < 0.01), whereas the rate of daytime hypoglycemia was 24% lower for BHI 30 (RR = 1.24; 95% CI, 1.08-1.43; P < 0.01). The likelihood of major hypo-glycemia was significantly lower with BIAsp 30 compared with BHI 30 (odds ratio = 0.45; 95% CI, 0.22-0.93; P < 0.05). BIAsp 30 was associated with reduced PPG increment (averaged over breakfast, lunch and dinner) compared with BHI 30 (treatment difference, -0.31; 95% CI, -0.49 to -0.07; P < 0.01). There was a significantly larger reduction in FPG associated with BHI 30 (treatment difference, 0.63; 95% CI, 0.31-0.95; P < 0.01). However, no significant treatment difference was found for HbA(1c) (treatment difference, 0.04; 95% CI, -0.02 to 0.10; P = NS). CONCLUSION: This meta-analysis found BIAsp 30 to be associated with a significantly lower rate of nocturnal and major hypoglycemia, but a significantly increased risk for daytime hypoglycemia, compared with BHI 30 at a similar level of HbA(1c) in patients with T2DM.

Comparison of insulin detemir and insulin glargine using a basal-bolus regimen in a randomized, controlled clinical study in patients with type 2 diabetes.

BACKGROUND: This treat-to-target study compared the efficacy and safety of insulin detemir (IDet) and insulin glargine (IGla) in a basal-bolus (insulin aspart) regimen in type 2 diabetes. METHODS: 385 patients were randomized 2 : 1 (IDet : IGla). Non-inferiority of IDet to IGla was determined by HbA(1c) 95% CI upper limit <0.4. RESULTS: IDet and IGla showed similar efficacy in HbA(1c) reduction at 26 weeks, as the non-inferiority criterion was met at 26 weeks (LS mean [Det-Gla]: 0.207; 95% CI: 0.0149,0.3995). It appeared that IGla in some cases did better than IDet in terms of HbA(1c), but the difference (0.207%) was not clinically meaningful. Based on the CONSORT guideline, non-inferiority analysis using the LOCF approach was inconclusive regarding possible inferiority of delta 0.4 (LS mean of [Det-Gla]: 0.307; 95% CI: 0.1023, 0.5109). HbA(1c) decreased significantly from baseline in IDet (-1.1% [26 weeks], -0.9% [LOCF], p < 0.001) and in IGla (-1.3% [26 weeks, LOCF], p < 0.001). Final HbA(1c) were 7.1% (26 weeks) and 7.3% (LOCF) in IDet, and 6.9% (26 weeks) and 7.0% (LOCF) in IGla. Final FPG were 130 mg/dL (26 weeks) and 135 mg/dL (LOCF) in IDet, and 134 mg/dL (26 weeks) and 137 mg/dL (LOCF) in IGla. There was significantly less weight gain in IDet-treated patients (1.2 +/- 3.96 kg versus 2.7 +/- 3.94 kg, p = 0.001). Hypoglycemia risk was comparable between groups. The majority of IDet-treated patients (87.4%) remained on a once-daily basal insulin regimen throughout the study. CONCLUSIONS: IDet and IGla were both effective and safe treatments for glycemic control in a basal-bolus regimen for type 2 diabetes. Clinically significant reductions in HbA(1c) were achieved in both groups, but with significantly less weight gain in the IDet group at comparable basal insulin dosage.

Efficacy and safety of biphasic insulin aspart 70/30 versus exenatide in subjects with type 2 diabetes failing to achieve glycemic control with metformin and a sulfonylurea.

OBJECTIVE: To compare safety and efficacy of biphasic insulin aspart 70/30 (BIAsp 30) with exenatide in subjects with type 2 diabetes mellitus (T2DM) not achieving glycemic targets with metformin and sulfonylurea in a randomized, open-label, 24-week trial. RESEARCH DESIGN AND METHODS: Subjects (N = 372, T2DM > 6 months, age > or = 18 and < or = 80 years, HbA1c > or = 8%, insulin naive not achieving glycaemic targets, receiving metformin and sulfonylurea) were randomized 1: 1: 1 to receive either BIAsp 30 QD (12 U before supper); BIAsp 30 BID (12 U divided equally between pre-breakfast and pre-supper); or exenatide (5 microg BID for 4 weeks and 10 microg BID thereafter). Efficacy (HbA1c, fasting plasma glucose [FPG]) and safety (adverse events and hypoglycemic episodes) were assessed. RESULTS: Glycemic control achieved with both BIAsp 30 BID and BIAsp 30 QD was superior to that with exenatide (BIAsp 30 BID-exenatide: HbA1c difference -0.91% [95% CI: -1.23 to -0.59%] and BIAsp 30 QD-exenatide: difference: -0.67% [95% CI: -0.99 to -0.34%]). At the end of the study, more subjects achieved HbA1c < 7% and < or = 6.5% in the BIAsp 30 BID group than in the exenatide group (HbA1c < 7%: 37% vs. 20%, p = 0.0060; HbA1c < or = 6.5%: 25% vs. 8%, p = 0.0004, respectively). Combined hypoglycemic episodes (major, minor, symptoms only) were reported by 56%, 61%, and 29% of the subjects in the BIAsp 30 QD, BIAsp 30 BID, and exenatide groups, respectively. Weight gain was observed in the BIAsp 30 group (BIAsp 30 QD: 2.85 kg, BIAsp 30 BID: 4.08 kg) and weight loss was observed in the exenatide group (-1.96 kg). Nausea or vomiting was responsible for discontinuation of seven subjects in the exenatide group and one subject in the BIAsp 30 BID group. CONCLUSIONS: Significantly more T2DM patients (poorly controlled with combination metformin/sulfonylurea) achieved glycemic goals when treated with BIAsp 30 than with exenatide. The high baseline HbA1c values (approximately 10.2%) and the long duration of diabetes (approximately 9 years) suggests that some subjects may have been in an advanced stage of their diabetes and may not have had sufficient beta-cell function for a GLP-1 mimetic to be effective. The insulin-treated groups had more minor hypoglycemic events and weight gain but less gastrointestinal side-effects. In summary, BIAsp 30 was more efficacious in helping patients with high baseline HbA1c achieve glycemic goals. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov, NCT00097877.