Long-term effects of lowering postprandial glucose level on cardiovascular outcomes in early-stage diabetic patients with coronary artery disease: 10-year post-trial follow-up analysis of the DIANA study.

AIMS: To elucidate the long-term cardiovascular benefit of lowering postprandial hyperglycemia (PPG) in early-stage T2DM patients. METHODS: This 10-year post-trial follow-up study included 243 patients from the DIANA (DIAbetes and diffuse coronary Narrowing) study, a multi-center randomized controlled trial which compared the efficacy of one-year life-style and pharmacological (voglibose/nateglinide) intervention lowering PPG on coronary atherosclerosis in 302 early-stage T2DM subjects [impaired glucose tolerance (IGT) or newly-diagnosed T2DM] (UMIN-CTRID#0000107). MACE (all-cause death, non-fatal MI or unplanned coronary revascularization) were compared in (1) three assigned therapies (life-style intervention/vogliose/nateglinide) and (2) patients with and without improvement of PPG (reversion from IGT to NGT or from DM to IGT/NGT on 75 g oral glucose tolerance test). RESULTS: During the 10-year post-trial observational period, voglibose (HR = 1.07, 95%CI: 0.69-1.66, p = 0.74) or nateglinide (HR = 0.99, 95%CI: 0.64-1.55, p = 0.99) did not reduce MACE. Similarly, achieving the improvement of PPG was not associated with a reduction of MACE (HR = 0.78, 95%CI: 0.51-1.18, p = 0.25). However, in IGT subjects (n = 143), this glycemic management significantly reduced the occurrence of MACE (HR = 0.44, 95%CI: 0.23-0.86, p = 0.01), especially unplanned coronary revascularization (HR = 0.46, 95%CI: 0.22-0.94, p = 0.03). CONCLUSIONS: The early improvement of PPG significantly reduced MACE and unplanned coronary revascularization in IGT subjects during the post-trial 10-year period.

The effect of Nateglinide and Octreotide on follicular morphology and free radical scavenging system in letrazole-induced rat model of PCOS.

OBJECTIVE: To investigate the effects of octreotide and nateglinide on ovarian follicle count, ovarian tissue damage, biochemical parameters and free radical scavenging system in letrazole-induced rat model of PCOS. MATERIALS AND METHODS: Forty-two female Sprague-Dawley rats were divided into six groups. Group 1 (Control Group): after localizing the ovaries and the uterine horns, the abdominal wall was closed without any surgical procedure. Group 2 (PCOS Group): PCOS was induced by administrating Letrozole orally for 21 successive days. At the end of 21 days, rats underwent ovarian biopsies. The experimental PCOS model was considered successful in the presence of atretic follicles without granulosa cell stratification. Group 3 (PCOS + Nateglinide Group): Nateglinide was administered by oral dropper for 30 days to the rats in which PCOS model was created. Group 4 (Nateglinid only Group): 30 days of NG was applied to the rats without PCOS. Group 5 (PCOS+Octreotide Group): 0.1 mg/kg/day Octreotide was given intraperitoneally for 4 weeks to the rats in which PCOS model was created. Group 6 (Octreotide only Group): animals without PCOS given 0.1 mg/kg/day Octreotide at the end of the treatment, bilateral oophorectomy was performed and blood samples were collected from all groups. Ovarian tissue was stained immunohistochemically with TLR-4 in addition to conventional staining. In addition to follicle classification, ovarian damage was graded. Serum insulin, FSH and LH, TNF-α, IL-6, SHBG, SOD, IGF-1, MDA and GSH levels were also measured. RESULTS: The cystic and degenerated follicle density of PCOS group was high compared with the other groups. Both cystic and degenerated follicles were significantly reduced in PCOS+NG and PCOS+OC groups compared to PCOS group. There was no difference between the groups in terms of serum LH, FSH and insulin levels (p>0.05). Serum testosterone level was significantly higher in the PCOS group compared to the other groups (p<0.01). Adding OC or NG to PCOS groups did not cause significant changes in testosterone levels. TNF-α and IL-6 levels were high in PCOS group (p<0.03). IGF-1 and MDA levels were higher in PCOS than in other groups (p<0.03, p<0.01 respectively). Adding OC or NG to the treatment normalized IGF-1 and MDA levels. Serum GSH levels were significantly lower in the PCOS group (p<0.05). Adding NG to the treatment increased GSH levels. CONCLUSIONS: Both NG and OCT reverses atretic and degenerate follicle damage due to PCOS through TLR-4, antioxidant and anti-inflammatory pathways.

PPARD rs2016520 (T/C) and NOS1AP rs12742393 (A/C) polymorphisms affect therapeutic efficacy of nateglinide in Chinese patients with type 2 diabetes mellitus.

BACKGROUND: Genetic polymorphisms in the PPARD and NOS1AP is associated with type 2 diabetes mellitus (T2DM); however, there is no evidence about its impact on the therapeutic efficacy of nateglinide. This study was designed to investigate a potential association of PPARD rs2016520 (T/C) and NOS1AP rs12742393 (A/C) polymorphisms with efficacy of nateglinide in newly diagnosed Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: Sixty patients with newly diagnosed T2DM were enrolled to identify PPARD rs2016520 and NOS1AP rs12742393 genotypes using the polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP). All subjects were treated with nateglinide (360 mg/day) for 8 weeks. Anthropometric measurements, clinical laboratory tests were obtained at baseline and after 8 weeks of nateglinide treatment. RESULTS: After nateglinide treatment for 8 consecutive weeks, patients with at least one C allele of PPARD rs2016520 showed a smaller decrease in post plasma glucose (PPG), homeostasis model assessment for beta cell function (HOMA-B) than those with the TT genotype did (P < 0.05). In patients with the AA genotype of NOS1AP rs12742393, the drug showed better efficacy with respect to levels of fasting plasma glucose (FPG), fasting serum insulin (FINS), HOMA-B and homeostasis model assessment for insulin resistance (HOMA-IR) than in patients with the AC + CC genotype (P < 0.05). NOS1AP rs12742393 genotype distribution and allele frequency were associated with responsiveness of nateglinide treatment (P < 0.05). CONCLUSIONS: The PPARD rs2016520 and NOS1AP rs12742393 polymorphisms were associated with nateglinide monotherapy efficacy in Chinese patients with newly diagnosed T2DM. TRIAL REGISTRATION: Chinese Clinical Trial Register ChiCTR13003536, date of registration: May 14, 2013.

Risk of Death and Heart Failure among Patients with Type 2 Diabetes Treated by Metformin and Nonmetformin Monotherapy: A Real-World Study.

BACKGROUND: To assess the association of metformin monotherapy with the risk of all-cause deaths and cardiovascular deaths and events in type 2 diabetes patients in real clinical practice. METHODS: This retrospective, observational study comprised patients with type 2 diabetes initially treated with metformin or nonmetformin monotherapy over 2011-2016. Data were extracted from the National Healthcare Big Data database in Fuzhou, China. Propensity score matching (PSM) was performed, matching each patient on metformin to one on nonmetformin in terms of a set of covariates. The primary endpoint was all-cause death, and secondary endpoints were cardiovascular death, heart failure, and heart failure hospitalization. Covariate-adjusted associations of metformin use with all the endpoints were assessed by Cox proportional hazards models. RESULTS: Among 24,099 patients, 5491 were initially treated with metformin and 18,608 with nonmetformin. PSM yielded 5482 patients in each cohort. During a median follow-up of 2.02 years, we observed 110 and 211 deaths in the metformin and nonmetformin groups, respectively. Metformin was significantly associated with reduced risk of all-cause death (adjusted hazard ratio (aHR) 0.52, 95% confidence interval (CI) 0.39-0.69), cardiovascular death (aHR 0.63, 95% CI 0.43-0.91), and heart failure (aHR 0.61, 95% CI 0.52-0.73), whereas the reduced risk in heart failure hospitalization was not statistically significant (aHR 0.70, 95% CI 0.47-1.02). CONCLUSIONS: In this analysis of electronic health record data from a large database in China, metformin as first-line monotherapy greatly reduced the risk of all-cause death, cardiovascular death, and heart failure in diabetes patients as compared with nonmetformin medications.

Nateglinide Exerts Neuroprotective Effects via Downregulation of HIF-1α/TIM-3 Inflammatory Pathway and Promotion of Caveolin-1 Expression in the Rat's Hippocampus Subjected to Focal Cerebral Ischemia/Reperfusion Injury.

Ischemic stroke is a major cause of death and motor disabilities all over the world. It is a muti-factorial disorder associated with inflammatory, apoptotic, and oxidative responses. Nateglinide (NAT), an insulinotropic agent used for the treatment of type 2 diabetes mellitus, recently showed potential anti-inflammatory and anti-apoptotic effects. The aim of our study was to elucidate the unique neuroprotective role of NAT in the middle cerebral artery occlusion (MCAO)-induced stroke in rats. Fifty-six male rats were divided to 4 groups (n = 14 in each group): the sham-operated group, sham receiving NAT (50 mg/kg/day, p.o) group, ischemia/reperfusion (IR) group, and IR receiving NAT group (50 mg/kg/day, p.o). MCAO caused potent deficits in motor and behavioral functions of the rats. Significant increase in inflammatory and apoptotic biomarkers has been observed in rats' hippocampi. Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway was significantly stimulated causing activation of series inflammatory biomarkers ending up neuro-inflammatory milieu. Pretreatment with NAT preserved rats' normal behavioral and motor functions. Moreover, NAT opposed the expression of hypoxia-inducible factor-1α (HIF-1α) resulting in downregulation of more inflammatory mediators namely, NF-κB, tumor necrosis factor-ß (TNF-ß), and the anti-survival gene PMAIP-1. NAT stimulated caveolin-1 (Cav-1) which prevented expression of oxidative biomarkers, nitric oxide (NO), and myeloperoxidase (MPO) and hamper the activation of apoptotic biomarker caspase-3. In conclusion, our work postulated that NAT exhibited its neuroprotective effects in rats with ischemic stroke via attenuation of different unique oxidative, apoptotic, and inflammatory pathways.

Risk of Hypoglycemia and Concomitant Use of Repaglinide and Clopidogrel: A Population-Based Nested Case-Control Study.

This nested case-control study evaluated the potential interaction between repaglinide and clopidogrel. Cases were defined by inpatient admissions or emergency department visits due to hypoglycemia. Concomitant use of repaglinide and clopidogrel within 3 days before the hypoglycemic event was the exposure of interest. For each case, up to four controls were randomly selected and matched by age, sex, type of glinide used (repaglinide or nateglinide), and time since cohort entry to the index date. Hypoglycemic risk was estimated by conditional logistic regressions. Concomitant use of repaglinide and clopidogrel was associated with an increased risk of hypoglycemia compared with repaglinide alone (adjusted odds ratio: 2.42; 95% confidence interval: 1.75-3.35). No significant associations were found with the two negative control object drug concomitants: nateglinide and clopidogrel and repaglinide and aspirin (without clopidogrel use). Our study suggests drug interaction between clopidogrel and repaglinide is clinically relevant and could increase the risk for hypoglycemia.

An outcome model approach to transporting a randomized controlled trial results to a target population.

OBJECTIVE: Participants enrolled into randomized controlled trials (RCTs) often do not reflect real-world populations. Previous research in how best to transport RCT results to target populations has focused on weighting RCT data to look like the target data. Simulation work, however, has suggested that an outcome model approach may be preferable. Here, we describe such an approach using source data from the 2 × 2 factorial NAVIGATOR (Nateglinide And Valsartan in Impaired Glucose Tolerance Outcomes Research) trial, which evaluated the impact of valsartan and nateglinide on cardiovascular outcomes and new-onset diabetes in a prediabetic population. MATERIALS AND METHODS: Our target data consisted of people with prediabetes serviced at the Duke University Health System. We used random survival forests to develop separate outcome models for each of the 4 treatments, estimating the 5-year risk difference for progression to diabetes, and estimated the treatment effect in our local patient populations, as well as subpopulations, and compared the results with the traditional weighting approach. RESULTS: Our models suggested that the treatment effect for valsartan in our patient population was the same as in the trial, whereas for nateglinide treatment effect was stronger than observed in the original trial. Our effect estimates were more efficient than the weighting approach and we effectively estimated subgroup differences. CONCLUSIONS: The described method represents a straightforward approach to efficiently transporting an RCT result to any target population.