Comparison of exenatide and acarbose on intra-abdominal fat content in patients with obesity and type-2 diabetes: A randomized controlled trial

A systematic review, meta-analysis, dose-response, and meta-regression of the effects of acarbose intake on glycemic markers in adults

Purpose

Prior research has yielded mixed results regarding the impact of acarbose intake on glycemic markers. To provide a more comprehensive analysis, a systematic review and meta-analysis was performed to compile data from various randomized controlled trials (RCTs) examining the effects of acarbose intake on fasting blood sugar (FBS), insulin, hemoglobin A1C (HbA1c), and homeostasis model assessment of insulin resistance (HOMA-IR) in adults.

Methods

To identify relevant literature up to April 2023, a comprehensive search was conducted on various scholarly databases, including PubMed, Web of Science, and Scopus databases. The effect size of the studies was evaluated using a random-effects model to calculate the weighted mean differences (WMD) and 95% confidence intervals (CI). Heterogeneity between studies was assessed using Cochran's Q test and I2.

Results

This systematic review and meta-analysis included a total of 101 RCTs with a total of 107 effect sizes. The effect sizes for FBS in milligrams per deciliter (mg/dl), insulin in picomoles per liter (pmol/l), hemoglobin A1C (HbA1c) in percentage (%), and homeostasis model assessment of insulin resistance (HOMA-IR) were 92, 46, 80, and 22, respectively. The pooled analysis indicated that acarbose intake resulted in significant decreases in FBS (p = 0.018), insulin (p < 0.001), HbA1c (p < 0.001), and HOMA-IR (p < 0.001).

Conclusion

The findings of this systematic review and meta-analysis suggest that acarbose intake can potentially lead to significant improvements in glycemic parameters by decreasing the levels of FBS, HbA1c, and insulin. However, larger and more rigorously designed studies are still needed to further evaluate and strengthen this association.

The effect of acarbose on inflammatory cytokines and adipokines in adults: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Although a large number of trials have observed an anti-inflammatory property of acarbose, the currently available research remains controversial regarding its beneficial health effects. Hence, the purpose of this study was to examine the effect of acarbose on inflammatory cytokines and adipokines in adults.

METHODS

PubMed, Web of Science, and Scopus were systematically searched until April 2023 using relevant keywords. The mean difference (MD) of any effect was calculated using a random-effects model. Weighted mean difference (WMD) and 95% confidence intervals (CIs) were calculated via the random-effects model.

RESULTS

The current meta-analysis of data comprised a total of 19 RCTs. Meta-analysis showed that acarbose significantly decreased tumor necrosis factor-alpha (TNF-α) (weighted mean difference [WMD]) = - 4.16 pg/ml, 95% confidence interval (CI) - 6.58, - 1.74; P = 0.001) while increasing adiponectin (WMD = 0.79 ng/ml, 95% CI 0.02, 1.55; P = 0.044). However, the effects of acarbose on TNF-α concentrations were observed in studies with intervention doses ≥ 300 mg/d (WMD = - 4.09; 95% CI - 7.00, - 1.18; P = 0.006), and the adiponectin concentrations were significantly higher (WMD = 1.03 ng/ml, 95%CI 0.19, 1.87; P = 0.016) in studies in which the duration of intervention was less than 24 weeks. No significant effect was seen for C-reactive protein (CRP; P = 0.134), interleukin-6 (IL-6; P = 0.204), and leptin (P = 0.576).

CONCLUSION

Acarbose had beneficial effects on reducing inflammation and increasing adiponectin. In this way, it may prevent the development of chronic diseases related to inflammation. However, more studies are needed.

Comparison of changes in adipokine and inflammatory cytokine levels in patients with newly diagnosed type 2 diabetes treated with exenatide, insulin, or pioglitazone: A post-hoc study of the CONFIDENCE trial

Background

Adipokines and inflammatory cytokines (ADICs) play important roles in type 2 diabetes mellitus (T2DM). This study aimed to compare the changes of ADIC levels (ΔADICs) in patients with newly diagnosed T2DM treated with different antihyperglycemic agents, and further investigate the impact of these changes on metabolic indices, β-cell function and insulin resistance (IR).

Methods

Four hundred and sixteen patients with newly diagnosed T2DM from 25 centers in China randomly received 48-week intervention with exenatide, insulin or pioglitazone. Anthropometric and laboratory data, indices of β-cell function and IR, and levels of AIDCs, including interleukin-1 beta (IL-1β), interferon-gamma (IFN-γ), leptin, and fibroblast growth factor 21 (FGF21) were detected at baseline and the end of the study.

Results

In total, 281 participants (68 % male, age: 50.3 ± 9.4 years) completed the study. After 48- week treatment, IL-1β and IFN-γ were significantly decreased with exenatide treatment (P < 0.001 and P = 0.001, respectively), but increased with insulin (P = 0.009 and P = 0.026, respectively). However, pioglitazone treatment had no impact on ADICs. No significant change in leptin or FGF21 was detected with any of the treatments. After adjustment for baseline values and changes of body weight, waist and HbA1c, the between-group differences were found in ΔIL-1β (exenatide vs. insulin: P = 0.048; and exenatide vs. pioglitazone: P = 0.003, respectively) and ΔIFN-γ (exenatide vs. insulin: P = 0.049; and exenatide vs. pioglitazone: P < 0.001, respectively). Multiple linear regression analysis indicated that Δweight was associated with ΔIL-1β (β = 0.753; 95 % CI, 0.137-1.369; P = 0.017). After adjusting for treatment effects, Δweight was also be correlated with ΔFGF21 (β = 1.097; 95%CI, 0.250-1.944; P = 0.012); furthermore, ΔHOMA-IR was correlated with Δleptin (β = 0.078; 95%CI, 0.008-0.147; P = 0.029) as well. However, ΔHOMA-IR was not significantly associated with ΔIL-1β after adjusting for treatment effects (P = 0.513).

Conclusion

Exenatide treatment led to significant changes of inflammatory cytokines levels (IL-1β and IFN-γ), but not adipokines (leptin and FGF21), in newly diagnosed T2DM patients. The exenatide-mediated improvement in weight and IR may be associated with a decrease in inflammatory cytokine levels.

The effect of acarbose on lipid profiles in adults: a systematic review and meta-analysis of randomized clinical trials

PURPOSE

Dyslipidemia, characterized by elevated levels of triglycerides (TG), low-density lipoprotein (LDL), total cholesterol (TC), and reduced levels of high-density lipoprotein (HDL), is a major risk factor for cardiovascular diseases (CVD). Several studies have shown the potential of acarbose in improving serum lipid markers. However, there have been conflicting results on the topic in adults. Therefore, a comprehensive systematic review and meta-analysis was conducted to assess the impact of acarbose on lipid profiles.

METHODS

The random-effects approach was used to combine the data, and the results were provided as weighted mean difference (WMD) with 95% confidence intervals (CI).

RESULTS

Our meta-analysis included a total of 74 studies with a combined sample size of 7046 participants. The results of the analysis showed that acarbose resulted in a reduction in levels of TG (WMD = - 13.43 mg/dl, 95% CI: - 19.20, - 7.67; P < 0.001) and TC (WMD = - 1.93 mg/dl, 95% CI: - 3.71, - 0.15; P = 0.033), but did not affect other lipid markers. When conducting a nonlinear dose-response analysis, we found that acarbose was associated with an increase in levels of HDL (coefficients = 0.50, P = 0.012), with the highest increase observed at a dosage of 400 mg/d. Furthermore, our findings suggested a non-linear relationship between the duration of the intervention and TC (coefficients = - 18.00, P = 0.032), with a decline observed after 50 weeks of treatment.

CONCLUSION

The findings of this study suggest that acarbose can reduce serum levels of TG and TC. However, no significant effects were observed on LDL or HDL levels.

The effects of GLP-1 receptor agonists on visceral fat and liver ectopic fat in an adult population with or without diabetes and nonalcoholic fatty liver disease: A systematic review and meta-analysis

AIM

To uncover the effect of GLP-1 receptor agonists (GLP-1 RAs) on the visceral- and hepatic fat content of adults.

METHODS

PubMed, EMBASE, Cochrane Library, and Web of Science were searched from inception until November 2022. Randomized controlled trials (RCTs) of GLP-1Ras was extracted, including reports of effects on visceral adipose tissue and hepatic fat content in individuals with type 2 diabetes, non-type 2 diabetes, NAFLD (non-alcoholic fatty liver disease), and non-NAFLD. Meta-analyses used random-effects models.

RESULTS

1736 individuals in the 30 qualified RCTs were included, comprising 1363 people with type 2 diabetes and 318 with NFLD. GLP-1 RAs reduced visceral adipose tissue (standard mean difference [SMD] = -0.59, 95% CI [-0.83, -0.36], P<0.00001) and hepatic fat content (weighted mean difference [WMD] = -3.09, 95% CI [-4.16, -2.02], P<0.00001) compared to other control treatment. Subgroup analysis showed that GLP-1Ras dramatically decreased visceral fat in patients with type 2 diabetes (SMD = -0.49, 95% CI [-0.69, -0.29] P<0.00001), NAFLD (SMD = -0.99, 95% CI [-1.64, -0.34] P = 0.003), non-type 2 diabetes (SMD = -1.38, 95% CI [-2.44, -0.32] P = 0.01), and non-NAFLD (SMD = -0.53, 95% CI [-0.78, -0.28] P<0.0001). GLP-1Ras reduced the liver fat level of type 2 diabetes (WMD = -3.15, 95% CI [-4.14, -2.15] P<0.00001), NAFLD (WMD = -3.83, 95% CI [-6.30, -1.37] P = 0.002), and type 2 diabetes with NAFLD (WMD = -4.27, 95% CI [-6.80, -1.74] P = 0.0009), while showed no impact on the hepatic fat content in non-Type 2 diabetes (WMD = -12.48, 95% CI [-45.19, 20.24] P = 0.45).

CONCLUSIONS

LP-1 RAs significantly reduce visceral- and liver fat content in adults.

The effects of acarbose treatment on cardiovascular risk factors in impaired glucose tolerance and diabetic patients: a systematic review and dose-response meta-analysis of randomized clinical trials

Acarbose (ACB) seems to be an effective drug in the management of cardiovascular risk factors. However, no previous meta-analysis of randomized controlled trials (RCTs) has been done to evaluate the effects of ACB on cardiovascular risk factors on impaired glucose tolerance (IGT), type 2 diabetes mellitus (T2D), and type 1 diabetes mellitus (T1D). We comprehensively searched electronic databases including Scopus, Web of Science, and PubMed for RCTs for related keywords up to September 2022. A random-effects model was used to estimate the weighted mean difference (WMD) and 95% confidence interval (CI). The pooled analysis demonstrated that ACB treatment had a significant effect on fasting blood glucose (FBG) (WMD = -3.55 mg/dL; 95%CI: -6.29, -0.81; p = 0.011), fasting insulin (WMD = -6.73 pmoL/L; 95%CI: -10.37, -3.10; p < 0.001), HbA1c [WMD = -0.32%; 95%CI: -0.45, -0.20; p < 0.001], body weight (WMD = -1.25 kg; 95%CI: -1.79, -0.75; p < 0.001), body mass index (BMI) (WMD = -0.64 kg/m2; 95%CI: -0.92, -0.37; p < 0.001), tumor necrosis factor-alpha (TNF-α) (WMD = -2.70 pg/mL, 95%CI: -5.25, -0.16; p = 0.037), leptin (WMD = -1.58 ng/mL; 95%CI: -2.82, -0.35; p = 0.012), alanine transaminase (ALT) (WMD = 0.71 U/L; 95%CI: -0.31, 1.85; p = 0.164), triglyceride (TG) (WMD = -13.89 mg/dL; 95%CI: -20.69, -7.09; p < 0.001), total cholesterol (TC) (WMD = -2.26 mg/dL; 95%CI: -4.18, -0.34; p = 0.021), systolic blood pressure (SBP) (WMD = -1.29 mmHg; 95%CI: -2.44, -0.15; p = 0.027), and diastolic blood pressure (DBP) (WMD = 0.02 mmHg; 95%CI: -0.41, 0.45; p = 0.925) in an intervention group, compared with a placebo group. The non-linear dose-response analysis showed that ACB reduces the TC in trial duration by >50 weeks, and 180 mg/day is more effective for the decrement of CRP. ACB can improve lipid profiles, glycemic indices, anthropometric indices, and inflammatory markers in T2D, T1D, and IGT patients.

An Exploratory Critical Review on TNF-α as a Potential Inflammatory Biomarker Responsive to Dietary Intervention with Bioactive Foods and Derived Products

This review collects and critically examines data on the levels of tumour necrosis factor-alpha (TNF-α) in lean, overweight and obese subjects, and the effects of intervention with different foods and food products containing bioactive constituents in overweight/obese individuals. We additionally explore the influence of different single nucleotide polymorphisms (SNPs) on TNF-α levels and compare the response to food products with that to some anti-obesity drugs. Our aim was to provide an overview of the variability, consistency, and magnitude of the reported effects of dietary factors on TNF-α, and to envisage the reliability of measuring changes in the levels of this cytokine as a biomarker responsive to food intervention in association with the reduction in body weight. Regarding the circulating levels of TNF-α, we report: (i) a large intra-group variability, with most coefficients of variation (CV%) values being ≥30% and, in many cases, >100%; (ii) a large between-studies variability, with baseline TNF-α values ranging from <1.0 up to several hundred pg/mL; (iii) highly variable effects of the different dietary approaches with both statistically significant and not significant decreases or increases of the protein, and the absolute effect size varying from <0.1 pg/mL up to ≈50 pg/mL. Within this scenario of variability, it was not possible to discern clear differentiating limits in TNF-α between lean, overweight, and obese individuals or a distinct downregulatory effect on this cytokine by any of the different dietary approaches reviewed, i.e., polyunsaturated fatty acids (PUFAs), Vitamin-D (VitD), mixed (micro)nutrients, (poly)phenols or other phytochemicals. Further, there was not a clear relationship between the TNF-α responses and body weight changes. We found similarities between dietary and pharmacological treatments in terms of variability and limited evidence of the TNF-α response. Different factors that contribute to this variability are discussed and some specific recommendations are proposed to reinforce the need to improve future studies looking at this cytokine as a potential biomarker of response to dietary approaches.

Effect of Glucagon-like Peptide-1 Receptor Agonists on Fat Distribution in Patients with Type 2 Diabetes: A Systematic Review and Meta-analysis

Aims/Introduction

Glucagon‐like peptide‐1 receptor agonists (GLP‐1Ras) are widely used to treat type 2 diabetes. They not only reduce glucose, but also have a positive effect on weight loss. However, few studies have reported the effect of GLP‐1Ras on fat distribution.

Materials and Methods

PubMed, Cochrane, Embase and ClinicalTrials.gov were searched for randomized controlled trials on GLP‐1Ras and type 2 diabetes, published from inception to June 2021. Our main outcomes were the reductions of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). Other anthropometric outcomes were also assessed. We used the Cochrane Collaboration tools to assess the risk of bias in the included studies. The quality of the evidence was assessed using the Grades of Recommendation, Assessment, Development and Evaluation profiler version 3.6. Review Manager 5.4.1 and Stata 16.0 were used for data analysis.

Results

A total of 10 studies involving 541 patients were included. Compared with the control groups, the GLP‐1Ras groups showed reductions in VAT (standard mean difference −0.54, 95% confidence interval [CI] −0.92, −0.17, I² = 79%, P = 0.005) and SAT (standard mean difference −0.44, 95% CI −0.60, −0.27, I² = 44%, P < 0.00001). In addition, bodyweight (weighted mean difference −3.59, 95% CI −4.30, −2.88, I² = 0%, P < 0.00001), waist circumference (weighted mean difference −3.09, 95% CI −4.66, −1.52, I² = 70%, P = 0.0001) and body mass index (weighted mean difference −1.11, 95% CI −1.35, −0.86, I² = 47%, P < 0.00001) were significantly decreased. According to the Grades of Recommendation, Assessment, Development and Evaluation approach, the level of evidence was low or moderate.

Conclusion

This study highlights that GLP‐1Ras, especially liraglutide and exenatide, might play an active role in fat distribution in patients with type 2 diabetes. After treatment with GLP‐1Ras, both VAT and SAT decreased, and the decrease of VAT was numerically greater than that of SAT.

Effect of glucagon-like peptide-1 receptor agonists on circulating levels of leptin and resistin: A meta-analysis of randomized controlled trials

AIM

Previous studies have found reduced concentrations of both leptin and resistin after glucagon-like peptide-1 receptor agonist (GLP-1 RA) treatment; however, the evidence in this field is inconclusive. Therefore, the aim of this meta-analysis of randomized controlled trials was to evaluate the effect of GLP-1 RA on both leptin and resistin levels.

METHODS

The present systematic review and meta-analysis included randomized controlled trials investigating the effect of GLP-1 RA on leptin and resistin concentrations. For this, PubMed-MEDLINE, Scopus, Web of Science, ClinicalTrials.gov, and Google Scholar databases were searched. A random-effects model and a sensitivity analysis were performed for meta-analysis.

RESULTS

Meta-analysis of 13 randomized controlled trials comprising 1,025 subjects indicated that administration of GLP-1 RA significantly decreases leptin (WMD: -4.85 ng/mL, 95% CI: -9.32, -0.38, p = 0.03) and resistin (WMD: -1.40 ng/mL, 95% CI: -2.78, -0.01, p = 0.05) serum levels. However, the effect size was sensitive to four studies for both leptin and resistin concentrations.

CONCLUSION

The results of this meta-analysis of randomized controlled trials suggest that GLP-1 RA therapy reduces both leptin and resistin levels.

Systematic review and meta-analysis for prevention of cardiovascular complications using GLP-1 receptor agonists and SGLT-2 inhibitors in obese diabetic patients

Patients with type 2 diabetes mellitus (T2DM) and obesity are at high risk of developing cardiovascular disease (CVD). Both glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose cotransporter (SGLT-2) inhibitors have been shown to prevent CVD in T2DM patients. Additionally, the two drugs reduce body mass. However, it is unknown which drug is more effective at reducing the risk of CVD in such patients. We searched Medline, EMBASE, and Cochrane Library records to February 20, 2021 and performed a network meta-analysis to compare the efficacy with which the drugs reduced the risk of major adverse cardiovascular events (MACE). We included 102,728 patients in 12 studies containing data of obesity subgroup analyses. In T2DM patients with obesity, GLP-1 RAs significantly reduced the risk of MACE versus placebo (relative risk, RR [95% confidence interval, CI]: 0.88 [0.81–0.96]), whereas SGLT-2 inhibitors showed a tendency (RR [95% CI]: 0.91 [0.83–1.00]). In an indirect comparison, GLP-1 RAs were not associated with a significant difference in MACE compared with SGLT-2 inhibitors (RR [95% CI]: 0.97 [0.85–1.09]). Thus, GLP-1 RAs are effective at preventing MACE than placebo in T2DM patients with obesity, although further studies are warranted to conclude their superiority to SGLT-2 inhibitors.

Impact of glucagon-like peptide-1 receptor agonists on adiponectin concentrations: A meta-analysis of randomized controlled trials

AIMS

Previous studies have reported an elevation in adiponectin concentrations using glucagon-like peptide-1 receptor agonists (GLP-1 RA) therapy; however, this possible pleiotropic effect is still uncertain. Thus, the objective of this meta-analysis of randomized controlled trials was to assess the impact of GLP-1 RA on adiponectin levels.

METHODS

This systematic review and meta-analysis included randomized controlled trials investigating the effect of GLP-1 RA on circulating adiponectin concentrations. Studies from PubMed, Web of Science, Scopus, and Google Scholar databases were included. A random-effects model and a sensitivity analysis using the leave 1-out method were conducted.

RESULTS

A meta-analysis of 20 randomized controlled trials involving 1497 individuals demonstrated a significant increase in adiponectin levels after GLP-1 RA administration (weighted mean difference [WMD]: 0.59 μg/mL, 95% confidence interval [CI]: 0.10, 1.08, P = .02). Particularly, liraglutide had a significant effect on adiponectin (WMD: 0.55 μg/mL, 95% CI: 0.04, 1.06, P = .04), while exenatide did not affect these concentrations (WMD: 0.60 μg/mL, 95% CI: -0.23, 1.42, P = .16).

CONCLUSION

GLP-1 RA treatment is associated with an increase in adiponectin levels.

Impact of Incretin-Based Therapies on Adipokines and Adiponectin

Adipokines are a family of hormones and cytokines with both pro- and anti-inflammatory effects released into the circulation to exert their hormonal effects. Adipokines are closely involved in most metabolic pathways and play an important modulatory role in lipid and carbohydrate homeostasis as they are involved in the pathophysiology of most metabolic disorders. Incretin-based therapy is a newly introduced class of antidiabetic drugs that restores euglycemia through several cellular processes; however, its effect on adipokines expression/secretion is not fully understood. In this review, we propose that incretin-based therapy may function through adipokine modulation that may result in pharmacologic properties beyond their direct antidiabetic effects, resulting in better management of diabetes and diabetes-related complications.

Anti-inflammatory properties of antidiabetic drugs: A "promised land" in the COVID-19 era?

Inflammation is implicated in the development and severity of the coronavirus disease 2019 (COVID-19), as well as in the pathophysiology of diabetes. Diabetes, especially when uncontrolled, is also recognized as an important risk factor for COVID-19 morbidity and mortality. Furthermore, certain inflammatory markers [i.e. C-reactive protein (CRP), interleukin-6 (IL-6) and ferritin] were reported as strong predictors of worse outcomes in COVID-19 positive patients. The same biomarkers have been associated with poor glycemic control. Therefore, achieving euglycemia in patients with diabetes is even more important in the era of the COVID-19 pandemic. Based on the above, it is clinically interesting to elucidate whether antidiabetic drugs may reduce inflammation, thus possibly minimizing the risk for COVID-19 development and severity. The present narrative review discusses the potential anti-inflammatory properties of certain antidiabetic drugs (i.e. metformin, pioglitazone, sitagliptin, linagliptin, vildagliptin, alogliptin, saxagliptin, liraglutide, dulaglutide, exenatide, lixisenatide, semaglutide, empagliflozin, dapagliflozin, canagliflozin), with a focus on CRP, IL-6 and ferritin.

Placebo-controlled randomised trial with liraglutide on magnetic resonance endpoints in individuals with type 2 diabetes: a pre-specified secondary study on ectopic fat accumulation

AIMS/HYPOTHESIS

The aim of this work was to assess the effect of liraglutide on ectopic fat accumulation in individuals with type 2 diabetes mellitus.

METHODS

This study is a pre-specified subanalysis of the MAGNetic resonance Assessment of VICTOza efficacy in the Regression of cardiovascular dysfunction In type 2 diAbetes mellitus (MAGNA VICTORIA) study, with primary endpoints being the effects of liraglutide on left ventricular diastolic and systolic function. The MAGNA VICTORIA study was a single-centre, parallel-group trial in 50 individuals with type 2 diabetes mellitus (BMI >25 kg/m²) who were randomly assigned (1:1, stratified for sex and insulin use) to receive liraglutide 1.8 mg once daily or placebo for 26 weeks, added to standard care. Participants, study personnel and outcome assessors were blinded to treatment allocation. The secondary endpoints of visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (SAT) and epicardial fat were measured with MRI. Hepatic triacylglycerol content (HTGC) and myocardial triacylglycerol content (MTGC) were quantified with proton MR spectroscopy. Between-group differences (change from baseline) were tested for significance using ANCOVA. Mean differences with 95% CIs were reported.

RESULTS

The trial was completed in 2016. Twenty-four participants were randomised to receive liraglutide and 26 to receive placebo. One patient in the liraglutide group withdrew consent before having received the study drug and was not included in the intention-to-treat analysis. Liraglutide (n = 23) vs placebo (n = 26) significantly reduced body weight (liraglutide 98.4 ± 13.8 kg to 94.3 ± 14.9 kg; placebo 94.5 ± 13.1 kg to 93.9 ± 13.2 kg; estimated treatment effect -4.5 [95% CI -6.4, -2.6] kg). HbA_1c declined in both groups without a significant treatment effect of liraglutide vs placebo (liraglutide 66.7 ± 11.5 mmol/mol to 55.0 ± 13.2 mmol/mol [8.4 ± 1.1% to 7.3 ± 1.2%]; placebo 64.7 ± 10.2 mmol/mol to 56.9 ± 6.9 mmol/mol [8.2 ± 1.0% to 7.5 ± 0.7%]; estimated treatment effect -2.9 [95% CI -8.1, 2.3] mmol/mol or -0.3 [95% CI -0.8, 0.2]%). VAT did not change significantly between groups (liraglutide 207 ± 87 cm² to 203 ± 88 cm²; placebo 204 ± 63 cm² to 200 ± 55 cm²; estimated treatment effect -7 [95% CI -24, 10] cm²), while SAT was reduced by a significantly greater extent with liraglutide than with placebo (liraglutide 361 ± 142 cm² to 339 ± 131 cm²; placebo 329 ± 107 cm² to 333 ± 125 cm²; estimated treatment effect -29 [95% CI -51, -8] cm²). Epicardial fat did not change significantly between groups (liraglutide 8.9 ± 4.3 cm² to 9.1 ± 4.7 cm²; placebo 9.6 ± 4.1 cm² to 9.6 ± 4.6 cm²; estimated treatment effect 0.2 [95% CI -1.5, 1.8] cm²). Change in HTGC was not different between groups (liraglutide 18.1 ± 11.2% to 12.0 ± 7.7%; placebo 18.4 ± 9.4% to 14.7 ± 10.0%; estimated treatment effect -2.1 [95% CI -5.3, 1.0]%). MTGC was not different after treatment with liraglutide (1.5 ± 0.6% to 1.2 ± 0.6%) vs placebo (1.3 ± 0.5% to 1.2 ± 0.6%), with an estimated treatment effect of -0.1 (95% CI -0.4, 0.2)%. There were no adjudicated serious adverse events.

CONCLUSIONS/INTERPRETATION

Compared with placebo, liraglutide-treated participants lost significantly more body weight. Liraglutide primarily reduced subcutaneous fat but not visceral, hepatic, myocardial or epicardial fat. Future larger studies are needed to confirm the results of this secondary endpoint study.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01761318.

FUNDING

This study was funded by Novo Nordisk A/S (Bagsvaerd, Denmark).

Beneficial Effects of Adiponectin on Glucose and Lipid Metabolism and Atherosclerotic Progression: Mechanisms and Perspectives

Circulating adiponectin concentrations are reduced in obese individuals, and this reduction has been proposed to have a crucial role in the pathogenesis of atherosclerosis and cardiovascular diseases associated with obesity and the metabolic syndrome. We focus on the effects of adiponectin on glucose and lipid metabolism and on the molecular anti-atherosclerotic properties of adiponectin and also discuss the factors that increase the circulating levels of adiponectin. Adiponectin reduces inflammatory cytokines and oxidative stress, which leads to an improvement of insulin resistance. Adiponectin-induced improvement of insulin resistance and adiponectin itself reduce hepatic glucose production and increase the utilization of glucose and fatty acids by skeletal muscles, lowering blood glucose levels. Adiponectin has also β cell protective effects and may prevent the development of diabetes. Adiponectin concentration has been found to be correlated with lipoprotein metabolism; especially, it is associated with the metabolism of high-density lipoprotein (HDL) and triglyceride (TG). Adiponectin appears to increase HDL and decrease TG. Adiponectin increases ATP-binding cassette transporter A1 and lipoprotein lipase (LPL) and decreases hepatic lipase, which may elevate HDL. Increased LPL mass/activity and very low density lipoprotein (VLDL) receptor and reduced apo-CIII may increase VLDL catabolism and result in the reduction of serum TG. Further, adiponectin has various molecular anti-atherosclerotic properties, such as reduction of scavenger receptors in macrophages and increase of cholesterol efflux. These findings suggest that high levels of circulating adiponectin can protect against atherosclerosis. Weight loss, exercise, nutritional factors, anti-diabetic drugs, lipid-lowering drugs, and anti-hypertensive drugs have been associated with an increase of serum adiponectin level.

Glucagon-like peptide-1 mimetics, optimal for Asian type 2 diabetes patients with and without overweight/obesity: meta-analysis of randomized controlled trials

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are desirable for diabetes, especially in patients with overweight/obesity. We aimed to determine whether GLP-1RAs exhibit different glucose-lowering efficacies between Asian type 2 diabetes (T2D) patients with and without overweight/obesity. Randomized controlled trials were searched in EMBASE, MEDLINE, CENTRAL, and ClinicalTrials.gov. Studies published in English with treatment duration ≥12 weeks and information on HbA1c changes were included. The studies were divided into normal body mass index (BMI) and overweight/obese groups according to baseline BMI. Among 3190 searched studies, 20 trials were included in the meta-analysis. The standardized mean differences in HbA1c change, fasting glucose change, and postprandial glucose change were equivalent between normal BMI and overweight/obese studies (p > 0.05). The relative risk of HbA1c < 6.5% target achievement in normal BMI trials (7.93; 95% confidence interval: 3.27, 19.20) was superior to that in overweight/obesity trials (2.23; 1.67, 2.97), with a significant difference (p = 0.020). Body weight loss (p = 0.572) and hypoglycemic risk(p = 0.920) were similar in the two groups. The glucose-lowering effects of GLP-1RAs were equivalent among Asian T2D patients. With their advantages for weight-loss or weight-maintenance, GLP-1RAs are optimal medicines for Asian T2D patients with and without overweight/obesity.