Effect of basal insulin therapy on vascular endothelial function and adipokine profiles in people with Type 2 diabetes

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 metformin on adipokines levels: A systematic review and meta-analysis of randomized-controlled trials

BACKGROUND

Considering the role of adipokine on diseases related to metabolic syndrome and even chronic diseases, it seems necessary to investigate effective interventions on these factors. This study aimed to comprehensively investigate the effects of metformin on adipokines.

METHODS

A comprehensive search was conducted in five databases using established keywords. The purpose of this search was to uncover controlled studies that have examined the impact of metformin on adipokines, specifically leptin, adiponectin, and resistin. The random-effects model analysis was used to provide pooled weighted mean difference and 95% confidence intervals.

RESULTS

Forty-nine studies were included in this article. The pooled findings showed that that the administration of metformin significantly decreases leptin (WMD: -3.06 ng/ml, 95 % CI: -3.81, -2.30, P < 0.001) and resistin (WMD: -1.27 µg/mL, 95 % CI: -2.22, -0.31, P = 0.009) levels in different populations compared to the control group. However, no significant effect of this antidiabetic drug on adiponectin levels was reported. The results obtained from the subgroup results in the present study also showed that metformin in people with a BMI greater than 30 kg/m2 compared to a BMI ≤ 30 kg/m2 causes a significant decrease in leptin levels and an increase in adiponectin levels. Also, metformin in lower doses (≤1500 mg/day) and younger people (<30 years) causes a significant increase in adiponectin levels.

CONCLUSIONS

In general, considering the role of adipokines on metabolic disease and even chronic disease, this drug can be used as a potentially useful drug, especially in obese people, to improve these factors.

Vascular Aging: Assessment and Intervention

Vascular aging represents a collection of structural and functional changes in a blood vessel with advancing age, including increased stiffness, vascular wall remodeling, loss of angiogenic ability, and endothelium-dependent vasodilation dysfunction. These age-related alterations may occur earlier in those who are at risk for or have cardiovascular diseases, therefore, are defined as early or premature vascular aging. Vascular aging contributes independently to cardio-cerebral vascular diseases (CCVDs). Thus, early diagnosis and interventions targeting vascular aging are of paramount importance in the delay or prevention of CCVDs. Here, we review the direct assessment of vascular aging by examining parameters that reflect changes in structure, function, or their compliance with age including arterial wall thickness and lumen diameter, endothelium-dependent vasodilation, arterial stiffness as well as indirect assessment through pathological studies of biomarkers including endothelial progenitor cell, lymphocytic telomeres, advanced glycation end-products, and C-reactive protein. Further, we evaluate how different types of interventions including lifestyle mediation, such as caloric restriction and salt intake, and treatments for hypertension, diabetes, and hyperlipidemia affect age-related vascular changes. As a single parameter or intervention targets only a certain vascular physiological change, it is recommended to use multiple parameters to evaluate and design intervention approaches accordingly to prevent systemic vascular aging in clinical practices or population-based studies.

Comparative effectiveness and harms of long-acting insulins for type 1 and type 2 diabetes: A systematic review and meta-analysis

AIM

To review evidence comparing benefits and harms of long-acting insulins in patients with type 1 and 2 diabetes.

METHODS

MEDLINE and two Cochrane databases were searched during February 2018. Two authors selected studies meeting inclusion criteria and assessed their quality. Comparative studies of adult or paediatric patients with diabetes treated with insulin degludec, detemir or glargine were included. Meta-analysis was used to combine results of similar studies, and the I² statistic calculated to assess statistical heterogeneity.

RESULTS

Of 2534 citations reviewed, 70 studies met the inclusion criteria. No statistically significant differences in HbA1c were seen between any two insulins or formulations. Hypoglycaemia was less probable with degludec than with glargine, including nocturnal hypoglycaemia in type 1 (rate ratio 0.68, 95% CI 0.56-0.81) and type 2 diabetes (rate ratio 0.73, 95% CI 0.65-0.82), and severe hypoglycaemia in type 2 diabetes (relative risk 0.72, 95% CI 0.54-0.96). Patients with type 2 diabetes had higher rates of withdrawal because of adverse events when treated with detemir compared with glargine (relative risk 2.1, 95% CI 1.4-3.3). Adults taking detemir gained about 1 kg less body weight than those taking degludec (type 1) or glargine (type 2).

CONCLUSIONS

No differences in glycaemic control were seen between insulin degludec, detemir and glargine. Hypoglycaemia was less probable with degludec than glargine, and patients taking detemir gained less body weight than those given degludec or glargine. In type 2 diabetes, withdrawals as a result of adverse events were more probable with detemir than glargine.

Metabolic effects of antidiabetic drugs on adipocytes and adipokine expression

Several classes of antidiabetic agents have been developed that achieve their hypoglycemic outcomes via various molecular mechanisms. Adipose tissue is a major metabolic and energy-storing tissue and plays an important role in many metabolic pathways, including insulin signaling and insulin sensitivity. Adipose tissue monitors and regulates whole body homeostasis via production and release of potent proteins, such as adipokine and adiponectin, into the circulation. Therefore, any agent that can modulate adipocyte metabolism can, in turn, affect metabolic and glucose homeostatic pathways. Antidiabetic drugs are not only recognized primarily as hypoglycemic agents but may also alter adipose tissue itself, as well as adipocyte-derived adipokine expression and secretion. In the current review, we present the major evidence concerning routinely used antidiabetic agents on adipocyte metabolism and adipokine expression.