Inflammation, adiposity, and progression of arterial stiffness in adolescents with type 1 diabetes: The SEARCH CVD Study

Risk factors for pre-clinical atherosclerosis in adolescents with type 1 diabetes

AIMS

To assess whether, besides "traditional" risk factors, overall oxidative stress, oxidized lipoproteins, and glycemic variability are associated with early macro-vascular damage in type 1 diabetes (T1D).

METHODS

In 267 children/adolescents with T1D (130 girls, age 9.1-23.0 years) we evaluated: derivatives of reactive oxygen metabolites [d-ROMs], serum total antioxidant capacity [TAC] and oxidized LDL-cholesterol [oxLDL]; markers of early vascular damage (Lipoprotein-associated phospholipase A2 [Lp-PLA2], z-score of carotid intima-media thickness [z-cIMT] and carotid-femoral pulse wave velocity [z-PWV]); CGM metrics of four weeks preceding the visit, central systolic/diastolic blood pressures (cSBP/cDBP), and HbA1c, z-score of BP (z-SBP/z-DBP) and circulating lipids longitudinally collected since T1D onset.. Three general linear models were built with z-cIMT, z-PWV adjusted for current cDBP, and Lp-PLA2 as independent variables.

RESULTS

The z-cIMT was associated with male gender (B = 0.491, η² = 0.029, p = 0.005), cSBP (B = 0.023, η² = 0.026, p = 0.008) and oxLDL (B = 0.022, η² = 0.022, p = 0.014). The z-PWV was associated with diabetes duration (B = 0.054, η² = 0.024, p = 0.016), daily insulin dose (B = 0.52, η² = 0.018, p = 0.045), longitudinal z-SBP (B = 0.18, η² = 0.018, p = 0.045) and dROMs (B = 0.003, η² = 0.037, p = 0.004). Lp-PLA2 was associated with age (B = 0.221, η² = 0.079, p = 3*10^-6), oxLDL (B = 0.081, η² = 0.050, p = 2*10^-4), longitudinal LDL-cholesterol (B = 0.031, η² = 0.043, p = 0.001) and male gender (B = -1.62, η² = 0.10, p = 1.3*10⁷).

CONCLUSIONS

Oxidative stress, male gender, insulin dose, diabetes duration and longitudinal lipids and blood pressure, contributed to the variance of early vascular damage in young patients with T1D.

Serum adipokine levels in patients with type 1 diabetes are associated with degree of obesity but only resistin is independently associated with atherosclerosis markers

PURPOSE

The role of adipokines in causing inflammation and insulin resistance in normal weight and obese patients is generally well studied. However, there are often conflicting results regarding their levels in type 1 diabetes mellitus (T1DM) patients and their relationship to micro- and macrovascular disease. We therefore investigated which serum adipokine levels are independently associated with markers of early atherosclerosis and microvascular complications in patients with T1DM.

METHODS

A cross-sectional study was performed in the Diabetes Outpatient Clinic of Hippokrateion General Hospital, Thessaloniki, Greece. Sixty T1DM patients (30 females, mean age 38.8 ± 10.6 years, mean diabetes duration 17.4 ± 9.9 years) were included. Plasma adiponectin, leptin, and resistin, carotid artery intima media thickness (cIMT), and arterial stiffness (pulse wave velocity, PWV/SpygmoCor CP System and Mobil-O-Graph 24 h PWA) were assessed.

RESULTS

Leptin and resistin levels were significantly higher in overweight and obese patients (p = 0.002 and p = 0.039, respectively). Adiponectin was the only adipokine negatively correlated with BMI (r_s =  - 0.41, p = 0.001). We report a bivariate association between serum adiponectin levels and retinopathy (p = 0.007). Resistin was the only adipokine that showed significant correlation with systolic (r_s = 0.42, p = 0.001) and diastolic (r_s = 0.29, p = 0.024) hypertension and PWV (p = 0.035).

CONCLUSIONS

Serum adipokine levels demonstrate similar bivariate associations with anthropometric variables in patients with T1DM to those in normal weight subjects. Although microvascular complications are associated with serum adipokine levels by bivariate analysis, only resistin, an inflammatory marker, is independently associated with arterial stiffness in patients with T1DM.

Cardiovascular disease in diabetes, beyond glucose

Despite the decades-old knowledge that diabetes mellitus is a major risk factor for cardiovascular disease, the reasons for this association are only partially understood. While this association is true for both type 1 and type 2 diabetes, different pathophysiological processes may be responsible. Lipids and other risk factors are indeed important, whereas the role of glucose is less clear. This lack of clarity stems from clinical trials that do not unambiguously show that intensive glycemic control reduces cardiovascular events. Animal models have provided mechanisms that link diabetes to increased atherosclerosis, and evidence consistent with the importance of factors beyond hyperglycemia has emerged. We review clinical, pathological, and animal studies exploring the pathogenesis of atherosclerosis in humans living with diabetes and in mouse models of diabetes. An increased effort to identify risk factors beyond glucose is now needed to prevent the increased cardiovascular disease risk associated with diabetes.

Role of Adiponectin and Tumor Necrosis Factor-Alpha in the Pathogenesis and Evolution of Type 1 Diabetes Mellitus in Children and Adolescents

Type 1 diabetes mellitus (T1DM) is a complex condition caused by the destruction of pancreatic beta cells by autoimmune mechanisms. As a result, insulin deficiency and subsequent hyperglycemia occur. The aim of the present study is to investigate the role of adiponectin and tumor necrosis factor alpha (TNF-α) in the development of T1DM. The study is designed as an observational case-control study, involving 52 diabetic patients and 66 controls. Z scores for Body Mass Index (BMI), weight, height, and adiponectin and TNF-α serum levels were assessed in both groups. The T1DM group had significantly higher TNF-α levels and a significantly higher proportion of high-risk patients for inflammation based on TNF-α values as compared to the control group, while both groups had statistically similar adiponectin levels and a similar proportion of high/medium-risk patients based on adiponectin values. TNF-α plays a significant role in the pathogenesis and evolution of T1DM and it may represent an additional marker of disease progression, as well as a potential target of immunotherapeutic strategies. In the present study, no statistically significant differences were recorded in adiponectin levels neither in diabetic patients and controls, nor in high/medium severity risk diabetic patients.

[Role of modified cardiovascular risk factors in development of oncologic diseases]

Cardiovascular (CVD) and oncological diseases (OD) are the main causes of death worldwide and account for a heavy burden on economy, disability and mortality in many countries. Clear understanding of the mechanisms shared by CVD and cancer is important for increasing the life span and quality of life in cancer survivors as well as for preventing comorbidities and correct instructing the patients about risk factors and lifestyle modifications. Both groups of diseases share risk factors, including smoking, obesity, diabetes mellitus, alcohol consumption, unhealthy diet, etc. Along with these factors, inflammation may play a key role as it promotes both types of diseases and accompanies obesity, diabetes mellitus, arterial hypertension, and dyslipidemia. Better understanding of the interaction between CVD and cancer will allow creating common effective diagnostic and preventive strategies and safe approaches to the treatment.

The Impact of Diabetes Mellitus on Cardiovascular Risk Onset in Children and Adolescents

The prevalence of diabetes mellitus is rising among children and adolescents worldwide. Cardiovascular diseases are the main cause of morbidity and mortality in diabetic patients. We review the impact of diabetes on establishing, during childhood and adolescence, the premises for cardiovascular diseases later in life. Interestingly, it seems that hyperglycemia is not the only factor that establishes an increased cardiovascular risk in adolescence. Other factors have been recognized to play a role in triggering the onset of latent cardiovascular diseases in the pediatric population. Among these cardiovascular risk factors, some are modifiable: glucose variability, hypoglycemia, obesity, insulin resistance, waist circumference, hypertension, dyslipidemia, smoking alcohol, microalbuminuria and smoking. Others are unmodifiable, such as diabetes duration and family history. Among the etiological factors, subclinical endothelial dysfunction represents one of the earliest key players of atherosclerosis and it can be detected during early ages in patients with diabetes. A better assessment of cardiovascular risk in pediatric population still represents a challenge for clinicians, and thus further efforts are required to properly identify and treat pediatric patients who may suffer from cardiovascular disease later in early adulthood.

The potential roles of Von Willebrand factor and neutrophil extracellular traps in the natural history of hypertrophic and hypertensive cardiomyopathy

Inflammation is often applied broadly to human disease. Despite its general familiarity, inflammation is highly complex. There are numerous injurious, immune and infectious determinants, functional elements and signaling pathways, ranging from genetic to epigenetic, environmental, racial, molecular and cellular that participate in disease onset and progression, phenotypic heterogeneity, and treatment selection and response. In addition, inflammation can be tissue and organ specific, adding a layer of complexity to achieving a detailed and translatable understanding of its role in health and disease. The following review takes a close look at inflammation in the context of two common heart diseases, hypertrophic cardiomyopathy and hypertensive cardiomyopathy.

HuangqiGuizhiWuwu Decoction Prevents Vascular Dysfunction in Diabetes via Inhibition of Endothelial Arginase 1

Hyperglycemia induces vascular endothelial dysfunction, which contributes to the development of vascular complication of diabetes. A classic prescription of traditional medicine, HuangqiGuizhiWuwu Decoction (HGWWD) has been used for the treatment of various cardiovascular and cerebrovascular diseases, which all are related with vascular pathology. The present study investigated the effect of HGWWD treatment in streptozocin (STZ)-induced vascular dysfunction in mouse models. In vivo studies were performed using wild type mice as well as arginase 1 knockout specific in endothelial cells (EC-A1-/-) of control mice, diabetes mice and diabetes mice treated with HGWWD (60 g crude drugs/kg/d) for 2 weeks. For in vitro studies, aortic tissues were treated with mice serum containing HGWWD with or without adenoviral arginase 1 (Ad-A1) transduction in high glucose (HG) medium. We found that HGWWD treatment restored STZ-induced impaired mean velocity and pulsatility index of mouse left femoral arteries, aortic pulse wave velocity and vascular endothelial relaxation accompanied by elevated NO production in the aorta and plasma, as well as reduced endothelial arginase activity and aortic arginase 1 expression. The protective effect of HGWWD is reversed by an inhibitor of nitric oxide synthesis. Meanwhile, the preventive effect of serum containing HGWWD in endothelial vascular dysfunction is completely blocked by Ad-A1 transduction in HG incubated aortas. HGWWD treatment further improved endothelial vascular dysfunction in STZ induced EC-A1-/- mice. This study demonstrates that HGWWD improved STZ-induced vascular dysfunction through arginase 1 - NO signaling, specifically targeting endothelial arginase 1.

The Role of the TGFβ Receptor Signaling Pathway in Adult Beta Cell Proliferation

Diabetes is a global epidemic and affects millions of individuals in the United States. Devising novel treatments for diabetes continues to be a great medical challenge. Postnatal beta cell growth or compensation is largely attributed to beta cell proliferation, which declines continuously with age. To boost beta cell proliferation to regenerate an adequate functional mass, there is a need to understand the signaling pathways that regulate beta cell proliferation for creating practical strategies to promote the process. Transforming growth factor β (TGFβ) belongs to a signaling superfamily that governs pancreatic development and the regeneration of beta cells after pancreatic diseases. TGFβ exerts its functions by activation of downstream Smad proteins and through its crosstalk with other pathways. Accumulating data demonstrate that the TGFβ receptor signaling pathway also participates in the control of beta cell proliferation. This review details the role of the TGFβ receptor signaling pathway in beta cell proliferation physiologically and in the pathogenesis of diabetes.