ObjectiveThis study aimed to explore the role of nine microRNAs (miRNAs) in microparticles (MPs) on the efficacy of aerobic exercise in the regulation of inflammation and vascular function in obesity.MethodsSedentary women with normal weight (n = 6, BMI < 25 kg/m2) and women with obesity (n = 9, BMI > 30 kg/m2) were recruited at F. Hached Hospital (Sousse, Tunisia) and enrolled in an 8‐week aerobic program. Vascular function was assessed using laser Doppler flowmetry/iontophoresis, circulating MPs by flow cytometry, miRNAs by real‐time polymerase chain reaction, and inflammation by ELISA, before and after exercise.ResultsWomen with obesity presented with high prevalence of cardiovascular risk factors and a higher circulating MP level compared with healthy subjects. The MP miRNA profile was significantly different in the two groups. Exercise reduced BMI and inflammation in both groups and significantly improved endothelial‐dependent response (acetylcholine cutaneous vascular conductance) for healthy subjects, with a trend for women with obesity. Circulating MP level was increased after exercise, and miRNA expression was differentially modulated in both populations. Pearson analysis revealed a correlation between MPs miR‐124a and miR150 and adiponectin, TNFα, or IL‐6 levels.ConclusionsThe relation between MPs and miRNA profile, inflammation, vascular function, and exercise is of particular interest for defining “miRNA biomarker signature” in patients with cardiovascular disease who are potentially susceptible to respond to exercise.

ObjectiveTo explore the pathophysiological profile of patients who have obesity and to investigate the potential role of circulating microparticles (MPs) in endothelial dysfunction in patients who have obesity.MethodsThe inflammatory and oxidative status and the cutaneous microvascular blood flow were characterized in 69 patients with android obesity and 46 subjects with normal weight (controls) by using laser Doppler flowmetry. Circulating MP levels were measured by flow cytometry, and endothelial nitric oxide synthase (eNOS) and NADPH oxidase (NOX) expression in MPs was investigated by Western blotting. MP effect on vascular reactivity was assessed in rat aorta rings.ResultsPatients with obesity showed endothelial dysfunction, hyperglycemia, inflammation, and oxidative stress. In controls, low MP levels were positively correlated with normal microvascular function. Western blot analysis revealed reduced eNOS and increased NOX4D expression in MPs from subjects with obesity compared with controls. However, this was not correlated with endothelial dysfunction parameters and did not impair ex vivo endothelium-dependent vasodilation.ConclusionsThese results suggest that MPs do not contribute directly to endothelial dysfunction associated with obesity. Conversely, eNOS- and NOX-containing MPs could be involved in the compensatory mechanism of vascular endothelial cells to counteract the pathologic mechanisms underlying endothelial dysfunction.

Exercise training is known to stimulate vascular function and remodeling in a shear stress and inflammation dependent manner. Microparticles (MPs) released from vascular cells in response to shear stress, play a role in cell-cell crosstalk through carrying bioactive molecules such as miRNAs. Thus, the aim of our study was to explore whether exercise training impacts vascular wall cells and contributes to vascular function improvement through the modulation of inflammation molecules release. Therefore, we investigated the presence in MPs of 9 inflammation-regulatory miRNAs. A group of sedentary women (n=6, BMI<25Kg/m2) recruited at F. Hached Hospital (Sousse, Tunisia) was enrolled in an 8-weeks training program. Vascular function was assessed by Laser Doppler Flowmetry, oxidant stress and systemic inflammatory marker (CRPus) and selected circulating cytokines were measured. Furthermore, before and after exercise training, circulating MPs quantification by flow cytometry and miRNAs content by real-time PCR, were realized. While exercise training improved significantly the endothelial-dependent vasorelaxation, decreased systemic inflammation and modified the profile of circulating cytokines, circulating MPs level and oxidant stress remained unchanged. The miRNAs profile revealed that 1/ miR155 and miR302a were not detected in MPs neither before nor after training program; 2/ miR21, miR150, miR320a, miR146a, miR124a, miR126 and miR223 were expressed in circulating MPs of sedentary women; and 3/ after training program, a significant increase of miR21, miR146a, miR124a, miR150 and miR223 content was observed while miR126 and miR223 remained unchanged. Our results highlight the role of MPs as vehicle for miRNAs and the importance of inflammation-regulatory miRNAs as effectors in the vascular wall in order to generate an optimal vascular function and to control inflammation. The author hereby declares no conflict of interest

Microparticles (MPs) play essential roles in cell-cell crosstalk throw carrying bioactive molecules such as proteins and microRNAs (miRNAs). For this study, the MPs profile was explored in order to understand their implication in endothelial dysfunction in a group of obese (n=69, BMIε30Kg/m2) and normal weight subjects (n=46, BMI<25Kg/m2) recruited at F. Hached Hospital (Sousse, Tunisia). Vascular endothelial function was assessed by the exploration of the endothelium-dependent vasodilation by Laser Doppler Flowmetry. Circulating MPs were quantified by flow cytometry analysis. Firstly, endothelial dysfunction was detected by an impaired cutaneous vascular conductance (CVC) in obese patients in comparison to normal subjects, 0,34±0,03 versus 0,47±0,05 PU/mmHg respectively (p=0,029). Inflammation was significantly increased (CRPus x 3,5) as well as oxidant stress (AOPP, TBARS) in obese patients. On the other hand, enhanced circulating MPs levels were detected in obese patients 14792,6±1755,6 MPs/μl plasma in comparison to normal subjects 8480,7±1431,9 MPs/μl plasma (p=0,031). Therefore, we explored inflammation associated-miRNAs in MPs of sub-groups of obese (n=10) and normal subjects (n=10). The analysis of individual miRNAs (miR-150, miR- 146a, miR-320a, miR-124a, miR-223, miR-155, and miR-302a) was assessed by real time PCR. Among them, miR-150, miR-146a, miR-320a and miR- 124a were significantly enhanced in the obese group, miR-223 were identical in each group while miR-155a and miR-302a couldn’t be detected in MPs. Multivariate analyses revealed a positive correlation between miR-124a and CVC (r=0,807; p=0,009), and a positive correlation between miR320a and circulating MPs level (r=0,519; p=0,033). Our results are highlighting the importance of considering the MPs-containing miRNAs as effectors in the process of the endothelial dysfunction in obesity, however, more studies are necessary to understand the precise role these miRNAs.

OBJECTIVE:The endothelial nitric oxide synthase (NOS3) has been shown to play a role in the modulation of lipolysis. The goal of this study was to examine the impact of the G894T (rs1799983) and a 27 bp variable number of tandem repeats (VNTR 4a/b) of NOS3 gene on obesity in a sample of the Tunisian population. RESEARCH METHODS AND PROCEDURES:The study included 211 normal weight subjects and 183 obese patients. NOS3 G894T and 4a/b variants were determined by PCR analysis and examined for association with obesity-related traits. The effect of obesity on forearm skin blood flow (FSBF) response to acetylcholine, an endothelium-dependent vasodilator was determined by laser Doppler iontophoresis. RESULTS:In case-control studies, both G894T and 4a/b variants were associated with obesity. A significantly increased risk of obesity was found with the NOS3(G894T) TT genotype (OR:2.62, P=0.04). This association remains significant after adjustments for age and gender (OR: 2.93, P=0.03). A higher risk was also observed for carriers of the G894T allele (OR: 1.72, P=0.001). Stratified analysis by gender revealed that obese men (but not women) had significantly higher frequency of TT genotypes compared to controls (9.9% vs. 2.9%, P=0.01). Carriers of the 4b allele presented a significantly higher risk of obesity than non-carriers even after adjustments for age and gender (OR (95%CI): 1.72 (1.16-2.56), P=0.004). Correlations with anthropometric parameters revealed that carriers of TT and bb genotypes had significantly higher body mass index compared to those homozygous for the G and a alleles (P=0.0004). CONCLUSION:This study provides the first evidence for the association of G894T and 4a/b variants with body mass index and the risk of obesity in Tunisians. These polymorphisms did not exhibit, however any significant association with both metabolic traits and vascular function.

Obesity is a major worldwide health problem associated with several metabolic, inflammatory and oxidative troubles which represent major cardiovascular risk factors. The endothelial dysfunction plays a central role in the physiopathology of cardiovascular diseases. This critical function is generally evaluated through in vivo functional assessment, but emerging new biomarkers, like cell-derived microparticles (MPs,) reflecting alteration of the endothelium are increasingly studied. The aim of this study was to assess the level of circulating MPs in normal weight and obese patients and their relation with different oxidative, inflammatory and endothelial function parameters. Normal weight subjects (n=29, BMI<25kg/m2) and obese patients (n=53, BMI>30 kg/m2), were recruited at F. Hached Hospital (Sousse, Tunisia). Vascular endothelial function was assessed by the exploration of the endotheliumdependent vasodilatation by Laser Doppler Flowmetry and flow cytometry analysis was used for the quantification of circulating MPs. Obese subjects presented an endothelium-dependant vasodilatation significantly lower (21,26+2,89) than in normal weight patients (32,40+6,35) (p=0,008), characteristic to a vascular endothelial dysfunction. Furthermore, obese patients displayed a significantly higher number of circulating MPs (37579+4766 MPs/μl) in comparison to normal weight subjects (12099+934 MPs/μl) (p<0,001). Circulating MPs were positively correlated with anthropometric parameters BMI (r=0,504; p=0,02) and waist-hip ratio (WHC) (r=0,476; p=0,14). A positive correlation was also observed with parameters of inflammation (C-reactive protein (CRP) r=0,374; p=0,045) and oxidative stress (advanced oxidation protein product (AOPP) r=0,487; p=0,04 and total thiols r=0,551; p=0,01). These data demonstrated that circulating MPs could be a good biomarker of vascular endothelial dysfunction in obese patients, however the precise role of MPs in inflammation and oxidative stress has still to be clarified in further studies. Obesity, endothelial dysfunction, microparticles.

Breast cancer represents a major public health problem. Approximately one woman in ten is likely to develop a malignant tumor of the breast in their lifetime. The frequency of breast cancer is rising steadily for 20 years and the practical benefits in the diagnosis, prognosis and treatment of this disease are still too limited. Actually, there is no tumor marker with a specificity and sensitivity sufficient to have an utility in clinical and early diagnosis of breast cancer, although, carcinoembryonic antigen (CEA), MUC-1 and CA 15-3 were reported to be useful as markers for monitoring this disease. Thus, proteomics approaches are needed for the discovery and the identification of new protein biomarkers that may allow a better understanding of biological mechanisms of breast tumor development and serve as potential therapeutic targets. This article reviews advances in this field, as well as, the major contribution of these markers in breast pathology, with a focus on their biological characteristics and their clinical and therapeutic involvement.