Multidisciplinary approach in the treatment of obesity (Self-financed project)

Duration of the project:

October 2011 – October 2014

Location:

University of Primorska, Faculty of Health Sciences and General Hospital Izola

Coordinator of the project:

Doc. Zala Jenko Pražnikar (SICRIS, ResearchGate)

Members of the research team:

Prof. Nadja Plazar (SICRIS, ResearchGate)
Mojca Bizjak, BSc (Dietetics) (SICRIS, ResearchGate)
Prof. Tamara Poklar Vatovec (SICRIS, ResearchGate)
Tadeja Jakus, BSc (Dietetics) (SICRIS, ResearchGate)
Prof. Mihaela Jurdana (SICRIS, ResearchGate)
Prof. Maša Černelič Bizjak (SICRIS, ResearchGate)
Sabina Ličen (SICRIS, ResearchGate)
Tamara Štemberger Kolnik (SICRIS, ResearchGate)
Ana Petelin(TRANS2CARE) (SICRIS, ResearchGate)
Maja Čemažar (TRANS2CARE) (SICRIS, ResearchGate)
Nataša Černič Šuligoj (ResearchGate)

ABSTRACT:

Financial support:

University of Primorska, Faculty of Health Sciences, 42 Polje, 6310 Izola and international project Cross-boarder cooperation Italy-Slovenia 2007-2013 (EU strategic project TRANS2CARE).

Scientific background and the aim of the project

The prevalence of overweight is increasing globally and has become a serious public health problem (1). Obesity is associated with low-grade chronic inflammation characterized by inflamed adipose tissue with increased macrophage infiltration. This inflammation is now widely believed to be the key link between obesity and development of insulin resistance and metabolic disease development (2).

Adipose tissue is crucial for the inflammatory status associated with obesity, primarily because of macrophage infiltration (3). Adipocytes secrete both pro- and anti-inflammatory adipokines, including pro-inflammatory tumor necrosis factor- (TNF-), interleukin-6 (IL-6), and the anti-inflammatory adiponectin. Reduced adiponectin and increased C-reactive protein (CRP) concentrations are associated with cardiovascular diseases and type 2 diabetes (4).

A reduction in inflammatory status may prevent the occurrence of disorders and diseases related to overweight. Many food compounds have been reported to have anti-inflammatory and/or antioxidant effects in various populations and the hypothesis is that these specific dietary components (polyunsaturated fatty acids (PUFAs), vitamin C, vitamin E, …) are able to reduce low-grade inflammation as well as metabolic and oxidative stress. For example anti-inflammatory effects of n–3 fatty acids have been shown by reduced plasma concentrations of CRP, TNF-, and IL-6 (5).

But the border between health and disease is often set by a complex equilibrium between two elements, genetics on one hand, and lifestyle (including diet) on the other (Figure 1). So, heterogeneity in circulating plasma concentrations of CRP, TNF-, IL-6, adiponectin, and other adipokines in response to specific dietary compounds may be due, in part, to genetics variations. Therefore at the same dietary intake of specific compound, their respective health effects may differ due to genetic differences (6).

Different polymorphisms, and biochemical measurements, will be determined in the study of obese people and matched controls, comparable in age and sex. Dietary intake will be assessed on the basis of a food frequency questionnaire, adapted to Slovenian dietary patterns and with dietary record. Each participant in the study will be individually discussed. The nutritional status will be assessed, resting metabolic rate with indirect calorimeter will be measured and the proportion and distribution of fat will be determined with bioelectrical impedance analysis. DNA will be isolated from peripheral white blood cells and genotyping of different polymorphisms will be performed by using real time polymerase chain reaction. For the quantitative determination of adipokines in human plasma ELISA method will be performed. Moreover, all biochemical analysis will be done at the biochemical laboratory at Izola General Hospital following established procedures. In the end all results will be analyzed and evaluated using different statistical programs. Using various statistical analyses the interactions between food components and genes will be calculated.

References:

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