Vi Dam, Concordia University

Supervisor: Sylvia Santosa, Concordia University

At present, it is unclear why some obese people are more at risk for developing obesity-related comorbities such as cardiovascular disease and diabetes while others remain healthy. In people of similar gender, age, height and body weight, fat tissue characteristics such as cell size, cell number, and the presence of immune cells can vary considerably. The reason for this variability resides in a closer examination of fat tissue development in the body. Excess weight gain beginning in childhood results in the constant exposure of fat tissue to an inflammatory environment which may lead to a higher risk of obesity-related cardiovascular disease including hypertension, atherosclerosis, and coronary heart disease. Childhood obesity may therefore perpetuate the development of dysfunctional fat tissue from as you age. This project seeks to provide answers as to whether fat tissue metabolism and immune functions differ in people that have been persistently obese since childhood or only in adulthood. Additionally, the immune system’s response to excess weight gain, as well as the short-term versus long-term consequences of obesity and obesity-related cardiovascular disease risk factors will be explored.

For this study, adults with childhood-onset and those with adult-onset obesity will be recruited. Body composition (height, weight, fat content) will be assessed. Blood will be obtained in order to measure glucose and insulin levels, lipid concentrations, and immune cell and cytokine concentrations. These would be correlated to risk of cardiovascular disease. Arterial stiffness would be assessed for risk of cardiovascular events. Finally, fat tissue will be sampled in order to examine the quantity and presence of immune cells and immune cell markers. Differences in results between the two populations would be correlated to risk of cardiovascular disease. The knowledge gained from this project would further contribute greatly to obesity research as well as in the prevention and treatment of obesity-related pathologies. This proposed project would serve to 1) Identify targets for early detection strategies for populations at high risk for vascular diseases: the age of onset of obesity would provide insight into identifying differences in two specific populations at risk for cardiovascular disease (childhood-onset vs adult-onset obese).  These differences would highlight and contribute to research specific to each target population; and 2) this projects aims to recruit study cohorts allowing for the identification of novel biomarkers of microvascular dysfunction which could be used for early detection of vascular disease: cytokine and immune cell presence and activity in the blood vessels and fat tissue involved in obesity-related inflammation is still poorly understood, this project would provide further insight into the role of immune cell activity and their secreted cytokines which could reveal new markers of interest associated with increased risk of vascular disease.