When studying for a doctoral degree (PhD), candidates submit a thesis that provides a critical review of the current state of knowledge of the thesis subject as well as the student’s own contributions to the subject. The distinguishing criterion of doctoral graduate research is a significant and original contribution to knowledge.
Once accepted, the candidate presents the thesis orally. This oral exam is open to the public.
Obesity is the leading risk factors for type 2 diabetes. As such, understanding T2D pathology in obesity will provide novel insight into T2D prevention and treatment methods. The occurrence of T2D differs in males and females across the lifespan, therefore adipose tissue characteristics are suspected to differ between the sexes. Additionally, because a high waist to hip ratio is associated with T2D regardless of sex or age, it is conceivable that characteristics of upper body (abdominal subcutaneous adipose tissue (abSAT) and visceral adipose tissue (VAT)), and lower body (femoral SAT (fmSAT)) adipose tissue differs. Therefore, the objective of this thesis is to determine how sex and regional adipose tissue characteristics differ in T2D. To answer this objective a review of the literature, a novel flow cytometry protocol, and 3 experiments were conducted that resulted in one literature review, one methodology manuscript and three original research manuscripts were produced. Major findings include the first results showing that in females, not males, fmSAT had a greater T cells presence than abSAT. It was also shown that fmSAT T cells are greater in females with obesity and T2D (OB+T2D) than females with obesity (OB). No regional differences in macrophages, NK cells, iNKT cells or B cells were observed. Lastly, we are the first to show that abSAT and fmSAT impaired glucose uptake independent of effects on myogenesis. These results provide a launching ground for further study of fmSAT T cells and the cross talk between adipose tissue and skeletal muscle in T2D pathology. Our studies demonstrate how sex and regional adipose tissue contribute to T2D, knowledge that will ultimately allow for the development of more individualized T2D prevention and treatment methods.