Macrophages in human obesity – the effect of laparoscopic gastric bypass surgery on subcutaneous adipose tissue inflammation
Thesis event information
Date and time of the thesis defence
Place of the thesis defence
Oulu University Hospital, auditorium 1
Topic of the dissertation
Macrophages in human obesity – the effect of laparoscopic gastric bypass surgery on subcutaneous adipose tissue inflammation
Doctoral candidate
M.D. Ville Palomäki
Faculty and unit
University of Oulu Graduate School, Faculty of Medicine, University of Oulu Graduate School, Faculty of Medicine, Medical Research Center Oulu
Subject of study
Medicine
Opponent
Docent Timo Heikkinen, Terveystalo
Custos
Professor Petri Lehenkari, Cancer and Translational Medicine Research Unit, Medical Research Center Oulu, Oulu University Hospital and University of Oulu
Macrophages in human obesity – the effect of laparoscopic gastric bypass surgery on subcutaneous adipose tissue inflammation
Excess weight and obesity relate to multiple comorbidities, lost quality of life and mortality and cause major burden to healthcare and society. Most obesity seems to trace to changes in lifestyle and the food environment in the last few decades. The comorbidities related to obesity are increasingly viewed as a result of low-grade inflammation characterizing the state of excess adiposity. On microscopic level, this associates with the infiltration of immune cells, particularly macrophages, into adipose tissue. Bariatric surgery and weight loss repeal these alterations.
In this thesis, two behaviorally distinct macrophage pools are identified in subcutaneous adipose tissue of subjects with obesity. Of these, only the macrophages associated with pyroptotic adipocyte deaths decreased after laparoscopic Roux-en-Y gastric bypass for obesity. These macrophages were also highly imbued by known pro-inflammatory proteins, NLRP3 inflammasome and Caspase-1 which are associated with type 2 diabetes and insulin resistance in adipose tissue. The surgery associated with a shift of adipocyte size towards smaller populations.
In addition, a novel method was developed for fat cell size and count analysis using free open-source software.
In this thesis, two behaviorally distinct macrophage pools are identified in subcutaneous adipose tissue of subjects with obesity. Of these, only the macrophages associated with pyroptotic adipocyte deaths decreased after laparoscopic Roux-en-Y gastric bypass for obesity. These macrophages were also highly imbued by known pro-inflammatory proteins, NLRP3 inflammasome and Caspase-1 which are associated with type 2 diabetes and insulin resistance in adipose tissue. The surgery associated with a shift of adipocyte size towards smaller populations.
In addition, a novel method was developed for fat cell size and count analysis using free open-source software.
Last updated: 23.1.2024