Studying Intestinal Microbiotas to Counter Obesity and Chronic Disease
The number of overweight or obese Canadians has soared over the past 30 years. The phenomenon, also observed in other industrialized countries, has become a significant issue in recent years. The latest data from the World Health Organization indicate that, in 2014, more than 1.9 billion adults worldwide were overweight, including 600 million who were obese. The pandemic isn’t sparing children and teens. In 2013, 42 million children worldwide under the age of five were overweight. This global problem is set to become the biggest health challenge of the 21st century.
Linked to major changes, such as urbanization and automation, that lead to overeating and physical inactivity, obesity contributes to increases in cardiovascular disease, diabetes, high blood pressure, stroke, pulmonary embolism, osteoarthritis and some cancers. In Canada, obesity comes with substantial costs. In 2015, Statistics Canada estimated that 3.5 million Canadians suffered from Type 2 diabetes, an obesity-linked metabolic disease that costs the country more than $14 billion.
Until now, research on the physiopathology of this complex health disorder has focused on endogenous and genetic factors that control our metabolism. The rise of genomic, proteomic, metabolomic and bioinformatic technologies has intensified recent research on energy metabolism, and contributed to better understanding about obesity and its complications.
Dr. Vincenzo Di Marzo, Canada Research Excellence Chair (CERC) in the Microbiome-Endocannabinoidome Axis in Metabolic Health, focuses on the integrated study of how the intestinal microbiome and the endocannabinoid system influence metabolic syndrome. The syndrome refers to the physiological signs that indicate increased risk for certain diseases, and is no longer defined solely by excess weight, but also by related variables, including belly fat, hypertriglyceridemia, low levels of high-density lipoproteins (or “good cholesterol”), high blood pressure, and hyperglycemia.
Di Marzo will study how the intestinal microbiome functions. This exogenous system is made up of micro-organisms operating symbiotically with the human body. These micro-organisms live in the gastrointestinal tract and make up our intestinal flora. They play a key role in various body functions, including metabolism and immunity. The make-up of our intestinal microbiome depends on our diet. So, studying how diet changes its structure and functions is important for letting us understand its effect on cardiometabolic health.
Working in this context, Di Marzo intends to expand our knowledge of the physiological and pathological role of intestinal micro-organisms. He aims to concentrate on an interesting area of study: the link between the intestinal microbiome and the endocannabinoid system, which, when stimulated, causes us to eat more and accumulate more fat. This system is a crucial player in controlling and managing energy metabolism, as it intervenes in all aspects of energy homeostasis, and its activity is modulated by stress factors and changes in diet. It is associated with a large number of lipid mediators that are biochemically similar to endocannabinoids and are composed of multiple molecular targets that, together, form the endocannabinoidome.
The CERC in the Microbiome-Endocannabinoidome Axis in Metabolic Health is the first research chair in the world devoted studying the intestinal microbiome, including its alterations; influence on obesity-related inflammation; and link to developing Type 2 diabetes, cardiometabolic diseases and related problems. Di Marzo’s goal is to find new therapeutic approaches and develop innovative nutritional and medical strategies.
Di Marzo’s research is benefiting from scientific expertise at the Université Laval’s faculties of medicine and of agriculture and food science, as well as the Centre de recherche de l’Institut universitaire de cardiologie et de pneumologie de Québec—renowned for its integrated studies on obesity and chronic, society-wide diseases. Di Marzo’s team also relies on expertise from the Institute of Nutrition and Functional Foods, recognized for its multidisciplinary work studying the composition and health effects of food, and the prevention of metabolic syndrome and other chronic, nutrition-related diseases.