Discoveries and Innovations
LEADERS IN THE STUDY OF PULMONARY EFFECTS OF THE ELECTRONIC CIGARETTE
The electronic cigarette, a system vaporizing a solution with nicotine and flavours, is generally perceived as safe. Its utilization has indeed tremendous exploded over the last few years; Canada and Quebec have not been immune. A Canadian survey estimated at more than half a million the number of electronic cigarette users in 2013 within a global market of more than $6 billion in 2014. However, the increase in the use of the electronic cigarette is inversely proportional to the knowledge of its effects on lung health. Without being too alarmists, many people compare this electronic cigarette period as the golden age of smoking in the forties and fifties, where the tobacco stick was considered harmless; years of research and epidemiologic studies clearly demonstrated the opposite.
In order to address this knowledge gap, unfortunately often subsidized by rather subjective beliefs and a very aggressive marketing, Dr. Mathieu Morissette’s team and those of Drs. Louis-Philippe Boulet and Caroline Duchaine in close collaboration, began considering the study of electronic cigarette pulmonary effects. It built one of the first animal exposure systems to electronic cigarette vapours in addition to initiate studies in healthy volunteers. This work has been able to demonstrate that, although without having important effects on pulmonary functions when acutely used (1 h), electronic cigarette vapours modify the circadian rhythm in lungs as well as the response to tobacco cigarette smoke. Since approximately 70% of electronic cigarette users are also active smokers, called “double users”, this work suggests that this phenomenon could be problematic over the long term.
The teams of Dr. Morissette, Boulet and Duchaine are continuing their work, particularly with Health Canada researchers, in order to predict potential lung problems related to the electronic cigarette use which, ultimately, can result in a safety framework based on scientific and objective data.
Photo: Mathieu C. Morissette, Ph. D.
SCIENTIFIC BREAKTHROUGH ON THE GENETIC ASPECT OF CARDIOVASCULAR DISEASES
Dr. Benoit Arsenault’s team published during the past year an important study showing that lifestyle can have a major impact on the cardiovascular risk. Even among some individuals with genetic factors of cardiovascular risk.
To achieve this, Dr. Arsenault’s team examined whether lifestyle factors (smoking, physical activity, healthy eating and obesity) could influence the cardiovascular risk in patients with lipoprotein(a) elevated blood concentrations. This marker is identified as one of the most important genetic factors for cardiovascular diseases. Achieved along with several international collaborators and conducted on more than 14,000 participants, this study revealed that the promotion of healthier lifestyles could reduce up to 70% the cardiovascular risk in patients with an elevated level of lipoprotein(a). The results of this study were published in the Atherosclerosis journal. According to the most recent data, nearly 20% of the population have lipoprotein(a) elevated blood concentrations. A lipoprotein in the bloodstream consisting of an LDL particle (also known as “bad cholesterol”) linked to another protein, called apolipoprotein A. These individuals have a cardiovascular risk two to four times higher than those with a lower level of lipoprotein(a).
Even though some perceive that not much can be done in the area of prevention in patients with a genetic predisposition to cardiovascular diseases, the results of this study confirm they have the opportunity to take concrete action to reduce their risk of developing these. In fact, they may positively affect their health by promoting healthy eating, by increasing their levels of physical activity, by not smoking and with an ideal body mass index. Let us remember that cardiovascular diseases remain today one of the top killers in Canada. Some factors may increase the cardiovascular risk such as smoking, blood cholesterol, hypertension, type 2 diabetes, physical inactivity poor nutrition and abdominal obesity. Research in the field of cardiology at the Institute is increasingly interested in the genetic and environmental aspects of cardiovascular prevention.
The work of Dr. Arsenault is funded partially by the IUCPQ Foundation. These grants gave him the necessary lever in the procurement of external funding to put forth a study that will target some families from the area in order to better understand the genetic aspects of cardiovascular diseases. His current research projects will also focus on understanding mechanisms by which the lipoprotein(a) could cause cardiovascular diseases and identifying new therapeutic options reducing the circulating level of this protein in patients at high risk of these.
Photo: Benoît Arsenault, Ph. D.
THE CONSTANTLY EVOLVING BARIATRIC SURGERY
The increasing prevalence of obesity, observed in many parts of the world, has been extensively documented in the media and in the scientific press over the past several decades. The most current predictions indicate that by 2025, the prevalence of among adults in Canada will hover around 26–29% in men and women. Dealing with such a progression of how many people with obesity, the scientific and medical community showed a growing interest for the understanding, the prevention and the treatment of this condition and metabolic diseases that are frequently associated to it. Even though lifestyle-specific approaches must remain of primary importance, in the arsenal of available treatments toward reducing the burden of obesity and metabolic diseases, these have been relatively ineffective for a portion of the population. This applies, particularly the individuals with well-established severe obesity and metabolic diseases. It is now recognized that the surgical option can represent for these individuals, an important one that for most of the time will result in a substantial mass loss and a recurring resolution of comorbidities.
The bariatric surgery team from the Institute has a long scientific research tradition to document the effects of weight loss surgical approaches. Particularly the biliopancreatic diversion with duodenal switch, a surgical technique perfected at the Institute and for which the team from the Research Centre developed an internationally recognized expertise. Surgical practices as well as the work on bariatric surgery are nevertheless ever changing. The number of bariatric procedures performed worldwide has not only quickly increased over the last 15 years, but the type of intervention preferred by surgeons and their patients also changed a lot. The parietal gastrectomy now outnumbered the Roux-En-Y gastric bypass in many parts of the world. In addition, the work on the various surgical approaches rose, bringing discoveries that refined our understanding of mechanisms underlying the response related to these procedures. Certain mechanisms are dependent on weight loss and others don’t. However, a lot of work still needs to be carried out in order to identify the determinants of the response to surgery and the means to choose the best approach for each patient.
The REMISSION study, currently underway at the Institute Research Centre is directly attacking these questions. The acronym REMISSION refers to “Reaching Enduring Metabolic Improvements by Selecting Surgical Interventions in Obese Individuals”. Drs. André Tchernof, Laurent Berthio and Denis Richard are principal investigators of this project which aims to study the determinants of the metabolic recovery following the parietal gastrectomy, the gastric bypass as well as the biliopancreatic diversion with duodenal switch in patients and relevant animal models. The research targets three principal axes: 1) the metabolism, 2) the intestinal microbiota, and 3) the relationship between the gut and brain. It is based upon structural hubs that will provide clinical data, biological specimen and animal models. The team involved in this collaborative project includes several researchers from Canada working in three provinces and eight universities or research centres as well as collaborators in the United States and Europe. The work carried out in bariatric surgery at the Institute Research Centre has a significant influence on the medical practice in this field. On the one hand, it provides health care to a population that badly needs it, but it also increases on the other our understanding of the phenomena causing the weight loss and the metabolic healing following the surgery.
Photo: Laurent Biertho, M.D. et André Tchernof, Ph. D.