Plain language summary
Obesity is a public health concern as it has been linked to cardiovascular diseases, type 2 diabetes and metabolic syndrome. The aim of this study was to identify and analyse expression profiles of individuals clustered by cellular metabolism centring on metabolic flexibility. This study clustered gene expression samples from a weight loss study (Yoyo study’ - Clinical Trial ID: NCT01559415) into two clusters, based on 291 genes associated with cellular metabolic fexibility. The study covers two diets: a low-calorie diet (LCD) and a very low-calorie diet (VLCD). All the participants of the study were Caucasian with a BMI between 28kg/m2 and 35 kg/m2, aged between 32 and 67 years old. Findings showed that the majority of the individuals had their metabolism associated genes downregulated after weight loss and weight maintenance, but also had an upregulation of immune system associated genes. Furthermore, individuals who had changed their metabolic profiles in response to caloric restriction had a significant retention of lost weight compared to individuals which had not changed their cluster membership. Authors conclude that their findings indicate possible cross-talk between cellular metabolism and inflammation.
Abstract
Obesity is a global epidemic, contributing significantly to chronic non-communicable diseases, such as type 2 diabetes mellitus, cardiovascular diseases and metabolic syndrome. Metabolic flexibility, the ability of organisms to switch between metabolic substrates, is found to be impaired in obesity, possibly contributing to the development of chronic illnesses. Several studies have shown the improvement of metabolic flexibility after weight loss. In this study, we have mapped the cellular metabolism of the adipose tissue from a weight loss study to stratify the cellular metabolic processes and metabolic flexibility during weight loss. We have found that for a majority of the individuals, cellular metabolism was downregulated during weight loss, with gene expression of all major cellular metabolic processes (such as glycolysis, fatty acid β-oxidation etc.) being lowered during weight loss and weight maintenance. Parallel to this, the gene expression of immune system related processes involving interferons and interleukins increased. Previously, studies have indicated both negative and positive effects of post-weight loss inflammation in the adipose tissue with regards to weight loss or obesity and its co-morbidities; however, mechanistic links need to be constructed in order to determine the effects further. Our study contributes towards this goal by mapping the changes in gene expression across the weight loss study and indicates possible cross-talk between cellular metabolism and inflammation.
Methodological quality
Jadad score
:
Not applicable
Allocation concealment
:
Not applicable
