Obesity is an increasing global health problem associated with several comorbidities and a high risk of mortality. A wide spectrum of interventions has been proposed for weight management in clinical settings, but most are effective only in the short term, since it is common for patients with obesity to gradually regain the weight lost. This unfavourable outcome continues to stimulate researchers to search for an effective long-lasting treatment for obesity.

Mesenchymal stem cells (MSCs) are known for the capacity to self-renew and differentiate into multiple lineages and are widely regarded as powerful candidates for a number of therapeutic applications, such as tissue repair and immune-based disorders. MSCs have also recently received increasing attention as a potential novel therapeutic option for the treatment of obesity because they are a major source of adipocyte generation.

In this view, a group of investigators from the Faculty of Heath Sciences at Beirut Arab University (BAU, Beirut, Lebanon) and their colleagues from the Department of Eating and Weight Disorders from Villa Garda Hospital in Garda, Italy conducted a systematic review, with the aim to summarize findings regarding the effect of Adipose-Derived Mesenchymal Stem Cells (AD-MSCs) on obesity and related comorbidities from the animal model in vivo, in order to establish their viability to justify their use in clinical trials for a human therapy.

Of the 578 articles retrieved, seven studies, met the inclusion criteria, and showed a strong evidence on the positive effect of AD-MSCs in obesity treatment in terms of body weight, glucose metabolism homeostasis, lipid profiles, non-alcoholic fatty liver disease and systemic inflammation.

The principle investigator in this study, Dr Marwan El Ghoch MD, comments..."despite the progress that has been made over the past decade in the development of MSC- based products for the treatment of different diseases in humans, such as degenerative arthritis, post-acute myocardial infarction, and Graft versus Host Disease in clinical settings, surprisingly no human studies have been conducted on the use of MSCs in obesity."

He adds, "our systematic review clearly evidence that the beneficial effects of AD-MSCs transplantation on obesity and related diseases are well documented in animal models".

However, El Ghoch underlines that "these finding should be interpreted with caution before jumping to conclusions. First of all, studies in animals do not predict with sufficient certainty what will happen in humans. In fact around 30 % of animal studies progress to the level of human randomized trials, and only 10 % of the interventions are subsequently approved for use in patients. Second, we should keep in mind that obesity is multi-factor disease that involves in its maintenance not only biological factors but also cognitive, behavioural and environmental factors. Last but not least, it is noteworthy to mention that in the absence of human studies on our topic, we were unable to ascertain the clinical utility and safety of AD-MSCs for patients with obesity".

Dr El Ghoch concludes that despite the promising beneficial effects of AD-MSCs transplantation on obesity in terms of weight loss and obesity-related diseases, which appear well documented in animal models, further well-designed studies should be performed in the future to understand the mechanism of action and to overcome some methodological limitations, such as sample size and the risk of bias evidenced in in our systematic review, before going forward to assess AD-MSCs transplantation as a potential strategy for obesity management in humans.

Saleh F, Itani L, Calugi S, Dalle Grave R, El Ghoch M.
Adipose-Derived Mesenchymal Stem Cells in the Treatment of Obesity: A Systematic Review of longitudinal studides on Preclinical Evidence.
Current Stem Cell Research & Therapy. doi: 10.2174/1574888X13666180515160008.