Impact of Weight Loss on the Human Sperm Epitranscriptome

Increasing evidence suggests that non-communicable diseases such as in particular obesity and its associated metabolic diseases are inherited from parents to children throughout several generations by epigenetic mechanisms. Thus, this environmental stress would induce epigenetic modification in the germ line that once transmitted and maintained in the progeny would induce the development of the parental pathologies. Considering the increasing prevalence of these pathologies worldwide, we urgently need to understand this process in human. Based on published and unpublished data demonstrating that sperm RNAs are vectors of epigenetic inheritance of obesity mouse model, the investigative team hypothesizes that epitranscriptome of obese men play a central role in the paternal epigenetic inheritance of obesity and its associated metabolic diseases as epigenetic vectors in this process. To validate this hypothesis, the investigative team will use sperm from non-obese and obese men taken before and after surgery weight loss. Thanks to these cohorts, they propose to: (i) compare the epitranscriptome profiles of non-obese and obese men to identify the RNAs molecules which will be either qualitatively or quantitatively epigenetically modulated by obesity; (ii) compare the epitranscriptome profiles of obese men before and after surgery-weight loss to assess the reversibility of the newly acquired RNA modifications. Giving some answers to this central question will provide not only some clues about the molecular mechanisms involved in this process, elements which might be crucial to stop the spread of this disorder, but will also allow the identification of obese-susceptibility loci which expression may be modulate by environmental factors and consequently able to transmit the disease.