INS and Insulin resistance: Notably, in vivo studies on insulin resistant obese patients showed increased ceramides levels in muscle biopsies (Adams et al., 2004; Straczkowski et al., 2007) and newly discovered evidence has identified C16:0-ceramide as the principal mediator of obesity-related insulin resistance (Hla and Kolesnick, 2014; Raichur et al., 2014; Turpin et al., 2014).