TY - JOUR T1 - Plasma MOTS-c levels are associated with insulin sensitivity in lean but not in obese individuals JF - Journal of Investigative Medicine JO - J Investig Med SP - 1019 LP - 1022 DO - 10.1136/jim-2017-000681 VL - 66 IS - 6 AU - Luis Rodrigo Cataldo AU - Rodrigo Fernández-Verdejo AU - José Luis Santos AU - Jose Eduardo Galgani Y1 - 2018/08/01 UR - http://hw-f5-jim.highwire.org/content/66/6/1019.abstract N2 - Mitochondrial open reading frame of the 12S rRNA-c (MOTS-c) is a mitochondrial-derived peptide that attenuates weight gain and hyperinsulinemia when administered to high fat-fed mice. MOTS-c is therefore a potential regulator of metabolic homeostasis under conditions of high-energy supply. However, the effect of insulin resistance and obesity on plasma MOTS-c concentration in humans is unknown. To gain insight into MOTS-c regulation, we measured plasma MOTS-c concentration and analyzed its relationship with insulin sensitivity surrogates, in lean and obese humans (n=10 per group). Obese individuals had impaired insulin sensitivity as indicated by low Matsuda and high Homeostatic Model Assessment (HOMA) indexes. Although plasma MOTS-c concentration was similar in lean and obese individuals (0.48±0.16 and 0.52±0.15 ng/mL; p=0.60), it was correlated with HOMA (r=0.53; p<0.05) and Matsuda index (r=−0.46; p<0.05). Notably, when the groups were analyzed separately, the associations remained only in lean individuals. We conclude that plasma MOTS-c concentration is unaltered in human obesity. However, MOTS-c associates positively with insulin resistance mostly in lean individuals, indicating that plasma MOTS-c concentration depends on the metabolic status in this population. Such dependence seems altered when obesity settles. The implications of plasma MOTS-c for human metabolic homeostasis deserve future examination. ER -