RT Journal Article SR Electronic T1 Hyperinsulinemia due to altered insulin secretion contributes to insulin resistance in chronic intermittent hypoxia independently of obesity JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP OA4935 DO 10.1183/13993003.congress-2019.OA4935 VO 54 IS suppl 63 A1 Sacramento, Joana F. A1 Melo, Bernardete F. A1 Olea, Elena A1 Obeso, Ana A1 Rocher, Asuncion A1 Rodrigues, Tiago A1 Prieto-Lloret, Jesus A1 Yubero, Sara A1 Monteiro, Emilia C. A1 Matafome, Paulo A1 Conde, Silva V. YR 2019 UL http://erj.ersjournals.com/content/54/suppl_63/OA4935.abstract AB Clinical studies have demonstrated a link between obstructive sleep apnea (OSA) and insulin resistance (IR), however it is not clear which is the main event that determines IR development. We hypothesize that hyperinsulinemia is a main driver of IR in chronic intermittent hypoxia (CIH), that mimics OSA, independently of obesity, adipose tissue hypoxia and severity of CIH.Male Wistar Rats were submitted to 2 CIH protocols: 1) a mild CIH paradigm obtained by 5/6 hypoxic (5%O2) cycles/h, 10.5 h/day during 35 days; and 2) a severe CIH paradigm obtained by 40 s, 5%O2/80 s, air, equivalent to an apnoea–hypopnoea index of 30, 8h/day for 14 days. CIH animals were compared with controls. Fasting glycemia, insulinemia, C-peptide and insulin sensitivity through KITTand HOMA index were measured. Insulin clearance was calculated. Weight and fat mass were assessed. Adipose tissue dysfunction and inflammation were assessed by evaluation of several proteins involved in insulin signaling pathways and hypoxia and inflammation pathways.Mild CIH increased insulin secretion by 214% (CTLmildCIH =1.01±0.21ug/L) while severe CIH increased by 103% (CTLsevereCIH= 1.1±0.04ug/L) with no alterations in fasting glycemia in both CIH protocols. HOMA index increased by 112% in mild CIH and by 108% in severe CIH animals. None of CIH protocols alter weight gain and fat mass deposition. Mild and severe CIH increased IR in adipose tissue, with no changes in HIF1 and 2α expression.We can conclude that both mild and severe CIH protocols induce insulin resistance, which is associated with an increase insulin secretion by the pancreas being independent of obesity and fat mass.FootnotesCite this article as: European Respiratory Journal 2019; 54: Suppl. 63, OA4935.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).