Abstract:

[Abstract]   Objective   To study the effect of different degrees of intermittent hypoxia (IH) on inflammatory cytokines
and adipokines in3T3-L1adipocytes.  Methods   An intermittent hypoxia/reoxygenation (IH/ROX) from obstructive sleep apnea (OSA) adipocyte model was established.3T3-L1adipocytes were divided into five groups, three IH groups (5% O2,7.5% O2 and10% O2, referred to as IH-1, IH-2and IH-3), sustained hypoxia group (10% O2, CH) and the normal oxygen control group (21%O2, IN). ELISA method was used to detect values of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), leptin and adiponectin in cell supernatant. Western blot analysis was used to detect levels of hypoxia-inducible factor-1α(HIF-1α) and glucose transporter-1(Glut-1). RT-PCR assay was used to analyze HIF-1α, Glut-1, TNF-α, IL-6, leptin and adiponectin mRNA expression levels in adipocytes.   Results   The expression levels of TNF-α, IL-6and leptin  were significantly higher in IH and CH groups than those of IN group (P＜0.05). The expression levels of TNF-α, IL-6and leptin protein and leptin mRNA were significantly higher in IH-1group than those of IH-2and IH-3groups (P＜0.05). The adiponectin and its mRNA levels were significantly lower in IH and CH groups than those of IN group (P＜0.05). The adiponectin level was significantly lower in IH-1group than that of IH-2and IH-3groups (P＜0.05).  Conclusion   These results demonstrate that IH is related to the extensive changes in the expression and release of inflammation-related adipokines in cultured adipocytes. IH from OSA may underlie the development of the inflammatory response in adipocytes, which is involved in insulin resistance in patients with OSA.

Key words: intermittent hypoxia, Insulin Resistence, tumor necrosis factor-α, interleukin-6, hypoxia-induciblefactor1, alpha subunit, glucose transporter type 1, 瘦素