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bioRxiv · 10.1101/317024

PID1 alters antilipolytic action of insulin and increases lipolysis via Inhibited the activation of AKT/PKA Pathway

yin, c. y.·jin, y.·liu, y. s.·wang, l.·xiao, y.
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Abstract

PurposeThe aim was to investigate the mechanism for impaired control of lipolysis in obesity by investigating the effect of PID1 on insulin-induced activation of AKT/PKA/HSL pathway and lipolysis.\n\nMethodsFirst, PID1 expression was detected in adipose tissue and blood insulin and glycerol levels were measured in high-fat diet-induced obese rats. Next, we examined the effect of different concentrations of insulin on lipolysis and AKT/PKA/HSL pathway in 3T3-L1cells. We also investigated the role of PID1 in regulating AKT/PKA/HSL cascade and lipolysis after insulin treatment and lipofectamine over-expression.\n\nResultsPID1 expression is increased in adipose tissue from HFD rat and positive correlation with insulin levels and lipolysis. In 3T3-L1 adipocytes, we found that antilipolytic effect of insulin is mediated by AKT and AKT activated by insulin can results in phosphorylation of PKA and HSL and suppresses glycerol release. However, over-expression of PID1 counteracts insulin action as indicated by glycerol releaseand reduced level of Akt phosphorylation in accordance with a decrease in the activity of insulin-dependent PKA/HSLsignaling cascade.\n\nConclusionsAll together, these data showed that activation of PID1 in adipose tissue increases lipolysis by altering the antilipolytic action of insulin. This suggests that PID1 may constitute a new strategy to ameliorate adipocyte lipolysis and hence to improve insulin sensitivity.

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yin, c. y., jin, y., liu, y. s., wang, l., xiao, y.. 2018-05-08. PID1 alters antilipolytic action of insulin and increases lipolysis via Inhibited the activation of AKT/PKA Pathway. https://doi.org/10.1101/317024

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