Dept. of Medical, Surgical and Health Sciences, University of Trieste, Italy.
Dept. of Medical, Surgical and Health Sciences, University of Trieste, Italy.
Clin Nutr. 2017 Jun;36(3):775-781. doi: 10.1016/j.clnu.2016.05.017. Epub 2016 Jun 6.
BACKGROUND & AIMS: Ghrelin is a gastric orexigenic hormone whose activating acylation plays a relevant role in the regulation of energy balance. Nutritional modulators of ghrelin acylation and plasma acylated ghrelin (AG) concentration remain however largely undefined. We aimed at investigating whether circulating free fatty acids (FFA) contribute to regulate plasma AG and its ratio (AG/TG) to total hormone (TG).
Plasma FFA, TG, AG and AG/TG were measured in a primary outpatient care setting in a community-based population cohort of 850 individuals (age 54 ± 10 years, M/F: 408/442) from the North-East Italy MoMa study. 150-min intravenous lipid infusions in rodents (10% lipids, 600 μl/h) were used to investigate the potential causal role of FFA in the regulation of plasma ghrelin profile.
Plasma FFA were associated positively with AG and AG/TG while negatively with TG (P < 0.01). Associations between FFA, AG and AG/TG remained statistically significant (P < 0.02) in multiple regression analysis including HOMA insulin resistance and metabolic confounders, and both AG and AG/TG but not TG increased through plasma FFA quartiles (P < 0.01). Consistent with these findings, intravenous lipid infusion with plasma FFA elevation caused elevations of AG and AG/TG (P < 0.05) with no TG modifications.
The current findings demonstrate a novel role for circulating FFA availability to up-regulate plasma AG, which could involve FFA-induced stimulation of ghrelin acylation.
Ghrelin 是一种胃促食欲激素,其激活酰化在调节能量平衡中起重要作用。然而,ghrelin 酰化和血浆酰化 ghrelin(AG)浓度的营养调节剂在很大程度上仍未得到定义。我们旨在研究循环游离脂肪酸(FFA)是否有助于调节血浆 AG 及其与总激素(TG)的比值(AG/TG)。
在意大利东北部的 MoMa 研究中,我们在一个基于社区的 850 人个体(年龄 54±10 岁,M/F:408/442)的初级门诊护理环境中测量了血浆 FFA、TG、AG 和 AG/TG。在啮齿动物中进行 150 分钟的静脉内脂质输注(10%脂质,600μl/h),以研究 FFA 在调节血浆 ghrelin 谱中的潜在因果作用。
血浆 FFA 与 AG 和 AG/TG 呈正相关,与 TG 呈负相关(P<0.01)。在包括 HOMA 胰岛素抵抗和代谢混杂因素的多元回归分析中,FFA 与 AG 和 AG/TG 之间的相关性仍然具有统计学意义(P<0.02),并且在包括 HOMA 胰岛素抵抗和代谢混杂因素的多元回归分析中,FFA 与 AG 和 AG/TG 之间的相关性仍然具有统计学意义(P<0.02),并且在包括 HOMA 胰岛素抵抗和代谢混杂因素的多元回归分析中,FFA 与 AG 和 AG/TG 之间的相关性仍然具有统计学意义(P<0.02),并且在包括 HOMA 胰岛素抵抗和代谢混杂因素的多元回归分析中,FFA 与 AG 和 AG/TG 之间的相关性仍然具有统计学意义(P<0.02),并且在包括 HOMA 胰岛素抵抗和代谢混杂因素的多元回归分析中,FFA 与 AG 和 AG/TG 之间的相关性仍然具有统计学意义(P<0.02)。此外,AG 和 AG/TG 但不是 TG 通过血浆 FFA 四分位数增加(P<0.01)。与这些发现一致的是,静脉内脂质输注导致血浆 FFA 升高,引起 AG 和 AG/TG 升高(P<0.05),而 TG 没有变化。
目前的研究结果表明,循环 FFA 的可用性在调节血浆 AG 方面具有新的作用,这可能涉及 FFA 诱导的 ghrelin 酰化刺激。