Betatrophin Levels were Increased in Pregnant Women with or without Gestational Diabetes Mellitus and Associated with Beta Cell Function

Abstract Purpose betatrophin has been reported to boost β cell expansion in insulin resistant states. Pregnancy is a well-recognized physiological state of insulin resistance. Betatrophin levels in pregnant women and their relationships with metabolic variables remain to be elucidated. Methods A total of 49 pregnant women and 31 age-matched unpregnant women with normal glucose regulation (UP-NGR) were included. Among these subjects, according to results from 75 g oral glucose tolerance test (OGTT), 22 women were diagnosed as having gestational diabetes mellitus ( GDM ). Results Our study found that pregnant women, regardless of their glucose regulation status, had remarkably higher triglycerides (TG), total cholesterol (TC), fasting insulin (FINS), homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of β-cell function (HOMA-β). However, GDM patients had much lower HOMA-β compared with those of pregnant women with normal glucose regulation (P-NGR). Participants of the P-NGR group had almost 4 times higher levels of betatrophin than those of the UP-NGR group. Although betatrophin levels were lower in the GDM group than those of the P-NGR group, the difference did not reach statistical significance. Spearman correlation analysis showed that betatrophin levels were positively and significantly associated with total cholesterol, triglycerides, highdensity lipoprotein cholesterol (HDL-c), FINS and HOMA-β. However, adjustments of TC, TG and HDL-c eliminated the association between HOMA-β and betatrophin. Conclusions Pregnant women have significantly higher betatrophin levels in comparison to unpregnant women. Betatrophin levels are positively and significantly associated with β cell function and lipid levels. Furthermore, lipids may contribute to the association between betatrophin and β cell function.

摘要：
研究目的：有研究报道，促β细胞素（betatrophin）可在胰岛素抵抗状态下促进β细胞增殖。妊娠是公认的胰岛素抵抗生理状态，而妊娠期女性体内的促β细胞素水平及其与代谢指标的关联仍有待阐明。
研究方法：本研究共纳入49名妊娠女性，以及31名年龄匹配、糖代谢正常的非妊娠女性（UP-NGR）。根据75g口服葡萄糖耐量试验（OGTT）结果，其中22名女性被诊断为妊娠期糖尿病（GDM）。
研究结果：本研究发现，无论糖代谢状态如何，妊娠女性的甘油三酯（TG）、总胆固醇（TC）、空腹胰岛素（FINS）、胰岛素抵抗稳态模型评估指数（HOMA-IR）及β细胞功能稳态模型评估指数（HOMA-β）均显著升高。但与妊娠糖代谢正常女性（P-NGR）相比，GDM患者的HOMA-β水平显著更低。P-NGR组女性的促β细胞素水平约为UP-NGR组的4倍。尽管GDM组的促β细胞素水平低于P-NGR组，但差异未达到统计学显著性。Spearman相关分析显示，促β细胞素水平与总胆固醇、甘油三酯、高密度脂蛋白胆固醇（HDL-c）、空腹胰岛素及HOMA-β呈显著正相关。在校正TC、TG及HDL-c后，HOMA-β与促β细胞素的关联消失。
研究结论：与非妊娠女性相比，妊娠女性的促β细胞素水平显著升高。促β细胞素水平与β细胞功能及血脂水平呈显著正相关。此外，血脂可能参与介导促β细胞素与β细胞功能之间的关联。