Oral administration of l-carnitine improves the clinical outcome of fertility in patients with IVF treatment

Abstract

Age-dependent decline of mitochondrial function has been proposed to be a main cause of decline of embryo quality. Then, l-carnitine plays important roles in reducing the membranous toxicity of free-fatty acids by forming acyl-carnitine and promoting β-oxidation, preventing cell damage. Recent research revealed that l-carnitine played important roles in vitro in oocyte growth, oocyte maturation and embryo development. However, such beneficial effects of l-carnitine in vivo have yet to be verified. The effect of oral l-carnitine supplementation on embryo quality and implantation potential was examined. A total of 214 patients were included in this study. They all previously received in vitro fertilization-embryo transfer (IVF-ET) and failed to conceive. Then they were administered l-carnitine for 82 days on average and underwent IVF-ET again. There were no significant differences in the total number of retrieved oocytes, and their maturation and fertilization rates between before and after l-carnitine administration. The quality of embryos on Days 3 and 5 after insemination was improved following l-carnitine administration (p < .05) in cycles after l-carnitine administration compared with previous cycles. Healthy neonates were born after IVF-ET following l-carnitine administration. Our data suggested that oral administration of l-carnitine to fertility patients improved the developmental competence of their oocytes after insemination.

Chinese abstract

口服左旋肉碱可提高接受IVF治疗的生育期患者的临床结局

摘要

线粒体功能的年龄依赖性下降被认为是导致胚胎质量下降的重要因素之一。左旋肉碱通过形成酰基肉碱和促进β-氧化来防止细胞损伤, 在降低游离脂肪酸的膜毒性方面起着重要作用。近期研究显示, 左旋肉碱在体外对卵母细胞生长, 卵母细胞成熟和胚胎发育过程中发挥着重要作用。然而, 左旋肉碱的这种有益作用在体内是否存在尚未得到证实。口服左旋肉碱补充剂对胚胎质量和种植潜能的影响已经进行检测。本研究共纳入214例患者, 她们之前都接受过体外受精-胚胎移植（IVF-ET）而且均未受孕。患者平均服用82天左旋肉碱后再次接受IVF-ET, 其获卵总数、卵母细胞成熟和受精率在左旋肉碱给药前后无显著差异。与之前的周期相比, 左旋肉碱给药后的周期中, 授精后第3天和第5天的胚胎质量得到提高（p <.05）。接受左旋肉碱给药后的IVF-ET后出生的新生儿身体健康。我们的数据表明, 生育期患者口服左旋肉碱后可以提高其授精后卵母细胞的发育能力。

关键词: 生育治疗, 游离脂肪酸, 线粒体

Keywords:

• Fertility treatment
• free-fatty acids
• mitochondria

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported in part by a grant from the Japan Agency for Medical Research and Development (17gk0110014s0402 to S.H. and Y.M.) and a grant from the Japan Society for the Promotion of Science (17K08144 to S.H.).