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Vertebrate reproductive science and technology
RESEARCH ARTICLE

High-fat diet leads to elevated lipid accumulation and endoplasmic reticulum stress in oocytes, causing poor embryo development

Arpitha Rao A * , Aparna Satheesh A * , Guruprasad Nayak A , Pooja Suresh Poojary A , Sandhya Kumari A , Sneha Guruprasad Kalthur B , Srinivas Mutalik C , Satish Kumar Adiga https://orcid.org/0000-0002-2897-4697 A and Guruprasad Kalthur https://orcid.org/0000-0002-4554-2917 A D
+ Author Affiliations
- Author Affiliations

A Department of Clinical Embryology, Kasturba Medical College Manipal, Manipal Academy of Higher Education, Manipal 576 104, Karnataka State, India.

B Department of Anatomy, Kasturba Medical College Manipal, Manipal Academy of Higher Education, Manipal 576 104, Karnataka State, India.

C Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal 576 104, Karnataka State, India.

D Corresponding author. Email: guru.kalthur@manipal.edu

Reproduction, Fertility and Development 32(14) 1169-1179 https://doi.org/10.1071/RD20112
Submitted: 30 April 2020  Accepted: 28 July 2020   Published: 1 October 2020

Abstract

The present study was designed to investigate the effect of diet-induced obesity on endoplasmic reticulum (ER) stress in oocytes. Swiss albino mice (3 weeks old) were fed with a high-fat diet (HFD) for 8 weeks. Oocytes were assessed for lipid droplet accumulation, oxidative stress, ER stress and their developmental potential in vitro. High lipid accumulation (P < 0.01) and elevated intracellular levels of reactive oxygen species were observed in both germinal vesicle and MII oocytes of HFD-fed mice (P < 0.05 and P < 0.01 respectively compared with control). Further, expression of the ER stress markers X-box binding protein 1 (XBP1), glucose-regulated protein 78 (GRP78), activating transcription factor 4 (ATF4) and activating transcription factor 6 (ATF6) was significantly (P < 0.001) higher in oocytes of the HFD than control group. Oocytes from HFD-fed mice exhibited poor fertilisation and blastocyst rates, a decrease in total cell number and high levels of DNA damage (P < 0.01) compared with controls. In conclusion, diet-induced obesity resulted in elevated lipid levels and higher oxidative and ER stress in oocytes, which contributed to the compromised developmental potential of embryos.

Graphical Abstract Image

Additional keyword: reproduction.


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