Nano-graphene oxide particles induce inheritable anomalies through altered gene expressions involved in oocyte maturation

Abstract

The inheritable impact of exposure to graphene oxide nanoparticles (GO NPs) on vertebrate germline during critical windows of gamete development remain undetermined to date. Here, we analyzed the transgenerational effects of exposure to nano-graphene oxide particles (nGO) synthesized in house with lateral dimensions 300–600 nm and surface charge of −36.8 mV on different developmental stages of germ cells (GCs): (1) during GCs undergoing early development and differentiation, and (2) during GCs undergoing gametogenesis and maturation in adulthood. Biocompatibility analyses in Japanese medaka embryos showed lethality above 1 µg/ml and also an aberrant increase in germ cell count of both males and females at doses below the lethal dose. However, no lethality or anomalies were evident in adults up to 45 µg/ml. Long term exposure of embryos and adults for 21 days resulted in reduced fecundity. This effect was transmitted to subsequent generations, F1 and F2. Importantly, the inheritable effects of nGO in adults were pronounced at a high dose of 10 µg/ml, while 1 µg/ml showed no impact on the germline indicating lower doses used in this study to be safe. Further, expressions of selected genes that adversely affected oocyte maturation were enhanced in F1 and F2 individuals. Interestingly, the inheritance patterns differed corresponding to the stage at which the fish received the exposure.

Keywords:

• Graphene oxide nanoparticles
• nanotoxicity
• germ cell development
• transgenerational effects
• Japanese medaka

Acknowledgments

The authors acknowldege Department of Science and Technology, Government of India for providing financial support for the good conduct of this work. We also acknowledge National Bioresource Project (NBRP), Japan, for providing the medaka strain and Ms. Radha Sajeevan for taking care of the medaka fish core facility as well as providingassistance to the research work.

Disclosure statement

The authors declare that no conflicting interests exist in association with the contents of this article and all authors have approved the manuscript. This work was not previously published and is also not under consideration for publication elsewhere.

Data availability statement

The corresponding author declare to share the data of this work on reasonable request.

Additional information

Funding

This work was supported through Nanomission research grant (SR/NM/NS-1070/2012(G)) to Bindhu Paul-Prasanth and Women Scientist Scheme–A research grant (SR/WOS-A/LS-60/2017(G)) to Sreelakshmi Krishnakumar.