Prenatal kolanut exposure suppresses hippocampal dentate gyrus neurogenesis in adolescent and young adult rats

Kolanut, a social delicacy for men and women, including pregnant women, in West African countries, and in sub-Saharan African continent contains caffeine, theobromide and tannins. This study investigated the possible adverse effects of kolanut following prenatal exposure on hippocampal neurogenesis in adolescent rats. 12 Sprague Dawley pregnant rats were exposed to 400 mg/kg kolanut consumption daily from first day until parturition. 24 pups were grouped into three groups of 8 pups into postnatal day (PND) 21, 56 and 70, and each sub grouped into control and treated groups. Six brain sections per animal were processed for Nissl, DCX and Ki-67 immunohistochemical staining, malonaldehyde (MDA) and brain derived neurotropic factor (BDNF) using ELISA technique.

Histomorphology examination on Nissl stain sections showed gestational significantly reducing mean area, mean diameter and mean neuronal density at PND 21 and 56 and significantly inhibited DCX immunoreaction and expression in migrating neurons in subgranular zone of dentate gyrus at PND 21, 56 and 70 in comparison to control groups respectively. At PND 21 and 70, gestational kolanut treatment suppressed cumulative neurogenesis by inhibiting expression of Ki-67 protein in subgranular zone of dentate gyrus but significantly increased hippocampal expression of BDNF protein at PND 56 and 70 and hippocampal MDA concentration at PND 21, 56 and 70. Prenatal gestational kolanut consumption adversely decreased the process of neurogenesis and inhibited normal neuronal maturation and differentiating processes and provoked decreased generation of neural progenitor cells in the hippocampus, suggesting caution/moderation in the use of kolanut by pregnant women to avert possible postnatal cognitive defects in their children later in life.

This research was supported by the Consortium for Advanced Research Training in Africa (CARTA). CARTA is jointly led by the African Population and Health Research Centre and the University of the Witwatersrand and funded by the Carnegie Corporation of New York (Grant No. G-21-58722 and G-PS-23-60922), Sida (Grant No: 16604), Norwegian Agency for Development Cooperation (Norad) (Grant No: QZA-21/0162), Oak Foundation (Grant No.

OFIL-24-091) and the Science for Africa Foundation to the Developing Excellence in Leadership, Training and Science in Africa (DELTAS Africa) programme (Del-22-006) with support from Wellcome and the UK Foreign, Commonwealth & Development Office and is part of the EDCPT2 programme supported by the European Union. The statements made and views expressed are solely the responsibility of the Author." Missouri School of Dentistry and Oral Health, A. Still University, Kirksville, MO, USA School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa Foluso A.

Ihunwo College of Osteopathic Medicine, A. Still University , Kirksville, MO, USA Department of Human Anatomy and Physiology, University of Johannesburg, Doornfontein Campus, Johannesburg, South Africa The authors have no relevant financial or non-financial interests to disclose. This study was performed in line with the principles and guidelines of ARRIVE.

Approval was granted by the Animal Research Ethics Committee of University of the Witwatersrand, Johannesburg, South Africa (2020/06/02/C). Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.