Metabolic Brain Disease

, Volume 34, Issue 5, pp 1467–1472 | Cite as

The effect of hyperglycinemic treatment in captive-bred Vervet monkeys (Chlorocebus aethiops)

  • Zandisiwe E. MagwebuEmail author
  • Mikateko Mazinu
  • Sahar Abdul-Rasool
  • Chesa G. Chauke
Original Article


Nonketotic hyperglycinemia (NKH) is a neuro-metabolic disorder caused by a deficiency in the glycine cleavage system (GCS) and glycine transporter 1 (GlyT1). A case of atypical late onset of NKH has been reported in a colony of captive-bred Vervet monkeys. The purpose of this study was to evaluate the effect of sodium benzoate and dextromethorphan in reducing glycine levels in hyperglycinemic monkeys. Twelve captive-bred Vervet monkeys were assigned into three groups consisting of four animals (control, valproate induced and cataract with spontaneous hyperglycinemia). Valproate was used to elevate glycine levels and the induced group was then treated with sodium benzoate and dextromethorphan together with group three to normalise glycine levels in cerebrospinal fluid (CSF) and plasma. Valproate induction elicited changes in phosphate, alkaline phosphatase and platelet count, however, no significant changes in the glycine levels were observed, and this might be due to the individual variability within the group. The treatment intervention was only obtained in the spontaneous group whereby the glycine levels were normalised in CSF and plasma. Therefore, it can be concluded that sodium benzoate and dextromethorphan treatment was effective and beneficial to the hyperglycinemic group.


Dextromethorphan Glycine Sodium benzoate Spontaneous hyperglycinemia Valproate and Vervet monkey 



The authors express their gratitude to Joritha van Heerden, Timothy Collop and Abraham Davids for their excellent expertise in handling Vervet monkeys. The South African Medical Research Council/ Primate Unit and Delft Animal Centre for financial support.


The authors did not receive any research grant for this study, however, financial support was provided by the Primate Unit and Delft Animal Centre (PUDAC) of the South African Medical Research Council.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This study was approved by the SAMRC Ethics Committee for Research on Animals (ECRA) (Ref.08/13). All procedure performed in study involving animals were in accordance with the ethical standards of the South African National Standard for the Care and Use of Animals for Scientific Purposes (South African Bureau of Standards, SANS 10386, 2008).


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Primate Unit and Delft Animal CentreSouth African Medical Research CouncilTygerbergSouth Africa
  2. 2.Medical Bioscience DepartmentUniversity of the Western CapeBelvilleSouth Africa

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