The Effect of Averrhoa carambola (Star Fruit) Aqueous Fruit Extract on the Hippocampal Astrocyte Expression Following Diazepam-Induced Neurotoxicity in Wistar Rats


  • Sadeyeng E. Anani Department of Anatomical sciences, faculty of Basic Medical Sciences, University of Calabar, Nigeria
  • Eru M. Eru Department of Anatomical sciences, faculty of Basic Medical Sciences, University of Calabar, Nigeria
  • Deborah E. Okon Department of Anatomical sciences, faculty of Basic Medical Sciences, University of Calabar, Nigeria
  • Kelechi C. Uruakpa Department of Anatomical sciences, faculty of Basic Medical Sciences, University of Calabar, Nigeria
  • Theophilus I. Ugbem Department of Histo-pathology, University of Calabar Teaching Hospital, Calabar, Nigeria
  • Anozeng O. Igiri Department of Anatomical sciences, faculty of Basic Medical Sciences, University of Calabar, Nigeria


Glial Fibrillary Acidic Protein, Hippocampus, Diazepam, Averrhoa carambola


Neurotoxicity is caused by physical, chemical or biological agents which exert an effect on the structure or function of the nervous system. Drugs of abuse, including Diazepam are common, and have been known to cause neurotoxicity.The hippocampus which plays a critical role in the formation, organization and storage of memory is the most affected structure in several neurological disorders. Averrhoa carambola is a plant native to tropical South-East Asia and known for its health protective properties. The study investigated the effect of aqueous Averrhoa carambola fruit extract on hippocampal astrocyte expression following Diazepam-induced neurotoxicity in Wistar rats. Twentyfive female rats were divided into five (5) groups. Group A served as the negative control group, while group B served as positive control and received Diazepam (25mg/kg body weight) alone. Groups C, D and E were given Diazepam (25mg/kg BW) + 1000mgAverrhoa carambola extract, Diazepam (25mg/kg BW) + 600mg Averrhoa carambola extract and Diazepam (25mg/kg BW) + 300mg Averrhoa carambola extract respectively for 30 days. Glial fibrillary acidic protein (GFAP) immunoreactivity in the hippocampus displayed immunonegativity for group A rats, while a high level of GFAP-reactive astrocyte expression was observed in groups B, D and E. An increase in the number of astrocytes (hyperplasia) as well as reduced GFAP-reactive astrocyte expression was observed in group C which may be indicative of neuroprotective effects of the aqueous fruit extract. Averrhoa carambola aqueous fruit extract can therefore ameliorate Diazepam-induced toxicity of the hippocampus in Wistar rats, and the effects were dose-dependent.


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How to Cite

Anani, S. E., Eru, E. M., Okon, D. E., Uruakpa, K. C., Ugbem, T. I., & Igiri, A. O. (2020). The Effect of Averrhoa carambola (Star Fruit) Aqueous Fruit Extract on the Hippocampal Astrocyte Expression Following Diazepam-Induced Neurotoxicity in Wistar Rats: Tropical Journal of Natural Product Research (TJNPR), 4(12), 1174–1177. Retrieved from

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