Neurotoxic and neuromotor effects of cyanate, an oxidative byproduct of cyanide from linamarin in cassava: A systematic review
Background Linamarin-induced neurotoxicity manifests as either polyneuropathy, ataxia, and sensorineural deafness or as isolated symmetric spastic paraparesis of bilateral limbs, which are frequently observed in populations subsisting on a monotonous cassava-based diet. Attributable to the potential protein deficiency resulting from this dietary regimen, cyanide derived from linamarin may undergo oxidation to cyanate, a neurotoxin known to carbamoylate proteins and induce oxidative stress.
Aim: To synthesize preclinical and clinical evidence concerning cyanate-induced neurotoxicity, thereby identifying the predominant neurological adverse events following sodium cyanate exposure.
Methods: This study employed a systematic review methodology, utilizing four electronic databases (PubMed, Scopus, Cochrane Library, Google Scholar) to identify for publications on the neurotoxicity of cyanate from 1936 to 2024. A total of 1,089 articles were screened. Studies investigating non-neurotoxic effects and those lacking full-text availability were excluded, resulting in the selection of 10 for quality assessment and review. Preclinical studies were evaluated using the SYRCLE risk-of-bias tool, while non-randomized clinical studies were assessed using the Newcastle-Ottawa scale.
Results: The majority of studies were preclinical. One case-control study investigated the association between spastic paraparesis and protein carbamoylation. Rodents exposed to high-dose sodium cyanate (NaOCN) developed hindlimb spastic weakness or paralysis in 42.86% of animal studies, and ataxia, dysmetria, and cognitive impairment in 14.26%. Peptide carbamoylation was reported in 42.86%, while one study (14.26%) reported demyelination of the spinal cord. The sole case-control study reported a statistically significant (p = 0.01) association between severe konzo and carbamoylation of serum peptides.
Conclusion: Sodium cyanate administration at doses ranging from 60 to 200 mg/kg resulted in hindlimb weakness or spastic paralysis in rodents and spinal cord demyelination in primates, findings strikingly identical to the spastic paraparesis observed in konzo. Further investigations are required to determine the association between cyanate exposure and the development of spastic paraparesis resulting from monotonous cassava consumption.
Keywords
How to Cite
Adamolekun B. (2010). Thiamine deficiency and the etiology of tropical ataxic neuropathy. International health, 2(1), 17–21. https://doi.org/10.1016/j.inhe.2009.12.004
Alter, B.P., Kan, Y.W., & Nathan, D.G. (1974). Alter, B. P., Kan, Y. W., & Nathan, D. G. (1974). Toxic effects of high-dose cyanate administration in rodents. Blood, 43(1), 69–77. https://doi.org/10.1182/blood.v43.1.69.69
Baguma, M., Nzabara, F., Maheshe Balemba, G., Malembaka, E. B., Migabo, C., Mudumbi, G., Bito, V., Cliff, J., Rigo, J. M., & Chabwine, J. N. (2021). Konzo risk factors, determinants and etiopathogenesis: What is new? A systematic review. Neurotoxicology, 85, 54–67. https://doi.org/10.1016/j.neuro.2021.05.001
Boivin, M. J., Okitundu, D., Makila-Mabe, B., Sombo, M. T., Mumba, D., Sikorskii, A., Mayambu, B., & Tshala-Katumbay, D. (2017). Cognitive and motor performance in Congolese children with konzo during 4 years of follow-up: a longitudinal analysis. The Lancet. Global health, 5(9), e936–e947. https://doi.org/10.1016/S2214-109X(17)30267-X
Cai, H., & Li, G. (2020). Efficacy of alginate-and chitosan-based scaffolds on the healing of diabetic skin wounds in animal experimental models and cell studies: A systematic review. Wound Repair and Regeneration: The International Journal of Tissue Repair and Regeneration, 28(6), 751–771. https://doi.org/10.1111/wrr.12857
Charache, S., Duffy, T. P., Jander, N., Scott, J. C., Bedine, M., & Morrell, R. (1975). Toxic-therapeutic ratio of sodium cyanate. Archives of Internal Medicine, 135(8), 1043–1047.
Chen, C., Kashala-Abotnes, E., Banea Mayambu, J. P., Mumba Ngoyi, D., Tshala-Katumbay, D., Mukeba, D., Kunyu, M., Boivin, M. J., & Wu, F. (2021). Cost-effectiveness of a wetting method intervention to reduce cassava cyanide-related cognitive impairment in children. Nature Food, 2(7), 469–472. https://doi.org/10.1038/s43016-021-00321-w
Chijioke, U., Madu, T., Okoye, B., Ogunka, A. P., Ejechi, M., Ofoeze, M., Ogbete, C., Njoku, D., Ewuziem, J., Kalu, C., Onyemauwa, N., Ukeje, B., Achonwa, O., Forsythe, L., Fliedel, G., & Egesi, C. (2021). Quality attributes of fufu in South-East Nigeria: guide for cassava breeders. International Journal of Food Science & Technology, 56(3), 1247–1257. https://doi.org/10.1111/ijfs.14875
Choi, H.-J. & Lee, S.-H. (2017). Cyanate Induces Apoptosis of Rat Glioma Cell Line. Journal of Life Science, 27(3), 267–274. http://dx.doi.org/10.5352/JLS.2017.27.3.267
Delporte, C., Zouaoui Boudjeltia, K., Furtmüller, P. G., Maki, R. A., Dieu, M., Noyon, C., Soudi, M., Dufour, D., Coremans, C., Nuyens, V., Reye, F., Rousseau, A., Raes, M., Moguilevsky, N., Vanhaeverbeek, M., Ducobu, J., Nève, J., Robaye, B., Vanhamme, L., Reynolds, W. F., … Van Antwerpen, P. (2018). Myeloperoxidase-catalyzed oxidation of cyanide to cyanate: A potential carbamylation route involved in the formation of atherosclerotic plaques? The Journal of Biological Chemistry, 293(17), 6374–6386. https://doi.org/10.1074/jbc.M117.801076
Similar Articles
You may also start an advanced similarity search for this article.

NAJFNR is licensed under