Chronic consumption of calabash chalk diet induces depression, cognitive impairment and hepatotoxicity in mice

Background: Calabash chalk (CC) is a geophagic material consumed in many parts of the world for pleasure, as a remedy for hyperemesis gravidarum, sialorrhea, and for foetal bone development. Several potential harmful elements are reported to be present in CC.

Objectives: This study evaluated the effect of CC diet on neurobehavioural indices, brain and liver histomorphological changes in mice.

Methods: One hundred and twelve mice were randomly distributed into four major groups of twenty-eight mice per group. Each group was subdivided into four groups of seven mice each and fed with either standard animal feed (control), 10%, 20% or 40% CC diet (treatment groups) for thirty days. Weights of mice were monitored at interval of ten days. On the 31st day, mice from the control and various treatment groups were subjected to either the forced swim test, tail suspension test, three-chamber approach or novel object recognition tests. Twenty-four hours post neurobehavioural tests, animals were sacrificed, their brains and livers isolated, preserved in 10% buffered formalin and used for histological assays.

Results: There was a significant increase (p<0.05) in the duration of immobility in the forced swim and tail suspension tests in mice fed with higher concentrations of CC diet. A decrease in contact time spent on the novel object and with the unfamiliar mouse was observed in mice fed with 20 and 40% CC diet. While no cytotoxicity of neuronal and glial cells was observed in this study, hepatotoxicity was noticed in the livers of CC fed mice.

Conclusion: In this study, chronic consumption CC diet produced features characteristic of depression, cognitive dysfunction and hepatic damage in mice.