Cobalt exposure triggers impairments in cognitive and anxiety‐like behaviors, brain oxidative stress and inflammation, and hippocampo‐amygdala histomorphological alterations: Protective role of aqueous Prosopis africana seed extract

Abstract Background Cobalt toxicity has become a health concern in recent years, due to overexposure resulting in neurological impairments like dementia. With a growing interest in the therapeutic roles of herbs, in toxicity research, it’s worth looking into the curative effects of aqueous Prosopis africana seed extract, a plant rich in flavonoids on cobalt‐induced dementia‐like and anxiogenic behaviour. Method We treated rats with Cobalt (CoCl2) or CoCl2 in combination with aqueous Prosopis africana seed extract (PAE) orally for 14 days. Control rats received distilled water for the same period. Following treatments, behavioral experiments for cognition and anxiety, analysis for oxidative stress, inflammation, histological and immunohistochemical analysis were performed. Result Results revealed that CoCl2 reduced the exploration time, recognition index in the novel object recognition test, percentage spontaneous alternation in the Y‐maze tests, and reduced open arm entry and duration in elevated plus‐maze. However, treatment with PAE improved these parameters to levels comparable with those of the control group. Furthermore, PAE therapy reduced CoCl2‐induced surge in hydrogen peroxide, malondialdehyde, TNF‐α and IL‐1β levels in brain homogenate, while also increasing superoxide dismutase and reduced reduced‐glutathione activities. CoCl2 exposure resulted in obvious features of neurodegeneration like nuclear disintegration, nuclear shrinkage, and cytoplasmic vacuolations of the cells of the hippocampus and amygdala, with an increased expression of GFAP. The hippocampal and amygdala histology improved after PAE administration, while exacerbated GFAP expressions were attenuated. Conclusion These findings imply that PAE may be anxiolytic and can help reduce cognitive impairments and hippocampal damage caused by CoCl2 neurotoxicity, via mechanisms that involve attenuation of oxidative stress and neuroinflammation.