Evaluation of the ameliorative potency of spirulina platensis against cerebellar damage induced by methotrexate in male rats: histopathological, ultrastructural, molecular, and biochemical studies

Background

Methotrexate (MTX), a drug utilized in cancer and rheumatoid arthritis treatment, is associated with acute and chronic neurodegenerative alterations. Spirulina platensis (SP) has several important phytochemical substances that act as free radical scavengers or natural antioxidants. The current study investigated the possible effects of the blue-green alga Spirulina platensis on cerebellar damage in male rats exposed to methotrexate. Forty (40) adult male albino rats were randomly divided into 4 groups (n = 10) and treated for one week: GI, the control group; GII was orally given 1000 mg SP/kg/daily, GIII was given a single intraperitoneal injection of MTX 75 mg/kg at the first day, and continued under the normal condition without other treatment till the end of the experiment, and GIV received both SP and MTX together with the same previous doses and duration. Neurobehavioral, histopathological, histochemical, immunohistochemical, ultrastructural, molecular, and biochemical data were recorded.

Results

MTX caused severe cerebellar degeneration in 3 cortical layers, especially the Purkinje layer. The Purkinje layer displayed a disrupted monolayer arrangement with pyknotic nuclei, a significant decrease in cell number, and shrunken cells surrounded by empty spaces. The molecular and granular layers are degenerated with elevated immunoreactions and gene expression of the glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule 1 (Iba-1), and neurofilament light chain antibody (NFL). Moreover, MTX significantly increased malondialdehyde (MDA) and myeloperoxidase (MPO) while decreasing the levels of reduced glutathione (GSH), serotonin, superoxide dismutase (SOD), acetylcholinesterase (ACHE), norepinephrine, and dopamine. These insults were noticeably mitigated by concomitant treatment with spirulina.

Conclusion

Spirulina improves neurological function by modulating the cerebellar damage elicited by MTX. This improvement may be attributed to the anti-inflammatory and antioxidant properties of spirulina.