Histomorphological and Neurobehavioral Study of Effect of Spinacia Oleracea (Spinach) Ethanolic Leaf Extract on Restraint Chronic Stress-Induced Neurodegeneration in Hippocampus of Experimental Rats

Background and objective: Spinach (Spinacia oleracea) is nutritionally rich in antioxidants. This work aimed at evaluating the therapeutic potential of ethanolic leaf extract of Spinacia oleracea (SO) on restraint chronic stress (RCS)-induced neurodegeneration.

Methods and study design: Twenty-four male Wistar rats, weighing 180–200 grams, were divided into six different groups, namely: the normal control group (0.5ml of normal saline), the negative control (RCS and normal saline only), the low dose (200mg/kg), the medium dose (400mg/kg), the high dose (800 mg/kg) and fluoxetine (20mg/kg). Restraint chronic stress (RCS) were induced 2hours daily for 21 days followed by treatment with Spinacia Oleracea for another 14 days. Neurobehavioral assessments, including the Y-maze, novel object recognition, and elevated plus maze (EPM) tests, was done and video tapped to facilitate accurate scoring. After treatment is done, blood sample was collected for oxidative stress (SOD, MDA, GSH) and neuroinflammatory marker (IL-1β, TNF-α) assay. Histologically, using hematoxylin and eosin (H&E) stain, neuronal alterations were evaluated in the hippocampus sample.

Results: S. Oleracea (200mg/kg and 800mg/kg) treatment significantly cured RCS-induced memory impairment and cognition on Y-maze, and NORT respectively and time spent in the open arms of the EPM significantly raised (p < 0.05). Administration of SO reduced MDA level while increasing SOD and glutathione-S-transferase activity in the treatment groups and significantly reduced RCS-induced elevation of (TNF-α) and Interleukin-1 beta (IL-1β) (p<0.05) which are necrosis factor for tumor. Furthermore, SO enhanced histoarchitecture of hippocampus in the groups with treatment in compression to the negative control.

Conclusion: S. Oleracea is therapeutic against chronic stress-induced neurodegeneration in the hippocampus.

Keywords: Restraint Chronic stress, Spinacia Oleracea, Neurodegeneration, Neurobehavior