Anat Cell Biol.  2020 Sep;53(3):355-365. 10.5115/acb.18.169.

Curcumin supplementation shows modulatory influence on functional and morphological features of hippocampus in mice subjected to arsenic trioxide exposure

• Mehta K
• Kaur B
• Pandey KK
• Kaler S
• Dhar P

• KMID: 2507648
• DOI: http://doi.org/10.5115/acb.18.169

Abstract

Since, oxidative stress has been suggested as one of the mechanisms underlying arsenic-induced toxicity, the present study focused on the role of antioxidant (curcumin) supplementation on behavioral, biochemical, and morphological alterations with context to mice hippocampus (CA1) following arsenic trioxide (As₂O₃) administration. Healthy male Swiss albino mice were divided into control and experimental groups. As₂O₃ (2 mg/kg bw) alone or along with curcumin (100 mg/kg bw) was administered to experimental groups by oral route for 45 days whereas the control groups received either no treatment or vehicle for curcumin. Animals were subjected to behavioral study towards the end of the experimental period (day 33–45). On day 46, the brain samples were obtained and subjected either to immersion fixation (for morphometric observations) or used afresh for biochemical test. Behavioral tests (open field, elevated plus maze, and Morris water maze) revealed enhanced anxiety levels and impairment of cognitive functions in As₂O₃ alone treated groups whereas a trend of recovery was evident in mice simultaneously treated with As₂O₃ and curcumin. Morphological observations showed noticeable reduction in stratum pyramidale thickness (CA1), along with decrease in density and size of pyramidal neurons in As₂O₃ alone exposed group as compared to As₂O₃ +Cu co-treated group. Hippocampal glutathione levels were found to be downregulated in animals receiving As₂O₃ as against the levels of controls and curcumin supplemented animals, thereby, suggestive of beneficial role of curcumin on As₂O₃ induced adverse effects.

Keyword

Arsenic trioxide (As₂O₃); Hippocampus; Cognition; Oxidative stress; Curcumin

Figure

• 

  Fig. 1 Percentage center time (A) and total distance traveled (B) during open field test in control and experimental groups. Percentage open arm entries (C) and percentage open arm time (D) during elevated plus maze test in control and experimental groups. Mean escape latency (E) and mean distance traveled (F) during acquisition phase of Morris water maze (MWM) test in control and experimental groups. Time spent in platform quadrant (G) and number of platform crossings (H) during probe trial of MWM test in control and experimental groups. Values are presented as mean±SD. *P≤0.05, **P≤0.01, ***P≤0.001; ns, non-significant.

• 

  Fig. 2 Reduced glutathione (GSH) levels in mice hippocampus. Values are presented as mean±SD. *P≤0.05, **P≤0.01.

• 

  Fig. 3 Cresyl violet (CV) stained coronal sections of CA1 from control (A) and experimental animals (B, As2O3 alone; C, curcumin alone; D, As2O3+curcumin). Well-arranged 3–5 cell layer Stratum pyramidale (SP) with densely packed pyramidal neurons showing large/round-oval nucleus, marked by star and 1–3 distinct nucleoli marked by asterisk (A, C, D). (B) SP (1–3 cell layer thick, marked by vertical bar) shows disruption, evident by loosely packed pyramidal neurons, indicated by double head arrows with shrunken nuclei marked by oblique arrows. SO, Stratum oriens; SR, Stratum radiatum.

Reference

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