THE EFFECT OF ORAL ADMINISTRATION OF CURCUMIN ON DENDRITE MORPHOLOGY IN A RAT MODEL OF CHRONIC EXPOSURE TO ARSENIC

The aim of this study is to examine the neurotoxicity caused by chronic arsenic exposure, a global health problem, and the potential therapeutic effects of curcumin, a natural polyphenol, on this neuronal damage.
Wistar rats were divided into 3 groups: control, arsenic (2 mg/kg/day, for 6 weeks), and arsenic+curcumin (90 mg/kg/day, for 3 weeks) (short-term). Sodium arsenite and curcumin administered via oral gavage. Every rat was weighed weekly. Behavioral tests were performed to evaluate anxiety, memory, and motor functions. Brain tissues were processed by Golgi impregnation method. Cortical pyramidal neurons were examined using Neurolucida software. Dendritic branching, total dendrite length, dendritic spine density, and dendritic spine types were analyzed.
The arsenic group had significantly lower dendritic branching (p=0.0014), dendritic spine density (p<0.0001), thin-type dendritic spines (p=0.0011), and mushroom-type dendritic spines (p<0.0001) compared to the control group. The arsenic+curcumin group had significantly higher dendritic branching (p=0.0143), dendritic spine density (p<0.0001), and thin-type dendritic spines (p<0.0001) compared to the arsenic group. Furthermore, the total dendrite length was higher in the arsenic+curcumin group compared to the control group (p=0.0338) and the arsenic group (p=0.0052). Arsenic increased anxiety and decreased short-term memory, long-term memory, and distance. Curcumin did not affect behavioral characteristics. However, there was no statistically significant difference in rat weight.
Curcumin improved the morphological features of dendrites and dendritic spines of rats exposed to arsenic. These results emphasize the value of curcumin in neuroplasticity. Analysis of the 6-week-long-term curcumin treatment is ongoing.