The Effects of Iron Oxide Nanoparticles Administration on Depression Symptoms Induced by LPS in Male Wistar Rats

Depression is a mood disorder in which feelings of sadness, loss, anger, or frustration interfere with everyday life for one to several weeks. Several studies have shown that iron nanoparticles have neuroprotective and anti-inflammatory effects. This study aimed to evaluate anti-depressive effect of iron nanoparticles in male rats.

Depression was induced by Lipopolysaccharide (LPS) adminstration. Rats were randomly assigned into six groups (10 in each group): 1) control (sterile saline solution; 200 μL, IP); 2) LPS (LPS;100 μg/kg, IP); 3) Low dose Iron Nanoparticle (LINP) (1 mg/kg, IP); 4) High dose Iron Nanoparticle (HINP), 5 mg/kg IP); 5) LPS/LINP (LPS; 100μg/kg IP+INP 1 mg/kg IP); and 6) LPS/HINP (LPS; 100 μg/kg IP+INP 5 mg/kg IP). All injections were performed every other day. To assess the effect of iron nanoparticles on depression symptoms, rats were subjected to two behavioral tests: Forced Swim Test (FST) and Open Field Test (OFT).

Iron nanoparticles treatment in 1 mg/kg and 5 mg/kg doses groups significantly improved depression symptoms when assessed by OFT and FST. In OFT, the number of line crossings, entrance to central square, rearing and duration of attending in central square increased after iron nanoparticles adminstration in depressed rats. Iron nanoparticles adminstration reduced immobility time confirmed by FST and OFT. Also, iron nanoparticles adminstration significantly increased duration of swimming in FST depressed rats.

Our results for the first time showed potential advantageous effect of iron nanoparticles administration in attenuating depression symptoms, which was possibly mediated by modulation of neurotransmitters and anti-inflammatory effects of iron nanoparticles.