Social behavior effects of diphenyl dimethyl bicarboxylate (DDB) in the sensory contact model.

Sensory contact model (SCM) permits the evolution of diverse psychopathological states by the repeated antagonistic interactions between male mice. Biphenyl dimethyl dicarboxylate (DDB) is used as a hepatoprotective agent. The present work aimed to study the possible effects of DDB on social behavior developed by SCM by studying its effects on the transformation process to aggressive and submissive behaviors. Besides, measuring behavioral changes using the open field test (OFT) and the elevated plus maze test (EPM), neurochemical parameters [serotonin (5HT), norepqinephrine (NE), and dopamine(DA)], and immunological changes (total leucocyte count, differential leucocytic count, and evaluation of bone marrow lymphocytes count and viability assessment). Adult male Swiss mice were used; DDB was given in a dose of 100 mg/kg by oral gavage daily for 2 weeks from the fifth day to the last day of the SCM. The present study concluded that administration of DDB to the SCM involved animals was shown to be associated with significant positive impacts on the behavior of depressed partner in the SCM which were manifested by decreased latency and increased ambulation and rearing in OFT, increased number of entry in the open arm/total no of entries in EPM. This was associated with changes in brain levels of neurotransmitters which were manifested by increased NE and decreased DA, as well as the examined immunity related parameters which were manifested by increased total leucocyte count, bone marrow lymphocytes, and monocytes. So DDB can be used as a supportive antidepressant agent in patients with liver impairment and should be avoided in aggressive ones. However, more randomized controlled trials should be carried out to ascertain these effects.