Self-microemulsifying drug delivery system (SMEDDS) of curcumin attenuates depression in olfactory bulbectomized rats

Current therapies for depression remain limited and plagued by various side effects. Problems associated with curcumin administration include poor aqueous solubility and bioavailability issues. Hence to overcome these, curcumin self micro emulsifying drug delivery system (SMEDDS) which will result in a nanosize emulsion droplets when administered in vivo were formulated in the present study.

Depression was induced by bilateral olfactory bulbectomy and the animals were randomized into 8 groups as normal, control [(vehicle 10 ml/kg, p.o., (per oral)], pure curcumin (10, 20, 40 mg/kg, p.o.), and curcumin SMEDDS (10, 20, 40 mg/kg, p.o). After 14 days of respective treatment, behavioral parameters such as open field test (OFT), ambulation counts and passive avoidance response (PAR) were evaluated. At the end of experiments, blood was withdrawn from r.o.p (retro orbital plexus) for serum cortisol estimation.

In OFT, increased central area frequency, peripheral area frequency, central area duration and decreased rearing and grooming were recorded with an increased ambulation counts. In PAR, significant reduction in number of trials and step down from platform was observed in the animals treated with test drug. Serum cortisol level was also found to be decreased in the test groups.

Behavioral and biochemical estimations in the present study revealed the improved brain permeability and further increase in biological activity of curcumin SMEDDS.