Abstract: Chronic opioid intake leads to opioid dependence and withdrawal syndrome after opioid cessation. Morphine and Thymoquinone (TQ) are both opioid receptor stimulating compounds, although, they have different pharmacological origins. Morphine is a natural opioid derivative whereas TQ is one of the main pharmacologically active compounds from Nigella sativa oils. This study was carried out to study the effects of TQ on cAMP concentration mediated by chronic morphine treatment in opioid receptor expressing cell line (U87 glioblastoma cells). U87 cells was grown in tissue culture flasks with RPMI 1640 medium containing 1 mmol/L L-glutamine, supplemented with 10% (v/v) Fetal Bovine Serum (FBS) and 1% (w/v) penicillin/streptomycin. The cell viability was assessed by the trypan blue dye and manually counted using a haemocytometer. The MTT assay was used to determine the cytotoxic effects of morphine and TQ. The cAMP concentration in the cells was determined using the Cell Biolabs, Inc. cAMP ELISA Kit. Co-treatment of morphine and TQ significantly attenuate the increase in cAMP content produced by morphine after chronic morphine treatment (*p<0.05). These finding suggest that TQ could possibly reduce opioid dependence on chronic morphine treatment at cellular level by reducing the up-regulation of cAMP level.
Liyana Hazwani Mohd Adnan, Nasir Mohamad, Khairi Che Mat, Nor Hidayah Abu Bakar, Siti Norhajah Hashim, Mohd Halim Mohd Shariff and Mohd Izuddin Mansor, 2018. Attenuation of Morphine-Induced Camp Overshoot by Thymoquinone in Opioid Receptor Expressing Cells (U87 MG) Mediated by Chronic Morphine Treatment. Journal of Engineering and Applied Sciences, 13: 8906-8911.