Synergistic effect of combination of phenethyl isothiocyanate and sulforaphane or curcumin and sulforaphane in the inhibition of inflammation.
OBJECTIVE
Accumulating evidence from epidemiologic and clinical studies indicates that chronic inflammatory disorders harbor an increased risk of cancer development. Curcumin (CUR) has been strongly linked to the anti-inflammatory effect. On the other hand, isothiocyanates such as sulforaphane (SFN) and phenethyl isothiocyanate (PEITC) are strong phase-II detoxifying/antioxidant enzymes inducer. Therefore it is interesting to see if combination of these drugs can inhibit inflammation with higher combined efficacies.


METHODS
We used nitric oxide (NO) assay to assess the synergism of the different combinations of CUR, SFN and PEITC. The inflammatory markers, e.g. iNOS, COX-2, prostaglandin E2 (PGE2), tumor necrosis factor (TNF) and interleukin-1 (IL-1) levels were determined using RT-PCR, Western blot and ELISA assays.


RESULTS
We report that combination of PEITC + SFN or CUR + SFN has a synergistic effect in down-regulating inflammation markers like TNF, IL-1, NO, PGE2. The synergism is probably due to the synergistic induction of phase II/antioxidant enzymes including heme-oxygenase1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO-1).


CONCLUSIONS
Our data suggest that CUR + SFN and PEITC + SFN combinations could be more effective than used alone in preventing inflammation and possibly its associated diseases including cancer.
Cheung
Ka Lung
KL
Graduate Program in Pharmaceutical Science, Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.
Khor
Tin Oo
TO
Kong
Ah-Ng
AN
D000894:Anti-Inflammatory Agents, Non-Steroidal; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D015415:Biomarkers; D002460:Cell Line; D003474:Curcumin / Q000494:pharmacology*; D051546:Cyclooxygenase 2 / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D004357:Drug Synergism; D007375:Interleukin-1 / Q000378:metabolism; D017879:Isothiocyanates / Q000494:pharmacology*; D008070:Lipopolysaccharides; D008264:Macrophages / Q000187:drug effects / Q000473:pathology; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013454:Sulfoxides; D013861:Thiocyanates / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D000894:Anti-Inflammatory Agents, Non-Steroidal; D016588:Anticarcinogenic Agents; D015415:Biomarkers; D007375:Interleukin-1; D017879:Isothiocyanates; D008070:Lipopolysaccharides; D013454:Sulfoxides; D013861:Thiocyanates; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; C058305:phenethyl isothiocyanate; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2; C016766:sulforaphane; D003474:Curcumin; D015232:Dinoprostone