title: Herbal melanin modulates tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6) and vascular endothelial growth factor (VEGF) production.
abstract: Recent studies have indicated that cytokines can enhance immunogenicity and promote tumor regression. However, the means for modulating cytokine production are not yet fully investigated. In this study we report the effects of a herbal melanin, extracted from Nigella sativa L., on the production of three cytokines [tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6) and vascular endothelial growth factor (VEGF)], by human monocytes, total peripheral blood mononuclear cells (PBMC) and THP-1 cell line. Cells were treated with variable concentrations of melanin and the expression of TNF-alpha, IL-6 and VEGF mRNA in cell lysates and secretion of proteins in the supernatants were detected by RT-PCR and ELISA. Melanin induced TNF-alpha, IL-6 and VEGF mRNA expression by the monocytes, PBMC and THP-1 cell line. On the protein level, melanin significantly induced TNF-alpha and IL-6 protein production and inhibited VEGF production by monocytes and PBMC. In the THP-1 cell line melanin induced production of all three cytokine proteins. These observations raise the prospects of using N. sativa L. melanin for treatment of diseases associated with imbalanced cytokine production and for enhancing cancer and other immunotherapies.
authors.affiliation: Biological Repository Center, Department of Molecular Pathology, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia.
authors.forename: A
authors.initials: A
authors.lastname: El-Obeid
authors.forename: S
authors.initials: S
authors.lastname: Al-Harbi
authors.forename: N
authors.initials: N
authors.lastname: Al-Jomah
authors.forename: A
authors.initials: A
authors.lastname: Hassib
mesh_terms: D000199:Actins / Q000032:analysis; D000328:Adult; D002460:Cell Line; D016207:Cytokines / Q000096:biosynthesis / Q000187:drug effects* / Q000235:genetics; D017931:DNA Primers / Q000737:chemistry; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis / Q000235:genetics; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology; D008543:Melanins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects* / Q000276:immunology; D031881:Nigella sativa / Q000737:chemistry*; D012333:RNA, Messenger / Q000032:analysis; D012639:Seeds / Q000737:chemistry; D023382:Toxicity Tests, Acute / Q000379:methods; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000187:drug effects / Q000235:genetics; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis / Q000187:drug effects / Q000235:genetics
chemical_list: D000199:Actins; D016207:Cytokines; D017931:DNA Primers; D015850:Interleukin-6; D008543:Melanins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D042461:Vascular Endothelial Growth Factor A