title: Leishmanicidal and cytotoxic activities of Nigella sativa and its active principle, thymoquinone.
abstract: BACKGROUND
  Leishmaniasis is a complex disease with a broad spectrum of clinical presentations.
  
  
  OBJECTIVE
  We evaluated the anti-leishmanial effects of Nigella sativa L. (Ranunculaceae) against Leishmania tropica and Leishmania infantum with an in vitro model.
  
  
  METHODS
  Antileishmanial effects of essential oil and methanolic extract of N. sativa (0-200 µg/mL) and thymoquinone (0-25 µg/mL) on promastigotes of both species and their cytotoxicity activities against murine macrophages were evaluated using the MTT assay at 24, 48, and 72 h. Moreover, their leishmanicidal effects against amastigotes were investigated in a macrophage model, for 48 and 72 h.
  
  
  RESULTS
  The findings showed that essential oil (L. tropica IC50 9.3 μg/mL and L. infantum IC50 11.7 μg/mL) and methanolic extract (L. tropica IC50 14.8 μg/mL and L. infantum IC50 15.7 μg/mL) of N. sativa, particularly thymoquinone (L. tropica IC50 1.16 μg/mL and L. infantum IC50 1.47 μg/mL), had potent antileishmanial activity on promastigotes of both species after 72 h. In addition, essential oil (L. tropica IC50 21.4 μg/mL and L. infantum IC50 26.3 μg/mL), methanolic extract (L. tropica IC50 30.8 μg/mL and L. infantum IC50 34.6 μg/mL), and thymoquinone (L. tropica IC50 2.1 μg/mL and L. infantum IC50 2.6 μg/mL) mediated a significant decrease in the growth rate of amastigote forms of both species. Thymoquinone (CC50 38.8 μg/mL) exhibited higher cytotoxic effects against murine macrophages than the other extracts.
  
  
  CONCLUSIONS
  N. sativa, especially its active principle, thymoquinone, showed a potent leishmanicidal activity against L. tropica and L.infantum with an in vitro model.
authors.affiliation: Department of Medical Parasitology and Mycology, Kerman University of Medical Sciences , Kerman , Iran .
authors.forename: Hossein
authors.initials: H
authors.lastname: Mahmoudvand
authors.forename: Razieh
authors.initials: R
authors.lastname: Tavakoli
authors.forename: Fariba
authors.initials: F
authors.lastname: Sharififar
authors.forename: Keyhan
authors.initials: K
authors.lastname: Minaie
authors.forename: Behrouz
authors.initials: B
authors.lastname: Ezatpour
authors.forename: Sareh
authors.initials: S
authors.lastname: Jahanbakhsh
authors.forename: Iraj
authors.initials: I
authors.lastname: Sharifi
mesh_terms: D000818:Animals; D000981:Antiprotozoal Agents / Q000302:isolation & purification / Q000494:pharmacology* / Q000627:therapeutic use; D016227:Benzoquinones / Q000302:isolation & purification / Q000494:pharmacology* / Q000627:therapeutic use; D003603:Cytotoxins / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use; D018314:Leishmania infantum / Q000187:drug effects* / Q000502:physiology; D007895:Leishmania tropica / Q000187:drug effects* / Q000502:physiology; D007896:Leishmaniasis / Q000188:drug therapy; D008264:Macrophages / Q000187:drug effects / Q000502:physiology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D031881:Nigella sativa; D009822:Oils, Volatile; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology* / Q000627:therapeutic use; D012639:Seeds
chemical_list: D000981:Antiprotozoal Agents; D016227:Benzoquinones; D003603:Cytotoxins; D009822:Oils, Volatile; D010936:Plant Extracts; C003466:thymoquinone
keywords: Black cumin; Leishmania infantum; Leishmania tropica