Black Seed (Nigella Sativa) and its Constituent Thymoquinone as an Antidote or a Protective Agent Against Natural or Chemical Toxicities

Nigella sativa (N. sativa), which belongs to the botanical family of Ranunculaceae, is a widely used medicinal plant all over the world. N. sativa seeds and oil have been used in the treatment of different diseases. Various studies on N. sativa have been carried out and a broad spectrum of its pharmacological actions have been established which include antioxidant, antidiabetic, anticancer, antitussive, immunomodulator, analgesic, antimicrobial, anti-inflammatory, spasmolytic and bronchodilator. This is also indicated that the majority of the therapeutic effects of N. sativa are due to the presence of thymoquinone (TQ) that is main bioactive constituent of the essential oil. According to several lines of evidence, the protective effects of this plant and its main constituent in different tissues including brain, heart, liver, kidney and lung have been proved against some toxic agents either natural or chemical toxins in animal studies. In this review article, several in vitro and animal studies in scientific databases which investigate the antidotal and protective effects of N. sativa and its main constituents against natural and chemical induced toxicities are introduced. Because human reports are rare, further studies are required to determine the efficacy of this plant as an antidote or protective agent in human intoxication.