Effect of Nigella Sativa on Cadmium-Induced Toxicity in Colorectal Cancer

Effect of Nigella Sativa on Cadmium-Induced Toxicity in Colorectal Cancer
Samane Mohammadzadeh,^1,* Fatemeh Maghool,² Mohammad Hassan Emami,³
1. Poursina Hakim Digestive Diseases Research Center, IsfahanUniversity of Medical sciences, Isfahan, Iran
2. Poursina Hakim Digestive Diseases Research Center, IsfahanUniversity of Medical sciences, Isfahan, Iran
3. Poursina Hakim Digestive Diseases Research Center, IsfahanUniversity of Medical sciences, Isfahan, Iran
Introduction: Toxic heavy metals such as cadmium (Cd) may change the gut microbiome composition and increase the risk of colorectal cancer (CRC). Cd inhibits the growth of certain intestinal flora and re-shaped the community of gut microbiota both at the phylum and genus levels, increases pathogenic bacteria and decreases protective commensal bacteria (such as Lactobacillus); disrupts tight junctions, increases gut permeability, and bacterial translocation. This condition may develop resistance to antibiotic drugs. However, some agents with anti-bacterial properties can be used for targeting pathogenic flora in CRC. Nigella sativa (N.S) as a medicinal plant, traditionally used for reducing the risk of chronic diseases such as cancer due to its antibacterial and antioxidant properties. This review discusses how N.S may effect on Cd toxicity and pathogenic antibiotic resistant bacteria in CRC.
Methods: Relevant studies in electronic databases were selected by searching MEDLINE Library. Only relevant English published articles were included.
Results: Available evidence suggested that N.S exerts a protective effect against Cd toxicity and dysbiosis in CRC through the following mechanisms. Phenolic components of N.S have antibacterial properties against gram-positive and gram-negative bacteria. This medicinal plant scavenges free radicals, prevents cell damage from oxidative substances, improves the activity of anti-oxidative enzymes, chelates Cd, reduces and inhibits cadmium accumulation and alters the levels of beneficial metal ions in the body. On the other hand, N.S disrupts cell membrane of pathogenic bacteria and makes it more permeable, resulting in reducing pathogenic bacteria. N.S prevents intestinal epithelial barrier disruption and bacteria translocation, and increases probiotics bacteria, which can absorb, sequestrate and remove Cd and protect intestinal against bio accessibility of Cd.
Conclusion: N.S may attenuate toxicity of Cd in CRC through cadmium detoxification and beneficially reshape gut microbiota profiles, from dysbiosis to eubiosis.
Keywords: Nigella Sativa, Cadmium, Colorectal Cancer