The Role of the Comet Assay in Investigating the Genotoxic and Anti-genotoxic Effects of Plant Secondary Metabolites: A Current Review

Öz

Plant secondary metabolites (SMs) are organic compounds produced by plants that often exhibit significant pharmacological and biological activities. They are a primary source for drug discovery and have wide-ranging applications in agriculture, food, textiles, and the dye industry. Despite their beneficial effects, the potential toxicity of specific secondary metabolites can limit their use. Consequently, evaluating the genotoxic and/or antigenotoxic potential of SMs, especially those intended for direct human exposure, is crucial. Various experimental approaches, including in vitro and in vivo methods, have been used for this purpose. This review begins by discussing the definition, classification, and mechanisms of action of plant secondary metabolites. It then focuses on studies that have employed the Comet assay to investigate their genotoxic/antigenotoxic properties. The literature reviewed is limited to studies that utilized the Comet assay, which is widely regarded as a reliable method for detecting DNA strand breaks and assessing genotoxicity/antigenotoxicity. Based on the studies reviewed, it has been observed that terpenes mostly have genotoxic effects on various cancer cell lines, whereas phenolic compounds exhibit significant antigenotoxic effects in the tissues studied. Secondary metabolites containing nitrogen and sulfur, on the other hand, stand out for their antigenotoxic and anticancer properties. In general, the genotoxic, antigenotoxic, anticancer, and antioxidative effects of plant secondary metabolites vary depending on the application concentration, the type of cell or tissue targeted, and the duration of exposure. Further research is needed to elucidate the mechanisms of action of SMs. Due to its sensitivity and reliability, the comet assay is expected to continue to be widely used in future genotoxicity and antigenotoxicity studies.

Anahtar Kelimeler

• Plant Secondary Metabolites
• Genotoxicity Anti-genotoxicity
• Comet/Single Cell Gel Electrophoresis Assay

Bitki Sekonder Metabolitlerinin Genotoksik ve Anti-genotoksik Etkilerinin Araştırılmasında Komet Testinin Rolü: Güncel Bir Derleme

Öz

Bitki sekonder metabolitleri (SM'ler), genellikle önemli farmakolojik ve biyolojik aktiviteler sergileyen bitkiler tarafından üretilen organik bileşiklerdir. SM’ler, ilaç keşfi için önemli bir kaynaktır ve ayrıca tarım, gıda, tekstil ve boya endüstrisinde geniş kapsamlı uygulamalara sahiptir. Yararlı etkilerine rağmen, bazı sekonder metabolitlerin potansiyel toksisitesi kullanımlarını sınırlayabilmektedir. Sonuç olarak, SM'lerin, özellikle doğrudan insan maruziyeti için tasarlananların, genotoksik ve/veya anti-genotoksik potansiyelinin değerlendirilmesi çok önemlidir. Bu amaçla hem in vitro hem de in vivo yöntemler dahil olmak üzere çeşitli deneysel yaklaşımlar kullanılmaktadır. Bu derleme, bitki sekonder metabolitlerinin tanımı, sınıflandırılması ve etki mekanizmalarını tartışarak başlamaktadır. Daha sonra, genotoksik ve anti-genotoksik özelliklerini araştırmak için Komet testini kullanan çalışmalara odaklanmıştır. İncelenen kaynaklar, DNA ipliğindeki kırıkları tespit etmek ve genotoksisiteyi/anti-genotoksisiteyi değerlendirmek için yaygın olarak uygulanan ve güvenilir bir yöntem olarak kabul edilen Komet testini kullanan çalışmalarla sınırlandırılmıştır. İncelenen çalışmalar doğrultusunda, terpenlerin çoğunlukla çeşitli kanser hücre hatları üzerinde genotoksik etkilere sahip olduğu, buna karşın fenolik bileşiklerin çalışılan dokularda belirgin biçimde anti-genotoksik etkiler gösterdiği görülmektedir. Azot ve sülfür içeren SM’ler ise özellikle anti-genotoksik ve anti-kanser özellikleriyle öne çıkmaktadır. Genel olarak bitki sekonder metabolitlerinin genotoksik, anti-genotoksik, anti-kanser ve anti-oksidatif etkileri; uygulama konsantrasyonuna, hedef alınan hücre veya doku tipine ve maruz kalma süresine bağlı olarak değişkenlik göstermektedir. Bütün bu verilere rağmen, SM’lerin etki mekanizmalarının aydınlatılabilmesi için daha ileri düzeyde araştırmalara ihtiyaç duyulmaktadır. Hassas ve güvenilir bir test olması nedeniyle Komet testinin gelecekteki genotoksisite ve anti-genotoksisite çalışmalarında yaygın olarak kullanılmaya devam etmesi beklenmektedir.

Anahtar Kelimeler

• Bitki Sekonder Metabolitleri
• Genotoksisite- Anti-genotoksisite
• Komet/Tek Hücre Jel Elektroforez Testi

Kaynakça

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