Evaluation of the Genotoxic Potential against H2O2-Radical-Mediated DNA Damage and Acute Oral Toxicity of Standardized Extract of Polyalthia longifolia Leaf
Authors: Jagat R Kanwar
Yeng Chen
Sreenivasan Sasidharan
Subramanion L Jothy
Journal: Evidence-based Complementary and Alternative Medicine (2013)
Discipline: CLINICAL MEDICINE
Keywords: Medicinal plants; Polyalthia longifolia leaf extract; antioxidant; genotoxic effects; plasmid relation assay
Affiliations: Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM), 11800 Penang, Malaysia., Dental Research & Training Unit, and Oral Cancer Research and Coordinating Centre (OCRCC), Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, Nanomedicine-Laboratory of Immunology and Molecular Biomedical Research (LIMBR), School of Medicine (SoM), Faculty of Health, Institute for Frontier Materials (IFM), Deakin University, Waurn Ponds, VIC 3217, Australia, Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia (USM), 11800 Penang, Malaysia

Abstract:  Medicinal plants have been used in medicoculturally diverse countries around the world, where it is a part of a time-honoured tradition that is respected even today. Polyalthia longifolia leaf extract has been previously reported as an efficient antioxidant in vitro. Hence, the genotoxic effects of P. longifolia leaf were investigated by using plasmid relation, comet, and Allium cepa assay. In the presence of (‚à? OH radicals, the DNA in supercoil was start nicked into open circular form, which is the product of the single-stranded cleavage of supercoil DNA and quantified as fragmented separate bands on agarose gel in plasmid relation assay. In the plasmid relation and comet assay, the P. longifolia leaf extract exhibited strong inhibitory effects against H2O2-mediated DNA damage. A dose-dependent increase of chromosome aberrations was also observed in the Allium cepa assay. The abnormalities scored were stickiness, c-mitosis, bridges, and vagrant chromosomes. Micronucleated cells were also observed at the interphase. The results of Allium cepa assay confirmed that the methanol extracts of P. longifolia exerted no significant genotoxic or mitodepressive effects at 100 Œº g/mL. Thus, this study demonstrated that P. longifolia leaf extract has a beneficial effect against oxidative DNA damage. This experiment is the first report for the protective effect of P. longifolia on DNA damage-induced by hydroxyl radicals. Additionally in acute oral toxicity study, female rats were treated at 5000 mg/kg body weight of P. longifolia leaf extract and observed for signs of toxicity for 14 days. P. longifolia leaf extract did not produce any treatment-related toxic effects in rats. 

Retracted: No

PubPeer comments:
 Hi, I was surprised by the sentence u201c*HPV genotyping by dideoxy (Sanger) sequencing is currently the reference method of choice for clinical diagnostics*.u201d If I use the following reference , I believe these are the FDA approved technologies for HPV typing: 1)tDigene* HC2 (Qiagen) 2)tCervista HPV HR (Hologic) 3)tCervista HPV 16 18 (Hologic) 4)tAptima HPV (Hologic) 5)tAptima HPV 16, 18 45 (Hologic) 6)tCobas HPV (Roche) 7)tOnclarity HPV (BD) From what I understand, I believe these can be described by the following overall methodologies, all using Hybridization rather than Sanger sequencing (but please correct me if I am wrong): **Digene**: PCR + Hybridization **Cervista**: PCR + Hybridization **Aptima**: E6 E7 PCR + Hybridization ) **Cobas**: PCR + Hybridization **Onclarity**: Cell isolation + PCR + Hybridization (http: legacy.bd.com resource.aspx?IDX=30114) On the research side, I often see Illumina sequencing experiments (such as [Conway et al. 2012, PMID: 22240447] ; [Yi et al. 2014, PMID: 24838323] ; [Bik et al. 2019, PMID: 31042762] ; [Cullen et al. 2015, PMID: 26645052] ; [Lagstrom et al. 2019, PMID: 30679491] , etc.), and I donu2019t believe I see many Sanger studies (at least in the genomics literature). **So, can you please explain why you believe Sanger sequencing is considered the method of choice?** My understanding is that PCR + Hybridization is currently most frequently used in the clinic, and Illumina sequencing may become more common in the future (but I wouldnu2019t have considered Sanger sequencing to be the preferred method, particularly if genotyping of co-infections is desired). Thank You, Charles ,