scholarly journals Dietary Supplementation with the Red Seaweed Porphyra umbilicalis Protects against DNA Damage and Pre-Malignant Dysplastic Skin Lesions in HPV-Transgenic Mice

Marine Drugs ◽  
2019 ◽  
Vol 17 (11) ◽  
pp. 615 ◽  
Author(s):  
Susana Santos ◽  
Tiago Ferreira ◽  
José Almeida ◽  
Maria J. Pires ◽  
Aura Colaço ◽  
...  

Some diet profiles are associated with the risk of developing cancer; however, some nutrients show protective effects. Porphyra umbilicalis is widely consumed, having a balanced nutritional profile; however, its potential for cancer chemoprevention still needs comprehensive studies. In this study, we incorporated P. umbilicalis into the diet of mice transgenic for the human papillomavirus type 16 (HPV16), which spontaneously develop pre-malignant and malignant lesions, and determined whether this seaweed was able to block lesion development. Forty-four 20-week-old HPV+/− and HPV−/− mice were fed either a base diet or a diet supplemented with 10% seaweed. At the end of the study, skin samples were examined to classify HPV16-induced lesions. The liver was also screened for potential toxic effects of the seaweed. Blood was used to study toxicological parameters and to perform comet and micronucleus genotoxicity tests. P. umbilicalis significantly reduced the incidence of pre-malignant dysplastic lesions, completely abrogating them in the chest skin. These results suggest that P. umbilicalis dietary supplementation has the potential to block the development of pre-malignant skin lesions and indicate its antigenotoxic activity against HPV-induced DNA damage. Further studies are needed to establish the seaweed as a functional food and clarify the mechanisms whereby this seaweed blocks multistep carcinogenesis induced by HPV.

Viruses ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 170 ◽  
Author(s):  
Chia-Yu Chang ◽  
Wei-Tao Chen ◽  
Takeshi Haga ◽  
Nanako Yamashita ◽  
Chi-Fen Lee ◽  
...  

Papillomavirus (PV) mainly infects the squamous epithelium and may potentially lead to benign or even malignant cutaneous lesions. However, the malignant transforming ability has been identified in several types of PVs. In humans, papillomavirus (HPV) type 16 and 18 are the most prevalent causative agents of cervical cancer. Therefore, vaccines are being developed to protect against these types. For dogs, there have been limited investigations into the association of different canine papillomavirus (CPV) genotypes with malignant lesions. Understanding the high-risk CPV genotype(s) responsible for these malignant lesions would contribute to the development of interventions for preventing CPV-induced carcinomas. In the present study, a retrospective cohort of 102 pathologically confirmed papillomas and 212 squamous cell carcinomas (SCCs) were included. The viral genome and antigens in the formalin-fixed paraffin-embedded (FFPE) tissues were detected using PCR targeting pan PV E1 and COPV L1 genes and by immunohistochemistry staining (IHC), respectively. PVs were successfully detected from 11 FFPE cutaneous tissues and four oral tissues using pan PV E1- and COPV L1-based PCR, respectively. After sequencing, CPV 1, CPV 2, and CPV 6 were detected in the benign lesions using PCR and were confirmed through IHC. While CPV 9 and CPV 15 were first detected in the SCCs of dogs, CPV 16 was most often detected in SCC specimens. The association and confirmative demonstration of viral genes and intralesional antigens of CPV 9, CPV 15, and CPV 16 in SCCs highlight the potential risk of these genotypes of CPVs in malignant transformation.


1993 ◽  
Vol 26 (2) ◽  
pp. 215-230
Author(s):  
Gerry F. Funk ◽  
Henry T. Hoffman ◽  
Keith D. Carter
Keyword(s):  

2011 ◽  
Vol 49 (8) ◽  
pp. 1674-1683 ◽  
Author(s):  
Dobrosława Gradecka-Meesters ◽  
Jadwiga Palus ◽  
Gabriela Prochazka ◽  
Dan Segerbäck ◽  
Elżbieta Dziubałtowska ◽  
...  

2008 ◽  
Vol 83 (3) ◽  
pp. 287-287
Author(s):  
Denise Grotto ◽  
Gustavo R. M. Barcelos ◽  
Juliana Valentini ◽  
Lusânia M. G. Antunes ◽  
José Pedro F. Angeli ◽  
...  

Medicine ◽  
2021 ◽  
Author(s):  
Catherine Drislane ◽  
Katie Lacy
Keyword(s):  

Author(s):  
Daisy Liu

Snow fungus, Tremella fuciformis, has been demonstrated to have numerous health benefits including purported chemopreventive properties due to free radical-scavenging ability. Protective effects derived from snow fungus polysaccharides are evaluated on Chinese hamster lung fibroblasts (CCL-39) exposed to carcinogen benzo[a]pyrene known to cause free radical formation and oxidative stress to cells. In this experiment, it was hypothesized that the naturally occurring polysaccharides in snow fungus are able to protect against or reduce oxidative stress-induced DNA damage. Polysaccharides were isolated through an alkaline extraction and in-vitro digestion. DNA damage was measured using the single-cell gel electrophoresis comet assay after exposure to benzo[a]pyrene and polysaccharide extract to lung fibroblasts. Results were calculated using the mean and standard deviation data of tail length and area, respectively. Each damaged cell was measured and analyzed through ImageJ Editing Software. The results indicate a promising trend which depict snow fungus polysaccharides yielding lower levels of DNA damage compared to cells exposed to benzo[a]pyrene and compared to the negative control (phosphate buffered saline and Dulbecco’s cell medium). This study suggests polysaccharides from Tremella fuciformis could truly prevent cellular DNA damage by protecting against oxidative stress.


Author(s):  
Maryam M. Asgari ◽  
David J. Leffell
Keyword(s):  

2010 ◽  
Vol 13 (2) ◽  
pp. 231 ◽  
Author(s):  
Haydar Çelik ◽  
Emel Arinç

PURPOSE. Idarubicin is a synthetic anthracycline anticancer drug widely used in the treatment of some hematological malignancies. The studies in our laboratory have clearly demonstrated that idarubicin can undergo reductive bioactivation by NADPH-cytochrome P450 reductase to free radicals with resulting formation of DNA strand breaks, which can potentially contribute to its genotoxic effects [Çelik, H., Arinç, E., Bioreduction of idarubicin and formation of ROS responsible for DNA cleavage by NADPH-cytochrome P450 reductase and its potential role in the antitumor effect. J Pharm Pharm Sci, 11(4):68-82, 2008]. In the current study, our aim was to investigate the possible protective effects of several phenolic antioxidants, quercetin, rutin, naringenin, resveratrol and trolox, against the DNA-damaging effect of idarubicin originating from its P450 reductase-catalyzed bioactivation. METHODS. DNA damage was measured by detecting single-strand breaks in plasmid pBR322 DNA using a cell-free agarose gel method. RESULTS. Our results indicated that, among the compounds tested, quercetin was the most potent antioxidant in preventing DNA damage. Quercetin significantly decreased the extent of DNA strand breaks in a dose-dependent manner; 100 μM of quercetin almost completely inhibited the DNA strand breakage. Unlike quercetin, its glycosidated conjugate rutin, failed to provide any significant protection against idarubicin-induced DNA strand breaks except at the highest concentration tested (2 mM). The protective effects of other antioxidants were significantly less than that of quercetin even at high concentrations. Quercetin was found to be also an effective protector against DNA damage induced by mitomycin C. CONCLUSION. We conclude that quercetin, one of the most abundant flavonoids in the human diet, is highly effective in reducing the DNA damage caused by the antitumor agents, idarubicin and mitomycin C, following bioactivation by P450 reductase.


2016 ◽  
Vol 64 (4) ◽  
pp. 961.1-961
Author(s):  
S Kim ◽  
P Cheresh ◽  
RP Jablonski ◽  
DW Kamp ◽  
M Eren ◽  
...  

RationaleConvincing evidence has emerged that impaired alveolar epithelial cell (AEC) injury and repair resulting from ‘exaggerated’ lung aging and mitochondrial dysfunction are critical determinants of the lung fibrogenic potential of toxic agents, including asbestos fibers, but the mechanisms underlying these findings is unknown. We showed that the extent of AEC mitochondrial DNA (mtDNA) damage and apoptosis are critical determinants of asbestos-induced pulmonary fibrosis (Cheresh et al AJRCMB 2014, Kim et al JBC 2014). Klotho is an age-inhibiting gene and Klotho-deficient mice demonstrate a premature aging phenotype that includes a reduced lifespan, arteriosclerosis, and lung oxidative DNA damage, and that Klotho attenuates hyperoxic-induced AEC DNA damage and apoptosis (Ravikumar et al AJP-Lung 2014). We reason that Klotho has an important role in limiting pulmonary fibrosis by protecting the AECs from oxidative stress.MethodsQuantitative PCR-based measurement of mtDNA damage was assessed following transient transfection with wild-type Klotho, Klotho siRNA or AKT siRNA in A549 and/or MLE-12 cells for 48 hrs followed by exposure to either amosite asbestos (25 µg/cm2) or H2O2 (200 µM) for 24 hrs. Apoptosis was assessed by cleaved caspase-9/3 levels and DNA fragmentation assay. Murine pulmonary fibrosis was analyzed in male 8–10 week old WT (C3H/C57B6J) mice or Klotho heterozygous knockout (Kl+/−) mice following intratracheal instillation of a single dose of 100 µg crocidolite asbestos or titanium dioxide (negative control) using histology (fibrosis score by Masson's trichrome staining) and lung collagen (Sircoll assay).ResultsCompared to control, amosite asbestos or H2O2 reduces Klotho mRNA/protein expression. Notably, silencing of Klotho promotes oxidative stress-induced AEC mtDNA damage and apoptosis whereas Klotho-enforced expression (EE) and Euk-134, a mitochondrial ROS scavenger, are protective. Interestingly, Kl+/− mice have increased asbestos-induced lung fibrosis. Also, we find that inhibition or silencing of AKT augments oxidant-induced AEC mtDNA damage and apoptosis.ConclusionsOur data demonstrate a crucial role for AEC AKT signaling in mediating the mtDNA damage protective effects of Klotho. Given the importance of AEC aging and apoptosis in pulmonary fibrosis, we reason that Klotho/AKT axis is an innovative therapeutic target for preventing common lung diseases of aging (i.e. IPF, COPD, lung cancer, etc.) for which more effective management regimens are clearly needed.FundingNIH-RO1 ES020357-01A1 (DK) and VA Merit (DK).


Sign in / Sign up

Export Citation Format

Share Document