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Acute phenanthrene toxicity to juvenile diploid and triploid African catfish (Clarias gariepinus): Molecular, biochemical, and histopathological alterations
2016
Karamī, ʻAlī | Romano, Nicholas | Hamzah, Hazilawati | Simpson, Stuart L. | Yap, Chee Kong
Information on the biological responses of polyploid animals towards environmental contaminants is scarce. This study aimed to compare reproductive axis-related gene expressions in the brain, plasma biochemical responses, and the liver and gill histopathological alterations in diploid and triploid full-sibling juvenile African catfish (Clarias gariepinus). Fish were exposed for 96 h to one of the two waterborne phenanthrene (Phe) concentrations [mean measured (SD): 6.2 (2.4) and 76 (4.2) μg/L]. In triploids, exposure to 76 μg/L Phe increased mRNA level of fushi tarazu-factor 1 (ftz-f1). Expression of tryptophan hydroxylase2 (tph2) was also elevated in both ploidies following the exposure to 76 μg/L Phe compared to the solvent control. In triploids, 76 μg/L Phe increased plasma alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) levels compared to the other Phe-exposed group. It also elevated lactate and glucose contents relative to the other groups. In diploids, however, biochemical biomarkers did not change. Phenanthrene exposures elevated glycogen contents and the prevalence of histopathological lesions in the liver and gills of both ploidies. This study showed substantial differences between diploids and triploids on biochemical and molecular biomarker responses, but similar histopathological alterations following acute Phe exposures.
Show more [+] Less [-]Alterations in juvenile diploid and triploid African catfish skin gelatin yield and amino acid composition: Effects of chlorpyrifos and butachlor exposures
2016
Karamī, ʻAlī | Karbalaei, Samaneh | Zad Bagher, Fariba | Ismail, Amin | Simpson, Stuart L. | Courtenay, Simon C.
Skin is a major by-product of the fisheries and aquaculture industries and is a valuable source of gelatin. This study examined the effect of triploidization on gelatin yield and proximate composition of the skin of African catfish (Clarias gariepinus). We further investigated the effects of two commonly used pesticides, chlorpyrifos (CPF) and butachlor (BUC), on the skin gelatin yield and amino acid composition in juvenile full-sibling diploid and triploid African catfish. In two separate experiments, diploid and triploid C. gariepinus were exposed for 21 days to graded CPF [mean measured: 10, 16, or 31 μg/L] or BUC concentrations [Mean measured: 22, 44, or 60 μg/L]. No differences in skin gelatin yield, amino acid or proximate compositions were observed between diploid and triploid control groups. None of the pesticide treatments affected the measured parameters in diploid fish. In triploids, however, gelatin yield was affected by CPF treatments while amino acid composition remained unchanged. Butachlor treatments did not alter any of the measured variables in triploid fish. To our knowledge, this study is the first to investigate changes in the skin gelatin yield and amino acid composition in any animal as a response to polyploidization and/or contaminant exposure.
Show more [+] Less [-]Cytotoxic and genotoxic effects of clopyralid herbicide on Allium cepa roots
2021
Amaç, Eslem | Liman, Recep
Clopyralid is one of the synthetic pyridine-carboxylate auxin herbicides and used to control perennial and annual broadleaf weeds in wheat, sugar beets, canola, etc. In this study, dose-dependent cytotoxicity and genotoxicity of clopyralid at different concentrations (25, 50, and 100 μg/mL) have been evaluated on the Allium cepa roots. The evaluation has been performed at macroscopic (root growth) and microscopic levels [mitotic index (MI), chromosome aberrations (CAs) in ana-telophase cells, and DNA damage] using root growth inhibition, Allium ana-telophase, and comet tests. The percentage of root growth inhibition and concentration of reducing root growth by 50% (EC₅₀) of clopyralid were determined compared with the negative control by using various concentrations of clopyralid (6.25–1000 μg/L). The 96 h EC₅₀ of clopyralid was recorded as 50 μg/L. The gradual decrease in root growth and the MI reveals the cytotoxic effects of clopyralid. All the tested concentrations of clopyralid induced total CAs (polyploidy, stickiness, anaphase bridges, chromosome laggards, and disturbed ana-telophase) and DNA damage dose and time dependently. These results confirm the cytotoxic and genotoxic effects of clopyralid on non-target organism.
Show more [+] Less [-]Assessment of anticytotoxic effect of lichen Cladonia foliacae extract on Allium cepa root tips
2018
The aim of this study is to investigate the protective effect of lichen Cladonia foliacae (Huds.) (CF) on hydrogen peroxide (H₂O₂)-induced toxicity through cell death, chromosome aberrations, mitotic index, oxidative stress parameters, and DNA damage in a Allium cepa root meristematic cells. Any chemical was not given for control group. Two doses of H₂O₂ (3 and 7%) were given to the roots for 1 h and the root tips were treated with CF water extract (50 and 100 μL) with increasing times for treatment groups. The roots were taken from control and treatment groups, and mitotic index, cell death, and chromosome aberrations were performed by light microscope. Changing antioxidant capacity of roots was revealed by FRAP and TEAC assay. Also, DNA damage was measured by comet assay and RAPD-PCR technique. Chromosome aberration values were obtained with increasing concentrations with longer treatment times, such as chromosome bridge, vagrant, and polyploidy in both groups. Increasing exposure doses of H₂O₂ caused decreasing mitotic index values at 72 h. TEAC and FRAP assay demonstrated that roots’ capacity of antioxidant was altered by increasing concentrations of H₂O₂. The tail DNA% and tail length significantly increased in all exposure times when compared to control group. Three and seven percent of H₂O₂ caused the genotoxic effect on genetic material at 72 h according to RAPD-PCR technique. Increasing the doses of H₂O₂ resulted in increased toxicity to all studied parameters of A. cepa, but CF extract altered all changing parameters of A. cepa root cell. The H₂O₂ tested in this study have cytotoxic and mutagenic potential, but extract of CF was protective against H₂O₂ caused toxicological changes. But, it did not protect completely in the A. cepa root meristematic cells.
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