ABSTRACT
Aims: Bacteria including Pseudomonas and T. thermophilus secretes rhamnose–containing glycolipid biosurfactants called rhamnolipids (RLs), known as bacterial virulence factors. The aim of this investigation was the evaluation of DNA damage induced on human lymphocytes by both RLs itself, secreted in a host organism by pathogens during a bacterial attack or symbiosis and in combination with the camptothecin (CPT), and on calf thymus DNA. Study Design: Human lymphocytes and calf thymus DNA were treated with isolated T. thermophilus RLs for studying DNA damage in vitro. Methodology: RLs DNA damaging action was evaluated by the Sister Chromatid Exchanges (SCEs) methodology, a method for estimating genotoxicity of human exposure to different chemicals or other mutagenic agents and by DNA electrophoretic mobility experiments. Results: RLs at concentrations of 100 and 150 μg/mL reveal significant toxicity. The highest concentration of 200 μg/mL reveals higher genotoxicity. The frequency of SCEs/cell was increased two times over the control level. When CPT, an antineoplastic drug with DNA damaging action, was tested together with RLs the genotoxic activity was reduced significantly (P<0.01) compared to the action caused by CPT itself. Sequential increase in the concentration of RLs results in the proportional reduction of Proliferation Rate Index (PRI) which is a cytostatic index. Also, Mitotic Index (MI), a cytotoxic index, was also significantly decreased at concentration of 200 μg/mL RLs. Addition of RLs in the same concentration together with CPT doesn’t affect the MI so much. Moreover, RLs are obviously capable for strong binding to plasmid or calf thymus DNA in vitro. Conclusion: RLs exert genotoxicity, cytotoxicity and cytostaticity in human lymphocytes and play probably a protective role for cells against CPT due to RLs’ detergent capability to enrobe CPT and DNA, providing a significant property that might support its possible involvement in DNA horizontal transfer phenomena.
ABSTRACT
Aims: There is little evidence concerning the effects of organophosphates in the liver of healthy individuals, and the existing researches come to contradictive results. In this study, we evaluated the influence of organophosphates (Dimethoate, Chlorpyrifos) in liver and renal function of healthy exposed workers, not experiencing symptoms of serious intoxication Study Design: Measure serum activity of the liver function monitoring enzymes SGPT, SGOT, γ-GT and ALP and serum concentration of the renal function indicative biomarkers urea and creatinine. Place and Duration of Study: Sample were collected in Health Care Greece of Iraklia Serres and analyzed in Department of Medical Laboratory Studies Alexander Technological Educational Institute of Thessaloniki. Methodology: Blood samples were collected from 112 individuals, randomly selected from villagers of N. Greece. 42 of them were organophosphates (OP) applicators aged less than 50 years old (mean age 37 years old) and 42 were OP applicators older than 50 years old (mean age 58 years old); while 28 individuals (13 of them were less than 50 years old and 15 older than 50 years) were not OP applicators and used as control groups. Results: A remarkable and statistically significant increase (P < 0.05) in the main liverfunction monitoring enzymes (SGOT, SGPT, γ-GT) was observed in exposed people compared to the control group. Increase in ALP values compared to not exposed individuals was not observed. Concerning the kidneys, data analysis shows that there is not any significant effect on their operation by the use of OP. Conclusion: The age of OP applicators and the time past between the application and the measure of blood serum seems to play an important role in the values of hepatic enzymes. While the renal indicators seemed not so much affected, as organophosphates are rapidly metabolized in human organism.