scholarly journals Involvement of Reactive Oxygen Species in the Action of Ciprofloxacin against Escherichia coli

2006 ◽  
Vol 50 (3) ◽  
pp. 949-954 ◽  
Author(s):  
M. Goswami ◽  
S. H. Mangoli ◽  
N. Jawali

ABSTRACT Ciprofloxacin is an important and commonly used member of the fluoroquinolone group of antibiotics. Ciprofloxacin inhibits DNA topoisomerase II and DNA topoisomerase IV activities, eventually leading to bacterial cell death. In addition, an increase of reactive oxygen species in the bacterial cells in response to ciprofloxacin has been shown. We investigated the role of reactive oxygen species in the antibacterial action of ciprofloxacin by studying the effects of different antioxidant compounds on ciprofloxacin susceptibility of Escherichia coli. Among the antioxidants checked, glutathione and ascorbic acid provided substantial protection against ciprofloxacin. The involvement of superoxide anion (O2 −) and hydrogen peroxide (H2O2) in the antibacterial action of ciprofloxacin was analyzed using superoxide dismutase, catalase, and alkyl hydroperoxide reductase knockout strains of E. coli. The effects of multicopy sod genes on ciprofloxacin susceptibility of E. coli were also analyzed. On the basis of our results, we conclude that O2 − and H2O2 may be involved in antibacterial action of ciprofloxacin. Our findings that glutathione gave protection against other fluoroquinolones and not against nonfluoroquinolone antibiotics imply that reactive oxygen species may have a similar role in the antibacterial action of all these fluoroquinolones and that glutathione-mediated protection is not a general phenomenon but specific to fluoroquinolones. These observations are of significance, as fluoroquinolones are important antibiotics with immense therapeutic value, and the effectiveness of treatment by these drugs may be affected by dietary intake and cellular levels of these antioxidants.

2007 ◽  
Vol 51 (3) ◽  
pp. 1119-1122 ◽  
Author(s):  
Manish Goswami ◽  
Suhas H. Mangoli ◽  
Narendra Jawali

ABSTRACT We examined the effects of antioxidants and the role of reactive oxygen species (ROS) on the antibacterial action of aminoglycosides in Escherichia coli. We concluded that reduced streptomycin sensitivity in the presence of glutathione and ascorbic acid is not due to the antioxidant-mediated scavenging of ROS.


2010 ◽  
Vol 15 (2) ◽  
pp. 143-149
Author(s):  
Sukarjati Sukarjati ◽  
Doddy M. Soebady ◽  
Aucky Hinting ◽  
Sudjarwo Sudjarwo

In humans, male genital tract infection has been recognized as one of the causes of infertility. Indicators of the occurrence of genital tract infection are the presence of bacteria during semen culture (bacteriospermia) and the finding of leucocyte of more than 1 million/ml semen (leucotytospermia). Escherichia coli (E. coli) is the most common cause of prostatitis and epididymitis. The objective of this study was to determine the effects of E. coli and granulocytes on Reactive Oxygen Species (ROS) level in vitro. This study comprised of two experiments. In the experiment 1, sperm was incubated with E. coli, and the experiment 2, the sperm was incubated with granulocyte. In those experiments, ROS levels were observed. Spermatozoa were obtained from donor with normal spermatozoa according to WHO (1999). Escherichia coli was obtained by culturing the semen of infertile males. Granulocytes were obtained from donors’ blood. Sperm preparation was made by using Percoll gradient column method. Granulocyte isolation used Histopaque 1077 and 1119. ROS level was detected by means of chemiluminescence method with beta counter device. The result of this study showed that in vitro E. coli had the effect on ROS level, both stimulated by peroxidase (p = 0.000) and PMA (p = 0.006). Granulocyte had effect on ROS level. In peroxidase-stimulated ROS level, there was the effect between spermatozoa and granulocyte-incubated sperm (p = 0.000), granulocyte-incubated sperm and granulocyte (p = 0.002), and sperm and granulocyte (p = 0.000). In PMA-stimulated ROS level, there was effect between sperm and granulocyte-incubated sperm (p = 0.000), sperm and granulocyte (p = 0.000), granulocyte-incubated sperm and granulocyte (p = 0.000). In conclusion, under in vitro experiment, sperm incubated with E. coli and sperm incubated with granulocyte had the effect on the level of the ROS.


Author(s):  
Anahita Rezaeiroshan ◽  
Majid Saeedi ◽  
Katayoun Morteza-Semnani ◽  
Jafar Akbari ◽  
Akbar Hedayatizadeh-Omran ◽  
...  

Abstract Purposes Reactive oxygen species production is harmful to human’s health. The presence of antioxidants in the body may help to diminish reactive oxygen species. Trans-ferulic acid is a good antioxidant, but its low water solubility excludes its utilization. The study aims to explore whether a vesicular drug delivery could be a way to overcome the poor absorption of trans-ferulic acid hence improving its antimicrobial efficiency and antioxidant effect. Methods Niosomal vesicles containing the drug were prepared by film hydration method. The obtained vesicles were investigated in terms of morphology, size, entrapment efficiency, release behavior, cellular cytotoxicity, antioxidant, cellular protection study, and antimicrobial evaluations. Results The optimized niosomal formulation had a particle size of 158.7 nm and entrapment efficiency of 21.64%. The results showed that the optimized formulation containing 25 μM of trans-ferulic acid could enhance the viability of human foreskin fibroblast HFF cell line against reactive oxygen species production. The minimum effective dose of the plain drug and the niosomal formulation against Staphylococcus aurous (ATCC 29213) was 750 µg/mL and 375 µg/mL, respectively, and for Escherichia coli (ATCC 25922), it was 750 µg/mL and 187/5 µg/mL, respectively. The formulation could also improve the minimum bactericidal concentration of the drug in Staphylococcus aurous, Escherichia coli, and Acinobacter baumannii (ATCC 19606). Conclusion These results revealed an improvement in both antibacterial and antioxidant effects of the drug in the niosomal formulation.


1996 ◽  
Vol 40 (3) ◽  
pp. 710-714 ◽  
Author(s):  
Y Kumagai ◽  
J I Kato ◽  
K Hoshino ◽  
T Akasaka ◽  
K Sato ◽  
...  

Escherichia coli quinolone-resistant strains with mutations of the parC gene, which codes for a subunit of topoisomerase IV, were isolated from a quinolone-resistant gyrA mutant of DNA gyrase. Quinolone-resistant parC mutants were also identified among the quinolone-resistant clinical strains. The parC mutants became susceptible to quinolones by introduction of a parC+ plasmid. Introduction of the multicopy plasmids carrying the quinolone-resistant parC mutant gene resulted in an increase in MICs of quinolones for the parC+ and quinolone-resistant gyrA strain. Nucleotide sequences of the quinolone-resistant parC mutant genes were determined, and missense mutations at position Gly-78, Ser-80, or Glu-84, corresponding to those in the quinolone-resistance-determining region of DNA gyrase, were identified. These results indicate that topoisomerase IV is a target of quinolones in E. coli and suggest that the susceptibility of E. coli cells to quinolones is determined by sensitivity of the targets, DNA gyrase and topoisomerase IV.


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