Therapeutic Efficacy of Ofloxacin and Ornidazole vs Mebatic: Toxicity Profile and Antioxidant Defense Study

Effect of iNOS inhibitor LNMMA along with antibiotics Chloramphenicol or Ofloxacin in murine peritoneal macrophages regulates S.aureus infection as well as inflammation: An in vitro study

Death due to sepsis by S. aureus is rapidly increasing because of their potent weaponries against macrophage mediated killing. Macrophages serve as intracellular reservoirs of S. aureus. Although significant resources have been invested during the last decade in new treatments for sepsis, only antibiotic therapy has failed to improve outcomes. Moreover the host pathogen interaction resulted in host cell death triggering inflammation. So, successful therapy requires amalgamation of therapies to delineate pathogen along with providing protection to host cell. With this idea, LNMMA, the iNOS inhibitor is used along with antibiotics Ofloxacin or Chloramphenicol on S. aureus infected mouse peritoneal macrophage. ROS like H₂O₂, O₂^- production has been measured. NO inhibition by iNOS inhibitor and antioxidant levels has been analysed. COX2, TLR2 and iNOS expression along with proinflammatory cytokine level was studied. It was found that the use of iNOS inhibitor LNMMA along with antibiotics not only enhances bacterial clearance but also decreases proinflammatory responses in Staphylococcus aureus infected macrophages. Inhibition of TLR2 as well as COX2 has also been found in combined treatment groups. The use of iNOS inhibitor LNMMA plus Ofloxacin or Chloramphenicol pretreatment enhanced bacterial clearance by increasing ROS. Decreases in NO protect the cell from harmful peroxynitril as well as inflammatory damage by changes in iNOS, COX2 activity along with reduced proinflammatory cytokines like TNFα, IFNγ, IL1-β etc. Changes in antioxidant level has been found. This in-vitro realm of augmented bacterial clearance and regulated inflammation may be considered as a novel and important therapeutic intervention.

The effect of sarafloxacin on Cu/ZnSOD structure and activity

The effect of sarafloxacin to Cu/ZnSOD was evaluated via investigating the change in Cu/ZnSOD structure and the structure basis activity upon sarafloxacin binding. Multi-spectroscopic methods, isothermal titration microcalorimetry (ITC) and molecular docking method were adopted in this study. Sarafloxacin binds to Cu/ZnSOD mainly through hydrophobic and hydrogen bond forces and tends to be saturated as the molar ratio of sarafloxacin to Cu/ZnSOD reaches 4. The binding changed the microenvironment around Tyr and the secondary structure of Cu/ZnSOD but did not affect the activity of Cu/ZnSOD. Molecular docking study revealed that sarafloxacin binds into a hydrophobic area with possibility to form hydrogen bonds with Tyr 108, Asp 25, Pro 100 and Ser 103 of Cu/ZnSOD. The binding area locates on the surface of β-barrel close to the second Greek key loop (GK2) and V-loop but far away from the active site and active site channel of Cu/ZnSOD. These promoted the understanding of the experiment phenomenons. The binding of sarafloxacin does not affect the activity of Cu/ZnSOD should attribute to the binding not to change the microenvironment of Cu/ZnSOD active site and active site channel.