OBJECTIVETo test the survival of Staphylococcus aureus (S. aureus) inside lymphocyte that contributes to the pathogenesis of infection and possible anti-inflammatory and antioxidative effect of nanoconjugated vancomycin against in vivo S. aureus infection in a dose and duration dependent manner.

METHODS5×10(6) CFU/mL vancomycin-sensitive S. aureus (VSSA) and vancomycin-resistive S. aureus (VRSA) were challenged in Swiss male mice for 3 days, 5 days, 10 days and 15 days, respectively. Bacteremia and inflammatory parameters were observed to evaluate the duration for development of VSSA and VRSA infection. 100 mg/kg bw/day and 500 mg/kg bw/day nanoconjugated vancomycin were administrated to VSSA and VRSA infected group for 5 days. Bacteremia, inflammatory parameters and oxidative stress related parameters were tested to observe the effective dose of nanoconjugated vancomycin against VSSA and VRSA infection. Nanoconjugated vancomycin was treated at a dose of 100 mg/kg bw/day and 500 mg/kg bw/day, respectively, to VSSA and VRSA infected group for successive 5 days, 10 days and 15 days. Bacteremia, inflammatory parameters and oxidative stress related parameters were observed to assess the effective duration of nanoconjugated vancomycin against VSSA and VRSA infection.

RESULTSThe result revealed that in vivo VSSA and VRSA infection developed after 5 days of challenge by elevating the NO generation in lymphocyte and serum inflammatory markers. Administration with nanoconjugated vancomycin to VSSA and VRSA infected group at a dose of 100 mg/kg bw/day and 500 mg/kg bw/day, respectively, for successive 10 days eliminated bacterimia, decreased NO generation in lymphocyte, serum inflammatory markers and increased antioxidant enzyme status.

CONCLUSIONSThese findings suggest, in vivo challenge of VSSA and VRSA for 5 days can produce the highest degree of damage in lymphocyte which can be ameliorated by treatment with nanoconjugated vancomycin for 10 successive days.

Animals ; Anti-Bacterial Agents ; administration & dosage ; chemistry ; Bacteremia ; drug therapy ; immunology ; microbiology ; Drug Delivery Systems ; Humans ; Male ; Mice ; Nanoparticles ; chemistry ; Nitric Oxide ; immunology ; Staphylococcal Infections ; drug therapy ; immunology ; microbiology ; Staphylococcus aureus ; drug effects ; pathogenicity ; physiology ; Vancomycin ; administration & dosage ; chemistry ; Vancomycin Resistance

Objective: To compare the protective effects of chitosan-trypolyphosphate (CS-TPP) nanoparticle conjugated chloroquine(CQ) with effect of CQ alone on the reversal of splenic damages and induction of apoptosis. Methods: Different researches have been carried out to explore the potential role of chitosan based drug delivery system against parasitic diseases. After successive Plasmodium berghei NK65 parasiste infection by intraperitoneal injection in Swiss mice and subsequent parasite development, the ROS generation, anti-apoptotic and pro apoptotic protein levels in spleen were measured. To analyze caspases, flow cytometry study was performed with annexin V-FITC and with PI staining. Results: The results revealed that ROS mediated caspase 3 and 9 activation and the induction of apoptosis occurred during the parasitic infection. However, CS-TPP conjugated CQ was relatively better in reversing the splenic damage compared with similar effects of CQ alone. Conclusions: This study indicates that Plasmodium berghei NK65 induces apoptosis in the spleen. The study further shows that CS-TPP nanoparticles conjugation with CQ have positive influence on the recovery of damaged host's system towards maintenance of normal homeostasis, and this is shown to be selective to CS-TPP conjugated CQ treated animals only.