Protection of palmitic acid treatment in RAW264.7 cells and BALB/c mice during Brucella abortus 544 infection

Background@#We previously elucidated the protective mechanism of Korean red ginseng oil (RGO) against Brucella abortus infection, and our phytochemical analysis revealed that palmitic acid (PA) was an abundant component of RGO. Consequently, we investigated the contribution of PA against B. abortus. @*Objectives@#We aimed to investigate the efficacy of PA against B. abortus. infection using a murine cell line and a murine model. @*Methods@#Cell viability, bactericidal, internalization, and intracellular replication, western blot, nitric oxide (NO), and superoxide (O2 - ) analyses and flow cytometry were performed to determine the effects of PA on the progression of B. abortus. infection in macrophages. Flow cytometry for cytokine analysis of serum samples and bacterial counts from the spleens were performed to determine the effect of PA in a mouse model. @*Results@#PA did not affect the growth of B. abortus.. PA treatment in macrophages did not change B. abortus. uptake but it did attenuate the intracellular survivability of B. abortus.. Incubation of cells with PA resulted in a modest increase in sirtuin 1 (SIRT1) expression.Compared to control cells, reduced nitrite accumulation, augmented O2 - , and enhanced pro-inflammatory cytokine production were observed in PA-treated B. abortus.-infected cells.Mice orally treated with PA displayed a decreased serum interleukin-10 level and enhanced bacterial resistance. @*Conclusions@#Our results suggest that PA participates in the control of B. abortus. within murine macrophages, and the in vivo study results confirm its efficacy against the infection. However, further investigations are encouraged to completely characterize the mechanisms involved in the inhibition of B. abortus. infection by fatty acids.

Protection of palmitic acid treatment in RAW264.7 cells and BALB/c mice during Brucella abortus 544 infection

Background@#We previously elucidated the protective mechanism of Korean red ginseng oil (RGO) against Brucella abortus infection, and our phytochemical analysis revealed that palmitic acid (PA) was an abundant component of RGO. Consequently, we investigated the contribution of PA against B. abortus. @*Objectives@#We aimed to investigate the efficacy of PA against B. abortus. infection using a murine cell line and a murine model. @*Methods@#Cell viability, bactericidal, internalization, and intracellular replication, western blot, nitric oxide (NO), and superoxide (O2 - ) analyses and flow cytometry were performed to determine the effects of PA on the progression of B. abortus. infection in macrophages. Flow cytometry for cytokine analysis of serum samples and bacterial counts from the spleens were performed to determine the effect of PA in a mouse model. @*Results@#PA did not affect the growth of B. abortus.. PA treatment in macrophages did not change B. abortus. uptake but it did attenuate the intracellular survivability of B. abortus.. Incubation of cells with PA resulted in a modest increase in sirtuin 1 (SIRT1) expression.Compared to control cells, reduced nitrite accumulation, augmented O2 - , and enhanced pro-inflammatory cytokine production were observed in PA-treated B. abortus.-infected cells.Mice orally treated with PA displayed a decreased serum interleukin-10 level and enhanced bacterial resistance. @*Conclusions@#Our results suggest that PA participates in the control of B. abortus. within murine macrophages, and the in vivo study results confirm its efficacy against the infection. However, further investigations are encouraged to completely characterize the mechanisms involved in the inhibition of B. abortus. infection by fatty acids.

Inhibitory effect of red ginseng acidic polysaccharide from Korean red ginseng on phagocytic activity and intracellular replication of Brucella abortus in RAW 264.7 cells

Korean red ginseng (KRG) has long been used in traditional Korean and Oriental medicine. However, the anti-bacterial mechanism and therapeutic efficiency of KGR for intracellular Brucella infection are still unclear. In this study, the bactericidal activity of Korean red ginseng acidic polysaccharide (RGAP) on Brucella (B.) abortus and its cytotoxic effects on RAW 264.7 cells were evaluated. In addition, B. abortus internalization and intracellular replication in macrophages were investigated after RGAP treatment. RGAP-incubated cells displayed a marked reduction in the adherence, internalization and intracellular growth of B. abortus in macrophages. Furthermore, decreased F-actin fluorescence was observed relative to untreated B. abortus-infected cells. Western blot analysis of intracellular signaling proteins revealed reduced ERK, JNK and p38α phosphorylation levels in B. abortus-infected RGAP-treated cells compared to the control. Moreover, elevated co-localization of B. abortus-containing phagosomes with lysosome-associated membrane protein 1 (LAMP-1) were observed in RGAP-treated cells compared with the control. Overall, the results of this study suggest that RGAP can disrupt phagocytic activity of B. abortus via suppression of mitogen-activated protein kinases (MAPKs) signaling proteins ERK, JNK and p38 levels and inhibit intracellular replication of B. abortus by enhancing phagolysosome fusion, which may provide an alternative control of brucellosis.

Molecular cloning, purification and immunogenicity of recombinant Brucella abortus 544 malate dehydrogenase protein

The Brucella mdh gene was successfully cloned and expressed in E. coli. The purified recombinant malate dehydrogenase protein (rMDH) was reactive to Brucella-positive bovine serum in the early stage, but not reactive in the middle or late stage, and was reactive to Brucella-positive mouse serum in the late stage, but not in the early or middle stage of infection. In addition, rMDH did not react with Brucella-negative bovine or mouse sera. These results suggest that rMDH has the potential for use as a specific antigen in serological diagnosis for early detection of bovine brucellosis.

Molecular Detection of Giardia intestinalis from Stray Dogs in Animal Shelters of Gyeongsangbuk-do (Province) and Daejeon, Korea

Giardia is a major public health concern and considered as reemerging in industrialized countries. The present study investigated the prevalence of giardiosis in 202 sheltered dogs using PCR. The infection rate was 33.2% (67/202); Gyeongsangbuk-do and Daejeon showed 25.7% (39/152, P or =1 year of age which showed only 27.4% positive rate, 61.8% (P<0.001) of the total samples collected from young animals (<1 year of age) were positive for G. intestinalis. A significantly higher prevalence in symptomatic dogs (60.8%, P<0.0001) was observed than in asymptomatic dogs (23.8%). Furthermore, the analysis of nucleotide sequences of the samples revealed that G. intestinalis Assemblages A and C were found in the feces of dogs from Gyeongsangbuk-do and Daejeon. Since G. intestinalis Assemblage A has been known to infect humans, our results suggest that dogs can act as an important reservoir of giardiosis in Korea. Hence, hygienic management should be given to prevent possible transmission to humans.