Synovial Cell Migration is Associated with B Cell Activating Factor Expression Increased by TNFα or Decreased by KR33426

Fibroblast-like synoviocytes (FLS) play a crucial role in initiating rheumatoid arthritis. B-cell activating factor (BAFF) plays a role in FLS survival as well as in B cell maturation and maintenance. Here, we investigated whether tumor necrosis factor (TNF)-α-induced BAFF expression controls FLS migration and whether BAFF expression in FLS could be regulated by KR33426 which is the inhibitor of BAFF binding to BAFF receptors (BAFF-R) by using MH7A synovial cells transfected with the SV40 T antigen. More TNF-α-treated cells migrated compared to the control. TNF-α increased BAFF expression in FLS, significantly. FLS migration was inhibited by the transfection with BAFF-siRNA. KR33426 also inhibited BAFF expression increased by TNF-α treatment in FLS as judged by western blotting, PCR, and transcriptional activity assay. Kinases including JNK, p38 and Erk were activated by TNF-α treatment. While JNK and p38 were inhibited by KR33426 treatment, no changes in Erk were observed. Transcription factors including p65, c-Fos, CREB and SP1 were enhanced by TNF-α treatment. Among them, c-Fos was inhibited by KR33426 treatment.Small interference(si)-RNA of c-fos decreased BAFF transcriptional activity. FLS migration induced by TNF-α was inhibited by the transfection with BAFF-siRNA. KR33426 increased Twist, Snail, Cadherin-11 and N-Cadherin. In contrast, KR33426 decreased E-cadherin and TNF-α-enhanced CCL2. Taken together, our results demonstrate that synovial cell migration via CCL2 expression could be regulated by BAFF expression which is decreased by KR33426 and c-Fos-siRNA. It suggests for the first time that the role of BAFF-siRNA on FLS migration might be matched in the effect of KR33426 on BAFF expression.

Curcumin-Induced Autophagy Augments Its Antitumor Effect against A172 Human Glioblastoma Cells

Glioblastoma is the most aggressive common brain tumor in adults. Curcumin, from Curcuma longa, is an effective antitumor agent. Although the same proteins control both autophagy and cell death, the molecular connections between them are complicated and autophagy may promote or inhibit cell death. We investigated whether curcumin affects autophagy, which regulates curcumin-mediated tumor cell death in A172 human glioblastoma cells. When A172 cells were incubated with 10 μM curcumin, autophagy increased in a time-dependent manner. Curcumin-induced cell death was reduced by co-incubation with the autophagy inhibitors 3-methyladenine (3-MA), hydroxychloroquine (HCQ), and LY294002. Curcumin-induced cell death was also inhibited by co-incubation with rapamycin, an autophagy inducer. When cells were incubated under serum-deprived medium, LC3-II amount was increased but the basal level of cell viability was reduced, leading to the inhibition of curcumin-induced cell death. Cell death was decreased by inhibiting curcumin-induced autophagy using small interference RNA (siRNA) of Atg5 or Beclin1. Therefore, curcumin-mediated tumor cell death is promoted by curcumin-induced autophagy, but not by an increase in the basal level of autophagy in rapamycin-treated or serum-deprived conditions. This suggests that the antitumor effects of curcumin are influenced differently by curcumin-induced autophagy and the prerequisite basal level of autophagy in cancer cells.

Immunoregulation of Murine Immunocytes to Bifidobacteria Strain Isolated from Feces of Healthy Korean Children: IL-10 Release and Proportional Change of CD4+CD25+ Cells

Bifidobacteria is one of the prototypes of probiotics bacteria, normally inhabitating the intestinal tract of humans. To search for a potent immunoregulatory Bifidobacteria strain, we screened the Bifidobacteria strains isolated from the feces of healthy Korean children. The mRNA or protein expression of an anti-inflammatory cytokine, IL-10, from mouse macrophages stimulated with live Bifidobacteria was examined. Of tested strains, Bifidobacteria A28 induced the highest IL-10 gene expression of murine macrophages. To probe immunoregulatory activity of the selected strain on the mice, we evaluated the proportional changes of CD4+CD25+ surface marker in the murine splenocytes. Flow cytometric analysis showed that the overall percentages of CD4+CD25+ cells in A28-treated splenocytes were higher than those of untreated splenocytes. In parallel, IL-10 release from A28-treated mouse peritoneal macrophages and splenocytes was significantly higher than that of untreated control cells. Collectively, the Bifidobacteria A28 strain isolated from the feces of healthy Korean children augments the mRNA or protein expression of IL-10 release from mouse peritoneal macrophages as well as the proportion of CD4+CD25+ cells of naive splenocytes. These provide in vitro scientific clues that Bifidobacteria A28 might be usable for anti-inflammatory disease such as inflammatory bowel disease (IBD).

Salmonella enterica Serovar London Infections Associated with Consumption of Infant Formula

Epidemiologic studies were conducted on 31 cases of Salmonella group E infection detected in 2000 through a laboratory-based pathogen surveillance in Gangwon Province, Korea. Data were collected on the environmental exposures and the patients' foods, including the brand (s) of milk consumed before the onset of diarrhea. The patients' medical records were also reviewed. All of the patients were infants under 10 months of age except one 7-year old child. Surprisingly, all of the infants were fed with infant formulas from Company A, although two infants were fed with infant formulas from both Company A and Company B. Antimicrobial susceptibility test and pulsed-field gel electrophoresis (PFGE) were performed in 25 out of 31 isolates from the patients and in 1 isolate from an opened packet of infant formula collected from the home of an infected infant. All of the 26 isolates were Salmonella enterica serovar London. They showed a single PFGE pattern, and all of the isolates were susceptible to the 18 antibiotics tested. The causative agent of the salmonella outbreaks in the Gangwon Province and its surrounding areas was Salmonella London, and the highly likely source of the infection was infant formula from Company A.