Lactobacillus species in the female genital tract are thought to act as a barrier to infection. Several studies have demonstrated that lactobacilli can adhere to vaginal epithelial cells. However, little is known about how the adherence of lactobacilli to vaginal epithelial cells affects the acidity, cell viability, or proliferation of the lactobacilli themselves or those of vaginal epithelial cells. Lactobacillus acidophilus was co-cultured with immortalized human vaginal epithelial cells (MS74 cell line), and the growth of L. acidophilus and the acidity of the culture medium were measured. MS74 cell density and viability were also assessed by counting cell numbers and observing the cell attachment state. L. acidophilus showed exponential growth for the first 6 hr until 9 hr, and the pH was maintained close to 4.0-5.0 at 24 hr after culture, consistent with previous studies. The growth curve of L. acidophilus or the pH values were relatively unaffected by co-culture with MS74 cells, confirming that L. acidophilus maintains a low pH in the presence of MS74 cells. This co-culture model could therefore potentially be used to mimic vaginal conditions for future in vitro studies. On the other hand, MS74 cells co-cultured with L. acidophilus more firmly attached to the culture plate, and a higher number of cells were present compared to cells cultured in the absence of L. acidophilus. These results indicate that L. acidophilus increases MS74 cell proliferation and viability, suggesting that lactobacilli may contribute to the healthy environment for vaginal epithelial cells.
Cell Adhesion ; Cell Line ; Cell Survival ; Coculture Techniques ; Culture Media/chemistry ; Epithelial Cells/*microbiology/*physiology ; Female ; Humans ; Hydrogen-Ion Concentration ; Lactobacillus acidophilus/growth & development/metabolism/*physiology ; Time Factors

PURPOSE: Recent studies have demonstrated that probiotics are effective in the management of allergic diseases, but there have been few reports about their preventive effects in asthma. We examined the effects of Lactobacillus acidophilus (LA) and its mechanism in the primary prevention of asthma. METHODS: Before allergen sensitization, newborn Balb/c mice orally received 1x10(9) colony forming unit (CFU) LA per day every 2 days for consecutive 4 weeks starting from birth. After ovalbumin sensitization and challenge from day 36, airway hyperresponsiveness (AHR) to methacholine, influx of inflammatory cells to the lung, serum total IgE levels, cytokine levels in the supernatant of splenocytes culture, and expression of FoxP3 mRNA in the peribronchial lymph nodes were assessed. RESULTS: The AHR showed a tendency to decrease in LA group, however, there was no statistical significance. The eosinophil counts in bronchoalveolar lavage fluid and serum total IgE were significantly reduced in LA group compared with asthma control group. LA effectively induced IFN-gamma secretion and inhibited IL-4, IL-5 and TGF-beta1 secretion compared with asthma control group. The expression of FoxP3 mRNA in peribronchial lymph nodes did not show any difference between LA and asthma control group. CONCLUSION: Oral LA administration in murine model of asthma attenuated AHR and significantly suppressed eosinophilic inflammation in the airway. These effects of LA were mediated by suppressing Th2 immune response and enhancing Th1 immune response. The results may suggest the possible role of LA in the primary prevention of asthma.
Animals ; Asthma ; Bronchoalveolar Lavage Fluid ; Eosinophils ; Humans ; Immunoglobulin E ; Infant, Newborn ; Inflammation ; Interleukin-4 ; Interleukin-5 ; Lactobacillus ; Lactobacillus acidophilus ; Lung ; Lymph Nodes ; Methacholine Chloride ; Mice ; Ovalbumin ; Parturition ; Primary Prevention ; Probiotics ; RNA, Messenger ; Stem Cells ; Transforming Growth Factor beta1

BACKGROUNDCecropin-XJ belongs to cecropin-B, which is the most potent antibacterial peptide found naturally. The aim of this study was to investigate the effects of cecropin-XJ on growth and adherence of oral cariogenic bacteria.

METHODSFour oral cariogenic bacteria (Streptococcus mutans, Lactobacillus acidophilus, Actinomyces viscosus and Actinomyces naeslundii) were chosen for this experiment. The minimal inhibitory concentrations (MICs) and reductive percent of bacterial growth were used to assay the antibacterial activity of cecropin-XJ. Mammalian cytotoxicity of cecropin-XJ was tested with human periodontal membrane fibroblasts by tetrazolium (MTT) colorimetric assay. The bacterial morphological changes induced by cecropin-XJ were examined on scanning electron microscope (SEM). The influence of cecropin-XJ on bacterial adhesion to saliva-coated hydroxyapatite (S-HA) was measured by scintillation counting.

RESULTSThe MICs of cecropin-XJ for inhibition of the growth of four bacteria ranged from 4.0 to 42.8 micromol/L with the highest susceptible to A. naeslundii and the lowest susceptible to L. acidophilus. At pH 6.8, 5.5 and 8.2, 1/2 MIC of cecropin-XJ reduced the number of viable bacteria by 40.9%, 67.8% and 32.8% for S. mutans and by 28.1%, 57.2% and 37.9% for L. acidophilus. The activities against S. mutans and L. acidophilus increased at pH 5.5 compared with pH 6.8 (P < 0.01, respectively). In present of 50% saliva, 1/2 MIC of the peptide decreased the direct count of viable cells by 29.2% and 14.4% for S. mutans and L. acidophilus, respectively (P < 0.01 and P > 0.05, respectively), whereas almost no reduction counts were detected in the presence of 20% serum for both bacteria (P > 0.05, respectively). Mammalian cytotoxicity of cecropin-XJ from 1.0 to 100 micromol/L exhibited no cytotoxicity against human periodontal membrane fibroblasts (P > 0.05). Bacterial morphological changes induced by MIC of cecropin-XJ examined on SEM showed cell surface disruption. Furthermore, the ability of A. naeslundii adhesion to S-HA decreased significantly with MIC of cecropin-XJ for 10 and 20 minutes (P = 0.001 and 0.000, respectively), and S. mutans, A. viscosus to S-HA decreased significantly with MIC of cecropin-XJ for 20 minutes (P = 0.000, respectively).

CONCLUSIONSCecropin-XJ exhibited bactericidal action against cariogenic pathogens, and the antibacterial activity enhanced in the acid environment. The results also demonstrate that cecropin-XJ prevents S. mutans and actinomyces adsorption to S-HA. These findings suggest that Cecropin-XJ may have potential to prevent caries.

Actinomyces viscosus ; drug effects ; Anti-Infective Agents ; pharmacology ; Bacteria ; drug effects ; growth & development ; Bacterial Adhesion ; drug effects ; Base Sequence ; Dental Caries ; microbiology ; Humans ; Insect Proteins ; pharmacology ; Lactobacillus acidophilus ; drug effects ; Microbial Sensitivity Tests ; Molecular Sequence Data ; Streptococcus mutans ; drug effects

Rhynchosia volubilis Lour has been a major drug in a folk prescription for contraception in China, whereas its mechanism remains unknown. Its antifertility effects on male mice and antimicrobial activities on sexually transmitted infection (STI) pathogens were previously reported. This study was undertaken to develop the n-Butanol extract of Rhynchosia volubilis Lour (BERVL) as a spermicidal agent with STI prevention. The spermicidal activities of BERVL with different doses were assessed using selected high-motile sperms of normal human semen samples, and their inhibitory effects on Lactobacillus acidophilus were determined. The mechanism of the spermicidal activity was explored by aqueous Eosin Y and Hoechst 33342/PI staining. The results showed spermicidal activities and inhibitory effects of BERVL on Lactobacillus acidophilus were dose-dependent. Dose of 90 mg/mL BERVL terminated all progressive sperm motility within 2 min, and had slight inhibitory effect on Lactobacillus acidophilus, suggesting it was an effective and safe dose for contraception use. About 80% sperms exposed to BERVL displayed changes consistent with high permeability of head membrane. It is concluded that BERVL as spermicide has advantages over N-9 with strong ability to instantaneously kill human sperm and possesses light inhibitory effect on Lactobacillus acidophilus.
1-Butanol ; chemistry ; Adult ; Dose-Response Relationship, Drug ; Fabaceae ; chemistry ; Humans ; Lactobacillus acidophilus ; drug effects ; growth & development ; Male ; Plant Extracts ; chemistry ; pharmacology ; Sperm Motility ; drug effects ; Spermatocidal Agents ; chemistry ; pharmacology ; Spermatozoa ; drug effects ; physiology ; Young Adult