Cytotoxicity evaluation of Persica mouthwash on cultured human and mouse cell lines in the presence and absence of fetal calf serum.

Background and Aims: The effectiveness of an ideal antimicrobial agent depends on its ability to kill microbes while causing minimal toxicity to host cells. Several studies have been reported on the antimicrobial effects of chewing sticks (Salvadora persica) on oral bacteria. The purpose of this study was to evaluate the cytotoxic effects of Persica™ and chlorhexidine (CHX) mouthwashes on cultured human and mouse cell lines. Materials and Methods: This was an experimental study. The toxic effects of four dilutions of Persica™ and CHX mouthwashes on KB, Saos-2, J744 A1, and gingival fibroblast cells were evaluated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay. The effect of fetal calf serum (FCS) components on the cytotoxicity of these mouthwashes was also investigated. Statistical Analysis: Analysis of variance and the Kruskal-Wallis test were used to evaluate the results. Results: The results indicated that Persica™, at concentrations higher than 0.1%, exerted a very significant cytotoxic effect on all the cell lines (P < 0.01). CHX, at a concentration of 0.001%, exerted toxic effects only on gingival fibroblasts; concentrations higher than 0.001% were required to produce significant cell death in the other cell lines. At all the concentrations under study, both Persica™ and CHX exerted significantly greater cytotoxic effects in the absence of FCS than in its presence (i.e., in control culture medium). The toxicities of both mouthwashes were attenuated in the presence of FCS (10%). Conclusion: Our results indicate that both Persica™ and CHX mouthwashes are toxic to macrophage, epithelial, fibroblast, and osteoblast cells in a concentration-dependent manner.

Porphyromonas gingivalis decreases osteoblast proliferation through IL-6-RANKL/OPG and MMP-9/TIMPs pathways.

Background: Porphyromonas gingivalis, an important periodontal pathogen, is closely associated with inflammatory alveolar bone resorption. This bacterium exerts its pathogenic effect indirectly through multiple virulence factors, such as lipopolysaccharides, fimbriae, and proteases. Another possible pathogenic path may be through a direct interaction with the host's soft and hard tissues (e.g., alveolar bone), which could lead to periodontitis. Aims and Objectives: The aim of the present study was to investigate the direct effect of live and heat-inactivated P gingivalis on bone resorption, using an in vitro osteoblast culture model. Results: Optical microscopy and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide MTT assay revealed that live P gingivalis induced osteoblast detachment and reduced their proliferation. This effect was specific to live bacteria and was dependent on their concentration. Live P gingivalis increased IL-6 mRNA expression and protein production and downregulated RANKL and OPG mRNA expression. The effect of live P gingivalis on bone resorption was strengthened by an increase in MMP-9 expression and its activity. This increase was accompanied by an increase in TIMP-1 and TIMP-2 mRNA expression and protein production by osteoblasts infected with live P gingivalis. Conclusion: Overall, the results suggest that direct contact of P gingivalis with osteoblasts induces bone resorption through an inflammatory pathway that involves IL-6, RANKL/OPG, and MMP-9/TIMPs.

Effect of glutathione on arecanut treated normal human buccal fibroblast culture.

BACKGROUND: Experimental studies have shown arecanut to be a cytotoxic substance with mutagenic and carcinogenic potential. OBJECTIVE: The present study was undertaken to evaluate the effect of glutathione on arecanut treated human buccal fibroblast culture and its potential as a chemopreventive agent. MATERIALS AND METHODS: Fibroblast culture was done in Dulbecco's Modified Eagle's Medium MEM) supplemented with 10% Fetal Calf Serum (FCS) and antibiotic at 370C degrees in an atmosphere of 5% carbon di-oxide and 95% air. The fibroblast cells were subjected to different concentrations of aqueous extracts of raw and boiled arecanut. Fibroblasts were plated in two 24-well culture plates and in each plate, cells were dividt,ednto 2 groups; 600gg microml of reduced glutathione was added to the first group of cells; subsequently, aqueous extracts of raw and boiled arecanut at least and highest concentrations i.e., 20j. microml and 100lg microml were added to the first group of cells in the respective plates whereas the second group served as a control. The morphological alterations and cell survival were assayed at 24, 48, 72, and 96 hours. Results Morphologically, the initial (10 hours) attached fibroblast cells were converted from spheroidal shape towards hexagonal and finally to a fully extended spindle shaped configuration. The three morphological types of fibroblasts at 48 hours were F-I, F-II and F-III. Aqueous extract of raw arecanut exhibited significant cytotoxicity (p < .0 001) at all time periods studied, when compared against the control values of untreated fibroblasts. Addition of reduced glutathione to cultures showed a significant (p < 0. 001) reduction in cytotoxicity, as indicated by higher optical density values and morphological reversion to the spindle-shaped configuration. CoCONCLUSION:Addition of glutathione reduced the cytotoxic and morphological alterations of the fibroblasts treated with aqueous extracts of both raw and boiled arecanut.

Mycobacterium phlei as an oral immunomodulator with Newcastle disease vaccine.

Experiments were conducted in chickens to understand the effects of oral immunomodulation. Heat inactivated M phlei, a commensal Mycobacterium and a non-specific immunomodulator, was administered orally prior to live Newcastle disease F (ND F) strain vaccination. In experimental birds it lead to an enhanced cell mediated Immune response (CMI) against the vaccine. There was a reduction in the Haemagglutination inhibiting (HI) antibodies. However, it did not affect the protection against a virulent challenge, as the protection percentage was more or less same in vaccinated birds irrespective of the M.phlei administration. M. phlei administration could not enhance the immune response to inactivated ND F vaccine administered orally. The results indicate that M. phlei favours a CMI response to orally administered live ND F vaccine. It may be of potential use in enhancing CMI against vaccines and a cheaper alternative to costlier recombinant cytokines.

Triphenyl tetrazolium chloride (TTC) dye test for quick diagnosis of urinary tract infection.

We evaluate the triphenyl tetrazolium chloride (TTC) dye reduction test for quicker diagnosis of urinary tract infections for its sensitivity and reliability to detect significant bacteriuria. Of the 1400 urine samples tested 780 (55.7%) had significant bacteriuria. TTC dye test was positive in 678 (86.9%) of those with significant bacteriuria thereby showing its usefulness. The test is simple and cheap and can be carried out in field situations.