Prostaglandin E release from human monocytes treated with lipopolysaccharides isolated from Bacteroides intermedius and Salmonella typhimurium: potentiation by gamma interferon

Maraj

1998

Infect Immun

Bacterial hydroxy fatty acids and alpha-hydroxy fatty acids have been demonstrated in complex lipid extracts of subgingival plaque and gingival tissue. However, little is known about the relationship between these hydroxy fatty acids in plaque and gingival tissues or the significance of these complex lipids in promoting inflammatory periodontal disease. The present study determined the percentages of ester-linked and amide-linked hydroxy fatty acids in complex lipids recovered from plaque and gingival tissue samples and the relationship between bacterial hydroxy fatty acids and alpha-hydroxy fatty acids in the lipid extracts. To evaluate a potential role for these hydroxy fatty acids in inflammatory periodontal disease, gingival tissue samples were examined for a relationship between prostaglandin E2 (PGE2) and hydroxy fatty acids recovered in gingival lipid. This investigation demonstrated that alpha-hydroxy fatty acids are only ester linked in plaque lipids but are largely amide linked in gingival tissue lipids. Furthermore, the level of alpha-hydroxy fatty acid in gingival lipid is directly related to the level of the bacterial hydroxy fatty acid 3-OHiso-branched C17:0 (3-OH iC17:0) in the same lipid extract. However, the relationship between hydroxy fatty acids in gingival lipids does not parallel the fatty acid relationship observed in plaque lipids. Finally, alpha-hydroxy fatty acid levels in gingival tissue lipids correlate directly with the recovery of PGE2 in the same tissue samples. These results demonstrate that alpha-hydroxy fatty acid levels in gingival lipids are directly related to both 3-OH iC17:0 bacterial lipid levels and PGE2 levels. These results indicate that in periodontal tissues there are unusual host-parasite interactions involving penetration of bacterial lipid in association with an altered gingival lipid metabolism and prostaglandin synthesis.

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Relationship between Hydroxy Fatty Acids and Prostaglandin E₂in Gingival Tissue

Maraj

1998

Infect Immun

“…Frozen samples of oral strains of P. gingivalis obtained from gingivitis and periodontitis sites (generously provided by W. E. C. Moore) were also analyzed. Bacterial LPS isolates from P. intermedia and P. gingivalis were prepared as described previously (15). Bacterial samples and bacterial LPS isolates were analyzed for hydroxy fatty acid content as described below.…”

Section: Methodsmentioning

confidence: 99%

Distribution of 3-hydroxy iC17:0 in subgingival plaque and gingival tissue samples: relationship to adult periodontitis

1994

Infect Immun

Self Cite

Gram-negative organisms incorporate hydroxy fatty acids into the lipid A moiety of lipopolysaccharide (LPS), and in the case of some members of the family Enterobacteriaceae, hydroxy fatty acids are incorporated exclusively into lipid A. However, a limited number of Bacteroides species have been shown to incorporate several classes of 3-hydroxy fatty acids, particularly 3-hydroxy iC17:0, into constitutive lipids as well as LPS. The present study examined the distribution of hydroxy fatty acids in two periodontal pathogens, Prevotella intermedia and Porphyromonas gingivalis, by employing a phospholipid extraction procedure (E. G. Bligh and W. J. Dyer, Can. J. Biochem. Physiol. 37:911-917, 1959) which partitioned constitutive lipids into the organic solvent phase and LPS into the aqueous phase. The distribution of hydroxy fatty acids within organic solvent and aqueous extracts of these bacterial species was then compared with the distribution in subgingival plaque samples isolated from either gingivitis or severe periodontitis sites as well as the distribution in gingival tissue samples. The organic solvent and aqueous extracts were hydrolyzed under strong alkaline conditions, and the free fatty acids were treated to form pentafluorobenzyl-ester, trimethylsilyl-ether derivatives. Hydroxy fatty acid levels were quantified by using gas chromatography-negative-ion chemical ionization-mass spectrometry. By using this approach, the mean values of the 3-hydroxy iC17:0 recovered within organic solvent extracts of P. gingivalis strains ranged from 56 to 63% of total 3-hydroxy iC17:0. Substantially less 3-hydroxy iC17:0 (< 5%) was recovered in organic solvent extracts of P. intermedia. By comparison, 75% of the 3-hydroxy iC17:0 in periodontitis subgingival plaque samples was recovered in organic solvent extracts, while only 43% of the 3-hydroxy iC17:0 in gingivitis plaque samples from the same patients was recovered in organic solvent extracts. However, 3-hydroxy iC17:0 was recovered essentially only in organic solvent extracts of both healthy or mildly inflamed and periodontitis gingival tissue samples. The preferential recovery of 3-hydroxy iC17:0 in tissue lipids indicates that gingival tissues do not harbor significant levels of subgingival plaque organisms which contain 3-hydroxy iC17:0. Furthermore, these results indicate that LPS from these organisms is not prevalent in gingival tissues. Finally, these results indicate either selective penetration of certain bacterial lipids into gingival tissues or that 3-hydroxy iC17:0 is metabolically transferred from bacterial lipids into gingival tissue lipids.

“…All derivatizing agents were obtained from Pierce Chemical Corp. (Rockford, IL, USA). The dried fatty acid samples were dissolved in acetonitrile (30 ml) and treated with 35% penta¯uorobenzyl bromide in acetonitrile (10 ml) and diisopropylethylamine (10 ml) (18). The solution was heated for 20 minutes at 40³C and evaporated to dryness under N 2 gas.…”

Section: Synthesis Of Fatty Acid Derivatives and Gc-ms Analysismentioning

confidence: 99%

Prostaglandin E₂ secretion from gingival fibroblasts treated with interleukin‐1β: effects of lipid extracts from Porphyromonas gingivalis or calculus

J of Periodontal Research

Levinbook

Shnaydman

et al. 2001

Complex lipids of Porphyromonas gingivalis have been identified in lipid extracts from calculus-contaminated root surfaces and in diseased gingival tissues. However, little is known about the biological effects of these complex lipids on host cells. The purpose of this study was to evaluate the effects of P. gingivalis or calculus lipids on prostaglandin secretion from gingival fibroblasts. Lipids were extracted from paired subgingival plaque and teeth samples, and calculus-contaminated root surfaces before and after scaling and root planing, in order to determine the relevant levels of lipid extracts for the treatment of gingival fibroblasts in culture. Primary cultures of gingival fibroblasts were exposed to lipid extracts from either P. gingivalis or calculus/teeth for a period of 7 days. Control and lipid-treated cultures were exposed to human recombinant interleukin-1beta for 48 h and prostaglandin secretion from interleukin-1beta-treated fibroblasts was compared with control and lipid-treated fibroblasts without interleukin-1beta treatment. These experiments demonstrated that P. gingivalis lipids or calculus-tooth lipids potentiate interleukin-1beta-mediated prostaglandin secretory responses from gingival fibroblasts. Additionally, P. gingivalis or calculus-tooth lipid extracts were readily taken up by gingival fibroblasts as measured by bacterial fatty acid recovery in lipid extracts of cultured fibroblasts. These results indicate that bacterial lipid penetration into gingival tissues in combination with a chronic inflammatory response may substantially potentiate prostaglandin secretion from gingival fibroblasts, thereby promoting tissue destructive processes associated with adult periodontitis.