Preventive effects of the novel antimicrobial peptide Nal-P-113 in a rat Periodontitis model by limiting the growth of Porphyromonas gingivalis and modulating IL-1ß and TNF-α production.

BACKGROUND: P-113 (AKRHHGYKRKFH-NH2) is a 12-amino-acid histidine-rich peptide derived from histatin 5 that is highly degradable in high salt concentrations and biological fluids such as serum, plasma and saliva. Nal-P-113, a novel antimicrobial peptide whose histidine residues are replaced by the bulky amino acids ß-naphthylalanine, causes the antimicrobial peptide to retain its bactericidal activity even in physiological environments. This study evaluated the effect of the novel antimicrobial peptide Nal-P-113 in a rat periodontitis model and the mechanisms of action of Nal-P-113 for suppressing periodontitis. METHODS: Periodontitis was induced in mandibular first molars in rats receiving a ligature and infected with Porphyromonas gingivalis. Animals were randomly divided into six groups: a, P. gingivalis W83 alone; b, P. gingivalis W83 with 6.25 µg/mL of Nal-P-113; c, P. gingivalis W83 with 25 µg/mL of Nal-P-113; d, P. gingivalis W83 with 100 µg/mL of Nal-P-113; e, P. gingivalis W83 with 400 µg/mL of Nal-P-113; and f, control without P. gingivalis W83 or Nal-P-113. Morphometric analysis was used to evaluate alveolar bone loss. Microbiological assessment of the presence of Porphyromonas gingivalis and total bacteria was performed using absolute quantitative real-time PCR and scanning electron microscopy. Gingival tissue was collected for western blot and immunohistochemical assays of IL-1ß and TNF-α levels. RESULTS: Alveolar bone loss was inhibited by 100 µg/mL or 400 µg/mL of Nal-P-113 compared to the control group (P < 0.05). Lower amounts of P. gingivalis and total bacteria were found in groups d and e compared with group a (P < 0.05). A decrease in the levels of IL-1ß and TNF-α was detected in group d and group e compared to the control group (P < 0.05). The amount of P. gingivalis was positively correlated with IL-1ß and TNF-α expression in periodontal tissue (P < 0.05). CONCLUSIONS: Nal-P-113 exhibited protective effects on Porphyromonas gingivalis-induced periodontitis in rats by limiting the amount of bacteria and modulating IL-1ß and TNF-α production. The use of Nal-P-113 in vivo might serve as a beneficial preventive or therapeutic approach for periodontitis.

Chemical Constituents from Campylotropis hirtella.

A phytochemical investigation on the roots of Campylotropis hirtella afforded nine new isoflavones (3-9, 12, 15), two new isoflavans (10 and 11), one new coumestan (1), and three new prenylated benzoic acid derivatives (2, 13, 14), together with twenty-four known compounds. Their structures were established by spectroscopic analysis and circular dichroism data. The isolated compounds were also evaluated for their antibacterial activities against Enterococcus faecalis, Salmonella gallinarum, Streptococcus suis, Streptococcus agalactiae, Aeromonas hydrophila, Pseudomonas aeruginosa, Bacillus subtilis, Riemerella anatipestifer, and Vibrio alginolyticus.

A new phenyldilactone from Lespedeza cuneata.

A new phenyldilactone, maysedilactone B (1), together with twenty known compounds, were isolated from the aerial parts of Lespedeza cuneata. The structural elucidation of the isolated compounds was primarily based on HR-ESI-MS, IR and 1D and 2D NMR analyses. Compounds 1-8 and 15-21 were tested for cytotoxicity against four human tumor cell lines (A549, HCT116, SKOV3, and HepG2) using MTT method in vitro, while no significant activities were observed for the evaluated compounds.

[Advances in studies on modification technology of traditional Chinese medicine powders].

Most of the traditional Chinese medicine (TCM) powders showed bad physical properties, such as poor flowability, high hygroscopicity, agglomeration and poor wettability, which will affect the production process and even the efficacy of Chinese materia medica preparations. The exact characterization of the physical properties of TCM powders and the reshaping technology become the key to improve the quality and efficacy of Chinese materia medica preparations and to promote the modernization process of TCM. This article summarizes the evaluation methods of the physical properties and the modification technology of TCM powders, in order to solve the problems existing in the research and production of Chinese materia medica preparations, and to achieve the quality control of drugs and modernization of dosage forms.

[Advance in studies on biotransformation of flavonoids by intestinal bacteria].

Flavonoids are widely distributed in the nature, and have various biological activities. Flavonoids can be degraded by intestinal bacteria, so as to impact their bioavailability in vivo. Studies on metabolism of flavonoids by intestinal bacteria could provide basis for screening out biotransformation of flavonoids and interpreting their in vivo metabolic process. Being taken as the lead compounds, flavonoids can be modified by intestinal bacteria to achieve new compounds with high efficiency, bioavailability and solubility, which lays a foundation for the research and development of new drugs, selection of drug dosage forms and drug production. This article summarizes the main reaction types and impacting factors of intestinal bacteria on biotransformation of flavonoids, for reference of studies on biotransformation.