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Background and objective Oxidative stress has been suggested as an important pathogenic factor contributing to chronic periodontitis with diabetes mellitus (CPDM). Previous studies have revealed the potential therapeutic properties of baicalein (BCI) in oxidative stress-related diseases; however, the antioxidant effects of BCI on therapy for individual with CPDM remain largely unexplored. Nuclear factor erythroid 2-related factor 2 (Nrf2) plays a critical role in cellular defence against oxidative stress. In this study, we aim to determine whether BCI prevents diabetes-related periodontal tissue destruction by regulating Nrf2 signaling pathway. Material and methods Human gingival epithelial cells (hGECs) were challenged with high glucose (HG, 25 mmol/L) and/or lipopolysaccharide (LPS, 20 µg/mL). Reactive oxygen species (ROS) were detected by fluorescence-activated cell sorting. The changes of antioxidant-related genes, including Nrf2, catalase (Cat), glutamate-cysteine ligase catalytic subunit (Gclc), superoxide dismutase 1 (Sod1), and superoxide dismutase 2 (Sod2), were quantified by real-time PCR. The localization of phospho-Nrf2 (pNrf2, S40) in the nucleus was detected by immunofluorescence staining and laser scanning confocal microscope (LSCM). PNrf2 and total form of Nrf2 were determined using western blot. The above indicators together with mitochondrial membrane potential (MMP) were further investigated in hGECs pre-treated with different concentrations of BCI (0.01, 0.1, or 0.5 µg/mL) before stimulated with HG plus LPS (GP). Finally, the role of BCI in activating Nrf2 signaling pathway and relieving the alveolar bone absorption was examined in the CPDM model of Sprague Dawley rats. CPDM rats were oral gavaged with BCI (50, 100, or 200 mg/kg daily). The pNrf2 was detected by immunohistochemistry, and the alveolar bone absorption was examined by microcomputed tomography. Results Our results showed that ROS were significantly increased in both groups of HG and LPS, with the strongest generation in the GP group. In terms of ROS-related gene expression, we found that the mRNA levels of Nrf2, Cat, Gclc, Sod1, and Sod2 were significantly decreased in HG and LPS groups. In consistent with the strongest induction of ROS in GP group, the gene expression in GP group was further decreased as compared to those of HG and LPS groups. Also, the expression of pNrf2 exhibited the same trend with the expression of those antioxidant genes. However, the generation of ROS and the loss of mitochondrial membrane potential induced by GP were abolished by pre-treatment with different concentrations of BCI (0.01, 0.1, or 0.5 µg/mL). Interestingly, we observed that BCI promoted the nucleus translocation of pNrf2, as well as the gene expression levels of pNrf2 and its target genes (Cat, Gclc, Sod1, and Sod2). Finally, in the CPDM animal model, we found that BCI (at concentrations: 50, 100, and 200 mg/kg) markedly increased the number of pNrf2-positive cells in periodontal tissue and mitigated the alveolar bone loss. Conclusions Our data revealed a potential role for clinic application of BCI under CPDM conditions, suggesting a new therapeutic drug for CPDM patients.

Coptidis Rhizoma binds to the membrane receptors on hPDLSC/CMC, and the active ingredient Berberine (BER) that can be extracted from it may promote the proliferation and osteogenesis of periodontal ligament stem cells (hPDLSC). The membrane receptor that binds with BER on the cell surface of hPDLSC, the mechanism of direct interaction between BER and hPDLSC, and the related signal pathway are not yet clear. In this research, EGFR was screened as the affinity membrane receptor between BER and hPDLSC, through retention on CMC, competition with BER and by using a molecular docking simulation score. At the same time, the MAPK PCR Array was selected to screen the target genes that changed when hPDLSC was simulated by BER. In conclusion, BER may bind to EGFR on the cell membrane of hPDLSC so the intracellular ERK signalling pathways activate, and nuclear-related genes of FOS change, resulting in the effect of osteogenesis on PDLSC.

We have developed an online analytical method that combines human periodontal ligament cell membrane chromatography (hPDLC/CMC) with high-performance liquid chromatography and mass spectrometry (LC/MS) for recognizing and identifying osteoplastic active components from Coptidis Rhizoma. Retention fractions on hPDLC/CMC were enriched onto an enrichment column and the components were directly analyzed by combining a 10-port column switcher with an LC/MS system for separation and preliminary identification. Using simvastatin (SIM) as a positive control, berberine from Coptidis Rhizoma was identified as the active component which could act on the hPDLC. The MTT colorimetric assay, alkaline phosphatase (ALP) activity, and staining tests revealed that berberine could promote hPDLC growth, increase the secretion of ALP in the culture medium, and enhance the formation of mineralized nodule, thus it is a potential osteoplastic ingredient. This hPDLC/CMC-online-LC/MS method can be applied for screening active components acting on hPDLC from traditional Chinese medicines exemplified by Coptidis Rhizoma and will be of great utility in drug discovery using natural medicinal herbs as a source of leading compounds.

Diameter of nanoparticles plays a vital role in tribological properties of lubricanting oil. Three kinds of nano-copper with different diameters (50nm, 65nm, 80nm) were produced using the electric explosion of metallic wire (EEW), and their diameters were characterized by Scanning Electron Microscope (SEM). The tribological properties of the lubricating oils containing nano-copper additives were investigated using friction wear testing machine, and the wear scar morphology photographs were observed by means of continuously multiple microscope. The results show that lubricanting oil with the large diameter of 80nm copper particles and the weight percentage of 1.0% ~ 1.2% has good characteristic of extreme pressure ; while the lubricanting oil with the small diameter of 50nm copper particles and the weight percentage of 1.2% provides good properties of anti-wear and friction reducing. This has a guiding role in selecting nanooil additives.

An eficent, one-pot procedure is reported for the synthesis of N-trifluoroacetyl adriamycin-14-valerate (AD-32, 3) from daunorubicin (1) in 35% overall yield.

In present study, an online analytical method using human periodontal ligament cell/cell membrane chromatography (hPDLC/CMC) combined with high-performance liquid chromatography/mass spectrometry (HPLC/MS) was used for direct recognition, separation, and identification of compounds for the first time from Scutellaria baicalensis Georgi (SBG) that are active on hPDLCs. Baicalein (BAI) and wogonin (WOG), which were identified as the active compounds of the ethyl ether extract of S. baicalensis Georgi (SBGEE), could bind to the same membrane receptor of hPDLC for simvastatin (SIM). Moreover, BAI (0.15-0.6 mg/L) and WOG (0.015-0.6 mg/L) had the capability to enhance cell proliferation, matrix calcification, and formation of calcified nodules, which are comparable to the activities of SIM (0.1 mg/L) in vitro. These observations are consistent with the K(A) of the various drugs. It is very important for the development of SBG used to treat periodontitis.

The title compound, C22H20O8, a product of oxidation of podophyl­lotoxin, a lignan of the phenyl­tetralin type, represents a synthon for potential antitumour agents. It has the same configuration of three chiral centres as the starting material, podophyl­lotoxin, and, as well as the latter, contains a γ-lactone ring trans-fused to the tricylic system. Non-classical C—H⋯O hydrogen bonds link the mol­ecules in the crystal structure into infinite chains along the a axis.