Search

Isoquercitrin (quercetin-3-O-β- d -glucopyranoside) possess various pharmacological effect as a biologically active compound. The aim of the present study was to investigate its potential effects on the proliferation and osteoblastic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) in vitro and bone formation in the mid-palatal suture during rapid maxillary expansion (RME) in vivo. Cell proliferation of rat BMSCs was detected by cell-counting kit- 8 (CCK-8) assay. Alkaline phosphatase (ALP) activity assay and alizarin red staining were used to evaluate osteogenic differentiation of BMSCs. Furthermore, the expression levels of osteogenesis-related genes including runt-related transcription factor 2 (Runx2), bone sialoprotein (BSP) and activating transcription factor 6 (ATF6) were measured by real-time RT-PCR. In vivo, thirty-six male 6-week-old Wistar rats with or without suture expansion receive systemic administration of isoquercitrin or saline solution. Micro-CT, HE and Masson staining were used to compare the morphological changes between the groups. Bone morphogenetic protein 2 (BMP2) expression in the suture was detected using immunohistochemical staining. Our results showed that isoquercitrin significantly promoted cell proliferation, ALP activity and mineral deposition in the range from 0.01 to 1 μM. Moreover, the expression levels of Runx2, BSP and ATF6 were also upregulated. The measurement of micro-CT imaging and histological examinations demonstrated that daily oral administration of isoquercitrin (10 mg/kg) increased bone formation compared to the other groups. Furthermore, the expression level of BMP2 was also augmented in the presence of isoquercitrin. Consequently, those findings showed that isoquercitrin exerts stimulatory effects on osteogenesis in vitro and in vivo, suggesting that isoquercitrin could be a potential candidate for preventing relapse following RME within palatal sutures.

To study the pharmacokinetics of Erhuang decoction extracts, a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was established for the determination of effective substances in rat plasma. The extracts prepared by water extraction (WE) method were given to rats by oral administration. After collected from the orbital venous plexus, plasma was treated by protein precipitation method. Then, the concentration of index components, including baicalin, liquiritin, berberine, palmatine and glycyrrhetinic acid, were determined by HPLC-MS/MS. Gradient elution mode was used to the chromatographic separation with an Inertsil ODS-SP column (100 mm×2.1mm, 5μm), with acetonitrile and 0.1% formic acid containing 10mmolL-1 ammonium acetate as the mobile phase. MS analysis was conducted by multiple reactions monitoring (MRM) with Electrospray Ionization (ESI). The extraction recoveries of the five active ingredients from plasma were greater than 86.04%, and the intra- and inter-day precisions were less than 16.57%. Results indicated that active ingredients in plasma of rats with oral administration of extracts showed certain difference in the pharmacokinetic parameters, which proved that the active ingredients were effectively absorbed. The established HPLC-MS/MS analytical method was sensitive and accurate, suitable for the pharmacokinetic study of active ingredients in Erhuang decoction.

The aim of the present study is to investigate the effects of hypertension on the gap junctions between vascular smooth muscle cells (VSMCs) in the cerebral arteries (CAs) of spontaneously hypertensive rats (SHRs). The functions of gap junctions in the CAs of VSMCs in SHRs and control normotensive Wistar-Kyoto (WKY) rats were studied using whole-cell patch clamp recordings and pressure myography, and the expression levels of connexins were analyzed using reverse transcription-quantitative polymerase chain reaction and Western blot analyses. Whole-cell patch clamp measurements revealed that the membrane capacitance and conductance of in situ VSMCs in the CAs were significantly greater in SHRs than in WKY rats, suggesting that gap junction coupling is enhanced between VSMCs in the CAs of SHRs. Application of the endothelium-independent vasoconstrictors KCl or phenylephrine (PE) stimulated a greater vasoconstriction in the CAs of SHRs than in those of WKY rats. The EC50 value of KCl was 24.9 mM (n = 14) and 36.9 mM (n=12) for SHRs and WKY rats, respectively. The EC50 value of PE was 0.9 µM (n = 7) and 2.2 µM (n = 7) for SHRs and WKY rats, respectively. Gap junction inhibitors 18β-glycyrrhetinic acid (18β-GA), niflumic acid (NFA), and 2-aminoethoxydiphenyl borate (2-APB) attenuated KCl-induced vasoconstriction in SHRs and WKY rats. The mRNA and protein expression levels of the gap junction protein connexin 45 (Cx45) were significantly higher in the CAs of SHRs than in those of WKY rats. Phosphorylated Cx43 protein expression was significantly higher in the CAs of SHRs than in those of WKY rats, despite the total Cx43 mRNA and protein expression levels in the cerebral artery (CA) exhibiting no significant difference between SHRs and WKY rats. Increases in the expression of Cx45 and phosphorylation of Cx43 may promote gap junction communication among VSMCs in the CAs of SHRs, which may enhance the contractile response of the CA to vasoconstrictors.

Niflumic acid (NFA) is a novel gap junction (GJ) inhibitor. The aim of the present study was to investigate the effect of NFA on GJ communication and the expression of connexin (Cx) in vascular smooth muscle cells (VSMCs) of mesenteric arterioles of spontaneously hypertensive rats (SHR). Whole-cell patch clamp recording demonstrated that NFA at 1×10–4 M significantly inhibited the inward current and its effect was reversible. The time for charging and discharging of cell membrane capacitance (Cinput) reduced from 9.73 to 0.48 ms (P

To observe the effect of icariin on turnover of paradentium as well as the mechanism of effects on osteoclast during orthodontic tooth movement in rats.Forty-right SD rats were used to establish animal models of OTM and divided into two groups randomly: the control group and the experimental group. Rats in the experimental group were given 20 mg/（kg.d） icariin by intragastric administration, while rats in the control group received solvent with the same volume. The rats were sacrificed in batch on the 7th, 14th, 21st and 28th day after orthodontic treatment. The amount of tooth movement was measured, and histomorphometric analysis based on slices from periodontium adjacent to the maxillary first molars was used to observe new bone formation, bone resorption and quantify osteoclasts. Statistical analysis was performed by using SPSS 16.0 software package.The movement distance of the first molar was significantly larger in the icariin group than that in the control group (P0.05). In the icariin group, the number of osteoclasts was significantly higher than the control group at the 7th day and then demonstrated a steady decrease.Icariin could accelerate OTM in rats through promoting bone turnover of alveolar bone.

To investigate the effects of strontium ranelate on the expression of BMP-2 during rapid maxillary expansion.Thirty-six male 6-week- old male Wistar rats were selected. They were randomly divided into 3 groups. Group A was designed as a control group. An expanded application producing 100 g force was fixed between the first and the second molar on both sides of the rats in group B and group C. 600 mg/kg strontium ranelate was given to the rats in group C daily via an orogastric route, while the equal normal saline was given to the rats in group B. Then the rats were sacrificed on day 4, 7 and 10. The expression of BMP-2 which is a sign of bone formation was detected with immunohistochemical staining and analyzed with Image-pro plus 5.0. SPSS19.0 software package was used for statistical analysis.The expression of BMP-2 in the midpalatal suture was significantly greater in group B than that in group A on day 4 (P0.05); however, there was no significant difference between group A and group B on day 7 and 10 (P0.05). The expression of BMP-2 in the midpalatal suture in group C was significantly greater than that in the other two groups at each time point (P0.05).Strontium ranelate promotes the expression time and quantity of BMP-2 in the mid-palatal suture of rats during rapid maxillary expansion and may accelerate bone formation during rapid maxillary expansion.

Flavonoid glycosides are metabolized by intestinal bacteria, giving rise to a wide range of phenolic acids that may exert systemic effects in the body. The microbial metabolism of flavonoids extracted from the leaves of Diospyros kaki (FLDK) by intestinal bacteria was investigated in vitro. High-performance liquid chromatography/linear trap quadrupole orbitrap mass spectrometry was performed to analyze the metabolites of flavonoids in vivo using Xcalibur2.1 software. The results showed that the levels of flavonoid glycosides and flavonoid aglycones decreased rapidly in the process of microbial metabolism by intestinal bacteria in vitro, and the metabolic rate may be related to the concentration of intestinal bacteria in the culture solution. In vivo metabolites of FLDK were detected in rat plasma and urine after oral administration of FLDK. Eight flavonoids were identified in the urine, and three were identified in the plasma; however, flavonoid aglycones were not found in the plasma.

Objective: To explore the analgesic and anti-inflammatory effects of lappaconitine gelata (LA). Methods: The writhing response induced by acetic acid, the pain response induced by formaldehyde and hot plate method in the mouse, and the paw edema induced by egg albumen in the rat and the ear edema induced by xylene in the mouse were used for investigation on the analgesic and anti-inflammatory effects of LA. Results: The writhing response induced by acetic acid, the pain response induced by formaldehyde and hot plate methods was significantly inhibited by LA. In addition, the paw edema induced by egg albumen in the rat and the ear edema induced by xylene in the mouse were all significantly suppressed by LA. Conclusion: LA has the analgesic and anti-inflammatory effects.

The mechanism underlying the modulatory effect of substance P (SP) on GABA-activated response in rat dorsal root ganglion (DRG) neurons was investigated. In freshly dissociated rat DRG neurons, whole-cell patch-clamp technique was used to record GABA-activated current and sharp electrode intracellular recording technique was used to record GABA-induced membrane depolarization. Application of GABA (1–1000 μmol/L) induced an inward current in a concentration-dependent manner in 114 out of 127 DRG neurons (89.8 %) examined with whole-cell patch-clamp recordings. Bath application of GABA (1–1000 μmol/L) evoked a depolarizing response in 236 out of 257 (91.8%) DRG neurons examined with intracellular recordings. Application of SP (0.001–1 μmol/L) suppressed the GABA-activated inward current and membrane depolarization. The inhibitory effects were concentration-dependent and could be blocked by the selective neurokinin 1 (NK1) receptors antagonist spantide but not by L659187 and SR142801 (1 μmol/L, n=7), selective antagonists of NK2 and NK3. The inhibitory effect of SP was significantly reduced by the calcium chelator BAPTA-AM, phospholipase C (PLC) inhibitor U73122, and PKC inhibitor chelerythrine, respectively. The PKA inhibitor H-89 did not affect the SP effect. Remarkably, the inhibitory effect of SP on GABA-activated current was nearly completely removed by a selective PKCe inhibitor epilon-V1-2 but not by safingol and LY333531, selective inhibitors of PKCα and PKCβ. Our results suggest that NK1 receptor mediates SP-induced inhibition of GABA-activated current and membrane depolarization by activating intracellular PLC-Ca2+-PKCe cascade. SP might regulate the excitability of peripheral nociceptors through inhibition of the “pre-synaptic inhibition” evoked by GABA, which may explain its role in pain and neurogenic inflammation.

To prepare Kushen-Dilong nanoemulsion and nanoemuls-ion gel, and investigate its content, physical and chemical properties. Their transdermal properties in vitro were studied as well.IPM acted as oil phase, EL35 as surfactant, EtOH as cosurfactant, Pheretima aqueous solution was added dropwise to the oil phase to prepare Kushen-Dilong nanoemulsion at room temperature using magnetic stirring. HPLC was used to determine the content of matrine and oxymatrine in the nanoemulsion. Transmission electron microscopy and laser particle size analyzer was used to determine the shape and size of the nanoemulsion. NP700 was used as substrate to prepare Kushen-Dilong nanoemulsion gel. Franz diffusion cell was used for the nanoemulsion and gel transdermal characteristics in vitro.The Kushen-Dilong nanoemulsion was O/W nanoemulsion, its uniform particle size was 20.6 nm with roundness appearance and stable content. The steady-state permeation rate of Kushen-Dilong nanoemulsion, nanoemulsion gel, saturated aqueous solution, hydro gel were 0.1484, 0.1183, 0.0306, 0.0321 mg x cm(-2) x h(-1), respectively.The 24 h cumulative infiltration and infiltration rate of Kushen-Dilong nanoemulsion and nanoemulsion gel were better than the saturated aqueous solution and hydro gel, which could provide a new dosage form for Kushen-Dilong transdermal drug delivery.

The research aimed at investigating the physicochemical properties, stability and skin penetration in vitro of total alkaloids of Sophora flavescens nanoemulsion. Prepare total alkaloids of S. flavescens nanoemulsion and detect the determination of matrine and oxymatrine in the nanoemulsion using HPLC method. Transmission electron microscopy and laser particle size analyzer were utilized to detect the shape and size of the nanoemulsion respectively. And also the stability of nanoemulsion was studied under the conditions of low temperature (4 degrees C), normal temperature (25 degrees C) and high temperature (60 degrees C). Franz diffusion cell was used to research the transdermal absorption of nanoemulsion in vitro. The results found that the nanoemulsion we prepared presented appearance of rounded, uniform; its average diameter was (15.55 +/- 2.24) nm, and particle size distribution value was 0. 161; the appearance, diameter and percentage determination of total alkaloids of S. flavescens had no variations after 15 d under 4, 25, 60 degrees C respectively. The steady-state permeation rate was 4.564 1 microg x cm(-2) x h(-1), 24 h cumulative amount of penetration was 110.7 microg x cm(-2), which was 1.86 fold of 24 h cumulative amount of aqueous solution (59.41 microg x cm(-2)). All the results demonstrated total alkaloids of S. flavescens nanoemulsion had good permeability, and could provide a new preparation for its clinical application.

To study the effects of different penetration enhancers on the transcutaneous permeability of lappaconitine gel in vitro and therefore to screen out the effective accelerator to enhance the permeation rate of lappaconitine.Using improved Franz-type diffusion cell and excised big mouse skin in vitro as transdermal barrier, the kinetics parameters such as cumulative permeation quantity, permeation rate and permeation lagged time were determined by HPLC. The enhancement ability of four different enhancers such as azone (Azone), propylene glycol (PG), oleic acid (OA) and lauryl alcohol (LA), was investigated when used either uniquely or combinatively each other at random.When used combinatively, Azone + PG, LA + PG, OA + PG can enhance the cumulative permeation quantity, OA + PG was the best one among them.The selection of the best penetration enhancers provided reference for lappaconitine transdermal delivery.