Résumé
The present study explored the effect of co-amorphous technology in improving the dissolution rate and stability of silybin based on the puerarin-silybin co-amorphous system prepared by the spray-drying method. Solid-state characterization was carried out by powder X-ray diffraction(PXRD), polarizing microscopy(PLM), Fourier transform infrared spectroscopy(FT-IR), differential scanning calorimetry(DSC), etc. Saturated powder dissolution, intrinsic dissolution rate, moisture absorption, and stability were further investigated. The results showed that puerarin and silybin formed a co-amorphous system at a single glass transition temperature which was higher than that of any crude drug. The intrinsic dissolution rate and supersaturated powder dissolution of silybin in the co-amorphous system were higher than those of the crude drug and amorphous system. The co-amorphous system kept stable for as long as three months under the condition of 40 ℃, 75% relative humidity, which was longer than that of the single amorphous silybin. Therefore, the co-amorphous technology could significantly improve the dissolution and stability of silybin.
Sujets)
Calorimétrie différentielle à balayage , Dessiccation , Préparation de médicament/méthodes , Stabilité de médicament , Silymarine , Solubilité , Spectroscopie infrarouge à transformée de Fourier , Technologie , Diffraction des rayons XRésumé
Objective:To investigate the relationship between phase behavior of curcumin (CUR) from self-nanoemulsion drug delivery system (SNEDDS) and stability of the formed nanoemulsion in artificial gastrointestinal fluid. Method:The growth rate of precipitation after dispersion of CUR-SNEDDS was expressed by the change tendency of CUR supersaturation-time curve. The effect of drug loading on crystal nucleation and growth was investigated by ultraviolet-visible spectrometry and polarized light microscope, respectively. X-ray powder diffraction (XRD) and differential scanning calorimetry (DSC) were used to analyze the precipitation forms of CUR-SNEDDS with different drug loading in artificial gastrointestinal fluid. At the same time, the effect of drug loading on the quality stability of nanoemulsion formed by CUR-SNEDDS in artificial gastrointestinal fluid was investigated. Result:In the artificial gastrointestinal fluid, with the increase of drug loading, the area under the supersaturation-time curve of CUR was increased (100% drug loading≈90% drug loading>75% drug loading), the crystallization nucleation and growth rate were accelerated (100% drug loading>90% drug loading>75% drug loading), the amorphous proportion in the precipitation composition decreased, the nanoemulsion droplets adhered and distributed unevenly, the particle size and dispersivity were increased. Conclusion:High drug loading promotes the nucleation and growth of crystals, and increases the proportion of crystal forms in the precipitation composition, which leads to the decrease in the stability of the formed nanoemulsion. Therefore, it is suggested that the drug loading of CUR-SNEDDS needs to be controlled below 90%.
Résumé
Objective: To study the relationship between the drug form of curcumin self-nano-emulsion (Cur-SNEDDS) after being dispersed in artificial gastrointestinal fluid and intestinal absorption in rats. Methods: The change trend of curcumin concentration-time curve was used to express the change of precipitation growth. The content and existing form of precipitation were studied by polarized light microscope (PLMC), HPLC, UV full-wavelength (UV) scanning, X-ray powder diffraction (XRD), differential scanning calorimeter (DSC), infrared spectrum (FT-IR), Raman spectrum and nuclear magnetic resonance hydrogen spectrum (1H-NMR). At the same time, the rat valgus intestinal sac model was used to investigate the effect of SNEDDS on the apparent permeability coefficient (Papp) of curcumin. Results: The content of curcumin in the precipitation produced by Cur-SNEDDS dispersion was about 95% of that of curcumin API, and the chemical structure did not change, but the crystal form changed, resulting in amorphous precipitation. Curcumin intermolecular interaction occurred in the dispersion system, and hydrogen bonds were formed. Compared with curcumin, Cur-SNEDDS significantly increased the release rate and degree of curcumin in vitro, and enhanced the absorption of curcumin in duodenum, jejunum, ileum and colon, and the Papp value increased by 6.22, 12.97, 25.71 and 36.75 times, respectively. Conclusion: After Cur-SNEDDS dispersion, the crystal structure of curcumin is changed, which exists in free, amorphous and crystal form, so as to significantly improve the in vitro release and intestinal absorption of curcumin.
Résumé
In order to improve the supersaturation and maintenance time of drug dispersion in curcumin self-nanoemulsion(CUR-SNEDDS), precipitation inhibitors(PPIs) were introduced to prepare curcumin supersaturated self-emulsion(CUR-SSNEDDS). The composition of CUR-SNEDDS prescriptions was selected through the solubility test, the compatibility of oil phase and surfactant, the investigation of the emulsifying ability of the surfactant and the drawing of the pseudo-ternary phase diagram. Analytic hierarchy process was used in combination with central composite design-response surface method to optimize the prescription. The type and dosage of precipitation inhibitors(PPIs) were selected to maintain the supersaturated concentration and duration of CUR in artificial gastrointestinal fluids. At the same time, polarizing microscope was used to evaluate the crystallization inhibition effect and the quality and in vitro release behavior of CUR-SSNEDDS. The prepared CUR-SSNEDDS prescription was capryol 90-kolliphor RH40-transcutol HP-Soluplus(7.93∶66.71∶25.36∶5), with the drug loading of(65.12±1.25) mg·g~(-1). CUR-SSNEDDS was transparent yellow, and the nanoemulsion droplets were spherical with uniform distribution. The emulsification time was(21.02±0.13) s, the average particle size was(57.03±0.35) nm, the polydispersity index(PDI) was(0.23 ± 0.01), and the Zeta potential was(-18.10±1.30) mV. CUR-SSNEDDS significantly inhibited the generation and growth of crystals after in vitro dilution. The supersaturation could be maintained above 10 within 2 h, and the dissolution rate and degree of CUR in artificial gastrointestinal fluid were significantly increased. Soluplus could effectively maintain the supersaturated state of CUR and enhance CUR dissolution in vitro.
Sujets)
Biodisponibilité , Curcumine , Émulsions , Nanoparticules , Taille de particule , Solubilité , TensioactifsRésumé
This study aimed to investigate the influence of combinating Huangqi with Fuzi on the pharmacokinetics of six Aconitum alkaloids, i.e. aconitine (AC), hypaconitine (HA), mesaconitine (MA), benzoylaconine (BAC), benzoylhypaconine (BHA) and benzoylmesaconine (BMA). The plasma concentrations of the drugs were determined by LC-MS for dose response and time dependent curves. The pharmacokinetic parameters were calculated by DAS 3.3, and SPSS 12.0 was used to analyze the differences of main pharmacokinetic parameters between the two groups. Comparing with Fuzi group, the AUC0-t and AUC0-∞ of six alkaloids in Fuzi-Huangqi group was significantly decreased, the CLz/Fof six alkaloids except HA was significantly increased; the Cmax was decreased and the tmax was prolonged in 3 monoester alkaloids, and the apparent volume of distribution of BMA and MA (Vz/F) increases. These data indicated that Huangqi can inhibit the absorption of aconite alkaloids, induce the distribution of aconite alkaloids to the whole body, and accelerate the elimination of aconite alkaloids. The animal experiment scheme in this study has been approved by the Experimental Animal Ethics Committee of Jiangxi University of Traditional Chinese Medicine.
Résumé
Increasing evidence suggests that epigenetic dysfunction may influence the stability of normal pregnancy.The ten-eleven translocation (TET) family and 5-hydroxymethylcytosine (5-hmC) were found to be linked with epigenetic reprogramming.The present study aimed to examine the expression of the TET family and 5-hmC in the villi of human embryos and compared their expression between normal pregnancy and early pregnancy loss (EPL).Embryonic villi were collected from normal pregnant women (control) experiencing medical abortion and from EPL patients at gestation ages of 6,7 and 8 weeks.The mRNAs of TET family were analysed using quantitative polymerase chain reaction (qPCR),and TET proteins using Western blotting and immunohistochemical analysis.The MethylFlashTM Kit was used to quantify the absolute amount of 5-methylcytosine (5-mC) and 5-hmC.Our results showed that the expression of the TETs and 5-hmC in the normal villus decreased with increasing gestational age.Immunohistochemistry revealed that the TET proteins were expressed in the cytoplasm of trophoblasts and their expression was the highest in the 6-week tissue samples,which was consistent with the qPCR and Western blot results.The expression of TET1,TET2,and TET3 was lower in the villi in EPL group than in normal pregnancy group (P<0.05 for all).It was concluded that the TET family and 5-hmC are critical in epigenetic reprogramming of human embryo.The findings also suggest that a deficiency of TETs in the villus might be associated with human EPL.
Résumé
Increasing evidence suggests that epigenetic dysfunction may influence the stability of normal pregnancy.The ten-eleven translocation (TET) family and 5-hydroxymethylcytosine (5-hmC) were found to be linked with epigenetic reprogramming.The present study aimed to examine the expression of the TET family and 5-hmC in the villi of human embryos and compared their expression between normal pregnancy and early pregnancy loss (EPL).Embryonic villi were collected from normal pregnant women (control) experiencing medical abortion and from EPL patients at gestation ages of 6,7 and 8 weeks.The mRNAs of TET family were analysed using quantitative polymerase chain reaction (qPCR),and TET proteins using Western blotting and immunohistochemical analysis.The MethylFlashTM Kit was used to quantify the absolute amount of 5-methylcytosine (5-mC) and 5-hmC.Our results showed that the expression of the TETs and 5-hmC in the normal villus decreased with increasing gestational age.Immunohistochemistry revealed that the TET proteins were expressed in the cytoplasm of trophoblasts and their expression was the highest in the 6-week tissue samples,which was consistent with the qPCR and Western blot results.The expression of TET1,TET2,and TET3 was lower in the villi in EPL group than in normal pregnancy group (P<0.05 for all).It was concluded that the TET family and 5-hmC are critical in epigenetic reprogramming of human embryo.The findings also suggest that a deficiency of TETs in the villus might be associated with human EPL.
Résumé
To explore the mechanism of the absorption enhancement of Angelica dahurica extract (Ade), the absorption mechanism of baicalin in the Scutcllaria water extraction as well as the effect of Angelica dahurica extract on absorption of baicalin were investigated. In order to determine the main absorption site, everted intestinal sac model was used to study the effect of Angelica dahurica extract on the absorption of baicalin at duodenum, jejunum, ileum and colon. In situ single pass intestinal perfusion model was performed to study the absorption of various concentrations of baicalin and the effect of Angelica dahurica extract on the absorption of baicalin at the main absorption site. To authenticate the consequence of perfusion by getting the blood from the hepatic portal vein and determine the concentration of the baicalin in the blood. The result showed that baicalin could be absorbed at all of the four intestinal segments with increasing absorption amount per unit as follows: ileum > colon > jejunum > duodenum. The absorption ofbaicalin in the duodenum significantly increased with Angelica dahurica extract, thus, duodenum was chosen to be the studying site. Apparent permeability values (Papp) and absorption rate constant (Ka) of baicalin in the duodenum increased gradually with higher concentrations. When the concentration of baicalin rises to a certain degree, the absorption increase had a saturable process, the absorption of baicalin may be an active transportation. Baicalin may be not a substrate of P-gp as verapamil which had not significantly affected the Papp and Ka of baicalin. The absorption of baicalin in the duodenum significantly increased (P < 0.01) in the two models with Angelica dahurica extract and the concentration of baicalin in the blood from the hepatic portal vein showed that the Angelica dahurica extract can increase the absorption of baicalin.