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Efficient transcytosis across the blood-brain-barrier is an important strategy for accessing drug targets within the central nervous system. Ligusticum chuanxiong Hort. was used as a messenger drug to increase the distribution of drugs in brain tissue in Traditional Chinese Medicine. The present study investigates the transport of echinacoside (ECH) through MDCK-MDR1 cell and the effects of ligustilide (LIG), senkyunolide A (SENA) and senkyunolide I (SENI) in chuanxiong on its transport. The results indicated that the absorption of ECH was relatively poor in MDCK-MDR1cells, and was concentration dependent and not saturable. The P-glycoprotein inhibitor verapamil could significantly increase the transport of ECH. It indicated that the transport mechanism might be passive diffusion as the dominating process with the active transportation mediated mechanism involved. The increased apparent permeability of ECH in A → B direction by ethylenediaminetetraacetic acid-Na2 suggested that ECH was absorbed via the paracellular route. The transport of ECH in A → B direction significantly increased when co-administrated with increasing concentrations of LIG, SENI and SENA. Western blot analysis and a decrease in transepithelial electrical resistance during the permeation experiment indicated that LIG, SENI and SENA had enhanced the transport of ECH in the BBB models attribute to down-regulate the expressions of claudin-5 and zonula occludens-1 expression. [ABSTRACT FROM AUTHOR]

To overcome the limitations of the conventional particle size reduction technologies, a novel combinative particle size reduction method for the effective production of homogeneous nanosuspensions was investigated. Ursodeoxycholic acid, a poorly soluble drug representative, was tried to prepare nanosuspension by homogenization technology and high-pressure precipitation tandem homogenization technology. It was shown that the combinative approach could significantly improve the particle size reduction effectiveness over conventional homogenization approach. The Box-Behnken design analysis for process optimization revealed that the acceptable UDCA-NS was obtained wherein the optimal values of A, B, C and D were 10%, 500 bar, 0.125 and 600 bar, respectively. SEM results demonstrated that no significant aggregation or crystals growth could be observed in the freeze-dried UDCA nanocrystals. The DSC and XRD results showed that UDCA remained in a crystalline state. Dissolution velocities of the freeze-dried UDCA-NS powder were distinctly superior compared to those of the crude powder and physical mixture. The high-pressure precipitation tandem homogenization technology can be a good choice for nanosuspension preparation of poorly soluble UDCA, due to high efficiency of particle size reduction. [ABSTRACT FROM AUTHOR]

The objective of this study was to prepare and characterize geniposide-pharmcosomes (GP-PMS) and optimize the process and formulation variables using response surface methodology. Tetrahydrofuran was used as a reaction medium, GP and phospholipids were resolved into the medium, and GP-PMS was formed after the organic solvent was evaporated off under vacuum condition. The process and formulation variables were optimized by central composite design (CCD) of response surface methodology (RSM). The phospholipid-to-drug ratio (X1), reaction temperature (X2) and the drug concentration (X3) were selected as independent variables and the yield (%) of GP 'present as a complex' in the PMS was used as the dependent variable. The physico-chemical properties of the complex obtained by optimal parameters were investigated by means of Fourier transform infrared spectrophotometry (FT-IR), differential scanning calorimetry, n-octanol/water partition coefficient (P) and particle size analysis. Multiple linear regression analysis for optimization by CCD revealed that the higher the yield of GP 'present as a complex' in the GP-PMS was obtained wherein the optimal settings of X1, X2 and X3 are 3, 50°C and 5.5 mg/mL, respectively. The DSC and IR studies of GP-PMS by the optimal settings demonstrated that GP and phospholipids in the GP-PMS were combined by non-covalent bond, not forming a new compound. GP-PMS could significantly increased the lipophilicify of GP, and P of GP-PMS in n-octanol and water was about 20 multiples more than that of GP material. Pharmacosomes could be an alternative approach to improve the absorption and permeation of biologically active constituents. [ABSTRACT FROM AUTHOR]

Aromatic traditional Chinese medicines have a long history in China, with wide varieties. Volatile oils are active ingredients extracted from aromatic herbal medicines, which usually contain tens or hundreds of ingredients, with many biological activities. Therefore, volatile oils are often used in combined prescriptions and made into various efficient preparations for oral administration or external use. Based on the sources from the database of Newly Edited National Chinese Traditional Patent Medicines (the second edition), the author selected 266 Chinese patent medicines containing volatile oils in this paper, and then established an information sheet covering such items as name, dosage, dosage form, specification and usage, and main functions. Subsequently, on the basis of the multidisciplinary knowledge of pharmaceutics, traditional Chinese pharmacology and basic theory of traditional Chinese medicine, efforts were also made in the statistics of the dosage form and usage, variety of volatile oils and main functions, as well as the status analysis on volatile oils in terms of the dosage form development, prescription development, drug instruction and quality control, in order to lay a foundation for the further exploration of the market development situations of volatile oils and the future development orientation.

Responsive drug delivery system can release drug at specific time and sites, and effectively overcome the drug resistance of organisms. With such advantages as drug protection, local targeting, inhibition of enzymatic activity, memory and expression, it has good prospect of application. So far, many chemical preparations have been launched in the market. This article mainly summarizes the advance in studies on establishment methods of responsive drug delivery system, while proposing research ideas for the traditional Chinese medicine component-based responsive drug delivery system according to the multi-component, multi-link and multi-target characteristics, in the expectation of providing reference and thought for the development of the drug delivery system.

To determine the concentration of gastrodigenin in tissue homogenates with high performance liquid chromatography (HPLC) , in order to study the changes of the distribution of gastrodigenin before and after combined application in rat tissues, including heart, liver, spleen, lung, kidney and brain tissues. The study showed that gastrodigenin could be found in kidney, liver, heart, lungs, spleen and brain tissues. After the combined application of Gastrodiae Rhizoma and Ligustici Wallichii Rhizoma, the content of gastrodigenin decreased in kidney and liver to varying degrees, while increasing in lung and brain. This indicated that Ligustici Wallichii Rhizoma had certain impact on the in vivo distribution of gastrodigenin, an active ingredient in Gastrodiae Rhizoma, because it could improve gastrodigenin's distribution in lung and brain tissues. The study provides scientific basis for the combined application of Gastrodiae Rhizoma and Ligustici Wallichii Rhizoma in treating brain diseases.

Nanocrystal suspensions drug delivery system is used to solve the delivery difficulty of poorly soluble drug. However, the physical stability of liquid nanocrystal suspensions is very bad. Solid nanocrystal delivery system as a novel technology, can improve the thermokinetics stability of nanocrystal suspensions and have good clinical compliance, which can achieve stabilization of nanocrystal suspension systems as an ideal delivery system. In this paper, we reviewed the research progress of nanotechnology and solidification technology of solid nanocrystal suspension delivery system, which will give the new mirrors and thoughts on the development of solid nanocrystal delivery system.

The free membrane of Eudragit L100/S100 which is pH-sensitive, colon-specific was prepared by plane casting films. The film humidity, species and amount of plasticizers, the ratio of membrane material was investigated. The rate of membrane permeability and mechanical properties were used as indicators of orthogonal experiment, and its related properties were studied. The results show that the mechanical properties of the membrane and phragmoid capacity are the best when 30% TEC was used as plasticizer; the ratio of membrane material have little effect on the rate of membrane permeability and mechanical properties. By adjusting the species and amount of plasticizers, the ratio of Eudragit L100/S100, the free membrane which is colon-specific can be obtained.

The release kinetics research of sustained-release formulations of traditional Chinese medicines (TCM) is an inalienable part of the chain of TCM modernization, which plays an important role in the development of modern compound TCM preparation. However, the research method or pattern in line with the specific characteristics of TCM, i.e., multi-component and multi-target, is still lacking. On the basis of material rough set theory, this paper reviewed the advantages and disadvantages of the existing evaluation patterns and methods, a tentative idea about the "total amount" release characteristics evaluation on TCM compound sustained-release preparation has suggested so as to evaluate the release kinetics and to promote the development of evaluation methodology on TCM sustained-release preparations.